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CROSS REFERENCES TO RELATED APPLICATIONS
The present application relates to and incorporates by reference Japanese Patent application No. 2004-015671 filed on Jan. 23, 2004.
BACKGROUND OF THE INVENTION
1. Technical Field of the Invention
The present invention relates to a method and apparatus for removably holding various medical devices such as endoscopes used, for example, during surgical operations in cranial nerve surgery.
2. Related Art
An apparatus for holding medical devices (medical-device holding apparatus) has been known, which has a polyarticular arm equipped with a holder that holds medical devices and joints equipped with brakes to selectively lock/unlock the turns of the arm. This medical-device supporting apparatus allows the holder to support, for example, an endoscope so that the endoscope is positioned to face a desired portion to be examined of a patient. In this attitude of the holder, the joints are locked to prevent a field of view of the endoscope from deviating outside the portion to be examined. Thus a surgeon is able to concentrate on the surgical operation, without being bothered by positional adjustment operations of the endoscope.
Meanwhile, as described in Japanese Patent Publication (unexamined) No. 2002-345831, the medical-device holding apparatus has a grasping member which is used to move the holder (i.e., the endoscope), wherein the grasping member is arranged close to the holder. That is, in order to lock and unlock the brakes in the joints, the grasping member is arranged to substantially be perpendicular to an insertion axis assigned to the endoscope and is equipped two operation switches secured thereon. Thus a surgeon grasps the grasping member and, at the same time, pushes those two operation switches by, usually, the first and middle fingers. This push operation allows the brakes to be activated, so that each joint is released from being locked. In other words, in the condition where both the two operation switches are not pressed at the same time (, or together), each joint will not be released from being fixed. It is therefore possible for a surgeon to worry about erroneous release operations of the brakes during a surgical operation, so that the surgeon can concentrate on the operation.
Further, in operating the medical-device holding apparatus, it is required that a surgeon's touch to the arm will not move the arm under the condition in which the brakes have been locked in the joints. To realize such a situation, a large amount of fixing force should be given to each brake. In contrast, with the arm made free (i.e., the locks are released), it should be constructed such that a medical device that has been held by the apparatus can be moved freely with a light amount of operator's force. In addition, with taking malfunctions and others of the joints, design is made such that the brakes sustain a certain specific level of braking force to prevent the arm from moving in such malfunction cases.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide a method and apparatus holding a medical device, which has the capability of selectively locking and unlocking the joints of an arm unit holding the medical device in a proper manner.
As one aspect, the present invention provides an apparatus for holding a medical device, comprising: an arm unit spatially movably holding a single medical device; an operation unit equipped with a plurality of operation members to be operated by an operator to enable the arm unit to move spatially; a determination unit determining whether or not an operator's operation at the plurality of operation members corresponds to an improper state deviating from a properly operated state in which at least two operation members of the operation members have been operated within a predetermined period of time; and a movement controller prohibiting, in a controlled manner, a spatial movement of the arm unit when the determination unit determines that the operation at the plurality of operation members corresponds to the improper state.
For making the arm unit holding the medical device movable, it is required for an operator to operate at least two predetermined operation members among a plurality of operation members secured on an operation unit. Only when a properly operated state is established where the “at least two operation members” are operated within a predetermined period of time (for example, a few seconds), the operator is allowed to move the arm unit, so that the arm unit can be moved to spatially move the medical device such as endoscope at operator's will.
However, the operator's operation is in the improper state deviating from the “properly operated state,” the arm unit is not allowed to move. In other words, the medical device is not allowed to move spatially; of course, cannot be moved at operator's will. Hence the medical device is obliged to keep its locked (fixed) state at the same spatial position. The “improper state” includes an “improperly operated state,” in which an operator has not operated the foregoing “at least two operation members” within a predetermined period of time; an “accidentally operated state,” in which only part of the foregoing “at least two operation members” is operated due to, for example, a push from any obstacle; and a “malfunctioning state,” in which a signal resulting from operational failures of the operation unit is outputted from the operation unit, the signal showing a situation where only part of the foregoing “at least two operation members” is operated. Incidentally, though the states deviating from the “properly operated state” includes a “non-operated state,” but this is omitted from the explanations in the present invention, because such a state does not relate to the movement of the arm unit any longer.
As another aspect of the present invention, there is provided an apparatus for holding a medical device, comprising: an arm unit spatially holding the medical device; an electric driver spatially moving the medical device and being secured to the arm unit; an operation unit equipped with a plurality of operation members to be operated by an operator to control a spatial movement of the medical device; a determination unit determining whether or not an operator's operation at the plurality of operation members corresponds to an improper state deviating from a properly operated state in which at least two operation members of the operation members have been operated within a predetermined period of time; and an electric operation controller prohibiting the electric driver from being operated in a controlled manner, in cases where it is determined by the determination unit that the operation is in the improper state. Hence the improper states (i.e., the improperly operated state, accidentally operated state, and malfunctioning state) are found to prohibit the operations of the electronic driver, resulting in that the medical device is locked from its spatial movement.
Still, as another aspect of the present invention, there is provided a method for holding a medical device to be spatially movable, the medical device being held by an arm unit by allowing an operator to operate a plurality of operation members, the method comprising steps of: determining whether or not an operator's operation at the plurality of operation members corresponds to an improper state deviating from a properly operated state in which at least two operation members of the operation members have been operated within a predetermined period of time; and prohibiting, in a controlled manner, a spatial movement of the arm unit when it is determined that the operation at the plurality of operation members corresponds to the improper state. This holding method also copes with the forgoing improper states in the same way as the above.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1 is a perspective view showing the configuration of a medical-device holding apparatus according to a first embodiment of the present invention;
FIG. 2 is a side view, partly sectioned, showing a holder employed by the holding apparatus in the first embodiment;
FIG. 3 is a block diagram of hardware elements of a controller employed by the holding apparatus in the first embodiment;
FIG. 4 is a functional block diagram of the controller employed by the holding apparatus in the first embodiment;
FIG. 5 is a flowchart showing the operations of the controller;
FIG. 6 is a perspective view showing a holder employed by a medical-device holding apparatus in a second embodiment according to the present invention;
FIG. 7 is a flowchart showing the operations performed by a controller in the second embodiment;
FIG. 8 is a perspective view showing a medical-device holding apparatus in a third embodiment according to the present invention;
FIG. 9 shows a block diagram of an electric field-of-view driver according to the third embodiment;
FIG. 10 illustrates a block diagram of a control circuit according to the third embodiment; and
FIG. 11 is a perspective view indicating a holder adopted by a medical-device holding apparatus according to a modification directed to the third embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Various embodiments of medical-device holding apparatuses according to the present invention will now be described with reference to the accompanying drawings.
First Embodiment
Referring to FIGS. 1-5 , a medical-device holding apparatus according to a first embodiment will now be described.
As shown in FIG. 1 , the medical-device holding apparatus is provided with a support base 11 , a polyarticular arm 12 whose one end is attached to the support base 11 , and a holder 13 sustained at the other end of the polyarticular arm 12 .
The support base 10 is detachably attached to an attaching member, such as floor or patient bed. The polyarticular 12 is provided with three arms consisting of first to third arms 12 a - 12 c, three joints 13 a - 13 c arranged at one end of the first arm 12 a , between the first and second arms 12 a and 12 b , and between the second and third arms 12 b and 12 c , respectively, and a ball joint attached to the top of the third arm 12 c . Therefore, on the support base 10 , the arms 12 a , 12 b , and 12 c are connected to each other in this order so that the arms 12 a - 12 c can be moved rotatably in the three-dimensional space via the joints 13 a , 13 b , and 13 c . In addition, a pillar 15 is suspended from the ball joint 14 attached to the headmost arm 12 c , and a holder 13 to which a medical device is held is secured to the pillar 15 .
The ball joint 14 incorporates a known fluid clutch 28 d (refer to FIG. 3 ) that uses fluid, such as air, as a pressure transmission medium. The fluid clutch 28 d is electrically connected to a control box 16 composing as control means and responds to a command from the control box 16 in such a manner that a clutch portion (i.e. a brake not shown) of the fluid clutch 28 d are selectively controlled between two states of being clutched and non-clutched. The clutch portion connects both the pillar 15 (that is, the holder 13 ) and the third arm 12 c . Thus, when the clutch portion is in its clutched state, the pillar 15 (holder 13 ) is positionally fixed to the third arm 12 c (i.e., positionally fixed). In contrast, in cases where the clutch portion is in its non-clutched state, the pillar 15 (i.e., the holder 13 ) will not be positionally fixed to the third arm 12 c , and can be moved freely. To be short, the fluid clutch 28 d responds to the existence and non-existence of fluid pressure to be supplied so that the holder 13 is positionally fixed to the ball joint 14 or positionally released from being fixed to the ball joint 14 in a selective manner.
As described, the holder 13 is coupled with the third arm 12 c via the ball joint 14 with the fluid clutch 28 d , and can be rotated and moved with suspending from the third arm 12 c under the fluid clutch 28 d is unclutched (i.e., released).
The fluid clutches 28 a - 28 c (refer to FIG. 3 ) employing fluid such as air and having the similar construction and function are incorporated in the joints 13 a - 13 c , respectively, and can selectively be switched between their clutched or non-clutched states in answer to a control signal from the control box 16 . The fluid clutches 28 a - 28 c are constructed to release the clutch portion in response to an application of pressure. In such a control manner, the first arm 12 a is able to selectively realize the position-fixed state or position-free state to the support base 11 , the second arm 12 b to the first arm 12 a , and the third arm 12 c to the second arm 12 b.
On the headmost end of the holder 13 , as shown in FIGS. 1 and 2 , an endoscope 17 serving as one of medical devices to treat and observe the inside of a patient to be examined is detachably loaded and supported. In FIG. 1 , a reference P depicts a patient to be observed and treated and by the endoscope 17 .
By way of example, the holder 13 is formed into a cuboid-like member having a specific thickness and a section perpendicular to its longitudinal axis formed into a rectangle. This holder 13 , which can be grasped by a user, has switches loaded thereto which can be operated by the user. The size of the cuboid-like member is set to an appropriate amount which makes it possible that the user grasps the member well.
On a base-side end of the holder 13 , one end of the foregoing pillar 15 is secured, while at the head-side end, a loading hole is formed therethrough. The endoscope 17 is loaded in the loading hole in a detachable manner.
On upper and lower surfaces of the holder 13 are formed a first switch and a second switch 18 and 19 , which serve as input means of operation signals, consist of microswitches, respectively. The upper and lower surfaces are defined as upward and downward surfaces of the holder 13 when an operator can grasp the holder 13 from a direction which makes the endoscope 17 downward, as shown by a chain double-dashed line W in FIG. 2 .
The first and second switches 18 and 19 are formed to provide switch signals to the control box 16 through lead wires respectively connecting to the control box 16 . As will be described later, the control box 16 has the configuration that uses the switch signals to produce control signals in which the states indicated by the switch signals are reflected, the control signals being fed to the fluid clutch 28 d of the ball joint 14 and the fluid clutches 28 a - 28 c of the joints 13 a - 13 c.
The structures of the first and second switches 18 and 19 will now be described. As illustrated in FIG. 2 , the first and second switches 18 and 19 are embedded in two locations of the holder 13 ; to be specific, when a user grasps the holder 13 , one switch 18 is located close to the holder near to an endoscope-loading region of the holder 13 , that is, a head-side given position of the holder 13 to which the thumb is approximately touched on the upper surface and the other switch 19 is located at a given position of the holder 13 to which the first finger is approximately touched on the lower surface. The first switch 18 is embedded to have its operating portion opened from the upper surface, whilst the second switch 19 is embedded to have its operating portion opened from the lower surface.
More specifically, a first and second concave switch accommodating rooms 20 and 21 are formed at given positions of the holder 13 , which are close to the head thereof. These accommodating rooms 20 and 21 are formed to provide their main opening opened from the upper and lower surfaces of the holder 13 , but are slightly positionally shifted with each other in a longitudinal direction of the holder 13 . In the first and second concave switch accommodating rooms 20 and 21 , the first and second switches 18 and 19 are accommodated with their operating directions upside down with each other. Specifically, in FIG. 2 , the operating direction to the first switch 18 is a downward direction and that to the second switch 19 is an upward direction. The lead wires of the fist and second switches 18 and 19 are electrically coupled to the control box 16 , respectively.
Of the above switch accommodating rooms 20 and 21 , the first switch accommodating room 20 accommodates the first switch 18 together with a switch lever 22 and a hinge 23 , where the switch lever 22 faces the first switch 18 to freely rotate thanks to the hinge 23 . To the switch lever 22 is provided a pushing force via a first spring member 24 in the clockwise in FIG. 2 (corresponding to a direction that turns the first switch 18 “on”). This first spring member 24 has a base portion engaging with a tip of an operation-force-amount adjusting member 25 in an adjustable fashion. This adjusting member 25 has a middle portion held by holder 13 in a screw-adjustable manner and a base portion to which an operating portion 26 is secured so that the operating portion 26 can be operated. The operating portion 26 is located to protrude from the lower surface of the holder 13 . Accordingly, rotating the adjusting member 25 makes the adjusting member 25 itself advance against the first spring member 24 , whereby the pushing force of this first spring member 24 can be adjusted. An amount of force required to operate the switch lever 22 can be adjusted.
As shown in FIG. 3 , each of the foregoing fluid clutches 28 a - 28 d is coupled with an electromagnetic valve 29 via a duct PG. The electromagnetic valve 29 is coupled with a fluid-pressure source 29 a , which is for example a gas container placed in an operation room. Hence, responsively to the open and close of the electromagnetic valve 29 , the fluid of a given pressure (e.g., air) is supplied to the fluid clutches 28 a - 28 d , respectively, from the fluid-pressure source 29 a.
As shown in FIG. 3 , the control box 16 is provided with a CPU 30 , in which processing on software executed by the CPU 30 provides desired calculation functions. The calculation part of the control box 16 , however, is not always limited to the computer configuration that uses the CPU, but may be configured into a hardware construction that provides desired functions using logic circuits such as AND and OR circuits.
The control box 16 according to the present embodiment is provided with, besides the CPU 30 , peripheral devices including a ROM 31 , RAM 32 , clock circuit 33 , input interface 34 , and output interface 35 , a D/A converter 36 connected to the output interface 35 , and a driver 37 . In the ROM 31 , programs are stored in advance, which are computer-readable and define procedures of calculation for control of the clutches which will be described later. When the CPU 30 is activated, it therefore reads in the programs from the ROM 31 , and executes calculation in sequence based on the procedures defined by the read-in programs. The RAM 32 is a memory temporarily used during the calculation of the CPU 30 . The clock circuit 33 is placed to provide a reference clock signal to the CPU 30 .
Connected to the input interface 34 are the first and second switches 18 and 19 , so that on/off information from the switches 18 and 19 is transmitted to the CPU 30 . A control signal produced through the calculation executed by the CPU 30 is sent to the D/A converter 36 via the output interface 35 , thereby being subject to D/A conversion. The resultant control signal is amplified by the driver 37 , and then supplied to the electromagnetic valve 29 .
The control box 16 is also provided with, as information means, a buzzer 38 and an LED 39 , which are connected to the CPU 30 .
Calculating functions realized by the CPU 30 can be depicted as shown in FIG. 4 . Concretely, with its software processing, the CPU 30 is able to present the functions for a switch detection circuit “A,” determination circuit “B,” and drive/control circuit “C.”
Of these functions, the switch detection circuit “A” detects the on/off states of the first and second switches 18 and 19 , and operates on the basis of the detected results such that it outputs an “on” signal to the drive/control circuit “C,” only when both the first and second switches 18 and 19 are turned “on” almost simultaneously (that is, at the same time or within a predetermined period of time). Responsively to the “on” signal, the drive/control circuit “C” outputs a drive signal to open the electromagnetic valve 29 . When the electromagnetic valve 29 is opened, fluid pressure is applied from the fluid-pressure source 29 a to the fluid clutches 28 a , 28 b , 28 c and 28 d , thus releasing the fluid clutches 28 a - 28 d . As a result, the joints 13 a - 13 c and boll joint 14 presents their position-free states, that is, released states from their position-fixed states.
Meanwhile, in cases where, of the first and second switches 18 and 19 , either one switch is turned “on” over a predetermined period of time or more, the determination circuit “B” determines that either one switch has been pressed alone, and provides no control signal with the drive/control circuit “C” (i.e., “off” state). That is, the electromagnetic valve 29 becomes its closed sate or keeps its closed state. In this closed state of the electromagnetic valve 29 , no fluid pressure is applied from the fluid-pressure source 29 a to the fluid clutches 28 a - 28 d , with the result that fluid clutches 28 a - 28 d are kept clutched, whereby the joints 13 a - 13 c are kept locked (i.e., in their position-fixed states).
The determination circuit “B” has a timer function (realized by a timer BT in FIG. 4 ) in order to measure a state where either the first or second switch 18 or 19 solely becomes “on” over a predetermined period of time or more.
Referring to FIG. 5 , practical procedures of calculation on the software processing executed by the CPU 30 will now be described.
The CPU 30 determines, at step S 1 , whether or not the first switch 18 is in the “on” state. If the determination is NO (that is, the first switch 18 is in the “off” state), the processing in the CPU 30 proceeds to step S 2 , whereat the CPU 30 determines whether or not the second switch 19 is in the “on” state. When the determination is NO (that is, the second switch 19 is in the “off” state), the CPU 30 makes the processing to proceed to step S 3 , where the CPU 30 commands the electromagnetic valve 29 to be or kept “off.” The processing is then made to advance to steps S 4 -S 6 in sequence, where the CPU 30 commands the buzzer 38 to be or kept “off” (step S 4 ), commands the LED 39 to be or kept “off” (step S 5 ), and commands the timer BT to initialize its count (step S 6 ). Then the processing returns to step S 2 .
In addition, when it is determined “YES” at step S 1 , the CPU 30 makes the processing to step S 7 , whereat it is further determined whether or not the second switch 19 is in the “on” state. If the determination at step S 7 is “YES,” the processing is shifted to step S 8 to allow the electromagnetic valve 29 to be or kept “on.” The processing is then made to advance to steps S 9 -S 11 in sequence, where the CPU 30 commands the buzzer 38 to be or kept “off” (step S 9 ), commands the LED 39 to be or kept “off” (step S 10 ), and commands the timer BT to initialize its count (step S 11 ). Then the processing returns to step S 2 .
Moreover, in cases where it is determined “yes” at step S 2 or “no” at step S 7 , the processing in the CPU 30 is shifted to step S 12 , where it is determined whether or not the timer BT is in operation. The determination at step S 12 reveals the timer BT is not in operation (NO), the processing is shifted to step S 13 to cause the timer BT to start its count operation. The processing at step S 14 is then executed to allow the electromagnetic valve 29 to be “off.” Further, at step S 15 , the buzzer 38 is made or kept “off,” and then, at step S 16 , the LED 39 is made or kept “off,” before returning to step S 1 .
In the case that the determination at step S 12 is YES, that is, it is determined at step S 12 if the timer BT is in operation or not, the CPU 30 shifts its operation to step S 17 , where it is determined if or not the timer BT has counted a predetermined period of time (for example, 3 seconds) or more. If YES at step S 17 , the processing at steps S 18 , S 19 , and S 20 is executed in turn. Specifically, the electromagnetic valve 29 is brought into or kept “off” (step S 18 ), the buzzer 38 is turned or kept “on” (step S 19 ), and then the LED 39 is turned or kept “on” (step S 20 ), before returning to step S 2 .
In contrast, when it is determined NO at step S 17 , the processing at steps S 14 -S 16 is executed by the CPU 30 as described above. To be specific, the electromagnetic valve 29 is made or kept “off” (step S 14 ), the buzzer 15 is made or kept “off” (step S 15 ), and the LED 39 is made or kept “off” (step S 16 ).
Accordingly, through the foregoing processing conducted by the CPU 30 , the control signal supplied to the electromagnetic valve 29 is kept “off,” when either the first or second switch 18 or 19 is turned “on” solely. The electromagnetic valve 29 thus keeps its closed valve state, which keeps the clutched states of the fluid clutches 28 a , 28 b , 28 c and 28 d . Since the joints 13 a , 13 b and 13 c are positionally kept locked (clutched), the polyarticular arm 12 is also positionally kept locked, so that the endoscope 17 is positionally fixed (i.e. the position-fixed state).
In addition, during the position-fixed state being kept, the system is able to cope with an operator's operation that only either the first or second switch 18 or 19 is turned “on” and the “on” state lasts for a predetermined period of time (in the present embodiment, three seconds). Even if such an operation is carried out, the foregoing locked state of the polyarticular arm 12 is kept, while the buzzer 38 honks and the LED 39 flashes. Thus the operator is able to steadily know that the medical-device holding apparatus has failed to release its locked state (i.e., position-fixed state), which requires succeeding necessary operations such as unlocking re-operation. Hence the operator's operation can be smoothened.
Additionally, in cases where the endoscope 17 or polyarticular arm 12 is moved to rotate during a surgical operation, it may happen that the drape is pulled to accidentally push either the first or second switch 18 or 19 . It may also happen that such a rotary operation involves an interference with other devices which may cause only either the first or second switch 18 or 19 to be turned “on” by mistake. Even such situations are caused, the foregoing information means immediately informs the operator of the currently operated state, thereby alleviating the operator from anxiety that the operator should take care of operations at all times. This reduces an operator's burden on the operations.
By the way, the exemplified processing shown in FIG. 5 , which is executed by the CPU 30 , can further be modified with regard to, for example, the order of on/off determinations for the first and second switches 18 and 19 . The second switch 19 may be subjected to the on/off determination, before that for the first switch 18 . With regard to the buzzer 38 and LED 39 serving as the information means, only one of the buzzer 38 and LED 39 may be employed.
Further, a period of time to be measured by the timer at step S 17 cannot always be limited to 3 seconds, but may be a minimum period of time which can sense steadily the state in which “either the first or second switch 18 or 19 is “on”-operated alone. In other words, such a period of time can be defined as a time interval for measuring simultaneity for operator's operations. Hence, for example, an appropriately selected period of time, such as 1 second, 2 seconds, or 4 seconds, can be adopted, depending on design conditions or other necessary factors.
Moreover, as described, in the processing shown in FIG. 5 conducted by the CPU 30 , the detection is made to recognize the state both the first and second switches 18 and 19 are operated “on” and a span of time from the “on” operation at one switch 18 ( 19 ) to that at the other switch 19 ( 18 ) is within a predetermined period of time. This manner of detection can be applied to detection of malfunctioning states of either the first or second switch 18 or 19 . For example, in cases where either switch is in fault condition due to a fusion-bonded switch contact, the processing shown in FIG. 5 can also be used for detecting the malfunction. In order to achieve this, the CPU 30 is set to execute the processing shown in FIG. 5 at specific intervals (for example, at intervals of a few minutes or at a time when the apparatus is activated). Hence, when either the first or second switch 18 or 19 is out of order (in other words, no operation is made but the switch is in the “on” state), this state is detected, resulting in that the buzzer 38 honks and the LED 39 flashes. Using an LED dedicated to this detection, which is different from the LED 39 designated as means to inform the foregoing improperly operated states or accidentally operated states, makes it easier for an operator to immediately recognize the malfunctioning states of the various switches. In this case, of course, either one of the buzzer and LED can be used as informing means.
Moreover, signals to be detected at steps S 1 , S 2 and S 7 in FIG. 5 are not be limited to signals from the first and second switches 18 and 19 , but may be signals from electric circuits electrically connected to these switches, respectively. For instance, in a configuration where a relay is arranged to each of the first and second switches 18 and 19 to provide a switch signal via each relay, a signal outputted from each relay can be an object to be detected. Thus, the object to be detected can be developed to peripheral circuits of the switches, such as relay whose contact is fusion-bonded, which may not be confined to the detection of malfunction of the switch itself. This way of detection can raise reliability for the arm-move prohibiting control.
Second Embodiment
Referring to FIGS. 6 and 7 , a second embodiment of the medical-device holding apparatus according to the present invention will now be described. In the second and subsequent embodiments, the configuration elements identical or similar to those in the first embodiment will be referred by the same reference numerals for the sake of simplified or omitted explanations.
The configurations in the second embodiment differ from those in the first embodiment in the shape of the holder 13 and the locations of the first and second switches disposed in the holder 13 . In addition, a further difference from the first embodiment is how to escape from a locked state where the joints are locked due to the fact that either the first or second switch is alone operated for a predetermined period of time or more.
As shown in FIG. 6 , in order that the fluid clutches in the joints of the polyarticular arm 12 (arms 12 a - 12 c ) have clutched and unclutched in a selective manner, there are provided two operation switches 3 a and 3 b mounted on the holder 13 handled for moving the endoscope 17 . The two operation switches 3 a and 3 b are arranged on both sides of the plate-like holder 13 in such a manner that they are located at the same position in the longitudinal direction of the holder 13 . The LED 39 is mounted on the endoscope-side tip of the holder 13 . Incidentally, in the present embodiment, the buzzer is omitted from being arranged. When an operator such as surgeon holds grips the holder 13 to press the two operation switches 3 a and 3 b by the thumb and first finger at the same time (simultaneously or almost simultaneously), the fluid clutches operates to release the fixed state of each joint (i.e., unclutched). Thus as long as the two operation switches 3 a and 3 b are not pressed at the same time or within a predetermined period of time, each joint will not be from its clutched state.
In this medical-device holding apparatus, it may happen that rotating the endoscope 17 or arms 12 a - 12 c during a surgical operation causes the drape to be tightened or an interference with other equipments, so that the operation switches 3 a and 3 b are pressed by mistake. To prevent such situations, the CPU 30 executes the processing according to the flowchart shown in FIG. 7 .
That is, at step S 21 in FIG. 7 , it is determined whether or not one operation switch 3 a , of the two operation switches 3 a and 3 b , is in “on.” When this determination shows NO, the processing is shifted to step S 22 , where the other operation switch 3 b is subjected to the determination whether or not it is made “on.” If the determination at step S 22 is NO, the processing goes to step S 23 to turn or keep the electromagnetic valve 29 “off.” Further, the processing is performed at step S 24 to turn or keep the LED 39 “off” and, at step S 25 , to initialize the timer BT, before returning to step S 21 .
Meanwhile when it is determined YES at step S 21 , the processing is shifted to step S 26 , where the determination switch 3 b is subjected to the determination whether or not it is made “on.” The determination of YES allows the processing to be performed at step S 27 , where the electromagnetic valve 29 is made or kept “on.” Then at step S 28 , the LED 39 is made or kept “off,” and at step S 29 , the timer BT is initialized, before being shifted to step S 21 .
In the case of the determination of YES at step S 22 or NO at step S 26 , the processing is shifted to step S 30 , where it is determined whether or not the timer BT is in operation. If the determination is NO (not in operation), the processing at steps S 31 to S 33 is carried out in sequence. The timer BT is started to count the time (step S 31 ), the electromagnetic valve 29 is kept “off” (step S 32 ), and the LED 39 is kept “off” (step S 33 ). Then the processing is made to return to step S 21 .
On the other hand, if it is determined “YES” at step S 30 , that is, it is found that the timer BT is in operation, the processing is shifted to step S 34 to further determine whether or not the count of the timer BT shows three seconds (i.e., a predetermined period of time) or more. If the determination at step S 34 is YES, i.e., a period of 3 seconds or more is counted, the processing is carried out such that the electromagnetic valve 29 is in its “off” state (step S 35 ) and the LED 39 is turned “on” (step S 36 ). The processing is then shifted to step S 37 to determine whether or not the operation switches 3 a and 3 b both are in their “off” states. If this determination is NO, this termination processing is repeated to wait for a situation where the operation switches 3 a and 3 b both become “off.” When both the switches 3 a and 3 b are released from being pushed (the determination at step S 37 is YES), the processing escapes from the repeated determinations at step S 37 . The CPU 30 returns the processing to step S 21 .
When the determination at step S 34 is NO (i.e. a predetermined period of 3 seconds or more has yet to come), the processing at steps S 32 and S 33 is performed as described before.
As a result of the foregoing processing, when either one of the operation switches 3 a and 3 b attached to the holder 13 is made “on” and its “on” state lasts for the predetermined period of time (e.g., 3 seconds in the present embodiment, but not limited to this period of time), the electromagnetic valve 29 becomes “off.” The arms 12 a - 12 c are therefore locked to not allow any moves thereof. At the same time, the LED 39 is turned “on” to notify the surgeon (i.e., operator) that the current operation toward the switches is improper. This locked state can be released only when the switches 3 a and 3 b both are made “off,” thanks to the processing at step S 37 in FIG. 7 .
Third Embodiment
Referring to FIGS. 8-10 , a third embodiment of the medical-device holding apparatus according to the present invention will now be described.
As shown in FIG. 8 , a holder 204 , which holds endoscope 17 , is attached to the head-side arm 12 a via the ball joint 14 . To the holder 204 is attached an electric view-change driver 204 a which will be described later, which is in charge of changing an observing direction of the endoscope 17 by selectively moving it in the X-axis, Y-axis and Z-axis directions. The electric view-change driver 204 a is eclectically connected to a foot switch box 206 via a control box 205 .
Using FIGS. 9 and 10 , the holder 204 , control box 205 , and foot switch box 206 will now be described.
The control box 205 is provided with, in addition to the foregoing electromagnetic valve 29 , a switch detection circuit 207 and a motor control circuit 208 , wherein the switch detection circuit 207 is electrically connected to the electromagnetic valve 29 . Additionally, electrically connected to the switch detection circuit 207 are a joystick switch 209 and a drive switch 210 , which are equipped in the footswitch box 206 . The joystick switch 209 is provided with a four-way switch which operates to move the endoscope 17 in the upward, downward, and lateral directions. By way of example, the switch detection circuit 207 is functionally configured with the aid of the software processing carried out by a CPU, like the foregoing control box in the first embodiment.
The holder 204 is provided with the foregoing first and second switches 18 and 19 and an LED 211 , which are electrically connected with the switch detection circuit 207 . The holder 204 is also provided with an X-axis motor 212 , Y-axis motor 213 , and Z-axis motor 214 , which are all electrically coupled with the motor control circuit 208 . Operator's operations at the joystick switch 209 allow the motor control circuit 208 to drive the X-, Y- and Z-axes motors 212 , 213 and 214 mounted in the holder 204 concurrently or selectively so that the view of the endoscope 17 can be moved in a controlled manner.
The electric view-change driver 204 a is structured as schematically shown in FIG. 9 , in which there are provided with an X-axis housing 212 a , Y-axis housing 213 a , Z-axis housing 214 a . The X-axis housing 212 a is arranged to engage with an X-axis motor 212 with a motor shaft having a pinion gear 215 at one end thereof. This pinion gear 215 is engaged with an X-axis rack 215 a slidably formed on the X-axis housing 212 a in the X-axis direction.
The Y-axis housing 213 a is mounted on the X-axis rack 215 a . The Y-axis housing 213 a is arranged to engage with a Y-axis motor 213 with a motor shaft having a pinion gear 216 at one end thereof. This pinion gear 216 is engaged with a Y-axis rack 216 a slidably formed on the Y-axis housing 213 a in the Y-axis direction.
Moreover, the Z-axis housing 214 a is mounted on the Y-axis rack 216 a . The Z-axis housing 214 a is arranged to engage with a Z-axis motor 214 with a motor shaft having a pinion gear 217 at one end thereof. This pinion gear 217 is engaged with a Z-axis rack 217 a slidably formed on the Z-axis housing 214 a in the Z-axis direction. This Z-axis rack 217 a finally holds the endoscope 17 , as illustrated in FIG. 9 .
Thus, a surgeon (operator) can grip the holder 204 to push down the first and second switches 18 and 19 , for example, by the thumb and first finger at the same tame or within a predetermined period of time. This push activates, with the aid of the switch detection circuit 207 , the electromagnetic valve 29 to release the fluid clutch of each joint from being clutched. In contradiction to this, in the remaining cases where the first and second switches 18 and 19 are not pushed down at the same time or within the predetermined period of time, unlike the above, the switch detection circuit 207 will not permit each joint to be released from being fixed. Of course, when only one of the two switches 18 and 19 is continuously made “on” the predetermined period of time (e.g., 3 seconds) or more, the switch detection circuit 207 will issue a signal to light up the LED 211 in order to inform the operator about the improper operation, which is similar to that in the second embodiment.
This control for the operator's operations at the two switches 18 and 19 may be realized in the same or similar way as or to the processing based on the flowchart shown in FIG. 5 or 7 , which can be assigned to the control box 205 .
The joystick switch 209 on the footswitch box 206 is operated to decide a direction, information indicative of the decided information being displayed on a monitor M as shown in FIG. 8 . After the decision of this direction, the drive switch 210 is turned “on,” so that the electric view-change driver 204 a is driven in response to this instruction. And as long as the joystick switch 209 is operated within a predetermined period of time (for example, 5 seconds) starting from the switch “on” of the drive switch 210 , that is, both the switches 209 and 210 are operated (“on”) within the predetermined period of time in the similar manner to the forgoing, the switch detection circuit 207 and motor control circuit 208 jointly operate to instruct the electric view-change driver 204 a to drive the X-, Y- and Z-axis motors 212 , 213 and 214 .
However, in the case that only either one of the joystick switch 209 and drive switch 210 is operated (“on”) continuously the predetermined period of time or more, a signal from the switch detection circuit 207 will cause the LED 211 to light to inform an operator of this improper operation. Concurrently, the X-, Y- and Z-axes motors 212 - 214 in the electric view-change driver 204 a are locked not to be driven, whereby the view will be prohibited from being changed.
This control for the operator's operations at both the joystick switch 209 and the drive switch 210 can also be performed in the same manners as above based on based on the flowchart shown in FIG. 5 or 7 , which can be assigned to the control box 205 .
(Modifications)
FIG. 11 shows a modification of the third embodiment, wherein the holder 204 is provided with both the joystick switch 209 and drive switch 210 . Hence an operator can grip the holder 204 , during which time the operator operates both the switches 209 and 210 . In this modification, there is no necessity of employing the footswitch box 206 , thus simplifying the switch constructions.
In addition, though the foregoing various embodiments have been described about the construction in which the endoscope serving as the medical device is employed, however, this is not a definitive list. Any other types of medical treatment devices can be used as a medical device, so that the similar advantages to the foregoing can be provided.
In each of the foregoing embodiments, the polyarticular arm consisting of three joints has been described, but the number of joints is not confined to three. The polyarticular arm having a desired number of joints can be applied to the present invention to enjoy the foregoing advantages which are characteristic of the present invention.
Although the description above contains many specificities, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of the present invention. Thus the scope of the present invention should be determined by the appended claims. For example, in the third embodiment, the control for locking the electric view-change driver may be reduced in practice solely, separately from the control for lock and unlocking the polyarticular arm. | An apparatus for holding a medical device has an arm unit equipped with, for example, a polyarticular arm, which holds the medical device such as endoscope movably in the space. Additionally to a determination unit and a controller, the holding apparatus has an operation unit equipped with a plurality of operation members with which an operator's operation causes the arm unit to be moved spatially. The determination unit determines whether or not operator's operations at the plurality of operation members corresponds to an improper state deviating from a properly operated state in which at least two predetermined operation members have been operated within a predetermined period of time which is set to measure simultaneity for operations. If it is determined that the operation is in the improper state, the controller prohibits the arm unit from moving. As long as the operation is proper, the arm unit can be moved. | 0 |
RELATED APPLICATIONS
[0001] This patent application claims priority from U.S. Provisional Application No. 61/875,439 filed Sep. 9, 2013, entitled, “UNSUPERVISED BEHAVIOR LEARNING SYSTEM AND METHOD FOR PREDICTING PERFORMANCE ANOMALIES IN DISTRIBUTED COMPUTING INFRASTRUCTURES,” and U.S. Provisional Application No. 61/876,097 filed Sep. 10, 2013, entitled, “UNSUPERVISED BEHAVIOR LEARNING SYSTEM AND METHOD FOR PREDICTING PERFORMANCE ANOMALIES IN DISTRIBUTED COMPUTING INFRASTRUCTURES,” the disclosures of which are incorporated herein, in their entirety, by reference.
STATEMENT OF GOVERNMENT INTEREST
[0002] This invention was made with government support under Contract No. 550816, awarded by the U.S. National Science Foundation, and Contract No. 552318, awarded by the U.S. Army Research Office. The government has certain rights in the invention.
BACKGROUND
[0003] The present invention relates to unsupervised behavior learning and anomaly prediction in a distributed computing infrastructure. In one particular example, the invention is implemented in an Infrastructure-as-a-Service (“IaaS”) cloud system.
[0004] IaaS cloud systems allow users to lease computing resources in a pay-as-you-go fashion. In general, a cloud system includes a large number of computers that are connected through a real-time communication network (e.g., the Internet, Local Area Network, etc.) and can run numerous physical machines (“PMs”) or virtual machines (“VMs”) simultaneously. A VM is a software-based implementation of a computer that emulates the computer architecture and functions of a real world computer. Due to their inherent complexity and sharing nature, cloud systems are prone to performance anomalies due to various reasons such as resource contentions, software bugs, and hardware failures. It is difficult for system administrators to manually keep track of the execution status of tens of thousands of PM or VMs. Moreover, delayed anomaly detection can cause long service delays, which is often associated with a large financial penalty.
[0005] Predicting and detecting anomalies, faults, and failures is of interest to the computing community as the unpredicted or surprise failure of a computing system can have numerous negative impacts. Broadly, contemplated approaches of failure prediction can include supervised learning methods and unsupervised learning methods. Supervised learning methods rely on labeled training data to accurately identify previously known anomalies. Unsupervised learning methods do not require labeled training to identify anomalies. These methods can be further divided into anomaly detection schemes and anomaly prediction schemes. Anomaly detection schemes identify a failure at the moment of failure, while anomaly prediction schemes try to predict a failure before it occurs.
SUMMARY
[0006] Some embodiments of the invention provide an unsupervised behavior learning (“UBL”) system for predicting anomalies in a distributed computing infrastructure, which in one embodiment is a virtualized cloud computing system that runs application VMs. The system uses an unsupervised learning method or technique called Self Organizing Map (“SOM”) to capture the patterns of normal operation of all the application VMs. The unsupervised learning method does not require labeled training data. To predict anomalies, the system looks for early deviations from normal system behaviors. Upon predicting an anomaly, the system can provide a warning that specifies the metrics that are the top contributors to the anomaly.
[0007] Other embodiments of the invention provide a method of predicting performance anomalies in a distributed computing infrastructure, which in one embodiment is a virtualized cloud system, with unsupervised behavior learning. The method begins with a behavior learning phase. In the behavior learning phase, the method develops a model of normal and anomalous behavior of the system with a SOM training process that does not require labeled training data. Next, the method proceeds into a performance anomaly prediction phase. In the performance anomaly prediction phase, the method receives and compares real-time data with the SOM to determine if the system's current behavior is normal or anomalous. The method predicts a future system failure when numerous consecutive samples of real-time data indicate anomalous system behavior. Upon predicting a system failure, the method proceeds into performance anomaly cause inference phase. In the performance anomaly cause inference phase, the method identifies a ranked set of system-level metrics which are the top contributors to the predicted system failure. The method raises an alarm that includes the ranked set of system-level metrics.
[0008] In addition, certain embodiments of the invention provide a method of predicting performance anomalies in a first computer machine in a distributed computing infrastructure with a second computer machine using unsupervised behavior learning. The method includes generating, by the second computer machine, a model of normal and anomalous behavior for the first computer machine based on unlabeled training data; acquiring, by the second computer machine, real-time data of system level metrics for the first computer machine; and determining, by the second computer machine, whether the real-time data is normal or anomalous based on a comparison of the real-time data to the model. The method also includes predicting, by the second computer machine, a future system failure of the first computer machine based on multiple consecutive comparisons of the real-time data to the model. Upon predicting a future system failure, the second computer machine generates a ranked set of system-level metrics which are contributors to the predicted system failure of the first computer machine, and generates an alarm that includes the ranked set of system-level metrics.
[0009] The act of generating a model of normal and anomalous behavior may include generating a self-organizing map.
[0010] In still another embodiment or aspect, the invention provides an unsupervised behavior learning system for predicting anomalies in a distributed computing infrastructure. The distributed computing infrastructure includes a plurality of computer machines. The system includes a first computer machine and a second computer machine. The second computer machine is configured to generate a model of normal and anomalous behavior of the first computer machine, where the model is based on unlabeled training data. The second computer machine is also configured to acquire real-time data of system level metrics of the first machine; determine whether the real-time data is normal or anomalous based on a comparison of the real-time data to the model; and predict a future failure of the first computer machine based on multiple consecutive comparisons of the real-time data to the model. Upon predicting a future failure of the first computer machine, generate a ranked set of system-level metrics which are contributors to the predicted failure of the first computer machine, and generate an alarm that includes the ranked set of system-level metrics. The model of normal and anomalous behavior may include a self-organizing map.
[0011] Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 illustrates a distributed computing infrastructure.
[0013] FIG. 2 illustrates a process for operating the UBL system in FIG. 1 to predict performance anomalies.
[0014] FIG. 3 illustrates a process for operating the UBL system in FIG. 1 to perform behavior learning.
[0015] FIG. 4 illustrates a process for operating the UBL system in FIG. 1 to update a SOM.
[0016] FIG. 5 illustrates an exemplary iteration of the process in FIG. 4 .
[0017] FIG. 6 illustrates a process for operating the UBL system in FIG. 1 to perform performance anomaly prediction.
[0018] FIG. 6 illustrates a process for operating the UBL system in FIG. 1 to perform performance anomaly prediction.
[0019] FIG. 7 illustrates an exemplary system failure of the UBL system in FIG. 1 .
[0020] FIG. 8 illustrates an exemplary SOM model after the behavior learning phase.
[0021] FIG. 9 illustrates an exemplary SOM model after the behavior learning phase.
[0022] FIG. 10 illustrates a process for operating the UBL system in FIG. 1 to perform anomaly cause inference.
DETAILED DESCRIPTION
[0023] Before any embodiments and aspects of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the examples provided, the embodiments discussed, or to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.
[0024] Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. A plurality of hardware and software based devices, as well as a plurality of different structural components may be utilized to implement the invention.
[0025] A distributed computing infrastructure includes a large number of computers that are connected through one or more communications networks, such as a real-time communications networks. FIG. 1 illustrates an exemplary distributed computing infrastructure 10 that includes, among other components, a first computer machine 12 , a second computer machine 14 , and a communication network 16 . A computer machine is either a physical machine (e.g., a computer) or a virtual machine that runs on one or more computers. Each computer includes a processor (such as a CPU or a microprocessor), memory (RAM, ROM, etc.), and I/O elements, and one or more peripherals (e.g., display, keyboard, mouse, etc.). The second computer machine 16 includes, among other components, an unsupervised behavior learning (“UBL”) system 18 .
[0026] In some implementations, the UBL system 18 is a virtual module that runs on a distributed computing infrastructure such as the Xen platform. The UBL system 18 is scalable and can induce behavior models for a large number of application components on-the-fly without imposing excessive learning overhead. Production distributed infrastructures typically have less than 100% resource utilization. The UBL system 18 utilizes these residual resources to perform behavior learning as background tasks that are co-located with different application VMs (e.g., foreground tasks) on distributed hosts.
[0027] FIG. 2 illustrates an exemplary process 20 of operating the UBL system 18 to predict performance anomalies in the first computer device 12 . The steps of the process 20 are described in an iterative manner for descriptive purposes. Various steps described herein with respect to the process 20 are capable of being executed simultaneously, in parallel, or in an order that differs from the illustrated serial and iterative manner of execution. The process 20 includes, among other steps, a behavior learning phase (step 22 ), a performance anomaly prediction phase (step 24 ), and a performance anomaly cause inference phase (step 26 ).
[0028] In the behavior learning phase (step 22 ), the UBL system 18 determines a model that represents normal system behavior of a VM (e.g., the first computer machine 12 ). In some implementations, the model is a SOM. The SOM maps a high dimensional input space into a low dimensional map space while preserving the topological properties of the original input space (i.e., two similar samples will be projected to close positions in the map). The UBL system 18 can dynamically induce a SOM for each VM of the virtualized distributed computing infrastructure 10 to capture the different VM behaviors. The SOM is composed of a set of nodes. The nodes are referred to as “neurons.” The neurons are arranged in a lattice formation. In some implementations, the neurons are arranged in a gird formation. Each neuron is associated with a weight vector W(t) and a coordinate in the SOM. The SOM is developed based on a plurality of measurement vectors D(t)=[x 1 , x 2 , . . . , x n ] included in a set of unlabeled training data, where x i denotes one system-level metric (e.g., CPU, memory, disk I/O, or network traffic) of a VM at time instance t. The weight vectors are the same length as the measurement vectors (i.e., D(t)).
[0029] FIG. 3 illustrates an exemplary process 30 for operating the UBL system 18 to perform the behavior learning phase 22 . The UBL system 18 receives a set of unlabeled training data (step 31 ). The set of unlabeled training data includes a plurality of measurements vectors. The UBL system 18 updates the SOM for each measurement vector in the plurality of measurement vectors (step 32 ). Next, the UBL system 18 calculates a neighborhood area size for each neuron in the SOM (step 33 ). The UBL system 18 calculates a neuron's neighborhood area size by examining each neuron's immediate neighbors. In the two-dimensional lattice topography, immediate neighbors include the top, left, right, and bottom neighbors. In some implementations, the UBL system 18 calculates the Manhattan distance between the neuron and its neighbor. The Manhattan distance between two neurons N i , N j , with weight vectors W i =[w 1,i , . . . , w k,i ], W j =[w 1,j , . . . , w k,j ] respectfully, is:
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[0030] The neighborhood area size for neuron is the sum of the Manhattan distance between the neuron N i and its top, left, right, and bottom immediate neighbors denoted by N T , N L , N R , and N B :
[0000]
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[0031] Next, the UBL system 18 sorts all of the calculated neighborhood area size values (step 34 ) and sets a threshold value to be the neighbor area size value at a predetermined percentile (step 35 ). In some implementations, the predetermined percentile value is 85%. Other percentile values are used in different implementations.
[0032] FIG. 4 illustrates an exemplary process 40 for operating the UBL system 18 to update the SOM based on a measurement vector from a set of unlabeled training data. The UBL system 18 receives an input measurement vector from the set of unlabeled training data (step 42 ). The UBL system 18 compares a Euclidean distance of the input measurement vector to each different neuron's weight vector in the SOM (step 44 ). Next, the UBL system 18 selects the neuron with the smallest Euclidean distance as the currently trained neuron (step 46 ). Then, the UBL system 18 updates the weight vectors of the currently trained neuron and the neurons that are in the neighborhood of the currently trained neuron (step 48 ). In some implementations, any neuron that is in a radius of r units from the currently trained neuron is considered to be inside the neighborhood. An exemplary formula, used by the method, for updating the weight vector of any neuron at time t is:
[0000] W ( t+ 1)= W ( t )+ N ( v,t )· L ( t 0 ·( D ( t )− W ( t ))
[0033] N(v,t) is a neighborhood function (e.g., a Gaussian function) which depends on the lattice distance to a neighbor neuron v. L (t) is a learning coefficient that can be applied to modify how much each weight vector is changed in different iterations of the behavior learning phase.
[0034] FIG. 5 illustrates an exemplary iteration of process 40 . In this exemplary iteration, the SOM includes 9 neurons. The weight vectors for each neuron in SOM 52 represent the values before the SOM is updated with an input measurement vector 54 . In this exemplary iteration, the input measurement vector 54 is [0, 2, 4]. The weight vectors in SOM 56 represent the values after the SOM is updated with the input measurement vector 54 . The UBL system 18 selects neuron 1 as the currently trained neuron because it has the smallest Euclidean distance to the input measurement vector 54 . The UBL system 18 updates the weight vector of neuron 1. In this exemplary iteration: r=1, L=1, and N=1/4. Accordingly, the UBL system 18 updates the weight vectors of neurons 2, 4, and 5 as they are in the neighborhood of neuron 1. The neighborhood function used in this exemplary iteration is simple and only intended to help illustrate the process. It is to be understood that more complex neighborhood functions are used in other implementations of the invention.
[0035] FIG. 6 illustrates an exemplary process 60 for operating the UBL system 18 to perform the performance anomaly prediction phase 24 . The UBL system 18 receives a real-time input measurement vector (step 61 ). The UBL system 18 maps the real-time input measurement vector to a neuron in the SOM (step 62 ). In some implementations, the UBL system 18 performs mapping with the same Euclidean distance metric used in the behavior learning phase 22 . Next, the UBL system 18 compares the neighborhood area size value (i.e., S(N i )) of the neuron that the real-time input measurement vector is mapped to with the set threshold (step 63 ). The UBL system 18 classifies the real-time input measurement vector as normal, if it is mapped to a neuron with a neighborhood area size value that is below the threshold (step 64 ). On the other hand, the UBL system 18 classifies a real-time input measurement vector as anomalous, if it is mapped to a neuron with a neighborhood area size that is greater than or equal to the threshold (step 65 ). The UBL system 18 determines if a threshold number of consecutive anomalous real-time input measurement vectors have occurred (step 66 ). If a threshold number of consecutive anomalous real-time measurement vectors have occurred, the UBL system 18 outputs an alarm (step 67 ). In some implementations, the UBL system 18 output the alarm if three consecutive anomalous real-time measurement vectors have occurred. In other implementations, the UBL system 18 uses a threshold number other than three.
[0036] Performance anomalies, such as long service level objective (“SLO”) time violations, in distributed infrastructures often manifest as anomalous changes in system-level metrics. Faults do not always cause an instantaneous SLO failure. Instead there is a time window from when the faults occur to the actual time of failure. Therefore, at any given time, the first computer machine 12 can be thought to be operating in one of three states: normal, pre-failure, and failure. FIG. 7 illustrates an exemplary system failure where the UBL system 18 follows a path through SOM 70 over time. The first computer machine 12 typically enters the pre-failure state before entering the failure state. Neurons 1-8 in SOM 70 represent normal state neurons. Neurons 9-13 in SOM 70 represent pre-failure state neurons. Neurons 14-16 in SOM 70 represent failure state neurons. The arrows in SOM 70 represent the evolving path of the UBL system 18 .
[0037] FIGS. 8 and 9 illustrate two example SOM models after the behavior learning phase. FIG. 8 illustrates a SOM model for a RUBiS web server with a network hog bug. RUBiS is an online auction benchmark. FIG. 9 illustrates a SOM model for an IBM System S with a memory leak bug. IBM System S is a commercial stream processing system. In FIGS. 8 and 9 , the X axis and Y axis represent the coordinates of the neurons and the gray-scale visualization identifies behavior patterns. Darker neurons represent anomalous behavior while lighter neurons represent normal behaviors.
[0038] Upon deciding to raise an alarm, the UBL system 18 enters the performance anomaly cause inference phase 26 . In this phase, the UBL system 18 determines and outputs the system-level metrics that differ the most as faulty metrics. FIG. 10 illustrates an exemplary process 100 for operating the UBL system 18 to perform the performance anomaly cause inference phase 26 . The UBL system 18 determines a set of normal neurons that are nearby to the anomalous neuron which the last real-time input measurement vector was mapped to (step 102 ). In some implementations, if a neighbor neuron has a neighborhood area value that is above the threshold, the UBL system 18 ignores it and moves on to the next neuron in the neighborhood. If no normal neuron is found in the anomalous neuron's neighborhood, the UBL system 18 expands the distance calculation to include more neurons in the SOM.
[0039] Next, the UBL system 18 determines a set of metric ranking lists (step 104 ) by calculating the differences between the individual metric values of each normal neuron in the set and the individual metric values of the anomalous neuron. For each metric ranking list in the set, the UBL system 18 determines the absolute value of the calculated difference and sorts the metric differences from the highest to the lowest in order to determine a ranking order.
[0040] Then, the UBL system 18 determines a final ranking order for each of the rankings (step 106 ). In some implementations, the final ranking order is determined using majority voting. The UBL system 18 ascertains a first ranked metric by comparing the top ranked metric from each ranking list. The metric that is in the most ranking lists as the top ranked metric is set as the first ranked metric. The UBL system 18 repeats the above process to determine the final ranking of all of the other metrics. In the case of a tie, the UBL system 18 selects the metric that happens to be placed first in the final ranking list construction.
[0041] After determining a final ranking list for the metrics of the anomalous neuron, the UBL system 18 raises an alarm that contains the final ranking list of metrics (step 108 ).
[0042] In some implementations, the UBL system 18 performs retraining in the performance anomaly prediction phase 26 . In some implementations, retraining includes updating the weight vectors of the SOM with real-time input measurement vectors, similar to processes used in the behavior learning phase 22 . In some implementations, retraining also includes recalculating the neighborhood area size for each neuron in the SOM using the updated weight vectors. In some implementations, retraining occurs for each real-time input measurement vector after it has been mapped to a neuron and identified as normal or anomalous. In some implementations, retraining occurs for a plurality of real-time input measurement vectors after the plurality of real-time input measurement vectors have all been mapped to a neuron and identified as normal or anomalous. In some implementations, retraining occurs if a plurality of system failures occur and the method did not predict them. In some implementations, retraining occurs if the method predicts a large number of anomalies within a predetermined time frame.
[0043] If is to be understood that the unsupervised behavior learning, performance anomaly prediction, and performance anomaly cause inference methods described above can also be implemented on a distributed computing infrastructure that runs application PMs.
[0044] Thus, the invention provides, among other things, mechanisms for assessing the performance of a computing system. Various features and advantages of the invention are set forth in the following claims. | An unsupervised behavior learning system and method for predicting anomalies in a distributed computing infrastructure. The distributed computing infrastructure includes a plurality of computer machines. The system includes a first computer machine and a second computer machine. The second computer machine is configured to generate a model of normal and anomalous behavior of the first computer machine, where the model is based on unlabeled training data. The second computer machine is also configured to acquire real-time data of system level metrics of the first machine; determine whether the real-time data is normal or anomalous based on a comparison of the real-time data to the model; and predict a future failure of the first computer machine based on multiple consecutive comparisons of the real-time data to the model. Upon predicting a future failure of the first computer machine, generate a ranked set of system-level metrics which are contributors to the predicted failure of the first computer machine, and generate an alarm that includes the ranked set of system-level metrics. The model of normal and anomalous behavior may include a self-organizing map. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 12/203,415, filed Sep. 3, 2008, which claims priority to U.S. Provisional Application Ser. No. 60/982,128, filed Oct. 23, 2007, the contents of which are incorporated herein by reference in their entireties.
FIELD OF THE INVENTION
[0002] Various embodiments of the present invention relate generally to methods and systems for encryption and tokenization architectures for sensitive data such as credit card number.
BACKGROUND OF THE INVENTION
[0003] In today's world of information storage, there are many circumstances wherein information must be securely stored and used. For example, many merchants and service providers accept credit cards for the payment of goods and services they sell. In order to accept a credit card for payment, a merchant or service provider will record a purchaser's credit card number along with other information, and submit the number and information for payment to the issuer of the credit card, such as Visa. In many cases this information is encrypted due to the sensitivity of the information and the threat of a third-party illegally obtaining the information, e.g., a hacker breaking into a merchant's computer system and illegally copying this information.
[0004] In addition, major credit card companies have developed guidelines to help merchant and service providers prevent credit card fraud, hacking, and various other security issues. These guidelines are known as the Payment Card Industry Data Security Standard (PCI DSS). Therefore, any merchant or service provider processing, storing, or transmitting credit card numbers must adhere to these standards or risk losing the ability to process credit card payments. These guidelines involve twelve requirements for compliance. For example, the guidelines require that any cardholder data stored must be protected. In addition, any transmission of cardholder data across open, public networks must be encrypted.
[0005] Encryption can be a complex process that involves encrypting and decrypting the cardholder data through the use of tools such as asymmetric-keys. For example, in public-key cryptography the encryption process involves using two keys, i.e., a public-key and a private key. The public key may be freely distributed, while its paired private key is kept secret. Typically, the public key is used for encrypting the data while the private key is used for decrypting the data. Therefore, these keys must be maintained and securely stored. Thus, every time a merchant or service provider transmits cardholder data, they must perform this encryption and decryption process. This can lead to inefficient processing of credit card payments.
[0006] As a result, a need exists in the art to better utilize sensitive information, yet minimize the transferring of such information. Such an improvement will also lead to better efficiency because the need for encrypting and decrypting will be reduced to use such information.
BRIEF SUMMARY OF THE INVENTION
[0007] Various embodiments of the present invention are directed to systems and methods for transmitting a character string. In addition, various embodiments are directed to systems and methods for transmitting a unique token associated with a character string.
[0008] In particular, various embodiments provide a method of transmitting a character string comprising the step of adapting one or more processors for executing a gatekeeper module. The gatekeeper module in these embodiments is adapted for: (a) storing the character string in one or more storage devices; (b) associating a unique token with the character string; and (c) associating a sub-string of the character string with the unique token to identify that the unique token is associated with the character string without revealing the character string. In addition, in response to receiving a request for the character string, the gatekeeper module is further adapted for accessing the character string from the one or more storage devices by using the unique token associated with the character string and transmitting the character string.
[0009] In various embodiments, the gatekeeper module is further adapted for verifying that a computer device or a user making the request for the character string is authorized to receive the character string. In addition, in various embodiments, the character string is stored as encrypted data and/or stored as a record in a database. Furthermore, in various embodiments, the character string is a credit card number and the associated sub-string used to identify the credit card number is the last four digits of the credit card number.
[0010] As another example, various embodiments of the present invention provide a method for transmitting a unique token associated with a character string comprising the step of adapting one or more processors for executing a gatekeeper module. In these embodiments, the gatekeeper module is adapted for: (a) storing the character string in one or more storage devices; (b) associating the unique token with the character string; and (c) associating a sub-string of the character string with the unique token to identify that the unique token is associated with the character string without revealing the character string. In addition, in response to receiving a request for the unique token associated with the character string, the gatekeeper module is further adapted for accessing the unique token from the one or more storage devices using the character string and transmitting the unique token associated with the character string. In various embodiments, the gatekeeper module is also adapted for verifying that a computer device or a user making the request for the unique token is authorized to receive the unique token.
[0011] Furthermore, various embodiments provide a system for transmitting a character string comprising one or more processors and one or more storage devices coupled to the processors and adapted for storing the character string. The processors of these particular embodiments are adapted to execute a gatekeeper module to (a) store the character string within the storage devices; (b) associate a unique token with the character string; and (c) associate a sub-string of the character string with the unique token to identify that the unique token is associated with the character string without revealing the character string. In addition, in response to receiving a request for the character string, the processors are further adapted to execute the gatekeeper module to access the character string from the storage devices by using the unique token associated with the character string and transmit the character string.
[0012] In various embodiments, the processors are also adapted to execute the gatekeeper module to verify that a computer device or a user making the request for the character string is authorized to receive the character string. In addition, in various embodiments, the character string is stored as encrypted data and/or stored as a record in a database within the storage devices.
[0013] Other embodiments provide a system for transmitting a unique token associated with a character string comprising one or more processors and one or more storage devices coupled to the processors and adapted for storing the character string. The processors of these particular embodiments are adapted to execute a gatekeeper module to: (a) store the character string within the storage devices; (b) associate a unique token with the character string; and (c) associate a sub-string of the character string with the unique token to identify that the unique token is associated with the character string without revealing the character string. In addition, in response to receiving a request for the unique token, the processors are further adapted to execute the gatekeeper module to access the unique token from the storage devices by using the character string associated with the unique token and transmit the unique token. In various embodiments, the processors are also adapted to execute the gatekeeper module to verify that a computer device or a user making the request for the unique token is authorized to receive the unique token.
[0014] In various embodiments, a method for conducting an online transaction on a website involving sensitive information is provided. In such embodiments, the method comprises: (a) registering at least one entity with a gate keeper module, the registering comprising associating the at least one entity with a subscription level; (b) associating a sub-string of a character string with a unique token so that a direct link does not exist between the unique token and the character string, the character string comprising the sensitive information and the sub-string being configured to identify the character string without revealing the sensitive information; and (c) during processing of the online transaction: (i) using the unique token for intermediate steps during the processing of the online transaction; and (ii) only accessing the character string in storage memory using the unique token and the sub-string to retrieve the sensitive information and to complete the online transaction using the information for the online transaction and the sensitive information after receiving a request for the sensitive information from at least one of the at least one registered entity associated with a subscription level associated with a privilege to receive the requested sensitive information.
[0015] In various embodiments, a system for conducting an online transaction on a website involving sensitive information is provided. In such embodiments, the system comprises one or more processors; and one or more storage devices coupled to the one or more processors and adapted for storing a character string. The one or more processors may execute a gatekeeper module to: (a) register at least one entity with the gatekeeper module, the registering comprising associating the at least one entity with a subscription level; (b) associate a unique token with a sub-string of a character string wherein a direct link does not exist between the unique token and the character string, the character string comprising the sensitive information and the sub-string being configured to identify the character string without revealing the sensitive information; and (c) during processing of the online transaction: (i) use the unique token for intermediate steps during the processing of the online transaction; and (ii) only access the character string in the one or more storage devices using the unique token and the sub-string-to retrieve the sensitive information and to complete the online transaction using the information for the online transaction and the sensitive information after receiving a request for the sensitive information from at least one of the at least one registered entity associated with a subscription level associated with a privilege to receive the requested sensitive information.
[0016] In yet other embodiments, a computer program product for conducting an online transaction on a website involving sensitive information, wherein the computer program product comprises at least one non-transitory computer-readable storage medium having computer-readable program code portions stored therein, is provided. In such embodiments, the computer-readable program code portions may comprise: (a) an executable portion configured to register at least one entity with the gatekeeper module, the registering comprising associating the at least one entity with a subscription level; (b) an executable portion configured to associate a unique token with a sub-string of a character string wherein a direct link does not exist between the unique token and the character string, the character string comprising the sensitive information and the sub-string being configured to identify the character string without revealing the sensitive information; and (c) during processing of the online transaction: (i) an executable portion configured to use the unique token for intermediate steps during the processing of the online transaction; and (ii) an executable portion configured to only access the character string in one or more storage devices using the unique token and the sub-string-to retrieve the sensitive information and to complete the online transaction using the information for the online transaction and the sensitive information after receiving a request for the sensitive information from at least one of the at least one registered entity associated with a subscription level associated with a privilege to receive the requested sensitive information.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0017] Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:
[0018] FIG. 1 is a flowchart illustrating a process for transmitting a character string according to various embodiments of the invention.
[0019] FIG. 2 is a flowchart illustrating a process for transmitting a unique token associated with a character string according to various embodiments of the invention.
[0020] FIG. 3 is a schematic diagram illustrating a system architecture including a gatekeeper system according to various embodiments of the invention.
[0021] FIG. 4 is a schematic diagram illustrating a system storing a gatekeeper module according to various embodiments of the invention.
[0022] FIG. 5 is a flow diagram of a gatekeeper module transmitting a character string according various embodiments of the invention.
[0023] FIG. 6 is a flow diagram of a gatekeeper module transmitting a unique token associated with a character string according to various embodiments of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0024] The present invention will now be described more fully with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. Indeed, this invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.
[0025] As will be appreciated by one skilled in the art, the present invention may be embodied as a method, a data processing system, or a computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product on a computer-readable storage medium having computer-readable program instructions (e.g., computer software) embodied in the storage medium. More particularly, the present invention may take the form of web-implemented computer software. Any suitable computer-readable storage medium may be utilized including hard disks, CD-ROMs, DVD-ROMs, USB flash drives, optical storage devices, or magnetic storage devices.
[0026] The present invention is described below with reference to block diagrams and flowchart illustrations of methods, apparatuses (i.e., systems) and computer program products according to an embodiment of the invention. It will be understood that each block of the block diagrams and flowchart illustrations, and combinations of blocks in the block diagrams and flowchart illustrations, respectively, can be implemented by computer program instructions. These computer program instructions may be loaded onto a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions which execute on the computer or other programmable data processing apparatus create a means for implementing the functions specified in the flowchart block or blocks.
[0027] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including computer-readable instructions for implementing the function specified in the flowchart block or blocks. The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions that execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks.
[0028] Accordingly, blocks of the block diagrams and flowchart illustrations support combinations of means for performing the specified functions, combinations of steps for performing the specified functions and program instruction means for performing the specified functions. It will also be understood that each block of the block diagrams and flowchart illustrations, and combinations of blocks in the block diagrams and flowchart illustrations, can be implemented by special purpose hardware-based computer systems that perform the specified functions or steps, or combinations of special purpose hardware and computer instructions.
Transmitting a Character String
[0029] Various embodiments of the present invention provide systems and methods for transmitting a character string. Such embodiments include providing a gatekeeper module that is executed on a computer to: (1) store a character string within one or more storage devices; (2) associate a unique token with the character string; (3) associate a sub-string of the character string with the unique token to identify that the unique token is associated with the character string without revealing the character string; and (4) in response to receiving a request for the character string, access the character string from the one or more storage devices by using the unique token associated with the character string, and transmit the character string to a computer device or a user requesting the string.
[0030] FIG. 1 is an exemplary process for transmitting a character string 100 according to various embodiments of the invention. The process comprises the step of adapting one or more processors (“processor”) for executing a gatekeeper module, shown as Step 101 . These processors may be located in one or more computer systems and may be in communication via a network (e.g., a LAN network, wireless network, or the Internet).
[0031] Thus, the processor executes the gatekeeper module of various embodiments to store the character string in one or more storage devices. For example, the processor may execute the gatekeeper module to store the character string in a database located on the storage devices. The processor may execute the gatekeeper module in other embodiments to store the character string in a file located on a storage device. Furthermore, the processor may execute the gatekeeper module to store the character string in other embodiments in a data warehouse, or some type of program module located on storage devices.
[0032] In addition, various types of storage devices may be used according to various embodiments of the invention. For instance, the storage devices may be internal or external hard drives, storage disks, magnetic tape, USB flash drives, or some other type of storage devices as known by those of ordinary skill in the art.
[0033] In many cases the character string represents sensitive information, and therefore, the processor will execute the gatekeeper module to store the string as encrypted data in various embodiments. For example, the character string may be a customer credit card number that is received by a merchant or service provider from a customer purchasing a product or service by using a credit card. In this context, the merchant or service provider records the credit card number along with other information associated with the credit card and customer so that the credit card information can be submitted to the issuer of the credit card for payment.
[0034] Furthermore, the storing of credit card information has become even more predominate in the advent of online shopping via the Internet. For example, a user will visit a retailer's web site via a browser located on the user's computer, browse the retailer's products, select one or more products for purchase, and in many cases, proceed to a “checkout” webpage provided by the retailer's web site to complete the purchase. Once on the “checkout” webpage, the user provides credit card information by typing in the information on the webpage to pay for the selected products. A server will execute a module associated with the webpage to store the credit card information and complete the purchase. In addition, in many instances a user will visit the retailer's web site multiple times to shop again. As a result, the retailer may retain the user's credit card information in one or more storage devices to help facilitate a quicker checkout for the user for subsequent purchases, e.g., the user's credit card information may be automatically populated on the “checkout” webpage so that the user is not required to re-enter the information for a subsequent purchase.
[0035] Other types of sensitive information may also be stored in the storage devices as encrypted data. For example, many organizations store social security numbers for various reasons and will encrypt the social security numbers for security purposes. However, the credit card example is utilized throughout this document to illustrate the various embodiments of the present invention. Thus, it should be understood that the credit card example is used for illustration purposes only and in no way should limit the specific kind of sensitive data that may be used with the claimed invention.
[0036] Returning to the example, in various embodiments, the processor executes the gatekeeper module to receive a customer's credit card number, encrypt the number, and store the number in a database. In addition to the credit card number, the gatekeeper module may store various other information in the database, such as credit card expiration date, credit card type, status of the credit card (e.g., active), parent system, and profile flag. In various embodiments, the processor may execute the gatekeeper module to use various encryption techniques to encrypt the credit card number and information. For example, the module may employ asymmetric-key encryption to encrypt the credit card number. Asymmetric-key encryption involves the use of keys to encrypt or decrypt the information. A common type of asymmetric-key encryption is known as public-key encryption. This type of encryption involves the use of two different keys, i.e., a public key and a private key. The public key is freely distributed and is typically used for encryption, while the private key is kept secured and is typically used for decryption.
[0037] Lastly, the storage devices used to the store the character strings may be provided as a centralized repository according to various embodiments of the invention. Such a repository may be important in the context of storing sensitive information such as credit card numbers. For example, those managing the repository can implement corrective measures more quickly by having a centralized repository to store the credit card numbers in the case of a security breach. In addition, such a repository centralizes the protection of the sensitive information, and therefore, raises the quality of protection because implementing protective and corrective measures is much simpler for a centralized repository as opposed to many repositories. Thus, a centralized repository reduces the scope of the information that must be protected, reduces security efforts, and reduces the labor and overhead required to protect the information.
[0038] Furthermore, a centralized repository aids in the compliance with Payment Card Industry Data Security Standard (PCI DSS) guidelines used in the context of credit card information. For example, the centralized repository assists in logging compliance with PCI DSS guidelines because such logging deals with only one source of credit card information. In addition, it is easier to restrict access to the repository because it is easier to pre-define and manage a list of entities that may access the repository, as well as, track and monitor those entities that have accessed the repository. It is also easier to restrict physical access to the credit card information because the centralized repository can be housed on one system, e.g., one server or bank of servers, and access to this system can be restricted.
[0039] In various embodiments, the processor also executes the gatekeeper module to associate a unique token with the character string. Returning to the example, the module stores the encrypted credit card number in the database and assigns a unique token to the encrypted credit card number.
[0040] The processor executes the gatekeeper module to create the unique token using various processes. For example, in various embodiments, the module creates the unique token by calling a random number generator module. Such a module typically includes an algorithm that can automatically create long runs, e.g., millions of numbers long, with good random properties. However, in many cases, the sequence created by the algorithm will eventually repeat. Therefore, once the random number generator module has provided a random number, the processor further executes the gatekeeper module to check the provided number against the existing tokens to ensure the acquired random number is unique. If the random number is unique, the processor executes the gatekeeper module to associate the random number with the encrypted credit card number in the database.
[0041] In other embodiments, the processor executes the gatekeeper module to employ database primary keys used to distinguish records in a database table to provide unique tokens. For example, a record stored in the table of a database may be made a unique record with respect to other records stored in the same table by requiring that one or more fields of the record, alone or in combination, store a unique value from the same one or more fields of other records stored in the table. This is referred to as developing primary keys to one of ordinary skill in the art. In addition, many commercial database applications also provide a feature that will allow a field in a database table to be defined so that a unique primary key is automatically generated and written into the field for a new record stored in the table. Thus, in the example, this feature generates a unique primary key to store in a field of a table in the database when the processor executes the gatekeeper module to store the encrypted credit card number in the table. The module will then use the generated primary key as the unique token associated with the credit card number.
[0042] In various embodiments, the processor executes the gatekeeper module to store the unique token in the same storage as the character string. In other embodiments, the processor executes the gatekeeper module to store the unique token in separate storage. Thus, in the example, the processor executes the gatekeeper module to store the unique token in the same database as the encrypted credit card number or in a separate database.
[0043] The decision as to whether to store the unique tokens in the same database as the encrypted credit card numbers or in a separate database may be based on different considerations. For example, the processor may execute the gatekeeper module in various embodiments to store the unique tokens separately from the encrypted information for security reasons. In other instances, the processor may execute the gatekeeper module to store the unique tokens in the same database as the encrypted information to help centralize the information for management purposes. One of ordinary skill in the art can think of various other reasons to store the tokens and the character strings in the same or separate storage devices in light of this disclosure.
[0044] In addition, in various embodiments, the processor executes the gatekeeper module to associate the unique token with a sub-string of the character string associated with the token to identify that the token is associated with the character string without revealing the character string. In various embodiments, the processor executes the gatekeeper module to store this sub-string along with its corresponding token. In other embodiments, the processor executes the gatekeeper module to store the sub-string and token in separate storage. Thus, there is nothing identifiable in the token to link the token to the corresponding character string directly. Instead, the token uses a formal protected cross reference to link to the character string.
[0045] An example of such a sub-string is the last four digits of a credit card number. Therefore, if a user visiting a retailer's web site proceeds to the “checkout” webpage to purchase a product, the user can request to see what credit cards the merchant has on file for the user, e.g., what credit card numbers are stored in the retailer's database. In various embodiments, a server executes a module associated with the web page to query the database and instead of processor returning the actual credit card numbers to the module, the processor executes the gatekeeper module to return the tokens associated with the stored credit card numbers along with the last four digits of each credit card number stored in the database. The server then executes the module to display the last four digits of each credit card on the web site to the user. As a result, the user is able to recognize each stored credit card number and choose the credit card to which he or she wishes to charge the purchase.
[0046] The use of such a sub-string provides a significant advantage over previous processes. This is because to show the user what credit card numbers are stored in the database in previous processes, a module would need to be executed to query the database for the credit card numbers, encrypt the credit card numbers if the numbers were decrypted to be queried from the database, send the numbers to the webpage for displaying, and decrypt the numbers to display them to the user. This complex process is required to be performed in this fashion to ensure the security of the information from such threats as hackers, as well as, to be in compliance with the PCI DSS guidelines.
[0047] However, by having the module display the sub-strings to identify particular credit card numbers instead of the actual credit card numbers on the webpage, the user can view what credit card numbers are stored in the database for him or her without the module having to perform the complex process to access and transmit the actual credit card numbers to the webpage. As a result, the credit card numbers stay encrypted and secured in the database. Thus, encryption and decryption activities are minimized and the flow of sensitive information is reduced.
[0048] Accordingly, in response to the gatekeeper module receiving a request for a character string, the processor executes the gatekeeper module to access the string from storage by using the unique token associated with the character string. Therefore, returning to the example, once the user has selected a particular credit card number to which he or she wishes to charge the purchase from the last four digits displayed on the “checkout” webpage, the module that is executed to facilitate the purchase from the webpage sends a request for the specific credit card number to the gatekeeper module. In response, the processor executes the gatekeeper module to access the actual credit card number by using the unique token associated with the requested credit card number. For example, the processor executes the gatekeeper module to query the actual credit card number from the repository by using the unique token as a search parameter of the query.
[0049] In various embodiments, various computer devices and users may submit the request for the character string, and at various times. For example, once the user selects a particular credit card to which to charge the purchase, a server executes the module to facilitate the purchase to save the purchase to a database. A computer device may later batch this purchase with other purchases and submit the purchases to a credit card company for payment. In this case, the server executes the module to save the unique token for the selected credit card along with the purchase in the database and the device that executes the module to perform the batching is the device that requests the actual credit card number by using the token. This also provides an advantage over previous processes because in a process that involves multiple transactions, a number of computer devices executing the modules involved in the transactions may only need a reference to the credit card number as opposed to the actual credit card number. In this case, these devices will use the token to process transactions unless there is a specific reason the device needs the actual credit card number, such as submitting the purchase information to the credit card company for payment.
[0050] In addition, the processor executes the gatekeeper module of various embodiments to verify whether the device or the user requesting the character string is authorized to receive the character string. Thus, the module provides formal access controls in various embodiments. For example, the gatekeeper module may include an application programming interface (API) to regulate the interaction between independent computer devices and individuals and the database storing the sensitive information according to various embodiments of the invention. Specifically, a computer device or a user that makes a request to access a character string must first register with the gatekeeper module. Therefore, in the case of the credit card example, a mechanism is implemented to control who and what can access the credit card numbers in the database.
[0051] In various embodiments, the device or the user subscribes with the gatekeeper module to gain access to the information stored in the database. As a result, the processor will execute the gatekeeper module to give various devices and users various levels of access. For example, the computer device executing the batching module discussed above that batches up the credit card charges and submits the charges to the credit card company subscribes with the gatekeeper module to be able to request the credit card numbers. Another device that records and reports a user's transaction history may only need to retrieve the sub-strings associated with the tokens to display a user's transaction history, and therefore, this device's subscription only provides access to the sub-strings. In turn, the processor may execute the gatekeeper module to provide other subscription levels, such as privileges to access tokens only, according to various other embodiments.
[0052] Thus, the device or the user will need to provide a token, a sub-string, or some other information and sufficient credentials that allow the device or the user to perform the type of access or manipulation of the information the device or the user wants to perform. In various embodiments, the credentials may take many forms. For example, the processor may execute the gatekeeper module to provide the credentials as a key to the device upon registration with the gatekeeper module. In other embodiments, the processor may execute the gatekeeper module to provide credentials by simply checking the name of the device or the user against a record in a database table to determine whether the device or the user has privilege to perform the request. One of ordinary skill in the art can think of numerous ways for the processor to execute the gatekeeper module to provide and check credentials for a device or a user to establish the device's or the user's level of access to the information in light of this disclosure.
[0053] In addition, the processor can execute the gatekeeper module to monitor the retention of the character strings and associated information stored in the storage devices in various embodiments. Therefore, the processor can execute the gatekeeper module to determine whether any of the sensitive information stored is out-dated and should be deleted or archived from the database. As a result, this will minimize the amount of sensitive information stored in the storage devices and also minimize the liability of storing such information.
[0054] Thus, returning to the example wherein the database is storing the credit card numbers of users who have visited a retailer's web site to purchase goods from the retailer, the processor executes the gatekeeper module to periodically check to determine whether any of the credit card numbers have expired or whether any of the credit card numbers have not been used within a set period of time, e.g., whether a certain period of time has elapsed since the credit card number was last used to make a purchase. Therefore, if a credit card number has expired or has not been used within the set period of time, the processor executes the gatekeeper module to delete the credit card number along with any corresponding information from the database. In various embodiments, the processor may first execute the gatekeeper module to archive the credit card number and corresponding information to an external storage medium, such as a disk or tap drive, before deleting the information.
[0055] The processor can execute the gatekeeper module to monitor the character strings through various techniques. In one embodiment, the gatekeeper module may have a scheduling feature executed by the processor to check each record in the database at a certain time each day to determine if any credit card numbers need to be purged from the database. For example, the processor executes the scheduling feature every morning at three o'clock a.m. and filters out any records that need to be purged from the database. In another embodiment, the processor simply executes the gatekeeper module to check each credit card number stored for a user in response to the module receiving a request for a credit card number associated with the user to determine if any of the user's stored credit card numbers are out of date. One of ordinary skill in the art can envision several techniques that may be employed to ensure the out-dated character strings and corresponding information are purged in light of this disclosure.
[0056] Finally, processor executes the gatekeeper module to transmit the character string to the device or the user requesting the string according to various embodiments of the invention. It should be understood that the term “transmit” does not necessarily mean the gatekeeper module sends the character string to the device or the user. For example, in various embodiments, the processor executes the gatekeeper module to grant the device or the user permission to access the character string in storage. Thus, the term “transmit” is used in this disclosure to mean that the processor executes the gatekeeper module to facilitate the device or the user obtaining the character string.
[0057] As previously discussed, the device or the user making the request can vary by embodiment. For example, the device may be a server executing a program module, a Graphical User Interface (GUI), or an external source such as a credit card company computer system. In addition, the processor may execute the gatekeeper module to transmit the character string in various forms. For example, processor may execute the gatekeeper module to return the character string in a digital format such as in a data stream, a file, or an e-mail or to display the character string on a computer monitor. The processor may also execute the gatekeeper module to encrypt or decrypt the character string, or simply return the string as standard text. One of ordinary skill in the art is familiar with the numerous ways the character string can be returned from the storage devices and stored or displayed in light of this disclosure.
[0000] Transmitting a Unique Token Associated with a Character String
[0058] In many instances, a device or a user may need to access a unique token associated with a character string. For instance, a user may visit a retailer's web site and select a product to purchase. The module executed to facilitate the purchase on the web site forwards the user to a “checkout” webpage and instead of choosing an existing credit card number stored in the retailer's database, the user enters a new credit card number and completes the purchase. A server executes the module to record the purchase transaction in a database so that the purchase may be later submitted to the credit card company for payment. However, in this case, the module is provided with the credit card number as opposed to a unique token associated with the credit card number. Therefore, the server executes the module to obtain a unique token for the credit card number prior to storing the purchase transaction in the database.
[0059] Accordingly, various embodiments of the present invention are directed to systems and methods for transmitting a unique token associated with a character string. Such embodiments include providing a gatekeeper module that is executed on a computer to: (1) store the character string within one or more storage devices; (2) associate a unique token with the character string; (3) associate a sub-string of the character string with the unique token to identify that the unique token is associated with the character string without revealing the character string; and (4) in response to receiving a request for the unique token associated with the character string, access the unique token from the one or more storage devices by using the character string, and transmit the unique token to a computer device or a user requesting the unique token.
[0060] As displayed in FIG. 2 , an exemplary process for transmitting a unique token associated with a character string 200 according to various embodiments of the invention includes the step of adapting one or more processors (“processor”) for executing a gatekeeper module, shown as Step 201 . These processors may be located in one or more computer systems and may be in communication via a network (e.g., a LAN network, a wireless network, or the Internet).
[0061] The processor executes the gatekeeper module of various embodiments to store the character string in one or more storage devices, as shown in Step 201 . The processor executes the gatekeeper module to perform this step in the same manner as in the process for transmitting a character string 100 . For example, the processor executes the gatekeeper module to store the character string in a database, file, data warehouse, or some type of program module according to various embodiments of the invention. In addition, in various embodiments, the character string may represent sensitive information, and therefore, the processor executes the gatekeeper module to store the string as encrypted data. Lastly, the processor may execute the gatekeeper module to store the character string in a central repository according to various embodiments of the invention.
[0062] The processor further executes the gatekeeper module to associate a unique token with the character string according to various embodiments. The processor executes the gatekeeper module to carry out this step in a similar manner to the process for transmitting a character string 100 discussed above. Thus, the processor executes the gatekeeper module to generate a unique token through various processes such as executing a random number generator module or utilizing the primary key associated with a record stored in a database for the character string.
[0063] In addition, in various embodiments, the processor executes the gatekeeper module to associate the unique token with a sub-string of the character string associated with the token in order to identify that the token is associated with the character string without revealing the character string in a manner similar to the process for transmitting a character string 100 . An example of such a sub-string is the last four digits of a credit card number.
[0064] In various embodiments, the processor also executes the gatekeeper module to access a unique token from storage by using the character string associated with the unique token in response to receiving a request for the unique token according to various embodiments. Returning to the example, once the user has entered the credit card information on the “checkout” webpage and completed the transaction, the processor executes the gatekeeper module to encrypt and save the credit card number and related information to the database. In addition, the processor executes the gatekeeper module to generate and associate a unique token with the character string. In conjunction, a batching module is executed to send a request for the unique token associated the specific credit card number and the processor executes the gatekeeper module to access the token via the credit card number. The processor executes the gatekeeper module to return the unique token associated with the credit card number to the batching module and the batching module is executed to save the purchase transaction in a database along with the token as opposed to the new credit card number.
[0065] As in the case of the process for transmitting a character string 100 , the processor also executes the gatekeeper module of process 200 to verify whether the computer device or the user requesting the unique token is authorized to receive the token according to various embodiments of the invention. Thus, the processor executes the gatekeeper module to provide formal access controls in various embodiments to verify that the device or the user making the request has privilege to retrieve the unique token. These formal access controls are similar to the controls discussed above in regard to the process for transmitting a character string 100 .
[0066] Furthermore, in various embodiments, the processor executes the gatekeeper module to transmit the unique token to the device or the user requesting the token. Again, it should be understood that the term “transmit” does not necessarily mean the processor executes the gatekeeper module to send the token to the entity. For example, in various embodiments, the processor may execute the gatekeeper module to grant the device or the user permission to access the token in storage. Thus, the term “transmit” is used in this disclosure to mean that the gatekeeper module facilitates the device or the user obtaining the token.
[0067] As previously discussed, the device making the request can vary by embodiment. For example, the device may be a server executing a program module, a GUI, or an external source such as a credit card company computer system. In addition, the processor may execute the gatekeeper module to transmit the token in various forms. For example, the processor may execute the gatekeeper module to simply return the token in a digital format such as in a data stream, a file, or an e-mail or to display the token on a computer monitor. One of ordinary skill in the art is familiar with the numerous ways information can be returned from the storage devices and stored or displayed in light of this disclosure.
System Architecture
[0068] System 3 includes a gatekeeper system 300 according to various embodiments of the invention is shown as FIG. 3 . As may be understood from this figure, in various embodiments, the system includes in addition to the gatekeeper system 300 , a database server 105 , and one or more application servers 100 - 103 that are connected via a network 104 (e.g., a LAN, a wireless network, the Internet, and/or a private network) to communicate with one another. In one embodiment of the invention, the gatekeeper system 300 is configured for retrieving data from, and storing data to, a database located on the database server 105 (or, alternatively, located on the gatekeeper system 300 ). In alternative embodiments, the system 3 may include more than one database. In other embodiments, the gatekeeper system 300 may be one or more computers or software programs running on one or more computers.
[0069] FIG. 4 shows a schematic diagram of a gatekeeper system 300 storing the gatekeeper module 400 according to one embodiment of the invention. The system 300 includes a processor 60 that communicates with other elements within the server via a system interface or bus 61 . Also included in the system 300 is a display device/input device 64 for receiving and displaying data. This display device/input device 64 may be, for example, a keyboard or pointing device that is used in combination with a monitor. The system 300 further includes memory, which includes both read only memory (ROM) 65 and random access memory (RAM) 67 . The system's ROM 65 is used to store a basic input/output system 26 (BIOS), containing the basic routines that help to transfer information between elements within the system 300 . Alternatively, the system 300 can operate on one computer or on multiple computers that are networked together.
[0070] In addition, the system 300 includes at least one storage device 63 , such as a hard disk drive, a floppy disk drive, a CD ROM drive, a DVD ROM drive, a USB flash drive, or optical disk drive, for storing information on various computer-readable media, such as a hard disk, a removable magnetic disk, a CD-ROM disk, or a DVD-ROM disk. As will be appreciated by one of ordinary skill in the art, each of these storage devices 63 is connected to the system bus 61 by an appropriate interface. The storage devices 63 and their associated computer-readable media provide nonvolatile storage for a personal computer. It is important to note that the computer-readable media described above could be replaced by any other type of computer-readable media known in the art. Such media include, for example, magnetic cassettes, flash memory cards, memory sticks, digital video disks, and Bernoulli cartridges.
[0071] A number of program modules may be stored by the various storage devices and within RAM 67 . For example, as shown in FIG. 4 , program modules of the system 300 include an operating system 80 and a gatekeeper module 400 . The gatekeeper module 400 controls certain aspects of the operation of the system 300 , as is described in more detail below, with the assistance of the processor 60 and an operating system 80 .
[0072] Also located within the system 300 is a network interface 74 , for interfacing and communicating via a network 104 (e.g., a LAN, a wireless network, the Internet, or a private network) with other elements of a computer network, such as application servers 100 - 103 and a database server 105 as shown in FIG. 3 . It will be appreciated by one of ordinary skill in the art that one or more of the system's components 300 may be located geographically remotely from other system components. Furthermore, one or more of the components may be combined, and additional components performing functions described herein may be included in the system 300 .
Exemplary System Operation
[0073] As mentioned above, the system 3 according to various embodiments enables communication between the gatekeeper system 300 , the application servers 100 - 103 , and the database server 105 . In particular, in various embodiments, the gatekeeper system 300 includes a gatekeeper module 400 . The gatekeeper module 400 may be configured to communicate information between one or more application servers 100 - 103 and a database server 105 . This module 400 is discussed in more detail below.
Gatekeeper Module
[0074] FIG. 5 illustrates a flow diagram related to a gatekeeper module 400 transmitting a character string according to various embodiments of the invention. This flow diagram may correspond to the steps carried out by a processor 60 in the system 300 shown in FIG. 4 as it executes the gatekeeper module 300 in the RAM memory 67 of the system 300 .
[0075] In various embodiments, the processor 60 executes the gatekeeper module 400 to initially obtain a character string from an entity such as a computer device or a user. However, it should be understood that the gatekeeper module 300 is not the only component that may be executed to receive the character string to store the string in one or more storage devices. For example, when the “checkout” webpage previously discussed receives a new credit card number from a user, the webpage may call a dedicated module that is executed besides the gatekeeper module 400 to save the credit card number to the database. One of ordinary skill in the art can envision numerous ways to set up a system to save new character strings to the database in light of this disclosure.
[0076] In addition, the entity from which the character string is obtained may be a GUI, a program module running on a computer system, or other component such as a third-party computer system according to various embodiments of the invention. The term “obtain” is used to mean receive or access. This can be accomplished either locally or remotely and may be via a communications network (e.g., a LAN, a wireless network, the Internet, or a private network).
[0077] Accordingly, the processor 60 executes the gatekeeper module 400 to store the character string in storage if the module 400 does receive the character string, shown as Step 502 . In various embodiments, the processor 60 executes the gatekeeper module 400 to store the character string in a database. However, it should be understood by those of ordinary skill in the art that the gatekeeper module 400 does not necessarily need to store the character string in a database. For example, in various embodiments, the processor 60 may execute the gatekeeper module 400 to store the character string in a file, data warehouse, or some type of program module.
[0078] In addition, various types of storage devices may be used according to various embodiments of the invention. For instance, the storage devices may be internal or external hard drives, storage disks, magnetic tapes, USB flash drives, or some other type of storage device as known by those of ordinary skill in the art.
[0079] In many cases the character string represents sensitive information, and therefore, the processor 60 executes the gatekeeper module 400 to encrypt the character string (shown as Step 501 ) and to store the string as encrypted data according to various embodiments. For example, the character string may be a customer credit card number that is received by a merchant or service provider from a customer purchasing a product or service using a credit card.
[0080] In various embodiments, the processor 60 executes the gatekeeper module 400 to perform the encryption process or executes a different module to perform the encryption of the information if the information does need to be encrypted. Thus, the gatekeeper module 400 or other module may employ various techniques to encrypt the credit card number and information, such as asymmetric-key encryption.
[0081] In addition, the processor 60 executes the gatekeeper module 300 of various embodiments to obtain additional information to store in the database that is related to the credit card number. Such information may include credit card expiration date, credit card type, status of the credit card (e.g., active), parent system, and profile flag.
[0082] Lastly, the processor 60 may execute the gatekeeper module 400 to store the character string in a centralized repository according to various embodiments of the invention. Such a repository may be important in the context of storing sensitive information such as credit card numbers, as previously discussed. For example, the processor 60 can execute the gatekeeper module 400 or other computer modules to take corrective measures more quickly in the case of a security breach because the processor only needs to implement the measures on a centralized repository. In addition, the processor 60 can execute the gatekeeper module 400 or other computer modules to implement protective and corrective measures more easily since the character strings and corresponding information are stored in a centralized repository. As a result, the quality of protection is raised.
[0083] In various embodiments, the processor 60 executes the gatekeeper module 400 to associate a unique token to the character string in addition to storing the character string in the database, shown as Step 503 . Thus returning to the example, the processor 60 executes the gatekeeper module 400 to store the encrypted credit card number in the database and also to create and to assign a unique token to the encrypted credit card number. Again, it should be apparent to one of ordinary skill in the art that in other embodiments other computer modules, besides the gatekeeper module 400 , may perform this task in light of this disclosure. Preferably, the module that is facilitating the saving of the character string to storage also associates the unique token to the string.
[0084] The processor 60 may execute the gatekeeper module 400 (or other module) to create the unique token using various procedures. For example, in various embodiments, the processor 60 executes the gatekeeper module 400 to create the unique token by calling a random number generator module. Random number generator modules typically include an algorithm that can automatically create long runs, e.g., millions of numbers long, with good random properties, however in many cases, the sequence created by the algorithm will eventually repeat. Therefore, once the random number generator module has provided a random number, the processor 60 executes the gatekeeper module 400 to check the provided number against the existing tokens to ensure the acquired random number is unique. The processor 60 executes the gatekeeper module 400 to assign the random number to the encrypted credit card number if the random number is unique. The processor 60 executes the gatekeeper module 400 to discard the random number and re-calls the random number generator module if the random number is not unique.
[0085] Another procedure the gatekeeper module 400 may use in various embodiments to provide unique tokens is to employ database primary keys used to distinguish records in the table of a database. As previously discussed, many commercial database applications include a feature that will allow a field to be defined for a table so that a unique primary key is automatically generated and written into the field for a new record stored in the table. Thus, in the example, when the processor 60 executes the gatekeeper module 400 to store the encrypted credit card number in a table of a database, the database automatically generates a unique primary key and stores the key in the designated field. The processor 60 then executes the gatekeeper module 400 to use this primary key as the unique token associated with the credit card number.
[0086] In various embodiments, the processor 60 executes the gatekeeper module 400 to store the unique token in the same storage as the character string. In other embodiments, the processor 60 executes the gatekeeper module 400 to store the unique token in separate storage. Thus, in the example, the processor 60 executes the gatekeeper module 400 to store the unique token in the same database as the encrypted credit card number or in a separate database.
[0087] In addition, in various embodiments, the processor 60 executes the gatekeeper module 400 to associate a sub-string of the character string with the token in order to identify that the token is associated with the character string without revealing the character string, shown as Step 504 . In various embodiments, the processor 60 executes the gatekeeper module 400 to store this sub-string along with its corresponding token. In other embodiments, the processor 60 executes the gatekeeper module 400 to store the sub-string and token in separate storage. Thus, there is nothing identifiable in the token to link the token to the corresponding character string directly. Instead, the token uses a formal protected cross reference to link to the character string. An example of such a sub-string is the last four digits of a credit card number.
[0088] The use of such a sub-string provides a significant advantage over previous systems. This is because for a previous system to show a user what credit card numbers are stored in the database, the previous system is required to query the database to obtain the credit card numbers, encrypt the credit card numbers if the credit card numbers were decrypted in order to be queried from the database, send the encrypted credit card numbers to a display, such as a webpage, and decrypt the credit card numbers in order to display the numbers to the user. This complex system is required to ensure the security of the information from such threats as hackers, as well as, be in compliance with the PCI DSS guidelines.
[0089] However, in a system 300 that facilitates displaying the stored credit card numbers using a sub-string in conjunction with a token, instead of the actual credit card numbers, the user can view what credit card numbers are stored in the database for him or her without the system 300 actually having to access and transmit the credit card numbers to the display. Therefore, the credit card numbers stay encrypted and secured in the database. As a result, encryption and decryption activities are minimized and the flow of sensitive information is reduced.
[0090] In Step 505 , the processor 60 executes the gatekeeper module 400 to receive a request for the character string, and in response, the processor 60 executes the gatekeeper module 400 to access the string from storage using the unique token associated with the character string according to various embodiments (shown as Step 507 ). The request can be made at various times and from various entities.
[0091] For example, a user may select a particular credit card displayed on the “checkout” webpage to which to charge a purchase and may complete the transaction by selecting the “buy now” button on the page. As previously discussed, a batching module is executed to save the purchase to a database so that the module can later batch the purchase with other purchases made and submitted the purchases to the credit card company for payment. In addition, the batching module is also executed to submit a request to the gatekeeper module 400 for the unique token associated with the credit card number selected by the user to save the token along with the purchase in the database. This provides an advantage over previous systems because by system modules using the unique token instead of the actual credit card number, the credit card number is not exposed to needless risk and the system is not required to perform the complex processing of encrypting and decrypting the credit card information to facilitate the transaction.
[0092] In addition, the processor 60 may also execute the gatekeeper module 400 to verify whether the entity requesting the character string is authorized to receive the character string according to various embodiments of the invention, shown as Step 506 . Thus, the gatekeeper module 400 is provided with formal access controls in various embodiments. For example, the gatekeeper module 400 may comprise an application programming interface (API) executed by a computer to regulate the interaction between independent entities such as computer devices and individuals and the database. Specifically, a device or a user that makes a request to access a character string must first register with the gatekeeper module 400 . Such formal controls provide a mechanism to control who and what can access the credit card numbers in the database.
[0093] In various embodiments, the device or the user will subscribe with the gatekeeper module 400 to gain access to the information stored in the database. As a result, various devices and users may be given various levels of access. For example, the batching module, as previously discussed, will subscribe with the gatekeeper module 400 to be able to submit credit card number requests to the gatekeeper module 400 . Another module, that records and reports a user's transaction history, may only need to retrieve the sub-strings associated with the tokens to display a user's transaction history, and therefore, this module's subscription only provides access to the sub-strings. In addition, the gatekeeper module 400 may provide various other subscription levels, such as privileges to access tokens only.
[0094] Thus, a device or a user will need to provide a token, a sub-string, or some other information and sufficient credentials to the gatekeeper module 400 for the device or the user to gain access to the information in the database. The processor 60 will execute the gatekeeper module 400 to check the device's or the user's credentials to determine if the device or the user is allowed to perform the type of access or manipulation of the information the device or the user wants to perform. In various embodiments, the credentials may take many forms. For example, the processor 60 executes the gatekeeper module 400 to provide a key upon registration to the subscribing device or the subscribing user so that the device or the user may send the key as credentials along with a request. In other embodiments, the processor 60 executes the gatekeeper module 400 to simply check the name of the device or the user against a record in a database table when the module 400 receives the request to determine whether the device or the user has the privilege to perform the request. One of ordinary skill in the art can think of numerous ways of adapting the gatekeeper module 400 to provide and check credentials for a device or a user to establish the device's or the user's level of access to the information in light of this disclosure.
[0095] In addition, the processor 60 also executes the gatekeeper module 400 of various embodiments to monitor the retention of the character strings and associated information stored in the database, shown as Step 509 . Therefore, the processor 60 can execute the gatekeeper module 400 to determine whether any of the sensitive information stored in the database is out-dated and should be deleted or archived from the database. As a result, this will minimize the amount of sensitive information stored in the database and also minimize the liability of storing such information.
[0096] Thus, the processor 60 executes the gatekeeper module 400 to periodically check to determine whether any of the credit card numbers have expired or whether any of the credit card numbers have not been used within a set period of time, e.g., whether a certain period of time has elapsed since the credit card number was last used to make a purchase. Therefore, the processor 60 executes the gatekeeper module 400 to delete a credit card number along with any corresponding information from the database if the credit card number has expired or has not been used within the set period of time, shown as Step 510 . In various embodiments, the processor 60 may also execute the gatekeeper module 400 to archive the credit card number and corresponding information first to an external storage medium, such as a disk or tap drive, before deleting the number and corresponding information from the database, shown as Step 511 .
[0097] The processor 60 can execute the gatekeeper module 400 to monitor the character strings through various techniques. In one embodiment, the processor 60 executes the gatekeeper module 400 to check each record in the database at a certain time each day to determine if any credit card numbers need to be purged from the database, shown as Step 508 . For example, the processor 60 executes a scheduling feature of the gatekeeper module 400 to run every morning at three o'clock a.m. and filters out any records that need to be purged from the database. In another embodiment, the processor 60 executes the gatekeeper module 400 to simply monitor each credit card number stored for a user in response to receiving a request for a particular credit card number associated with the user to determine if any of the user's stored credit card numbers are out of date. In other embodiments, the gatekeeper module 400 does not monitor information retention at all and this task is preformed by another module. One of ordinary skill in the art can envision several techniques in light of this disclosure that may be employed to ensure the character strings and corresponding information is purged if the information has expired.
[0098] At Step 513 , the processor 60 executes the gatekeeper module 400 to transmit the character string to the device or the user requesting the character string according to various embodiments of the invention. As previously discussed, the device or the user making the request can vary. For example, the device or the user may be a program module executed on a computer, a GUI, or an external source such as a credit card company computer system. In addition, the processor 60 can execute the gatekeeper module 400 to provide the character string in various forms. In various embodiments, the processor 60 executes the gatekeeper module 400 to return the character string in a digital format such as in a data stream, a file, or an e-mail or to display the string on a computer monitor. In addition, the processor 60 may need to execute the gatekeeper module 400 to first decrypt the character string (shown as Step 512 ) to provide the string, such as in a standard text format. One of ordinary skill in the art is familiar with the numerous ways the processor 60 can execute the gatekeeper module 400 to transmit the character string to the device or the user requesting the string in light of this disclosure.
[0099] In many instances, the processor 60 also executes the gatekeeper module 400 to receive requests from devices and users to access a unique token associated with a character string. FIG. 6 illustrates a flow diagram related to a gatekeeper module 400 executed by a computer to transmit a unique token associated with a character string according to various embodiments of the invention. This flow diagram may correspond to the steps carried out by a processor 60 in the system 300 shown in FIG. 4 as it executes the gatekeeper module 400 in the RAM memory 67 of the system 300 .
[0100] As previously discussed, in various embodiments, the processor 60 may execute the gatekeeper module 400 to initially obtain a character string from a device or a user. For example, the processor 60 may execute the gatekeeper module 400 to obtain the character string from various entities such as a GUI, a program module executing on a computer system, or other component such as a third-party computer system. However, it should be understood that the gatekeeper module 400 is not the only component that may receive the character string in order to store the string in storage.
[0101] Accordingly, if the gatekeeper module 400 does receive the character string, the processor 60 executes the gatekeeper module 400 to store the character string in storage in the same manner as previously discussed, shown as Step 602 . Thus, in various embodiments, the processor 60 executes the gatekeeper module 400 to store the character string in a database, though in other embodiments, the processor 60 executes the gatekeeper module 400 to store the string in a file, data warehouse, or some type of program module. In addition, various types of storage devices may be used according to various embodiments of the invention. For instance, the storage devices may be internal or external hard drives, storage disks, magnetic tapes, USB flash drives, or some other type of storage devices.
[0102] In many cases the character string represents sensitive information, and therefore, the processor 60 will execute the gatekeeper module 400 to encrypt the string (shown as Step 601 ) or will execute a different module to encrypt the string prior to storing the string. In addition, the processor 60 may execute the gatekeeper module 400 of various embodiments to also obtain additional information to store in the database that is related to the character string.
[0103] Lastly, the processor 60 may execute the gatekeeper module 400 to store the character string in a centralized repository according to various embodiments of the invention. As previously discussed, such a repository may be important in the context of storing sensitive information such as credit card numbers.
[0104] In various embodiments, the processor 60 executes the gatekeeper module 400 to associate a unique token to the character string, as shown in Step 603 . The processor 60 executes the gatekeeper module 400 to associate the unique token with the character string in the same manner as previously discussed above. Thus, in regard to the credit card example, the processor 60 executes the gatekeeper module 400 to create and to assign a unique token to the encrypted credit card number. The gatekeeper module 400 may create the unique token using various procedures. For example, in various embodiments, the processor 60 executes the gatekeeper module 400 to create the unique token by calling a random number generator module or by employing database primary keys used to distinguish records in the table of a database.
[0105] In various embodiments, the processor 60 executes the gatekeeper module 400 to store the unique token in the same storage as the character string. In other embodiments, the processor 60 executes the gatekeeper module 400 to store the unique token in separate storage. Thus, in the credit card example, the processor 60 may execute the gatekeeper module 400 to store the unique token in the same database as the encrypted credit card number or in a separate database.
[0106] In addition, as previously discussed, the processor 60 executes the gatekeeper module 400 to associate a sub-string of the character string associated with the token to identify that the token is associated with the character string without revealing the character string according to various embodiments of the invention, shown as Step 604 . The use of such a sub-string provides a significant advantage over previous systems because it allows a user to operate a computing device to view what character strings are stored in storage without the gatekeeper module 400 (and/or other computer module) having to access, transmit, and display the actual character string to the user. In various embodiments, the processor 60 executes the gatekeeper module 400 to store the sub-string along with its corresponding token. In other embodiments, the processor 60 executes the gatekeeper module 400 to store the sub-string and token in separate storage (e.g., databases).
[0107] In Step 605 , the processor 60 executes the gatekeeper module 400 to receive a request for the unique token, and in response, the processor 60 executes the gatekeeper module 400 to access the token from storage using the character string associated with the token according to various embodiments (shown as Step 606 ). The request can be made at various times and from various entities.
[0108] For example, a user visits a retailer's web site and selects one or more products to purchase. The user is sent by the retailer's web site to a “checkout” webpage to complete the purchase. Once on the “checkout” webpage, the user enters a new credit card number along with information on the “checkout” webpage to which to charge the purchase instead of using a credit card number previously stored. Since this is a new credit card number, the processor 60 executes the gatekeeper module 400 to obtain the credit card number and related information, to encrypt the card number and information, and to save the number and information to the database. In addition, the processor 60 executes the gatekeeper module 400 to generate and to associate a unique token with the new card number.
[0109] As previously discussed, a batching module may also be executed to receive the purchase transaction, and in conjunction to saving the purchase to a database, to send a request to the gatekeeper module 400 for the unique token associated with the new credit card number. The request includes the new credit card number. As a result, the processor 60 executes the gatekeeper module 400 to access the token by using the credit card number provided in the request and to transmit the token back to the batching module. Once the batching module retrieves the unique token associated with the new credit card number, the batching module is executed to save the purchase transaction to a database along with the token as opposed to the new credit card number.
[0110] The processor 60 may also execute the gatekeeper module 400 to verify whether the device or the user requesting the unique token (e.g., the batching module) is authorized to receive the token according to various embodiments of the invention, shown as Step 606 . Thus, in order for a device or a user to gain access to the token, the device or the user will need to provide the character string and sufficient credentials to the gatekeeper module 400 and the processor 60 will execute the module 400 to check whether the device or the user is authorized to access the unique token.
[0111] As previously mentioned the processor 60 executes the gatekeeper module 400 of various embodiments to monitor the retention of the character strings and associated information stored in the database, shown as Step 609 . Thus, the processor 60 will execute the gatekeeper module 400 to periodically check to determine whether any of the credit card numbers have expired or whether any of the credit card numbers have not been used within a set period of time, e.g., whether a certain period of time has elapsed since the credit card number was last used to make a purchase. Therefore, the processor 60 will execute the gatekeeper module 400 to delete a credit card number along with any corresponding information from the database if the credit card number has expired or has not been used within the set period of time, shown as Step 610 . In various embodiments, the processor 60 may also execute the gatekeeper module 400 to archive the credit card number and corresponding information first to an external storage medium, such as a disk or tap drive, before deleting the number and corresponding information from the database, shown as Step 611 .
[0112] The processor 60 can execute the gatekeeper module 400 to monitor the character strings through various techniques. In one embodiment, the processor 60 executes a scheduling feature of the gatekeeper module 400 to check each record in the database at a certain time each day to determine if any credit card numbers need to be purged from the database, shown as Step 608 . In another embodiment, the processor 60 executes the gatekeeper module 400 to simply monitor each credit card number stored for a user in response to receiving a request for a particular token associated with the user to determine if any of the user's stored credit card numbers are out of date. In other embodiments, the processor 60 does not execute the gatekeeper module 400 to monitor information retention at all and this task is preformed by another executed module.
[0113] At Step 612 , the processor 60 executes the gatekeeper module 400 to transmit the unique token to the device or the user requesting the token according to various embodiments of the invention. As previously discussed, the device or the user making the request can vary. For example, the device may be a program module executing on a computer system, a GUI, or an external source such as a credit card company computer system. In addition, the processor 60 can execute the gatekeeper module 400 to provide the token in various forms. In various embodiments, the processor 60 executes the gatekeeper module 400 to return the token in a digital format such as in a data stream, a file, or an e-mail or to display the token on a computer monitor. One of ordinary skill in the art is familiar with the numerous ways the gatekeeper module 400 can provide the token to the device or the user requesting the token in light of this disclosure.
[0114] Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. | Various embodiments of the present invention are directed to methods, systems and computer program products for conducting an online transaction on a website involving sensitive information. Such embodiments provide methods, systems and computer program products to: (a) register at least one entity with a gate keeper module, the registering comprising associating the entity with a subscription level; (b) associate a sub-string of a character string with a unique token so that a direct link does not exist between the unique token and the character string; and (c) during processing of the online transaction: (i) using the unique token for intermediate steps during the processing of the online transaction; and (ii) only accessing the character string in storage memory to complete the online transaction after receiving a request from at least one registered entity associated with a subscription level associated with a privilege to receive the requested sensitive information. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a temperature control method for a refrigerator, and more particularly to a temperature control method for a refrigerator which can supply cold air to insufficiently cooled regions in a refrigerating compartment of the refrigerator without an additional turning-on of a compressor and circulating fan included in the refrigerator, thereby being capable of minimizing a temperature deviation of the refrigerating compartment while minimizing the power consumption of the refrigerator.
2. Description of the Related Art
Generally, a refrigerator is an apparatus in which freezing and refrigerating compartments are maintained at desired low temperatures by a refrigerant cooling cycle consisting of a compressor, a condenser, a capillary valve, and an evaporator.
FIG. 1 is a perspective view of a conventional refrigerator, illustrating the condition in which freezing and refrigerating compartments are in an opened state.
As shown in FIG. 1 , the conventional refrigerator includes a refrigerator body in which a freezing compartment F and a refrigerating compartment R are defined by a barrier 2 at opposite sides of the barrier 2 , respectively. A freezing compartment door 4 is hingably mounted to the refrigerator body in front of the freezing compartment F. A refrigerating compartment door 6 is also hingably mounted to the refrigerator body in front of the refrigerating compartment R.
FIG. 2 is a front view showing the inner structure of the conventional refrigerator. FIG. 3 is a side view showing the inner structure of the refrigerating compartment in the conventional refrigerator.
An evaporator 8 is installed in rear of the freezing compartment F. The evaporator 8 absorbs heat from air in the freezing compartment F or refrigerating compartment R through heat exchange between the air and a refrigerant passing through the evaporator 8 . In accordance with the heat absorption, the refrigerant evaporates. A circulating fan 10 is also installed in rear of the freezing compartment F in order to forcibly convect the air, cooled in accordance with the heat absorption of the evaporator 8 , into the freezing compartment F or refrigerating compartment R.
The freezing compartment F is provided, at the upper portion of a rear wall thereof, with cold air discharge holes 12 adapted to discharge the air cooled by the evaporator 8 , that is, cold air, into the freezing compartment F in accordance with the operation of the circulating fan 10 . The freezing compartment F is also provided, at the lower portion of the rear wall thereof, with cold air return holes 14 adapted to return the cold air, used to cool the freezing compartment F to a desired freezing temperature, to the evaporator 8 .
The freezing compartments F is partitioned into a plurality of freezing chambers F 1 to F 6 . A plurality of shelves 15 to 19 are installed in the freezing chamber F such that they are vertically spaced apart from one another. Food or containers may be laid on the shelves 15 to 19 .
The barrier 2 is provided, at its upper portion, with a cold air discharge duct 21 for partially discharging the cold air produced by the evaporator 8 into the refrigerating compartment R in accordance with the operation of the circulating fan 10 . The barrier 2 is also provided, at its lower portion, with a cold air return duct 22 for returning the cold air, used to cool the freezing compartment F to a desired freezing temperature, to the evaporator 8 .
A damper 24 is installed at one side of the cold air discharge duct 21 or at the upper portion of the refrigerating compartment R. The damper 24 is opened or closed to determine whether nor not the cold air has to be discharged into the refrigerating compartment R.
On the other hand, the refrigerating compartment R is partitioned into a plurality of refrigerating chambers R 1 to R 6 . A plurality of refrigerating compartment shelves 25 to 28 are installed in the refrigerating chamber R such that they are vertically spaced apart from one another. Food or containers may be laid on the refrigerating compartment shelves 25 to 28 .
A plurality of baskets 31 to 35 adapted to receive food or containers are mounted to the back surface of the refrigerating compartment door 6 such that they are vertically spaced apart from one another.
The refrigerating compartment shelves 25 to 29 are spaced apart from the baskets 31 to 35 respectively arranged adjacent thereto and from the back surface of the refrigerating compartment door 6 , so as to define a cold air passage.
The reference numeral 44 designates a freezing compartment temperature sensor for sensing a temperature at one side of the freezing compartment F, and the reference numeral 45 designates a refrigerating compartment temperature sensor for sensing a temperature at one side of the refrigerating compartment R.
FIG. 4 is a control block diagram of the conventional refrigerator.
As shown in FIG. 3 , the conventional refrigerator further includes a compressor 41 for compressing a gaseous refrigerant of low temperature and low pressure emerging from the evaporator 8 , thereby producing a gaseous refrigerant of high temperature and high pressure, a condenser for discharging heat from the gaseous refrigerant of high temperature and high pressure into the atmosphere, thereby condensing the gaseous refrigerant to produce a liquid refrigerant of intermediate temperature and high pressure, a capillary valve for reducing the pressure of the high-pressure liquid refrigerant emerging from the condenser, and a compressor cooling fan 42 for cooling the compressor 41 in order to prevent the compressor 41 from over-heating.
The refrigerator also includes a temperature setting unit 43 for setting predetermined maximum and minimum temperatures of the freezing and refrigerating compartments F and R, and a control unit 46 for comparing sensed temperatures of the freezing and refrigerating compartments F and R with the predetermined maximum and minimum temperatures associated therewith, respectively, thereby controlling the opening/closing of the damper 24 and the turning-on/off of the circulating fan 10 , compressor 41 , and compressor cooling fan 42 .
The predetermined maximum and minimum temperatures may be set to correspond to a temperature obtained by adding a predetermined temperature tolerance to a desired temperature set by the user, and a temperature obtained by deducting the predetermined temperature tolerance from the set temperature, respectively. Alternatively, the predetermined maximum and minimum temperatures may be independently set.
Now, a temperature control method for the conventional refrigerator having the above mentioned configuration will be described.
FIG. 5 is a flow chart illustrating the temperature control method for the conventional refrigerator.
First, the control unit 46 compares the temperature T f of the freezing compartment F sensed by the freezing compartment temperature sensor 44 with the predetermined maximum temperature T f max of the freezing compartment F (S 1 ).
The predetermined maximum freezing compartment temperature T f max corresponds to a temperature obtained by adding a predetermined temperature tolerance to a desired freezing compartment temperature set by the user.
The control unit 46 turns on the circulating fan 10 , compressor 41 , and compressor cooling fan 42 when it determines that the temperature T f of the freezing compartment F is equal to or more than the predetermined maximum temperature T f max of the freezing compartment F (S 2 ).
When the circulating fan 10 and compressor 41 are turned on, air present in the freezing compartment F circulates between the evaporator 20 and the freezing compartment F, thereby causing the freezing compartment F to be cooled to a desired freezing temperature.
Thereafter, the control unit 46 compares the temperature T r of the refrigerating compartment R sensed by the refrigerating compartment temperature sensor 45 with the predetermined maximum temperature T r max of the refrigerating compartment R (S 3 ).
The predetermined maximum refrigerating compartment temperature T r max corresponds to a temperature obtained by adding a predetermined temperature tolerance to a desired refrigerating compartment temperature set by the user.
The control unit 46 opens the damper 24 when it determines that the temperature T r of the refrigerating compartment R is equal to or more than the predetermined maximum temperature T r max of the refrigerating compartment R (S 4 ).
When the damper 24 is opened, a part of the air cooled by the evaporator 8 is discharged into the refrigerating compartment R via the cold air discharge duct 21 . The discharged cold air cools the interior of the refrigerating compartment R to a desired refrigerating temperature while being convected in the interior of the refrigerating compartment R. Subsequently, the cold air flows toward the lower portion of the refrigerating compartment R, and then returns to the evaporator 8 through the cold air return duct 22 .
On the other hand, if it is determined at step S 3 that the temperature T r of the refrigerating compartment R is less than the predetermined maximum temperature T r max of the refrigerating compartment R, the control unit 46 then compares the temperature T r of the refrigerating compartment R with the predetermined minimum temperature T r min of the refrigerating compartment R (S 5 ).
The predetermined minimum refrigerating compartment temperature T r min corresponds to a temperature obtained by deducting a predetermined temperature tolerance to a desired refrigerating compartment temperature set by the user.
The control unit 46 closes the damper 24 when it determines that the temperature T r of the refrigerating compartment R is less than the predetermined minimum temperature T r min of the refrigerating compartment R (S 6 ).
When the damper 24 is closed, the cold air is discharged into the refrigerating compartment R no longer. Accordingly, the interior of the refrigerating compartment R is not over-cooled.
On the other hand, if it is determined at step S 1 that the temperature T f of the freezing compartment F is less than the predetermined maximum temperature T f max of the freezing compartment F, the control unit 46 then compares the temperature T f of the freezing compartment F with the predetermined minimum temperature T f min of the freezing compartment F (S 7 ).
The predetermined minimum freezing compartment temperature T f min corresponds to a temperature obtained by deducting a predetermined temperature tolerance to a desired freezing compartment temperature set by the user.
When it is determined that the temperature T f of the freezing compartment F is less than the predetermined maximum temperature T f max of the freezing compartment F, the control unit 46 turns off the compressor 41 and compressor cooling fan 42 .
In the OFF state of the compressor 41 , the refrigerant temperature of the evaporator 20 increases with the lapse of time. As a result, the temperature of the cold air circulating between the freezing compartment F and the evaporator 8 is increased due to a load in the freezing compartment F, so that the interior of the freezing compartment F is not over-cooled.
Thereafter, the control unit 46 again compares the temperature T r of the refrigerating compartment R sensed by the refrigerating compartment temperature sensor 45 with the predetermined maximum temperature T r max of the refrigerating compartment R (S 9 ).
When it is determined that the temperature T r of the refrigerating compartment R is equal to or more than the predetermined maximum temperature T r max of the refrigerating compartment R, the control unit 46 again opens the damper 24 , and again turns on the circulating fan (S 10 ).
When the damper 24 is opened, and the circulating fan 10 is turned on, a part of the air cooled by the evaporator 8 is discharged into the refrigerating compartment R via the cold air discharge duct 21 . The discharged cold air cools the interior of the refrigerating compartment R to a desired refrigerating temperature while being convected in the interior of the refrigerating compartment R. Subsequently, the cold air flows toward the lower portion of the refrigerating compartment R, and then returns to the evaporator 8 through the cold air return duct 22 .
On the other hand, if it is determined at step S 9 that the temperature T r of the refrigerating compartment R is less than the predetermined maximum temperature T r max of the refrigerating compartment R, the control unit 46 then again compares the temperature T r of the refrigerating compartment R with the predetermined minimum temperature T r min of the refrigerating compartment R (S 11 ).
The control unit 46 again closes the damper 24 and turns off the circulating fan 10 when it determines that the temperature T r of the refrigerating compartment R is less than the predetermined minimum temperature T r min of the refrigerating compartment R (S 12 ).
When the damper 24 is closed, and the circulating fan 10 is turned off, the cold air is discharged into the refrigerating compartment R no longer. Accordingly, the interior of the refrigerating compartment R is not over-cooled.
However, the above mentioned convention refrigerator temperature control method has a limitation in uniformly convecting the cold air, discharged into the refrigerating compartment R, in the interior of the refrigerating compartment R. For this reason, in the refrigerating compartment R, there may be an insufficiently cooled region where convection of the cold air is ineffectively carried out. As a result, there may be a temperature deviation in the refrigerating compartment R.
In order to eliminate such a temperature deviation in the refrigerating compartment R, a proposal for separately discharging cold air into the insufficiently cooled region has been made. In accordance with this proposal, a second cold air discharge duct is provided in the interior of the barrier 2 , and a nozzle is connected to the second cold air discharge duct while being arranged such that it injects cold air into the insufficiently cooled region. In accordance with such a configuration, it is possible to more or less reduce the temperature deviation of the refrigerating compartment R caused by the non-uniform cold air convection. However, such a temperature deviation reduction is low in a state in which both the nozzle and the damper 24 are opened.
SUMMARY OF THE INVENTION
The present invention has been made in view of the above mentioned problems involved with the related art, and an object of the invention is to provide a temperature control method for a refrigerator which can minimize a deviation in refrigerant compartment temperature while minimizing the power consumption of the refrigerator.
In accordance with one aspect, the present invention provides a temperature control method for a refrigerator comprising the steps of: (A) comparing a sensed temperature of a freezing compartment defined in the refrigerator with a predetermined maximum freezing compartment temperature and a predetermined minimum freezing compartment temperature, respectively, thereby controlling a compressor and a circulating fan included in the refrigerator to be turned on or off such that the sensed freezing compartment temperature is ranged between the predetermined maximum and minimum freezing temperatures; (B) comparing, following the step (A), a sensed temperature of a refrigerating compartment, defined in the refrigerator while being defined with a plurality of refrigerating chambers therein, with a predetermined maximum refrigerating compartment temperature and a predetermined minimum refrigerating compartment temperature, respectively, thereby controlling a damper included in the refrigerator to be opened or closed and the circulating fan to be turned on or off such that the sensed refrigerating compartment temperature is ranged between the predetermined maximum and minimum refrigerating temperatures; and (C) discharging cold air into at least one of the refrigerating chambers when the damper is closed at the step (B) under a condition in which the compressor and the circulating fan are turned on at the step (A).
In accordance with another aspect, the present invention provides a temperature control method for a refrigerator comprising the steps of: (A) comparing a sensed temperature of a freezing compartment defined in the refrigerator with a predetermined maximum freezing compartment temperature and a predetermined minimum freezing compartment temperature, respectively, thereby controlling a compressor and a circulating fan included in the refrigerator to be turned on or off such that the sensed freezing compartment temperature is ranged between the predetermined maximum and minimum freezing temperatures; (B) comparing, following the step (A), a sensed temperature of a refrigerating compartment, defined in the refrigerator while being defined with a plurality of refrigerating chambers therein, with a predetermined maximum refrigerating compartment temperature and a predetermined minimum refrigerating compartment temperature, respectively, thereby controlling a damper included in the refrigerator to be opened or closed and the circulating fan to be turned on or off such that the sensed refrigerating compartment temperature is ranged between the predetermined maximum and minimum refrigerating temperatures; and (C) discharging cold air into at least one of the refrigerating chambers in response to an opening signal outputted from a nozzle timer included in the refrigerator when the damper is closed at the step (B) under a condition in which the compressor and the circulating fan are turned on at the step (A).
BRIEF DESCRIPTION OF THE DRAWINGS
The above objects, and other features and advantages of the present invention will become more apparent after reading the following detailed description when taken in conjunction with the drawings, in which:
FIG. 1 is a perspective view of a conventional refrigerator, illustrating the condition in which freezing and refrigerating compartments are in an opened state;
FIG. 2 is a front view showing the inner structure of the conventional refrigerator;
FIG. 3 is a side view showing the inner structure of the refrigerating compartment in the conventional refrigerator;
FIG. 4 is a control block diagram of the conventional refrigerator;
FIG. 5 is a flow chart illustrating a temperature control method for the conventional refrigerator;
FIG. 6 is a front view illustrating the inner structure of a refrigerator according to the present invention;
FIG. 7 is a side view illustrating the inner structure of a refrigerating compartment in the refrigerator according to the present invention;
FIG. 8 is a control block diagram of the refrigerator according to the present invention;
FIG. 9 is a flow chart illustrating a temperature control method for the refrigerator having the above described configuration in accordance with an embodiment of the present invention; and
FIG. 10 is a timing diagram illustrating operations of the refrigerator carried out in accordance with the temperature control method of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now, preferred embodiments of the present invention will be described in detail with reference to the annexed drawings.
FIG. 6 is a front view illustrating the inner structure of a refrigerator according to the present invention. FIG. 7 is a side view illustrating the inner structure of a refrigerating compartment in the refrigerator according to the present invention.
The refrigerator of the present invention shown in FIGS. 6 and 7 has the same basic structure as that of the conventional refrigerator shown in FIGS. 2 and 3 . Constituent elements included in the basic structure shown in FIGS. 6 and 7 are designated by the same reference numerals as those of FIGS. 2 and 3 , respectively, and no detailed description thereof will be given. In the refrigerator of the present invention, as shown in FIGS. 6 and 7 , a second cold air discharge duct 52 is formed at the barrier 2 such that it communicates, at one end thereof, with the cold air discharge duct 21 while communicating, at the other end thereof, with a part of the refrigerating chambers R 1 to R 6 , for example, the refrigerating chambers R 2 , R 3 , and R 4 . Nozzles 62 to 64 are mounted to the other end of the second cold air discharge duct 52 in order to inject cold air, passing through the second cold air discharge duct 52 , into the refrigerating chambers R 2 to R 4 , respectively. Nozzle motors 72 to 74 are coupled to respective nozzles 62 to 64 . Each of the nozzle motors 72 to 74 serves to rotate an associated one of the nozzles 62 to 64 between a closed position where the outlet of the associated nozzle is directed toward the barrier 2 and an opened position where the outlet of the associated nozzle is directed toward an associated one of the refrigerating chamber R 2 to R 4 . The refrigerator of the present invention has the same structure as that of the conventional refrigerator, except for the second cold air discharge duct 52 , nozzles 62 to 64 , and nozzle motors 72 to 74 .
FIG. 8 is a control block diagram of the refrigerator according to the present invention.
Under the condition in which both the circulating fan 10 and the compressor 41 are in their ON state, and the damper 24 is in its closed state, the control unit 46 turns on the nozzle motors 72 to 74 in order to open respective outlets of the nozzles 62 to 64 .
The refrigerator according to the illustrated embodiment of the present invention further includes a nozzle timer 82 for periodically outputting an opening signal and a closing signal in order to open and close the nozzles 62 to 64 at intervals of a predetermined time. When the nozzle timer 82 outputs an opening signal under the condition in which both the circulating fan 10 and the compressor 41 are in their ON state, and the damper 24 is in its closed state, the control unit 46 turns on the nozzle motors 72 to 74 to open respective outlets of the nozzles 62 to 64 .
FIG. 9 is a flow chart illustrating a temperature control method for the refrigerator having the above described configuration in accordance with an embodiment of the present invention.
First, the control unit 46 compares the temperature T f of the freezing compartment F sensed by the freezing compartment temperature sensor 44 with the predetermined maximum temperature T f max of the freezing compartment F (S 11 ).
When it is determined at step S 11 that the temperature T f of the freezing compartment F is equal to or more than the predetermined maximum temperature T f max of the freezing compartment F, the control unit 46 turns on the circulating fan 10 and compressor 41 (S 12 ).
The control unit 46 also turns on the compressor cooling fan 42 , simultaneously with the turning-on of the compressor 41 .
When the circulating fan 10 and compressor 41 are turned on, air present in the freezing compartment F circulates between the evaporator 20 and the freezing compartment F, thereby causing the freezing compartment F to be cooled to a desired freezing temperature.
Thereafter, the control unit 46 compares the temperature T r of the refrigerating compartment R sensed by the refrigerating compartment temperature sensor 45 with the predetermined maximum temperature T r max of the refrigerating compartment R (S 13 ).
The control unit 46 opens the damper 24 when it determines that the temperature T r of the refrigerating compartment R is equal to or more than the predetermined maximum temperature T r max of the refrigerating compartment R (S 14 ).
When the damper 24 is opened, a part of the air cooled by the evaporator 8 is discharged into the upper portion of the refrigerating compartment R via the cold air discharge duct 21 . The discharged cold air cools the interior of the refrigerating compartment R to a desired refrigerating temperature while being convected in the interior of the refrigerating compartment R. Subsequently, the cold air flows toward the lower portion of the refrigerating compartment R, and then returns to the evaporator 8 through the cold air return duct 22 .
During the above operation, the control unit 46 also controls the nozzle motors 72 to 74 to cause respective outlets of the nozzles 62 to 64 to are directed toward the barrier 2 , irrespective of an opening/closing signal from the nozzle timer 82 (S 15 ). Accordingly, the nozzles 62 to 64 are maintained in their closed state.
In the closed state of the nozzles 62 to 64 , the cold air passing through the cold air discharge duct 21 cannot be injected into the refrigerating chambers R 2 , R 3 , and R 4 through the nozzles 62 to 64 . That is, the whole part of the cold air is discharged into the upper portion of the refrigerating compartment R. The cold air introduced into the refrigerating compartment R cools the interior of the refrigerating compartment R to a desired refrigerating temperature while being convected throughout the interior of the refrigerating compartment R.
On the other hand, if it is determined at step S 13 that the temperature T r of the refrigerating compartment R is less than the predetermined maximum temperature T r max of the refrigerating compartment R, the control unit 46 then compares the temperature T r of the refrigerating compartment R with the predetermined minimum temperature T r min of the refrigerating compartment R (S 16 ).
The control unit 46 closes the damper 24 when it determines that the temperature T r of the refrigerating compartment R is less than the predetermined minimum temperature T r min of the refrigerating compartment R (S 17 ).
When the damper 24 is closed, the cold air is discharged into the refrigerating compartment R no longer. Accordingly, the interior of the refrigerating compartment R is not over-cooled.
Meanwhile, under the condition in which both the circulating fan 10 and the compressor 41 are in their ON state, and the damper 24 is in its closed state, the control unit 46 controls the nozzle motors 72 to 74 to cause respective outlets of the nozzles 62 to 64 to be directed toward the refrigerating chambers R 2 , R 3 , and R 4 (S 19 ). In this state, the nozzles 62 to 64 are opened.
Alternatively, the control unit 46 may be configured to control the nozzle motors 72 to 74 to cause respective outlets of the nozzles 62 to 64 to be directed toward the refrigerating chambers R 2 , R 3 , and R 4 , in response to an opening signal outputted from the nozzle timer 82 under the condition in which both the circulating fan 10 and the compressor 41 are in their ON state, and the damper 24 is in its closed state (S 18 and S 19 ).
That is, it may be possible to determine whether or not the nozzles 62 to 64 have to be opened, only based on the states of the circulating fan 10 , compressor 41 , and damper 24 . Alternatively, this determination may be achieved, based on the operation of the nozzle timer 82 in addition to the states of the circulating fan 10 , compressor 41 , and damper 24 .
When the nozzles 62 to 64 are opened, the cold air, which has been confined in the second cold air discharge duct 52 due to the closed state of the damper 24 , is discharged into the refrigerating chambers R 2 , R 3 and R 4 through the opened nozzles 62 to 64 , respectively.
The discharged cold air cools the refrigerating chambers R 2 , R 3 , and R 4 to a desired refrigerating temperature. Subsequently, the cold air flows toward the lower portion of the refrigerating compartment R, and then returns to the evaporator 8 through the cold air return duct 22 .
Thus, it is possible to cool, to a desired refrigerating temperature, insufficiently cooled regions formed when the temperature T r of the refrigerating compartment R is less than the predetermined maximum temperature T r max of the refrigerating compartment R, without additional operations of the compressor 41 and circulating fan 10 .
When the control unit 46 is configured to take into consideration the opening/closing signal outputted from the nozzle timer 82 in determining the opening/closing of the nozzles 62 to 64 , it controls the nozzle motors 72 to 74 so that the outlets of the nozzles 62 to 64 are directed toward the barrier 2 in response to a closing signal outputted from the nozzle timer 82 , even when both the circulating fan 10 and the compressor 41 are in their ON state, and the damper 24 is in its closed state (S 18 and S 20 ).
In the closed state of the nozzles 62 to 64 , no cold air is discharged into the refrigerating chambers R 2 , R 3 and R 4 through the nozzles 62 to 64 . Accordingly, the refrigerating chambers R 2 , R 3 , and R 4 are not over-cooled.
Thus, it is possible to minimize the temperature deviation of the refrigerating compartment while preventing the insufficiently cooled regions from being over-cooled, by discharging cold air into the insufficiently cooled regions only in response to an opening signal outputted from the nozzle timer 82 , that is, only when the nozzle timer 82 is in its ON state.
On the other hand, if it is determined at step S 11 that the temperature T f of the freezing compartment F is less than the predetermined maximum temperature T f max of the freezing compartment F, the control unit 46 then compares the temperature T f of the freezing compartment F with the predetermined minimum temperature T f min of the freezing compartment F (S 21 ).
When it is determined that the temperature T f of the freezing compartment F is less than the predetermined maximum temperature T f max of the freezing compartment F, the control unit 46 turns off the compressor 41 .
The control unit 46 also turns off the compressor cooling fan 42 , simultaneously with the turning-off of the compressor 41 .
In the OFF state of the compressor 41 , the refrigerant temperature of the evaporator 20 increases with the lapse of time. As a result, the temperature of the cold air circulating between the freezing compartment F and the evaporator 8 is increased due to a load in the freezing compartment F, so that the interior of the freezing compartment F is not over-cooled.
Thereafter, the control unit 46 again compares the temperature T r of the refrigerating compartment R sensed by the refrigerating compartment temperature sensor 45 with the predetermined maximum temperature T r max of the refrigerating compartment R (S 23 ).
When it is determined that the temperature T r of the refrigerating compartment R is equal to or more than the predetermined maximum temperature T r max of the refrigerating compartment R, the control unit 46 again opens the damper 24 , and again turns on the circulating fan (S 24 ).
When the damper 24 is opened, and the circulating fan 10 is turned on, a part of the air cooled by the evaporator 8 is discharged into the refrigerating compartment R via the cold air discharge duct 21 . The discharged cold air cools the interior of the refrigerating compartment R to a desired refrigerating temperature while being convected in the interior of the refrigerating compartment R. Subsequently, the cold air flows toward the lower portion of the refrigerating compartment R, and then returns to the evaporator 8 through the cold air return duct 22 .
During the above operation, the control unit 46 also controls the nozzle motors 72 to 74 to cause respective outlets of the nozzles 62 to 64 to be directed toward the barrier 2 , irrespective of an opening/closing signal from the nozzle timer 82 (S 25 ). Accordingly, the nozzles 62 to 64 are maintained in their closed state.
In the closed state of the nozzles 62 to 64 , the cold air passing through the cold air discharge duct 21 cannot be injected into the refrigerating chambers R 2 , R 3 , and R 4 through the nozzles 62 to 64 . That is, the whole part of the cold air is discharged into the upper portion of the refrigerating compartment R. The cold air introduced into the refrigerating compartment R cools the interior of the refrigerating compartment R to a desired refrigerating temperature while being convected throughout the interior of the refrigerating compartment R.
On the other hand, if it is determined at step S 23 that the temperature T r of the refrigerating compartment R is less than the predetermined maximum temperature T r max of the refrigerating compartment R, the control unit 46 then compares the temperature T r of the refrigerating compartment R with the predetermined minimum temperature T r min of the refrigerating compartment R (S 26 ).
The control unit 46 closes the damper 24 while turning off the circulating fan 10 when it determines that the temperature T r of the refrigerating compartment R is less than the predetermined minimum temperature T r min of the refrigerating compartment R (S 27 ).
When the damper 24 is closed, and the circulating fan 10 is turned off, the cold air is discharged into the refrigerating compartment R no longer. Accordingly, the interior of the refrigerating compartment R is not over-cooled.
Since the circulating fan 10 is in its OFF state, the control unit 46 controls the nozzle motors 72 to 74 so that respective outlets of the nozzles 62 to 64 are directed toward the barrier 2 , irrespective of an opening/closing signal from the nozzle timer 82 (S 15 ). Accordingly, the nozzles 62 to 64 are maintained in their closed state.
In the closed state of the nozzles 62 to 64 , the cold air passing through the cold air discharge duct 21 cannot be injected into the refrigerating chambers R 2 , R 3 , and R 4 through the nozzles 62 to 64 . Accordingly, the refrigerating chambers R 2 , R 3 , and R 4 are not over-cooled.
That is, when the circulating fan 10 is turned off in the closed state of the damper 24 , the nozzles 62 to 64 are closed in spite of the closed state of the damper 24 . Accordingly, it is possible to prevent the nozzle motors 72 to 74 from operating unnecessarily, thereby preventing an unnecessary increase in power consumption.
The ON/OFF timing of the compressor 41 , circulating fans 10 , and damper 24 , and the opening/closing timing of the nozzles 62 to 64 are shown in FIG. 10 .
FIG. 10 is a timing diagram illustrating operations of the refrigerator carried out in accordance with the temperature control method of the present invention.
In FIG. 10 , “P 1 ”, “P 2 ” and “P 3 ” are periods in which cold air is discharged through the nozzles 62 to 64 , respectively. In the periods P 1 , P 2 , and P 3 , the circulating fan 10 , compressor 41 , and nozzle timer 82 are in their ON state, whereas the damper 24 is in its OFF (closed) state.
The ON/OFF states of the compressor 41 , circulating fans 10 , and damper 24 , and the opening/closing state of the nozzles 62 to 64 have a relation shown in Table 1.
TABLE 1
Compressor
Circulating Fan
Damper
Nozzles
ON
ON
ON
Closed
ON
ON
OFF
Opened
OFF
ON
ON
Closed
OFF
OFF
OFF
Closed
As shown in Table 1 and FIG. 10 , cold air is discharged into the insufficiently cooled regions of the refrigerating compartment R when the circulating fan 10 and compressor 41 are in their ON state, and the damper 24 is in its OFF state, or when the nozzle timer is in its ON state under the condition in which the circulating fan 10 and compressor 41 are in their ON state, and the damper 24 is in its OFF state. Accordingly, it is possible to reduce the temperature deviation of the refrigerating compartment R without an additional turning-on of the circulating fan 10 and compressor 41 .
As apparent from the above description, in accordance with the refrigerator temperature control method according to the present invention, cold air is discharged into a part of the refrigerating chambers when the circulating fan and compressor are in their ON state, and the damper is in its OFF state. Accordingly, it is possible to reduce a temperature deviation occurring in the refrigerating compartment. Also, such a temperature deviation reduction can be achieved in accordance with opening/closing of the nozzles without additional operations of the compressor and circulating fan. Accordingly, an improvement in power consumption efficiency can be achieved.
Also, cold air may be discharged into a part of the refrigerating chambers in response to an opening signal outputted from the nozzle timer under the condition in which the circulating fan and compressor are in their ON state, and the damper is in its OFF state. In this case, there is an advantage in that it is possible to prevent the refrigerating chambers, supplied with the cold air through the nozzles, from being over-cooled.
Although the preferred embodiments of the invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. | Disclosed is a temperature control method for a refrigerator which can minimize a deviation in refrigerant compartment temperature while minimizing the power consumption of the refrigerator. The temperature control method includes the steps of (A) comparing a sensed temperature of a freezing compartment with a predetermined maximum freezing compartment temperature and a predetermined minimum freezing compartment temperature, respectively, thereby controlling a compressor and a circulating fan to be turned on or off such that the sensed freezing compartment temperature is ranged between the predetermined maximum and minimum freezing temperatures, (B) comparing, following the step (A), a sensed temperature of a refrigerating compartment defined with a plurality of refrigerating chambers therein, with a predetermined maximum refrigerating compartment temperature and a predetermined minimum refrigerating compartment temperature, respectively, thereby controlling a damper to be opened or closed and the circulating fan to be turned on or off such that the sensed refrigerating compartment temperature is ranged between the predetermined maximum and minimum refrigerating temperatures, and (C) discharging cold air into at least one of the refrigerating chambers when the damper is closed, and the compressor and the circulating fan are turned on. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of Invention
[0002] This invention is in the general field of highway warning devices and, more particularly, is a hazard marker that provides an aimed illumination.
[0003] 2. Description of the Prior Art
[0004] A hazard marker is typically placed near a problem area created by a mishap that occurs on either a street or a highway. Reasons for placing the marker include protection of people against injury, discouraging people from either walking or driving in the problem area, discouraging intrusion into emergency medical treatment of injuries resulting from the mishap and discouraging intrusion into clean up activity. The hazard marker may, for example, be a flare, a sequentially illuminated arrow, a message sign, a wooden barricade that carries a blinking warning light or an orange cone.
[0005] The flare has an advantage of being easily visible at night. However, a motorist who drives past one or more flares may be temporarily blinded by their brightness, thereby endangering the motorist and people in the vicinity of the motorist. The flare is particularly dangerous to use where an automobile collision causes a spillage of gasoline on a roadway. Among other undesirable aspects of the flare is that a person charged with igniting the flare risks being burned and having their clothing burned. The flare additionally releases noxious fumes when it bums.
[0006] The orange cone is one of the most commonly used hazard markers. The cone frequently has a light and a battery mounted near its apex. The light cannot readily be seen outside of an immediate area where the cone is placed, particularly in poor weather conditions. The light and the battery make the cone top heavy, thereby destabilizing the cone. Even in the absence of the destabilizing, the cone is frequently destroyed or badly damaged when inadvertently struck by a motor vehicle.
[0007] Practically all hazard markers are either badly damaged or destroyed when struck by the motor vehicle; additionally, the motor vehicle is frequently damaged. Thus there is a need for a new type of hazard marker that is neither damaged nor causes damage when struck by the automobile, provides light that can be seen outside of an immediate area where the new type of marker is placed and does not temporarily blind a passing motorist with its brightness.
SUMMARY OF THE INVENTION
[0008] According to one aspect of the present invention, a turbo flare hazard marker in the general shape of a disc includes a transparent upper housing and a lower housing that are made from a high impact plastic. Each of three or more similar legs of the marker are made from a plastic plate that is connected to an outer edge of the lower housing and extends radially therefrom. A foot of each of the legs extends below a bottom surface of the lower housing.
[0009] According to a second aspect of the present invention, the turbo flare hazard marker includes a plurality of light emitting diodes (LEDs) that have a circular disposition within the housing. The LEDs are oriented either to provide light that can be seen by a motorist at a substantial distance from the turbo hazard flare marker or provide light that can be seen by an aircraft flying above the turbo hazard marker.
[0010] According to a third aspect of the invention, an oscillator drives an input of a ring counter. Outputs of the ring counter sequentially drive the LEDs. Current through the LEDs passes through a sampling resistor, thereby providing a sampling voltage. A reference voltage is compared to the sampling voltage. An excitation voltage applied to the ring counter is changed in response to a difference between the reference voltage and the sampling voltage. The change in the excitation causes a corresponding change in the drive at the output of the ring counter that results in the reference and sampling voltages being substantially equal.
[0011] The turbo flare hazard marker is of a construction that is neither damaged by a motor vehicle nor causes damage to the motor vehicle, provides light that can be seen outside of its immediate area and does not blind a passing motorist with its brightness.
[0012] Other objects, features, and advantages of the invention should be apparent from the following description of the preferred embodiment thereof as illustrated in the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
[0013] [0013]FIG. 1 is a perspective view of the preferred embodiment of the present invention;
[0014] [0014]FIG. 2 is a plan view of the embodiment of FIG. 1;
[0015] [0015]FIG. 3 is a perspective view of a circuit board in the embodiment of FIG. 1;
[0016] [0016]FIG. 4 is a perspective view of the interior of a housing in the embodiment of FIG. 1;
[0017] [0017]FIG. 5 is a section view of a lid of a housing in FIG. 1 taken along the line 5 - 5 ;
[0018] [0018]FIG. 6 is a side elevation of hazard markers mounted upon a charging stick;
[0019] [0019]FIG. 7 is a schematic showing of elements that cause a sequential illumination of LEDS in the embodiment of FIG. 1; and
[0020] [0020]FIG. 8 is a timing diagram applicable to the schematic of FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] As shown in FIGS. 1 and 2, a turbo hazard marker 10 has a general shape of a disc. The marker 10 includes a lower housing 12 and an upper housing 14 that are made from a high impact plastic. The upper housing 14 is transparent. A plurality of bolts 16 pass through the upper housing 14 and a bottom 18 of the lower housing 12 where they screw into nuts (not shown), whereby the lower housing 12 and the upper housing 14 are held together.
[0022] Visible through the upper housing 14 is a printed circuit board 19 whereon LEDs 20 -A through 20 -T are circularly disposed proximal to a wall 14 V of the housing 14 . As explained hereinafter, the LEDs 20 -A through 20 -T transmit light through the wall 14 V.
[0023] The hazard marker 10 includes a leg 21 A that has general shape of a right triangular slab. A side 22 A (FIG. 1) of the leg 21 A is connected to a side 24 of the lower housing 12 . The leg 21 A extends radially from the hazard marker 10 . Because of its size, the leg 21 A extends to a level below the bottom 18 whereby a ramp edge 22 R of the leg 21 A extends from below a level of the bottom 18 to the upper housing 14 .
[0024] The leg 21 A includes a foot 22 F that extends from an end of the ramp edge 22 R to the side 22 A. The foot 22 F has a V shaped cross section.
[0025] Legs 21 B- 21 F, similar to the leg 20 A, are connected to the side 24 . The legs 21 A- 21 F have equal spacing therebetween.
[0026] Because of the legs 21 A- 21 F, the bottom 18 does not usually rest upon the ground. Therefore, when a motor vehicle drives over the hazard marker 10 on an asphalt roadway, the V shaped feet sink into the asphalt thereby preventing the hazard marker 10 from being moved laterally. Additionally, when the motor vehicle drives over the hazard marker 10 , the ramp edges of the legs 20 A- 20 F prevent damage to the motor vehicle and to the hazard marker 10 .
[0027] As shown in FIGS. 3 and 4, rechargeable nicad batteries 26 - 30 are connected in series. More particularly, the battery 26 is connected to the battery 27 through a conductive ribbon 32 and the battery 27 is connected to the battery 28 through a conductive ribbon 34 . Similarly, the battery 26 is connected to the battery 30 through a conductive ribbon 36 and the battery 30 is connected to the battery 29 through a conductive ribbon 38 . In an alternative embodiment, non-rechargeable batteries are used An anode (not shown) of the battery 28 and a cathode (not shown) of the battery 29 are connected through wires 40 , 42 , respectively, to a plug 44 which mates with a socket 46 . A pair of wires 50 connects the socket 46 to the circuit board 19 , whereby the batteries 26 - 30 provide a voltage to the circuit board 19 . The plug 44 and the socket 46 render unnecessary a making and breaking solder connections when the batteries 26 - 30 are removed and reinstalled for any purpose.
[0028] The lower housing 12 includes similar posts 54 - 58 (FIG. 4) that extend perpendicularly from the bottom 18 . When the lower housing 12 and the upper housing 14 are connected together, the posts 54 - 58 wedge the batteries 26 - 30 , respectively, against the side 24 . Because the hazard marker 10 has the shape of the disc, a curvature of the side 24 and the posts 54 - 58 maintain positions of the batteries 26 - 30 within the lower housing 12 .
[0029] It should be understood that the batteries 26 - 30 rest upon the bottom 18 . Additionally, a sponge rubber annulus 60 is placed over the batteries 26 - 30 . The circuit board 19 is placed upon the sponge annulus 60 . Because of a thickness of the annulus 60 , the circuit board 19 is within the upper housing 14 .
[0030] As shown in FIG. 5, LEDs 20 -A, 20 -J have spring-like leads that are connected to the circuit board 19 . An interior surface 60 of the upper housing 14 urges the LED 20 -A into a position that causes an angle 62 to be sustained between a central axis 64 of the LED 20 -A and a surface 14 L of the lower housing 14 . It has been determined that when the angle 62 is substantially equal to four degrees, light transmitted through the wall 14 V is visible at distances in excess of fifty yards. The LED 20 -J is positioned in a similar manner. In this embodiment, the positioning of the LEDs 20 -A, 20 -J is exemplary of the positioning of the LEDs 20 -B through 20 -I and LEDs 20 -K through 20 -T.
[0031] The upper housing 14 has annular depressions 66 therein that diffuses light from the LEDs 20 -A through 20 -T that passes therethrough. The diffused light does not cause a glare that temporarily blinds a passing motorist.
[0032] In an alternative embodiment, the LEDs 20 -A through 20 -T are positioned to transmit light vertically through a horizontal wall 14 A of the upper housing 14 . The vertically transmitted light is used to indicate a scene of a mishap to an aircraft.
[0033] At the center of the interior of the housing 12 (FIG. 4) is a post 68 with an axial hole 70 therethrough. The hole 70 includes slots 72 , 74 that extend through the column 68 . A storage hole 76 (FIGS. 1 and 2) similar to and coaxial with the hole 70 extends through the upper housing 14 .
[0034] The circuit board 19 (FIG. 3) has a central hole 77 therethrough. Spring contacts 78 , 80 are connected to the circuit board 19 near the hole 77 . When the housings 12 , 14 are connected, the contacts 78 , 80 are fitted into the slots 72 , 74 , respectively. The contacts 78 , 80 are connected to the batteries 26 - 30 via a bridge rectifier (not shown) on the circuit board 19 . Because of the bridge rectifier, polarity of a voltage applied to the contacts 78 , 80 is irrelevant.
[0035] As shown in FIG. 6, a storage stand is for storing the hazard marker 10 and hazard markers 10 A, 10 B that are similar to the hazard marker 10 . The storage stand includes a fiber glass charging stick 82 that has a rectangular cross section. Metal strips 84 extend along opposite sides of the stick 82 . An end (not shown) of the stick 82 is connected to a base 86 that has an outward appearance similar to that of the hazard marker 10 . It should be understood that the appearance of the base 86 is of no critical importance.
[0036] As explained hereinafter, when the hazard marker 10 is positioned upside down (with the upper housing 14 below the lower housing 12 ), the batteries 26 - 30 do not provide power. Accordingly, the hazard marker 10 is stored upside down with the stick 82 passing through the holes 70 , 76 , 77 . The hazard markers 10 A, 10 B are similarly stored. Within the hole 70 , the contacts 78 , 80 (FIG. 3) provide a connection to the metal strips 84 , thereby providing an electrical connection of the metal strips 84 to the batteries 26 - 30 via the bridge rectifier. A similar electrical connection is made to the hazard markers 10 A, 10 B.
[0037] A pair of wires 88 passes through an outer wall 90 of the base 86 to connect to the metal strips 84 . Because of the electrical connection of the metal strips 84 to the batteries 26 - 30 , application of a charging voltage to the wires 88 charges the batteries 26 - 30 . Batteries of the hazard markers 10 A, 10 B are similarly charged.
[0038] As shown in FIG. 7, there is a connection (not shown) between the batteries 26 - 30 and a mercury switch 92 . When the hazard marker 10 is right side up, the switch 92 closes, thereby providing a voltage, designated as Vcc, to a contact 92 A of the switch 92 . The contact 92 A is connected to an operational amplifier 94 and an oscillator 96 , whereby the voltage, Vcc, is provided to the operational amplifier 94 and the oscillator 96 .
[0039] The oscillator 96 provides a train of pulses with an 18 millisecond period that are represented in FIG. 8( a ). The oscillator 96 is connected to a ring counter 98 at a clock input 100 .
[0040] A first pulse 101 A and a second pulse 102 A of the train of pulses (FIG. 8( a )) cause an output 101 of the ring counter 98 to provide an 18 millisecond pulse 101 B (FIG. 8( b )). The second pulse 102 A and a third pulse 103 A (FIG. 8( a )) cause an output 102 of the ring counter 98 to provide an 18 millisecond pulse 102 B, FIG. 8( c ). It should be understood that the pulse 101 B ends simultaneously with a beginning of the pulse 102 B. In a similar manner, 18 millisecond pulses are provided at outputs 103 - 110 , respectively, of the ring counter 98 . The pulses at the outputs 103 - 110 are represented in FIG. 8( d )-FIG. 8( f ) as pulses 103 B- 110 B, respectively.
[0041] From the explanation given hereinbefore the pulses 101 B- 110 B are provided in a serial manner, one at a time. It should be understood that the amplitude of the pulses 101 B- 110 B is directly related to a voltage applied to an excitation input of the ring counter 98 . The application of the voltage to the excitation input is described hereinafter.
[0042] The outputs 101 - 110 are connected to bases of NPN transistors 112 - 121 , respectively. The transistors 112 - 121 have their collectors respectively connected to LEDs 20 -A, 20 -C, 20 -E, 20 -G, 20 -I, 20 -K, 20 -M, 20 -O, 20 -Q and 20 -S at their cathodes, anodes thereof being all connected to the contact 92 A. The transistors 112 - 121 have their emitters respectively connected to the LEDs 20 -B, 20 -D, 20 -F, 20 -H, 20 -J, 20 -L, 20 -N, 20 -P, 20 -R, 20 -T at their anodes, cathodes thereof being all connected through a sampling resistor 122 to ground and to the operational amplifier 94 at an inverting input thereof, whereby a sampled voltage is provided to the amplifier 94 .
[0043] When the switch 92 is closed, substantially equal currents flow through the LEDs 20 -A, 20 B in response to the pulse 101 B (FIG. 8) being provided to the transistor 112 , thereby causing an emission of light from the LEDs 20 A, 20 B. In a similar manner, current flows through the LEDs 20 -C, 20 -D, the LEDs 20 -E, 20 -F, the LEDs 20 -G, 20 -H, the LEDs 20 -I, 20 -J, the LEDs 20 -K, 20 -L, the LEDs 20 -M, 20 -N, the LEDs 20 -O, 20 -P, the LEDs 20 -Q, 20 -R and the LEDs 20 -S, 20 -T in response to the pulses 102 B- 110 B, respectively, to cause emissions of light therefrom.
[0044] The contact 92 A is connected through a resistor 124 to a non-inverting input of the amplifier 94 . A resistor 126 is connected from the non-inverting input to ground. In other words, the resistors 124 , 126 are a voltage divider that provides a reference voltage to the non-inverting input. An output of the amplifier 94 is connected to an excitation input 128 of the ring counter 98 whereby an excitation input voltage is provided to the ring counter 98 .
[0045] When, for example, the pulse 101 B is provided, an emitter current of the transistor 112 passes through the resistor 122 , thereby providing the sampled voltage. In response to the sampled voltage being greater than the reference voltage, the excitation input voltage is reduced, thereby reducing the amplitude of the pulse 101 B (FIG. 8) to cause a reduction of the emitter current of the transistor 112 . Correspondingly, in response to the sampled voltage being less than the reference voltage, the excitation input voltage is increased, thereby increasing the amplitude of the pulse 101 B, to cause an increase of the transistor 112 emitter current, whereby the amplitude of the pulse 101 B is regulated. In a similar manner, the amplitudes of the pulses 102 B- 110 B are regulated.
[0046] In an alternative embodiment, the diodes 20 -A, 20 -C, 20 -E, 20 -G, 20 -I, 20 -K, 20 -M, 20 -O, 20 -Q, and 20 -S are omitted and the collectors of transistors 112 - 121 are connected to the contact 92 A.
[0047] Thus there is described herein a turbo flare hazard marker that is especially suited for marking a problem area created by a mishap on a highway. | A highway hazard marker is housed within a disc shaped high impact plastic housing, an upper portion of which is transparent. A plurality of LEDs are circularly disposed proximal to the side of the upper portion. A ring counter provides signals to transistors that sequentially drive the LEDs. Excitation provided to the ring counter is controlled to cause a desired current through the LEDs. | 8 |
FIELD OF THE INVENTION
The present invention relates generally to a closet shelf apparatus and, more particularly, to said apparatus comprising two (2) cable drive mechanisms that allow the shelf to be pulled out and down for ease of access.
BACKGROUND OF THE INVENTION
People with physical challenges including, such as the elderly, the handicapped, people of short stature, wheelchaired individuals and those recovering from injuries or surgery know the difficulties encountered when accessing articles on a closet shelf of some height, especially a shelf situated above a clothing rod. Many of the aforementioned people find it difficult to reach important items on the shelves. For those confined to a wheelchair, obtaining anything off of a closet shelf becomes a virtually impossible task. Accordingly, there exists a need for a means by which physically challenged individuals, can be afforded the ability to access the contents of a closet. The development of the invention herein disclosed fulfills this need.
The invention is an apparatus that utilizes a novel pull-out, drop-down, spring-loaded closet storage shelf system. Although resembling a conventional closet storage shelf, the innovative system and apparatus provides for two (2) cable drive mechanisms and a plurality of supports that allows the shelf and an attached rod to pull out and down from a conventional stowed position. In the lowered position, access is comfortable for someone sitting in a wheelchair, for a child, or for someone unable to reach the shelf and/or the rod without assistance. A plurality of support rods and braces provide safe support for even the heaviest of loads. When shelf access is complete, a cable return mechanism allows the shelf to be simply returned back up to its original position.
Several attempts have been made in the past to provide systems for retractable storage units. U.S. Pat. No. 5,203,619, issued in the name of Welsch et al., describes a vertical retractable ceiling storage system comprising a frame and a retractable vertical lifting mechanism. However, unlike the present invention, the Welsch storage system is intended as a ceiling support structure which is retracted within and hidden behind the ceiling panel, thereby posing increased difficulties in retrofitting the system; additionally the system only provides vertical positioning to create increased floor space.
U.S. Pat. No. 5,211,461, issued in the name of Teufel et al., describes vertical adjustable extension drawers comprising two (2) adjustable extension rails, a plurality of horizontally-extending guide ribs for drawers, and a guide arm which mounts to a vertical surface. However, unlike the present invention, the Teufel drawers provides for a customizable drawer system with an extendable rail system for use with an outer housing which enables small vertical adjustments of the drawers.
U.S. Pat. No. 5,605,238, issued in the name of Jacobs, describes a shelving system comprising a plurality of support structures, shelf planks, fastening brackets, and fasteners which are mounted to a vertical wall surface and provides a modular and adjustable shelving system for closets. However, unlike the present invention, the Jacobs shelving system is merely a closet organizer and lacks the benefit of adjustable shelving space for the physically challenged.
U.S. Pat. No. 6,241,048, issued in the name of Heilmann, describes a storage and lift platform comprising a plurality of platforms, cables, frame members, and a drive axle which provides a means of vertically raising and lowering a single or plurality of platforms for long-term storage. However, unlike the present invention, the Heilmann lift platform only provides vertical adjustments and is intended for larger loads and longer term storage.
U.S. Pat. No. 6,851,376, issued in the name of D'Agostino, discloses a pull down shelf for overhead storage comprising a lower shelf, a pair of scissor-action stabilizers, and wind-up mechanism which enables a user to physically pull a ceiling mounted shelf down to a lower vertical position and then by releasing the wind-up mechanism raising the shelf back to its original position. However, unlike the present invention, the D'Agostino pull down shelf again only provides for vertical position adjustment and lacks the benefit of facilitating to a physically challenged person or a child.
The prior art appears to disclose a variety of retractable storage units. However, none of the prior art particularly describes a motorized shelving unit which provides for both horizontal and vertical position adjustment further providing a means of assisting in the accessing of stored items by a physically challenged person or child. Accordingly, there exists a need for a pull-out, drop-down closet storage system that operates without the disadvantages as described above.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the prior art, it has been observed that there is need for a pull-out, drop-down closet storage system for providing a shelf storage system which assists in the accessing of stowed items by a physically challenged person, an elderly person, or a child.
To achieve the above objectives, it is an object of the present invention to provide a pull-out, drop-down closet storage system comprising a shelf assembly, a horizontal slide assembly, a vertical slide assembly, and a control module.
A further object of the present invention is to provide a shelf assembly comprising a vertical panel and a horizontal panel which form an “L”-shaped structure, a safety lip at the distal end of the horizontal panel, and a first and a second brace which provide a connection means all of which provide a secure storage shelf surface for a user to store items on.
Yet still another object of the present invention is to provide a horizontal slide assembly comprising a set of horizontal frames, a first cable drive mechanism, a wall mounting plate, a first set of rollers, and a horizontal roller channel.
Yet still another object of the present invention is to provide a wall mounting plate which provides a surface for attaching the system to a wall and a first and a second horizontal frame which attach to the mounting plate parallel to one another and to the floor and extend out perpendicularly from the wall surface.
Yet still another object of the present invention is to provide a first set of rollers which provide horizontal movement of the vertical slide assembly between the horizontal frames via a horizontal roller channel located on the inside of the horizontal frames which provide a linear guide to the horizontal rollers.
Yet still another object of the present invention is to provide a first cable drive mechanism comprising a first motor attached to the first horizontal frame which provides the means of horizontal linear movement to the vertical slide assembly via mechanical interaction between the motor and a horizontal cable, a first drive pulley and a plurality of horizontal idler pulleys.
Yet still another object of the present invention is to provide a vertical slide assembly comprising a set of vertical frames, a second cable drive mechanism, a second set of rollers, and a vertical roller channel.
Yet still another object of the present invention is to provide a second set of rollers which provide vertical movement of the shelf assembly between the vertical frames via a vertical roller channel located on the inside of the vertical frames which provide a linear guide to the vertical rollers.
Yet still another object of the present invention is to provide a second cable drive mechanism comprising a second motor attached to the inner surface of the first vertical frame which provides the means of vertical linear movement to the shelf assembly via mechanical interaction between the motor and a vertical cable, a second drive pulley and a plurality of vertical idler pulleys.
Yet still another object of the present invention is to provide a first support leg and a second support leg each comprising a first foot portion and a second foot portion respectively which provide a means of attaching the system to the floor and providing a means of supporting the combined weight of the system and any stowed load.
Yet still another object of the present invention is to provide a control module comprising software logic functions and radio frequency (RF) reception and processing which provides intelligent motion control and electrical power distribution to the horizontal and vertical slide assemblies.
Yet still another object of the present invention is to provide a first and a second horizontal position switch located on opposite ends of the horizontal roller channel and provides horizontal position information of the vertical slide assembly to the control module.
Yet still another object of the present invention is to provide a first and a second vertical position switch located on opposite ends of the vertical roller channel and provides vertical position information of the shelf assembly to the control module.
Yet still another object of the present invention is to provide a wall mounted system activation switch which communicates with the control module and initiates the deployment of the system and the return to the stowed position.
Yet still another object of the present invention is to provide a portable remote control system activation switch which communicates with the control module via an RF signal and initiates the deployment of the system and the return to the stowed position.
Yet still another object of the present invention is to provide a shelf storage system comprising a normal stowed position and a deployed position which repositions the shelf assembly approximately sixteen (16) inches away from a wall surface in the horizontal direction and approximately thirty (30) inches in a vertical direction.
Yet still another object of the present invention is to provide a method for utilizing a pull-out, drop-down closet storage system.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which:
FIG. 1 is a front view of a pull-out, drop-down closet storage system 10 in an upward or stowed orientation installed therein a conventional closet, according to the preferred embodiment of the present invention;
FIG. 2 is a side view of a pull-out, drop-down closet storage system 10 in the upward or stowed orientation, according to a preferred embodiment of the present invention;
FIG. 3 is a side view of a pull-out, drop-down closet storage system 10 in a lowered access orientation, according to a preferred embodiment of the present invention;
FIG. 4 is a section view taken along section A-A (see FIG. 1 ) depicting cable drive portions of a pull-out, drop-down closet storage system 10 , according to a preferred embodiment of the present invention; and,
FIG. 5 is an electrical block diagram of a pull-out, drop-down closet storage system 10 , according to a preferred embodiment of the present invention.
DESCRIPTIVE KEY
10
pull-out, drop-down closet storage system
20
horizontal slide assembly
21
first horizontal frame
22
second horizontal frame
23
wall mounting plate
24
horizontal roller channel
25
horizontal cable
26
idler pulley
27
horizontal cable attachment
28
first motor
29
first drive pulley
30
horizontal position switch
31
vertical position switch
40
vertical slide assembly
41
first vertical frame
42
second vertical frame
43
crossmember
44
vertical roller channel
45
roller
46
vertical cable attachment
47
vertical cable
48
second motor
49
second drive pulley
60
shelf assembly
61
shelf
62
vertical panel
64
shelf attachment bracket
65
brace
66
lip
69
first support leg
70
second support leg
71
first support foot
72
second support foot
100
wall surface
105
fastener
110
floor surface
120
clothes
130
load/stored item
150
control module
155
110-volt power source
160
wiring
165
wall mounted switch
180
remote controller
181
radio frequency (RF) signal
182
antenna
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The best mode for carrying out the invention is presented in terms of its preferred embodiment, herein depicted within FIGS. 1 through 5 . However, the invention is not limited to the described embodiment and a person skilled in the art will appreciate that many other embodiments of the invention are possible without deviating from the basic concept of the invention, and that any such work around will also fall under scope of this invention. It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope.
The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items.
The present invention describes a pull-out, drop-down closet storage system (herein described as the “system”) 10 and associated method of use, comprising a motorized means of lowering a closet shelf 61 therefrom a conventional upper location above hung clothing 120 , thereto an easily accessed lower position activated by a wall mounted switch 165 or a hand-held remote controller 180 . The system 10 utilizes two (2) cable drive mechanisms to smoothly extend and lower a loaded shelf 61 to a convenient height approximately thirty (30) inches above a floor surface 110 . In the lowered position, access is comfortable for a seated user, someone sitting in a wheelchair, a child, or for someone unable to reach a high shelf without assistance.
Referring now to FIG. 1 , a front view of the system 10 in the upward or stowed orientation installed therein a conventional closet, according to the preferred embodiment of the present invention, is disclosed. The system 10 comprises a horizontal slide assembly 20 , a vertical slide assembly 40 , a shelf assembly 60 , a first support leg 69 , a second support leg 70 , and a control module 150 . The system 10 is illustrated here installed therein a normal or walk-in closet being affixed thereto at an upper distal wall surface 100 and a proximal floor surface 110 , thereby providing a rigid faming means thereto the system 10 . The system 10 provides automatic positioning of a shelf 61 using side mounted motorized horizontal and vertical motion devices to conveniently present said shelf 61 thereto a user.
The horizontal slide assembly 20 provides an initial transportation of a loaded shelf 61 in a horizontal direction away from the wall surface 100 thereto a position forward of any existing shelves, hanging rods, and clothing 120 . The vertical slide assembly 40 then provides a secondary vertical motion to lower said shelf 61 thereto a convenient access height (see FIGS. 2 and 3 ). The horizontal slide assembly 20 provides an attachment and motorized transport means thereto affixed vertical slide 40 and shelf 60 assembly portions by propelling said assemblies 40 , 60 therefrom an upper distal position to an upward proximal position. The horizontal slide assembly 20 comprises a rugged structure being capable of supporting a weight of the attached assemblies 40 , 60 as well as an expected load 130 of fifty (50) pounds thereupon the shelf assembly 60 . The horizontal slide assembly 20 provides a “U”-shaped structure being formed or welded and further comprising a first horizontal frame 21 , a second horizontal frame 22 , and a wall mounting plate 23 . The mounting plate 23 and horizontal frame portions 21 , 22 preferably comprise heavy-duty extruded or stamped steel members. The wall mounting plate 23 a width of the system 10 being approximately six (6) to eight (8) inches high providing an attachment means thereto the wall surface 100 using a plurality of common fasteners 105 such as wall anchors, lag screws, or the like being securely mounted to wooden framing members within the wall surface 100 . The wall mounting plate 23 provides a formed or welded attachment thereto the horizontal frame portions 21 , 22 which extend perpendicularly therefrom, being arranged in a parallel fashion thereto one another and parallel to a closet floor surface 110 . The horizontal frame portions 21 , 22 provide a guided transport thereto affixed vertical slide 40 and shelf 60 assemblies using respective pairs of rollers 45 supporting a central load 130 in a parallel manner. The horizontal frame portions 21 , 22 provide a parallel load bearing function envisioned being similar thereto common drawer roller-slide hardware. The horizontal slide assembly 20 comprises a single-sided horizontal cable 25 (see FIG. 4 ) driven means via a motor 28 and associated drive components affixed thereto an inner surface of the first horizontal frame portion 21 while the second horizontal frame 22 provides a non-motorized guiding means thereto the horizontal slide assembly 20 when in motion. The rollers 45 and cable drive portions 25 of the horizontal slide assembly 20 provide an attachment means thereto the vertical slide assembly 40 . The horizontal slide assembly 20 provides an attachment means thereto a first vertical support leg 69 and a second support leg 70 affixed along outward surfaces of the first 21 and second 22 horizontal frame portions using common fasteners 105 and located approximately two (2) feet from the wall surface 100 extending vertically downward to a floor surface 110 . The support legs 69 , 70 preferably comprise sturdy rectangular tubing capable of supporting a combined weight of the system 10 and an applied load 130 placed thereupon when in use. The legs 69 , 70 further comprise a first foot portion 71 and a second foot portion 72 comprising welded or fastened rectangular structures extending along the floor surface 110 therefrom said legs 69 , 70 in a perpendicular fashion being approximately three (3) inches square being affixed thereto said floor surface 110 using common fasteners 105 .
The vertical slide assembly 40 further comprises a first vertical frame 41 , a second vertical frame 42 , and a crossmember 43 . The vertical slide assembly 40 extends downwardly therefrom the horizontal slide assembly 20 providing a vertical transport means thereto the affixed shelf assembly 60 . The vertical slide assembly 40 provides a roller 45 guided, single-sided motor 48 driven assembly in a similar fashion as the aforementioned horizontal slide assembly 20 using similar materials and methods of construction. The crossmember 43 provides a lateral strengthening and stiffening means therebetween the first vertical frame 41 and second vertical frame portions 42 . The crossmember 43 comprises a rectangular structural member extending therebetween said first vertical frame 41 and second vertical frame 42 along a rearward vertical edge being fastened thereto using a welding process or common fasteners 105 . The shelf assembly 60 provides a stable horizontal surface on which a user may store garments, clothing, shoes, or other personal stored items 130 in an expected manner. The shelf assembly 60 is illustrated here being in a retracted and stowed state directly above an existing closet shelf; however, it is understood that the shelf assembly 60 may be installed in such a way as to replace all or a section of said existing closet shelf with equal benefit.
The control module 150 is located centrally along a front surface of the wall mounting plate 23 comprising a rectangular plastic housing providing a protective enclosure thereto internal electrical and electronic equipment (see FIG. 5 ).
The horizontal 20 and vertical 40 slide assembly portions of the system 10 are envisioned being preferably made using extruded or stamped steel members; however other materials may be provided such as plastics, aluminum, synthetic material, and/or any other sturdy lightweight materials.
The system 10 is envisioned being utilized therein closet areas but may also be utilized to allow items to be stored within an inside room of households, hotels, schools, hospitals, industrial areas and the like. Further, the system 10 may be utilized using an attachment thereto overhead joists of a closet, basement, garage, and/or other areas which have limited or inaccessible spaces.
Referring now to FIGS. 2 and 3 , side views of the system 10 depicting stowed and lowered access orientations, according to a preferred embodiment of the present invention, is disclosed. The system 10 comprises a first horizontal frame 21 , a first vertical frame 41 , and a shelf 61 . During use, an operator activates the system 10 via a wall mounted switch 165 , or via a remote control 180 , which in turn begins a sequential motion, thereby repositioning the shelf 61 from a stowed orientation (see FIG. 2 ) thereto an extended and lowered access orientation (see FIG. 3 ). An initial horizontal motion moves the shelf 61 forward approximately sixteen (16) inches being powered by a first motor 28 . Subsequently, a downward vertical movement powered by a second motor 48 positions said shelf 61 approximately thirty (30) inches above a floor surface 110 as shown in FIG. 3 , thereby allowing easy access thereto a contained load 130 by a child or seated adult.
FIG. 4 is a section view taken along section A-A (see FIG. 1 ) depicting cable drive portions of the system 10 , according to the preferred embodiment of the present invention, is disclosed. The system 10 is illustrated here showing a single motorized side only for clarity. The system 10 comprises a first horizontal frame 21 and a first vertical frame 41 being designed to work in conjunction therewith the corresponding non-driven mirror-image second horizontal frame 22 and second vertical frame 41 portions, respectively, being located along an opposing side of the system 10 (see FIG. 1 ).
The first horizontal frame 21 further comprises a horizontal roller channel 24 , a horizontal cable 25 , a plurality of idler pulleys 26 , a horizontal cable attachment 27 , a first motor 28 , a first drive pulley 29 , and a pair of horizontal position switches 30 . The horizontal roller channel 24 provides a captivating linear guide thereto a pair of rollers 45 being arranged approximately four (4) inches apart. The rollers 45 provide a guided attachment therebetween the first horizontal frame 21 and the first vertical frame 41 . The rollers 45 comprise common ball-bearing roller devices approximately one (1) to two (2) inch in diameter with integral threaded axles, each being threadingly affixed thereto the first vertical frame 41 via drilled holes and common fasteners 105 . The horizontal roller channel 24 also comprises a pair of horizontal position switches 30 being located thereat each extreme end portion. The horizontal position switches 30 provide information thereto the control module 150 pertaining to a position of the first vertical frame 41 during deployment or stowage of the system 10 . The horizontal position switches 30 are located exclusively thereupon the motor driven first horizontal frame 21 . The horizontal position switches 30 preferably comprise lever type micro-switches being common in the industry. The first motor 28 comprises a common sealed 110-volt AC reversing motor with integral gear reduction and single output shaft being similar to those found in common drill motors. The first motor 28 provides a two-directional drive means thereto the cable 25 via a first drive pulley 29 mounted thereto the output shaft portion of the motor 28 . The cable 25 provides a driving attachment means therebetween the first horizontal frame 21 and the first vertical frame 41 . The cable 25 comprises a length of common stainless steel wire rope forming a continuous loop having a lower taught length positioned parallel thereto the aforementioned horizontal roller channel 24 . The cable 25 is envisioned being a durable braided wire rope preferably, but not essentially comprising a plastic friction sleeve and having a diameter of approximately one-sixteenth ( 1/16) to one-eighth (⅛) inch. The cable loop 25 is routed therearound a plurality of free-spinning idler pulleys 26 providing a positioning and tensioning means thereto. The cable 25 provides transmission of a linear force thereto the first vertical frame 41 via a horizontal cable attachment 27 . The horizontal cable attachment 27 comprises preferably, but not essentially a common cable holding bolt device similar to those used on bicycle braking systems.
The rollers 45 and the horizontal cable attachment 27 provide a means of guided and driven attachment therebetween the first horizontal frame 21 and the first vertical frame 41 . The first vertical frame 41 is in mechanical cooperation therewith the shelf assembly 60 in a similar manner as the aforementioned first horizontal frame 21 and first vertical frame 41 . The first vertical frame 41 provides a vertical guiding and driving means thereto the shelf assembly 60 comprising a vertical roller channel 44 , a pair of vertical position switches 31 , a vertical cable attachment 46 , a vertical cable 47 , a second motor 48 , a plurality of idler pulleys 26 , and a second drive pulley 49 . Attachment therebetween the first vertical frame 41 and the shelf assembly 60 is accomplished by the second cable attachment 46 and a pair of rollers 45 as shown. The rollers 45 are arranged approximately four (4) inches apart being captivated therein the vertical roller channel 44 , thereby providing secure vertical travel of the shelf assembly 60 regardless of offset forces resulting from a load 130 applied thereto the shelf 61 . The second cable attachment 46 provides an attachment means thereto a shelf attachment bracket portion 64 of the shelf assembly 60 in a similar manner as the aforementioned horizontal cable attachment 27 .
The shelf assembly 60 further comprises a shelf 61 , a vertical panel 62 , a pair of braces 65 (only one shown here), and a safety lip 66 . The shelf assembly 60 is envisioned being made of sturdy wood or metal components capable of supporting a load of fifty (50) pounds being applied thereto the shelf portion 61 . The shelf attachment bracket 64 comprises a “T”-shaped stamped or machined metal fixture being mounted securely thereto a forward surface of the vertical panel 62 along opposite side edges using common fasteners 105 . The shelf assembly 60 provides a storage surface thereto a load 130 comprising shoes, boxes, personal items, and the like. The shelf 61 and vertical panel 62 comprise rectangular flat panels approximately one (1) inch thick being joined along a rear lower edge forming an “L”-shaped structure. The shelf 61 also comprises a safety lip 66 approximately one (1) inch high extending across a forward edge region to avoid possible shifting of said load 130 therefrom the shelf 61 during movement. The braces 65 provide a common angular connection therebetween the shelf 61 and vertical panel 62 being in a state of tension and providing a strengthening means thereto the shelf assembly 60 . The shelf assembly 60 is assembled using common fasteners 105 such as screws, bolts, or the like.
Referring now to FIG. 5 , an electrical block diagram of the system 10 , according to the preferred embodiment of the present invention, is disclosed. The system 10 comprises a control module 150 , a pair of horizontal position switches 30 , a pair of vertical position switches 31 , a first motor 28 , a second motor 48 , a wall-mounted switch 165 , a remote controller 180 , an antenna 182 , and interconnecting wiring 160 . Electrical power is provided thereto the system 10 via a 110-volt power source 155 is hard-wired thereto the control module 150 . The control module 150 provides intelligent motion control, electrical power distribution, radio frequency (RF) signal reception/processing, and software logic functions thereto the system 10 . The control module 150 comprises a rectangular plastic housing providing a protective enclosure thereto internal electrical and electronic components and equipment such as circuit boards, relays, microprocessors, embedded software, an RF receiver, and the like. The control module 150 receives and processes commands therefrom the wall mounted switch 165 and the remote controller 180 to initiate upward and downward movements of the shelf assembly 60 . The wall mounted switch 165 comprises a common self-contained panel-mounted device with included three (3) position rocker-type switch having a spring return center position. The remote controller 180 is envisioned being similar to common hand-held garage door opener units providing standard features such as a rectangular plastic housing, a battery compartment, batteries, an RF transmitter, and “UP” and “DOWN” digit operated buttons. The control module 150 further comprises a top mounted RF antenna 182 for receiving RF signals 181 emitted therefrom the remote controller 180 . The control module 150 provides logic processing of received signals via embedded software and in turn energizes internal relays in a conventional manner, thereby sequentially directing a current thereto the first motor 28 and second motor 48 resulting in horizontal and vertical motions of the slide assemblies 20 , 40 , respectively. Motion control signals are also conducted thereto the control module 150 via common copper conductors 160 therefrom the position switches 30 , 31 which detect a travel limit for the horizontal 20 and vertical 40 slide assemblies, respectively. Upon obtaining a travel limit signal therefrom a position switch 30 , the control module 150 halts an appropriate motor 28 , 48 , thereby preventing over-current damage from occurring.
In operation, a user presses either an “UP” or “DOWN” button portion of the wall-mounted switch 165 or remote controller 180 ; a continuous current is then conducted thereto the motors 28 , 48 in a sequential fashion; an input signal is conducted therefrom a position switch 30 , 31 indicating that a limit of travel has occurred and an appropriate motor 28 , 48 is halted; the user releases the “UP” or “DOWN” button portion of the wall-mounted switch 165 or remote controller 180 , thereby halting the system 10 in its current position.
It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope.
The preferred embodiment of the present invention can be utilized by the common user in a simple and effortless manner with little or no training. After initial purchase or acquisition of the system 10 , it would be installed as indicated in FIG. 1 and utilized as indicated in FIGS. 2 and 3 .
The method of installing and utilizing the system 10 may be achieved by performing the following steps: assembling the horizontal and vertical slide assemblies 20 , 40 into a single unit, if not previously assembled; assembling the shelf assembly 60 thereto the vertical slide assembly 40 using provided common fasteners 105 , if not previously assembled; assembling the first 69 and second 70 support legs thereto the first 21 and second 22 horizontal frames such that the first 71 and second 72 support feet rest thereupon a floor surface 110 ; fastening the system 10 to a rearward wall surface 100 using provided fasteners 105 ; fastening the system 10 to a floor surface 110 using provided fasteners 105 ; installing a fresh set of batteries therewithin the remote controller 180 ; installing the wall-mounted switch 165 along a wall surface 100 at a safe distance therefrom the system 10 ; routing wiring 160 within a wall 100 or discreetly along exterior surfaces of said wall 100 thereto the wall-mounted switch 165 ; connecting an existing 110-volt power source 155 thereto the control module 150 ; energizing the 110-volt power source 155 ; moving the shelf assembly 60 thereto the access position by pressing and holding the “DOWN” button on either the remote controller 180 or the wall-mounted switch 165 until a forward horizontal position switch 30 and subsequent lower vertical position switch 31 is activated causing a motion of the shelf 61 to cease in an access orientation; placing a load 130 of personal items such as shoes, boxes, or the like thereupon the shelf 61 as desired; pressing and holding the “UP” button either on the remote controller 180 or the wall-mounted switch 165 until an upper vertical position switch 31 is activated and a vertical motion ceases; allowing the shelf assembly 60 to proceed in a rearward direction until a rearward horizontal switch 30 is activated and motion ceases; releasing said “UP” button; and benefiting from increased safety, improved access, and effortless storage of personal items 130 using the present invention 10 .
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention and method of use to the precise forms disclosed. Obviously many modifications and variations are possible in light of the above teaching. The embodiment was chosen and described in order to best explain the principles of the invention and its practical application, and to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions or substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but is intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention. | A motorized pull-out, drop-down, closet storage shelf system is herein disclosed. The shelf system provides a track system and a series of roller slides which propel a shelf forward and downward from its conventional stowed position to a lowered position by simply pressing a button. The access position allows comfortable access for someone sitting in a wheelchair, for a child, or for someone unable to reach the shelf without assistance. The shelf system is capable of transporting heavy loads of up to fifty (50) pounds. When shelf access is complete, the motorized mechanism returns the shelf to its original position. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to a fused solid electrolytic capacitor, and more particulary to a fusing arrangement of a chip type solid electrolytic capacitor.
Chip type solid electrolytic capacitors are used widely in various electronic circuits. It has a fault rate which is small. The fault thereof, if it occurs, is often in a mode of a short circuit. When the short circuit happens, a large short-circuit current flows to heat the capacitor element and sometimes to burn the capacitor element. For protecting other circuit components from this excessive short-circuit current, a fuse is incorporated into a solid electrolytic capacitor. As for prior art, there is such a solid electrolytic capacitor with a fuse incorporated therein as disclosed in U.S. Pat. No. 4,107,762 issued on Aug. 15, 1978.
The fusing arrangement in this prior art has a fundamental structure wherein one end of an external cathode lead is fixed by an adhesive insulating resin to a cathode layer on a side surface of a capacitor element. The resin adhesive insulates the cathode lead from the cathode layer of the capacitor element. One end of a fuse wire is connected to one end of a cathode lead, and the other end of the fuse wire is connected to the cathode layer on the side surface of the capacitor element. In such a fusing arrangement, there is the possibility that, in a process for fixing the external cathode lead against this adhesive resin layer and hardening the adhesive resin, a part of the cathode lead may pierce through the adhesive resin layer to make contact with the cathode layer.
To avoid such a possibility of a short-circuit, the thickness of the adhesive resin layer should be made large enough, e.g., 1 mm or more. However, conponents used in a chip type solid electrolytic capacitor must be very small in size in order to provide for miniaturization. For instance, the thickness of external leads is about 0.5 mm and the diameter of a fuse element is about 50 μm to 100 μm. Therefore, the adhesive resin layer having a thickness of 1 mm or more is an obstacle to prevent further reduction of the total size of the fused solid electrolytic capacitor.
Another shortcoming of fusing arrangements in the cited prior art is that the effective length of the fuse element is not constant, because the intermediate portion of the fuse wire may tend to make contact with the cathode layer on the side surface and its contacting portion varies. Furthermore, owing to the above reason, it is difficult to make the effective length of the fuse element long enough.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a fusing arangement which is capable of eliminating the possibility of a short circuit between a cathode external lead and a cathode layer of a capacitor element.
Another object of the present invention is to provide a thin chip type solid electorlytic capacitor incorporating a fusing arrangement adapted of high mass-producting and being easy to assemble.
Still other object of the present invention is to provide a fusing arrangement which is capable of uniformly setting a large effective length of a fuse element.
The present invention is featured in that one end of a cathode external lead, which is to be connected to one end of a fuse element, is located at a position spaced apart from the cathode layer of a capacitor element. The other end of the fuse is connected to the cathode layer covering the capacitor element on its bottom and its side surface between the bottom portion and the top portion. An anode external lead is led out from the top portion of the capacitor element.
According to another feature of the present invention, a fused solid electrolytic capacitor comprises a solid electorlytic capacitor element having a top surface provided with an anode terminal, a bottom surface opposing to the top surface, a side surface extending between the top surface and the bottom surface. A cathode layer is formed on the side surface and the bottom surface. An anode external lead has one end connected to the anode terminal, the other end of the anode external lead being bent into the shape of a letter "U", with arms extending toward the bottom surface. A cathode external lead has one end disposed in a position which is spaced from and opposed to substantially the center of the bottom surface of the capacitor element. The other end of the cathode external lead is bent into the shape of the letter "U", with arms extending toward the top surface. An insulating layer is formed on portions of the side surface and the bottom surface. A fuse element has one end connected to the one end of the U-shaped cathode external lead, the other end the fuse element being connected to the cathode layer provided on the side surface. An elastic resin coats the circumferential surface of the fuse element. An insulating material encapsulates the capacitor element and the elastic resin-coated fuse element.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings, wherein;
FIG. 1 is a sectional view of a first preferred embodiment of a fused chip type solid electrolytic capacitor according to the present invention;
FIG. 2 is a perspective view for describing a fuse-fixing step in a process for manufacturing the chip type solid electrolytic capacitor shown in FIG. 1; and
FIG. 3 is a sectional view of a second embodiment of the fused chip type solid electrolytic capacitor according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, an anode terminal 11 is implanted in a surface of a columnar anode body 1 which is formed by sintering a valve metal powder, such as tantalum powder. The columnar anode body 1 is subjected to anodic oxidation to form an oxide film thereon. A manganese dioxide layer, a carbon layer and a silver paste layer are formed thereon sequentially. As a result, a solid electrolytic capacitor element 10 is formed with a cathode layer 12 in the outer-most layer.
One end of a rectangular-plate-shaped anode external lead 21 is welded to the anode termainal 11. One end of a rectangular-plate-shaped cathode external lead 23 is disposed in a position, which is spaced from the bottom surface of the solid electrolytic capacitor element 10, and is connected to one end of a fuse 31. The other end of the fuse 31 is connected to the cathode layer 12 on the side surface of the capacitor element 10 which is closer to the mounting surface of a chip type capacitor. This is the side which will be mounted on a circuit board. A thin insulating layer 41, such as silicone resin, is formed on a part of the side surface of the capacitor element 10 and on the bottom surface thereof so that an intermediate portion of the fuse 31 does not make contact with the cathode layer 12. The circumferential surface of the fuse 31 is coated with an elastic resin 43.
The assembly is thereafter encapsulated with an electrically insulating material 51, such as epoxy resin, by means of transfer molding, dipping or the like. Then the other end of the anode external lead 21 and the other end of the cathode external lead 23 are bent in to the shape of a letter "U", with the aems of the "U" extending toward the joint portion of the fuse 31 and capacitor element 10.
A preferred example of a method for connecting the fuse wire 31 will be described with reference to FIG. 2. The insulating layer 41 on a part of the side surface and the bottom surface of the capacitor element 10 can be formed easily by immersing a corner portion alone of the capacitor element 10 in a melted insulating, resin such as silicone, with the capacitor element 10 inclined during immersion. One end of the fuse wire 31 is joined to one end of the cathode external lead plate 23 by welding or soldering. The other end of the fuse 31 is then bent toward the capacitor element 10 and connected to the cathode layer 12 on the side surface of the capacitor element 10 by means of a conductive bonding agent 45 or a high temperture solder. The fuse element may consist of a known thin wire, such as one which is obtained by coating an aluminum core with palladium or copper, or by forming a wire from a known solder composed of 93.5% of lead, 5% of tin and 1.5% of silver, or a known solder composed of 97.5% of lead and 2.5% of silver.
The elastic resin suitably used to coat the fuse is a silicone resin. A layer of a silicone resin is formed so as to cover the fuse as a whole or at least the portion thereof which is between the external cathode lead and the bottom section of the capacitor element 10. A silicone resin in which a plurality of bubbles are mixed is perferably used. This enables the fusing characteristics to be further improved. The construction of a fuse thus coated with an elastic resin is explained in detail in U.S. Pat. No. 4,720,772 issued on Jan. 19, 1988.
According to the foregoing embodiment, since the cathode external lead 23 is spaced apart from the bottom surface of the capacitor element 10, there is no possibility of a direct contact to the capacitor element 10. Thus, the yield of the production is improved. Moreover, the total thickness of the chip type capacitor can be minimized, because the conventional thick adhesive resin layer is omitted.
As is clear from FIGS.1 and 2, furthermore, the effective length of the fuse 31 may be made constant and made longer, i.e. it is not shorter than the sum of the distance between the cathode external lead 23 and the bottom surface of the capacitor element 10 and the width of the insulating layer 41 formed on the side surface of the capacitor element 10. Accordingly, this capacitor can, with certainty, be formed so that it has a fuse of an extremely long effective length as compared with a conventional capacitor in which a fuse is connected to the cathode external lead that is fixed on the side surface of the capacitor element 10.
When the effective length of the fuse is too short, it becomes mecessary for the diameter thereof to be reduced to increase the resistance value thereof for the purpose of permitting the fuse to be melted away by a fusing current of a predetermined level. However, if the diameter of the fuse is reduced, it is easily melted during a resin-coating operation, and the productivity yeild decreases. On the other hand, when the fuse structure according to the present invention is employed, the effective length of the fuse can be set extremely long. Then, it becomes unnecessary to reduce the diameter of the fuse, and the productivity yield can be improved. Moreover, since the effective length of the fuse can be set substantially constant, the fusing characteristics of the fuse can be made uniform. The quality of the product can be easily maintained.
An example of dimensions in the embodiment of FIG. 1 will now be given. The anode body of the capacitor element 10 has a corss-sectionally rectangular body, and a thickness of 1.7 mm, a width of 2.6 mm and a length of 2.5 mm with an anode wire of 1.8 mm in length projecting from the anode leading surface. The bottom surface of the capacitor element 10 and nearly a half of the side surface thereof which is on the side opposite the mounting surface are coated with a 0.1-0.2 mm thick insulating resin layer. The distance between the bottom surface of the capacitor element 10 and the external cathode lead 23 is about 0.8 mm. The effective length of the fuse wire 31 under such conditions is about 2.4 mm. When the assembly is encapsulated by the insulating resin, the obtained chip type capacitor has a length of 5.8 mm, a width of 3.2 mm and a thickness of 2.6 mm. The external anode and cathode leads derived from the resin layer are bent into the shape of the letter "U" and set to the length on the mounting surface of 1.3 mm.
In the embodiment of FIGS. 1 and 2, the insulating layer 41 is provided on the entire bottom surface of the capacitor element 10. Even when the insulating layer 41 is removed from the bottom surface, the effective length of the fuse 31 is little influenced. Accordingly, the insulating layer 41 may be limited to a part of the side surface of the capacitor element 10.
In the case where the effective length of the fuse may be sacrificed to a certain extent, the insulating layer 41 need not be formed at all.
An embodiment having no insulating layer will now be described with reference to FIG. 3. The members of this embodiment which are identical with those of the embodiment of FIG. 1 are designated by the same reference numerals and detailed descriptions thereof are omitted.
In the embodiment of FIG. 3, one end of a fuse wire 33 is connected to a cathode layer on a side surface of a capacity 10, which is remote from the mounting surface of the chip type capacitor. The other end of the fuse wire is connected to one end of an exteranl cathode lead 23. The effective length of the fuse 33 is slightly longer than the distance between the bottom surface of the capacitor element 10 and the cathode external lead 23, and is shorter than the fuse in the embodiment of FIG. 1 by a length corresponding to the width of the insulating layer 41.
As shown in FIG. 3, the joint portion of the fuse wire 33 and cathode external lead 23 are positioned on the outer side of the U-shaped lead 23. The joint portion of the fuse 33 and the cathode external lead 23 in the embodiment of FIG. 3 may be positioned on the inner side of the U-shaped cathode external lead 23. The joint portion of the fuse 33 and capacitor element 10 may be positioned on the lower surface of the capacitor element 10, i.e. closer to the mounting surface of the chip type capacitor in the same manner as in the embodiment of FIG. 1.
When a chip type solid electrolytic capacitor is mounted on a circuit board by reflow soldering, the heat is applied thereto from the upper surface thereof in most cases. In order to minimize the possibility that the fuse might be melted or detached from its joint portion while the capacitor is mounted, it is preferable for the fuse to be fixed to the portion closer to the mounting surface of the capacitor as shown in FIG. 1 rather than on the remote surface shown in FIG.3 of the capacitor.
In the above embodiments, the external anode and cathode leads are disposed on the same plane. In order to further increase the effective length of the fuse, it is also possible for the position of the end portion, which is connected to the fuse, of the cathode external lead shown in FIG. 1 to be shifted to a position which is closer to the mounting surface of the chip type capacitor. | A fused solid electrolytic capacitor comprises a six sided body having a pair of spaced parallel sides, one of which will be positioned next to any mounting structure which supports the capacitor. One end of a fuse wire may be connected to either of the spaced parallel sides. The other end of the fuse wire extends through an open passageway in an insulating block to a cathode electrode, thereby giving the fuse wire a fixed length. This way there is no danger that the fuse wire may short circuit along its length to either the capacitor body or the cathode electrode. A result is a smaller capacitor which may be manufactured with a greater harvest yield, as compared to the size and yield of similar prior art fused solid electrolytic capacitors. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a magnetic flux converging type high speed electromagnet of efficient magnetic excitation and shortened response time.
2. Related Art Statement
As is well known, in the conventional electromagnet, the following methods (a ) and (b) are generally adopted for attaining high speed action:
(a) Supplying a large current to an exciting coil for increasing the attracting force of the magnet.
(b) Shortening the response time by increasing the resistance of an exciting coil for reducing the time constant thereof, particularly in a high speed electromagnet utilized for a high speed relay and other applications.
Accordingly, whichever methods (a) and (b) is adopted, it is required to supply a high voltage to the exciting coil.
However, after the attraction has been effected by the electromagnet, the function thereof can be sufficiently maintained even by a small exciting current. Thus, the electric power supplied by a high voltage source for the initial attraction is not needed thereafter and hence is almost entirely wasted.
Moreover, when method (a) is adopted, even if the magnetomotive force is strengthened by supplying a large current to the exciting coil, so as to increase the amount of magnetic flux, the leakage magnetic flux is relatively increased. Consequently, method (a) has an avoidable defect in that the effective magnetic fluxes required for attraction are reduced in response to the increase of leakage magnetic flux.
On the other hand, if method (b) is adopted, the same defect as in the above case cannot be avoided.
SUMMARY OF THE INVENTION
The present invention has been conceived by referring to the above mentioned defects of the conventional technical state.
An object of the present invention is to provide a magnetic flux converging type high speed electromagnet in which the leakage magnetic flux is reduced by the operation of an eddy current, so as to increase the effective magnetic flux and hence reduce the electric power loss. At the same time, a large current is supplied with a comparatively low voltage, particularly in the case of a dc electromagnet, to reduce an equivalent time constant by the operation of an eddy current which is generated only during the attraction in a transient state, so as to facilitate the expectation of the shortened response time.
For attaining the above object, a magnetic flux converging type high speed electromagnet according to the present invention is featured in that plural exciting coil portions, which have individually the same central hollows, are concentrically arranged and inserted in each of the interspaces thereof individually with plural conductor plates each of which has substantially the same central hollow as that of the exciting coil portion and further a radial slit extended from the central hollow to the periphery.
Another magnetic flux converging type high speed electromagnet according to the present invention is featured in that plural exciting coil portions, which have individually the same central hollows, are concentrically arranged in series so as to form an exciting coil assembly and provided in each of interspaces thereof individually and at both ends of the exciting coil assembly with plural conductor plates each of which has substantially the same central hollow as that of the exciting coil portion and further a radial slit extended from the central hollows to the periphery and still further each of which, except one provided on one end of the exciting coil assembly, is provided with a short hollow cylinder having substantially the same inner diameter as that of the central hollow and coaxially extended on one side only by substantially the same length as the thickness of the exciting coil portion, the short hollow cylinder further having a radial slit which is continued with the radial slit formed on the conductor plate.
Still another magnetic flux converting type high speed electromagnet according to the present invention is featured in that the plural conductor plates provided with the short hollow cylinders therebetween are unitarily formed, so as to provide a winding spool for the exciting coil assembly.
Further still another magnetic flux converting type high speed electromagnet according to the present invention is featured in that an assembly of plural exciting coil portions and plural conductor plates, which are alternately arranged in series and individually provided with central hollows continued with each other, is surrounded with plural outer magnetic material frames and a pair of fixed and movable magnetic material cylinders confronting with each other, so as to provide an electromagnetic plunger.
In the magnetic flux converging type high speed electromagnet arranged as mentioned above according to the present invention, the magnetomotive force which is generated by applying ac or dc voltage across the exciting coil induces magnetic fluxes in the magnetic material frame surrounding the exciting coil, and, although these magnetic fluxes induced in the surrounding magnetic material frame were leaked through the exciting coil surrounded by the frame in the conventional arrangement, the leakage of induced magnetic fluxes is prevented by the function of eddy currents induced in the conductor plates individually inserted in the interspaces of the exciting coil portions composing the exciting coil, and, as a result, almost all of the magnetic fluxes induced in the surrounding magnetic material frame is converged in the magnetic material cylinders provided through serially continued central hollows individually formed in the exciting coil portions and the conductor plates inserted in each of interspaces of those coil portions in the axial direction, so as to effectively act as the attracting force.
Particularly in the case that an ac voltage is applied across the exciting coil, eddy currents converged in central portions of the inserted conductor plates are operated as secondary ac currents and hence the input primary ac current increased, and, as a result, the generated attracting force is remarkably increased in comparison with that in the conventional electromagnet applied with the same voltage.
On the other hand, in the case that a dc voltage is applied on the exciting coil, in the transient state in which the current is increased in response to the application of dc voltage and further the movable magnetic material cylinder provided through central hollows of the exciting coil portions and the conductor plates individually inserted therebetween is moved in the axial direction, eddy currents are induced in the conductor plates as if in the same condition as in the case that an ac voltage is applied, so that the input current is increased in response to this condition and, as a result, the attracting force in the initial transient state is increased and hence the electromagnet is operated at a high speed in a manner similar to that which occurs if the time constant is reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
For the better understanding of the invention, reference is made to the accompanying drawings, in which:
FIG. 1 is a crosssectional sideview showing a first embodiment of a plunger type electromagnet according to the present invention;
FIG. 2 is an elevation showing an annular exciting coil in the first embodiment;
FIG. 3 is a crosssectional sideview showing the same annular exciting coil;
FIG. 4 is an elevation showing a circular conductor plate in the first embodiment;
FIG. 5 is a crosssectional sideview showing the same circular conductor plate;
FIG. 6 is a partially developed perspective view showing an assembly of the same exciting coils and the same conductor plates;
FIG. 7 is a crosssectional sideview showing a distribution of magnetic fluxes in the first embodiment in case an ac voltage is applied thereon;
FIG. 8 is an elevation showing the state of eddy currents flowing in the same circular conductor plate;
FIG. 9 is a crosssectional sideview showing a distribution of magnetic fluxes in a conventional plunger type electromagnet;
FIG. 10 is a crosssectional sideview showing a second embodiment of the same plunger type electromagnet according to the present invention;
FIG. 11 is an elevation showing a circular conductor plate in the second embodiment;
FIG. 12 is a crosssectional sideview showing the same circular conductor plate;
FIG. 13 is a crosssectional sideview showing a third embodiment of the same plunger type electromagnet according to the present invention;
FIG. 14 is an elevation showing a circular winding spool for an exciting coil in the third embodiment;
FIG. 15 is a crosssectional sideview showing the same winding spool;
FIG. 16 is a crosssectional sideview showing a distribution of magnetic fluxes in the third embodiment in case an ac voltage is applied thereon;
FIG. 17 is a crosssectional sideview showing an assembly of an exciting coil and magnetic cores in another type of electromagnet according to the present invention;
FIG. 18 is an elevation showing an assembly of an exciting coil and magnetic material cores in still another type electromagnet according to the present invention;
FIG. 19 is a crosssectional sideview showing the same assembly; and
FIG. 20 is a diagram showing characteristic curves of an exciting coil in an electromagnet according to the present invention.
Throughout different views of the drawings: x 1 , x 2 , x 3 are plunger type electromagnets; 1 1 , 1 2 , 1 3 are exciting coil portions; 2 is an exciting coil assembly ; 3, 6 are centrally located apertures of hollows; 5 1 , 5 2 are conductor plates; 5 3 is a winding spool; 7, 9 are slits; 8 is a short cylinder; 10 is a magnetic material frame; 20 is an acting portion; 21 is a guide cylinder; 22, 23 are magnetic material bodies; is a gap; 30 1 , 30 2 are electromagnets; 41 1 , 41 2 are exciting coils; 51 1 , 51 2 are fixed iron cores; 52 is a movable iron core; 53 is a bearing.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the present invention and operations thereof are precisely described hereinafter by referring to the accompanying drawings. In this connection, to avoid complicating the description, the same components and equivalent components are marked by the respectively same symbols, so as to omit respective descriptions.
In the first place, as a first embodiment of the present invention, a plunger type electromagnet x 1 will be described by referring to FIGS. 1 to 6.
In FIG. 1 showing a crosssectional sideview of a plunger type electromagnet x 1 , exciting coil portions 1 1 as shown in FIGS. 2 and 3 and conductor plates 5 1 as shown in FIGS. 4 and 5 are alternately stacked as shown in FIG. 6, so as to provide an exciting coil assembly 2 which features the present invention. This exciting coil assembly is entirely surrounded by a magnetic frame 10 formed of ferrimagnetic material as an enclosure and a pair of fixed and movable magnetic cylinders 22 and 23 which are formed of ferrimagnetic material also and are confronted with each other through a guide cylinder 21, a gap 24 being left therebetween, so as to be operated as an acting portion 20 of a plunger.
In this connection, the exciting coil portion 11 is regarded as one of plural annular sections formed by dividing an exciting coil of a conventional electromagnet and hence has a central hollow 3 as shown in FIGS. 2 and 3. The circular conductor plate 5 1 has an outer diameter substantially the same as that of the exciting coil portion 1 1 and a central hollow 6 having an inner diameter which is a little smaller than that of the central hollow 3 of the exciting coil portion 1 1 . Further, plate 5 1 has a radial slit 7 extended from the central hollow 6 to a periphery thereof. Plural exciting coil portions 1 1 and plural conductor plate 5 1 are alternately, coaxially and closely arranged in series as shown in FIG. 6, so as to compose the exciting coil of the electromagnet.
In this exciting coil assembly, the guide cylinder 21 formed of dielectric material is fixedly inserted through the central hollows 3 and 6 of the exciting coil portions 1 1 and the circular conductor plates 5 1 which are alternately stacked, and which define a centrally located cylindrical volume of substantially uniform diameter. Further, in this guide cylinder 21, the fixed and the movable magnetic material cylinders 22 and 23 are confronted with each other so that the gap 21 is left therebetween.
Accordingly, when an ac or dc voltage is applied across the exciting coil 2 assembly, magnetically exciting currents flow in each of exciting coil portions 1 1 and hence induce magnetic fluxes in the magnetic frame 10 and eddy currents in each of conductor plates 5 1 . The which eddy currents are obstructed by each of the slits 7 and then converged around the central hollows 6, so as to induce magnetic fluxes in these hollows 6. As a result, all of these magnetic fluxes flow through the fixed and the movable magnetic material cylinders 22 and 23 and hence the attracting force is effected between magnetic cylinders 22 and 23 through the gap 24. Consequently, the movable magnetic cylinder 23 is attracted toward the fixed magnetic cylinder 24 so as to act as a piston of the plunger.
In the above mentioned first embodiment Of the present invention, when an ac voltage is applied across the exciting coil assembly 2, magnetic fluxes are distributed in the electromagnet x 1 as shown in FIG. 7. In this connection, when ac magnetic fluxes are generated by the application of an ac voltage to the exciting coil portions 1 1 , an electromotive force in the direction opposite to the exciting current is generated in the circular conductor plate 5 1 , in the peripheral portion of which eddy currents i 1 flow in response to this electromotive force as shown in FIG. 8. The eddy currents il are obstructed by the radial slit 7 and turned toward the central hollow 6, and, as a result, eddy currents i 2 converged around the central hollow 6 flow in the same direction as that of the exciting current, so as to converge ac magnetic fluxes in the central hollow 6.
A comparison of the magnetic flux distribution according to the present invention as shown in FIG. 7 with the magnetic flux distribution in a conventional plunger type electromagnet shown in FIG. 9, which corresponds to the embodiment x 1 comprising exciting coil portions 1 1 without the circular conductor plates 5 1 inserted therebetween, an be made by comparing 9. In the conventional electromagnet of FIG. 9, FIG. 7 and leakage magnetic fluxes through the exciting coil portions 1 1 , which are obstructed by the conductor plates 5 1 in the embodiment x 1 , are remarkably increased, so that the effective magnetic fluxes, which pass through the movable magnetic cylinder positioned in the central portion of the electromagnet, are decreased in response to the increase of leakage magnetic fluxes, and, as a result, the attracting force is remarkably reduced.
In short, according to the present invention, the leakage magnetic fluxes through the exciting coil portions are reduced in response to the function of the eddy currents flowing in the conductor plates and hence almost all of the generated magnetic fluxes are converged within the central hollows 6 and, as a result, the attracting force is remarkably intensified.
In a second embodiment of the invention, a plunger type electromagnet designated x 2 is shown in FIG. 10 to 12 as a second embodiment of the present invention. The difference of this second embodiment x 2 from the aforesaid first embodiment x 1 is as follows.
Plural exciting coil portions 1 2 are formed in the same way as those of the first embodiment x 1 shown in FIGS. 2 and 3, so as to provide the exciting coil assembly 2.
In this exciting coil assembly, a circular conductor plate 5 1 , which is formed in the same way as that of the embodiment x 1 shown in FIGS. 4 and 5, is arranged at one end of the exciting coil assembly 2. At the other end thereof and in each of the interspaces of the exciting coil portions 1 2 , plural conductor plates 5 2 are arranged, each of which has a circular conductor plate portion having the same configuration as that of the embodiment x 1 shown in FIGS. 4 and 5. Further, a short hollow cylinder 8 which has an inner diameter which is the same as that of the central hollow 6 of the circular portion, is coaxially extended on one side only toward the conductor plate 5 1 by substantially the same length as the thickness of the exciting coil portion 1 2 . The short hollow cylinder 8 has a radial slit as shown in FIGS. 11 and 12, which slit 9 is continued with the radial slit 7 formed on the circular plate portion.
Consequently, in the second embodiment x 2 , the convergence of eddy currents around the central hollows 6 and the obstruction of leakage magnetic fluxes are improved by providing an electrically continuous arrangement of plural conductor plates in contact with each other, as a readily manufacturable unitary structure, through short hollow cylinders individually extended from each of the conductor plates.
In a third embodiment of the invention, a plunger type electromagnet marked by x 3 is shown in FIGS. 13 and 15. The difference of this third embodiment x 3 from the aforesaid second embodiment x 2 is as follows.
In the third embodiment x 3 , the circular conductor plates 5 1 and 5 3 in the second embodiment x 2 are serially arranged such that each of the slits 7 and 9 of all of these circular conductor plates 5 1 and 5 2 are unitarily continued, so as to provide a winding spool 5 3 of unitary structure as shown in FIGS. 14 and 15 for the exciting coil assembly.
In the aforesaid second and third embodiments of the present invention, when the ac voltage is applied across the exciting coil assembly 2, magnetic fluxes are distributed in the electromagnet x 2 and x 3 as shown in FIG. 16, which is substantially the same as shown in FIG. 7. Accordingly, a similar or improved result as achieved in that the leakage magnetic fluxes are decreased in response to the induced eddy currents and hence the effective magnetic fluxes in the central portion thereof are increased, so as to intensify the attracting force according to the electrically continuous structure of conductor plates inserted between exciting coils.
In all of the embodiments, the magnetic flux converging type exciting coil assembly, which is featured by the present invention, is applied on the plunger type electromagnet. In connection with these embodiments, this magnetic flux converging type exciting coil assembly can be applied also on a different type electromagnet, for example, a hinge type electromagnet as shown in FIG. 17. FIG. 17 shows an electromagnet 30 1 of a type such that an exciting coil 41 1 is wound on a leg of a fixed iron core 51 1 , while a movable iron core 52 is rotatably affixed to another leg of the fixed iron core 51 1 . In this type of electromagnet, the exciting coil 41 1 can be replaced with the exciting coil assembly according to the present invention, so as to obtain a function and an effect which are similar those obtained with the aforesaid embodiments. In this connection, the same function and effect are obtained with a solenoid type electromagnet.
FIGS. 18 and 19 show an electromagnet 30 2 of such a type wherein an exciting coil 41 2 and an iron core 51 2 are comprised as the subjective bodies, which is used in a case such that iron plates and the like are attracted and moved by a crane or the like. When the electromagnet 30 2 of this type is used as an ac electromagnet, the exciting coil 41 2 can be replaced with the aforesaid exciting coil assembly according to the present invention, so a function and an effect which are similar to those obtained in the aforesaid embodiments.
In case the electromagnets of the aforesaid embodiments are applied with a dc voltage, the increases with the lapse of time of the exciting current flowing in the exciting coil is indicated by curves shown in FIG. 20. In FIG. 20, a dotted curve indicates the exciting current when the time constant T 1 of the exciting coil is large, while a solid curve indicates the exciting current when the time constant T 2 is small. As is apparent from these curves, the smaller the time constant of the exciting coil, the more rapid the riseup of the exciting current becomes and hence the more rapid the attracting force increases so as to realize a high speed electromagnet.
On the other hand, when an ac voltage is applied to the electromagnets of the aforesaid embodiments, eddy currents are induced in the conductor plates 5 1 , 5 2 or in the winding spool 5 3 , so as to prevent the leakage of magnetic fluxes and hence to increase the effective magnetic fluxes required for generating the attracting force.
In addition, in the transient condition immediately after a dc voltage is applied to these electromagnets, eddy currents flow in a manner which is similar to the case in which an ac voltage is applied to the electromagnet. That is, in this transient condition, eddy currents are obtained which function in a manner similar to the secondary eddy currents in the case that an ac voltage is applied. As a result, the primary input current is increased. Consequently, the time constant of the exciting coil is equivalently reduced and hence the response speed of the electromagnet is raised, so as to realize a high speed electromagnet.
As is apparent from the above description, according to the present invention, the rise of the exciting current in response to the voltage application is accelerated by the function of eddy currents flowing in the conductor plates or the winding spool which are used for the exciting coil assembly, as if the time constant of the exciting coil is reduced, and hence the attracting force is rapidly increased. As a result, provision of a magnetic flux converging type high speed electromagnet which is steadily operated is facilitated. | A magnetic flux converging type high speed electromagnet comprising a magnetic frame and an exciting coil assembly positioned within the frame. The exciting coil assembly includes a plurality of series-connected exciting coil portions spaced from each other along a longitudinal axis and a plurality of conductor plates interposed between the coil portions. Each of the conductor plates is provided with a hollow cylindrical member having a slit extending in the longitudinal direction which is continuous with a radial slit in the conductor plate, and each of the hollow cylindrical members extends along the longitudinal axis from a corresponding conductor plate toward a first end of the magnetic frame. A first end conductor plate not having the hollow cylindrical member is interposed between the first end of the magnetic frame and an adjacent exciting coil portion of the exciting coil assembly. A second end conductor plate having a hollow cylindrical member is interposed between a second end of said magnetic frame and another adjacent exciting coil portion of the exciting coil assembly. | 7 |
This is a non-provisional application claiming the benefit of U.S. Provisional Application No. 61/501,685, filed Jun. 27, 2011.
FIELD OF THE INVENTION
This invention relates to the inspection and/or servicing of fluid carrying pipes, such as mains water systems.
BACKGROUND OF THE INVENTION
Within the water industry, there is an increasing demand for routine repair works and maintenance/inspection works to be carried out without disruption of the water network services. Thus, there is a desire to maintain operational pressures and flows. In addition, it is desirable to minimise the amount of excavation required to find the location of leaks in underground pipes.
It is known therefore to introduce a camera into a pipe for detecting leaks by means of visual internal inspection. However, many difficulties arise in the feeding of a camera over a long distance. Furthermore, visual inspection is not fully reliable in detecting leaks.
SUMMARY OF THE INVENTION
According to a first aspect of the invention, there is provided a pipe inspection system, comprising an inspection head at the end of a flexible shaft, wherein the inspection head comprises a rigid distal end portion and a rigid intermediate portion spaced from the distal end portion by a flexible region,
wherein the flexible region comprises a series of sections with pivotal connections between adjacent sections which allow pivoting about two orthogonal axes, wherein the range of pivoting between adjacent sections is limited such that the complete series can be pivoted by a maximum angle of between 80 and 100 degrees.
This arrangement defines a mechanical linkage which can form tight bends to ease insertion of the pipe inspection head along a pipe. The linkage can be passive so that it follows the contours of the pipe along which the system is being fed.
Preferably, a central hollow tube runs along the inside of the sections. This can carry signal cables to the inspection head. However, it can also function as a biasing arrangement, to urge the shaft back towards a straight configuration. It can also have some plasticity, so that a pre-bend can be held by the tube, which tends to bias the head to deflect in a certain direction. Thus, a pre-bend can be applied, and this helps the inspection head to be steered around a first (known) obstacle when it is inserted into the pipe.
According to a section aspect of the invention, there is provided a flexible guide for guiding insertion of a pipe inspection system into a pipe, the flexible guide comprising a series of sections with a pivotal connection between adjacent sections which allows pivoting about an axis, wherein the range of pivoting between adjacent sections is limited such that the complete series can be pivoted by a maximum angle of between 80 and 100 degrees, wherein the inner surface of each section is provided with a roller arrangement for guiding a pipe inspection system shaft which passes though the centre of the sections.
This arrangement provides a low friction bend through which the pipe inspection system shaft can be fed. By reducing the friction of bends in the shaft, the range to which the inspection head can be inserted is increased.
A first design of the flexible guide has a stop, which is arranged such that when the stop reaches a surface, the flexible guide has been bent by 90 degrees to define a bend from a direction normal to the surface to a direction parallel to the surface. This can be used to form a 90 degree bend simply by urging the guide against a surface. For example, it can be urged against the base of a fire hydrant column to form a bend from the column direction to a direction along which a connection pipe runs.
The bend is formed passively. For example, the pivotal connections can comprise (non-driven) hinges which connect the sections together. The bending is in one direction only, but the direction can be chosen by suitable choice of the angular orientation. The sections can be annular circular members.
In a second design, the sections are coupled together by cables which run along the sections at different circumferential positions, wherein the cables are fixed to an end of the guide, such that tensioning one cable forms a bend in the guide.
This provides an actively driven arrangement which can be steered by suitable driving of the cables. Four cables can be provided. The cables can pass through holes in connecting balls, and the surfaces of the balls define pivoting surfaces. The cables then form the connections between sections as well as enabling active driving of the bending function. The surfaces of the balls provide smooth pivoting regions between the sections.
The cables are preferably positioned towards the outer radius of the sections, and the roller arrangement is provided nearer the centre. The roller arrangement guides the shaft of the inspection system, which passes along the centre. The sections can be annular circular members.
According to a third aspect of the invention, there is provided a pipe inspection system, comprising an inspection head at the end of a flexible shaft, wherein a drive mechanism is provided spaced from the end portion, wherein the drive mechanism comprises a rotary bearing mounted on the shaft, and an expandable web which is attached to the rotary bearing by support rods which are pivotally connected to the rotary bearing such that they can contract to collapse the web around the shaft or expand to form an open web which functions as a drive mechanism driven by the fluid flow in the pipe.
This provides a web (like a parachute) for urging the inspection head along the pipe. It can be collapsed when the inspection head is inserted into the pipe, for example by a fixing which can be remotely removed. For example a Velcro tab can hold the tab against the shaft during initial insertion into the pipe. The rotary bearing prevents the inspection system shaft becoming twisted.
The support rods can comprise spring steel.
The invention also provides a pipe inspection system, comprising:
an inspection head at the end of a flexible shaft; and
a flexible guide for guiding insertion of the inspection head into a pipe, the flexible guide comprising the passive guide of the invention and defining a first bend after the point of insertion of the inspection head into the pipe.
The system can further comprise the actively shaped guide of the invention and defining a second bend after the point of insertion of the inspection head into the pipe.
The system of the invention can be installed through a fire hydrant.
BRIEF DESCRIPTION OF THE DRAWINGS
Examples of the invention will now be described in detail with reference to the accompanying drawings, in which:
FIG. 1 shows a known way for an inspection/repair system to be introduced into a pipe;
FIG. 2 shows an example of a known inspection/repair system;
FIG. 3 shows a first example of a flexible head for a pipe inspection system;
FIG. 4 shows a first example of a flexible head of the invention for a pipe inspection system;
FIG. 5 shows a first example of a bendable guiding member for a pipe inspection system;
FIG. 6 shows a second example of a bendable guiding member for a pipe inspection system;
FIG. 7 shows an example of a flow driven drive mechanism for a pipe inspection system;
FIG. 8 is used to explain how the pipe inspection system is inserted into a pipe; and
FIG. 9 is used to explain how the different aspects of the system of the invention can be used for a pipe inspection system inserted through a fire hydrant.
DETAILED DESCRIPTION
The invention relates to servicing and monitoring equipment for the interior of pipes.
Before describing the system of the invention, it will first be explained how this type of system can (in known manner) be launched into a pipe of a water mains system using a launch chamber, such that operational pressures and flows within the water system can be maintained.
FIG. 1 shows the basic layout. A mains water pipe 10 carries a pressurised water flow 12 . At a point along the pipe 10 , there is an existing fire hydrant, which comprises a riser section 14 and a valve section 16 . The valve section 16 has a control handle 18 which controls the flow of water from the mains pipe to an outlet 20 of the fire hydrant.
A launch chamber 22 can be provided in the form of a cover used for launching equipment into the mains water flow and which is coupled to the outlet 20 .
FIG. 1 shows a control rod 24 passing through the chamber 22 , and used to push a device 26 into the mains pipe 10 from an initial launch position shown as 28 .
The invention relates specifically to the equipment used to feed the device into the pipe and to aspects of the device 26 which assist this. FIG. 2 shows a known system in more detail.
The system comprises a feed cable 30 , with an inspection head 32 at a remote end of the feed cable. The inspection head comprises a camera with a light ring for illuminating the path in front. It also includes a sonde (acoustic output probe) used to enable location of the head from above the ground, and a hydrophone for detecting sound within the interior of the pipe.
The head acts as a lead device at the remote end of the cable 30 , and the other devices are positioned in series behind the inspection head.
The camera is used to relay real-time images, and the hydrophone is used to listen for frequency ranges identifying leaks within pipework when the head 32 passes such failures or defects.
The head 32 includes a guiding portion 34 which has a guide roller 35 (such as wheel, bearing or track) mounted at the remote end of the feed cable. The guide wheel has a rotation axis perpendicular to the length of the feed cable, i.e. it rolls as the feed cable moves along the pipe. The roller may comprise a series of rollers. However, the axis (or the axis of one of the rollers) is offset from the elongate feed cable axis, so that the head 32 rests on the wheel, with the roller 35 in contact with the pipe inner wall, and the camera in the centre of the pipe.
The feed cable 30 is rotatable about its elongate axis (see arrow 36 ), thereby to change the angular position of the guide wheel within the pipe.
This means the angular position of the wheel can be used to steer the head 32 as it advances in the pipe. By locating the guide wheel within the field of view of the camera (i.e. in front of the camera), the path of the pipe ahead can be visually inspected as well as the current angular orientation of the wheel. Adjustment to the angular orientation can then be made so that the head steers in the desired direction when the feed cable 30 is advanced further.
An ultrasound probe and an ultrasound sensor (together forming an ultrasound head 37 ) are provided along the feed cable 30 . The ultrasound signals are processed and displayed on a display. The resulting ultrasound image provides a representation of the properties of the pipe wall. To do this, the ultrasound signal is scanned around the inner circumference to build up a full image.
FIG. 2 also shows a repair head 38 which enables release of repair materials to a desired location of the pipe.
The different components in FIG. 2 are typically spaced by around 15 cm, and the total length of the cable can be around 100 m. The cable has an outer diameter of approximately 12 mm (typically 10-25 mm) and maximum diameter of the components along the cable can be 22 mm.
The system described above is known from WO2010/100480.
This invention concerns particularly the way the device is fed into and along the water pipe, and relates to various design aspects of the system. Furthermore, the invention facilitates the use of the system with pillar type fire hydrants, for example with a lateral connection pipe between the main water pipe and the vertical fire hydrant pillar (as shown in FIG. 9 described below).
Whilst water mains inspection and assessments are the primary function of the system, the system may also be utilised within the gas and oil pipe-works.
FIG. 3 shows an example of sensor head design which makes the path around bends easier.
The sensor head leading end incorporates a colour camera system 40 with light ring and hydrophone. The sensor head rear 42 incorporates a sonde and cable connector 45 for connection to a control cable or other systems. The front 40 and rear 42 are connected via a flexi-joint or spring arrangement 44 .
The system has a miniature size (for example length 200 mm-250 mm and integrates various technologies into one package. The camera system allows for real-time viewing whilst the hydrophone is used to listen for frequency ranges identifying leaks within pipe-work when the system passes such failures/defects. The geometry of the sensor heads including the spacing between the front and rear section and a pre-set offset angle of the flex-joint make this process possible through pillar style fire hydrants.
A pre-set offset angle is used to provide a bias so that the head tends to bend in one direction when pushed into a pipe. The direction of the pre-set bend can be matched to the direction of a bend in the pipe by twisting the head while viewing with the camera.
The rear part 42 has a connection 45 which incorporates a thread which allows engagement onto the main body and also includes an O ring seal acting as the pressure boundary as well as a grove for a location pin or dowel to prevent releasing when required.
The inside of the rear connector 45 is hollow in profile where a small 6 way electrical connector is housed. The geometry is such to allow all features within the same head over a maximum of 22 mm outside diameter.
In FIG. 3 , the joint is shown as a spring.
A more complex mechanical joint is shown in FIG. 4 . The top part shows the connector straight and the bottom part shows the bend.
The mechanical joint is in the form of an engineered assembly which can be used between the sensor head halves. The mechanical joint allows a pre-set bend radius to be held in form when an end loading is applied.
The joint comprises a series of sections 46 , each section pivotally mounted to the next by two orthogonal axes 48 perpendicular to the length of the joint. In this way, each section is coupled to the next by an arrangement like a constant velocity (CV) joint which allows movement in all directions.
The amount one section can pivot relative to the next (in both pivot directions) is limited by skirts which abut when the joint is bent, so that the complete length of sections can bend by around 90 degrees. Thus, the profile of each link is such as to provide a mechanical stop at a pre-defined angle to ensure the joint will not bend beyond this angle. The joint may incorporate as many links as necessary.
A nylon tube runs along the centre. This urges the joint to return towards its straight position, but it can hold a pre-bend which biases the joint to bend in a certain direction. Thus, the internal tube through the assembly generally causes the assembly to return to its original position when end loading is released but allows a pre-bend to be applied.
The assembly makes it possible to force the sensor head or other such head around 90 degree bends such as at the bottom of a pillar style fire hydrant and the T-Piece from the fire hydrant to the actual water pipe (seen in FIG. 9 ). This provides a rugged system to be used instead of a spring between the end sections as in FIG. 3 .
The mechanical joint is attached to the sensor front and rear bodies via screw threads and locking holes are positioned to allow locking pins or wire to be used. Each link 46 of the flexible joint is identical with the exception of the front and rear which contain a female thread for mating purposes.
FIG. 5 shows an internal roller mechanism 50 . This is used as a flexible guide for introducing the sensor probe into the fire hydrant (or other pipework). If the sensor cable has to pass multiple bends, reducing the friction at some of the bends will increase the distance that the cable can be inserted. The arrangement 50 of FIG. 5 is used to form a low friction 90 degree bend at the base of the fire hydrant shaft (as shown in FIG. 9 ).
The internal roller mechanism 50 is thus generally an assembly to assist with the installation of sensor heads into pipes and in particular its primary purpose is to create a safe path for the umbilical cable controlling the sensor head. This is critical for such installations into pipework. The assembly's key feature includes the ability to open out and pass through small access holes within the pipework. These are namely pressure tapings and/or fire hydrants, however the system may be applied to any orifice.
The roller mechanism will under load, hold a specific bend radius (typically 90 degrees) and lock into position until the loading it released.
The roller mechanism comprises a series of sections 52 which are hinged to each other by hinges 54 . They hinge in one direction only so that a bend is only formed in one direction. The bend radius of the cable, which is passed internally through the mechanism, is also controlled by miniature rollers 56 on bearings to aid cable protection and reduce friction to a minimum. The roller mechanism is mounted over the cable from the free end opposite the sensor head (since the sensor head cannot pass through it).
The assembly includes formed angled plates 58 which are held together by joints and each plate houses a number of rollers. A rear stop plate 59 is mounted to the assembly which ensures the device opens to the 90 degree angle by acting as a depth stop. This minimises stresses through the formed plates if excessive vertical force is applied during installation. The depth stop is designed so that the when seated down, the sections form the desired curve. The sections do not need to be sprung or biased so that it is a passive rather than active component.
FIG. 6 shows a steerable (i.e. active) internal roller mechanism, again forming a flexible guide. The steerable internal roller mechanism is an assembly with a primary function to assist umbilical cables which support sensor heads, however it may be used to pass any cables through.
The top part shows the control arrangement, the middle part shows the mechanism in a straight configuration and the bottom part shows the bent configuration.
Whereas the passive arrangement of FIG. 5 is used as the first bend after the point of insertion, the arrangement of FIG. 6 can be used to navigate a bend further in the pipework. Again, the aim is to reduce the friction of the bend so that the reach of the sensor head is increased.
The assembly consists of several circular links 60 . Four control wires 62 pass through the links. The control wires pass through balls 64 spaced at 90 degrees around the circumference of the sections. The control wires connect the sections together.
When loading is applied to the control wires, a controllable reaction is induced which allows the assembly to be controlled with regards to angles and positions. Each link also incorporates a number of miniature rollers which provides a clear, friction free path for a cable to pass internally. These rollers 66 define the internal passageway and provide a low friction bearing for the internal cable. This ensures cables can pass freely even when tight angles are formed. The rollers are mounted on four shafts in a direction tangential to the circular section.
Control of the assembly is for example by a worm and wheel gear box. This provides control in all directions and also allows the assembly to be locked into position.
The cables are anchored on both the front and rear of the assembly to ensure controllable bending may be induced. This particular assembly can for example allow 12 mm diameter cables to be passed through, however not restricted to this diameter. The control wire anchor point on the rear of the assembly is connected to an installation tube, however the control cable may serve as the installation rod if necessary. The maximum angle is controlled by the number of segments due to the clearance between each segment acting as a stop. This assembly may run fewer or more segments if required.
FIG. 7 shows an agitator drogue (parachute or sail, which will generally be termed a “web”). The agitator drogue 70 is an assembly which holds the sail parachute shape 72 into a flat (open) position allowing the fluid to drive the camera head along the length of the pipe.
The assembly comprises a main body 74 with angled holes where legs 76 in the form of rods are positioned. The legs provide the mounting points for the web 72 . The orientation is such to allow passing into and out of an access hole on pipework (namely pressure tapings and/or fire hydrants). The assembly also incorporates a bearing to allow swivelling at all times to prevent twisting of the camera cable to be induced under flow conditions. Thus, the main body 74 has fixed ends 77 , 78 and a central bush part 79 .
The assembly is fully splitable so it may be connected in situ. Typically the legs face forward, which ensures installation into small fittings and/or orifices is possible by controlling the release of the legs. Removal of the assembly is very simple due to the legs facing forward which allows it to be simply pulled from the fitting/orifice. Holding the sail/parachute into a preferred shape allows the minimum size or sail to be used for a given fluid flow rate. This is because the sail is held flat. Using legs in the form of rods as opposed to strings/wires/ropes prevent any tangling occurring. The agitator drogue assembly is configured to sit behind the camera head and clam onto the camera cable. This allows a full field of view throughout inspections of pipework.
FIGS. 8 and 9 shows the pillar fire hydrant launch arrangement. This is an assembly for attaching onto pillar fire hydrants and providing a controlled mechanical means for passing sensor heads and/or umbilical's into water pipes. The assembly requires the bonnet (lid) to be removed from the fire hydrant where the assembly is mounted to the hydrant body. Once into position the fire hydrant may be pressurised by opening the fire hydrant isolation valve and the seals within the launch arrangement make this possible.
This arrangement incorporates two roller mechanisms, the forward one is of the design of FIG. 6 and is steerable using control cables 80 routed through pressure seals to the operator above ground. This allows the front assembly to be navigated around bends and obstacles. Once in position the second (rear most) rollers are deployed again through pressure seals. The second is of the type shown in FIG. 4 . The rearmost roller arrangement is designed to prevent friction induced from passing an object around the lower section of the fire hydrant i.e. presenting a clear controlled path for an umbilical to pass.
A cable push pull system 82 is installed onto the launch arrangement (as illustrated) and the height varied using threaded bars protruding from the system mounting plate.
The push pull arrangement 82 can also control cable rotation and can be as described in WO2010/100480.
The camera cable 30 is passed through a secondary seal arrangement within a base plate which mounts over the fire hydrant column 90 , preventing water leakage from the pressurised assembly. The lead rollers or steerable rollers are also passed through a seal adjacent to the camera cable seal allowing both to operate independently of each other.
The position of the secondary (rear) roller arrangement 91 (of the type shown in FIG. 5 ) is controlled vertically by nuts reacting onto threaded bars 92 protruding from the mounting plate. These control the positions of installation rods 93 . Various adaptor plates may be installed onto the mounting plate to suite the hole patterns of all manufacturers of pillar style fire hydrants.
The roller arrangement 91 forms a bend to a connecting pipe 94 , which is at 90 degrees to the main pipe 96 . A primary (front) roller arrangement 98 (of the type shown in FIG. 6 ) forms the bend between the connecting pipe 94 and the main pipe 96 and is controlled by the cables 80 .
The system has been described in connection with the inspection or repair of water pipes, and is for gathering information of water main structure and integrity in this example. However, the apparatus can also be used for gas and oil pipes, or other fluid channels.
The example above shows the system inserted at a hydrant. However, the apparatus may equally be inserted at pressure fittings
Various modifications will be apparent to those skilled in the art. | A pipe inspection system comprises an inspection head at the end of a flexible shaft, wherein the inspection head comprises a rigid distal end portion and a rigid intermediate portion spaced from the distal end portion by a flexible region. The flexible region comprises a series of sections with pivotal connections between adjacent sections which allow pivoting about two orthogonal axes, wherein the range of pivoting between adjacent sections is limited such that the complete series can be pivoted by a maximum angle of between 80 and 100 degrees. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates generally to oil well logging and monitoring. More particularly, the present invention relates to determining the acoustic properties of a borehole fluid.
[0005] 2. Description of the Related Art
[0006] To recover oil and gas from subsurface formations, wellbores or boreholes are drilled by rotating a drill bit attached at an end of a drill string. The drill string includes a drill pipe or a coiled tubing that has a drill bit at its downhole end and a bottom hole assembly (BHA) above the drill bit. The wellbore is drilled by rotating the drill bit by rotating the tubing and/or by a mud motor disposed in the BHA. A drilling or wellbore fluid commonly referred to as the “mud” is supplied under pressure from a surface source into the tubing during drilling of the to wellbore. The drilling fluid operates the mud motor (when used) and discharges at the drill bit bottom. The drilling fluid then returns to the surface via the annular space (annulus) between the drill string and the wellbore wall or inside. Fluid returning to the surface carries the rock bits (cuttings) produced by the drill bit as it disintegrates the rock to drill the wellbore.
[0007] A wellbore is overburdened when the drilling fluid column pressure is greater than the formation pressure. In overburdened wellbores, some of the drilling fluid penetrates into the formation, thereby causing a loss in the drilling fluid and forming an invaded zone around the wellbore. It is desirable to reduce the fluid loss into the formation because it makes it more difficult to measure the properties of the virgin formation, which are required to determine the presence and retrievability of the trapped hydrocarbons. In underbalanced drilling, the fluid column pressure is less than the formation pressure, which causes the formation fluid to enter into the wellbore. This invasion may reduce the effectiveness of the drilling fluid.
[0008] A substantial proportion of the current drilling activity involves directional boreholes (deviated and horizontal boreholes) and/or deeper boreholes to recover greater amounts of hydrocarbons from the subsurface formations and also to recover previously unrecoverable hydrocarbons. Drilling of such boreholes require the drilling fluid to have complex physical and chemical characteristics. The drilling fluid is made up of a base such as water or synthetic material and may contain a number of additives depending upon the specific application. A major component in the success the drilling operation is the performance of the drilling fluid, especially for drilling deeper wellbores, horizontal wellbores and wellbores in hostile environments (high temperature and pressure). These environments require the drilling fluid to excel in many performance categories. The drilling operator and the mud engineer determine the type of the drilling fluid most suitable for the particular drilling operations and then utilize various additives to obtain the desired performance characteristics such as viscosity, density, gelation or thixotropic properties, mechanical stability, chemical stability, lubricating characteristics, ability to carry cuttings to the surface during drilling, ability to hold in suspension such cuttings when fluid circulation is stopped, environmental harmony, non-corrosive effect on the drilling components, provision of adequate hydrostatic pressure and cooling and lubricating impact on the drill bit and BHA components.
[0009] A stable borehole is generally a result of a chemical and/or mechanical balance of the drilling fluid. With respect to the mechanical stability, the hydrostatic pressure exerted by the drilling fluid in overburdened wells is normally designed to exceed the formation pressures. This is generally controlled by controlling the fluid density at the surface. To determine the fluid density during drilling, the operators take into account prior knowledge, the behavior of rock under stress, and their related deformation characteristics, formation dip, fluid velocity, type of the formation being drilled, etc. However, the actual density of the fluid is not continuously measured downhole, which may be different from the density assumed by the operator. Further, the fluid density downhole is dynamic, i.e., it continuously changes depending upon the actual drilling and borehole conditions, including the downhole temperature and pressure. Thus, it is desirable to determine density of the wellbore fluid downhole during the drilling operations and then to alter the drilling fluid composition at the surface to obtain the desired density and/or to take other corrective actions based on such measurements.
[0010] As noted above, an important function of the drilling fluid is to transport cuttings from the wellbore as the drilling progresses. Once the drill bit has created a drill cutting, it should be removed from under the bit. If the cutting remains under the bit it is redrilled into smaller pieces, adversely affecting the rate of penetration, bit life and mud properties. The annular velocity needs to be greater than the slip velocity for cuttings to move uphole. The size, shape and weight of the cuttings determine the viscosity necessary to control the rate of settling through the drilling fluid. Low shear rate viscosity controls the carrying capacity of the drilling fluid. The density of the suspending fluid has an associated buoyancy effect on cuttings. An increase in density usually has an associated favorable affect on the carrying capacity of the drilling fluid. In horizontal wellbores, heavier cuttings can settle on the bottom side of the wellbore if the fluid properties and fluid speed are not adequate. Cuttings can also accumulate in washed-out zones. Determining the density of the fluid downhole provides an indication of whether cuttings are settling or accumulating at any place in the wellbore.
[0011] In the oil and gas industry, various devices and sensors have been used to determine a variety of downhole parameters during drilling of wellbores. Such tools are generally referred to as the measurement-while-drilling (MWD) tools. The general emphasis of the industry has been to use MWD tools to determine parameters relating to the formations, physical condition of the tool and the borehole. Very few measurements are made relating to the drilling fluid. The majority of the measurements relating to the drilling fluid are made at the surface by analyzing samples collected from the fluid returning to the surface. Corrective actions are taken based on such measurements, which in many cases take a long time and do not represent the actual fluid properties downhole.
SUMMARY OF THE INVENTION
[0012] The problems outlined above are in large part addressed by a self-calibrated ultrasonic method of in-situ measurement of borehole fluid acoustic properties. In a preferred embodiment of the present invention, a method for determining a borehole fluid property includes (i) generating an acoustic signal within a borehole fluid, (ii) receiving reflections of the acoustic signal from the fluid, and (iii) analyzing a reverberation portion of the acoustic signal to determine the property. The analyzing of the reverberation portion may include obtaining a theoretical reverberation signal and relating the measured reverberation signal with the theoretical reverberation signal to determine the borehole fluid property.
[0013] In another preferred embodiment of the present invention, a processor adapted to provide real-time estimates of a borehole fluid property includes an input terminal and a processing portion. The input terminal receives a data signal corresponding to a reflected acoustic wave. The processing portion separates the data signal into a first reflection portion and a resonance portion and convolves the first reflection portion response to yield a theoretical reverberation response.
[0014] In yet another preferred embodiment of the present invention, a tool for measuring borehole fluid properties includes a body, an acoustic transducer, and a metal disk. The body houses the transducer and metal disk. A borehole fluid enters the tool through an opening in the body, flows in between the transducer and metal disk where it is measured, and exits the tool.
[0015] Thus, the present invention comprises a combination of features and advantages which enable it to overcome various problems of prior devices. The various characteristics described above, as well as other features, will be readily apparent to those skilled in the art upon reading the following detailed description of the preferred embodiments of the invention, and by referring to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] For a more detailed description of the preferred embodiment of the present invention, reference will now be made to the accompanying drawings, wherein:
[0017] [0017]FIG. 1A is a general schematic showing a tool in a preferred embodiment;
[0018] [0018]FIG. 2B is a cut-away view illustrating component parts of FIG. 1A;
[0019] [0019]FIG. 2 illustrates waveform reflection and reverberation;
[0020] [0020]FIG. 3 is a graph showing a received acoustic waveform;
[0021] [0021]FIG. 4 is a diagram illustrating the component parts of FIG. 3;
[0022] [0022]FIG. 5A is a diagram of a subterranean system built in accord with a preferred embodiment;
[0023] [0023]FIG. 5B is a diagram of the above ground system built in accord with a preferred embodiment;
[0024] [0024]FIG. 6 is a general flow diagram of a preferred embodiment;
[0025] [0025]FIG. 7A is a flow diagram of a preferred embodiment; and
[0026] [0026]FIG. 7B is a flow diagram of a preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] [0027]FIG. 1A illustrates a general overview of a tool submerged downhole. Shown are tool 10 , fluid vent 20 , formation 30 , and well fluid 210 . Fluid vent 20 provides a means for well fluid 210 to enter and exit tool 10 . While in tool 10 , well fluid 210 is measured for its acoustic properties.
[0028] [0028]FIG. 1B is a cross-sectional view of the tool showing acoustic measurement components. Inside tool 10 , where fluid vent 20 is located, are acoustic transducer 200 and metal disk 220 . As can be seen, well fluid 210 enters tool 10 , flows between acoustic transducer 200 and metal disk 220 , and exits tool 10 .
[0029] [0029]FIG. 2 illustrates the acoustic wave path and metal disk reverberations for a downhole acoustic wave. Shown are acoustic transceiver 200 , well fluid 210 and metal disk 220 . Well fluid 210 and disk 220 each has its own impedance, labeled Z m and Z s , respectively. Also shown is acoustic signal 250 , including first reflected portion 260 , disk reverberation portions 271 - 276 and transmitted wave portions 280 , 282 , 284 and 286 through the disk in the same well fluid.
[0030] To measure the reflection coefficient of the well fluid, the acoustic transceiver 200 sends out an ultrasonic impulse 250 , preferably with a characteristic frequency of about 500 kHz, then switches to the receive mode. The impulse frequency is preferably set at the expected resonance frequency of the disk. The sound impulse 250 travels through the well fluid 210 and strikes the disk 220 . The largest portion of the energy of the impulse is reflected back to the transducer as reflected wave 260 while a small amount of signal enters the disk as wave 280 . When the well fluid 210 is water, the reflected wave form has an amplitude of about 93% of the initial impulse. The portion of the signal that entered the disk is reflected back and forth between the disk/fluid interface and the disk/tool interface, as illustrated by wave reverberations 271 - 276 . At each reflection some energy is transmitted through the interface, dependent on the acoustic impedance contrast, and is either directed back toward the transducer or out into the tool. The signal inside the disk is quickly dissipated in this manner at a rate directly dependent on the acoustic impedance of the material outside the disk according to the equation:
R 1 =( Z 1 −Z 2 )/( Z 1 +Z 2 ) (1)
[0031] where R 1 is the reflection coefficient, and Z 1 and Z 2 are the impedances of the materials at the interface in question. In a preferred embodiment, the thickness of the metal disk is set to one half of the resonant wavelength of the transducer signal.
[0032] The acoustic transceiver 200 , now acting as a receiver or transducer, sees a waveform consisting of a loud initial reflection followed by an exponentially decaying reverberation signal. FIG. 3 illustrates the measured acoustic waveform received at the transceiver 200 . If time t=0 is the time of generation of the acoustic wave at the acoustic transmitter, then the time T tran represents the transit time (the time for the travel of this acoustic wave to the disk and back to the transceiver). Since the distance is fixed, the transit time T tran provides an indication of the acoustic velocity of the fluid. Also shown in FIG. 3 are the Time Offset, T off , and the Resonance Window, T win , both of whose significance is explained below.
[0033] [0033]FIG. 4 illustrates the individual waveforms, both first reflection and reverberations, that sum to provide the waveform of FIG. 3. The waveform received by the transducer is the sum of the initial reflection waveform with each reverberation waveform, where each reverberation is delayed an amount proportional to the width of the disk. Further, because the acoustic transducer is not a perfect transmitter, it “rings” somewhat upon the transmission of an acoustic wave. This transducer “ringing” also is included in the detected waveform, and may be accounted for by the present invention.
[0034] [0034]FIG. 5 illustrates a device built in accord with a preferred embodiment. Shown in FIG. 5A is acoustic transceiver 200 , analog-to-digital converter 500 , a processor 510 for recording start time and gain, waveform compression chip 520 , and multiplexer 530 . Waveform compression chip 520 could alternately be part of a processor. Also shown are downhole transmitter 540 connected to multiplexer 530 and telemetry cable 545 . Referring now to FIG. 5B, at the surface are located uphole receiver 550 , demultiplexer 560 , transmission line 564 carrying tool information to processor 590 for a data log 595 , transmission line 570 carrying gain and start time information to uphole processor 590 , and waveform decompression chip 580 . Attached to decompression chip 580 is processor 590 . Processor 590 generates data suitable for a log 595 .
[0035] Referring now to both FIGS. 5A and 5B, acoustic transceiver 200 collects data of metal disk reflection and reverberation. This acoustic waveform is digitized by analog-to-digital converter 500 and sent to processor 510 , which detects the first reflection from the digitized signal. Processor 510 then computes the relevant start time and transit time. Because the total waveform data may be greater than the bandwidth capacity of transmission line 545 , digital compression 520 is preferably performed. Suitable compressions include wavelet and ADPCM (Adaptive Differential Pulse Code Modulation) techniques, which work well for smoothly varying data. The compressed waveform from digital compression chip 520 is then multiplexed 530 with the other tool information. Downhole transmitter 540 sends this multiplexed data to the surface. Sending the data to the surface allows processing by faster, more sophisticated machinery.
[0036] This multiplexed data is received by uphole receiver 550 and is separated into component parts by demultiplexer 560 . Waveform decompression chip 580 provides the reconstructed waveform to processor 590 , which also receives start time information. Upon the determination of the reflection coefficient of the well fluid, processor 590 combines with position information and creates a log 595 .
[0037] [0037]FIG. 6 illustrates a general method for the present invention. In block 600 , an observed waveform is provided uphole for processing. In some embodiments, it may be desirable to stack waveforms (block 610 ). The waveform's transit time (T tran ) is obtained in block 620 , as well as the time windows T off and T win . The definition of transit time was explained above with reference to FIG. 3 and may be easily measured by a first reflection detector portion of processor 510 . T off and T win are then selected to obtain a time window T win that contains reliable reverberation information. T off , measured from the time of receipt for the initial reflection, is a time window that encompasses the initial reflection. As such, its duration is dependent upon the duration of the acoustic impulse transmitted by acoustic transceiver 200 and the nature of the drilling fluid. T off also preferably accounts for error introduced because of the real-world shortcomings of the acoustic transducer (transducer “ringing”), and thus T off may be slightly longer than if chosen theoretically. Nonetheless, T off is about 15 microseconds. T win is juxtaposed with T off and is a time window of interest because T win contains reverberation information uncontaminated by the first reflection. The duration of T win should be brief enough so that noise and reverberations occurring in the tool 10 do not make unreliable the received disk reverberation waveforms. Nonetheless, so that a reliable wave train containing sufficient data is obtained, T win preferably includes at least four reverberations. Thus, T win is about 12.8 microseconds.
[0038] The tool calibration may be obtained as follows. First, the reflection waveform defined by T off is transformed to the frequency domain by use of DFT (Discrete Fourier Transform). Referring back to FIG. 6, proper modeling applied to the first reflection signal 260 , as defined by T off , gives a theoretical prediction of what the reverberation waveform contained in T win should look like. To accomplish this, in block 630 the first reflection signal is transformed by Fast Fourier Transform (FFT) into its frequency domain equivalent. This yields S(ω). Because the modeling is done in the frequency domain, amplitude and phase errors are eliminated. This error elimination simplifies mathematical processing (and hence faster processing is obtained).
[0039] Alternately, instead of transforming each first reflection individually, to enhance accuracy, the first reflections from multiple firings may first be averaged and the result transformed in block 630 by FFT processing into the frequency domain to yield S(ω). A most reliable first reflection average may be obtained by discarding first reflections that have amplitudes above or below a preset deviation from a moving average of preceding first reflections.
[0040] In block 640 , a theoretical prediction of the reverberation waves is obtained by multiplying (convolution in time domain) the frequency-domain first reflection signal S(ω) with a frequency-domain theoretical response equation R(ω) to obtain a frequency domain version X(ω) of the reverberation signal x(t). Assuming a flat metal disk, the theoretical frequency domain response may be modeled by the following:
R ( ω ) = Z m - Z s Z m + Z s + 4 Z m Z s ( Z s - Z m ) ( Z m + Z s ) 3 1 - ( Z s - Z m Z m + Z s ) 2 - 2 ω C T V s - 2 ω C T V s ( 4 )
[0041] Where
[0042] R(ω)=the reflection coefficient for angular frequency co
[0043] Z m , Z s ,=impedances for mud and metal disk, respectively
[0044] V s =the speed of sound in the metal disk
[0045] C T =the thickness of the metal disk
[0046] The above equation assumes that the transducer generates waves having normal (i.e., perpendicular) incidence on the disk. V s , Z s , and C T can be measured very precisely as basic physical properties of the metal disk.
[0047] In block 640 the frequency domain signal X(ω) is transformed back into the time domain by use of an Inverse Fast Fourier Transform (IFFT). As such, block 640 provides the theoretical reverberation response x(t) for the observed initial reflection waveform(s) in the time domain. This theoretical reverberation response is also a function of the borehole fluid impedance Z m . Once the results are converted to the time domain, a relationship is established between the theoretical response and the received response. Next, a method is used to determine the borehole fluid properties in block 650 .
[0048] Two embodiments for relating theoretical and measured responses in block 640 include 1) a curve fitting method and 2) a non-linear waveform inversion method. Both methods calculate theoretical waveform response based on Equation 4. However, the curve fitting method uses fewer theoretical modeling steps than the inversion method.
[0049] [0049]FIG. 7A illustrates the curve fitting method, where a measurement equation is determined. As an initial matter, for a reverberation window of interest, T win , the natural log of the sum of the reverberation waveform amplitude (S w ) varies linearly with well fluid impedance. That is, a linear relationship between well fluid impedance and S w may be expressed as:
Z m =A+B ln(S w ) (6)
[0050] where S w is the sum of the reverberation waveform amplitudes and has the form:
S w = ∑ t x ( t ) ( 7 )
[0051] the lower case x(t) being the amplitude at any given point in the reverberation waveform contained in T win .
[0052] For the curve-fitting method, block 640 includes blocks 700 - 760 . In block 700 , an initial theoretical fluid impedance Z m is chosen. In block 710 , the theoretical response R(ω) is calculated in accordance with Equation 4. In block 720 , the first reflection is convolved with the theoretical response obtained in block 710 . In block 730 , the Inverse Fast Fourier Transform (IFFT) is performed to obtain a theoretical reverberation waveform. Next, the summed amplitudes of the theoretical reverberation waveform SW is determined in block 740 . In block 750 , the theoretical response R(ω) and reverberation waveform amplitude sum S w are stored. In block 760 , it is decided whether or not additional data is needed. If additional data is necessary, another theoretical fluid impedance Z m may be chosen in block 700 . To determine the coefficients in this linear relationship, steps 700 - 760 are repeated at least twice for different assumed fluid impedances Z m . Each time, the resulting sum S w is calculated. From these multiple points, (S w , Z m ), the coefficients A, B, can be determined using the least squares curve fitting in block 770 . With the relationship, the measured impedance Z m can be determined from the observed S w using Equation 7 in block 780 .
[0053] Lastly, in block 650 (FIG. 6), S w is substituted into Equation 6, and well fluid impedance Z m is determined. The acoustic velocity of the fluid may also be calculated in block 650 . Because the separation between the transducer and disk is known, the velocity is calculable from the measured transit time T tran . From the impedance (ρ) and velocity (v), the fluid density (Z m ) can be calculated due to the relationship: Z m =ρv.
[0054] As mentioned above, in a second embodiment, non-linear waveform inversion may be used in block 640 to determine the relationship between theoretical and measured reverberation. While the waveform inversion method is slower than the curve fitting method described above, it produces more accurate results because it matches entire reverberation waveform window using both amplitude and phase. As a result, many fluid acoustic properties including density and attenuation can be calculated simultaneously. A preferred method employs the Levenberg-Marquardt method. See generally W. Press et al., Levenberg-Marquardt Method , p. 542 (Numerical Recipes in C, 1988), incorporated herein by reference.
[0055] In the non-linear waveform inversion embodiment shown in FIG. 7B, fluid properties such as velocity, density, and attenuation are initially estimated in block 800 . In block 810 , the theoretical response R(ω) is calculated in accordance with Equation 4. In block 820 , the first reflection is convolved with the theoretical response obtained in block 710 . In block 830 , the Inverse Fast Fourier Transform (IFFT) is performed to obtain an estimated reverberation waveform. In block 840 , the error between the estimated and measured waveforms is determined. The error is calculated according to Equation 8.
Error=Σ|(observed−theoretical) 2 | (8)
[0056] In block 850 , the error calculated in block 840 is compared to a predetermined tolerance. If the calculated error is greater that the predetermined tolerance, another estimate is performed in block 800 using the Levenberg-Marquardt method. This cycle is repeated until the calculated error is less than the predetermined tolerance. When the calculated error is less than the predetermined tolerance, the estimated fluid velocity, density, and attenuation are accepted as the measured properties in block 860 .
[0057] While preferred embodiments of this invention have been shown and described, modifications thereof can be made by one skilled in the art without departing from the spirit or teaching of this invention. The embodiments described herein are exemplary only and are not limiting. For example, while the present invention has been described for use while drilling a well, it may also be used during completing and producing. Many variations and modifications of the system and apparatus are possible and are within the scope of the invention. Accordingly, the scope of protection is not limited to the embodiments described herein, but is only limited by the claims that follow, the scope of which shall include all equivalents of the subject matter of the claims. | The present invention finds the acoustic impedance of the drilling fluid using reflections from a precise metal disk, and therefrom the density of the drilling fluid. Because the reverberation characteristics of an acoustic wave depend in part on the acoustic wave shape, the first reflection from the metal disk may be used to calibrate the measurement. A method for determining a borehole fluid property is disclosed that includes (i) generating an acoustic signal within a borehole fluid, (ii) receiving reflections of the acoustic signal from the fluid, and (iii) analyzing a reverberation portion of the acoustic signal to determine the property. The analyzing of the reverberation portion may include obtaining a theoretical reverberation signal and relating the measured reverberation signal with the theoretical reverberation signal to determine the borehole fluid property. | 6 |
BACKGROUND TO THE INVENTION
This invention relates to a hydraulic control system for a roof support assembly of an underground mining installation.
A known type of roof support assembly is constituted by a plurality of identical roof support units positioned side-by-side along, for example, a longwall face. Each unit is provided with hydraulic advance ram means so that the units can be advanced individually, or in groups, to follow the advance of the mineral face being won. Such an assembly is known as a walking frame roof support assembly. Each roof support unit is typically constituted by a floor sill, a roof cap and a goaf shield, the roof cap being supported by hydraulic props which rest on the floor sill. Such a roof support assembly is provided with a hydraulic control system which is used to control the various operations of each of the units of the assembly, such as the retraction of the props prior to the advance of a unit, advance of that unit, and extension of the rams after the advance. The control system may be operated manually by either proximity or remote control, and the units may be controlled either individually or in groups.
Although the known hydraulic roof support control systems have proved quite reliable in practice, they do suffer from a number of disadvantages. In particular, when the props of a given roof support unit are retracted, the extent of this retraction depends entirely upon the degree of control exercised by the operating personnel. Consequently, there is a danger that, as the roof support units are advanced, the props are forcibly retracted to too great an extent. This is particularly dangerous when mining seams of small thickness. In the extreme case, the roof cap of a unit may be lowered to such an extent that, if sufficient attention is not paid, the face workers might suffer serious, or even fatal injuries by being crushed between the downward moving roof support parts and the floor of the working.
However, even where seams of large thickness are being mined, the roof caps of the roof support units may be lowered to an unnecessary extent during the advance operation. For example, if the roof caps of adjacent units bear against one another for guide purposes, their supporting and guiding functions may cease if the roof caps are lowered too far, so that considerable working difficulties can arise.
The aim of the invention is to provide a control system for a hydraulic roof support assembly which does not suffer from the disadvantages outlined above.
SUMMARY OF THE INVENTION
According to one aspect of the present invention, there is provided a hydraulic control system for a roof support unit of an underground mining installation, the roof support unit being provided with a roof cap supported by a hydraulic prop means, the control system comprising a valve for controlling the supply of pressurised hydraulic fluid to the prop means, and an actuator for closing the valve when the prop means has been retracted by a predetermined amount.
According to another aspect of the present invention, there is provided a control system for an underground mining installation, the control system comprising hydraulic roof-supporting prop means, a valve for controlling the supply of pressurized hydraulic fluid to the prop means, and an actuator for closing the valve when the prop means has been retracted by a predetermined amount.
Advantageously, the prop means is constituted by a plurality of hydraulic props each of which has a first working chamber, pressurisation of which causes retraction of that prop, and a second working chamber, pressurisation of which causes extension of that prop, said valve controlling, in use, the supply of pressurised hydraulic fluid to the first working chambers of the props. Preferably, the prop means is constituted by four props.
Said valve may be provided in a first supply line which leads to the first working chambers of the props, the first supply line being optionally connectible to a pressure line or a return line by actuation of a first control valve.
The provision of this valve ensures that the forcible retraction of the props is limited in a positive manner, and is not dependent upon correct action from operating personnel. Thus, retraction of the props to too great an extent is effectively prevented.
Preferably, said valve is a spring-loaded slide valve which is opened, against the force of its spring, by co-operation of the actuator and the slide.
The actuator may be constituted by a mechanical switching element such as a cam. Advantageously, the cam is fixed to a part movable, in use, with the retracting prop means, said valve being fixed to a stationary part of the installation in the path of the cam. Preferably, the cam is adjustably fixed to the roof cap of the roof support unit.
Advantageously, supply line means leads to the second working chambers of the props, the supply line means being optionally connectible to the pressure line or the return line by control valve means. The supply line means may be provided with servo-valve means for controlling the flow of pressurised hydraulic fluid to the second working chambers of the props. Preferably, the servo-valve means is spring biassed towards its closed position, and is openable, against this biassing force, by pressurizing its servo-piston means.
The servo-piston means may be pressurised via a control line leading from the first supply line on the outlet side of said valve. The servo-valve means may be openable, against the biassing force, by the pressure of hydraulic fluid in the supply line means when the supply line means is connected to the pressure line by the control valve means.
In a preferred embodiment, a pair of parallel supply lines constitute the supply line means, a respective servo-valve being provided in each of said parallel supply lines, the two servo-valve constituting the servo-valve means. In this case, the control valve means is constituted by second and third control valves, the second control valve being provided in one of the parallel supply lines and the third control valve being provided in the other parallel supply line. A first of the servo-valves may control the flow of pressurised fluid to the second working chamber(s) of at least one, but not all the props, and the second servo-valve controls the flow of pressurised fluid to the second working chamber of the or each of the remainder of the props. Where there are four props, each servo-valve controls the flow of pressurised fluid to the second working chamber of two of the props.
Advantageously, each of the parallel supply lines constituting the supply line means is provided with a respective branch line leading from the outlet side of the corresponding servo-valve and terminating in the return line, each branch line being provided with a respective pressure-relief valve.
Preferably, the control system further comprises overload protection means for providing pressurised hydraulic fluid to the prop means after said valve has closed and in the event of an overload acting on the prop means. Thus, even after said valve has limited the retraction of the prop means, further retraction of the prop means is possible in the event of an overload acting say on the roof cap. Since, in the event of such an overload, the roof support is pushed down very slowly, this does not constitute a serious danger to face workers.
Advantageously, the control line is connected to the outlet of the non-return valve.
BRIEF DESCRIPTION OF THE DRAWING
A control system for a hydraulic roof support assembly and constructed in accordance with the invention will now be described by way of example, with reference to the accompanying drawing, the single FIGURE of which is a circuit diagram of that part of the control system associated with one roof support unit of the assembly.
DESCRIPTION OF PREFERRED EMBODIMENT
Referring to the drawing, the roof support unit has four hydraulic props 10, 11, 12 and 13, each of which has an annular working chamber 14 which can be pressurised for the purpose of retracting the props. Each prop 10, 11, 12 and 13 also has a cylindrical working chamber 15 whch can be pressurised for the purpose of extending the props.
The control system includes a manually actuable control valve device 18 which is used to control the various operations of the roof support unit, namely the retraction and extension of the props 10, 11, 12 and 13, and the advance of the unit. The device 16 is constituted by three control valves 17, 18 and 19 each of which is a slide valve. These three valves 17, 18 and 19 can be combined to form a single composite slide valve, or they can be formed in a common control block. The input of each control valve 17 and 18 is connected to a hydraulic pressure line P by way a line 20 and to a hydraulic return line R by way of a line 21. Similarly, the input of the control valve 19 is connected to the pressure line P and the return line R by means of respective lines 22 and 23. The pressure and return lines P and R run along the entire face and supply pressurized hydraulic fluid to each of the roof support units.
The output side of the control valve 19 is connected, by way of a line 24, to the annular working chambers 14 of the four hydraulic props 10, 11, 12 and 13. A spring-loaded slide valve 25 is provided in the line 24. This valve 25 has a valve closure member 27 biassed towards its closed position by means of a spring 26, the closure member being liftable from its valve seat 29 by means of a slide 28. The valve 25 is actuated by means of a cam 30 which is fitted onto part of the roof support unit (for example the roof cap) that is lowered as the props 10, 11, 12 and 13 are retracted. The cam 30 has a raised portion 31 and a recessed portion 32 joined by an inclined portion 32a. The raised portion 31 contacts the slide 28 over the major part of the retraction stroke of the props 10, 11, 12 and 13 so that the closure member 27 is lifted from its valve seat 29 against the force of the spring 26, thus establishing a path for pressurising the working chambers 14 of the props. However, as soon as the slide 28 contacts the recessed portion 32 of the cam 30, the valve 25 closes under the action of the spring 26, thus cutting off the line 24 from further pressurisation from the pressure line P via the control valve 19.
Although the cam 30 is used to actuate the valve 25, any other suitable form of mechanical switching means could be utilised for this purpose. Moreover, instead of positioning the cam 30 on a movable part of the roof support unit and having the valve 25 stationary, the arrangement could be reversed by positioning the valve 25 on the movable part of the unit and having the cam 30 fixed.
At the output side of the valve 25, the line 24 is connected to the return line R via a branch line provided with a non-return valve 33. A control line 34 also leads from the line 24 at the output side of the valve 25, this control line 34 being connected to two servo-valves 35 and 36 which are arranged in parallel. Each of the servo-valves 35 and 36 has a control piston 37, a closure member 39, a valve seat 40 and a spring 38 which biasses the closure member towards the valve seat. As long as the pistons 37 are not pressurised via the control line 34, the valves 35 and 36 are closed owing to the biassing force of their springs 38.
The output side of the control valves 17 and 18, which are arranged in parallel, are connected to the input sides of the servo-valves 36 and 35 by respective lines 41 and 42. The output side of the servo-valve 36 is connected to the working chambers 15 of the props 10 and 11 by way of lines 43 and 45; and the output side of the servo-valve 35 is connected to the working chambers 15 of the props 12 and 13 by way of lines 44 and 46. The output sides of the servo-valves 35 and 36 are each connected to the return line R by way of branch lines incorporating respective pressure-relief valves 47 and 48.
The control system described above operates in the following manner. Assuming the various valves are in the positions illustrated (that is to say the control system is in the prop-retraction position), the pressure line P is connected to the working chambers 14 of the four props 10, 11, 12 and 13 via the line 22, the control valve 19, the line 24 and the valve 25, the valve 25 being open owing to the abutment of its slide 28 with the raised portion 31 of the cam 30. Thus, the props 10, 11, 12 and 13 are forcibly retracted, during which process pressurised hydraulic fluid flows from the working chambers 15 of the props 10 and 11 to the return line R via the lines 45 and 43, the servo-valve 36, the line 41 and the control valve 17. At the same time, pressurised hydraulic fluid flows from the working chambers 15 of the props 12 and 13 to the return line R via the lines 46 and 44, the servo-valve 35, the line 42 and the control valve 18. The servo-valves 35 and 36 are open at this stage, since, when the valve 25 is open, pressurised hydraulic fluid acts on their control pistons 37 via the control line 34.
When the props 10, 11, 12 and 13 have been retracted by the desired amount, the slide 28 of the valve 25 moves off the raised portion 31 of the cam 30, along the inclined portion 32a and into engagement with the recessed portion 32. At this point, the valve 25 closes under the action of the spring 26 so that the flow of pressurised hydraulic fluid to the working chambers 14 of the props 10, 11, 12 and 13 is cut off. At the same time, the control line 34 is depressurised so that the control pistons 37 of the servo-valves 35 and 36 are relieved of pressure and the servo-valves are closed under the action of their springs 38. The retraction of the props 10, 11, 12 and 13 is, therefore, terminated in a positive manner, the position at which this occurs being easily predetermined by suitable positioning of the valve 25 and the cam 30.
After the valve 25 has been closed, the props 10, 11, 12 and 13 can be retracted further, in the event of an overload, since their working chambers 15 are connected to the return line R via the pressure-relief valves 47 and 48. This prevents an overload on the roof cap causing damage to the roof support unit. Moreover, there is little danger to personnel since, in the event of such an overload, the props 10, 11, 12 and 13 are retracted very slowly.
In order to extend the props 10, 11, 12 and 13, after advance of the roof support unit, the control valves 17, 18 and 19 are manually actuated so that the lines 41 and 42 are connected to the pressure line P, and the line 24 is connected to the return line R. Pressurised hydraulic fluid acting on the closure members 39 of the servo-valves 35 and 36, via the lines 41 and 42, opens these valves so that the working chambers 15 of the props 10, 11, 12 and 13 are pressurised. As the props 10, 11, 12 and 13 are extended, hydraulic fluid flows from their working chambers 14 to the return line R via the line 24 and the open valves 25 and 19, the valve 25 being opened at the start of the prop extension process by the co-operation of its slide 28 with the raised portion 31 of the cam 30.
The particular function of the non-return valve 33 is to enable the props 10, 11, 12 and 13 to be retracted beyond the predetermined limit set by the valve 25, in the event of an overload. Thus, when the pressure-relief valves 47 and 48 open, fluid can flow back into the working chambers 14 of the props 10, 11, 12 and 13 via the line 24 and the non-return valve 33. | A hydraulic control system is provided for a roof support unit of an underground mining installation. The roof support unit is provided with a roof cap supported by hydraulic props. The control system comprises a valve for controlling the supply of pressurized hydraulic fluid to the props, and an actuator for closing the valve when the props have been retracted by a predetermined amount. | 4 |
FIELD OF THE INVENTION
[0001] This invention is related to the field of switching of electrical signals, specifically, signals ranging from DC to the gigahertz range, and, in particular, to improvements to a modular switching apparatus.
BACKGROUND OF THE INVENTION
[0002] The state of the art in the switching of electrical signals, and in particular, signals in the RF frequency range, is currently a modular, programmable switch of the type disclosed in U.S. Pat. No. 5,481,073 (Singer, et al.), which is incorporated herein by reference. This switch is modular, in that it is built from a plurality of identical switching modules, typically having a plurality of inputs/outputs which can be programmatically switched to a single input/output. By physically arranging the modules in a matrix fashion, that is, a plurality of modules stacked in a side-by-side fashion, with a second tiered plurality of modules, also stacked in a side-by-side fashion, a switch having an arbitrary number of inputs and an arbitrary number of outputs can be constructed, with any input being able to be switched to any output, in a single sub-system. Sub-systems can be cabled together to form larger switches.
[0003] While the switch disclosed in Singer represented an advancement in the state of the art in switch design, several drawbacks have been identified and several improvements addressing those drawbacks are disclosed herein.
[0004] First, the construction of the switch disclosed in Singer is complicated in that, after the switch matrix is placed in an enclosure, it may be necessary to remove and/or disassemble the entire assembly of modules in order to remove a single module. It is also necessary to use cabling if it is desired to have the input and output connectors of the switch matrix in the same plane, such as the rear panel of a chassis. This makes the switch labor-intensive to construct and precludes repair of failed modules in the field. Additionally, it is impossible for an end user to upgrade existing switches (i.e., from 4×4 to 8×8 or 1 6×16) by adding or replacing modules in the field. Thus, in the event a single module fails in the field, an end user will have to send the entire unit in to the manufacturer for repair or upgrade. Therefore, it is a goal of the improved switch to provide the capability of repair and upgrade of the switch in the field, thereby eliminating the need to take the unit out of service for extended periods of time for shipment to and from the factory for repair.
[0005] Second, the current switches are physically large in size. Customers typically mount the switches in 19″ racks of the type used for mounting electrical equipment, with a switch chassis having a 3U form factor. Often, rack space may be limited. Current state of the art switches can fit a 16×16 switch in a 3U chassis, with larger switches requiring multiple 3 U chassis with inter-chassis cabling to accomplish the necessary switching. For example, a 32×32 switch requires four 16×16 switch modules, two 16×4 signal distribution modules, two 4×16 output switch modules, and takes 24U of rack space. The number of chassis required increases by the square of the size increase. Doubling the size of a matrix requires four times as many switch chassis along with additional support chassis. Therefore, it would be desirable to increase the number of inputs and outputs available in a single chassis, and for this chassis to be as small as possible.
BRIEF SUMMARY OF THE INVENTION
[0006] The next generation modular switch has design enhancements which remedy the deficiencies in the current state of the art modular switch. The switch consists of a backplane into which input and output boards are plugged, as well as boards which bridge the input and output boards. This modular design eliminates internal cabling and the layout of the backplane allows the removal and replacement of all boards without disturbing other boards in the system, allowing the hot swappable, in field servicing of the switches. Initial assembly of the units is also greatly simplified, representing a savings in labor costs to assemble the units. Further, the next generation switch disclosed herein also has a high level of redundancy, allowing re-routing of connections in the event of a failure of one or more components, and the capability of self-diagnosis of faulty boards. The new modular design also provides a savings in physical space requirements, allowing a 32×32 switch in a 6U chassis form factor.
[0007] The preferred embodiment of the switch, having 32 inputs and 32 outputs (i.e., 32×32), consists of 8 input cards, each having 4 inputs, 8 output cards, each having 4 outputs, and 4 bridge cards bridging the input and output cards. However, varying configurations are possible. In a 6U chassis, configurations from 4×4 to 32×32 are possible. Configurations from 36×36 to 1024×1024 or larger are possible, but require multiple 6U chassis.
[0008] The input cards each have four inputs connected via the backplane to connectors on the rear of the chassis. For signals in the RF range, F, BNC, SMA or N style connectors are typically used, but the chassis may be configured with any type of connectors. Additionally, each input and output may be configured to have a 50 Ω or 75 Ω impedance. The input cards also each have 8 outputs and integrated splitters, so each input card is in actuality, a complete 4×8 matrix. Likewise, the output cards each have four outputs connected to the rear of the chassis via the backplane, 8 inputs and integrated splitters, so each output card is a complete 8×4 matrix.
[0009] The input and output cards are bridged by 8×8 switching matrices, thereby allowing any input to be routed to any output. In the preferred embodiment, each bridging card with have two 8×8 switching matrices. In a full-blown, 32×32 implementation, there are eight 8×8 switching matrices, with each of the 8 outputs of each input card being connected to an input on a different 8×8 switching matrix, such that each 8×8 matrix receives a signal from all input cards. Likewise, each of the 8 inputs of the output cards are connected to an output on a different 8×8 matrix, such that each 8×8 matrix supplies a signal to all output cards.
[0010] The backplane of the switch is laid out in a unique manner such as to minimize trace length, and thereby minimize signal loss as the signals are routed from the inputs to the outputs. The switch is also configured such that all components (i.e., all input and output cards, as well as the bridging cards, are accessible from the front of the unit and are hot-swappable without the need to disconnect cables or disassemble the units. All cards simply plug into the backplane utilizing standard off the shelf connecting hardware and hardware to secure the cards in place within the chassis. Input and output cards are also keyed to prevent their insertion into the wrong slots.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a logical diagram showing connections between input, output and bridge cards as well as a connection to the unit controller.
[0012] FIG. 2 shows a layout of the connectors for the input cards, the output cards and the bridge cards on the backplane.
[0013] FIG. 3 shows one layer of the backplane having holes cut therein to enhance air flow.
[0014] FIG. 4 is a upper level architecture diagram of an input and output card.
[0015] FIG. 5 is a upper level architecture of a circuit that could be used for self diagnostics.
[0016] FIG. 6 is an overall architecture diagram of the system.
[0017] FIG. 7 shows a front of the cabinet of the switches showing the layout of the input cards, the output cards, power supplies and bridge cards.
[0018] FIG. 8 is a top view of the switch showing the layout of the backplane, the input, the output and power cards.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] The switch of the current invention solves problems with backplane complexity, number of boards, space required and internal cabling complexity by using a different type of matrix architecture than is known in the prior art in this area. The architecture, known as a Clos or 3-stage matrix, is non-standard in the RF switching art, but is known in the prior art in other segments of the electronics industry. The Clos architecture builds a large matrix from smaller submatrices in a multilayer format.
[0020] In the preferred embodiment of the invention, as shown in FIG. 1 , there are eight input cards, each having a 4×8 matrix, four bridge cards, each having two 8×8 matrices and eight output cards, each having an 8×4 matrix, with standard splitter switch architecture. The eight input cards, four bridge cards and eight output cards are arranged in a three stage Clos matrix architecture to form a 32×32 switching matrix. The architecture requires only 128 connections between cards as opposed to the 1024 connections required if building a matrix with a standard single stage matrix architecture. Because all cards plug into a common backplane, all connections to the cards are handled by on-board traces rather than by actual cables, as was the case in the prior art. The reduced number of connections greatly decreases the complexity and the number of connectors required, which also lowers the cost to manufacture.
[0021] Referring to FIG. 1 , input matrices 101 ( a ) through 101 ( h ) are shown on the left hand side thereof, each having four inputs and eight outputs. The inputs to these cards are connected either directly or through the backplane via RF signal cables or a PCB to standard connectors on the back of the chassis of the unit, to a standard connector, typically either an F connector or a BNC connector, although any type of standard or non-standard connector can be used. The outputs of matrices 101 ( a ) through 101 ( h ) are connected to the inputs of bridge matrices 103 ( a ) through 103 ( h ) in the manner shown. That is, output 1 of matrix 101 ( a ) is connected to input 1 of bridge matrix 103 ( a ). Output 2 of matrix 101 ( a ) is connected to input 1 of bridge matrix 103 ( b ), and so on as shown. The outputs of bridge matrices 103 ( a ) to 103 ( h ) are connected in a similar fashion to the inputs of output matrices 102 ( a ) through 102 ( h ). Output matrices 102 ( a ) through 102 ( h ) each have four outputs which are connected to the back of the chassis of the unit. Thus, it is possible to route the signals from any input on any of input cards 101 ( a ) to any of output cards 102 ( a ) through 102 ( h ) via a plurality of different routes such that if one route is not available because of a bad card, other routes may be available. The 3-stage architecture having eight 4×8 input cards and eight 8×4 output cards bridged by eight 8×8 matrices, provides a minimum of eight paths from any given input to any given output.
[0022] FIG. 4 shows the architecture of the cards carrying the input and output matrices. They comprise switching circuitry 202 which is controlled by microcontroller 200 . With respect to the input matrices, microcontroller 200 is able to cause any of the four inputs to switching circuitry 202 be routed to any of the eight outputs from switching circuitry 202 . Note that FIG. 4 shows an input matrix card, however, the output matrix cards are identical in architecture, with the difference being that the output matrices have eight inputs and four outputs instead of the four inputs and eight outputs.
[0023] The cards carrying bridge matrices 103 ( a ) through 103 ( h ) are also similar in design, however, having eight inputs and eight outputs controlled by a microcontroller 200 . Additionally, bridging matrices 103 ( a ) through 103 ( h ) are arranged two per physical card, to facilitate the arrangement of the cards within the chassis of the unit and the to simplify the layout of backplane 110 .
[0024] Switch controller 118 shown on FIG. 1 is connected via a clock/data bus 111 to the microcontroller 200 on each of the input cards 101 ( a ) through 101 ( h ), bridge cards 103 ( a ) through 103 ( h ) and output cards 102 ( a ) through 102 ( h ). Switch controller 110 is able to accept commands, preferably via an RS-232 or RS-485 connection, from another device. The main commands consist of a source and a destination, indicating which of 32 inputs should be connected to which of the 32 outputs. Switch controller 118 is then able to send commands to configure individual microcontrollers on individual input cards 101 ( a ) through 101 ( h ), bridge cards 103 ( a ) through 103 ( h ) and output cards 102 ( a ) through 102 ( h ). For example, to route a signal from input 6 to output 24 it may be possible to use any one of eight different routes through the switch. First it will be necessary to configure input card 101 ( b ) into which input 6 is routed to route input 6 to one of eight outputs on input card 101 ( a ), thereby routing the signal to one of bridge cards 103 ( a ) through 103 ( h ). Switch controller 110 then configures the particular bridge card through which the signal is routed to route the signal from whatever input it is being received on to output 6 , which will route the card to output card 102 ( f ). Switch controller 110 then instructs the microcontroller 200 on output card 102 ( f ) to route the signal from whatever input it is being received on to output 24 . Note that if any one of bridge cards 103 ( a ) through 103 ( h ) is defective in any manner, the signal may be routed through any of the other bridge cards. Likewise, any input 1 - 32 can be routed to any output 1 - 32 . Therefore, if a bad circuit exists on one of input cards 101 ( a ) through 101 ( h ) or any of output cards 102 ( a ) through 102 ( h ), the signal can be rerouted by manually moving the cables to another input or another output and instructing switch controller 110 to route the signal from the particular input chosen to the particular output chosen.
[0025] FIG. 1 also shows system controller 120 which is responsible for communicating with switch controller 110 . System controller 120 serves two functions. First, a user interface is provided which is available to a PC connected via any known means to the system controller 120 such as by internet connection or serial connection. In addition, system controller 120 sends commands to the switch controller 118 instructing it to route various inputs to various outputs. Referring to FIG. 6 , which shows an architecture wherein multiple switches are being used in conjunction with each other to provide a larger matrix, such as a 256×256 matrix, system controller 120 can be instructed to route a signal from an input on one switch unit to the output on another switch unit and will send the appropriate commands to the switch controller 118 on each individual switch unit to affect the routing of the signal.
[0026] In one novel aspect of the invention, the input, bridge and output cards are arranged to be plugged into backplane 10 to eliminate internal cabling therebetween. The layout of the backplane is shown in FIG. 2 . To minimize signal trace length on the board and the length of cables used to connect the inputs and outputs to the to the connectors on the back of the chassis, input cards are mounted in connectors 114 and output cards are mounted in connectors 116 in an alternating fashion. This also minimizes the length of cables used to connect to the connectors on the back of the chassis of the unit. Connectors 112 are capable of accepting four bridge cards which, in the preferred embodiment of the invention, each have two 8×8 switching matrices thereon. Connectors 113 on either side of the array of input and output connectors serve as connectors for power supplies 104 and connectors 115 shown on the bottom of backplane 110 serve as a connector for a card which contains switch controller 118 .
[0027] One difficulty with the layout of the backplane card 110 shown in FIG. 2 is that vertical air flow necessary to cool the input and output cards is restricted by the presence of the bridge cards, which plug into connectors 112 in a horizontal manner. Therefore, the backplane is configured as shown in FIG. 3 with holes 120 along the top of the card, holes 121 along the bottom of the card, holes 122 in between the input and output cards and holes 123 on either side adjacent to power supplies 104 . These openings in the card allow the flow of air therethrough from a fan unit 120 mounted in the rear of the chassis of the unit to cool all of the cards. The switching traces are routed around the openings in the card.
[0028] In another novel aspect of the invention, it is possible to provide self-diagnostic circuitry as shown in FIG. 5 , on each of the input, bridge, and output cards to determine if individual inputs and outputs of each card are operating in the proper manner. To perform the diagnosis, tap 300 taps into the signal present on a particular input or output line and routes the signal through an RF signal strength indicator 302 which provides an analog indicator of the signal strength. This is converted to digital signal level information by an A/D converter 304 and is then fed to on-board microcontroller 200 . Microcontroller 200 compares the signal strength at an output to the original signal at an input and indicates whether or not the strength of the two signals are within acceptable boundaries. If not, an error may be indicated to switch controller 118 through the clock/data bus 111 . It is also possible to provide a similar circuit on the inputs and outputs that are routed to the back of the switch unit. This allows diagnosis of problems with individual inputs and outputs at the rear of the unit that allow diagnosis down to the board and/or a specific input or output level. Additionally, the presence of attenuator 306 on the input or output allows to the ability of the switch to adjust the signal level of the input or output for purposes of improving channel-to-channel isolation and matching the signal levels required by other equipment.
[0029] FIG. 7 shows a front view of the preferred embodiment of the switch showing the layout thereof. Output cards 102 ( a ) through 102 ( h ) and inputs cards 101 ( a ) through 101 ( h ) are arranged in an interlaced manner across the middle of the unit, with power supplies 104 located on either side thereof. Bridge cards 110 ( a ) through 110 ( d ) are shown with two at the top of the input and output cards and two at the bottom thereof. Note that this architecture also allows the backplane of the unit to be split in half for easier manufacture, because half of the input and output signals are routed to the upper bridge cards, and half are routed to the lower bridge cards. Switch controller 118 is shown in the lower left hand corner of the unit and blocks 109 represent options which may be installed into the system. The top view of the switch is shown in FIG. 8 wherein power supplies 104 and inputs and outputs 102 ( a ) through 102 ( h ) and 101 ( a ) through 101 ( h ), respectively, are shown connected to backplane 110 . Fan unit 120 as shown in the rear of backplane 110 and is capable of drawing air through the holes 120 , 121 , 122 and 123 defined by backplane 110 .
[0030] In the preferred embodiment of the invention, the switch unit itself contains 32 inputs and 32 outputs, however there is no reason why any configuration, typically in groups of four inputs and outputs could not be configured. In other words, it is not necessary that the entire chassis be filled with cards if a matrix smaller than 32×32 is required. It may also be possible and is contemplated to be within the scope of this invention to create larger input and output cards and larger bridge cards to create a larger overall matrix within one chassis or several sub-chassis. It is also possible to combine multiple 32×32 units to create the a larger matrix, for example, a 256×256 matrix or any size in between 32×32, by providing cable connections between the boxes and by utilizing system controller 120 to control the routing of the signals between the boxes.
[0031] A further advantage of the layout and architecture of the switch is that defective boards can be hot swapped for replacement or upgrade. In one embodiment of the invention, the unit is capable of telling the operator that board needs to be swapped and, in addition may also tell the operator which input or output of which board is nonfunctional, if equipped with the self-diagnostic circuitry shown in FIG. 5 . The system is also capable of automatically rerouting signals between inputs and outputs to compensate for bad routes until a defective board can be swapped. If one of bridge cards 103 ( a ) through 103 ( h ) is dysfunctional, it would be possible to reroute the signal in a manner that is invisible to the user, i.e., this would not require the switching of cables from an input on the back of the unit to an output on the back of the unit, however, the manual switching of cables may be unavoidable if the defect occurs in one of input cards 101 ( a ) through 101 ( h ) or output cards 102 ( a ) through 102 ( h ).
[0032] The bridge cards connect to the backplane at right angles to the input and output cards, such that a bridge card will span all the input and output cards. This arrangement, along with the alternating arrangement of the input and output cards and arranging the bridge cards above and below the input and output cards provides an optimally efficient routing of signals on backplane 110 and reduces the number of layers required in the backplane PBC and thus makes it easier to manufacture. Additionally, the shortest possible routings on the backplane PCB 110 minimize signal loss between matrices. In addition, all input, bridge and output cards are accessible from the front of the unit, which allows customers to maintain or expand the switch unit with ease and is a novel point which provides a major advantage over competing products.
[0033] The illustrations, layouts, materials, and dimensions used herein are exemplary in nature only and are not meant to limit the scope of the invention, which is embodied in the claims which follow. | A programmable switch for broadband signals having a modular design in which input cards, bridging cards and output cards are interconnected through a common backplane to form a switching matrix having a Clos architecture. All connections between cards are made through the backplane to decrease the complexity of the switch and are arranged to minimize the length of signal traces to minimize signal loss. The backplane is unique in that it is configured with venting holes to facilitate the flow of cooling air therethrough. All modules, including input cards, output cards and bridge cards are hot swappable. | 7 |
REFERENCE TO RELATED APPLICATIONS
The present invention is a divisional application of U.S. patent application Ser. No. 10/685,215, filed Oct. 14, 2003.
BACKGROUND
This invention relates to vibration isolators, and more particularly, to an isolation system for minimizing in-plane vibrations produced in a rotating system of a rotary-wing aircraft, and still more particularly, to an isolation system that minimizes system weight, aerodynamic drag, and complexity while concomitantly providing active control and adjustment during operation for optimal efficacy across a wide spectrum of operating speeds.
Vibration isolation or absorption is oftentimes desirable for nulling or canceling vibrations associated with a rotating system. Such vibrations, when left unattenuated or unabated, may lead to structural fatigue and premature failure of system components. Furthermore, inasmuch as such vibrations may be transmitted through adjacent support structure to, for example, an aircraft avionics bay, areas occupied by passengers, or other components and cabin area remote from the source of the vibration which may also be subject to these same potentially damaging or disturbing vibrations (albeit perhaps lower in amplitude due to energy absorption by the interconnecting structure). Consequently, it is most desirable to isolate or absorb these vibrations at or near the source of the vibration in the rotating system
One application which best exemplifies the need for and advantages derived from vibration isolation/absorption devices is the main torque driving hub of a helicopter rotor system. Typically, the main rotor of a helicopter, which comprises a central torque drive hub member for driving a plurality of lift producing rotor blades, is subject to a variety of aerodynamic and gyroscopic loads. For example, as each rotor blade advances or retreats relative to the freestream airflow, it experiences a sharp rise and fall of in-plane aerodynamic drag. Furthermore, as the tip of each rotor blade advances with each revolution of the rotor system, the relative velocity of the blade tip approaches supersonic Mach numbers. As such, large variations occur in the various coefficients which define blade performance (e.g., moment, lift and drag coefficients). Moreover, gyroscopic and Coriolus forces are generated causing the blades to “lead” or “lag” depending upon cyclic control inputs to the rotor system. All of the above generate substantial in-plane and out-of-plane vibrations which, if not suppressed, isolated or otherwise abated, are transmitted to the cockpit and cabin, typically through the mounting feet of the helicopter main rotor gearbox.
Various vibration isolation systems have been devised to counteract/oppose and minimize these in-plane and out-of-plane vibrations. Mast-mounted vibration isolators suppress or isolate in-plane vibrations at a location proximal to the source of such in-plane vibrations whereas transmission, cabin or cockpit absorbers dampen or absorb out-of-plane vibrations at a location remotely disposed from the source. Inasmuch as the present invention relates to the isolation of in-plane vibrations, only devices designed to counteract/oppose such vibrations will be discussed herein.
Some mast-mounted vibration isolators have a plurality of resilient arms (i.e., springs) extending in a spaced-apart spiral pattern between a hub attachment fitting and a ring-shaped inertial mass. Several pairs of spiral springs (i.e., four upper and four lower springs) are mounted to and equiangularly arranged with respect to both the hub attachment fitting and the inertial mass so as to produce substantially symmetric spring stiffness in an in-plane direction. The spring-mass system, i.e., spiral springs in combination with the ring-shaped mass, is tuned in the non-rotating system to a frequency equal to N*rotor RPM (e.g., 4 P for a four-bladed rotor) at normal operating speed, so that in the rotating system it will respond to both N+1 and N−1 frequency vibrations (i.e., 3 P and 5 P for a four-bladed rotor). N is the number of rotor blades.
While these spiral spring arrangements produce a relatively small width dimension (i.e., the spiraling of the springs increases the effective spring rate), the height dimension of each vibration isolator is increased to react out-of-plane loads via the upper and lower pairs of spiral springs. This increased profile dimension increases the profile area, and consequently the profile drag produced by the isolator. The spiral springs must be manufactured to precise tolerances to obtain the relatively exact spring rates necessary for efficient operation such that manufacturing costs may be increased. Furthermore, these vibration isolators are passive devices which are tuned to a predetermined in-plane frequency. That is, the vibration isolators cannot be adjusted in-flight or during operation to isolate in-plane loads which may vary in frequency depending upon the specific operating regime.
Another general configuration of isolator known as a “bifilar” are mast-mounted vibration isolators having a hub attachment fitting connected to and driven by the helicopter rotorshaft, a plurality of radial arms projecting outwardly from the fitting and a mass coupled to the end of each arm via a rolling pin arrangement. That is, a pin rolls within a cycloidally shaped bushing thereby permitting edgewise motion of each mass relative to its respective arm. The geometry of the pin arrangement in combination with the centrifugal forces acting on the mass (imposed by rotation of the bifilar) results in an edgewise anti-vibration force at a 4 per revolution frequency which is out-of-phase with the large 4 per revolution (or “4 P” as it is commonly referred to as helicopter art) in-plane vibrations of the rotor hub for a 4 bladed helicopter. The frequency of 4 P is the frequency as observed in a non-rotating reference system.
More specifically, pairs of opposed masses act in unison to produce forces which counteract forces active on the rotor hub. In FIG. 1 , a schematic of a pair of bifilar masses, at one instant in time, are depicted to illustrate the physics of the device. Therein, the masses MI, MII are disposed at their extreme edgewise position within each of the respective cycloidal bushings BI, BII. The masses MI, MII produce maximum force vectors F/2, which produce a resultant vector F at the center, and coincident with the rotational axis, of the rotating system. The combined or resultant force vector F is equal and opposite to the maximum vibratory load vector P active on the rotor at the same instant of time. This condition, when the bifilar produces an equal and opposite force F that opposes the rotor load P, reflects ideal operation of the bifilar. Excessive bifilar damping or manufacturing imperfections will cause the bifilar output force F to differ from the disturbing force P produced by the rotor either in magnitude or phase best suited to nullify the rotor loads. This condition may cause unwanted fuselage vibration. It will also be appreciated that for the masses to produce the necessary shear forces to react the in-plane vibratory loads of the rotor system, counteracting bending moments are also produced. These force couples impose large edgewise bending loads in the radial arms, and, consequently, the geometry thereof must produce the necessary stiffness (EI) at the root end of the arms. As such, these increased stiffness requirements require the relatively large and heavy bifilar arms.
While the bifilar system has proven effective and reliable, the weight of the system, nearly 210 lbs, is detrimental to the overall lifting capacity of the helicopter. To appreciate the significance of the increased weight, it has been estimated that for each pound of additional weight, direct operating cost of the helicopter may increase by approximately $10,000.
Furthermore, the pin mount for coupling each mass to its respective radial arm routinely and regularly wear, thus requiring frequent removal and replacement of the cyclical bushings. This increases the Direct Maintenance Costs (DMC) for operating the helicopter, which contributes, to the fiscal burdens of the bifilar system and the helicopter.
Therefore, a need exists for an isolation system to reduce vibrations in a rotating system that isolates a wide spectrum of vibratory loads; especially large amplitude loads, minimizes system weight, reduces aerodynamic drag and reduces DMC.
SUMMARY
The present invention provides a vibration isolation system which is controllable for varying the range of isolation frequencies which absorbs large amplitude vibrations while minimizing system weight.
The vibration isolation system employs readily manufactured components which is insensitive to damping and manufacturing imperfections.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete understanding of the present invention and the attendant features and advantages thereof may be had by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:
FIG. 1 is a schematic of a prior art bifilar isolation device for illustrating certain physical characteristics thereof.
FIG. 2 is a side sectional view of a helicopter main rotor, including a main rotor shaft having an isolation system according to the present invention mounted to the upper mast or shaft extension member of the rotor.
FIGS. 3 a - 3 c depict schematic views of various operating conditions of the inventive isolation system.
FIG. 4 is a side sectional view of one embodiment of the isolation device.
DETAILED DESCRIPTION
The isolation system of the present invention is described in the context of a helicopter rotor system, such as that employed in an Army BLACK HAWK helicopter produced by Sikorsky Aircraft Corporation. One skilled in the art, however, will appreciate that the present invention has utility in any rotating system which produces vibratory loads (noise). The invention is especially useful in rotating systems that produce large vibratory loads that vary depending upon different operating regimes or variable operating speeds.
Referring to FIG. 2 , the vibration isolation system 10 is disposed in combination with a rotary-wing aircraft main rotor system 2 having a main rotor shaft 4 (rotating system member) that is driven about a rotational axis 6 by a torque driving transmission 8 . In the described embodiment, the rotor system 2 includes a hub 12 having four radial arms that mount to and drive each rotor blade 16 . The vibration isolation system 10 is mounted to a flanged end 13 of the main rotor shaft 4 through a hub attachment fitting 18 . Vibratory forces active on the main rotor system 2 are generated by a variety of factors, although the dominant vibrations originate from aerodynamic and/or gyroscopic forces generated by each rotor blade 16 . A four bladed rotor system produces 3 P vibratory loads, i.e., in a single revolution, the magnitude of the load vector varies from a minimum to a maximum value three times in the rotating frame of reference. This resolves into 4 P vibration in the non-rotating frame of reference due to the addition of the 1 P rotor rotational speed. While a variety of factors influence the vibratory spectrum of a rotor system, such 4 P vibrations are generally a result of each rotor blade experiencing maximum lift when advancing and minimum lift when retreating.
Referring to FIGS. 2 and 4 , the vibration isolation system 10 includes two, essentially coplanar, masses M 1 , M 2 , a drive system 30 for driving the masses M 1 , M 2 about the rotational axis 6 of the main rotor shaft 4 , a control system 40 for issuing control signals to the drive system 30 to control the rotational speed and relative angular position of the masses M 1 , M 2 and a power source 50 for energizing the drive system 30 and control system 40 .
The masses M 1 , M 2 are (i) disposed at a predetermined distance R from the main rotor shaft axis 6 ; (ii) driven in the same or opposing rotational direction as the main rotor shaft axis 6 ; and (iii) driven at a rotational speed at least 3 P greater than the rotational speed 1 P of the rotor shaft 4 . In one embodiment, the drive system 30 includes a pair of electric motors 34 a , 34 b for driving each of the masses M 1 , M 2 through a relatively small diameter, constant cross-section radial arm 36 (shown schematically in FIGS. 3 a - 3 c ). Moreover, the electric motors 34 a , 34 b are independent of each other, e.g., may be driven at different rotational speeds to enable variation of the isolation force magnitude and phase.
As shown in FIG. 4 , the control system 40 requires a speed sensor 42 for issuing signals 42 s indicative of the rotational speed 1 P of the rotor shaft 4 , and a signal processing and amplifier 44 , responsive to the speed signals 42 s , to issue control signals 44 s to the drive system 30 indicative of the rotational velocity and relative angular position of each of the masses M 1 , M 2 . While the speed sensor 42 may be a dedicated unit for sensing rotor speed, the same information may be obtained from a transmission alternator or generator 50 which turns at a predefined speed multiple relative to the rotor speed. The alternator or generator 50 supplies power to the controller-amplifier 44 through the slip ring 54 . Hence, the control system 40 may use voltage phase information from such devices to issue the appropriate control signals to the drive system 30 .
While the isolation system 10 may employ a control system 40 having a predefined schedule or model of the vibrations, e.g., at prescribed rotor speeds, another embodiment may also employ a vibration sensing device or system. As such, the control system 40 includes one or more vibration feedback sensors 51 for issuing vibration signals 51 s indicative of the vibrations (e.g., amplitude, frequency and phase) of the helicopter rotor hub 12 . The control system 40 , therefore, samples vibration levels at predefined intervals or rates to identify a trend-positive (lower vibration levels) or negative (larger vibration levels). Accordingly, as vibration levels change, the control system 40 issues modified signals 44 s to the drive system 30 until an optimum combination of rotational speed, force magnitude and phase are achieved.
The isolation system 10 may be powered by any of a variety of known methods, especially methods which may require transmission from a stationary to a rotating reference field. In the described embodiment shown in FIG. 4 the drive system 30 and control system 40 , respectively, are powered by a 15 kVa generator 50 which provides a 115 volt potential at 400 Hz and with 3 phases (typical AC power for helicopters). Power is transferred from the stationary system to the rotating system via a conventional cylindrical slip ring 54 . Only a small amount of additional weight is required inasmuch as the slip ring 54 is pre-existing and used for powering other systems e.g., rotor blade de-ice system. This slip ring may also be used to communicate the control signals 42 s to the drive system 30 when the control system 40 is mounted in the fuselage rather than on the rotor system 2 .
In operation, the masses M 1 , M 2 (shown in FIGS. 3 a - 3 c ) are driven by the drive system 30 at a rotational speed greater than the rotational speed of the rotating system and appropriately positioned to yield a load vector P 10 which is equal and opposite to the load vector P 2 produced by the rotor system 2 . This counteracting load vector P 10 can be viewed as a vector which attempts to cancel or null the displacement of the rotor shaft 4 . In the described embodiment, the masses turn at a rotational speed.
Inasmuch as the drive system 30 is mounted directly to the rotating shaft 4 of the rotor system 2 , the drive system 30 need only drive the masses M 1 , M 2 three additional revolution per cycle (for each revolution of the rotor system) to achieve the desired 4 P frequency. That is, since the masses M 1 , M 2 are, in a rotating reference system, driven at one revolution per cycle by the rotor system 2 itself, the drive means 30 need only augment the rotational speed by the difference (4 P−1 P) to achieve the necessary 4 P in the stationary reference system.
FIGS. 3 a - 3 c depict various operating positions of the masses M 1 , M 2 to emphasize the function and versatility of the isolation system 10 .
In FIG. 3 a , the masses M 1 , M 2 are essentially coincident and act in unison to produce a maximum force vector P 10 MAX.
In FIG. 3 b , the masses M 1 , M 2 define a right angle (90 degrees) therebetween thereby producing a force vector P 10 MAX/(sqrt (2)) that is a fraction of the magnitude of the maximum force vector.
In FIG. 3 c , the masses M 1 , M 2 define a straight angle (180 degrees) and are essentially opposing to cancel the vectors produced by each of the masses M 1 , M 2 independently or individually.
In FIG. 4 , the controller 40 issues signals to the drive system 30 to (a) drive the masses M 1 , M 2 at a rotational speed greater than that of the rotating system and (b) produce a counteracting load of the correct magnitude and phase to efficiently isolate vibrations.
The ability to independently vary the relative angular position of the masses M 1 , M 2 is especially valuable in applications wherein the magnitude of the vibratory load active in/on the rotating system varies as a function of operating regime or operating speed. In a rotary-wing aircraft, for example, it is common to require the highest levels of vibration isolation in high speed forward flight i.e., where the rotor blades are experiencing the largest differential in aerodynamic loading from advancing to retreating sides of the rotor system. Consequently, it may be expected that the drive system 30 produce the maximum load vector P 10 MAX such as illustrated in FIG. 3 a . In yet another example, it is anticipated that the lowest levels of vibration isolation would occur in a loiter or hovering operating mode, where the rotor blades are exposed to the generally equivalent aerodynamic and gyroscopic affects. Consequently, it may be expected that the drive means 30 produce no or a minimum load vector P 10 MIN such as illustrated in FIG. 3 c.
Thus far, the discussion herein has concentrated on the rotational speed and angular position of the masses M 1 , M 2 to produce vibration isolation. While this feature of the invention is a primary aspect of the invention, the configuration of the inventive isolation system 10 produces counteracting load vectors P 10 which act though the rotational axis of the rotor shaft 4 . That is, the line of action of the load vector P 10 , whether the masses M 1 , M 2 are coincident or opposing, intersects the rotational axis and produces pure radial loads. As such, the radial arms of the isolation system 10 are principally loaded in tension rather than a combination of tensile and bending moment loads. A consequence of this loading condition is a reduction in system weight inasmuch as the radial arms 36 need not produce high edgewise strength to react bending moment loads.
Furthermore, tensile loading in the radial arms 36 enables the use of a constant-cross-section structure to react the centrifugal loads produced by each of the masses M 1 , M 2 . Moreover, directional strength materials (non-isotropic) may be employed such as unidirectional fiber reinforced composites. As a result, the isolation device may be produced using relatively low cost manufacturing techniques and materials. For example, cylindrical raw material stock, cut to the proper length, may be employed without secondary processing. Also, the use of unidirectional composites enables yet further weight reduction
Although the invention has been shown and described herein with respect to a certain detailed embodiment of a mast-mounted helicopter isolator, it will be understood by those skilled in the art that a variety of modifications and variations are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the present invention may be practiced otherwise than as specifically described hereinabove. | A method and device for reducing vibratory noise in a system with an integral rotating member includes independently operable drive systems for controlling the angular velocity of at least two independently rotatable masses. Control signals manipulate the drive system to rotate each mass at optimal speed, direction and phase to reduce noise induced in the system by the rotating member. | 5 |
BACKGROUND
1. Field of the Invention
The present invention relates, in general, to vehicle grille or brush guards.
2. Description of the Art
Vehicle grille or brush guards are typically formed of a tubular frame structure having horizontal slats and/or vertical posts mounted within an outer frame. The brush guard is mounted by means of brackets in front of the vehicle grille and headlights.
Typically, brush guards have been mounted over the top and front of the bumper and connected to the top or side of the vehicle frame rails or extend below the bumper to a connection with the bottom of the frame rails. Such mounting arrangements place a portion of the brush guard in front of the vehicle front bumper where it is in a position to contact an object during a front collision before the bumper engages the object.
However, the placement of a vehicle brush guard in front of the bumper raises a significant problem with respect to the on-board collision sensors which are designed for interaction with crush surfaces in the vehicle to activate a passenger restraint, such as an air bag, at the proper time during a front end collision so that the air bag inflates in sufficient time to absorb forward motion of the vehicle front seat occupant(s).
The conventional mounting of vehicle brush guards in front of the vehicle will cause the vehicle crush surfaces to begin their movement toward each other and result in an earlier engagement with and earlier triggering of the vehicle collision sensors which activate the air bag restraint slightly earlier than would be normal if the vehicle did not have a brush guard and the vehicle bumper itself, as it was originally designed, first contacted the object. An earlier than designed activation of the air bag during a front collision will cause the air bag to inflate earlier than normal such that the air bag itself would be starting to deflate when first contacted by a vehicle front seat occupant. This, of course, negates the restraint features provided by the air bag.
Thus, it would be desirable to provide a vehicle brush guard mountable in front of the vehicle grille which does not change the spatial relationship between the vehicle crush surfaces which trigger collision sensors used to activate a vehicle passenger restraint air bag in a front end collision.
SUMMARY
The present invention is a vehicle attachment is the form of a brush guard mountable on a vehicle in a position which does not change the vehicle front end collision sensor activation sequence during a front-end collision with the vehicle bumper. In one aspect, the vehicle attachment is a brush guard and a mounting member for mounting the brush guard to a vehicle frame where the front surface of the brush guard is disposed behind a front-most edge of the front vehicle bumper.
The brush guard, in an exemplary aspect, is constructed of spaced, joined members. Each of a pair of mounting members includes means for attaching the mounting members to the brush guard. Each mounting member includes a mounting surface or portion mountable between the bumper mounting bracket and the bumper frame rail mounting bracket of a vehicle. Each mounting member also has a crush surface which is designed to be positioned in the same spacial relationship from a vehicle mounted sensor activation crush surface as the original crush surface on the bumper mounting bracket.
In one aspect of the invention, a pair of brush guard mounting members are provided on the brush guard. Each one of the pair of brush guard mounting members has a first crush surface nominally spaced from a sensor crush surface at the first spacing.
In another aspect of the invention, outrigger support brackets are mounted between a laterally outboard position of the brush guard and the vehicle bumper. Preferably, the brush guard is releasably connected to the outrigger support bracket.
The brush guard mounting member, in one aspect, is movably mountable on the bumper mounting bracket. In another aspect, the brush guard mounting member is pivotal relative to the bumper mounting bracket under vehicle collision forces.
The mounting members provide a secure mount for a brush guard on a vehicle without requiring the brush guard to be attached to the bumper of the vehicle. More importantly, the mounting members mount the brush guard on a vehicle in a position above the top surface of the bumper so that the brush guard does not extend forwardly of the foremost surface of the bumper. This prevents the brush guard from interfering with the normal crush sequence of the bumper and collision sensors of the vehicle during a front end collision.
The crush surfaces formed on the brush guard mounting members act in the same fashion as similar crush surfaces normally found on the bumper mounting brackets to trigger or activate the vehicle collision sensors at the same time during a front collision as the bumper mounting brackets in a vehicle crush sequence for nominal operation of the inflatable passenger restraint air bags.
The present brush guard is easily attachable to existing vehicles despite the different vehicle bumper mounting configurations.
BRIEF DESCRIPTION OF THE DRAWING
The various features, advantages and other uses of the present invention will become more apparent by referring to the following detailed description and drawing in which:
FIG. 1 is a rear perspective view of a vehicle bumper showing a vehicle bumper mounting bracket;
FIG. 2 is a perspective view of a vehicle frame rail showing the bumper frame rail mounting bracket mounted thereon;
FIG. 3 is a bottom perspective view of a typical collision sensor and sensor mounting bracket;
FIG. 4 is a side elevational, partially cross-sectioned view showing the spatial relationships of the bumper mounting bracket, the bumper, the bumper frame rail mounting bracket, the frame rail, the collision sensor and the collision sensor mounting bracket in their normal mounted positions;
FIG. 5 is a front perspective view of a brush guard according to the present invention mounted on a vehicle in connection with the bumper and frame rail assemblies shown in FIGS. 2-4;
FIG. 6 is a perspective view of a driver side brush guard mounting bracket according to the present invention;
FIG. 7 is a perspective view showing a passenger side brush guard mounting bracket of the present invention depicted in its mounted position on the bumper mounting bracket attached to the vehicle bumper;
FIG. 8 is a perspective view showing the attachment of the vehicle brush guard to the brush guard mounting bracket shown in FIG. 7;
FIG. 9 is a side elevational view, partially cross-sectioned, depicting the spatial relationships of the vehicle brush guard mounting bracket, the bumper frame rail mounting bracket, the vehicle bumper and the crash sensor mounting bracket in their normal mounted position;
FIG. 10 is a perspective view showing an outrigger bracket according to one aspect of the invention connecting the side outboard portion of the vehicle brush guard to the vehicle bumper;
FIG. 11 is a perspective view of the outrigger mounting bracket shown in FIG. 10; and
FIG. 12 is a rear perspective view of the vehicle bumper showing the mounting of the outrigger mounting bracket to the bumper.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawing, and to FIGS. 1-4 in particular, there is depicted a typical bumper front fascia assembly for a vehicle. The bumper assembly includes a conventional bumper 10 which may be formed of any suitable material, such as metal, formed plastic, etc. As shown in FIGS. 1 and 4, the bumper 10 includes a top generally horizontally extending top wall 12 , a front, vertically extending wall 14 and a bottom, inward curved bottom wall 16 . A metal frame 18 is mounted on an inside surface of the bumper 10 and is joined to the bumper 10 by suitable fasteners, such as J-nuts 20 .
A bumper mounting bracket shown generally by reference number 26 is secured by fasteners 28 to the metal frame 18 . The bumper mounting bracket 26 , which may take any suitable shape, includes, by example, a raised center portion 30 having apertures which receive fasteners, such as bolts 32 , for attaching the bumper mounting bracket 26 to a bumper frame rail mounting bracket 34 shown in FIG. 2 .
The bumper frame rail mounting bracket 34 is of a generally U-shaped member having an end wall 36 and opposed side walls 38 , only one of which can be seen in FIG. 2 . The side walls 38 include an open ended aperture, such as a generally triangular aperture, which divides each side wall 38 into spaced leg portions as shown in FIGS. 2 and 4. The end wall 36 terminates short of the end of the side walls 38 to form an opening 40 in conjunction with the lower extended portions of the side walls 38 which enables the mounting bracket 34 to be disposed over a conventional tubular frame rail 42 and secured thereto by suitable fasteners, welds, etc. A pair of apertures 44 are formed in the bumper frame rail mounting bracket 34 and alignable with the apertures in the bumper mounting bracket 26 to receive the fasteners or bolts 32 to normally secure the bumper mounting bracket 26 to the bumper frame rail mounting bracket 34 and thereby attaching the vehicle bumper 10 to the vehicle frame rails 42 .
As shown in FIGS. 3 and 4, a conventional vehicle collision sensor depicted generally by reference number 50 is mounted on a sensor mounting bracket 52 to stationary vehicle structure. A crush surface 54 is formed at one end of the bracket 52 and adapted to engage a corresponding bumper crush surface 56 formed on the end of a tab extending from the center portion 30 of the bumper mounting bracket 26 as shown in FIG. 4 during a front collision. While in the normal mounting position of the bumper 10 relative to the frame rails 42 , opposed faces of the crush surfaces 54 and 56 are spaced apart. However, during a collision, once the bumper 10 becomes stationary upon engagement with an object, the momentum of the vehicle will cause the frame rails 42 to continue to move in a forward direction. After a predetermined amount of advance, the crush surface 54 will engage the crush surface 56 thereby causing movement or displacement of the sensor mounting bracket 52 . This movement is detected by the sensor 50 which can be any conventional collision sensor typically used with vehicle passenger restraint systems, such as air bags. Once this force or displacement is detected by the sensor 50 , the sensor 50 outputs a signal which activates the passenger restraint system, typically causing an air bag or bags in the front of the vehicle to inflate and restrain the forward movement of the front seat vehicle passengers.
Referring now to FIGS. 5-12, there is depicted a vehicle brush guard 60 mounted above the top wall or surface 12 of the bumper and in front of the grille and headlights of the vehicle. The brush guard 60 is in the form of a generally tubular frame formed of vertical and horizontal interconnected slats and posts. The brush guard 60 may take any suitable form.
Thus, for clarity and by way of example only, the brush guard 60 includes a center frame formed of a light bar 62 which is connected at opposite ends to a pair of generally planar vertical straps 64 . The light bar 62 functions as a support for mounting auxiliary headlights on the vehicle.
A pair of laterally extending frame assemblies extend from the vertical straps 64 and are formed of upper and lower tubular members 66 and 68 which are interconnected by a plurality of vertical posts 70 . Horizontal slats 72 extend between and are joined to the posts 70 .
A frame formed of opposed vertically extending side legs 74 and an upper center cross bar 76 extends from the lower tubular members 68 on either side of the center frame and through the upper tubular members 66 and 68 .
According to a unique feature of the present invention, a pair of brush guard mounting brackets 78 and 80 are provided for mounting the brush guard 60 to the vehicle at two locations. Two substantially mirror image brush guard mounting brackets 78 and 80 are provided as shown on FIGS. 6 and 7, respectively. As shown in FIG. 6 the first brush guard mounting bracket 78 , which will typically be mounted on the driver's side of the center line of the vehicle, includes a generally planar portion 84 having a pair of apertures 86 , preferably in the form of slots, formed therein for securing the bumper guard mounting bracket 78 to the bumper mounting bracket 26 by the bolts 32 . An extension or tab 88 extends from the planar portion 84 and lies in the same plane as the planar portion 84 .
A crush surface 90 is formed on the mounting bracket 78 . For the mounting bracket 78 , the crush surface 90 is unitarily formed as part of the planar portion 84 , but is bent out of the plane of the planar portion 84 by a first bend 92 . The crush surface 90 is formed as a planar surface extending from the bend 92 and is disposed generally parallel to, but offset from the planar portion 84 .
The length or extent of the bend 92 places the outer surface of the crush surface 90 at a distance from the outer surface of the planar portion 84 substantially equal to the thickness of the planar portion 84 . This enables the crush surface 90 to be in the same spatial position relative to the crush surface 54 as was the original crush surface 56 on the bumper mounting bracket 26 .
A second bend 94 at the other end of the crush surface 90 forms a planer upper surface 96 generally perpendicular to the planar portion 84 and the crush surface 90 . A dart 98 is formed through the second bend 94 for structural rigidity.
A flange 100 projects perpendicularly from one side of the upper surface 96 . The flange 100 includes a mounting aperture 102 , a clearance notch 104 and an open ended mounting slot 106 .
As shown in FIG. 7, the second brush guard mounting bracket 80 is similarly constructed and like components have been given the same reference number as the components of the first mounting bracket 78 described above and shown in FIG. 6 .
Thus, the second brush guard mounting bracket 80 includes the planar portion 84 with an extension or tab 88 projecting therefrom. A pair of mounting slots, not shown in FIG. 7, are formed in the planar portion 84 for receiving the mounting bolts. The first bend 92 is formed in the planar portion 84 and forms an outwardly projecting surface 91 which is offset, but parallel to the planar portion 84 . A second bend 94 forms an upper surface 96 perpendicular to the offset surface 91 . The flange 100 is formed along one side of the upper surface 96 and includes the mounting aperture 102 , the clearance notch 104 and the mounting slot 106 .
Due to the particular vehicle engine component configuration, the tab 88 , by example, rather than the surface 91 acts as the mating crush surface for the passenger side collision sensor mounting bracket.
As shown in FIGS. 6-9, both mounting brackets 78 or 80 are mountable with the planar portion 84 in registry with the center portion 30 of the bumper mounting bracket 26 . The apertures or slots 86 in each planar portion 84 are alignable with the apertures in the center portion 30 of the bumper mounting bracket 26 to receive the bolts 32 as described hereafter.
In this mounting position, the upper surface 96 of each mounting bracket 78 and 80 projects above and is spaced from the upper surface 12 of the vehicle bumper 10 . This places the flange 100 above the upper surface 12 of the bumper 10 as shown in FIGS. 8 and 9. Mounting bolts 110 extend through aligned apertures formed on the bottom of the vertical strap 64 of the brush guard 60 and the mounting aperture 102 and mounting slot 106 on the flange 100 to fixably secure the brush guard 60 to the first and second mounting brackets 78 and 80 without contact with the bumper 10 .
The open-ended mounting slot 106 enables the brush guard 60 to pivot and separate from the end of the flange 100 during a front end collision.
As shown in FIG. 9, the crush surface 90 on the first mounting bracket 78 , when the planar portion 84 of the mounting bracket 78 is disposed between and secured to the bumper mounting bracket 26 and the bumper frame rail bracket 34 , is spaced from the opposed crush surface 54 on the sensor mounting bracket 52 at the same position and at the same distance as was the original crush surface 56 which is removed from the bumper mounting bracket 26 so as to function in the same manner as the tab 56 during a front end collision to trigger the sensor 50 to activate the air bag at the proper time in the vehicle crush sequence.
Although not shown, the extension or tab 88 on the second mounting bracket 80 forms the crush surface for the mounting bracket 80 which is engagable with the crush surface on a passenger side sensor mounting bracket 52 . The tab 88 is located in the same spacial relationship from the crush surface on one end of the sensor mounting bracket 52 on the passenger side of the vehicle as was crush surface on the bumper mounting bracket 26 on the passenger side of the vehicle. It should be noted that the passenger side bumper mounting bracket 26 does not include the rearward extending tab forming the crush surface 56 on the driver side bumper mounting bracket 26 .
Referring now to FIGS. 10-12, there is depicted one of a pair of outriggers 120 which are used to releasable secure the outer ends of the brush guard 60 to the vehicle bumper 10 . The outriggers 120 are optional, but are preferred when the brush guard 10 extends a considerable length along the vehicle bumper 10 , such as shown in FIG. 5 . Of course, smaller length brush guards, such as those covering only the center grille of a vehicle, would not necessarily require the outriggers 120 .
Each outrigger 120 , by example only, is in the form of a bent or formed metallic strap having a first end portion 122 , an intermediate portion 124 extending angularly from the first end portion 122 , and a second end portion 126 extending angularly from the intermediate portion 124 , and generally perpendicular to the first end portion 122 . As shown in FIG. 12, the first end portion 122 of each outrigger 120 is disposed behind the inner edge of the top wall 12 of the vehicle bumper 10 and has a mounting aperture 128 alignable with an aperture in a bumper side stiffener strap 132 and receiving the same fastener 134 used to secure one end of the stiffener strap 132 to the metal frame 18 behind the bumper 10 .
The intermediate portion 124 of each outrigger 120 then extends angularly outward from the first end portion 122 to position the second end portion 126 generally parallel to the bottom surface to the bottom tubular member 68 on either side of the brush guard 60 . A fastener, such as a bolt 134 shown in FIG. 10, is mountable through a mounting slot 130 on the second end portion 126 of each outrigger 120 and the bottom tubular member 68 of the brush guard 60 . The mounting slot 130 enables the outrigger 120 to separate from the brush guard 60 during a collision.
In summary, the present invention is a unique vehicle attachment, such as a brush guard, mountable on a vehicle in a manner which does not alter the spatial relationship between the vehicle sensor activating crush surfaces. | A brush guard is attachable to a vehicle frame rail or a vehicle bumper mounting bracket by means of mounting members, each having a mounting surface mountable between the bumper mounting bracket and the bumper frame rail mounting bracket. Each mounting member includes a crush surface positioned in the same spatial relationship from a vehicle mounted sensor crush surface as the original crush surface of a bumper mounting bracket. The brush guard is mounted on the vehicle independent and free of the bumper and is disposed in a position so that the brush guard does not extend forwardly of the frontmost surface of the bumper. In one aspect, the mounting members are pivotally connected to the vehicle to allow pivotal movement of the brush guard during a front-end vehicle collision. A pair of optional outriggers are releasably secure to the outer lateral ends of the brush guard and the vehicle bumper. | 1 |
The present invention concerns a method and device for calibrating an optical pyrometer, and associated reference wafers. One of the applications of the present invention relates in particular to the calibration of pyrometers associated with ovens for the rapid heat treatment of semiconductor wafers of silicon, germanium, gallium arsenide, etc.
BACKGROUND AND OBJECTS OF THE INVENTION
It is usual, particularly in the aforesaid application, to measure the temperature prevailing inside an oven by means of an optical pyrometer. Such an instrument enables the temperature of a body (wafers to be treated) to be determined by analysing the radiation emitted by the latter without any physical contact with the body itself.
However, pyrometers are subject to loss of adjustment and/or drift particularly as a function of the number of measurements made. Up till now, in order to recalibrate such a pyrometer, a reference thermocouple was fixed to the upper face of a wafer placed in an oven and the pyrometer was recalibrated so that the readings given by the thermocouple and those given by the pyrometer coincide.
Such a calibration method has many drawbacks, the most significant of which is that it requires the installation of a thermocouple in the oven, with its electrical connections to the means for processing the signals. In the majority of applications, it is essential for the objects treated (the wafers) to be treated without any contamination and therefore without any handling. However, introducing the thermocouple into the treatment oven and passing the electrical connections through are contamination factors. Moreover, the thermocouple wires must be soldered to the wafer by means of soldering carried out with a material different from that of the wafer. Because of this, the temperature reading given by the thermocouple has an error inherent in the nature and form of the soldering. This error, which is difficult to predict, cannot be corrected in a reproducible manner.
The objective of the present invention is to mitigate all these drawbacks by providing a method and device for calibrating an optical pyrometer which do not require the introduction of any foreign bodies into the oven and allow in situ calibration of the pyrometer.
BRIEF DESCRIPTION OF THE INVENTION
To this end, the method according to the invention for calibrating an optical pyrometer consists of:
a) placing in an oven a wafer with a reference region on at least part of one of its faces, referred to as the active face, the reference region having electromagnetic wave reflection discontinuity at a known temperature,
b) transmitting an electromagnetic wave in the direction of the reference region,
c) measuring and recording the intensity of the wave reflected by the reference region,
d) measuring and recording the temperature of the reference region, by means of the optical pyrometer to be calibrated,
e) increasing the temperature of the oven,
f) determining the moment when a discontinuity in the reflection of the electromagnetic wave is observed,
g) registering the temperature value measured by the pyrometer at this moment,
h) comparing this temperature value measured with the known temperature value,
i) making the temperature value measured by the pyrometer and the known temperature value coincide.
Thus, by transmitting an electromagnetic wave, and particularly a laser wave, towards the reference region of the wafer, a radiation reflected by this reference region is created. Measuring and recording the intensity of this reflected radiation makes it possible to monitor the change in the reflection coefficient of the reference region during the period of the rise in temperature of the oven. At the same time, the pyrometer to be calibrated measures the temperature of the reference region. Determining the moment when a reflection discontinuity appears makes it possible to register the value of the temperature measured by the pyrometer at this moment. By comparing this temperature value measured and the known temperature value corresponding to the discontinuity observed, the correction to be made to the pyrometer to be calibrated is determined.
In this way a calibration is carried out, in situ, of the optical pyrometer associated with a given oven, without the introduction of any foreign body into the oven.
In a preferred method of implementing the method, a wafer is used on which the reference region consists of an active material having reflection discontinuity when it changes from the solid state to the liquid state. Preferably the known temperature is the melting point of this active material.
Preferably and in order to refine the measurement of the intensity of a reflected radiation, chromatic filtering is carried out prior to this measurement in order to eliminate therefrom any stray electromagnetic wave (originating from the heating elements in the oven, for example).
The present invention also concerns a device for calibrating an optical pyrometer associated with an oven for the purpose of giving an electrical temperature signal, characterised in that it comprises:
a wafer with a reference region having electromagnetic wave reflection discontinuity at a known temperature and suitable for being placed in the oven so that its reference region is on the axis of sight of the pyrometer to be calibrated,
an electromagnetic wave transmitter suitable for transmitting an electromagnetic wave in the direction of the reference region of the wafer,
an electromagnetic wave sensor arranged to receive the radiation reflected by the reference region and suitable for giving an electrical signal proportional to the intensity of this radiation,
signal processing means, arranged to receive the electrical signals coming from the sensor and from the pyrometer to be calibrated and suitable for detecting the moment of appearance of a discontinuity in the signal coming from the sensor and to give a signal, referred to as the calibration temperature signal, representing the temperature signal coming from the pyrometer at this moment,
means for comparing the calibration temperature signal and a reference signal representing the known temperature corresponding to the aforesaid reflection discontinuity, suitable for giving a correction signal representing the difference between these signals, and
means for correcting the pyrometer arranged to receive the correction signal and suitable for applying this signal to means for calibrating the pyrometer in order to make the calibration temperature value and known temperature value coincide.
By virtue of these arrangements, on the one hand the sensor sends an electrical signal to the signal processing means, which enables the change in the reflection coefficient of the reference region to be monitored, and on the other hand and simultaneously, the pyrometer to be calibrated makes it possible to monitor the change in the temperature of the reference region and to send, to the signal processing means, the value of the temperature which it measures. When the signal processing means detect a reflection discontinuity, the so-called calibration temperature value measured at this moment by the pyrometer is registered. The comparison means, consisting for example of electronic memories, compare the calibration temperature value with a known temperature value and then determine the correction to be made to the pyrometer in order to make these two values coincide.
Calibration of the pyrometer is thus carried out, in situ, automatically and without putting any foreign body into the oven.
According to a preferred embodiment, the known temperature value is the melting point of an active material in the reference region.
The present invention also concerns a reference wafer for calibrating an optical pyrometer, characterised in that it has an active face, an inactive face and a thickness such that the active and inactive faces are substantially isothermal, and in that it has, on at least part of its active face, a reference region having a layer of active material with a reflection discontinuity at its melting point.
By virtue of such an arrangement, when the active material in the reference region is at its melting point, a reflection discontinuity is observed. As the melting point is known very precisely, the reflection discontinuity observed makes it possible to determine accurately the moment when this known temperature is reached. It is thus possible to calibrate an optical pyrometer associated with this wafer.
In a first embodiment, the reference region covers all the active surface of the wafer.
In a second embodiment, the reference region covers only part of the active surface, the remainder of which is intended to receive a normal treatment.
Preferably the active material is a pure crystalline body and the wafer consists of a plurality of thin layers of material.
Such a method, device and reference wafer enable a temperature measuring appliance to be calibrated in situ (in an oven) without causing any foreign bodies to enter the oven.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, characteristics and advantages of the present invention will emerge from the following description, given by way of example, with reference to the accompanying drawings in which:
FIG. 1 is a diagrammatic view, partially in perspective, showing the device according to the invention,
FIG. 2 is a diagrammatic view, in section and to an expanded scale, of a wafer according to the invention and an associated pyrometer.
DESCRIPTION OF PREFERRED EMBODIMENTS
According to the embodiment described and shown in FIGS. 1 and 2, the calibration device 10 according to the invention includes an electromagnetic wave transmitter 11, a sensor 12, signal processing means 32, comparison means 31, correction means 33 and a reference wafer 18. This device makes it possible to calibrate a pyrometer 14 associated with an oven 15 containing a plurality of heating elements 16 distributed on each side of a quartz cell 17.
The oven 15 is closed off by a door (not shown) giving access to the cell 17 and making it possible to place in the latter an element to be treated 18, referred to as a wafer.
This wafer 18 rests, though its lower face, referred to as the inactive face, on supports at isolated points (not shown). Its upper face, referred to as the active face, in the example consists entirely of a reference region comprising an active material. This active material has a reflection discontinuity at its melting point. (This wafer will be described in detail below).
The electromagnetic wave transmitter 11 is generally a laser device (for example of the type sold under the name "Spectra Physics 155").
The optical sensor 12 associated with this type of transmitter is, for example, a photodiode (of the type sold under the name "OCLY 110C"). This optical sensor is fitted with a chromatic filter 19 (for example an optical filter sold under the name "ORIEL" with a 1 nm passband centred on 0.6328 μm, and a diaphragm 20). The optical sensor is connected to the signal processing means 32, to which it supplies an electrical signal proportional to the intensity of the radiation which it receives.
The pyrometer 14 is provided with a calibration unit, in this case a control potentiometer 25. Such an optical pyrometer is of the type sold under the name "IRCON" or similar. This pyrometer is located outside the oven 15 opposite an opening 26 made in this oven and is aimed at the inactive face of the wafer. The pyrometer is connected to the signal processing means 32, to which it supplies a signal proportional to the temperature of the body at which it is aimed.
Openings 27 and 28 are also made in the oven (without however impairing the effective insulation of this oven) so that an incident ray A and reflected ray R can pass.
The signal processing means 32 are connected to the sensor and pyrometer and consist of a set of electronic memories.
The comparison means 31 are connected to the signal processing means 32 and consist of a central computing unit.
Finally the correction means 33 are connected to the comparison means 31 and supply a control signal to the calibration unit 25.
The device according to the invention functions as described below.
An incident laser beam A is transmitted by the transmitter 11 in the direction of the wafer 18, and more exactly in the direction of the reference region of this wafer. The incident beam A thus passes through the opening 27 in the oven and then contacts the wafer 18 at a region I. A reflected beam R is returned and, after passing through the opening 28 in the oven, is picked up through the filter 19 by the sensor 12. This sensor supplies, to the signal processing means 32, an electrical signal proportional to the intensity of the light which it picks up. This signal is therefore a function of the reflection coefficient of the reference region.
Simultaneously the pyrometer to be calibrated 14 measures the temperature of the wafer 18 by aiming at the inactive face of the wafer 18 underneath the region I. As will be explained later, the temperatures of the wafer 18 on its active face and on its inactive face are substantially the same.
When the door to the oven 15 is reclosed, the heating elements 16 are put in operation and the temperature inside the cell increases. When the temperature in the cell is such that it causes the melting of the active layer of the wafer 18, the intensity reflected by the reference region I changes significantly and instantaneously. The signal processing means then register the temperature measured by the pyrometer, referred to as the calibration temperature, at the moment when the reflection discontinuity was observed.
The comparison means 31 compare the calibration temperature value and the reference signal representing the known temperature (t c ) corresponding to the melting point of the active material. A correction signal representing the difference between these signals results from this comparison. This correction signal is supplied to the correction means 33, which send a control signal to the calibration unit 25 of the pyrometer. Thus the calibration temperature value now corresponds to the known melting point (t c ).
The pyrometer is then correctly calibrated. It should be noted that the device described above may be provided with a transmitter, sensor, etc other than those whose commercial names are given. These names have been given only for information, for clarity of the present description.
It should be noted that the laser device used may be a continuous laser or a pulsed laser associated with synchronous detection.
When a continuous laser is used, the associated sensor 11 is provided with a diaphragm 20 for eliminating any stray electromagnetic waves.
As a variant, it is possible to replace the signal processing means 32, comparison means 31 and correction means 33 with a plotter and operator. In this case, the signal processing means consist of the plotter. This plotter prints the curves for the intensity of the reflected radiation against time and for temperature against time. The operator is substituted for the comparison means 31 and correction means 33. When the curve for the reflected radiation intensity shows an abrupt variation, the moment where this variation is observed is recorded. The operator then reads, on the measured temperature curve, the value of the calibration temperature measured at that moment. The operator compares this calibration temperature value with the known one (t c ) corresponding to the melting point of the active material in the reference region. He thus determines the difference between the calibration temperature and the known temperature. He then acts on the calibration potentiometer 25 to reduce this difference to zero.
The pyrometer is then correctly calibrated.
As stated earlier, the wafer 18 has a reference region. This wafer is preferably made up as described below. The wafer 18 is in the general shape of a disc. It is formed by a plurality of materials deposited in the form of thin layers and has an active face 29 and an inactive face 30. From the active face towards the inactive face there are respectively a protective layer 24, an active layer 21, a separation layer 22 and a support layer 23.
The protective layer 24 may optionally be omitted. The melting point of this protective layer is higher than the melting point of the active layer.
The active layer 21 consists of a pure crystalline body having a reflection discontinuity at its melting point. The separation layer is intended to prevent the active layer and support layer mixing when the active layer is melting. This separation layer has good thermal conductivity.
It is very important for the melting point of the active layer to be lower than the melting point of the layers surrounding it (that is of the separation and protective layers, and of the support layer). To achieve this, the protective layer 24 is based on silicon nitride (Si 3 N 4 ) generally deposited chemically in the vapour phase, the active layer is based on germanium (Ge), the separation layer is based on silicon dioxide (SiO 2 ) and the support layer is based on silicon (Si).
The materials mentioned above are only example embodiments. Many other materials could be used in so far as they meet the requirements laid down and set out above.
The fact that the active layer 21 consists of a pure crystalline body means that its melting point is known with very great accuracy. Because of this, the calibration of the pyrometer can be carried out with an accuracy of approximately or less than one degree. It should be noted that the protective layer 24 may be omitted. In this case, however, there is a risk that the melting active material may be deposited on the quartz cell 17 of the oven 15. For some applications it will be understood that such a deposition is not a handicap.
It should be emphasized that, because the wafer is produced in the form of thin layers of material, its thickness is minimal.
Preferably, on a very thin layer of silicon of around 250 μm, the silicon dioxide separation layer has a thickness of 5000 Å, the active layer of germanium also has a thickness of 5000 Å and the protective layer of silicon nitride is approximately 1000 Å. The total thickness of the wafer is therefore approximately 250 μm and may be less.
Given the good thermal conductivity of all the materials making up the wafer and their deposition in the form of thin layers, a wafer is obtained which is in thermal equilibrium in the vertical direction. It can thus be considered that the region where the laser beam impacts on the active face of the wafer and the region aimed at by the pyrometer situated on the inactive face underneath the laser beam impact region constitute two substantially isothermal surfaces.
Such a wafer on which the active face consists entirely of a reference region is intended to be placed regularly in the oven by means of the robot which puts the wafers in this oven, in order to calibrate the pyrometer associated with this oven. The same wafer may be reused at least ten times.
It is therefore easy to provide for an automatic calibration cycle every n wafers. As a variant, the wafer is provided, on its active face, with a reference region occupying only part of its face. In such case, the remainder of the active face is free to receive any appropriate treatment. The advantage of such a wafer is that calibration of the pyrometer may be carried out on each wafer or on some of them without having to place any special wafer in the oven. In fact, it is the conventional wafer to be treated which has a reference region on its active face but outside the treatment region.
Whatever the type of wafer used, it should be noted that no foreign body is introduced into the oven during the calibration of the pyrometer. No contamination (dust) is thus introduced. Moreover, the measurement of the reference temperature, carried out by detecting a reflection discontinuity, does not require any contact (soldering) with the wafer.
Naturally, the present invention is not limited to the different embodiments described and includes any variant within the capability of a person skilled in the art. Thus the shape and dimensions of the reference wafer may be different. The electromagnetic wave beam used may be of any kind. The active material is not necessarily germanium. Likewise, the oven associated with the pyrometer may very well not be a rapid heat treatment oven but quite simply a conventional oven. | A method of calibrating an optical pyrometer comprising placing an oven, a wafer with a reference region on at least part of one of its faces, the reference region having an electromagnetic wave reflection discontinuity at a known temperature value, transmitting an electromagnetic wave in the direction of the reference region, measuring and recording the intensity of the wave reflected by the reference region, measuring and recording the temperature of the reference region by means of the optical pyrometer to be calibrated, increasing the temperature of the oven, determining the moment when a discontinuity in the reflection of the electromagnetic wave is observed, registering the temperature value measured by the pyrometer at this moment, comparing this measured temperature value with the known temperature value, and causing the temperature value measured by the pyrometer and the known temperature value to coincide. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a process for making an oxazolidinone structures-containing prepolymeric epoxy resin mixture and to an apparatus for carrying out said process.
2. Description of Related Art
It is known from WO 90/15089 that epoxide-terminated polyoxazolidinones (in that document referred to simply as polyoxazolidones) can be prepared by reaction of a polyepoxide and a polyisocyanate at elevated temperature in the presence of a catalyst. To this end, from 5 to 30 wt % of the poly-isocyanate is added within 30 to 90 min to a mixture of 70 to 95 wt % of the polyepoxide and 0.01 to 2 wt % of the catalyst, and the resulting reaction mixture is then heated at a temperature of 110° to 200° C. for a period of 5 to 180 minutes. By regulating various process parameters, the process is carried out so that in the resulting epoxy-terminated poly-oxazolidinone, which is also referred to as isocyanate-modified epoxy resin, 50 to 100% of the original isocyanate groups are converted into oxazolidinone rings and 0 to 50% into isocyanurate rings.
In the known process, the polyepoxide is, in particular, bisphenol A or tetrabromobisphenol A, and the polyisocyanate is 4,4'-methylene-bis(phenyl isocyanate) (MDI) or an isomer thereof, polymeric MDI or toluylene diisocyanate. A suitable catalyst (for the reaction of the polyepoxide and the polyisocyanate) is, in particular, an imidazole or tetraphenylphosphonium bromide. The catalyst concentration is preferably from 0.02 to 1 wt %, particularly 0.02 to 0.1 wt %, based on the total weight of the polyepoxide and the polyisocyanate.
To prepare the polyoxazolidinones, the catalyst, optionally dissolved in a suitable solvent, is added to the polyepoxide, in general at a temperature below the reaction temperature of 110° to 200° C. The temperature is then raised to the reaction temperature and kept at this level while adding the polyisocyanate under controlled conditions, namely dropwise.
A similar process, known from EP 0 296 450 A1, is used for making oxazolidinone groups- (in that document referred to simply as oxazolidone groups) containing oligomeric polyepoxides from bisepoxides and diisocyanates. By this process, either a bisepoxy ether with OH groups corresponding to a hydroxyl number of at least 2 is made to react with an aromatic diisocyanate containing two NCO groups of different reactivity in an amount of at least 1/4 of the weight of the diisocyanate, or a bisepoxy ester with OH groups corresponding to a hydroxyl number of at least 2 is made to react with an aromatic, aliphatic or cycloaliphatic diisocyanate in a weight ratio of NCO groups to epoxide groups of 1:1.4 to 1:2.5--both reactions being carried out in the presence of a phosphonium salt as catalyst at 140° to 180° C. The catalyst is used in an amount of 0.005 to 1.0 wt %, preferably 0.01 to 0.5 wt %, based on the bisepoxide.
In this process, it is essential that the oxazolidinone epoxy resins are obtained only when OH groups-containing epoxy resins are made to react with diisocyanates containing NCO groups of different reactivity, in the presence of a phosphonium salt as catalyst at about 160° C. To prepare the polyepoxide, the bisepoxy resin and the catalyst are heated to 160° C. under nitrogen. The diisocyanate is then added dropwise to the melt at a rate such that a temperature of about 170° C. is maintained. After all the diisocyanate has been added, the mixture is allowed to agitate at 160° C. until the calculated epoxide content has been reached and reactive NCO can no longer be detected.
Both known processes have been described only for laboratory batch sizes. It is essential in this respect that the polyisocyanate be added dropwise to the catalyst-containing polyepoxide. Hence, it is hardly possible to carry out the described processes economically on an industrial scale. Moreover, by these processes only filler-free reaction resin mixtures can be used.
SUMMARY OF THE INVENTION
The object of the invention is to provide an economical process for making an oxazolidinone structures-containing prepolymeric epoxy resin mixture that is storage-stable, soluble or fusible, latently reactive and curable, which process is suitable for industrial production.
According to the invention, this objective is reached by feeding to a continuous reactor a filler-containing, heat-polymerizable reaction resin mixture of a polyepoxy resin, consisting of a mixture of di- and polyfunctional epoxy resins, and a polyisocyanate resin, with a molar ratio of epoxy groups to isocyanate groups of >1, causing the reaction resin mixture to react at a reaction temperature of up to 200° C., the reactor temperature being from 140° to 190° C., in the presence of a substituted imidazole as catalyst used in the amount of 0.5 to 2.5%, based on the polyepoxy resin, and cooling the extrudate to a temperature of <50° C. with a cooling device located at the outlet die of the reactor.
DETAILED DESCRIPTION OF THE INVENTION
By the process according to the invention, the preparation of the reaction resin mixture and the feeding thereof to the reactor can be accomplished in different ways. By a first variant, a resin component is prepared by mixing the polyepoxy resin, namely the di- and polyfunctional epoxy resins, and the polyisocyanate resin at a temperature of up to 100° C. with agitation in a thermostattable and evacuable mixing vessel equipped, for example, with a helical mixer and permitting continuous temperature measurement of the resin mixture. The filler and optionally other additives are blended into this resin mixture, said mixture then being degassed with agitation at a temperature of up to 100° C. under reduced pressure for at least 1 hour. In a second mixing vessel, a catalyst component is prepared by dissolving or dispersing the catalyst in a resin component of the formulation or in part thereof with degassing. By means of metering pumps, for example a heatable peristaltic pump or a gear pump, the two components are then introduced into a static mixing tube, and the reaction resin mixture discharged from the static mixing tube is fed to the reactor.
A twin-screw extruder is particularly well suited for reaction extrusion of the resin mixture fed via the static mixing tube in the described manner. It is advantageous that the ratio of screw length to outside screw diameter of the extruder be from 20 to 50 and particularly from 25 to 40. Moreover, the extruder is preferably designed so that for a screw speed of >10 rpm the residence time of the material is less than 5 min and preferably less than 3 min and that axial backflow is minimized.
The extruder which is continuously fed with amounts of resin from 20 to 200 g/min contains conveying screw elements (screw diameter, for example, 31.8 mm, screw length:880 mm) and is equipped with five thermostattable barrel zones which are heated, for example, to 160°-180 ° C. Thus, the residence time available for the conversion of the reaction resin mixture into the prepolymeric epoxy resin mixture in the reactor is less than 3 minutes. The extrudate discharged through a slot die is rapidly cooled to a temperature below 50° C. on a cooled slide-off ramp, the epoxy resin mixture thus solidifying to ribbon-like continuous strips. On a take-off belt, said strips are pulled under a counter-roll and coarsely comminuted. The pre-comminuted product is ground to the desired particle size in an impact mill. The free-flowing, storage-stable, soluble or fusible, latently reactive oxazolidinone structures-containing prepolymeric epoxy resin mixture thus obtained is stored with exclusion of moisture.
By a second variant, the resin component is prepared as in the first case. The catalyst component is prepared by vigorously mixing the catalyst with part of the filler of the formulation and optionally with additives. The two components are then fed to a twin-screw extruder by means of a peristaltic pump or a twin-screw powder-metering device. The difference between this variant and the first one is that the screws in the mixing zone of the extruder which is adjacent to the feeding zone are provided with conveying kneading elements. The temperature in the mixing zone is up to 100° C. The other features of the extruder and the processing conditions are substantially the same as for variant 1.
By a third variant, a resin component is prepared by separately feeding a polyepoxy resin and a polyisocyanate resin, which are liquid and possibly highly viscous, from heatable storage containers by means of piston, membrane or gear pumps at continuous flow rates to a twin-screw mixing extruder or to a twin-screw extruder extended by adding a premixing section. At a different downstream location, a free-flowing premix of catalyst, filler and optionally additives is fed by means of a twin-screw metering device. Downstream of an appropriate partial mixing section, a vacuum system is provided for degassing the material to remove volatile components. The temperatures in the entire mixing section are up to 100° C. The screws of the mixing extruder or the premixing zone of the reaction extruder contain mostly mixing elements. When a separate mixing extruder is used, the resin component is fed with the mixing extruder and the catalyst component is fed to the reaction extruder with a twin-screw metering device, as in the second case. When an extended extruder is used, the catalyst component is fed at the end of the mixing section by means of a twin-screw metering device. From this point on, the conditions are comparable to those prevailing downstream of the feeding zone in the second variant.
The process according to the invention involves the use of a reaction resin mixture of polyepoxy resin and polyisocyanate resin, the polyepoxy resin being a mixture of di- and polyfunctional epoxy resins. The molar ratio of polyfunctional to difunctional epoxy resin is from 0.1 to 1.7, preferably 0.2 to 0.75, based on the epoxy groups. The molar ratio of epoxy groups to isocyanate groups (in the reaction resin mixture) is >1 and preferably 1.5 to 4.0.
According to the process of the invention, suitable epoxy resins used as components of the polyepoxy resin mixture are in particular bisphenol A and bisphenol F epoxy resins, phenol novolak and cresol novolak epoxy resins or silicone epoxy resins, triglycidylisocyanurate,tetraglycidyldiamino-diphenylmethane and polyglycidylphosphorus resins. Particularly suitable silicone epoxy resins are those having the following structure: ##STR1## wherein n is an integer from 0 to 25,
x is an integer from 0 to 3,
R=alkyl or aryl,
Q=--(CH 2 ) 3 SiR 2 O(SiR 2 O) n SiR 2 R 1 ,
n and R having the afore-indicated meaning and R 1 denoting a group bearing epoxy functionality and having 6 carbon atoms.
The silicone epoxy resin is used in an amount of up to 20%, preferably 1 to 7%, based on the filler-free reaction resin mixture of polyepoxy resin and polyisocyanate resin.
Preferred polyisocyanate resins are isomer mixtures of diphenylmethane diisocyanate. Also suitable are, for example, toluylene diisocyanate isomer mixtures and prepolymers of diphenylmethane diisocyanate isomer mixtures. Mixtures of said polyisocyanate resins can also be used.
Substituted imidazoles are used as catalysts (i.e. reaction accelerators) for the process of the invention. Preferred are 2-ethyl-4-methylimidazole, 2-phenylimidazole and 1-cyanoethyl-2-phenylimidazole. Other suitable catalysts are, for example, 1,2-dimethylimidazole, 1-cyanoethyl-2-methylimidazole, 2-isopropylimidazole and 1-benzyl-2-phenylimidazole. The catalyst is used in an amount of 0.5 to 2.5%, preferably 1.0 to 1.8%, based on the polyepoxy resin, namely the mixture of the di- and polyfunctional epoxy resins.
Suitable fillers are, in particular, mineral fillers, such as fused quartz with angular (i.e. splintery) and/or spherical particles (of varying particle size distribution). Moreover, ceramic fillers such as aluminum oxide and mixtures of ceramic and mineral fillers can be used. Fibrous fillers, such as short glass fibers, are also suitable.
Whereas according to the prior art, as indicated in particular by the practical examples of said prior art, low catalyst concentrations are used, namely from 0.01 to 0.35% (WO 90/15089) or 0.1% (EP 0 296 450 A1), in both cases based on the polyepoxide, substantially higher amounts of catalyst are needed to prepare reactive, curable prepolymeric epoxy resin mixtures. Hence, in the process according to the invention, the catalyst concentration is from 0.5 to 2.5%, preferably from 1.0 to 1.8%, based on the mixture of di- and polyfunctional epoxy resins. Such high catalyst concentrations are required to ensure the curing of the latently reactive prepolymeric epoxy resin mixture within an industrially relevant time without post-catalysis, which for filler-containing systems would be expensive.
A process for economical conversion of a reaction mixture of polyepoxy and polyisocyanate resins to an oxazolidinone structures-containing, storage-stable, soluble or fusible, latently reactive, curable, prepolymeric epoxy resin mixture in the presence of such high catalyst concentrations on an industrial scale was not known to date. This is due to the necessity to control large amounts of heat generated by the reactions taking place and the phase transitions from the viscous to the solid state and from the solid state back to the viscous state. We have now found that both the large amounts of heat and the phase transitions are controllable if--according to the process of the invention--the preparation of the prepolymeric epoxy resin mixture is carried out with the aid of a continuously operating reactor.
The preparation of epoxy resin materials from epoxy resins and phenols by reaction extrusion is known from EP 0 193 809 A2. The resulting reaction products are chain-extended epoxy resins or resins with phenolic end groups, depending on the molar ratio of epoxy groups to phenolic hydroxyl groups used. The preparation of resin materials by extrusion of epoxy resins and compounds containing thiol, carboxyl, isocyanate, thioisocyanate or secondary amino groups has also been reported, but detailed information about such preparations illustrated by examples is not available. Moreover, the reported experimental conditions are not applicable to epoxide/isocyanate systems.
It is particularly important for the preparation of the epoxy resin mixture according to the invention that the screws of the reaction extruder in the extruder sections that do not serve to mix the components (but serve for carrying out the reaction) are provided exclusively with conveying elements. On the one hand, this ensures that the torque stress of the extruder is minimized and that the shearing and perpendicular forces of the rotating screws will prevent the formation of a region of compact solid material. On the other hand, as a result of a narrow residence time distribution of the extrudate, it ensures exact and uniform temperature control with a uniform temperature profile for the entire extrudate. Moreover, it is essential that the dissipation energy owing to the mechanical action of the screws on the reaction resin mixture be minimized by the exclusive use of conveying elements and that the high reaction enthalpy generated during the melting of the prepolymeric epoxy resin mixture be removed by intensive cooling of the extrudate after it has emerged from the die of the extruder. To this end, the extruder die is designed to produce an extrudate with a maximum surface area--relative to the extrusion volume--and to allow immediate cooling by means of the cooling device located at the extruder die.
Those skilled in the art could not have predicted the possibility that, in the preparation of the prepolymeric epoxy resin mixture according to the invention, the use of a polyfunctional epoxy resin such as tetraglycidyldiamino-diphenylmethane and the said silicone epoxy resins and the use of a high catalyst concentration would not, even at a reaction temperature of up to 200° C., bring about curing, namely chemical crosslinking, with formation of an insoluble, no longer fusible reaction product. Surprisingly, an oxazolidinone structures-containing, storage-stable, soluble or fusible, latently reactive, curable, prepolymeric epoxy resin mixture which is readily curable without post-catalysis, is obtained.
The composition of the reaction resin mixture of polyepoxy resin and polyisocyanate resin used in the process according to the invention differs markedly from that of the reaction mixtures used according to the prior art. In fact, on the one hand, the reaction resin mixtures according to the invention are highly filled (filler content up to 80% and higher) and--because of their high viscosity--require different preparation and handling conditions than do unfilled, low-viscosity reaction resin mixtures. On the other hand, the highly filled reaction resin mixtures are prepared from mixtures of epoxy resins of different chemical structure and different functionality. Such mixtures are not known from the prior art not does the prior art mention the particularly well suited catalyst 1-cyanoethyl-2-phenylimidazole or the silicone epoxy resins of said type, which are important for processing properties, or the tetraglycidyldiaminodiphenylmethane which is especially useful for raising the glass transition temperature.
The process of the invention is well suited for the industrial production of storage-stable, latently reactive, curable oxazolidinone structures--containing prepolymeric epoxy resin mixtures. The reported conditions will enable those skilled in the art to carry out the process on any required industrial scale.
The following examples illustrate the invention in greater detail.
EXAMPLE 1
A resin component was prepared by blending 2.52 kg of bisphenol A epoxy resin (epoxide content:5.78 mol/kg), 0.155 kg of a silicone epoxide (epoxide content:1.9 mol/kg) prepared as described in Example 9 of EP-OS [OS=unexamined patent application] 0 399 199, and 0.885 kg of a diphenylmethane diisocyanate isomer mixture (isocyanate content:7.9 mol/kg) in a thermostattable, evacuable mixing vessel (effective capacity:20 L) at a temperature of up to 90° C. with mixing. To this mixture were added in portions and with mixing 7.245 kg of spherical fused quartz, 3.105 kg of angular fused quartz and 0.15 kg of carbon black, and the mixture was degassed 1 hr at 90° C. with mixing. A catalyst component was prepared by mixing and then degassing 1.62 kg of tetraglycidyldiamino-diphenylmethane (epoxide content:8.2 mol/kg) and 81.2 g of 2-phenylimidazole at 60° C. in a thermostattable, evacuable mixing vessel (effective capacity:2 L). By means of a peristaltic pump, the resin component was fed to a static mixing tube at a constant rate of 0.1 kg/min. At the same time, the catalyst component was metered into the static mixing tube by means of a gear pump (rate:6.5 g/min). From the static mixing tube, the material was fed to a twin-screw extruder the screws of which were provided with conveying elements. The screw length was 880 mm and the outside screw diameter was 31.8 mm. The five barrel zones of the extruder were heated at 160° C. The screw speed was 20 rpm and the residence time of the material in the twin-screw extruder was 2.5 minutes.
The extrudate emerging from a double slot die (cross-section 1.5 mm×20 mm each) passed over a cooled slide-off ramp and was thereby cooled to 45° C. It was then comminuted by a counter-roll on an attached elastic haul-off belt, and the pre-comminuted extrudate was ground to the desired particle size in an impact mill. The resulting free-flowing, latently reactive, curable oxazolidinone structures-containing prepolymeric epoxy resin mixture (epoxide content:0.89 mol/kg; melting range:75°-95° C.) was stored at room temperature with exclusion of moisture.
EXAMPLE 2
A resin component was prepared by charging to a thermostattable, evacuable mixing vessel (effective capacity:20 L) 2.55 kg of bisphenol A epoxy resin (epoxide content:5.78 mol/kg), 0.155 kg of a silicone epoxide (epoxide content:1.9 mol/kg) prepared as described in Example 9 of EP-OS 0 399 199, 0.81 kg of tetraglycidyldiaminodiphenylmethane (epoxide content:8.2 mol/kg) and 0.885 kg of a diphenylmethane diisocyanate isomer mixture (isocyanate content:7.9 mol/kg) and heating the mixture to 60° C. with mixing. To this mixture were then added in portions and with mixing 6.195 kg of spherical fused quartz, 2.655 kg of angular fused quartz and 0.135 kg of carbon black. The mixture was then degassed 1 hr at 60° C. under reduced pressure (<1 mbar). A catalyst component was prepared by uniformly mixing 1.05 kg of spherical fused quartz, 0.45 kg of angular fused quartz, 0.015 kg of carbon black and 55.5 g of 1-cyanoethyl-2-phenylimidazole. The resin component and the catalyst component were metered simultaneously into a twin-screw extruder, the resin component by means of a peristaltic pump at a rate of 0.042 kg/min and the catalyst component by means of a twin-screw metering device (rate:5 g/min). The screws of the extruder were fitted with conveying elements, and three 28 mm long conveying kneading blocks were provided immediately downstream of the feeding zone for uniform mixing of the resin component with the catalyst component. The screw length was 880 mm and the outside screw diameter was 31.8 mm. The five barrel zones of the extruder were set at the following temperatures:zone 1 (mixing zone):81° C., zone 2: 130° C., zone 3: 177° C., zone 4: 178° C., zone 5: 180° C. The screw speed was 20 rpm and the residence time of the material in the twin-screw extruder was 2.5 minutes.
The extrudate emerging from a double slot die (cross-section 2 mm×20 mm each) passed over a cooled slide-off ramp and was thereby cooled to 43° C. It was then comminuted by a counter-roll on an attached elastic haul-off belt, and the pre-comminuted extrudate was ground to the desired particle size in an impact mill. The resulting free-flowing, latently reactive, curable oxazolidinone structures-containing prepolymeric epoxy resin mixture (epoxide content:0.84 mol/kg; melting range:75°-95° C.) was stored at room temperature with exclusion of moisture.
EXAMPLE 3
A resin component was prepared by charging to a thermostattable, evacuable mixing vessel (effective capacity:50 L) 10.08 kg of bisphenol A epoxy resin (epoxide content:5.78 mol/kg), 0.62 kg of a silicone epoxide (epoxide content:1.9 mol/kg) prepared as described in Example 9 of EP-OS 0 399 199, 3.24 kg of tetraglycidyldiaminodiphenylmethane (epoxide content:8.2 mol/kg) and 3.42 kg of a diphenylmethane diisocyanate isomer mixture (isocyanate content:7.9 mol/kg) and heating the mixture to 80° C. with mixing. To this mixture were then added in portions and with mixing 26.084 kg of spherical fused quartz, 11.18 kg of angular fused quartz, 0.3 kg of polyethylene wax and 0.54 kg of carbon black. The mixture was then degassed 1 hr at 60° C. under reduced pressure (<1 mbar). A catalyst component was prepared by uniformly mixing 2.9 kg of spherical fused quartz, 1.244 kg of angular fused quartz, 0.06 kg of carbon black and 222 g of 1-cyanoethyl-2-phenylimidazole. The resin component and the catalyst component were metered simultaneously into a twin-screw extruder, the resin component by means of a membrane metering pump at a constant rate of 0.25 kg/min and the catalyst component by means of a twin-screw metering device at a constant rate of 21 g/min. The screws of the extruder were fitted with conveying elements, and three 40 mm long conveying kneading blocks were provided immediately downstream of the feeding zone for uniform mixing of the resin component with the catalyst component. The screw length was 1485 mm and the outside screw diameter was 42 mm. The six barrel zones of the extruder were set at the following temperatures:zone 1 (mixing zone):75° C., zone 2: 120° C., zone 3: 170° C., zone 4: 175° C., zone 5: 175° C., zone 6: 170° C. The screw speed was 25 rpm and the residence time of the material in the twin-screw extruder was 2.4 minutes.
The extrudate emerging from a double slot die (cross-section 3 mm×25 mm each) passed over a cooled slide-off ramp and was thereby cooled to 45° C. It was then comminuted by a counter-roll on an attached elastic haul-off belt, and the pre-comminuted extrudate was ground to the desired particle size in an impact mill. The resulting free-flowing, latently reactive, curable oxazolidinone structures-containing prepolymeric epoxy resin mixture (epoxide content:0.87 mol/kg; melting range:75°-95° C.) was stored at room temperature with exclusion of moisture.
EXAMPLE 4
A resin component was prepared by charging to a thermostattable, evacuable mixing vessel (effective capacity:100 L) 25.2 kg of bisphenol A epoxy resin (epoxide content:5.78 mol/kg), 1.55 kg of a silicone epoxide (epoxide content:1.9 mol/kg) prepared as described in Example 9 of EP-OS 0 399 199, 8.1 kg of tetraglycidyldiaminodiphenylmethane (epoxide content: 8.2 mol/kg) and 8.85 kg of a diphenylmethane diisocyanate isomer mixture (isocyanate content:7.9 mol/kg) and heating the mixture to 80° C. with mixing. To this mixture were then added in portions and with mixing 61.95 kg of spherical fused quartz, 26.55 kg of angular fused quartz and 1.35 kg of carbon black. The mixture was then degassed 1 hr at 80° C. under reduced pressure (<1 mbar). A catalyst component was prepared by uniformly mixing 10.5 kg of spherical fused quartz, 4.0 kg of angular fused quartz, 0.15 kg of carbon black and 417 g of 2-phenylimidazole. The resin component and the catalyst component were metered simultaneously at constant rates into a twin-screw extruder, the resin component by means of a membrane metering pump (rate:2 kg/min) and the catalyst component by means of a twin-screw metering device (rate:238 g/min). The screws of the extruder were fitted with conveying elements, and nine 80 mm long conveying kneading blocks were provided immediately downstream of the feeding zone for uniform mixing of the resin component with the catalyst component. The screw length was 3480 mm and the outside screw diameter was 91.8 mm. The ten barrel zones of the extruder were set at the following temperatures: zones 1 and 2 (mixing zones): 81° C., zone 3: 130° C., zones 4 to 8: 175° C., zone 9: 173° C., zone 10: 170° C. The screw speed was 20 rpm and the residence time of the material in the twin-screw extruder was 2.8 minutes.
Further processing was as described in Example 3. The resulting free-flowing, latently reactive, curable oxazolidinone structures-containing prepolymeric epoxy resin mixture (epoxide content:0.85 mol/kg; melting range: 75°-95° C.) was stored at room temperature with exclusion of moisture. | In a process for producing a prepolymer epoxy resin mixture with oxazolidinone structures, a filler-containing thermally polymerizable reaction resin mixture of polyepoxy resin, consisting of a mixture of di- and multifunctional epoxy resins, and polyisocyanate resin, with a molar ratio of the epoxy groups to the isocyanate groups of >1, is fed to a continuously working reactor. With substituted imidazole as reaction accelerator, amounting to 0.5-2.5% of the polyepoxy resin, the reaction resin mixture is then reacted at temperatures up to 200° C., with reactor temperature at 140°-190° C., and following that the extruded material is cooled down to a temperature of <50° C. with the aid of a cooling device mounted at the outlet die of the reactor. | 1 |
BACKGROUND OF THE INVENTION
The present invention is directed to a method for offering a phantom target for protection of land, air or water craft or the like against missiles having a target searching head that operates in the infrared (IR) or radar (RF) range or in both wavelength ranges simultaneously or serially. Information regarding modern, autonomously operating missiles will clearly increase since missiles even with the most modern target searching systems are becoming wide-spread due to the collapse of the former superpower of the Soviet Union as well as due to liberal export regulation, particularly of Asiatic countries. The target seeking systems of such missiles work mainly in the radar range (RF) and in the infrared range (IR). Both the radar back-scatter behavior as well as the emission of specific infrared radiation from targets such as, for example, ships, aircraft, tanks, etc., are thereby used for target finding and target tracking. Developments in modern missiles are clearly proceeding in the direction of multi-spectral target seeking systems that work simultaneously or serially in the radar and infrared range in order to be able to implement an improved spurious target discrimination. Multi-spectral IR target seeking heads work with two detectors that are sensitive in the short-wave and long-wave infrared range for spurious target discrimination. What are referred to as dual mode target seeking heads operate in the radar and in the infrared range. Missiles with such target seeking heads are radar-controlled in the approach and seek phase and switch to an infrared seek head in the tracking phase. One target criterion of dual mode target seeking heads is the co-location of the radar range back-scatter and of the infrared center of radiation. Spurious targets (for example clutter such as older types of phantom bodies) can be better separated on the basis of the possible comparison of target coordinates. The co-location of radar range and infrared effectiveness is consequently a compulsory pre-requisite for a dual mode phantom member in order to effectively fool modern dual mode target seeking heads, that is in order to steer them from an object to be protected onto a phantom target. Only the smallest possible resolution cell of the target seeking head (RF and IR) is thereby relevant for the co-location.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method for offering a phantom target available with which both IR-guided and RF-guided as well as dual-mode-guided missiles can be diverted from the actual target, that is from the object to be protected, and steered onto a phantom target.
This object is inventively achieved in that a mass that emits radiation in the IR range (IR active mask) and a mass back-scattering RF radiation (RF active mass) are simultaneously brought into effect in the correct position as phantom target.
It can thereby be provided that the active masses are positioned by a projectile placed in rotation without a shell casing surrounding the active masses.
Advantageously, the active masses are activated and distributed with an activation and distribution means. In particular, it can thereby be provided that an ignition and blow-out unit centrally arranged in the projectile is employed as activation and distribution means.
A pyrotechnic charge can also be employed for ignition and blow-out, this being triggered by an ignition delay means that is fired by the burn-out of a propulsion charge for the projectile.
Beneficially, the pyrotechnic charge for the ignition and blow-out unit is burned off within a tube that is arranged centrally in the projectile and is provided with defined blow-out openings.
Active masses can also be employed that are arranged in the projectile in longitudinal direction thereof.
The RF active mass is thereby beneficially employed that has its generated surface surrounded by a paper, cardboard or plastic foil envelope.
It can also be alternatively provided that the active masses are positioned by a projectile placed in rotation and having a shell casing surrounding the active masses.
It can thereby be provided that the active masses, including an activation and distribution means, are ejected from the shell casing in common during the flight phase of the projectile with an ejection part and are subsequently activated and distributed. What is thereby achieved given a projectile with a shell casing surrounding the active masses is that the active masses are distributed without being blocked up and, thus, an excess pressure does not influence the active masses in the distribution of the active masses. Accordingly, the distribution of the IR active mass and, in particular, the distribution of the RF active mass can be improved in a long-lasting way. Moreover, the activation of the IR active mass is clearly improved, as a result whereof the effectiveness of the IR active mass with respect to the radiation intensity per volume unit as well as with respect to the emitting area increases compared to methods without ejection of the active masses.
It can thereby be provided that a propulsion charge is employed for the ejection of the ejection part, this propulsion charge being fired by a detonation delay means that is ignited by the burn-off of an ejection propulsion charge for the projectile.
The ejection propulsion charge for the ejection part is preferably ignited with a pyrotechnic detonation delay means.
Beneficially, a detonation blow-out unit centrally arranged in the ejection part is employed as activation and distribution means for the activation and distribution of the IR active mass as well as for the distribution of the RF active mass.
It can thereby be provided that a pyrotechnic charge is employed for detonation and blow-out, this pyrotechnic charge being ignited by a detonation delay means that is ignited by the burn-out of the ejection propulsion charge for the ejection part.
It can also be provided that the detonation delay means is ignited when the effective masses are ejected from a casing.
Beneficially, the pyrotechnic charge of the ignition and blow-out unit is burned off within a pipe centrally arranged in the ejection part and provided with defined blow-out openings.
It can also be provided that active masses are employed that are successively arranged in the ejection part in longitudinal direction of the ejection part.
It can also be provided that a RF active mass is employed that has its generated surface surrounded by an aluminum, paper, cardboard or plastic foil envelope.
Aluminum potassium per chlorate or magnesium barium nitrate is preferably employed as pyrotechnic charge.
Active masses are preferably employed that are annularly arranged around the ignition and blow-out unit.
Advantageously, the ignition and blow-out charge is employed in an amount matched such to the plurality and to the cross-section of the blow-out openings employed that greater accelerating forces do not act on the active masses. The quantity of ignition and blow-out charge in relationship to the plurality and the cross-section of the blow-out openings, namely, defines the speed with which the ignition and blow-off charge is burned off. Given the same charge amount, the burn-off speed increases with the decrease of the overall cross-section of the blow-out openings. The inventive quantity selection for the ignition and blow-off charge assures that no abrupt pulse corresponding to an explosion is exerted on the active masses instead of a uniform thrust. An improved firing and distribution of the RF active masses as well as an improved distribution of the RF active mass compared to traditional explosion principles is thus assured. The improved firing and distribution of the active masses in turn leads to an improved performance yield of the active masses employed.
According to a specific embodiment of the invention, it can be provided that the projectile is placed into rotation by a rotation motor. In particular, it can thereby be provided that the projectile is placed in rotation by a pyrotechnic rotation motor.
On the other hand, it can also be provided that the projectile is placed into rotation on the basis of appropriately fashioned flues in the shell cup. It can also be provided that the projectile is placed into rotation by appropriately fashioned air baffle surfaces of the projectile.
It can also be provided that a projectile having a caliber in the range from about 10-155 mm is employed.
In another, specific embodiment of the invention, rolled-up radar dipoles of aluminum-coated or silver-coated fiberglass threads having a thickness in the range from about 10-100 μm are employed as RF active mass. Such dipoles have a high scattering capability in the radar wave range according to antenna laws as well as the Mie law. Over and above this, they distribute excellently in air and also exhibit good quotation capability.
Beneficially, dipoles having a dipole length that corresponds to half the anticipated radar wavelength λ multiplied by the refractive index n of the air are employed, that is the dipole length is matched, among other things, to the radar wavelength λ of the anticipated target-seeking head.
Beneficially, the dipoles are employed in a plurality of more than one million per kilogram.
Advantageously, dipole packets are employed that are arranged such they open immediately when blown out.
According to another, especially advantageous embodiment, dipole packets are employed that are protected against the blow-out heat by at least one heat shield.
In particular, it can be provided that at least one foil that extends through the entire RF active mass is respectively employed as heat shield or shields.
It can also be provided that a heat-resistant, elastic foil is respectively employed as heat shield or shields.
According to another particular embodiment of the invention, dipole packets are employed at, for protecting them from sliding into one another, are respectively separated from one another by at least one heat-resistant foil.
It can also be provided that an IR active mass with flares having center-wave radiation part (MWIR flares) is employed.
It can particularly be provided that MWIR flares according to German Letters Patent 43 27 976 are employed.
Finally, it can be provided that an RF active mass is employed whose share in the overall active mass amounts to more than 50%. This has proven especially advantageous on the basis of trials.
The invention is based on the surprising perception that an effective phantom target that not only steers dual mode target-seeking heads but also target-seeking heads that were at only one wavelength range (IR or, respectively, RF range) from an object to be protected is offered by a simultaneous employment of an RI and a RF active mass that are activated simultaneously and at the same location (co-location). A phantom member that works according to the inventive method thus enables the simultaneous diversion with mixed attacks of IR-guided and RF-guided missiles and of dual-mode-guided missiles. When, according to a particular embodiment of the invention, the projectile is placed into rotation, this leads, first, thereto that the projectile is stabilized on its flight path and, second, also leads thereto that an effective turbulence and laying of the active masses is guaranteed by the centrifugal force when the target location is reached. This is directly possible insofar as the active masses are fired without a shell casing surrounding them. Insofar as, however, the active masses are fired with a shell casing surrounding them, a similarly good three-dimensional distribution in the air is achieved by the particular embodiment of the method wherein the active masses are ejected from the shell casing together with the activation and distribution means and are only subsequently activated and distributed.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention which are believed to be novel ,are set forth with particularity in the appended claims. The invention, together with further objects and advantages, may best be understood by reference to the following description taken in conjunction with the accompanying drawing, in which:
FIG. 1 is a schematic diagram of an embodiment of the inventive method;
FIG. 2 is a sectional view of an embodiment of a phantom member working according to the inventive method;
FIG. 3 is a schematic view of a RF active mass of the phantom member according to FIG. 2; and
FIG. 4 is a sectional view of another embodiment of a phantom member working according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates the fundamental method execution according to a specific embodiment of the present invention. The inventive method can be presented best in terms of the time sequence from the firing of a phantom member working according to the inventive method up to the distribution of the active masses. The time sequence can be roughly divided into four phases:
Phase I--Firing a phantom member
Phase II--Twist-stabilized flight phase of the phantom member.
Phase III--Ejection of the RR and RF active mass; and
Phase IV--Activation and distribution of the active masses.
FIG. 1 schematically shows Phases II-IV. The detonation and the firing according to Phase I proceeds according to the prior art. In Phase II, the phantom member comprises a twist-stabilized flight phase in order to make sure that the RF and IR active masses are flooded in a defined way. The rotational pulse is largely preserved until the active masses are distributed and is transmitted onto the active masses, this in turn resulting in an improved distribution of the active masses. In Phase III, the active masses including an activation and distribution mechanism are ejected from the shell casing of the disguised member during flight in order to achieve a subsequent distribution of the active masses without blocking, this providing the advantage that an excess pressure does not act on the active masses during the distribution of the active masses. This leads to the fact that the distribution of the IR active mass but, in particular, the distribution of the RF active mass is improved in a long-lasting way. In Phase IV, an effective distribution of the active masses is achieved by rotation and air flow as well as by a central blow-out.
FIG. 2 shows a longitudinal section through a phantom member that works according to the specific embodiment of the inventive method outlined in FIG. 1. A complete secondary part for inductive absorption of detonation energy from a primary part is referenced 1. The secondary part 1 is composed of magnetic material, preferably iron. The ignition energy is induced in a secondary coil 2. The windings of the secondary coil are composed of copper wire treated with insulating lacquer. The plurality of turns preferably corresponds to that of a primary coil, whereby, however, a transformation is fundamentally possible. A preferably beaded floor cover 3 serves as lower securing termination of the phantom member. The floor cover 3 is preferably composed of metal. Execution with glass-reinforced or carbon fiber-reinforced plastic, however, is also possible. The outer firing member is formed by a housing casing 4 that is preferably composed of pure aluminum with an aluminum part of more than 99%. The housing casing 4 remains in the magazine. A floor ring 5 creates a distance from a pressure chamber 6. The pressure chamber 6 accepts the propulsion gas that arises when a propulsion charge 8 is burned for ejecting the phantom member shell. Over and above this, the pressure chamber 6 is necessary in order to form a closed pressure space for igniting a rotation motor. The propulsion charge 8 is ignited with a firing charge 7 that is preferably composed of a powder drive unit, preferably black powder or drive units similar to black powder such as nitrocellulose powder.
Rotation charges 9 are preferably composed of compressed powder propellent with additional binder for mechanical stabilization such as, for example, black powder with plastic binder, or are composed of a commercially obtainable solid-state rocket fuel unit. Density, shape, surface and depth of the rotation charges 9 define the burning parameters such as burning duration and pulse/time unit. The specific pulse is determined by the selection of the drive unit. The rotation charges 9 are preferably fashioned fuel-like and are preferably pressed into combustion chambers (see reference numeral 10). This pressing-in of the rotation charges 9 mainly serves the purpose of stabilizing the burning behavior since the surfaces of the rotation charges 9 facing the metal and not the combustion chamber do not burn. There is also the possibility of controlling the burning behavior by a passivation of the surfaces. Another possibility for controlling the burning behavior is comprised of the known method of shaping such as, for example, star burner. The quantity of rotation charge 9 is dependent on the burning behavior and on the desired pulse/time behavior. A burning time of approximately 1.5 seconds was realized for this exemplary embodiment.
The reference numeral 10 identifies rotation jets including the aforementioned combustion chamber. The rotation jets are composed of a jet net and of a jet cone that are both preferably mulled or, respectively, drilled from a solid cast aluminum part. The jet cone preferably comprises a slope of approximately 10° through 20° from the jack axis. The length of the jet neck is preferably less than the length of the jet cone. The combustion chamber is preferably cylindrically fashioned. The combustion chambers are connected by an annular channel in order to achieve a pressure compensation that effects a uniform burning. The jet axis is slanted radially relative to the projectile. The jet axis should preferably slant by more than 30° relative to the radius of the projectile since the pulse would otherwise contribute only little to generating the rotation. Angles greater than 80° relative to the radius cause excessive turbulence at the transition from the combustion chamber to the jet neck and thus effect a deterioration of the thrust. A detonation delay means 11 serves the purpose of defining the flight distance up to the ejection of an IR active mass 19 and of a RF active mass 21. The detonation delay means 11 is pyrotechnically implemented and has a burning time of two seconds. Such detonation delay means are commercially obtainable. However, the employment of a freely programmable, electronic detonation delay means is also conceivable for variable definition of the flight time.
A connecting part 12 connects the rotation motor to an ejection part 14 for the active masses 19 and 21. The connecting part 12 contains the detonation delay means 11 and an ejection propulsion charge 13 for the ejection of the ejection part 14. The connecting part 12 is preferably fabricated of metal. The ejection propulsion charge 13 comprises a powder drive unit, preferably black powder or drive units similar to black powder such as nitrocellulose. The ejection part 14 serves as drive mirror for the ejection propulsion charge 13 and is executed such that it serves as holder for the detonation delay means 15 and for a blow-out pipe 16. The blow-out part 14 is preferably fabricated of a cast or milled aluminum part. The detonation delay means 15 comprises a pyrotechnic delay piece that ignites a detonation/resolver unit 18 when the ejection part 14 has left the shell casing. The detonation delay means 15 has a burning time of approximately 0.1 seconds. The blow-out pipe 16 serves as receptacle for the detonation/resolver unit 18 and for controlling the blow-out speed. The blow-out speed is dependent on the length of the blow-out pipe 16 and of the ratio of the overall cross-section of blow-out openings 17 to the quantity of detonation/resolver unit 18. It can be generally stated that the blow-out speed is all the higher the higher the quantity of detonation/resolver unit 18 and the smaller the overall cross-section of the blow-out openings 17. The relationship is preferably selected such in the exemplary embodiment that a blow-out time of 0.1 seconds is achieved. The blow-out pipe 16 must be fabricated such that no plastic deformation occurs insofar as possible during the blow-out event. In the exemplary embodiment, the blow-out pipe 16 was manufactured of steel. The blow-out openings 17 must be attached such that a uniform distribution of the RF and IR active masses 19 and 21 is achieved. This is preferably achieved such that respectively one blow-out opening 17 needs one layer of the RF active mass 21.
The detonation/resolver unit 18 comprises a pyrotechnic unit that delivers a comparatively great quantity of gas as combustion product. Magnesium barium nitrate or aluminum perchlorite of per chlorate are preferably employed for this purpose. The quantity of detonation/resolver unit 18 is dependent on the blow-out pipe 16. The IR active mass 19 contains the cap IR active mass with MWIR flares disclosed by German Patent 43 27 976. Fundamentally, however, all IR active masses can be employed that an be activated by a detonation charge. In the exemplary embodiment, disk-shaped MWIR flares with a 1/3 division are employed. A parting disc 20 protects the RF active mass 21 from the burning MWIR flares of the IR active mass 19. The parting disc 20 can be fabricated of metal or, preferably, of fire-resistant foil. The embodiment of the RF active mass 21 is shown in greater detail in FIG. 3. For reasons of heat protection, rolled-up radar dipoles with dipoles of aluminum-coated or silver-coated fiber glass threads having a thickness in the range from about 10-100 μm are employed as RF active mass 21. The dipole length amount to 17.9 mm. However, dipole lengths from about 1 mm to about 25 mm are also possible and provided. The plurality of wrappings of the individual dipole packets (chaff packets) is variable from one on up. 1.5 wrappings are preferably employed for the packets. The ejection of the active masses before the activation and distribution as well as the suitable "packaging" of the dipoles serves the purpose of avoiding a clumping and fusing and that of producing a spacing from dipole to dipole of about 7-10 λ and, thus, a high radar back-scattered cross-section. The packaging must basically be flexible enough to automatically release the dipoles without external influence and in order to protect them against the influence of heat due to the detonation and blow-out charge. Moreover, the packaging of the dipoles is adapted to the distribution principle, i.e. the package dipoles are arranged such that they open immediately when blown out. Capton® or Milinex® are preferably employed as material for the wrappings and for the protective foils 31 and protective foils 32 going through entirely through the RF active mass to prevent dipoles from sliding into one another. Aluminum foils of various thicknesses can also be employed as intermediate foils 32. A thin aluminum envelope 33 that, however, can also be a paper or cardboard sheath, insures that the RF active mass 21 does not divide immediately after being ejected from the projectile shell but remains together until the detonation/resolver charge 18 has burned. It is thus assured that the overall energy of the charge can act on the RF active mass 21. A cover 23 serves the purpose of terminating a projectile casing 22 and fixes the blow-out pipe 16 from above. The cover 23 can be fabricated of heavy metals such as, for example, cast iron or brass in order to shift the center of gravity of the phantom member as far toward the front as possible. A stabilization of the flight can thereby be achieved envision to the rotation. The cover 23 is sealed from the projectile casing 22--which is preferably drawn from aluminum having a purity degree of more than 99%--by a seal ring 24. 25 represents a closure piece of the blow-out pipe 16 and assures that the relative dangerous resolver charge is introduced into the phantom member as last work step.
FIG. 4 shows another embodiment of a phantom member that functions according to a specific embodiment of the method. The same reference characters as in FIG. 2 are used in FIG. 4. Only the differences compared to the phantom member of FIG. 2 shall be discussed below. One critical difference is comprised therein that the projectile comprises no shell casing (identified with reference number 22 in FIG. 2). The IR active mass 19 and RF active mass 21 thus need not be ejected from the projectile casing before their activation and distribution and, thus, the ejection propulsion charge (identified with reference numeral 13 in FIG. 2) for the ejection part 14 as well as the detonation delay mean (identified with reference numeral 15 in FIG. 2) are no longer necessary and are therefore no longer present. The ejection part 14 also no longer serves the purpose of ejecting the active masses 19, 21 from the shell casing. The RF active mass 21 is surrounded by a paper or, respectively, cardboard sheath 33a instead of being surrounded by an aluminum sheath (reference number 33 in FIG. 3). This paper, or, respectively, cardboard envelope 33a, together with the central blow-out pipe 16, suffices to keep the RF active mass 21 together before the actual activation and distribution despite the air flow in the flight phase. A safety element 15 as disclosed, for example, by German Reference DE 19651974.8 sees to the pre-pipe safety. Further, the rotation charge (reference numeral 9 in FIG. 2) and rotation jet (reference numeral 10 in FIG. 2) are replaced by a rotation motor 9a. As a result of the lacking shell casing, the phantom member shown in FIG. 4 exhibits the advantage that it is simpler to manufacture and significantly less expensive compared to a phantom member having shell casing.
Both individually as well as an arbitrary combination, the features of the present invention disclosed in the above description, in the drawings as well as in the claims are important for realizing the various embodiments of the invention.
The invention is not limited to the particular details of the method depicted and other modifications and applications are contemplated. Certain other changes may be made in the above described apparatus without departing from the true spirit and scope of the invention herein involved. It is intended, therefore, that the subject matter in the above depiction shall be interpreted as illustrative and not in a limiting sense. | The method offers a phantom target for protecting land, air or water craft or the like against missiles that have a target seeking head operating in the infrared (IR) or radar (RF) range or simultaneously or serially in both wavelength ranges. A mass emitting radiation in the IR range (IR active mass) and a mass back-scattering RF radiation (RF active mass) are simultaneously brought into action in the correct position as phantom target. | 5 |
This is a division of application Ser. No. 08/667,639 filed Jun. 21, 1996, now U.S. Pat. No 5,905,919.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an automatic focusing device, for use in a picture pickup device such as a camera, which detects the focus state of the objective lens by receiving light reflected back from a subject through the lens and keeps the lens in focus.
2. Description of the Related Art
Conventionally, a focus detecting technique has been developed which forms two images by reimaging beams of light reflected back from a subject that pass through first and second areas, respectively, of the objective lens which are symmetrical in position with respect to the optical axis and seeks the positional relation between the two images, thereby obtaining a displacement of a position in which the two images are formed by the objective lens from the predetermined position of its focus and the direction of the displacement, i.e., information as to whether the imaging position of the objective lens is in front of or at the rear of the predetermined focus position.
FIG. 16 shows an arrangement of the optical system in a focus detecting device based on such a conventional technique. The optical system includes a predetermined focal plane (position) 111 at the rear of an objective lens 38, a condenser lens 36 behind the plane 115, and reimaging lenses 35L and 35R behind that condenser lens. Image sensors 34L and 34R are placed on the image formation planes of the respective reimaging lenses 35L and 35R.
As indicated at 116L and 116L in FIG. 17, the images of a subject on the respective image sensors 34L and 34R draw to the optical axis 100 in the case of the so-called front focus condition in which a subject to be brought into focus is imaged in front of the predetermined focal plane 115. In the so-called rear focus condition, on the other hand, they are away from the optical axis 100. When the subject is brought into focus, the spacing between two corresponding points each of which is on a respective one of the images formed on the sensors 34L and 34R reaches a specific distance which is uniquely defined by the arrangement of the optical system in the focus detecting device, i.e., the in-focus time spacing.
In principle, therefore, the state of focus will be known by detecting the spacing between two corresponding points on the two images. The spacing between the two corresponding points can be detected by seeking correlation between two light intensity distributions on element areas of the image sensors 34L and 34R, shifting the position of the element area of one of the images sensors 34L and 34R with respect to the other, and seeking the spacing between the element areas of the image sensors for the best correlation is obtained.
With an automatic focus adjusting device having such a focus detecting optical system built in, the seeking of the shifted position for the best correlation, calculation of the spacing between the two images, calculation of the amount of defocus indicating the state of focus, calculation of the amount by which the lens is to be driven, and driving of the lens are performed under program control of microcomputer-based control means.
In addition, a focus detection related technique is disclosed in Japanese Unexamined Patent Publication No. 1-187521 which detects the state of focus of the objective lens by receiving light reflected back from a subject through the objective lens. In this technique, when the focus detection is impossible, a low contrast scan operation is performed to search for the lens location that enables the focus detection while the lens is driven. That is, according to this technique, when it is decided that the focus detection is impossible, the range over which the focus detecting operation is performed with the lens driven is limited to a narrow one, thereby reducing the time it takes to make a decision that the focus detection is impossible.
Moreover, in Japanese Unexamined Patent Publication No. 62-187829 is disclosed an automatic focus detecting technique for use in a camera in which a plurality of focus detecting areas of different sizes are set up so as to make a subject easy to pick up and the focus detecting areas are switched by a photographer on his judgment of the condition of the subject. That is, when an object is present in a scene to be shot that obstructs the focus detecting operation, a focus detecting area in the shape of a small spot is selected, while, when it is desired to shoot a moving subject, a large focus detecting area is selected, thereby improving the accuracy of focus detection.
Furthermore, a focus detecting technique is disclosed in Japanese Unexamined Patent Publication No. 63-17418, which, at first, detects focus using a small focus detecting area and, when a focus undetectable state is detected, uses a larger focus detecting area. This technique improves the accuracy of the focus detection as in shooting a moving subject by making the focus detecting area variable.
However, the conventional focus detecting techniques described above each have a range of defocus amount over which the focus is detectable which depends on the arrangement of their optical system.
The focus detectable defocus range varies according to the size of a focus detecting area on focus detecting photosensitive elements even with the same optical system used.
This will be described below.
FIG. 18 shows an example of setting up focus detecting areas on the image sensors 34L and 34R and seeking the relative position of those areas in which the best correlation between light intensity distributions on the sensors is obtained.
In the upper half of FIG. 18, a focus detecting area a1 is fixed on the image sensor 34L and a focus detecting area a2 is shifted on the image sensor 34R and correlation between light intensity distributions on the focus detecting areas a1 and a2 is taken for each shifted position. In this case, the spacing between the focus detecting areas a1 and a2 when the area a2 is shifted to the position in which the best correlation is obtained is sought. The magnitude and sign of the difference between that spacing and the in-focus time spacing indicate the amount and direction of focus displacement, respectively.
The lower half of FIG. 18 shows the case where focus detecting areas b1 and b2 which are respectively larger than the focus detecting areas a1 and a2 are set up.
In the case of the focus detecting areas a1 and a2, the focus-detectable range of defocus amount is 12a-11a. In the case of the focus detecting areas b1 and b2, the corresponding range is 12b-11b. Both the ranges are related such that (12b-11b)<(12a-11a) It can therefore be said that the focus-detectable range of defocus amount for the focus detecting area b is smaller than that for the area a.
On the other hand, the amount of defocus of an objective (photo-taking) lens varies according to the distance between a subject and the lens over the range from the closest focusing distance to infinity. In general, the longer the focal length of an objective lens, the larger its maximum range of defocus becomes. If the defocus amount of an objective lens is larger than the focus detectable defocus range at the time of shooting, the focus detection will become impossible.
In the above-described technique disclosed in Japanese Unexamined Patent Publication No. 63-17418, at first the focus detection is performed through a small focus detecting area and, when the focus detection is impossible, a larger focus detecting area is used. As described above, when a large focus detecting area is used, the focus detectable defocus range decreases. Thus, when the defocus range of an objective lens is so large as to exceed the focus detectable defocus range for a small focus detecting area, the focus detection becomes impossible. Further, even if a large focus detecting area is used, the focus cannot be detected. A time delay involved in displaying on the viewfinder or the like that the focus detection is impossible further increases, thus making photographers feel strange. In addition, the low contrast scan operation performed when the focus detection is impossible would further increase the time delay.
Further, when a subject is in low light, a problem arises even if the low-contrast operation is performed in that the focus detection is substantially impossible because the integration time required for the amount of charge stored in the image sensor to reach a level suitable for focus detection increases. When a subject is in lower light and the use of assist light is required for focus detection, the focus detection is impossible if the amount of defocus of an objective lens exceeds the focus-detectable amount of defocus with the first focus detecting areas. In this case, even if the second focus detecting areas larger than the first ones is used for focus detection, the focus detection is still impossible because the focus-detectable amount of defocus is exceeded, resulting in a useless operation and a time lag.
SUMMARY OF THE INVENTION
The object of the invention is to provide an automatic focus adjusting device which permits the time required to detect the focus to be reduced without using a low contrast scan too much even when the focus detection is impossible, permits the focus to be detected in a short time without using the low contrast scan even when a subject is in low luminance and for which the amount of defocus is large, and permits the focus to be detected even with a subject for which the amount of defocus is large when it is in low luminance and hence requires the use of assist light for focus detection.
According to an aspect of the invention there is provided an automatic focus adjusting device which detects focus information of an objective lens on the basis of two images of a subject, comprising: photosensor means having a number of pixels on which said two images are formed; focus detecting area setup means for selectively setting up either of first and second focus detecting areas on said photosensor means, said first focus detecting areas being initially set up and said second focus detecting areas being less in the number of pixels than said first focus detecting areas; operations means for performing predetermined operations on outputs of said first focus detecting areas set up on said photosensor means to provide focus information of said objective lens; evaluation means for evaluating whether the results of operations by said operations means are proper or not; and control means responsive to said evaluation means for, when the results of operations are improper, causing said focus detecting area setup means to set up said second focus detecting areas on said photosensor means and then causing said operations means to perform said operations on outputs of said second focus detecting areas.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate a presently preferred embodiment of the invention and, together with the general description given above and the detailed description of the preferred embodiment given below, serve to explain the principles of the invention.
FIG. 1 is a conceptual diagram of an automatic focus adjusting device of the invention;
FIG. 2 is a conceptual diagram of an automatic focus adjusting device of the invention;
FIG. 3 is a conceptual diagram of an automatic focus adjusting device of the invention;
FIG. 4 is a conceptual diagram of an automatic focus adjusting device of the invention;
FIG. 5 shows an arrangement of a control system of a camera using an automatic focus adjusting device according to an embodiment of the invention;
FIG. 6 is a block diagram of the AFIC in FIG. 5;
FIG. 7 shows signals at the terminals of the AFIC shown in FIG. 6;
FIG. 8 shows an arrangement of the flash shown in FIG. 5;
FIG. 9 is a flowchart for a subroutine "fast release" carried out by the camera shown in FIG. 5;
FIG. 10 is a flowchart for the subroutine "focus detection" shown in FIG. 9;
FIG. 11 is a flowchart for the subroutine "autofocus assist light decision" shown in FIG. 9;
FIG. 12 is a flowchart for the subroutine "correlation operation b" shown in FIG. 9;
FIG. 13 is a flowchart for the subroutine "correlation operation a" shown in FIG. 9;
FIGS. 14(a) and 14(b) schematically show changes in position of blocks (area) of image sensors on which correlation between subject images L(i) and R(i) is taken in the procedure of FIG. 12;
FIG. 15 is a graph illustrating a relation of FM, Fmin and FP;
FIG. 16 shows an arrangement of the optical system of a conventional automatic focus adjusting device;
FIG. 17 shows an arrangement of the optical system of a conventional automatic focus adjusting device; and
FIG. 18 is a diagram illustrating an operation of setting up focus detecting areas on the image sensors of FIGS. 16 and 17 and detecting the relative position of the detecting areas for the best correlation between light intensity distributions on the detecting areas.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIGS. 1 to 4 there are illustrated conceptual diagrams of an automatic focus adjusting device of the invention.
The automatic focus adjusting device shown in FIG. 1 is constructed from a focus detecting photosensor unit 1, a focus detecting area switching unit 2 for switching between first focus detecting areas 3 and second focus detecting areas 4 smaller than the first areas which are set up on the photosensor unit 1, and a focus detection execution unit 5 for performing focus detection on the basis of the first or second focus detecting areas selected by the switching unit 2.
In such an arrangement, first, the focus detecting area switching unit 2 sets up the first focus detecting areas 3 on the focus detecting photosensor unit 1 and the focus detection execution unit 5 performs the focus detection on the basis of the first focus detecting areas 3. If the focus detection with the first focus detecting areas 3 is impossible, then the switching unit 2 switches from the first focus detecting areas 3 to the second focus detecting areas 4 smaller than the first ones and the focus detection execution unit 5 performs the focus detection on the basis of the second focus detecting areas. The focus detection based on the second focus detecting areas 4 is larger in the detectable range of defocus than the focus detection based on the first focus detecting areas. With the second detecting areas, therefore, the focus detection becomes possible even for an objective lens for which the focus detection is impossible with the first focus detecting areas 3.
The automatic focus adjusting device shown in FIG. 2 is arranged such that an assist light source 6 is added to the arrangement of FIG. 1. When it is required to direct assist light from the light source 6 onto a subject for focus detection, the focus detecting area switching unit 2 selects the second focus detecting areas 4 larger in the detectable range of defocus than the first areas 3.
The automatic focus adjusting device shown in FIG. 3 is constructed from a focus detecting photo-sensor unit 1, a first focus detector 8, a second focus detector 9 which is larger than the first detector in the detectable range of defocus, a selector 7 for selecting between the first and second focus detectors 8 and 9, and an assist light source 6 for directing assist light onto a subject.
If, in such an arrangement of FIG. 3, it is required to direct assist light from the light source onto a subject for focus detection, then the selector 7 selects the second focus detector 9 having a larger detectable range of amount of defocus. The second focus detector performs focus detection on the basis of the output of the focus detecting photosensor unit 1. Thus, by using assist light, the focus detection is made possible with a subject for which the amount of defocus is large.
The automatic focus adjusting device shown in FIG. 4 is constructed from a focus detecting photosensor unit 1, a low luminance decision unit 7 for making a decision as to whether a subject is in low luminance or not, a focus detecting area switching unit 2 for switching between first and second focus detecting areas 3 and 4 which are equivalently set up on the photosensor unit 1, the second area being smaller than the first area, and a focus detection execution unit 5 for performing focus detection on the basis of the first or second focus detecting area.
If, in such an arrangement of FIG. 4, a decision by the decision unit 7 is that the subject is in low luminance, then the focus detecting area switching unit 2 selects the second area 4 and the focus detection execution unit 5 performs the focus detection on the basis of the second area.
Next, the control system of a camera using an automatic focus detecting device according to an embodiment of the invention will be described with reference to FIG. 5.
In the automatic focus adjusting device, light reflected back from a subject passes through an objective lens 38 and is then directed onto photosensor arrays 34L and 34R, i.e., image sensors, disposed on the top of an AFIC 112 through a focus detecting optical system 37 composed of a condenser lens 36 and reimaging lenses 35L and 35R.
The AFIC 112 performs a charge storage operation to be described later and sends light intensity distribution information to a CPU 111.
The CPU 111 sequentially carries out programs stored in its internal ROM and controls peripheral circuit blocks. The CPU 111 has an A/D converter built in. The CPU performs calculations for focus detection on the basis of the light intensity distribution information from the AFIC 112 and drives a focusing lens in the object lens 38 accordingly, thereby adjusting the focus.
An E 2 PROM 113 is a nonvolatile memory which stores correction values and adjust values for correcting mechanical variations in the camera body and variations in electrical characteristics of various elements. The CPU reads out such correction values from the ROM 113 as required and performs correction calculations to make various corrections.
A databack 15, connected to the CPU 111, imprints date on film in responsive to control signals from the CPU. Note that the amount of light from an imprinting lamp in the databack 15 is changed in steps according to film speed (ISO). An interface (IFIC) 17 makes parallel communication of 4-bit data with the CPU 111 for measurement of the luminance of a subject, measurement of the temperature inside the camera, waveshaping of output signals of a photointerrupter and the like, control of constant-voltage drive of motors, temperature stability, production of various constant voltages such as a voltage proportional to temperature, etc., battery check, reception of signals for infrared remote control, control of motor drivers 18 and 19, control of LEDs, supply voltage check, control of a booster, etc.
A silicon photodiode (SPD) 33 measures the luminance of a subject and has its light receiving surface segmented into two: center and periphery. Thus, two types of metering are provided: centerweighted spotmetering based on only the center of the SPD, and average metering using the entire surface of the SPD. The SPD 33 provides a current corresponding to the luminance of the subject to the IFIC 17, which, in turn, converts it into a voltage for transmission to the CPU 111. Upon receipt of the voltage, the CPU performs calculations for exposure and makes a backlight/nonbacklight decision.
When a voltage signal that is made to correspond to absolute temperature is output from a built-in circuit of the IFIC 17, it is converted by the A/D converter into a digital signal indicating the measured value of the temperature inside the camera. This digital signal is used as the criterion for corrections of mechanical members and electric signals which are subject to change according to temperature.
The waveshaping of the photointerrupter output signals is performed such that photocurrents output from the photointerrupter or photoreflector are compared with a reference current, then output from the IFIC 17 as rectangular currents. At this point, noise reduction is achieved by imparting a hysteresis characteristic to the reference current. It is also possible to change the reference current and the hysteresis characteristic by communication with the CPU 111.
The battery check is made on the basis of a digital value obtained by connecting a resistor of low resistance across a battery not shown, dividing a voltage across the resistor within the IFIC 17, and subjecting the resulting voltage to A/D conversion within the CPU 111. The reception of infrared remote control signals is performed by receiving an infrared light emitted modulated by an LED (light emitting diode) 31 of a remote control transmitter 30 by means of a silicon photodiode 32. The output signal of the photodiode 32 is subjected to waveshaping within the IFIC 16, then output to the CPU 111.
The supply voltage is checked such that the IFIC 17 is provided with terminals which are dedicated to the check of the supply voltage and, when the supply voltage applied to the dedicated terminals of the IFIC 17 goes lower than a specific value, a reset signal is output from the IFIC to the CPU to thereby avoid the occurrence of errors in the CPU in advance. When the supply voltage goes lower than the specific value, it is boosted by the booster.
To the IFIC 17 are connected LEDs 29 for viewfinder display for focus confirmation, flash ready, etc., and an LED used in the photointerrupter. The control of on/off of and the amount of light emitted by these LEDs is directly performed by the IFIC 17 which makes communications with the CPU 111 and the EEROM 113. The IFIC performs constant-voltage control of the motors as well.
The motor drive IC 18 drives a shutter-charge (SC) motor 22 for film advance and shutter charge, a lens driving (LD) motor 23 for focus adjustment, a zooming (ZM) motor 24, the booster circuit, and an LED for self-timer indication. The control of operations, for example, "which device is to be driven", "whether the motor is to be driven in the forward direct ion or the reverse direction", and "whether the brake is to be applied", is performed by the IFIC 17 controlling the motor driver IC 18 in response to the reception of signals from the CPU 111.
An SCPI 25 detects which of the shutter charging, film advancing and film rewinding states the SC motor 22 is placed in by using the photointerrupter and a clutch lever. The resulting information is sent to the CPU 111. The amount of outward movement of the lens is detected by an LDPI 26 mounted on the LD motor 23. The output of the LDPI is shaped by the IFIC 17, then sent to the CPU 111.
Further, the amount of outward movement of the lens barrel in zooming is detected by a ZMPI 28 and a ZMPR 27. When the lens barrel stays between TELE and WIDE settings, reflections from a silver seal attached to the barrel is picked up by the ZMPR 27. The output of the ZMPR is input to the CPU 111 to detect the TELE or WIDE setting position.
The ZMPI 28 is mounted on the ZM motor 24 and has its output waveshaped by the IFIC 17 and then entered into the CPU 111, thereby detecting the amount of zooming from the TELE or WIDE setting position. The motor driver IC 19 drives an AV motor (stepping motor) 20, for driving a member for adjusting the aperture in response to a control signal from the CPU 111. An AVPI 21 has its output waveshaped by the IFIC and entered into the CPU to detect the open position of the aperture.
A liquid crystal (LC) display panel 114 is responsive to signals from the CPU to display film frame counter, exposure modes, flash modes, aperture, battery condition, etc. Controlled by the IFIC 17 responsive to a control signal from the CPU 111, a flash unit 16 activates a flash tube to emit light when the luminance of the subject is insufficient at the time of shooting or autofocusing.
A fast release switch RLSW is turned on when the shutter release button is half depressed, whereby an autofocusing operation is performed. A second release switch R2SW is turned on when the release button is fully depressed, whereby a shooting operation based on various measured values is performed. A zoom-up switch ZUSW and a zoom-down switch ZDSW are switches adapted to move the lens barrel. When the switch ZUSW is turned on, the lens barrel is moved in the direction of long focal lengths, while, when the switch ZDSW is turned on, the lens barrel is moved in the direction of wide-angle focal lengths. When a self-timer switch SELFSW is turned on, the camera is placed in the self-timer shooting mode or the wait state for remote control operation. When, in this state, the switch R2SW is turned on, the self-timer-based shooting is performed. On the other hand, when a shooting operation is performed on the remote control transmitter 30, the remote-control-based shooting is performed.
When a spot switch SPOTSW is turned on, the spotmetering mode is set in which metering is performed using only a portion of the center of the shooting frame. This is metering by an AF sensor to be described later. The normal metering with the SP0TSW turned off is evaluative metering by the metering SPD 33. Switches PCT1SW to PCT4S and a program switch PSW are changeover switches for program modes and are selected by a photographer to suit shooting conditions. When the PCT1SW is turned on, a portrait mode is set in which the aperture and shutter speed are determined within a proper exposure range so that limited depth of field will be provided.
When the switch PCT2SW is turned on, a night scene mode is set in which exposures are set one stop under proper exposures in normal shooting situations. When the switch PCT3SW is turned on, a scenic mode is set in which the aperture and shutter speed are determined within a proper exposure range so that as great a depth of field as possible will be provided. Further, when the switch PCT4SW is turned on, a macro mode is set for close-distance shooting. The switches PCT1SW to PCT4SW can be selected two or more at a time.
The switch PSW is a program mode changeover switch which, when pressed, resets the switches PCT1SW to PCT4SW and an AV (Aperture Value)-priority program mode to be described later. When an AV-priority switch AVSW is turned on, the shooting mode is switched to the AV-priority program mode. In this mode, a photographer sets an AV value and the camera sets the proper-exposure, program-selected shutter speed. The switches PCT2SW and PCT4SW loses their functions described above and serve as AV-value setting switches. More specifically, the switch PCT2SW is adapted to make the AV large, while PCT4SW is adapted to make the AV small.
A flash switch STSW swichtes flash modes including an autoflash mode (AUTO), a red-eye reduction autoflash mode (AUTO-S), a forced flash mode (FILL-IN), and a flash-off mode (OFF). A panorama switch PANSW is adapted to detect whether the shooting mode is the panorama mode or the normal mode and is turned on in the panorama mode. In the panorama mode, calculations are performed for exposure compensation. This is because, in the panorama mode, the top and bottom of film frames are masked and a portion of the light sensor is masked accordingly, failing to achieve accurate metering.
A back-cover switch BKSW detects the state of the back cover of the camera and is in the off position when the back cover is closed. When the switch BKSW makes a transition from on to off state, the film loading is started. A shutter charge switch SCSW detects the shutter being charged. A mirror-up switch MUSW is adapted to detect the mirror-up state and turned on when the mirror is raised. A DX switch DXSW, which, though not shown, is actually composed of five switches, is adapted to read the film-speed indicating DX code printed on the film cartridge and detect whether film is loaded or not.
The flash unit 16 charges the built-in capacitor in response to a signal from the CPU 111. The CPU detects the voltage across the capacitor through its divided output and stops the charging of the capacitor when its voltage reaches a predetermined level. Upon receipt of a flash signal from the CPU through the IFIC, the flash unit is fired to emit a burst of light. In the present embodiment, the flash unit 16 is used as a source of autofocus assist light.
Next, an arrangement of the IFIC 12 will be described with reference to FIG. 6.
Charges produced by light incident on arrays 34L and 34R of photosensors are stored on capacitors inside an amplifier AP and amplified, the capacitors having a one-to-one correspondence with the photosensors. Each pixel signal amplified in the amplifier AP is converted by a monitor output circuit MO to a signal corresponding to the peak value (maximum value) of all pixels and then output to the A/D converter in the CPU 111 via a terminal MDA.
On the other hand, each pixel signal from the amplifier AP is output in sequence by a shift register SR from a terminal SDATA in synchronism with a clock signal output from the CPU to a terminal CLK. The signal is applied to the AD converter in the CPU. A control circuit CNT controls the operation of each circuit block in the AFIC 112 in response to control signals RESET, END and CLK from the CPU 111. The amplifier AP is supplied with a reference voltage VREF from the IFIC 17.
At this point, signals at the terminals of the IFIC shown in FIG. 6 will be described with reference to FIG. 7.
When a RESET signal at a low level is output from the CPU 111, each circuit block in the IFIC 112 is initialized. When the RESET signal goes high, the storage operation is started. As described above, the pixel output corresponding to the peak level of each pixel is output at the terminal MDATA.
In FIG. 7, a and b each indicate the amount of incident light and a is larger than b. After the start of storage operation, the CPU 111 converts the MDATA signal into digital form to monitor the storage level. At the time the proper storage level is reached, the CPU 111 causes the END signal to go from the high level to the low level, thereby stopping the storage operation. An amount of time during which the charge storage is performed, i.e., the interval between the time at which the RESET signal goes from the low level to the high level and the time at which the END signal goes from the high level to the low level is counted by an internal counter and then stored as an integration time.
As shown at MDATA in FIG. 7, the integration time varies with the amount of incident light. On the basis of the integration time, the CPU 111 determines the luminance of a subject. Next, the CPU provides to the terminal CLK a clock signal for reading the pixel signals. The pixel signals are output in sequence to the terminal SDATA in synchronism with the clock signal. In the CPU, the pixel signals are converted into digital form and stored in its internal RAM as pixel data.
Next, an arrangement of the flash unit 16 will be described with reference to FIG. 8.
In parallel with a power supply E is connected a DC/DC converter 52 which converts the supply voltage to a voltage that allows the flash unit to emit light. To the output of the DC/DC converter is connected a main capacitor voltage measuring circuit 53 which measures the voltage across the main capacitor MC. To the output of the converter are also connected a trigger circuit 54 which triggers an Xe (xenon) tube 57 to emit light. Further, the main capacitor MC which stores light emitting energy is also connected to the converter output through a diode D1. To the cathode of the diode are connected in series the Xe tube 57 which dissipates the energy in the main capacitor MC to emit light and a control circuit 55 which controls the amount of light emitted by the Xe tube. A power supply control circuit 56 supplies the boosted voltage to the light emission control circuit 55. The control of the DC/DC converter 52, the main capacitor voltage measuring circuit 53, the trigger circuit 54, the light emission control circuit 55 and the power supply control circuit 56 is performed by the CPU 111 with the IFIC 17 used as interface.
Next, reference will be made to a flowchart illustrated in FIG. 9 to describe the fast release procedure carried out by the camera of the invention.
First, the CPU 111 carries out the subroutine "focus detection" to be described later (step S1) and makes a decision of whether the result of focus detection indicates undetectability by making reference to a flag indicating whether the focus is detectable or not (step S2). When the decision is that the focus is detectable, reference is made to an in-focus flag to make an in-focus/out-of-focus decision (step S3). When the decision is in-focus, the CPU 111 provides in-focus indication with an LED within the viewfinder or with a beep (step S6) and then returns to a general photographing sequence.
If, on the other hand, the decision in step S3 is out-of-focus, then the CPU carries out the subroutine "lens drive" to move the focusing lens on the basis of the result of focus detection (step S4). In the subroutine "lens driver", when the amount of lens drive is smaller than a predetermined value, a subject is considered to be in focus and the in-focus flag is set without confirmation of whether the subject has been brought into focus by detecting the focus again. Next, the CPU 111 makes a decision of whether the subject is in focus or not by making reference to the in-focus flag (step S5). If the decision is in-focus, the in-focus indication is provided as described previously (step S6); otherwise, the procedure returns to step S1 to perform the subroutine "focus detection" again.
If, in step S2, the focus is undetectable, then the CPU 111 makes a lens scan to search for the lens location where the focus is detectable (step S7). If the lens location where the focus is detectable is not found as a result of the lens scan, then the CPU 111 provides out-of-focus indication with the LED within the viewfinder (step S9) and then returns to the general photographing sequence.
If, on the other hand, the lens location where the focus is detectable is detected in step S8, then the procedure returns to step S1, so that the CPU detects the focus again at that lens location.
The subroutine "focus detection" in step S1 in the flowchart of FIG.9 is carried out in accordance with the procedure shown in FIG. 10.
First, reference is made to an assist-light request flag that is set in the subroutine "assist light decision" (step S14) to make a decision of whether a subject is in such a luminance as requires assist light (step S11). If that flag has been set, then the CPU 111 sets an assist-light-on flag (step S25) and then performs integration while irradiating the subject with the assist light (step S26), performs data readout (step S13), and performs the subroutine "assist light decision" (step S14).
On the other hand, when a request for assist light is not made in step Sll, the CPU 111 causes the AFIC 112 to perform normal integration (step S12). At this point, the CPU counts the integration time in the AFIC by using its internal counter. Next, the CPU provides clock pulses to the AFIC 112 to read pixel data representing light intensity distribution and converts the pixel data read in sequence from the AFIC into digital form by the A/D converter and then stores it into its internal RAM (step S13).
Next, the subroutine "assist light decision" is carried out (step S14), whereby a decision is made as to whether the subject is in such a luminance as requires assist light and the assist-light-request flag is set if necessary.
That is, as shown in FIG. 11, in the subroutine "assist light decision", the CPU 111 clears the assist-light-request flag (step S30), make reference to the assist-light-on flag set in step S24 in FIG. 10 to make a decision of whether this integration has been performed under the condition that the assist light is on (step S31), sets the assist-light-request flag when the assist light is on (step S34), and returns the procedure to step S15.
On the other hand, if the decision in step S31 is that the assist light is off, then the CPU 111 makes a comparison between the integration time in the AFIC and a first predetermined time in order to make a decision of whether the subject is at a low light level at which the effect of the lens scan is small or at such a lower luminance as requires assist light.
When the integration time is shorter than the first predetermined time, the decision is that the subject is not at a low luminance. In such a case, the CPU returns the procedure to step S15. If the integration time is longer than or equal to the first predetermined time, then the integration time is compared with a second predetermined time longer than the first time (S33). If the integration time is shorter than the second time, then the assist light is unnecessary. In this case, a low-luminance flag is set in step S35 and the procedure returns to step S15 of FIG. 10.
If, on the other hand, the integration time is not shorter than the second time, the assist-light-request flag is set and the procedure returns to step S15.
In step S15 of FIG. 10, reference is made to the assist-light-on flag to select between the focus detecting areas. If the assist light is off, then a subroutine "correlation operations b" to be described later is carried out, whereby the correlation based on the larger focus detecting area b is sought (step sl6). If the focus is detectable, the procedure goes to step S20.
On the other hand, if the decision in step S15 is that the assist light is off and if the decision in step S17 is that the focus is undetectable, then the CPU 111 carries out a subroutine "correlation operations a", whereby correlation based on the smaller focus detecting area a is sought (step S18). Subsequent to the subroutine "correlation operations a", a decision is made as to whether the focus is detectable or not (step S19). If the focus is detectable, then the amount of defocus of the lens is calculated on the basis of the result of the focus detection (step S20).
If, on the other hand, the decision in step S19 is that the focus is undetectable, then the CPU sets the undetectability flag (step S23) and returns the procedure to step S2 in FIG. 9. The amount of defocus of the lens calculated in step S20 is compared with an in-focus threshold to decide if the subject is in focus or not (step S21). If the subject is in focus, then the in-focus flag is set (step S24); otherwise, the amount of drive of the lens is calculated on the basis of the amount of defocus of the lens (step S22). The procedure then returns to step S2 in FIG. 9.
Next, reference is made to FIG. 12 to describe the operation of the subroutine "correlation operations b" in step S16 of FIG. 10.
In this subroutine, correlation operations are performed on two images of a subject to detect the spacing therebetween. Let the subject images on the photodiode arrays 34L and 34R be represented by L and R images, respectively, and pixel signals indicating light intensity distributions on the L and R images on the photodiode arrays 34L and 34R be represented by L(i) and R(i), respectively. Here, i represents the pixel number and takes 0, 1, 2, . . . , 99 in the order of arrangement in this embodiment. That is, the photodiode arrays 34L and 34R each have 100 pixels.
First, variables SL, SR and J are set to 0, 60, and 7, respectively (steps S40, S41). The SL is a variable to store the number of the first pixel of a pixel array (block) which is used for correlation operations in the subject image signal L(i). The SR is a variable to store the number of the first pixel of a block pixel string on which correlation operations are to be performed in the subject image signal R(i). The variable J is one to count the number of times the block is shifted in the subject image signal R(i).
The correlation F(S) between the block pixel strings is calculated in step S42 by ##EQU1## In this case, the number of pixels in each block is 40.
Subsequently, a comparison is made between F(S) and Fmin to detect the minimum value of the correlation F(S). If F(S)<Fmin, then F(S) is substituted for Fmin and SL and SR are stored as SLM and SRM, respectively (steps S43 and S44). Further, SR and J are each decremented by one (step S45).
If J is not 0 in step S46, the procedure returns to step S42 to repeat the correlation operations. That is, in this example, the correlation is taken while the block location in the subject image R(i) is shifted pixel by pixel with the block location in the subject image L(i) fixed (steps S42 to S45).
When J reaches 0 in step S46, 4 is added to SL and 3 is added to SR (step S47). Until SL reaches 56, the correlation operations are repeated (step S48). That is, the block location in the subject image L(i) is set shifted by four pixels. And when SL reaches 56 in step S48, the shifting of the block location for the correlation detection is terminated.
By the above operations, the correlation can be detected in an efficient manner to obtain the minimum value of the correlation. The block locations SLM and SRM at which the correlation output indicates the minimum value indicate the locations of the subject images that are most highly correlated. In FIGS. 14a) and 14(b) there is schematically shown changes in the locations of the subject image blocks L(i) and R(i) adapted for correlation detection. However, the block locations in FIGS. 14(a) and 14(b) do not coincide exactly with those described in connection with the flowchart of FIG. 12 for the convenience of illustration.
In order to determine the reliability of block image signals thus calculated to be most highly correlated, FM and FP are calculated in step S49 by ##EQU2##
That is, the correlation between that block of the subject image R(i) which is shifted by ±1 pixel with respect to its most highly correlated block and the most highly correlated block of the subject image L(i) is calculated. In this case, FM, Fmin and FP are related as shown in FIG. 15. In FIG. 15, the ordinate represents the correlation output and the abscissa represents the difference in location between subject image blocks L(i) and R(i) for which correlation is taken.
Subsequently, in order to determine the reliability of the correlation, the reliability index SK is calculated in step S50 as follows:
when FM≧FP, ##EQU3## or, when FM<FP, ##EQU4## When the reliability is high, SK=1; otherwise, SK>1. Using the reliability index SK, a decision is made as to whether the calculated correlation is reliable, i.e., whether the focus is detectable or not.
Next, reference will be made to FIG. 13 to describe the subroutine "correlation operations a". Here, only steps that are distinct from the steps in FIG. 12 will be described. First, the variables SL, SR and J are set to 0, 80, and 7, respectively (steps S51 and S52). The correlation output F(S) is calculated in step S53 by ##EQU5##
In this case, the number of pixels in a block is set to 20.
The subsequent steps from step S54 to step S58 are exactly identical to the corresponding steps in the subroutine "correlation operations a" in FIG. 12. The correlation operations are repeated until SL becomes equal to 76 in step S59. In the lower portion of FIG. 14, there is schematically illustrated changes in the location of blocks for the correlation operations a. In this figure, the range of image displacement corresponding to the detectable range of defocus is (Zb2-Zb1) for the correlation operations b and (Za2-Za1) for the correlation operations a. The detectable range of defocus in the correlation operations a is larger than in the correlation operations b.
As with the correlation operations b, FM, FP and SK are calculated in steps S60 and S61 and the procedure returns to step S19 in FIG. 10.
The detectable range of image displacement in the present embodiment is as follows:
with the correlation operations a, ##EQU6## and, with the correlation operations b, ##EQU7##
As described above, the present invention performs a focus detect operation using the correlation operations a greater in the detectable range of defocus than the correlation operations b when the focus detection is impossible with the latter, making the focus detection possible even with subjects for which the amount of defocus is large.
Moreover, when a subject is in low luminance, the focus is detected with the correlation operations a having a greater detectable range of defocus, making the focus detection possible even with subjects for which the amount of defocus is large.
Furthermore, when a subject is irradiated with assist light for focus detection, the focus detection is performed with the correlation operations a, making the focus detection possible even with subjects for which the amount of defocus is large.
According to the present invention, therefore, an automatic focus adjusting device can be provided which can reduce the time required to detect the focus without using a low contrast scan too much even when the focus detection is impossible, allows the focus detection even with subjects which are in low luminance and for which the amount of defocus is large, and allows the focus detection even with subjects for which the amount of defocus is large when they are in low luminance and require to be irradiated with assist light for focus detection.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, and representative devices shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. | An automatic focus adjusting device adapted to detect focus information of an objective lens on the basis of two images of a subject, comprises a photosensor having a number of pixels on which the two images are formed, a focus detecting area setup device for selectively setting up either of first and second focus detecting areas on said photosensor, the first focus detecting areas being initially set up and the second focus detecting areas being less in the number of pixels than the first focus detecting areas, an operation device for performing predetermined operations on outputs of the first focus detecting areas set up on the photosensor to provide focus information of the objective lens, an evaluator for evaluating whether the results of operations are proper or not, and a controller responsive to the evaluator for, when the results of operations are improper, causing the focus detecting area setup device to set up the second focus detecting areas on the photosensor and then causing the operation device to perform the operations on outputs of the second focus detecting areas. This device permits the time taken to detect the focus to be reduced without the need of making a low contrast scan even if the focus detection is impossible. | 6 |
BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates to methods of and/or means for indicating the levels of liquids and has been devised particularly though not solely for use in measuring the level of milk in a vessel.
It is an object of the present invention to provide methods of and means for measuring the level of liquid in a vessel which will at least provide the public with a useful choice.
Accordingly in one aspect the invention consists in a method of indicating the level of an electrically conducting liquid in a vessel, said method comprising the steps of allowing the liquid to rise in the vessel which contains a vertically disposed rod type resistor having an average cross sectional dimension between twenty and forty five mm and a resistance of between three and thirty two ohms per mm of length of the resistor, said method comprising the steps of allowing the liquid to rise in the vessel in a manner such that the liquid interconnects adjacent lengths of the resistor thus changing the impedance of the resistor appearing at the terminals thereof, measuring that change of impedance and converting the change of impedance into a display which indicates change of level in liquid in the vessel.
In a further aspect the invention consists in apparatus for indicating the level of an electrically conducting liquid in a vessel said apparatus comprising a rod type resistor disposed vertically in use in said vessel, said resistor having an average cross sectional dimension between twenty and forty five mm, and a resistance of between three and thirty-two ohms per mm of length of the resistor and being arranged so that increase in the level of liquid in the vessel causes some of the liquid in the vessel to interconnect adjacent lengths of the resistance wire to change the impedance thereof, means for measuring such change in impedance and display means on which change in level of liquid in the vessel is indicated.
To those skilled in the art to which this invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the description herein are purely illustrative and are not intended to be in any sense limiting.
BRIEF DESCRIPTION OF THE DRAWINGS
One preferred form of the invention will now be described with reference to the accompanying drawings in which:
FIG. 1 is an elevation of a resistor for use in apparatus according to the invention,
FIG. 2 is an enlargement of two turns of wire arranged according to FIG. 1,
FIG. 3 shows the resistor of FIG. 1 disposed in a shaped vessel.
FIG. 4 is a part figure as FIG. 1 showing different terminal connections,
FIG. 5 is a plan view of a resistor winding arrangement,
FIG. 6 is a sketch elevation of the construction shown in FIG. 5 and,
FIG. 7 is a part section of the wall of a resistor former with resistance wires shown embedded therein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, apparatus for indicating the level of an electrically conducting liquid in a vessel is provided for establishing the level of milk supplied from an individual cow for the purpose of checking on the performance of that cow.
Accordingly a rod type resistor is constructed comprising, for example, an insulating former 1 which is preferably closely wound with a fine gauge resistance wire 2. The former is of an average cross sectional dimension between twenty and forty-five mm, preferably twenty-five mm and is preferably cylindrical although other shapes which give a similar surface area may be used.
The unit described herein employs thirty-four to thirty-eight SWG nichrome wire and when such wire is wound on the twenty-five mm diameter former 1 for about four hundred mm of length, it has a total resistance of approximately four thousand ohms. The turns are closely spaced giving, for example, between three and eight turns per mm preferably five turns per mm and this gives a resistance of between one and four ohms per turn, typically about two ohms per turn. The range of resistance preferably lies between three and thirty-two ohms per mm of length.
An insulated lead 3 connects the lower end of the winding 2 to a terminal 4 and the upper end of the element 2 is connected to a terminal 5. The resistance of the element is measured by means of a bridge circuit e.g. a Marconi AC Wheatstone Bridge using alternating current at approximately 1000 Hz. Use of an alternating current prevents polarisation at the surface of the wire when immersed in milk. The bridge circuit supplies a display means in which the resistance is calibrated to give an indication of liquid level in a vessel (not shown in FIG. 1). With the apparatus described the element of 4000 ohms was reduced to an impedance of about 1500 ohms by complete immersion in milk. This reduction in impedance appearing at the terminals 4 and 5 is due to the milk, being a conducting liquid, allows current to flow from the exposed wire surface through the milk so that the turns of resistance wire below the liquid level are effectively in parallel with the body of milk.
Amongst other liquids of the same nature milk forms a sticky film which will not run off surfaces readily and thus the level indication with prior art measuring elements is usually higher than the actual liquid level once the element has been immersed and withdrawn again. The butterfat content of the milk may cause a film of fat to accumulate on the wire and thus increase the resistance of the contact between the wire and the milk. The calibration of an element not using the present invention can thus be extremely variable. In particular if a resistor comprising a single wire strand is used to measure the level of milk in a vessel the shunting of the single wire by the poorly conducting milk is very small so that extremely small changes of resistance must be determined. The present invention at least in the preferred form avoids these difficulties by the use of:
(a) The larger diameter of from twenty to forty-five mm for the former
(b) The use of a fine resistance wire which results in a high total resistance of wire but because there are many turns a relatively low change in resistance per turn, namely of the order of one to four ohms as mentioned above. The total area of the wire in contact with the milk is thus sufficiently great to allow a good low resistance connection to the milk in contact with it. A film on non-immersed turns has little effect as the milk film represents a very high resistance cross section which is in parallel with the relatively low resistance of the wire itself. Thus referring to FIG. 2 in which the resistance per turn of wire is two to four ohms approximately, if the resistor has been immersed in milk and then withdrawn or more likely the liquid level has been reduced in the vessel, a film of milk represented by the crosses in FIG. 2 will present a high parallel resistance so that the shunt effect to each turn is very small and even the shunt effect over several mm of length of film is still not great. Furthermore because there are many turns of wire on the surface of the former 1 and such turns are exposed to the milk a considerable surface area of wire is available to provide low contact resistance between the milk and the turns of wire below the level of the milk. This is brought about by the large diameter of the former 1 and by the large number of turns of wire on that former. An added effect is that because there are many turns a very small change in liquid level can be detected. Expermentation has shown that the indication of milk level was substantially unaffected by the presence of surface contamination by milk fat and liquid milk or a form of milk. Even when the surface was coated slightly with petroleum jelly the indication remained correct. Two coats of polyurethane spray were necessary to prevent the element from providing a satisfactory working result. Thus the advantages of the invention stem from:
(a) The use of a large diameter former providing a long length of resistance wire to make contact with the milk in which it is immersed, results in a large contact area and even though the unit contact resistance between the wire and the milk may be high, the large total contact area results in a low resistance connection, to a thick (say 10 mm) layer or annulus of milk around the rod type resistor.
(b) At the same time the resistance of individual turns of the element is very low (one to four ohms) so that the resistance of a ring of milk between wires over the distance of one turn i.e. in the film has little effect as the milk represents a very high resistance due to its small cross section and this high resistance is in parallel with the one to four ohms of the turn of wire.
(c) The large area of resistance wire exposed to the milk provides a low "resistance of contact" to the milk because
1. It provides a large area contact and
2. The resistance of the metal to unit area is quite low. Provided the vessel containing the milk is of great enough cross section to provide a thick, say 10 mm, layer or annulus of milk around the resistor, the parallel resistance of that body of milk is low enough to reduce the effective resistance of that portion of the resistor immersed in the milk by approximately 70%. This would not be the same with a single stand or narrow diameter element or a small number of turns of wire widely spaced on a narrow diameter former.
The effects of the invention are augmented by the use of an alternating current in the element. This alternating current has probably two effects, firstly it inhibits polarisation effects on the milk and secondly there is probably a capacitive coupling between the wires and the liquid even in the presence of a thin film of butterfat or other milk material. Thus there is a change in impedance of the resistor rather than a change in resistance only.
Where the liquid being measured (such as milk) varies in conductivity over a small range the resistance change with immersion will be affected by the conductivity to a small degree. If necessary this can be corrected by detecting the conductivity of the liquid and using this as the basis to suitably adjust the electrical or electronic measuring or converting system. Thus referring to FIG. 4 it is possible to provide two small conducting terminals for example, stainless steel studs 8 & 9 at a lower end of the resistance element former 1. One of these studs 8 is connected to the lower end of the resistance element and the other stud 9 is connected to a separate insulated lead to a terminal 10 and thence to the measuring system. An added advantage of this conductivity sensing system is the capability of using it to control an indicator system for monitoring the conductivity of the liquid. It can then be arranged, for example, to give an indication of cell count (mastitis level) as conductivity of milk may be directly related to mastitis levels. In regard to the detection of mastitis reference should be made to our New Zealand Pat. Nos. 180087 and 188810, respectively corresponding to U.S. Pat. Nos. 4,156,179 and U.S. .[.application No. 982..]. .Iadd.Pat. No. 4,309,660, issued Jan. 5, 1982. .Iaddend.
Because the change in resistance with immersion departs from linear relationship when very little of the resistance element is immersed, it is necessary or desirable to make a correction near the zero level.
Where the level is being used to measure volume of liquid, this can be done in various ways.
1. By shaping the resistance element former to give a change in resistance per unit length,
2. By varying the spacing of the resistance element winding at the lower end,
3. By shaping the containing vessel to alter relationship between volume and depth of liquid. The method described in item 3 above is the most easily applied and is illustrated in FIG. 4. Where the containing vessel 11 is provided with frustums of cones 12 and 13 having different slopes so that the liquid level rises more rapidly in the lower section 13 than in the upper section 12. The taper profiles are determined experimentally.
It will be apparent from the foregoing that the very fine wire with which the resistor is wound is somewhat fragile and therefore needs some protection. It is also necessary to provide a resistance element with a smooth surface without irregularities which could be difficult to clean and could provide areas for bacteria to collect. In FIGS. 5 & 6 there is illustrated a suitable winding machine comprising a frame 20 and a drive mechanism (not shown) driving a shaft 21 which rotates the former 1. The wire is led through a guide and tensioning means 22 which is moved along the length of the former 1 by lead screw gears 23 driving a lead screw 24 to give the desired pitch to the wire. An ultrasonic horn 25 is arranged to feed ultrasonic sound energy onto the wire where it first contacts the former which is, for example, made of a material such as polysulfone or polycarbonate. The wire heats and softens the former on making contact therewith. A fixed supporting anvil 26 is mounted below the ultrasonic horn 25 and this is made of a suitable energy absorbing material such as high density polyethylene. The effect of the ultrasonic horn is illustrated in FIG. 7 where previously wound turns 27 of wire are shown embedded in the former 1 and a turn 28 is shown above the level of the former 1 but with the former 1 softened therearound so that by the application of tension applied by the guide and tensioning means 22 the wire is pulled in to the surface of the former so that while an adequate surface area 29 is provided to enable the action of the invention to take place, yet the wire is adequately protected against washing or other procedures likely to cause damage thereto and the surface is relatively smooth for washing.
As mentioned above the vessel 11 is a flask of a milk meter such as the Waikato Mark III milk meter manufactured by AHI Plastic Moulding Company. The dimensions of the flask are not critical but of course will have an effect on the accuracy of measuring the volume of liquid. It is preferable that the walls of the vessel 11 are not closer than 10 mm to the wire on the former 1. Beyond this there is no real limit to the distance of the walls of the vessel from the former 1 except as stated that the greater this distance the more volume there will be for a given change of height and thus as stated the accuracy will be affected.
The present invention provides a simple interface between a standard milking system by providing means to give an electrical signal in proportion to the depth of milk in a flask or vessel which reflects a proportion of the total output from a particular cow. Previous attempts have been made in this regard on a number of occasions with varying degrees of success. | A wire wound resistor is vertically disposed in a vessel. The resistor has a former of between 20 mm and 45 mm diameter and resistance wire of a resistance of between 1 and 4 ohms per turn connected in the circuit of an A.C. bridge-circuit. Impedance change is indicated on a display unit calibrated to indicate the change in level of liquid e.g. milk in the vessel. The resistance wire is laid on the former by applying ultrasonic sound energy to soften the former which is of polysulfone or polycarbonate and the wire embedded in the softened former material. The vessel is shaped at the lower end to assist in giving linear readings when the level of liquid is low. | 6 |
RELATED APPLICATION
[0001] The present application is a continuation-in part of U.S. patent application Ser. No. 09/604,989 filed on Jun. 28, 2000 the disclosure of which is being incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to the field of analog and digital integrated circuits.
BACKGROUND OF THE INVENTION
[0003] It is desirable that analog and digital integrated circuits use as small an area of silicon as possible to reduce costs while maintaining high precision. The precision of eliminating circuits containing defects is excellent when the silicon wafers are sorted. However, this precision may deteriorate during the subsequent encapsulation step.
[0004] By way of example, offset voltages in an operational amplifier are on the order of 2 mV during wafer sorting which, after adjustment, are brought back down to 1 mV. However, packaging or encapsulation creates an additional shift bringing the final offset voltage back to 1.5 mV.
[0005] For a voltage reference or voltage regulator, the precision during wafer sorting is 0.8%, which is reduced to 0.2% after adjustment. As in the case of an amplifier, packaging introduces a shift bringing the final precision to 0.5%.
SUMMARY OF THE INVENTION
[0006] An object of the present invention is to adjust integrated circuits after they have been packaged, especially standard low-cost integrated circuits produced in high volume. A very high precision is to be obtained, which is at least equal to that obtained after adjustment during wafer sorting.
[0007] According to one aspect of the invention, the integrated electronic circuit comprises a resistor to be adjusted, an adjustment element mounted in parallel with the resistor to be adjusted, and at least one control transistor mounted between the adjustment element and a ground contact. The adjustment element comprises a MOS transistor, a first resistor placed between the substrate and the source of the MOS transistor, and a second resistor and a diode which are placed in series between the substrate and the drain. Both the gate and the source are short-circuited so that application of a voltage between the drain and the source biases the base/emitter junction of the parasitic bipolar transistor of the MOS transistor.
[0008] A breakdown of the MOS transistor is caused by an avalanche of the drain/substrate junction, an irreversible breakdown of the drain/substrate junction and a short circuit between the drain and the source. The element forms a resistor whose value is determined by the current due to the voltage.
[0009] A resistor may thus be adjusted independently of ground. In one embodiment of the invention, the circuit comprises a resistor in series with the resistor to be adjusted. The resistor includes a common terminal with the adjustment element. In one embodiment of the invention, the resistor to be adjusted is mounted with one terminal at a floating potential and another terminal is connected to the supply contact. In one embodiment of the invention, the control transistor is an NMOS transistor.
[0010] In one advantageous embodiment of the invention, the circuit comprises a first control transistor mounted between a supply contact and the adjustment element. A second control transistor is mounted between the adjustment element and a ground contact.
[0011] A resistor may thus be adjusted independently of ground and of the supply. In one embodiment of the invention, the resistor to be adjusted is mounted with two terminals at a floating potential. In one embodiment of the invention, the resistor to be adjusted is mounted with one terminal at a floating potential and another terminal is connected to the supply contact or to the ground contact. In one embodiment of the invention, the first control transistor is a PMOS transistor.
[0012] The second control transistor may be an NMOS transistor. The MOS transistor of the adjustment element may also be an NMOS transistor. However, a PMOS transistor may be used. Advantageously, the MOS transistor of the adjustment element includes an isolated structure. In one embodiment of the invention, the MOS transistor of the adjustment element is surrounded by a ring of p+-type conductivity. The ring may be surrounded by a well having a distance of greater than or equal to 20 μm.
[0013] In one mode of implementation of the invention, the application of a voltage between the drain and the source takes place before the circuit is encapsulated. In a preferred mode of implementation of the invention, the application of a voltage between the drain and the source takes place after encapsulating the circuit. The breakdown of the MOS transistor may be induced via the existing pins of the integrated circuit: ground, supply, input(s) and output(s). The voltage may be less than 10 volts, and is preferably less than 9 volts. The breakdown current may be less than 2 mA.
[0014] The base of the parasitic bipolar transistor is formed by the substrate, the collector is formed by the drain of the MOS transistor, and the emitter is formed by the source of the MOS transistor. The diode may be connected in such a way that it allows a current to flow from the drain to the substrate.
[0015] The present invention also provides a device for inducing the breakdown of a circuit as described above. The device comprises an analog/digital converter for the voltage applied to each input of the device, and generating means for generating a voltage for controlling a switch. The generating means is connected to the output of the converter, and a switch which is controlled by the generating means has one terminal connected to a supply and another terminal to be connected to the circuit.
[0016] Advantageously, the device comprises a reversible turn-off means capable of acting on the generating means. Advantageously, the device comprises an irreversible turn-off means capable of acting on the generating means. The turn-off means comprises a circuit that is able to breakdown. This turn-off means may be capable of turning off all the switches.
[0017] The circuit may comprise a diode such as a Zener diode, for example, or a transistor such as a MOS transistor, for example. The circuit may comprise a first resistor between the substrate and the source of a MOS transistor, and a second resistor and a diode in series between the substrate and the drain. The gate and the source are short-circuited so that application of a voltage between the drain and the source causes the base/emitter junction of the parasitic bipolar transistor of the MOS transistor to be biased. The MOS transistor breaks down by an avalanche of the drain/substrate junction, an irreversible breakdown of the drain/substrate junction and a short circuit between the drain and the source. The component forms a resistor having a value determined by the current due to the voltage.
[0018] The invention therefore makes it possible to provide standard integrated circuits with enhanced precision. The use of a so-called “snap-back” MOS transistor makes it possible to obtain a short circuit, and therefore to obtain a resistor within an integrated circuit after it has been encapsulated by acting on the existing pins of the integrated circuit. The component thus produced occupies only a small area on a silicon wafer since it comprises only one MOS transistor.
[0019] The fact that the gate and the source of the MOS transistor are short-circuited insures that it is permanently turned off, and prevents it from having any influence on the operation of the adjacent electronic circuits. Before breakdown, the component is like a turned-off MOS transistor. The diode makes it possible to avoid a leakage current during steady-state operation in those parts of the circuit to be adjusted, which in general, are operating at a voltage of a few millivolts. More generally, these parts of the circuit operate at a voltage below the threshold voltage of the diode.
[0020] The invention draws benefit from a natural characteristic of MOS transistors, which is to have parasitic components, particularly a bipolar transistor. In some configurations, these parasitic components are harmful. During electrostatic discharges circuits may be seriously damaged by the parasitic transistor being turned on.
[0021] On the other hand, the invention uses the parasitic bipolar transistor of the MOS transistor to make a short circuit to obtain a resistor having a predetermined value between the drain and the source of the MOS transistor. That is, between the collector and the emitter of the parasitic bipolar transistor. This component may be regarded as an anti-fuse. This is because a fuse is a closed circuit in the normal state and an open circuit after breakdown. Here, the component is an open circuit before breakdown (i.e., a turned-off MOS), and a closed circuit after breakdown with a low residual resistance value.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The present invention will be more clearly understood on studying the detailed description of a few embodiments taken as non-limiting examples and illustrated by the appended drawings, in which:
[0023] [0023]FIG. 1 is a characteristic curve on the operation of an NMOS transistor in accordance with the present invention;
[0024] [0024]FIG. 2 is a cross-sectional view of a MOS transistor in accordance with the present invention;
[0025] [0025]FIG. 3 is a diagram of a component according to the present invention with a MOS transistor and its parasitic bipolar transistor;
[0026] [0026]FIG. 4 is a diagram showing the component according to the present invention provided with a breakdown inducible component;
[0027] [0027]FIG. 5 is a diagram showing an example of how the components according to the present invention are used; and
[0028] [0028]FIG. 6 is a diagram of another embodiment of the component provided with a breakdown inducible component illustrated in FIG. 4.
[0029] [0029]FIG. 7 is a diagram of a circuit according to one aspect of the present invention;
[0030] [0030]FIG. 8 is a diagram of a circuit according to another aspect of the present invention; and
[0031] [0031]FIG. 9 is a top view of a MOS transistor used in the component illustrated in FIG. 8.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] As may be seen in FIG. 1, in which the drain voltage is plotted on the x-axis and the drain current is plotted on the y-axis, an NMOS transistor has four operating regions. Region 1 is a conventional linear operation of a MOS transistor. Region 2 is operation in a saturated mode, in which the current changes only very slightly with voltage. Region 3 is called the avalanche region that includes a weakening of the drain/substrate junction caused by an avalanche breakdown of the junction. Region 4 is conduction of the parasitic bipolar transistor with a first breakdown labeled 5 on the curve which is reversible, and a second breakdown labeled 6 on the curve which is destructive, and therefore irreversible.
[0033] Beyond the second breakdown 6 , the current increases extremely rapidly with voltage. The slope of the curve is almost vertical. This breakdown process, also called a second breakdown, is irreversible. Beyond the breakdown 5 , called snap-back, the curve shows a decrease in the resistance of the MOS transistor. For an approximately constant drain voltage, the current increases. The choice of the breakdown current makes it possible to determine, to a certain extent, the value of the resistor of the MOS transistor after breakdown 6 . This is under normal operating conditions.
[0034] [0034]FIG. 2 shows the structure of the various parts of the MOS transistor. The MOS transistor comprises a drain 8 , a source 9 and a gate 10 which are formed on a substrate 11 . Present in the substrate 11 is a parasitic bipolar transistor 12 whose collector is formed by the drain 8 , whose emitter is formed by the source 9 and whose base is formed by the substrate 11 . The distance separating the active base (between the drain and the source) and the base contact is modeled by a substrate resistor 13 . A current source 14 between the resistor 13 and drain is used to model the natural characteristics of the MOS transistor.
[0035] In the diagram according to the present invention illustrated in FIG. 3, the substrate 11 is connected to the drain 8 via a resistor 28 and a diode 15 . The diode 15 allows a current to flow from the drain 8 to the substrate 11 , but prevents it from flowing in the opposite direction. A resistor 16 is between the base of the parasitic bipolar transistor 12 and the source 9 . The source is connected to the emitter of the parasitic bipolar transistor 12 . The resistor 16 makes it possible to achieve a good equipotential for the base/emitter junction of the parasitic bipolar transistor.
[0036] In the steady state and in the absence of a breakdown, the circuit portion in parallel with the adjustment device is subjected to a voltage. The voltage may be, for example, on the order of 100 mV. This is below the threshold voltage of the diode 15 , which prevents the appearance of a leakage current from the drain to ground. The resistor 16 makes it possible to draw off some of the possible leakage current from the diode 15 so that the base current of the parasitic bipolar transistor is as low as possible.
[0037] The drain 8 is connected to a first supply voltage, while the source 9 and the gate 10 are short-circuited and connected to ground. By applying a high voltage between the collector and the emitter, this voltage is divided between the two junctions. The emitter-base junction is slightly forward-biased, and electrons are injected into the base, and after passing through the base add to the leakage current of the base-collector junction. Thus, by biasing the substrate, the base-emitter junction is turned on without there having been a total avalanche of the collector-base junction. The breakdown phenomenon then occurs. By adding current to the leakage current of the base-collector junction makes it possible to reduce both the breakdown voltage and the breakdown current of the component.
[0038] The component reverts to a second, irreversible breakdown mode which results in a heat-up and destruction of the crystal lattice. Next, a polysilicon resistor is created between the drain and the source. To initiate the avalanche phenomenon, a large enough voltage must be imposed on the drain. This voltage depends on the doping characteristics and on the gain of the parasitic bipolar transistor, and is proportional to the square of the electric field.
[0039] By way of example, tests have been carried out in HF4 CMOS technology with an NMOS transistor whose channel has the following dimensions: width=1 μm, and length=0.7 μm. The source is grounded and a voltage ramp rising up to 9.5 volts is applied to the drain with current limitation. For a 2 mA collector current, a post-breakdown resistance of 11 ohms is obtained with a base current in the region of 100 μA, and in all cases between 60 and 160 μA.
[0040] It is suitable to use a voltage ramp with a steep slope, which makes it possible to reduce the duration of the breakdown process and to insure a satisfactory breakdown. Within a certain range, the value of the resistor is independent of the collector current. Thus, it is possible to create the breakdown with a voltage of less than 10 volts, which does not carry the risk of damaging the integrated circuit in HF4CMOS technology, or in other technologies that withstand only low voltages.
[0041] Of course, what has been described with an NMOS transistor also applies to the case of the PMOS transistor. More generally, the invention makes it possible to obtain a breakdown voltage compatible with the voltage limit of the integrated circuit, with the voltage limit being based upon the technology of the integrated circuit.
[0042] It is particularly advantageous to use transistors whose channel is as short as possible. The shorter the channel the lower the breakdown voltage. This is on account of the increase in the drain current and the increase in the number of electron-hole pairs generated for a constant channel width. Decreasing the channel width results in a decrease in the voltage and of the current of the second breakdown 6 illustrated in FIG. 1. Even if the width of the channel does not fall within the voltage of the first breakdown 5 , a reduced width will increase the thermal effect of the second breakdown 6 since the field lines are then more unidirectional. This implies a reduction in the coupling of the second breakdown. It is therefore particularly advantageous to use MOS transistors having small dimensions.
[0043] The creation of the resistor by the breakdown of the MOS transistor in an integrated circuit after encapsulation has to take place via the conventional pins used for the inputs and outputs, and the supply and ground terminals without providing additional pins. Providing additional pins would be expensive, and subsequently, redundant. It is therefore possible to apply a constant positive voltage on the supply, and to apply a negative voltage ramp to ground with a current limitation to create the desired resistor. Such a resistor may be placed, for example, in the “feet” of a differential amplifier which, in general, forms the input stage of an operational amplifier. The term “foot” should be understood as meaning the active-load emitter terminal of the differential amplifier.
[0044] The invention thus makes it possible to take advantage of a natural characteristic of MOS transistors that is normally regarded as a drawback. This is done to create an integrated resistor to obtain integrated circuits produced in very high volume with a high precision.
[0045] The breakdown of the MOS transistor in an integrated circuit after encapsulation requires suitable induction, as well as means for inhibiting the breakdown before encapsulation during wafer sorting. For this purpose, a structure as illustrated in FIG. 4 may be provided. The breakdown inducible component 17 comprises an NMOS transistor 18 , a diode 15 and two resistors 14 and 16 . These elements are placed, as explained above, for a breakdown with prebiasing of the base-emitter junction of the parasitic bipolar transistor. Using the induction device, it is also conceivable to induce breakdown in a MOS transistor whose substrate is connected to ground. This requires a higher breakdown voltage of about 16 volts, or else a Zener diode of even higher breakdown voltage of about 24 volts, for example.
[0046] The breakdown inducible component 17 (or the MOS transistor or the Zener diode) is connected to ground and to the drain of a PMOS transistor 19 . The source of the PMOS transistor 19 is connected to a supply terminal, and its gate is connected to a generator circuit or generating means 20 for generating a control voltage. Other types of switches may be used instead of the transistor 19 . The generating means 20 comprises a plurality of outputs S 1 , S 2 , . . . S n , each connected to the control input of a switch capable of inducing the breakdown of a breakdown inducible component 17 . For the sake of clarity, only a single component 17 whose breakdown is induced via the output S 1 has been shown in FIG. 4.
[0047] The generating means 20 is connected to a terminal 21 accessible during wafer sorting before encapsulation. This makes it possible to inhibit the generating means 20 by applying a predetermined voltage to temporarily prevent breakdown of a breakdown inducible component 17 , which is connected to one of the outputs S 1 , S 2 , . . . S n .
[0048] The generating means 20 comprises an input 22 connected to a breakdown inducible component 23 which may be of the same type as the breakdown inducible component 17 , or a MOS transistor or a Zener diode. The breakdown inducible component 23 is also connected to ground. The breakdown of the component 23 brings the voltage on the input 22 to that on the ground terminal. This prevents breakdown of the breakdown inducible component 17 connected to one of the outputs S 1 , S 2 , . . . S n . This operation is carried out after the adjustment, which is carried out after encapsulation. This prevents any subsequent loss of adjustment by breakdown of one of the breakdown inducible components 17 connected to one of the outputs S 1 , S 2 . . . S n , especially by the user of the integrated circuit.
[0049] Preferably, the reversible inhibition terminal 21 is formed on the irreversible inhibition input 22 , thereby making it possible to save space. During the wafer sorting, a given voltage is applied to the terminal 21 . This given voltage is capable of temporarily preventing the breakdown of a breakdown inducible component 17 . In addition, this temporarily prevents the breakdown of the breakdown inducible component 23 since the PMOS transistor 19 forming a switch of the component 23 is turned off.
[0050] After encapsulation, the terminal 21 is no longer accessible and only a particular combination of voltages applied to the pins of the package containing the structure of FIG. 4 may cause the breakdown of the breakdown inducible component 23 . The breakdown of the component 23 causes all the outputs S 1 , S 2 , . . . S n to go to a high level, hence turning off the MOS transistor 19 with almost zero consumption. This prevents the breakdown of component 17 .
[0051] The generating means 20 is connected via two inputs 24 , 25 to two outputs E 1 and E 2 of an analog-digital converter 26 . The analog-digital converter 26 has two inputs E+, E− which are connected, for example, to the inputs of an operational amplifier to be balanced after encapsulation.
[0052] The two inputs E+, E− each receive an analog voltage between 0 and 10 volts, for example. The outputs S 1 , S 2 , . . . S n have binary output levels, one cap-able of turning off the transistor 19 and the other of turning it on, and hence inducing breakdown of the breakdown inducible component 17 connected to the corresponding output.
[0053] The analog-digital converter 26 carries out multiplexing with the following truth table:
E + E − E1 E2 B B 0 0 B A 0 1 A B 1 0 A A 1 1
[0054] With A<Vdd-Vtp and B>Vdd-Vtp, Vdd is the supply voltage and Vtp is the threshold voltage of the transistors of the analog-digital converter 26 , for example, of the PMOS type. Thus, with two inputs it is possible to make four combinations.
[0055] The following truth table makes it possible to generate the control signals for the breakdown inducing transistors 19 via the generating means 20 :
E + E − E1 E2 S1 S2 S3 S4 B B 0 0 0 1 1 1 B A 0 1 1 0 1 1 A B 1 0 1 1 0 1 A A 1 1 1 1 1 0
[0056] To be able to initiate breakdown in a number of breakdown inducible components greater than four, an analog-digital converter 26 capable of interpreting a higher number of voltage levels is used. The analog-digital converter 26 comprises at least two MOS transistors whose gates are connected to one of the inputs E+, E−. The sources are connected to the Vdd supply voltage and the drains forming the outputs are each connected to a current source.
[0057] These MOS transistors have different width-to-length ratios so that they switch for different and staggered gate voltages. In the case of three MOS transistors per input E+ and E−, switch voltages of −1.3 volts, −2.2 volts and −3.5 volts with respect to the supply voltage Vdd may be provided. The dual structure is possible. The switch voltages are, in this case, referenced with respect to ground.
[0058] In the case of a circuit to be adjusted which has a single input, the four regions with three structures in parallel makes it possible to initiate breakdown in four breakdown inducible components. One of which will be able to serve for the irreversible inhibition, such as for the component 23 in FIG. 4. In the case of a circuit to be adjusted which has two inputs, the four regions per input make it possible to initiate breakdown in six breakdown inducible components. One of which will be able to serve for the irreversible inhibition. In general, the number of components able to be initiated is equal to the number of inputs multiplied by the number of switching (MOS transistors) structures in parallel on each input increased by the number 1.
[0059] [0059]FIG. 5 illustrates an example of an integrated circuit for adjusting the offset voltage of an operational amplifier comprising a cascode circuit as an input. Only the resistors R casc1 and R casc2 of the cascode circuit are illustrated. These resistors respectively correspond to the inverting and non-inverting inputs of the amplifier. Two parallel branches are connected in parallel with the resistor R casc1 , and three parallel branches are connected in parallel with the resistor R casc2 .
[0060] The five branches are of similar construction. One branch comprises, in series, a resistor, R 1 , R 2 , R 3 , R 4 or R 5 , and a breakdown inducible structure 27 comprising a breakdown inducible component and its associated initiating switch. Each resistor R 1 , R 2 , R 3 , R 4 , R 5 is in series with a breakdown inducible component but not with the corresponding initiating switch. By selectively choosing the values of the resistors R 1 , R 2 , R 3 , R 4 , R 5 it is possible to obtain a wide range of resistance values after breakdown, R bd1 and R bd2 , on each input of the amplifier. It is also possible to correct adjustment defects in the offset voltage in a precise manner and over a wide range. Thus:
R bd1 =1/(1/ R casc1 +1/( R 1 or 4)+1/ ( R 2 or 4)+1/( R 3 or 4)),
R bd2 =1/(1/ R casc2 +1/( R 4 or 4)+1/( R 5 or 4)).
[0061] Each branch thus has an infinite resistance, denoted by 4 , if its structure 27 has not undergone breakdown. Each branch has a resistance equal to the sum of the resistance of the structure 27 that has undergone breakdown, e.g., 11 ohms, and of the resistance of the resistor R 1 , R 2 , R 3 , R 4 , R 5 . The resistance is approximately equal to the resistance of the resistor R 1 , R 2 , R 3 , R 4 , R 5 which is of a markedly higher value, i.e., on the order of a few kilohms or a few tens of kilohms.
[0062] The invention provides the benefit of an induction device for components which are able to breakdown. The device is inexpensive, small in size, consumes little power and is very reliable. The breakdown is established after the circuit has been encapsulated, and is induced via the conventional pins, such as the ground/supply pins, and the input/output pins. The breakdown requires no additional pins.
[0063] In the variation illustrated in FIG. 6, a module 30 is connected to the generating means 20 to measure the parameter to be adjusted, such as the voltage Vio for an operational amplifier mounted as a comparator. This may be performed in a circuit-adjustment phase during a final sorting operation.
[0064] The module 30 comprises a plurality of n diodes 31 connected in series between a supply voltage and a resistor 32 connected to ground. A current source 33 is connected in series with an NMOS transistor 34 between a supply voltage and ground. The gate of the transistor 34 is connected to the common point between the resistor 32 and the series of n diodes 31 .
[0065] For a standard supply voltage, such as 5 volts, for example, the transistor 34 is off. Hence, a logic 1 level is applied to terminal 21 , thereby inhibiting any selection of a component 17 . A higher voltage, which depends on the number n of diodes 31 , turns the transistor 34 on. Hence, a logic 0 level on terminal 21 and the possibility of selecting a component 17 , the selection of which may result in voltage oscillations in the generating means 20 , are necessary for an accurate voltage measurement.
[0066] The module 30 makes it possible to inhibit the generating means 20 , and therefore, turn off the transistor 19 for controlling the breakdown inducible component 17 . The generating means 20 is inhibited for a voltage which is always less than or equal to the nominal supply voltage of the circuit. Above the voltage fixed by the module 30 , the transistor is turned on, and consequently, so is the breakdown inducible component 17 just before reaching the breakdown voltage.
[0067] The module 30 therefore makes it possible, first, to measure the parameter to be adjusted for supply voltages less than the switching voltage of the module 30 , and second, to adjust the parameter for the supply voltage greater than the voltage of the module 30 . In the industrial phase, it is difficult without the module 30 to measure the parameter accurately since, with the adjustment device being active, the measurement is falsified by the selection of a structure.
[0068] At the end of the final sorting, with the adjustment having been made, the irreversible inhibition process is carried out by the breakdown inducible component 23 which turns off, once and for all, the adjustment structures. Thus, it is possible to measure the parameter to be adjusted before the irreversible inhibition. The module 30 makes it possible to turn off the components 17 .
[0069] In the embodiment illustrated in FIG. 7, a circuit comprises an adjustment component 17 , a resistor 35 to be adjusted, a supply contact 36 accessible during adjustment, a resistor 37 , an NMOS type control transistor 38 , a ground contact 39 accessible during adjustment and a control input 40 connected to the gate of the control transistor 38 . The resistor 35 to be adjusted has one terminal connected to the supply contact 36 , and another terminal connected to the resistor 37 and to the rest of the circuit (not shown), with which the resistor to be adjusted will interact during normal operation of the circuit after adjustment and packaging.
[0070] The component 17 is mounted between the supply contact 36 and the drain of the control transistor 38 . The resistor 37 is mounted between the resistor 35 to be adjusted and the drain of the control transistor 38 . In other words, the resistor 35 to be adjusted and the resistor 37 are mounted in parallel with component 17 . The source of the control transistor 38 is connected to the ground contact 39 . The component 17 as illustrated in FIGS. 4 and 6 includes the source and the gate of its MOS transistor 18 connected to the drain of the control transistor 38 and its drain connected to the supply contact 36 . The circuit is well suited to the adjustment of one or more resistors which do not have any direct connection to the ground contact 39 and are connected to the supply contact 36 .
[0071] The embodiment illustrated in FIG. 8 is similar to the previous one except for another PMOS type control transistor 41 which is placed between the supply contact 36 and the component 17 , with its source connected to the supply contact 36 and its drain connected to the component 17 . A resistor 42 is placed between a first terminal of the resistor 35 to be adjusted and the drain of the control transistor 41 . The second terminal of the resistor 35 to be adjusted is connected to the drain of the control transistor 38 .
[0072] A resistor 43 is placed between the first terminal of the resistor 35 to be adjusted and the supply contact 36 . A resistor 44 is placed between the second terminal of the resistor 35 to be adjusted and the ground contact 39 . The gate of the control transistor 41 is connected to the control input 40 . An inverter 45 is mounted between the control input 40 and the gate of the control transistor 38 .
[0073] The circuit is well suited to the adjustment of one or more resistors having no direct connection either to the ground contact 39 or to the supply contact 36 . The circuit may also serve for adjusting one or more resistors provided with direct connections to the ground contact 39 and/or to the supply contact 36 .
[0074] By appropriately dimensioning the control transistors it is possible to optimize the semiconductor wafer area used. Since the mobility of electrons is greater than that of holes, a control transistor 41 may be chosen having a resistance R on three times greater than that of the control transistor 38 , such as 30 Ω and 10 Ω, for example. Moreover, it is preferable to use an isolated-type MOS transistor for the component 17 to prevent the currents from being modified by the substrate resistance of a structure which is not isolated.
[0075] As illustrated in FIG. 9, the MOS transistor of the component 17 is surrounded by a ring 46 of p+-type conductivity. Contact with this p+-type conductivity ring 46 takes place on the drain side to facilitate breakdown of the MOS transistor 17 , and the spatial dimensions of the substrate 47 are substantially increased, such as by 20 μm, for example. Thus, the current gain of the parasitic bipolar transistor associated with the MOS transistor 17 , the base of which is connected to the well, the collector of which is connected to the connection contacts of a buried layer (n iso ) and the emitter of which is connected to the source of the MOS transistor is decreased. The drawbacks of using an isolated structure are thus avoided. | An integrated circuit includes an adjustment resistor, and at least one control transistor connected to a first voltage reference. An adjustment element is connected in parallel with the adjustment resistor for adjusting a combined electrical resistance of the adjustment element and the resistor. The adjustment element is connected to the control transistor, and includes a substrate, and a MOS transistor having a source, a drain, and a gate on the substrate. The MOS transistor defines a parasitic bipolar transistor with the substrate. The adjustment element further includes a first resistor connected between the substrate and the source, and a second resistor is connected between the substrate and the drain. A diode is connected in series with the second resistor between the substrate and the drain. The gate and the source of the MOS transistor are connected together with the MOS transistor being broken down so that the adjustable element forms an electrical resistance. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is related to a U.S. Design Patent Application (Our Docket No. 223620US51) filed concurrently herewith.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to machine elements and mechanisms generally, but more particularly to small but strong plastic gear boxes with reduction drive assemblies inside.
[0004] 2. Description of the Related Art
[0005] U.S. Pat. No. 5,598,746 to Chen describes a transmission assembly having a plastic box and cover employing locating posts. U.S. Pat. No. 5,737,968 to Hardey et al. discloses a gear motor assembly with a three-part molded housing having plural cylindrical connector bosses which may be ultrasonically welded together. U.S. Pat. No. 4,825,727 to Komuro relates to a speed reducer having a gear mounting plate formed with ribs for noise reduction. These three prior art devices appear to be most relevant to the gear box of the present invention, in the applicant's view.
[0006] U.S. Pat. No. 2,908,180 to Swenson reveals a gear reduction unit for a fractional horsepower motor comprising a stationary stub shaft and a rotatable work shaft with a train of intermeshing reduction gears floating free on both shafts to drive a final fixed output gear on a power shaft in the last stage. Power is received from a motor pinion driving a floating gear on a power shaft in the first or input state. U.S. Pat. No. 5,038,629 to Takimoto discloses a drive transmission mechanism having plural stages of gear reduction. Plural gears are supported by the same shaft and are rotatable relative to each other. For an example, see column 4 at lines 22-27. European Patent No. 617,213 to Masumi refers to a motorized actuator having a train of reduction gears. Plural supporting shafts each have more than one gear thereon and are able to rotate relative to one another. See column 5, line 56, through column 6, line 39. These three earlier patents appear to be the most relevant references in relation to the reduction drive assembly of the present invention, in the applicant's view.
[0007] An exemplary prior art device is illustrated in a cross-sectional view in FIG. 1. A gear box 10 has a main body 11 made of die cast zinc metal and is attached to a direct current (D.C.) motor 12 which drives a small input gear 14 held on an input shaft 16 . The small input gear 14 drives a first cluster gear 18 which rotates with a first pinion gear 20 that, in turn, drives a second cluster gear 22 which rotates with a second pinion gear 24 . The first cluster gear 18 and the first pinion gear 20 are mounted on a first shaft 26 while the second cluster gear 22 and the second pinion gear 24 are mounted on a second shaft 28 . The first shaft 26 and the second shaft 28 are topped by spacers 30 and 32 , respectively, that separate the shafts 26 and 28 from a cover 34 which is connected by screws (not shown) to the main body 11 and which is also made of the same die cast zinc metal as the main body 11 . The second pinion gear 24 drives a third cluster gear 36 which rotates with a third pinion gear 38 that, in turn, drives a large output gear 40 mounted on an output shaft 42 . A first collar 44 secures one end of the output shaft 42 to the main body 11 while a second collar 46 secures an opposite end of the output shaft 42 to the cover 34 . A small, flat sheet of steel is rolled to form a C-shaped pin 48 that is inserted at the opposite end of the output shaft 42 in order to spin a drum or hopper 6 holding coins or tokens in a slot machine 1 . The gear box 10 is fastened to the slot machine 1 through a wall 4 by a plurality of bolts 8 .
[0008] Although the exemplary prior art device illustrated in FIG. 1 is made of metal, it requires screws (not shown) to fix the cover 34 to the main body 11 . Thus, because the holes required for the screws weaken the solid structure of both the main body 11 and the cover 34 , the gear box 10 is not as strong as it could be if there were no screw holes therethrough.
[0009] Also, because of the positioning of the various cluster gears and pinion gears on five separate shafts, the amount of force which can be transmitted from the small input gear 14 to the large output shaft 42 is limited. Thus, it remains a problem in the prior art to produce a high torque resistant and strong screwless gear box holding a reduction gear assembly inside.
SUMMARY OF THE INVENTION
[0010] A primary object of the present invention is to provide a high torque resistant and strong screwless plastic gear box to overcome the problems existing with prior art metal gear boxes.
[0011] A secondary object of the present invention is to reduce substantially the thickness of the gear box at the output shaft.
[0012] The present invention relates generally to a plastic gear box and a reduction drive assembly for mounting in the gear box to achieve the above-stated goals. The gear box and the reduction drive assembly may be used particularly, but not exclusively, in a slot machine with a spinning drum or hopper which holds coins or tokens to be released therefrom upon receiving an electrical signal after a predetermined number of coins have been deposited into the slot machine.
[0013] The gear box includes a plastic main body and a plastic cover which is ultrasonically welded to the main body. Welding pads and surrounding tubes are provided at intervals around a periphery of the main body and the cover. Also, locating ribs are provided inside the cover of the gear box. Plural locating posts on the cover are ultrasonically welded into corresponding hollow holding tubes in the main body to increase the strength of the gear box so that it can withstand high torque levels without fracturing.
[0014] This arrangement results in an empty gear box, without the drive assembly inside, being capable of withstanding torques up to 300 inch-pounds and weights up to at least 225 pounds without breakage and without the use of any screws to retain the cover on the main body.
[0015] This main body also has acoustical chambers between outer straight walls and inner arcuate walls. The inner arcuate walls surround all of the various shafts and gears inside the main body. This double-walled construction reduces noise and provides surprising mechanical strength greater than that of any other known prior art plastic gear boxes. This characteristic of the present invention was an unexpected result for a plastic gear box resulting in strength comparable to a metal gear box.
[0016] The drive assembly mounted between the cover and the main body includes gears mounted on only three shafts instead of the five shafts of the prior art device shown in FIG. 1. Power from a D.C. motor is supplied to the gear mounted on a first input shaft. This gear, in turn, drives gears stacked on a single central shaft. The last of the central gears then drives an output gear on the output shaft.
[0017] To summarize the invention, it relates to a high torque resistant and strong screwless plastic gear box, particularly characterized by ultrasonically welded pads, locating ribs and support posts. The invention also relates to the drive assembly described above by which four of the central gears are stacked to rotate in pairs independently on a single central shaft.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] A more complete appreciation of the invention and its advantageous features will be readily understood by reference to the following detailed discussion when considered with the accompanying drawings that are briefly described below.
[0019] [0019]FIG. 1 is a cross-sectional side elevation view of a known prior art device.
[0020] [0020]FIG. 2A is a cross-sectional side elevation view of the gear box of the present invention with the internal drive assembly under a cover.
[0021] [0021]FIG. 2B is a partial top plan view taken along line 2 B- 2 B of FIG. 2A.
[0022] [0022]FIG. 3A is a bottom plan view of the main body of the gear box.
[0023] [0023]FIG. 3B is a top plan view of the main body of the gear box with the internal drive assembly removed therefrom.
[0024] [0024]FIG. 3C is a cross-sectional side elevation view taken along line 3 C- 3 C of FIG. 3B.
[0025] [0025]FIG. 4A is an underside view of the cover of the gear box.
[0026] [0026]FIG. 4B is a cross-sectional side elevation view taken along line 4 B- 4 B of FIG. 4A.
[0027] [0027]FIG. 4C is a top plan view of the cover with the main body of the gear box thereunder.
[0028] [0028]FIG. 5 is a partially cutaway cross-sectional view of the gear box with the internal drive assembly removed therefrom.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] Referring now to the drawings, like reference numerals designate identical or corresponding parts throughout the several views.
[0030] A cross-sectional view of the invention is shown in FIG. 2A. A gear box 110 has a main body 111 made of ABS plastic and is attached to a direct current (D.C.) motor 112 which turns a small input shaft 116 that carries and rotates a small input gear 114 . Teeth 115 on the small input gear 114 mesh with and drive teeth 117 on a first central gear 118 which carries and rotates with a first pinion gear 120 . This gear 120 has teeth 121 that, in turn, drive a second gear 122 which carries and rotates with a second pinion gear 124 .
[0031] The small input gear 114 is made of hard plastic while the small input shaft 116 is made of steel. The first central gear 118 is made of plastic while the first pinion gear 120 is made of steel. Both the second gear 122 and the second pinion gear 124 are formed integrally of steel. Note that the first steel pinion gear 120 and the second steel pinion gear 124 have diameters of the same size.
[0032] The first central gear 118 and the first pinion gear 120 are mounted on a single central shaft 126 while the second gear 122 and its pinion gear 124 are mounted on a second shaft 128 . The single central shaft 126 is held at one end 126 A in a first raised boss 111 A of the main body 111 and is held at its opposite end 126 B in a first raised boss 134 A of a cover 134 . Similarly, the second shaft 128 is held at one end 128 A in a second raised boss 111 B of the main body 111 and is held at its opposite end 128 B in a second raised boss 134 B of the cover 134 .
[0033] Teeth 125 on the second pinion gear 124 mesh with teeth 135 on a third gear 136 which carries and rotates with a third pinion gear 138 that has teeth 139 which, in turn, drive a large output gear 140 mounted on an output shaft 142 .
[0034] A first collar 144 of the main body 111 has a bore 144 B which surrounds a midsection of the output shaft 142 while a second collar 146 secures a nonworking end 142 B of the output shaft 142 to the cover 134 . A gap 143 is provided between the nonworking end 142 B of the output shaft 142 and a bottom 145 of the second collar 146 . A lubricant such as grease may be squirted into the gap 143 through a channel 147 bored through the cover 134 .
[0035] Both the first collar 144 and the second collar 146 are formed integrally with the main body 111 and the cover 134 , respectively. This integral formation reduces the number of parts needed for manufacturing the gear box 110 by eliminating the separate collars 44 and 46 in the prior art gear box 10 illustrated in FIG. 1.
[0036] Returning to FIG. 2A, the third gear 136 , the third pinion gear 138 , the output gear 140 , and the output shaft 142 are all made of steel. Thus, the gear assembly starts with the small plastic input gear 114 and eventually transitions to the large steel output gear 140 by the unique internal arrangement of the various reduction gears constituting the drive assembly.
[0037] At a working end 142 A of the output shaft 142 , there is a solid steel pin 148 which spins a drum or hopper 106 holding coins or tokens in a slot machine 100 . Although the solid steel pin 148 is preferred, any other suitable type of coupling may be used, such as a threaded shaft, a D-shaft, a shaft with double flat ends, etc.
[0038] So, there are three shafts, namely the central shaft 126 , the second shaft 128 and the output shaft 142 . The output shaft 142 has a longer length and a thicker diameter than the central shaft 126 and the second shaft 128 so that the output shaft 142 is able to carry the output gear 140 which is much larger than the first gear 118 , the second gear 122 , and the third gear 136 . Although the central shaft 126 and the second shaft 128 have the same length and the same diameter and each of the shafts 126 and 128 carry gears 136 and 122 , respectively, which have the same diameter, the pinion gears 138 and 124 have different diameters. However, the pinion gear 120 carried with the first central gear 118 has the same diameter as the pinion gear 124 formed integrally with the second gear 122 . Thus, although the first central gear 118 and the third gear 136 are mounted on the same central shaft 126 , these gears 118 and 136 are driven independently of each other by the input gear 114 and the second pinion gear 124 , respectively.
[0039] A bore 150 through the main body 111 allows a user to locate the one end 128 A of the second shaft 128 from outside the gear box 110 . Likewise, a concave dimple 152 in the main body 111 serves to allow the user to locate the one end 126 A of the central shaft 126 from outside the gear box 110 . However, unlike the bore 150 , the dimple 152 does not penetrate completely through an exterior surface of the main body 111 , but may be easily drilled through in order to reach the central shaft 126 , if necessary.
[0040] By engaging both the central shaft 126 through the drilled dimple 152 and the second shaft 128 through the bore 150 , the user may extract the gear box 110 from the D.C. motor 112 , if the gear box 110 cannot be removed because it is stuck in place by the D.C. motor 112 .
[0041] In FIG. 2B, there is seen a partial top plan view of the main body 111 from which the first collar 144 protrudes to retain the output shaft 142 with its working end 142 A through which the solid steel pin 148 extends.
[0042] Clearly, the solid steel pin 148 of the present invention is stronger and more torque resistant than the C-shaped pin 48 of the prior art device seen in FIG. 1. Thus, the pin 148 of the present invention is able to work harder than the weak pin 48 of the prior art device.
[0043] In FIG. 3A, there is illustrated a bottom plan view of the main body 111 of the gear box 110 . The pin 148 extends through the output shaft 142 which is surrounded at its midsection (not shown) by the first collar 144 .
[0044] There are four vertically grooved holes 158 of which only two are shown on a left side of the main body 111 . On a right side of the main body 111 , there are seen two of four heads 160 on threaded bolts 162 , not shown in FIG. 3A but seen instead in FIG. 2A, where two of the four heads 160 are also illustrated. As shown in both FIGS. 2A and 3A, a washer 164 separates each head 160 from a top 166 of a raised protuberance 168 formed integrally with the main body 111 .
[0045] As seen in FIG. 3A, the four holes 158 , of which only two are shown, are positioned on the main body 111 symmetrically and equidistantly from the output shaft 142 so that, when the bolts 162 (not shown) under the heads 160 are threaded into the holes 158 , the output shaft 142 has superior stability and maximum strength whenever the pin 148 is exerting torque to perform work.
[0046] Of course, instead of the bolts 162 seen in FIG. 2A, a plurality of other types of suitable fasteners, such as long screws, may be placed in the holes 158 to stabilize the output shaft 142 and also may be used to mount the gear box 110 securely to a wall 104 of the slot machine 100 .
[0047] Preferably, as seen in FIG. 3A, the vertically grooved holes 158 are provided with correspondingly grooved steel or brass inserts 170 which are internally threaded for receiving the bolts 162 seen in FIG. 2A.
[0048] [0048]FIG. 3B shows a top plan view of the main body 111 of the gear box 110 with the internal drive assembly and the cover 134 (not shown) removed therefrom.
[0049] The four holes 158 are positioned symmetrically and equidistantly from a center of the bore 144 B through the first collar 144 . An end view of each of a plurality of hollow holding tubes 156 is seen adjacent to each of the four holes 158 .
[0050] A plurality of inner welding pads 172 is formed integrally and is arranged along an outer periphery of the main body 111 . Each pad 172 is separated by a space from a surrounding short outer tube 174 . Each pad 172 is preferably circular and each tube 174 is preferably cylindrical in shape. However, other shapes may be used, if desired. These pads 172 are heated ultrasonically so that each pad 172 partially melts with its corresponding short tube 174 in order that the main body 111 is welded to the cover 134 , seen in FIG. 2A, to keep the gear box 110 securely sealed shut.
[0051] In FIG. 3B, thin rib walls 176 radiate from some of the short tubes 174 to an inner periphery which is made up of a plurality of arcuate wall sections 178 formed integrally inside the main body 111 . Thus, the outer periphery of the main body 111 , the short tubes 174 , the thin rib walls 176 , and the arcuate wall sections 178 together form differently shaped acoustical chambers 180 which may be full of insulating air or packed with grease for noise reduction. Note that each chamber 180 is formed integrally in the main body 111 .
[0052] The arcuate wall sections 178 together form an enclosed space within which lubricant for the drive assembly is readily retained. Because the lubricant cannot fly out of the enclosed space surrounding all of the shafts and the gears of the drive assembly while the gears are turning on the shafts, the gears have a longer work life and need to be lubricated less frequently. Within the arcuate wall sections 178 , besides the first collar 144 , there is the first raised boss 111 A and the second raised boss 111 B. A blind hole 111 C in the first raised boss 111 A receives the one end 126 A of the central shaft 126 seen in FIG. 2A while a flanged hole 111 D in the second raised boss 111 B receives the one end 128 A of the second shaft 128 , also seen in FIG. 2A.
[0053] In FIG. 3B, thick ribs 182 radiate from the first collar 144 , the first raised boss 111 A, and the second raised boss 111 B to the arcuate wall sections 178 which form an internal space for retaining the drive assembly so that no individual gear may fly away in the unlikely event that a shaft breaks and a gear slips off.
[0054] [0054]FIG. 3C shows a cross-sectional side elevation view of the main body 111 taken along line 3 C- 3 C in FIG. 3B. The curvature of three arcuate wall sections 178 is clearly illustrated throughout most of FIG. 3C. Along the left side of the main body 111 , there are seen the first collar 144 , the first raised boss 111 A, and the second raised boss 111 B. Two of the four raised protuberances 168 are also shown. Behind one of the thin rib walls 176 , there is seen in phantom lines part of one of the acoustical chambers 180 .
[0055] [0055]FIG. 4A shows the cover 134 with its underside that faces the internal drive assembly. Around the periphery of the underside, there are arranged a plurality of locating posts 154 , a plurality of welding rings 184 , and a plurality of locating ribs 186 .
[0056] Referring back to FIG. 3B, each welding ring 184 seen in FIG. 4A is fitted snugly into the space between its corresponding inner welding pad 172 and its corresponding outer short tube 174 so that, when ultrasonic radiation is applied to each combination of the ring 184 , the pad 172 and the tube 174 , the combination melts together in order to weld the cover 134 onto the main body 111 to close the gear box 110 securely.
[0057] Referring again to FIG. 3B, each locating rib 186 seen in FIG. 4A is positioned so as to snap into a corresponding acoustical chamber 180 along the outer periphery of the main body 111 to help in providing secure closure of the cover 134 over the main body 111 .
[0058] In FIG. 4A, away from the outer periphery of the cover 134 , there are arranged the second collar 146 , the first raised boss 134 A, and the second raised boss 134 B. A flanged hole 134 C in the first raised boss 134 A receives the opposite end 126 B of the central shaft 126 seen in FIG. 2A while a blind hole 134 D in the second raised boss 134 B receives the opposite end 128 B of the second shaft 128 , also seen in FIG. 2A.
[0059] In FIG. 4A, thick ribs 194 radiate from each of the second collar 146 and the bosses 134 A, 134 B to reinforce the cover 134 . The channel 147 is seen at the bottom 145 of the second collar 146 .
[0060] A circular opening 188 is provided in the cover 134 so that the input gear 114 , seen in FIG. 2A, may be inserted therethrough for meshing with the first central gear 118 , also seen in FIG. 2A.
[0061] Referring again to FIG. 4A, there is a pair of holes 190 spaced equidistantly from a center of the circular opening 188 . Each hole 190 has an internal flange 192 for retaining a head of a screw (not shown) which secures the D.C. motor 112 , seen in FIG. 2A, to a top side of the cover 134 .
[0062] [0062]FIG. 4B shows a cross-sectional side elevation view of the cover 134 taken along line 4 B- 4 B of FIG. 4A. At the top of FIG. 4B, there are seen side views of locating posts 154 , side views of the welding rings 184 , and end views of the locating ribs 186 . These locating posts 154 , welding rings 184 and locating ribs 186 are formed integrally on an inner side of the cover 134 . The second collar 146 and the bosses 134 A, 134 B are also clearly illustrated.
[0063] [0063]FIG. 4B also shows the gap 143 which receives lubricant through the channel 147 in the bottom 145 of the second collar 146 . Furthermore, there are clearly illustrated the flanged hole 134 C in the first raised boss 134 A and the blind hole 134 D in the second raised boss 134 B of the cover 134 .
[0064] A mounting pad 196 is formed integrally with the top side of the cover 134 . The mounting pad 196 holds the D.C. motor 112 , seen in FIG. 2A, by the screws (not shown) which pass through the holes 190 seen in FIG. 4A.
[0065] [0065]FIG. 4C shows a top plan view of the cover 134 with the main body 111 (not shown) underneath. The mounting 196 surrounds the circular opening 188 . The holes 190 bored through a first pair of thick arms 196 A of the mounting 196 receive screws (not shown) which secure the D.C. motor 112 , seen in FIG. 2A, to the top side of the cover 134 . A second pair of thin arms 196 B helps balance the motor 112 on the cover 134 so that there is no wobble of the motor 112 during operation.
[0066] Also in FIG. 4C, there are illustrated portions of the four protuberances 168 and the channel 147 through which lubricant may be squirted.
[0067] A second dimple 152 A is provided to allow access, upon drilling therethrough, to the first central gear 118 , seen in FIG. 2A.
[0068] Also, in FIG. 4C, there is a bore 198 through which the opposite end 126 B of the central shaft 126 , shown in FIG. 2A, may be viewed and accessed, if necessary.
[0069] [0069]FIG. 5 is a partially cutaway cross-sectional view of the gear box 110 with the internal drive assembly removed therefrom. The mounting pad 196 , seen in a side elevational view, is formed integrally on the top side of the cover 134 .
[0070] In the partially cutaway view in the upper right corner of FIG. 5, there is seen a side elevational view of one of the welding rings 184 and one of the locating posts 154 projecting into a corresponding hollow holding tube 156 .
[0071] The cover 134 has a plurality of these locating posts 154 , of which only one is shown for the sake of simplicity, around a periphery of the cover 134 . Each locating post 154 extends into its corresponding hollow holding tube 156 which is formed integrally on the main body 111 and which corresponds in position to its post 154 so that the cover 134 is located securely on the main body 111 . Each post 154 is ultrasonically welded into its corresponding hollow holding tube 156 in order to increase the strength of the gear box 110 to resist high levels of torque and also to improve alignment of the cover 134 on the main body 111 .
[0072] Adjacent to the tube 156 , one of the acoustical chambers 180 is illustrated in phantom lines behind one of the thin rib walls 176 .
[0073] The channel 147 bored through the cover 134 into the bottom 145 of the second collar 146 allows the user to squirt lubricant into the gap 143 behind the output shaft 142 (not shown) which is surrounded at its midsection by the first collar 144 . Thus, the output shaft 142 , seen in FIG. 2A, is securely aligned as it is held at its midsection by the bore 144 B of the first collar 144 and at its nonworking end 142 B, seen in FIG. 2A, in the gap 143 at the bottom 145 of the second collar 146 .
[0074] Similarly, as also shown in FIG. 5, the blind hole 111 C in the first raised boss 111 A of the main body 111 receives the one end 126 A of the central shaft 126 , seen in FIG. 2A, while the flanged hole 134 C in the first raised boss 134 A of the cover 134 receives the opposite end 126 B, also shown in FIG. 2A, so that the central shaft 126 is secured at both ends 126 A, 126 B and is aligned between the first raised boss 111 A of the main body 111 and the first raised boss 134 A of the cover 134 when the cover 134 is ultrasonically welded to the main body 111 to form the gear box 110 .
[0075] Likewise, as also seen in FIG. 5, the flanged hole 111 D in the second raised boss 111 B of the main body 111 receives the one end 128 A of the second shaft 128 , seen in FIG. 2A, while the blind hole 134 D in the second raised boss 134 B of the cover 134 receives the opposite end 128 B so that the second shaft 128 is received at both ends 128 A, 128 B and is aligned securely between the second raised boss 111 B of the main body 111 and the second raised boss 134 B of the cover 134 when the cover 134 is ultrasonically welded to the main body 111 to form the gear box 110 .
[0076] Referring again to FIG. 5, the main body 111 and the cover 134 are secured to each other by ultrasonic welding to form the gear box 110 without screws. Although screws (not shown) are used to secure the D.C. motor 112 , seen in FIG. 2A, to the top side of the cover 134 , and the threaded bolts 162 , also seen in FIG. 2A, are used to secure the gear box 110 through the wall 104 to the slot machine 100 , these screws (not shown) and bolts 162 do not secure the cover 134 onto the main body 111 so as to form the gear box 110 .
[0077] The assembly of the invention is as follows, with initial reference to FIG. 2A. When the main body 111 is empty with the cover 134 off, the drive assembly is put into place in the following manner.
[0078] First, the output shaft 142 with the output gear 140 attached thereto is dropped into the bore 144 B of the first collar 144 . To prevent slippage of the output gear 140 along the output shaft 142 , the first collar 144 retains the output gear 140 on the output shaft 142 at one side. The pin 148 is then slipped through the working end 142 A of the output shaft 142 to prevent the output shaft 142 from falling out of the other side of the first collar 144 .
[0079] Next, the one end 126 A of the central shaft 126 is inserted into the first raised boss 111 A of the main body 111 . Then, the third gear 136 with the third pinion gear 138 is slipped onto the central shaft 126 until the third pinion gear 138 abuts against the first raised boss 111 A.
[0080] Subsequently, the one end 128 A of the second shaft 128 is inserted into the second raised boss 111 B of the main body 111 . Then, the second gear 122 with the second pinion gear 124 is slipped onto the second shaft 128 until the second pinion gear 124 abuts against the second raised boss 111 B.
[0081] The first central gear 118 with the first pinion gear 120 is then slipped over the central shaft 126 until the first pinion gear 120 abuts against the third gear 136 already on the central shaft 126 .
[0082] Now referring to the cover 134 , the small input gear 114 is slipped over and secured onto the input shaft 116 of the D.C. motor 112 which is next secured to the mounting 196 of the cover 134 by tightening screws (not shown) through the holes 190 seen in FIGS. 4A and 4C. As a result, the input gear 114 of FIG. 2A is extended through the circular opening 188 seen in FIGS. 4A and 4C.
[0083] As illustrated in FIG. 5, the cover 134 with the motor 112 (not shown) secured to the mounting 196 is then fitted onto the main body 111 by placing each locating post 154 into its corresponding hollow holding tube 156 .
[0084] Simultaneously, as shown in FIG. 4A, each welding ring 184 on the cover 134 will fit into the space between its corresponding welding pad 172 and short tube 174 shown in FIG. 3 B. Likewise, each locating rib 186 in FIG. 4A will snap into its corresponding acoustical chamber 180 in FIG. 3B.
[0085] With reference to FIG. 2A, when the cover 134 is secured by ultrasonic welding onto the main body 111 , the output gear 140 will be retained on the output shaft 142 between the first collar 144 of the main body 111 and the second collar 146 of the cover 134 . Thus, the first collar 144 retains the output gear 140 on one side while the second collar 146 retains the output gear 140 on an opposite side.
[0086] Because the D.C. motor 112 is secured onto the cover 134 instead of onto the main body 111 , the entire drive assembly inside the gear box 110 can be fully tested prior to sealing by ultrasonic welding of the cover 134 onto the main body 111 . In contrast thereto, in the prior art device shown in FIG. 1, the motor 12 is secured to the main body 11 so that the internal drive assembly cannot be tested until the cover 34 is sealed thereon to form the closed gear box 10 .
[0087] As best seen in FIG. 5, an assembler can ultrasonically weld the cover 134 to the main body 111 by causing each locating post 154 to melt in its corresponding hollow holding tube 156 . As the assembler runs an ultrasonic welding rod (not shown) around the outer periphery of the top side of the cover 134 seen in FIG. 4A, each welding ring 184 will likewise melt and fuse in the space between its corresponding pad 172 and its short tube 174 seen in FIG. 3B. Similarly, each locating rib 186 in FIG. 4A will be fused by the heat of the ultrasonic welding rod (not shown) along an inner edge of its corresponding acoustical chamber 180 in FIG. 3B.
[0088] The assembled gear box 110 shown in FIG. 2A is now ready to be secured to the drum or hopper 106 of the slot machine 100 . After the pin 148 is engaged into the drum or hopper 106 , the gear box 110 is secured to the slot machine 100 by screwing the threaded bolts 162 through an inner side of the wall 104 of the slot machine 100 into the raised protuberances 168 of the main body 111 .
[0089] The gear box 110 is now ready for operation. Initially, an operator programs the slot machine 100 to dispense a predetermined number of coins or tokens from the drum or hopper 106 after another predetermined number of coins or tokens are inserted into the slot machine 100 .
[0090] For example, after a player inserts 12 quarters into the slot machine 100 , an electrical signal is sent to energize the D.C. motor 112 . With reference to FIG. 2A, the motor 112 on the mounting 196 of the cover 134 turns the input shaft 116 so as to rotate the small plastic input gear 114 . The teeth 115 on the input gear 114 mesh with the teeth 117 on the first central gear 118 so as to turn the gear 118 and the first pinion gear 120 . The teeth 121 on the gear 120 mesh with the teeth on the larger second gear 122 and consequently turn the gear 122 and the second pinion gear 124 . The teeth 125 on the gear 124 mesh with the teeth 135 on the third gear 136 so that the third gear 136 and the third pinion gear 138 are rotated together.
[0091] Note that the third gear 136 and the third pinion gear 138 rotate independently of the first central gear 118 and the first pinion gear 120 , even though all four gears 118 , 120 , 136 and 138 are mounted on the same central shaft 126 . The teeth 139 on the gear 138 mesh with the teeth on the large output gear 140 so as to turn the gear 140 and the output shaft 142 secured through the center of the gear 140 .
[0092] At the working end 142 A of the output shaft 142 , the pin 148 turns the drum or hopper 106 filled with coins or tokens for a predetermined short period of time until about only ten coins or tokens fall out into a receiving tray (not shown) for the player to collect.
[0093] Occasionally, with the prior art device illustrated in FIG. 1, the drum or hopper 6 of the slot machine 1 would become stuck in an open position so that all of the coins or tokens therein would be dumped out and overflow the receiving tray for the player.
[0094] Such jackpots, although joyous for the players, are not profitable for the operators of the casinos and other licensed gambling institutions.
[0095] As the reader can realize, these jackpots were caused when the prior art gear box 10 failed and allowed the drum or hopper 6 of the slot machine 1 to remain open so that all of the coins or tokens were emptied out as winnings for the players.
[0096] With the present invention which is more reliable in operation than the prior art device of FIG. 1, such jackpots will be eliminated and only the predetermined number of coins or tokens will be dispensed after a higher predetermined number of coins or tokens are inserted into the slot machine 100 by each player.
[0097] Although the present invention has been described by way of a preferred embodiment, other modifications will be realized by those persons skilled in this particular technology after reading this disclosure. However, these modifications may be considered within the scope of the appended claims if such modifications do not depart from the spirit of this invention. | A high torque resistant and strong screwless plastic gear box has a reduced thickness at its output shaft. The gear box and a reduction drive assembly therein may be used particularly, but not exclusively, in a slot machine with a spinning drum or hopper which holds coins or tokens to be released therefrom. The gear box includes a main body and a cover which is ultrasonically welded thereto. Locating posts, holding tubes, inner welding pads, outer surrounding tubes, and locating ribs are provided to weld the cover to the main body. Acoustical chambers are formed between outer walls and inner arcuate walls of the main body. The inner arcuate walls surround all of the shafts and gears inside the main body. This double-walled construction reduces noise and provides surprising mechanical strength. All of the gears are mounted on only three shafts secured between the main body and the cover. Four of the gears are stacked on a single central shaft and rotate in two pairs independently of each other. | 8 |
RELATED APPLICATIONS
This application is a continuation of International Application No. PCT/DE2007/000361 (International Publication Number WO/2007/101423), having an International filing date of Feb. 27, 2007 entitled “Gasturbinenbauteil Sowie Verfahren Zur Bearbeitung Von Gasturbinenbauteilen Im Rahmen Der Herstellung Oder Instandsetzung Dieser Gasturbinenbauteile” (“Gas Turbine Component And Method For Machining Gas Turbine Components During Production Or Reconditioning Of Said Gas Turbine Components”). International Application No. PCT/DE/2007/000361 claimed priority benefits, in turn, from German Patent Application No. 10 2006 010 927.9, filed Mar. 9, 2006. International Application No. PCT/DE/2007/000361 and German Application No. 10 2006 010 927.9 are hereby incorporated by reference herein in their entireties.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[Not Applicable]
MICROFICHE/COPYRIGHT REFERENCE
[Not Applicable]
BACKGROUND OF THE INVENTION
The present technology relates to gas turbine components and a method for machining gas turbine components. More specifically, the present technology relates to systems and methods for machining of gas turbine components during production and repair or reconditioning of these gas turbine components.
Gas turbine components haveing an internal cavity—subsequently referred to as first inner cavity—are already known. An example of such a configuration is a blade, like a guide vane or turbine blade of a gas turbine or of an aircraft engine, which is provided with a first inner cavity for cooling purposes. Such a first inner cavity, which can also be designed as a channel, an arrangement of several cooperating channels, a chamber and/or a chamber system, can have one or more undercuts and can then be connected to holes or slits, so that the entire arrangement of inner cavity and holes or slits permits air flow through the blade. Such blades are also referred to as internally cooled or internally air-cooled blades.
In the production and repair of such blades, a number of machining steps is typically carried out. For example, it can be prescribed that one of the machining steps conducted in the context of production is “casting” in the blade, in which the first inner cavity is formed in the context of this casting process. The first inner cavity, however, can also be formed in a different way. Holes or cooling holes or slits or cooling slits are generally introduced after formation of the mentioned first cavity. This can be so that by means of a mechanical machining method, like drilling, cooling holes are introduced that extend from the outer surface of the blade to the first cavity. Another possibility is to introduce such holes or slits by means of a laser. While it can be relatively easily ensured that the limitation section of the first cavity opposite the hole being formed will not be adversely affected or damaged during the mechanical drilling of a cooling opening, it is much more difficult to ensure during laser drilling. During mechanical drilling, an adverse effect on the mentioned opposite wall section can be simply avoided by controlling the drilling depth, however, during laser drilling, there is a not insignificant hazard that the laser radiation will produce undesired changes on the opposite wall section of the cavity limitation.
The effect area, or the area upon which the laser drilling is intended to have a drilling effect, is not only in the area in which the laser drilling influences, as laser drilling also affects the wall section of the first cavity opposite the laser drilling. It is desirable, however, to avoid or reduce the adverse effects or changes that occur in the opposite wall section as a result of laser drilling.
This problem of having effects occur in areas of the component, or the gas turbine component in which effects are undesired during the production or repair of gas turbine components by machining steps or by a machining tool, however, does not only exist during the mentioned laser drilling.
This problem can also occur, for example, during coating of gas turbine components—be it in the context of the manufacturing process or in the process of repair. If, for example, an internally air-cooled blade is at least partially de-coated in the context of repair work and then re-coated, there is a hazard that during this coating, the cooling air holes will be clogged or their cross-sectional areas at least reduced.
Here again, during a machining step, namely coating, an effect occurs on an area of the component or blade in which the corresponding effect is undesired.
The underlying task of the presently described technology is to devise a method for machining especially internally cooled or internally air-cooled gas turbine components, where the machining occurs during production or repair of these gas turbine components, in which the hazard of undesired or damaging effects is reduced or even avoided during the machining steps on the gas turbine component.
BRIEF SUMMARY OF THE INVENTION
According to the presently described technology, various embodiments of methods are proposed for machining a gas turbine component or components. The present technology also describes various embodiments of gas turbine components.
According to the present technology, a method is proposed for machining gas turbine components during the production or repair (reconditioning) of these gas turbine components, particularly internally cooled or internally air-cooled gas turbine components. A component is provided having at least a first internal cavity and is initially prepared. Then at least one first machining step is conducted on this component. To limit the area on which an effect occurs in the first machining step, before performing the at least first machining step, plastic material is introduced to the first cavity. This plastic material is removed again after the machining steps or the first machining step from the first cavity. As stated, a method for machining of gas turbine components is proposed; in this context, the gas turbine component being machined may be a finished gas turbine component or a partially finished or repaired gas turbine component. In certain embodiments, the gas turbine component is a gas turbine blade.
In certain embodiments, the gas turbine component is an internally cooled or internally air-cooled gas turbine blade. The gas turbine blade can be configured as a guide vane or blade of a turbine or of a compressor of an aircraft engine.
In certain embodiments, the plastic material is injected or applied in the liquid or viscous state. In certain embodiments, the plastic material is injected into the component, or alternatively, the first cavity can be sprayed with the plastic material.
The first cavity can be an opening or an opening extending into the interior of the gas turbine component, a channel or several cooperating channels in an arrangement, a chamber or a chamber system or be formed from them. In certain embodiments, the first cavity can also be a hole, in particularly a laser hole or a cooling (air) hole. In certain advantageous embodiments, it is proposed that the first cavity forms a type of channel, from which, in the finished state of the gas turbine blade, laser holes or cooling holes extend to the outer surface of these gas turbine blades. Such a first cavity, designed as a channel, can extend lengthwise; it can be curved or meander or run in some other way. The first cavity can have one or more undercuts. In an advantageous embodiment, the first cavity is produced in the context of a casting process.
The first cavity or first channel, in certain advantageous embodiments, has on its end an opening that is opened outward or main opening and is essentially closed on its other end.
Certain embodiments propose that the machining step or first machining step be conducted by means of a laser. This first machining step can be laser drilling. Through holes or cooling holes are introduced to the gas turbine component or blade with such laser drilling. Such cooling holes can be introduced, so that they connect the mentioned first cavity or first channel to the outside surface of the blade.
The mentioned plastic material can therefore be introduced into the first cavity or channel beforehand. The plastic material can be positioned in the first cavity along an imaginary extension of the generated laser holes or cooling holes, such that the plastic shields the opposite wall section of the channel or first cavity.
The plastic material, in a certain embodiments, is a plastic material that can be removed essentially free of residue. In certain advantageous embodiments the plastic material is polystyrene.
In a modification of the method according to the present technology, in which the already mentioned cooling holes are produced by laser drilling, it can be proposed that after laser drilling, the blade foot is tightened in a holding device with good heat conductivity or in copper jaws. This holding device or these copper jaws can be configured, for example, so that they have an oxygen or compressed air feed. The blade can then be configured, so that the first channel or the first cavity in the area of the blade foot is formed open outward or forms a main opening, in which the oxygen or compressed air feed is connected, so that oxygen or compressed air can be introduced, and specifically in order to carry out quality control, for example, in combination with a flow measurement or the like. A measurement device can be provided for such quality control in the context of which it is checked, in particular, whether laser or cooling openings are dimensioned in the desired manner.
It can be proposed, for elimination or removal of the plastic material or polystyrene from the component, that an induction coil or induction mat be placed around the component or blade, and that the coil heats the blade, the cavity or the blade channels. In certain embodiments, the blade, the cavity or the blade channels are flooded with oxygen or atmospheric oxygen at the same time as the heating. Heating can occur at a temperature in the range between 400° C. and 800° C., preferably in the range from 400° C. to 600° C., and especially at about 500° C. The aforementioned temperature values are particularly suitable, if the plastic material is polystyrene. Polystyrene then burns up or evaporates essentially free of residue.
It can also be prescribed that the blade then be cooled or rapidly cooled. This rapid cooling can occur via the copper jaws or the holding device, whose material preferably has good heat conductivity. Rapid cooling can occur, for example, with additional air or additional water, and specifically air or water that is guided to the copper jaws or holding device, whose material preferably has good heat conductivity. This can permit the blades to then be cooled relatively quickly, so that they can be grasped by hand, so that the process times in the production process for gas turbine blades can be reduced.
In certain embodiments, before filling of the first cavity with the plastic material, one or some holes or openings are introduced, so that they connect the outer surface of the blade to the mentioned cavity. Such holes or openings can be arranged, for example, on the end of the cavity facing away from the mentioned main opening. The introduced holes or openings, which can be generated by laser drilling, can help ensure that a closed, or essentially closed air-filled space is not formed, which can create an air cushion thereby preventing penetration of plastic into the corresponding section. Thus, during the filling of the component with plastic, the air can therefore escape through the aforementioned holes or openings.
It should be mentioned that the terms “first” and “second” machining step were chosen, in particular, to identify or for distinguish the machining steps, in which, in an advantageous embodiment, the second machining step occurs after the first machining step, if preferred modifications have both of these machining steps. However, before the first or between the first and the second machining step, one or more additional machining steps can also be conducted.
The gas turbine component or the blade is preferably made from a metallic or metal-containing material and/or from material containing cobalt and/or nickel (especially as base material or as matrix material) and is optionally coated or provided with a coating and/or alitized. Other materials, and especially materials that are used in the current state of the art for gas turbine components, particularly gas turbine blades, can be used as material for the gas turbine component or blade.
To perform the method or for machining, especially in the context of production or repair of the gas turbine component or components, particularly blades, a device can be used that is configured as follows, in combined or integrated form, and for which the applicant reserves protection: a laser; a holding device to hold the gas turbine component, which is configured in the aforementioned manner; an injection device to inject the plastic material, particularly for the injection of polystyrene; and a heating device to eliminate or remove the plastic material, configured, in particular, as an induction coil or induction mat or a device having such a coil or mat. In certain embodiments, the device can potentially having one or more of the following optional devices: an electronic control device to control the process for machining of the gas turbine component; a device for de-coating of the gas turbine component, which can be a laser; and a measurement device to measure or check the machining results produced by the method or to measure one or more characteristics of the gas turbine component. It can also be prescribed that an oxygen or compressed air feed device be provided, which is optionally combined in the aforementioned manner with the holding device.
Without limiting the present technology thereto, practical examples of the present technology will be further explained with reference to figures, which are identified below.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 depicts a gas turbine blade in accordance with an embodiment of the present technology.
FIG. 2 depicts a flow profile schematic diagram of the blade depicted in FIG. 1 .
The components, systems and methods of present technology will be explained in accordance with the figures.
DETAILED DESCRIPTION OF THE INVENTION
A blade 1 of a gas turbine or aircraft engine is shown in FIGS. 1 and 2 . This blade 1 is configured as a turbine blade. In other embodiments of the present technology, to which the following description can also apply, such a blade can also be configured as a guide vane of a gas turbine or aircraft engine or as a guide vane or blade of a compressor of a gas turbine or aircraft engine.
The blade 1 has a blade body 10 and a blade foot 12 . The blade 1 also has a first inner cavity 14 or a first inner chamber or a first inner channel 14 , whose wall or limitation is bounded in FIGS. 1 and 2 by the (dashed) lines 14 a . This first inner cavity 14 can be provided with undercuts or have undercuts. The first inner cavity 14 discharges outward in the area of blade foot 12 . The corresponding (main) opening 20 provided there in the region of the blade foot 12 is positioned, so that, in a blade 1 mounted in an aircraft engine, it is situated radially inward or in the radially inward arranged area of blade 1 , referred to the turbine axis of rotation. According to a gas turbine part according to the present technology, which is a blade 1 , in particular, it is prescribed that the first inner channel 14 or first cavity 14 be filled with a plastic material that can be removed free of residue, which, in certain embodiments can be polystyrene. This can be such that the first cavity 14 is filled essentially fully with the mentioned polystyrene.
The blade 1 depicted in FIGS. 1 and 2 also has a number of first openings 16 , as well as a number of second openings 18 . The openings 16 , 18 extend from the outer surface 21 of blade 1 to the first inner cavity 14 , and specifically in the area of blade body 10 . The first openings 16 are configured here as holes, and specifically laser holes, and can also be referred to as cooling holes. The second openings 18 are configured here slit-like, but, as an alternative, can also be (laser) holes or the like.
The first inner cavity 14 is connected to the blade exterior via a main opening 20 of the first inner cavity 14 , which, as already mentioned, is arranged here in the area of blade foot 12 . The first inner cavity 14 is therefore connected to the exterior of the blade 1 only via the main opening 12 , as well as (with respect to its cross section) relatively smaller openings 16 , 18 arranged in the area of the blade body. The channel arrangement or cavity arrangement formed in this case serves for cooling or air-cooling. The blade 1 can receive relatively cold air into blade 1 in relation to the ambient temperature via the main opening 20 , which then emerges via openings 16 , 18 . The “relatively” cold air can lie in the range of 700° C., which is relatively low in comparison with the temperatures that are produced by the combustion gases of an aircraft engine in the area connected to the combustion chamber.
It should be noted that the mentioned polystyrene is shown symbolically in cutouts by the cross-hatched areas 22 .
A method in accordance with the present technology can occur as follows in a practical example.
A blade 1 provided with a first inner cavity 14 is initially produced. The blade 1 can be configured as shown in FIGS. 1 and 2 or explained with reference to these figures, in which, however, the openings 16 , 18 are initially not present.
Second openings 18 , which connect the outside of blade 1 to the first inner cavity 14 , as is readily apparent in FIG. 2 , where the flow profile or a section through the blade body 10 is shown, are then produced, for example, by means of a laser. The openings 18 can be positioned, as shown in FIGS. 1 and 2 , in the area of the trailing edge 24 of blade 1 , and specifically on the pressure side 26 there. As mentioned, the openings 18 can also have a shape different from that prescribed here.
Polystyrene 22 is then injected into hollow chamber 14 or the hollow chamber 14 is sprayed with polystyrene 22 , which can occur through the second openings 18 and/or the main opening 20 . Depending on whether it occurs via the main opening 20 or the second openings 18 , it is ensured by the other openings 20 and 18 that no compressed air cushion builds up, which might prevent complete filing of the chamber 14 with polystyrene 22 .
The first holes or cooling holes 16 are now produced by means of a laser. The holes 16 can therefore also be referred to as laser holes. These cooling holes 16 are arranged in the configuration according to FIGS. 1 and 2 in the area of the leading edge 28 of blade 1 . The adverse and/or undesired effects of laser radiation on the wall section of the component, particularly the wall 14 a bordering the first cavity 14 and opposite the forming holes 16 , is prevented during laser drilling as a result of the first inner cavity 14 being filled with polystyrene 22 or a plastic material. This is schematically shown in FIG. 2 for one of the holes 16 , in which a laser head is denoted with reference number 30 , laser radiation is denoted with reference number 32 and an opposite wall section is denoted with reference number 34 . As shown, the opposite wall section 34 is shielded by the polystyrene 22 , therefore preventing an undesired effect of the laser radiation 2 on the opposite wall section 34 , or a change, especially a permanent change, in the surface or material properties of this wall section 34 .
In certain embodiments, the laser radiation 32 , or its intensity, may be adjusted or set, so that, the polystyrene 22 , sufficiently prevents the laser radiation 32 from having an effect on the (opposite) wall section 34 during laser drilling. It can then be stipulated that the act of laser radiation 32 can have an effect may evaporate, or partially evaporate the polystyrene 22 .
When the laser has formed the holes 16 in the aforementioned manner, the polystyrene 22 is then removed again. This can occur by heating the polystyrene 22 and burning it or evaporating it. The corresponding heating of the polystyrene 22 can occur, for example, as schematically shown in FIG. 1 , by means of an induction coil 36 . In certain embodiments, copper jaws 38 are provided, in which the blade foot 12 can b e tightened. Such copper jaws 38 , as schematically shown in FIG. 1 , can have an oxygen or air feed or feed device 40 , which can be connected to the main opening 20 . It should be mentioned that, instead of the induction coil 36 , an induction mat or another appropriate heating device can be provided. The coil 36 or mat is placed around the blade body and optionally the blade foot 12 . The heating device or induction coil 36 heats the blade channels or their interior to 500° C. while the blade channels or their interior are flooded with oxygen or atmospheric oxygen via the oxygen or air pressure feed device 40 . The polystyrene burns or evaporates essentially free of residue. Only water (H 2 O), as well as carbon dioxide (CO 2 ) are then formed. It can also be prescribed that rapid additional cooling can occur with air or water via the copper jaws 38 .
In certain embodiments, after removal of the polystyrene 22 , the polystyrene 22 is injected again, such that that the openings 16 , 18 are injected with the polystyrene 22 in addition to, or alternatively from the first cavity 14 . In certain embodiments, a subsequent coating process, which can also be referred to as a second machining step, is performed, making it possible to coat the surface of blade 1 with a coating material, without the coating material penetrating into openings 16 , 18 , thereby changing their cross-sectional surface or even clogging them in the area of these openings 16 , 18 . After the corresponding coating process, through which a hot temperature-resistant layer of a corrosion-temperature-resistant layer or the like can be applied, the polystyrene 22 can be removed again in the aforementioned manner. It should be mentioned that the previously discussed second introduction of polystyrene 22 can occur via openings 16 and/or 18 and/or the main opening 20 . It should also be noted that elimination or removal of the polystyrene 22 occurs in the practical example just described by heating, and specifically inductively. In certain embodiments, however, other removal methods can also be provided, for example, chemical removal methods.
As shown in the practical example, this permits the area of effect of tools or the area of effect that is present in the context of machining steps to be limited in simple fashion by use of polystyrene 22 or a corresponding plastic. It should be mentioned that the injection molding of polystyrene can be carried out quickly, cleanly and cost-effectively. Burning or evaporation of polystyrene is also free of residue, rapid, cost-effective and environmentally safe.
The present technology has now been described in such full, clear, concise and exact terms as to enable a person familiar in the art to which it pertains, to practice the same. It is to be understood that the foregoing describes preferred embodiments and examples of the present technology and that modifications may be made therein without departing from the spirit or scope of the present technology as set forth in the claims. Moreover, while particular elements, embodiments and applications of the present technology have been shown and described, it will be understood, of course, that the present technology is not limited thereto since modifications can be made by those familiar in the art without departing from the scope of the present disclosure, particularly in light of the foregoing teachings and appended claims. Moreover, it is also understood that the embodiments shown in the drawings, if any, and as described above are merely for illustrative purposes and not intended to limit the scope of the present technology, which is defined by the following claims as interpreted according to the principles of patent law, including the Doctrine of Equivalents. Further, all references cited herein are incorporated in their entirety. | The present technology relates to the problem that during diverse machining steps of application to the production or reconditioning of internally cooled gas turbine blades, an undesired effect may be had on sections of the gas turbine blades and proposes, as an improvement, to inject the cavity of the gas turbine blades before the machining steps with a plastic material which can be removed without trace, such as polystyrene, which can be subsequently removed again, in particular by heat. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention This invention relates to lock mechanisms for holding target wafers to articles of merchandise and more particularly it concerns a novel lock construction which can be manufactured easily and economically and which provides strong and reliable locking with positive release.
2. Description on the Prior Art
U.S. Pat. No. 4,590,461 shows a lock mechanism for holding a target wafer to an article of merchandise. The target wafer is a thin flat plastic housing in which an electrical circuit is embedded. The electrical circuit is designed to produce a characteristic disturbance to an electromagnetic interrogation signal when the article of merchandise is carried past a doorway or other exit path where the interrogation signal is generated. This disturbance is detected by a monitor at the doorway and the monitor in turn actuates an audio or visual alarm. The lock mechanism is releasable by means of a special magnetic tool under the control of a sales clerk or other authorized person; and upon release of the lock mechanism, the target wafer is removed from the merchandise so that the merchandise can be carried out through the doorway without actuating the alarm. The lock mechanism shown in U.S. Pat. No. 4,590,461 is known as a "ball clutch" type lock mechanism. This mechanism comprises a cone and an internally tapered ring arranged within the wafer housing and a spring which presses the cone into the tapered ring. The cone has an axial hole to accommodate the shank of a pin fastener and a pair of transverse holes which intersect the axial hole and which accommodate locking balls. When a fastener pin is projected into the axial hole it passes between the balls. The cone holds the balls in position between the pin shank and the tapered wall of the ring. Any axial force on the pin in the direction of pin removal causes the balls to become more tightly squeezed between the pin and the ring wall. The lock is released by application of a magnetic force to the cone to pull it against the force of the spring in a direction opposite the direction of pin removal. This cone movement brings the balls to a position along the ring wall where they are no longer wedged between the pin and wall; and the pin may then be easily removed.
The above described lock mechanism is very strong and secure and it operates very reliably to release the pin when a magnetic force is applied to the cone. The mechanism however is somewhat expensive to manufacture in that the cone and ring must be individually machined and a separate spring and balls must also be provided.
U.S. Pat. No. 4,722,119 describes another lock mechanism which comprises a one piece sheet metal element which is slit to form flange-like jaws that bend up and away from each other when the shank of a pin type fastener is pushed between them. Any axial force on the fastener in the direction of removal forces the flange jaws more tightly against the pin shank. However, when a magnetic force is applied to risers extending from the flange jaws, this force, according to the patent, pulls the jaws in a direction away from pin removal and forces them apart from each other and from the pin shank so that the pin may be removed.
The above described lock mechanism of U.S. Pat. No. 4,722,119 is of one piece construction; however, since the flanges which lock the pin must be flexed to release the pin, the device is either too rigid to permit reliable release or it is too flexible to provide secure locking.
SUMMARY OF THE INVENTION
The present invention overcomes the above described problems of the prior art. According to the present invention there is provided a novel target wafer lock mechanism which is economical to produce and which is strong and durable while permitting positive and reliable release when a magnetic field is applied to the mechanism.
In one aspect, the present invention comprises a housing formed with an internal cavity and a pin access hole extending along a longitudinal axis into the cavity from outside the housing. A rigid catch element is mounted within the cavity for limited pivotal movement about a pivot axis perpendicular to and displaced from the longitudinal axis. The catch element includes a front edge which moves toward and away from the longitudinal axis as the catch element pivots about the pivot axis. An elongated magnetizable actuation element is arranged within the cavity to extend from a location on the catch element displaced toward the longitudinal axis from the pivot axis. The actuation element extends generally along the longitudinal axis in a direction away from the access hole.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an article of merchandise to which is attached a target wafer having a lock mechanism according to one embodiment of the invention;
FIG. 2 is an enlarged fragmentary section view taken along line 2--2 of FIG. 1;
FIG. 3 is a plan view taken along line 3--3 of FIG. 2;
FIG. 4 is a section view taken along line 4--4 of FIG. 3 showing the insertion of a fastening pin into the lock mechanism;
FIGS. 5, 6, and 7 are views similar to FIG. 4 but showing the locking mechanism with the fastening pin fully inserted, showing the lock mechanism released upon application of a magnetic field and showing the fastener pin being removed during application of a magnetic field;
FIG. 8 is an exploded perspective view of the target wafer and lock mechanism of FIG. 1; and
FIG. 9 is an exploded perspective view, partially in section of a spring and catch subassembly portion of the lock mechanism of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIG. 1, an article of merchandise to be protected from theft, such as a shirt 10, is provided with a target wafer 12 which is fastened to the shirt with a lock mechanism 14 according to the present invention. As is well known in the electronic article surveillance industry, the target wafer 12 contains an electronic element or circuit which is capable of causing a characteristic disturbance to an interrogating electromagnetic field being generated at a doorway or egress passageway from a protected area. If the shirt 10 with the wafer 12 attached is carried through the doorway or other egress passageway, the element or circuit in the wafer will cause the characteristic disturbance and a monitor at the doorway or passageway will detect this disturbance and actuate an alarm. When the shirt 10 is purchased, the clerk or other authorized person uses a special tool (not shown) to apply a strong magnetic field to the lock mechanism 14 which enables the wafer 12 to be removed from the shirt so that the shirt can be taken through the doorway or egress passageway without actuating the alarm.
The construction of the wafer 12 and the lock mechanism are best seen in FIGS. 2 and 3. As shown in FIG. 2, the wafer 14 comprises a flat expansive cover 16 and base 18, both of which are molded from high impact polystyrene. The base 18 is formed with a peripheral wall 20 which defines a target circuit recess 22. The recess is also formed with abutments 24 and shoulders 26 which support a target circuit 28. The target circuit per se is not part of the invention and any type of target or target circuit may be used. However, for purposes of illustration, there is shown a target circuit suitable for producing characteristic disturbances to signals at microwave frequencies. This target circuit comprises an antenna 30 (FIG. 3) made of sheet copper in a generally U-shaped configuration with a first longer leg 32 and a second shorter leg 34. A diode 36 is connected across the legs 32 and 34 of the antenna 30 and is attached thereto at weld points 38. The longer antenna leg 32 extends beyond the weld point 38 to the opposite end of the target where it curves part way around the end of the target housing and then terminates. The shorter antenna leg 34 turns sharply inward just beyond the weld point 38 and extends toward the longer leg where it terminates just short of the longer leg.
The base 18 is formed near one end with a lock housing projection 40 (FIG. 2) of generally conical outer configuration which projects outwardly from the surface of the base. The lock housing projection is formed with a lock housing cavity 42 which opens out inside the peripheral wall 20 of the base 18. An abutment wall 44 extends up out of the base 18 around the cavity 42.
The cover 16 is formed with a dome shaped fastener support region 46 in alignment with the lock housing projection 40 on the base 18. A recess 48 is formed in the fastener support region to accommodate the upper end of the abutment wall 44 to form a solid enclosure for the lock mechanism to be described. A fastener pin access opening 50 extends through the center of the dome shaped fastener support region 46 in the cover 16 and into the lock housing cavity 42 of the base 18. The fastener pin access opening 50 extends along a longitudinal axis A which also forms the longitudinal axis of the lock housing cavity 42.
A lock mechanism is provided inside the lock housing cavity 42. This lock mechanism comprises a tubularly shaped spring unit 52 of rectangular cross-section, which fits closely within the cavity 42 and rests on a ledge 54 formed within the cavity, and a pair of catches 56 (FIG. 3) which are supported by the spring unit. The catches 56 each have a wing portion 58, which rests on the spring unit 52, and a leg portion 60 which extends down through the spring unit toward the bottom of the lock housing cavity 42.
A fastener pin 62 (FIG. 2), having an expansive head 64 and a cylindrical shank 66, pins the shirt 10 or other merchandise to be protected to the target wafer 12. The pin shank 66, which is formed with axially spaced peripheral recesses 68 and a tapered point 70, passes through the shirt 10 and then it extends through the access opening 50 and into the lock housing cavity 42 where it is gripped by the catches 56 of the lock mechanism. Any attempt to remove the pin 62 forcibly will only cause the catches 56 to grip the pin shank 66 more tightly. However when a strong axial magnetic force is applied to the catch legs 60, the catches 56 are tilted to release the pin shank 66 and the pin 62 is easily removed. The peripheral recesses 68 along the pin shank are not necessary to the invention but merely provide a better gripping surface for the catches 56.
The construction of the spring unit 52 and the catches 56 is best seen in FIGS. 8 and 9. As there shown, the spring unit 52, which is molded in one piece from a strong yet flexible material such as Delrin 500, is of square cross-section tubular configuration. The spring unit 54 comprises a pair of end walls 72, each having a center post 74 extending upwardly from near the center of its upper edge, and a pair of side walls 76, each having a spring arm 78 extending in cantilever fashion inwardly and upwardly from a central location between its upper and lower edge. The outer cross-section of the spring unit 52 is dimensioned to fit closely within the lock housing cavity 42 formed in the lock housing projection 40 of the wafer base 18.
The size of the lock mechanism components is not critical to the invention; however, to illustrate the relative sizes of these components the following dimensions of the preferred embodiment are given. In this embodiment the end walls 72 are 0.372 inches long, 0.062 inches thick and slant downwardly from a height of 0.120 inches where they meet the side walls 76 to the center posts 74. The center posts 74 rise to a height of 0.172 inches from the lower edge of the end walls and have a width at their upper edge of about 0.050 inches. As shown, the center posts curve outwardly near the bottom thereof where they merge with the downwardly slanting end walls 72. The center posts 74 are mutually offset such that one of the posts is closer to one of the side walls 76 and the other center post is closer to the other side wall. The amount of the offset is about 0.025 inches. The side walls 76 are each 0.344 inches long, 0.120 inches high and 0.030 inches thick. The spring arms 78 are each 0.110 inches long, approximately 0.020 inches thick and 0.082 inches wide. The spring arms are molded integrally to the side walls and are each formed with a cylindrical recess having a radius of 0.010 inches along the underside thereof to provide a hinge of about 0.015 inches thickness where they join the side walls 76. The hinges provide a predetermined amount of resilience which is sufficient to support the catches 56 and yet permits the catches to bend the arms downwardly in response to an applied magnetic unlocking field. The spring arms 78 extend from locations on the inner surface of the side walls 76 midway along their length and about 0.040 inches from their upper edge. The spring arms slant upwardly as they extend from the side walls so that their outer ends are about 0.020 inches below the upper edges of the side walls 76.
The catches 56 are each formed from a ferromagnetic material of sufficient hardness to hold the shank 66 of the fastener pin 62 securely without appreciable wear. Preferably the catches 56 are formed of SAE 1010 cold rolled steel which is heat treated to form a carbon nitride casing and then nickel plated. In the illustrated embodiment, the catches 56 are 0.036 inches thick. The wing portions 58 are flat, generally rectangular sections about 0.344 inches long by 0.136 inches wide with a rear edge 82 and a front edge 84. A gripper projection 86 extends out from the center of the front edge 84 to a distance of about 0.188 inches from the rear edge 82. The front of the gripper projection 86 contains an elliptical recess 88 which forms a gripper surface to grip the shank 66 of the fastener pin 62. In the illustrated embodiment, the elliptical recess has a major axis, parallel to the front edge 84, of 0.048 inches and a minor axis, perpendicular to the front edge 84, of 0.036 inches. The major axis of the elliptical recess 88 lies along the front edge of the gripper projection 86 so that the recess 88 extends into the gripper projection by 0.036. The minor axis of the recess 88 is midway along the length of the catch wing portion 58. The catch leg portion 60 extends out from the front edge 84 of the wing portion 58 on one side of the elliptical recess 88 and is bent to extend downwardly therefrom at an angle of about 65 degrees from the plane of the wing portion 58.
In assembling the target wafer 12, as shown in FIG. 8, the antenna 30, with the diode 36 welded thereto (or other field disturbance element or circuit) is placed in the base 18. Also, the spring unit 52 is positioned in the lock housing recess 42 and the two catches 56 are positioned over the spring unit. As can be seen, the wing portion 58 of each catch rests, respectively, on an associated side wall 76 and spring arm 78 of the spring unit 52. Also, the leg portion 60 of each catch extends down through the spring unit and into the lock housing recess 42. Because the leg portions 60 of the catches are offset with respect to the gripper edge 88, when the catches are assembled facing each other, their respective leg portions extend down through the spring unit 52 and the lock housing recess 48 along opposite sides of their common longitudinal axis. When the spring unit 54 and catches 56 are in place, the cover 16 is positioned over the base 18 and is sealed to the base either with an adhesive or by some other well known technique such as ultrasonic welding.
FIGS. 4-7 illustrate the use of the above described lock mechanism. As shown in FIG. 4, the shank 66 of the fastener pin 62 is pushed through the shirt 10 (or other merchandise to be protected) and then through the fastener pin access opening 50 in the dome shaped fastener support region 46 of the wafer cover 16. The pin 62 is pushed into the opening 50 until the expansive head 64 of the pin presses the material of the shirt 10 down against the fastener support region 46 as shown in FIG. 5.
As shown in FIG. 4, before the pin 62 is pushed into the wafer 12, the catches 56 are loosely held in the lock housing recess 48 above the spring unit 52 and below the dome shaped fastener support region 46 of the cover 16. The rear edge 82 of each catch wing portion 58 rests on the upper edge of a different sidewall 76 of the spring unit near the lock housing abutment wall 44. The wing portions 58 of the catches 56 each extend from their respective spring unit sidewalls 76 toward the longitudinal axis A where their respective gripper projections 86 meet, as shown in FIG. 3. As can be seen in FIG. 3, the recesses 88 formed in the two catches 56 cooperate to form a small opening 92 along the axis A.
The spring arms 78 of the spring unit 52 support the catches 56 near the front edges 84 of their wing portions 58 to hold the wing portions in a position such that they slant downwardly away from the access opening as shown in FIG. 4. However, because of the flexibility of the spring arms, the wing portions 58 can pivot to slant further downwardly about swing axes S (FIG. 3) extending perpendicular to and displaced away from the longitudinal axis A, i.e. along the upper edges of the sidewalls 76, when a force is applied to the catches 56 in a direction along the longitudinal axis A and away from the access opening 50.
When the catches 56 are held in their normal position by the spring arms 78, the axes of their elliptical gripper recesses intersect the longitudinal axis A. Thus when the shank 66 of the fastener pin 62 is pushed through the access opening 50, the tapered point 70 of the pin passes through the opening 92 formed by these two recesses. The pin shank 66, however, is larger than the opening 92 (FIG. 3) and the force of the pin 62 overcomes the force of the spring arms 78 and causes the catch wings 58 to swing about their respective swing axes S. As a result, as shown in FIG. 5, the gripper projections 86 of the gripper wings 58 move away from each other and the size of the opening 92 becomes enlarged to accommodate the pin shank 66.
While the pin shank 66 moves downwardly between the catch wings 58, the spring arms 78 maintain the front edges of the wings pressing against the shank. After the pin shank is fully inserted, as shown in FIG. 5, any upward axial force on the pin tending to pull it out of the fastener will simply cause the catch wings 58 to pivot upwardly about their respective swing axes S so that their front edges press even more tightly against the pin.
The upward force transmitted from the pin shank 66 to the catch wings will also tend to force the wings 58 away from each other. However, this movement is limited by the inner wall of the recess 42 against which the rear edges 82 of the wings come into contact. Because the cross section of the recess 42 in this region is rectangular (to accommodate the rectangular cross section of the spring unit 52), the unit pressure of the metal wing portions 58 against the plastic inner wall of the recess 42 is minimized. Consequently any axial force tending to pull the pin shank 66 upwardly will be strongly resisted by the thick wall surrounding the recess 42.
In order to release the pin 62 from the locking mechanism, an axial magnetic field is applied in the region of the lock housing projection 40 as shown in FIGS. 6 and 7. This magnetic field can be generated by any of several well known decoupling devices used with the well known ball clutch type fasteners. The magnetic field can be generated either by a permanent magnet or by an electromagnet as shown, for example, in U.S. Pat. No. 3,911,534. Such decoupler is represented schematically at 94 in FIGS. 6 and 7; and it applies a downward force along the axis A inside the lock housing 40. This magnetic force acts on the catch legs 60 and pulls them downwardly, thus causing the catches 56 to pivot about their respective swing axes S. The magnetic force is sufficient to overcome the upward pressure of the spring arms 78 on the underside of the catch wings 58 so that they swing down against the spring arms. This brings the front edges 84 of the catch wings away from each other and enlarges the opening 92 (FIG. 3) formed between the catches. The gripping force on the pin shank is thus released; and as long as the axial magnetic field remains applied, the pin can be withdrawn as shown in FIG. 7. It will be appreciated from the foregoing that the lock mechanism of the present invention is simple in structure, does not require high precision complex parts and assembly, and yet is reliable and durable in use. | A magnetically releasable pin lock which comprises catch elements mounted to pivot about axes perpendicular to and displaced from the pin axis and elongated magnetizable actuation elements which extend from the catch elements along the pin axis to be acted upon by applied magnetic decoupling fields and to move in response to such fields to pivot the catch elements and release the pin. | 4 |
TECHNICAL FIELD
The present invention is directed to the separation of air into a high purity oxygen product stream and a high purity nitrogen product stream.
BACKGROUND OF THE PRIOR ART
Various processes have been known and utilized in the prior art for the separation of air into its nitrogen and oxygen dominant constituents. Additionally, the use of a single pressure distillation column is known to have been used in the prior art for such separations.
U.S. Pat. No. 2,627,731 discloses a process for the rectification of air into oxygen and nitrogen, wherein a two sectioned or single distillation column are used alternatively. Air is cooled by heat exchange and introduced directly into the distillation column. A nitrogen product is removed from the overhead of the column and a portion is compressed in two stages. The first stage nitrogen compressed stream is recycled in order to reboil and condense a portion of the midpoint of the column by indirect heat exchange before being introduced into the overhead of the column as reflux. A second stage compressed nitrogen stream is recycled and partially expanded to provide refrigeration. This expanded stream is recycled to the nitrogen product line. The remaining stream of the second stage compressed nitrogen stream reboils the bottom of the column before being combined with the first stage compressed nitrogen stream and introduced into the overhead of the column as reflux.
U.S. Pat. No. 2,982,108 discloses an oxygen producing air separation system wherein a portion of the nitrogen generated from the distillation column is compressed and reboils the base of a high pressure section of the column before being introduced as reflux to the low pressure section of the column. The feed air stream is supplied in separate substreams into the high pressure section of the column and in an expanded form into the low pressure section of the column.
U.S. Pat. No. 3,210,951 discloses a fractionation cycle employing first and second fractionating zones operating under different pressures and including two reboiler/condensers. Both of the reboiler/condensers are interconnected with the stages of fractionation in such a manner as to effect the required reboil and reflux production with minimum pressure differential between the stages of rectification and also decreased the irreversibility of the overall fractionation process thereby obtaining the desired separation with the high pressure stage operating under substantially reduced pressure.
U.S. Pat. No. 3,214,926 discloses a method for producing liquid oxygen or liquid nitrogen. However, in the patent it is necessary to have two distillation columns, one at high pressure and another at low pressure in order to extract liquid oxygen.
U.S. Pat. No. 3,217,502 discloses a system which utilizes a single pressure distillation column. The product of this air separation system is gaseous and liquid nitrogen. Impure oxygen which is separated out in this system is vented to waste. In this patent, it is the oxygen waste stream which is expanded in order to provide refrigeration for the air separation system.
U.S. Pat. No. 3,277,655 discloses an improvement to the fractionation process taught in U.S. Pat. No. 3,210,951. In this process, the heat exchange occurring in one of the two reboiler/condensers between the bottoms liquid from the lower pressure column and the gaseous material from the high pressure column results in complete vaporization of the liquid from the low pressure column thereby satisfying the reboiler requirements of the low pressure column. Additionally, when the liquefied gaseous material from the high pressure column is introduced into the lower pressure column it improves the reflux ratio in the upper portion of the low pressure column which increases the separation efficiency and makes it possible to lower the pressure of the gaseous mixture entering the cycle.
U.S. Pat. No. 3,327,489 discloses another improvement to U.S. Pat. NO. 3,210,951 to lowr the pressure in the high pressure fractionator. In the process, the pressure reduction is obtained along with the associated power reduction by establishing a heat exchange between gaseous material, which may comprise the feed mixture, and a liquid component collecting in the bottom of the low pressure fractionator, with the liquid component being under different pressure.
U.S. Pat. No. 3,492,828 discloses a process for the production of oxygen and nitrogen from air wherein a nitrogen recycle stream is compressed and condensed in a reboiler in the base of a distillation column before being reintroduced into the column as reflux. A portion of the nitrogen recycle stream may be expanded in which the power provided by the expansion drives the compressor for the main nitrogen recycle stream.
U.S. Pat. No. 3,731,495 discloses an air separation system using an air feed compressor which is powered by combustion gases directed through a turbine. The turbine exhaust heats boiler steam to supplement the compressor drive. Electric generation is also considered. In addition, this reference utilizes two separate columns at separate pressures for the recovery of the individual gaseous components of air which are separated.
U.S. Pat. No. 3,735,599 discloses a control system for an air separation apparatus which comprises a reversing heat exchanger, an air liquefier, a single column rectifier provided with a condenser-evaporator and a cold generation device. In the apparatus, air is cooled in the reversing heat exchanger and liquefied in the air liquefier, the liquefied air is rectified in the single column to separate into liquid air abundantly containing oxygen and highly pure nitrogen.
U.S. Pat. No. 3,736,762 discloses a process for producing nitrogen in gaseous and liquefied form from air. A single distillation column is refluxed with nitrogen product condensed in an overhead condenser operated by the reboil of impure oxygen conveyed from the bottom of said column. At least a portion of the impure oxygen from the overhead condenser is expanded to produce refrigeration for the process.
U.S. Pat. No. 3,754,406 discloses a process for the production of low purity oxygen, in which a low pressure stream of incoming air is cooled against outgoing gas streams and fed into a high pressure distillation column. A high pressure stream of incoming air is cooled against outgoing gas stream, partially condensed against boiling oxygen product in a product vaporizer, and separated into gas and liquid streams. The liquid stream being subcooled and expanded into a low pressure fractionating column. The gas stream is reheated and expanded to provide process refrigeration and is introduced into the low pressure fractionating column. Crude liquid oxygen from the bottom of the high pressure column is cooled and introduced into the low pressure column after being used to liquefy some of the nitrogen from the high pressure column in an external reboiler condenser. Liquid oxygen product from the low pressure column is pumped to a higher pressure before being passed to the subcooler and the product vaporizer. The remainder of the high pressure nitrogen is liquefied in a second external reboiler/condenser and is used as reflux for the two columns. A waste nitrogen stream is removed from the low pressure column.
U.S. Pat. No. 4,222,756 discloses a process in which a two pressure distillation column is used in which both pressurized column sections are refluxed with a nitrogen-enriched stream. The low pressure column is fed by a oxygen-enriched stream from the high pressure column which is expanded to reduce its pressure and temperature.
U.S. Pat. No. 4,224,045 discloses a process where oxygen is produced by distillation of liquefied air in a two column unit. A gas turbine, powered in part by a nitrogen product stream, supplies the energy to compress the feed air.
U.S. Pat. No. 4,382,366 discloses an air separation system for the recovery of pressurized, substantially pure oxygen gas. The system uses a single pressure distillation column and burns a nitrogen-oxygen waste stream to provide power for the air compressor, the oxygen product compressor and electric generation. The distillation column has a split feed to develop reflux and reboil and to provide initial separation of the liquid and vapor components of the column.
U.S. Pat. No. 4,400,188 discloses a nitrogen production process wherein a single nitrogen recycle stream refluxes a distillation column which is fed by a single air feed. Waste oxygen from the column is expanded to provide a portion of the necessary refrigeration.
U.S. Pat. No. 4,464,188 discloses a process and apparatus for the separation of air by cryogenic distillation in a rectification column using two nitrogen recycle streams and a sidestream of the feed air stream to reboil the column. One of the nitrogen recycle streams is expanded to provide refrigeration and to provide power to compress the feed air sidestream.
U.S. Pat. No. 4,464,191 discloses an arrangement of distillation columns for subambient distillation of mixtures of two non-condensable gases. The two column arrangement which exchange liquid achieves a given level of separation over a smaller temperature range than a single column producing the same separation. The arrangement of the patent is particularly useful for air separation to produce medium purity (90 to 99%) oxygen and/or nitrogen.
U.S. Pat. No. 4,560,397 discloses a process for the production of ultra high purity oxygen and elevated pressure nitrogen by the cryogenic rectification of air wherein the product oxygen is recovered from a secondary column at a point above the liquid sump while impurities are removed from the column at a distance from the product withdrawal point.
U.S. Pat. No. 4,617,036 discloses a process for the cryogenic distillation of air to recover nitrogen in large quantities and at relatively high pressure, wherein a portion of the nitrogen reflux for the distillation is achieved by heat exchanging nitrogen gas in a side reboiler against waste oxygen at reduced pressure.
U.S. Pat. No. 4,617,037 discloses a nitrogen production method wherein air is compressed, is removed of water and carbon dioxide contained therein, and is simultaneously cooled to a temperature close to the liquefying point. The resultant cleaned and cooled air is fed into a rectifying column for rectification so that high purity nitrogen is removed from the rectifying column overhead and the oxygen-enriched liquid air is withdrawn from the rectifying column bottom and is expanded and fed into a condensation step wherein it becomes a source of reflux for the rectifying column and a source of refrigeration. In the method of the patent, a closed circulating cycle provides additional refrigeration.
U.S. Pat. No. 4,655,809 discloses an air separation system for the recovery of pressurized, substantially pure oxygen gas. The system uses a single pressure distillation column and utilizes the nitrogen product stream to provide power for feed air compression, segregated heat pump fluid compression, and electric generation. The system utilizes a segregated heat pump cycle which provides heat exchange for both column reboil and reflux.
U.S. Pat. No. 4,662,916 and 4,662,917 disclose variations on a process for the separation of air by cryogenic distillation in a single column to produce a nitrogen product and an oxygen-enriched product. In the process, at least a portion of the nitrogen product is compressed and recycled to provide reboil at the bottom of the distillation column and to provide some additional reflux to the upper portion of the column. In addition, part of the compressed air stream is expanded to provide work, which is used to drive an auxiliary compressor for recycle nitrogen stream compression.
U.S. Pat. No. 4,662,918 discloses a process for the separation of air by cryogenic distillation in a single column to produce a nitrogen product and an oxygen-enriched product. In the process, at least a portion of the nitrogen product is compressed and recycled to provide reboil at the bottom of the distillation column and to provide some additional reflux to the upper portion of the column. In addition, part of the compressed nitrogen recycle stream is expanded to provide work.
U.S. Pat. No. 4,702,757 discloses a process utilizing high and low pressure distillation columns for the production of an oxygen-enriched air product. Feed air is fed to the main heat exchangers at two pressures. The high pressure feed air from the main exchanger used to supply refrigeration, by expanding a portion of the high pressure air prior to introducing that portion into an intermediate location in the low pressure column, and to vaporize the oxygen-enriched air product prior to using the stram as reflux for the high pressure column. The low pressure feed air from the main heat exchangers is partially condensed to supply reboiler duty to a low pressure column and is then fed to a high pressure column. The high pressure column condenser is used to reboil an intermediate liquid in the low pressure column.
U.S. Pat. No. 4,704,147 discloses a process for the production of an oxygen-enriched air product, feed air is fed to the main heat exchangers at two pressures. The high pressure feed air from the main exchanger is partially condensed to vaporize the oxygen-enriched air product. This partially condensed feed air is separated with the vapor phase being warmed and expanded to supply refrigeration and subsequently being fed to the low pressure fractionation section, and the liquid phase being used to reflux both the high pressure and low pressure fractionation sections of a double distillation column. The low pressure feed air from the main heat exchangers is fed to the high pressure fractionation section. The high pressure fractionation section condenser is used to provie reboiler duty to the low pressure fractionation section.
U.S. Pat. No. 4,704,148 discloses a process utilizing high and low pressure distillation columns, for the separation of air to produce low purity oxygen and waste nitrogen streams. Feed air from the cold end of the main heat exchangers is used to reboil a low pressure distillation column and to vaporize the low purity oxygen product. This heat duty for column reboil and product vaporization is supplied by splitting the air feed into at least three substreams. One of the substreams is totally condensed and used to provide reflux to both the low pressure and high pressure distillation column, preferably the substream which is fed to the oxygen vaporizer, while a second substream is partially condensed with the vapor portion of the partially condensed substream being fed to the bottom of the high pressure distillation column and the liquid portion providing reflux to the low pressure column. The third substream is expanded to recover refrigeration and then introduced to the low pressure column as column feed. Additionally, the high pressure column condenser is used as an intermediate reboiler in the low pressure column.
SUMMARY OF THE INVENTION
The present invention is an improvement to a nitrogen generator process that utilizes a single cyrogenic distillation column to produce nitrogen, wherein refrigeration for the process is provided by a waste expander or an air expander. Basically, the improvement comprises integrating a secondary distillation column into the process to produce small quantities of high purity oxygen. In operating the process with the secondary column, a portion of oxygen-rich liquid from the sump of the nitrogen generator column overhead condenser is removed and fed to an upper location of the secondary column. Reboil for the secondary column is provided by condensing a portion of nitrogen overhead from the nitrogen generator column in a reboiler/condenser located in the bottom of the secondary column. At least a portion of the condensed liquid nitrogen from the reboiler/condenser located in the bottom of the secondary column is used to provide reflux to the nitrogen generator column. Under some modes of operation, part of this liquid nitrogen can be removed from the process and sent to storage as product liquid nitrogen. The high purity oxygen co-product is recovered from the secondary column at a point in the secondary column above and/or below the reboiler/condenser.
This high purity oxygen co-product is recovered from a waste stream normally vented to the atmosphere in the nitrogen generator proess, without additional operating power or air feed requirements.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic drawing of the process of the present invention for the production of nitrogen and small quantities of high purity oxygen.
FIG. 2 is a schematic drawing of the process of U.S. Pat. No. 4,560,397, which has been slightly modified to incorporate a reversing heat exchanger and liquid oxygen production.
FIG. 3 is a schematic drawing of an alternate embodiment of the process of the present invention for the production of nitrogen and small quantities of high purity oxygen.
DETAILED DESCRIPTION OF THE INVENTION
There is a need by many users of nitrogen to also have a small supply of high purity oxygen. Typically, the requirement for oxygen is too large to be supplied economically from vaporized liquid oxygen and too small to justify the installation of a separate cryogenic oxygen generator. The concept of a nitrogen generator modified to produce a small amount of high purity oxygen without significant power and capital penalties would be very advantageous for this type of user. The present invention is a solution to this problem.
The present invention is an improvement to a nitrogen generator air separation process utilizing a conventional cryogenic single distillation column nitrogen generator, wherein refrigeration for the process is provided by either a waste expander or an air expander. A nitrogen generator air separation process is one in which air is separated by cryogenic distillation to produce one or more nitrogen product streams and typically the oxygen constituent in the air is removed as a waste stream. Examples of nitrogen generator air separation processes are shown in U.S. Pat. Nos. 3,217,502; 3,735,599; 3,736,762 and 4,617,037, the specifications of which are incorporated herein by reference. Basically, the improvement is the integration of a secondary oxygen column into the nitrogen generator process to produce a high purity oxygen co-product. The high purity oxygen co-product is recovered from the waste stream from the nitrogen generator process, this stream would normally be vented to atmosphere. Oxygen is produced with no additional operating power or air feed requirements. The process of the present invention produces its nitrogen product at elevated pressures, thus for most applications, eliminating the need for product nitrogen compression.
To accomplish the production of the high purity oxygen co-product, a portion of the oxygen-rich liquid from the sump of the nitrogen generator column overhead condenser is fed to an upper location f the secondary column. Reboiling for the secondary column is provided by condensing a portion of the nitrogen overhead from the nitrogen generator column in a reboiler/condenser located in the bottom of the secondary column. The condensed nitrogen liquid is used to provide reflux to the nitrogen generator column, and in some modes of operation, part of the liquid nitrogen can be removed from the process as liquid nitrogen product.
The limit on the amount of oxygen that can be produced is determined by the overall refrigeration requirements for the process. Increasing the feed to the secondary column reduces the amount of boil-up vapor from the reboiler/condenser which feeds the expansion turbine. Large liquid nitrogen and/or oxygen requirements require large expander flows and therefore limit the feed available to the secondary column. Nitrogen recovery, oxygen purity and operating pressure influence the flow requirements for the expansion turbine and thereby affect the oxygen recovery by changing the feed available to the secondary column.
Oxygen recovery can be further increased by one of the following modifications. (1) Liquid nitrogen from an external source can be fed to the main distillation column as reflux, thereby providing additional refrigeration to the process. This additional external refrigeration would decrease the flow required by the expansion turbine and thereby increase the flow available to the secondary column. (2) An expansion turbine could be used to replace the expansion valve which reduces the pressure of the overhead from the secondary column prior to its venting as waste. This work expansion of the secondary column overhead stream (or at least a portion thereof) would provide additional refrigeration to the process and thereby increase the flow available to the secondary column.
Although so far discussed with reference to nitrogen generator process systems which utilizes a single cryogenic distillation column, the present invention is also applicable to nitrogen generator systems which utilizes a double cryogenic distillation column. Examples of double column nitrogen generators are disclosed in U.S. Pat. Nos. 4,222,756; 4,453,957 and 4,617,036, the specifications of which are incorporated herein by reference. In the operation of the process of the present invention in a double column system, liquid feed to the secondary column would be drawn from the main reboiler/condenser space or, where applicable, the top reboiler/condenser.
FIG. 1 shows a preferred embodiment of the process utilizing a single distillation column which produces nitrogen and oxygen at the highest pressure. With reference to FIG. 1, filtered air is fed via line 1 to compressor 3 and compressed to an elevated pressure. This filtered and compressed air is then cooled to cooling water temperatures before entering main heat exchangers 7 and 9 via line 5 (this stage of cooling is not shown). The air is cooled to near its dew point in main exchangers 7 and 9 by indirect heat exchange with the returning products and waste streams. Heat exchangers 7 and 9 could be either reversing heat exchangers to provide water and carbon dioxide removal or non-reversing heat exchangers when front end adsorption systems are used to remove water and carbon dioxide impurities. The cooled air enters nitrogen generator column 13 via line 11 and is separated into a high purity nitrogen overhead and an oxygen-rich bottoms liquid.
A portion of the nitrogen overhead is removed from nitrogen generator column 13 via line 44 and fed to overhead condenser 43 wherein it is condensed and removed via line 45. The remainder of the nitrogen overhead is removed from nitrogen generator column 13 via line 51. This nitrogen stream is split into two substreams, lines 53 and 81, respectively. First substream 53 is fed to reboiler/condenser 55, located in the bottom of secondary column 39, wherein it is condensed and removed as liquid nitrogen via line 57. The liquid nitrogen in lines 45 and 57 are combined, a portion of the combined liquid nitrogen is removed as liquid nitrogen product via line 61; the remainder is fed to the top of nitrogen generator column 13 as reflux. Second substream 81 is heat exchanged in heat exchangers 19, 9 and 7 to recover refrigeration and removed from the process as gaseous nitrogen product via line 83.
A small air sidedraw is removed from nitrogen generator column 13 via line 17 and condensed in heat exchanger (superheater) 19. The condensed sidedraw, now in line 21, is combined with crude liquid oxygen, in line 15, from the bottom of nitrogen generator column 13. This combined stream, line 23, is subcooled in heat exchanger 19 and flashed in valve 25 (forming a two phase mixture) before being fed to overhead space 29 of nitrogen generator column 13 via line 27.
A portion of the oxygen-rich liquid in overhead space 29 is removed via line 33, flashed in valve 35 and fed to the top of secondary column 39 via line 37. The remainder of the oxygen-rich liquid in overhead space 29 is vaporized by the condensing nitrogen in reboiler/condenser 43 and removed from column 13 via line 93. This stream 93 is partially warmed in superheater 19. The warmed stream, now in line 95, is split into two substreams, lines 97 and 101, respectively. Substream 97 bypasses heat exchanger 9 by passing through valve 99 and is reunited with substream 101 which has been warmed in heat exchanger 9. The reunited stream, now in line 103, can be split into two portions. First portion 105 is work expanded in expander 107 forming stream 109. Second portion 111 is expanded in valve 113, the amount of material flowing in stream 111 will inversely depend on the amount of oxygen produced by the process. These expanded portions, lines 109 and 115, are combined with the overhead from secondary column 39, via line 91 after passing through pressure reducing valve 92, thereby forming combined stream 117. This valve (92) can also be an expansion turbine, as shown as expander 192 in FIG. 3, and thereby increase the amount of refrigeration available to the process. FIG. 3 is identical to FIG. 1 with the exception that pressure reducing valve 92 has been replaced with expansion turbine 192. This combined stream 117 is warmed in heat exchangers 19, 9 and 7 and removed from the process as a waste stream via line 119.
The feed to the top of the secondary column, line 37, is separated in secondary column 39 to produce high purity oxygen, which is removed as liquid oxygen product from the bottom (71) of column 39 via line 73 and as gaseous product via line 75. The gaseous product is then warmed in heat exchangers 19, 9 and 7 to recover refrigeration and removed as oxygen product from the process via line 77.
As mentioned earlier, water, carbon dioxide and other impurities which may freeze out at cryogenic temperatures can be removed by the use of a reversing heat exchanger or by the use of a front end molecular sieve absorber system. Both the molecular sieve system and the reversing heat exchanger system will provide adequate removal of impurities which freeze out at cryogenic temperatures for this process. Neither system has any significant advantages over the other.
The concept of using a secondary column to produce oxygen from a nitrogen generator process can be applied to basically any nitrogen generator process currently in use today.
The process of the present invention has numerous benefits, among these are the following. The process eliminates the requirement for a second cryogenic air separation plant to produce oxygen or the need to haul in liquid oxygen at sites where a nitrogen plant is needed. The invention is able to produce a small supply of high purity oxygen from a single cryogenic process which produces high purity nitrogen at elevated pressure as the primary product. The nitrogen product is produced at an elevated pressure (essentially main column pressure) which eliminates the need for nitrogen product compression in many applications. Elimination of nitrogen compression is a major advantage over a conventional low pressure oxygen generator which also produces low pressure nitrogen. The oxygen pressure is also at an elevated pressure (relative to a small, conventional oxygen plant process) which will save on oxygen compression costs. The process produces liquid oxygen product that can be stored for later use during plant outages. This invention also has the advantage that if oxygen is not required, the oxygen equipment can be taken out of service and the process can be operated as a conventional nitrogen generator. Additionally, the process can be operated to produce a low purity oxygen product for those applications where high purity oxygen is not required.
In order to demonstrate the efficacy of the present invention and to provide a comparison with the best available prior art, the following examples (computer simulations) were prepared.
EXAMPLE 1
The process of the present invention, as depicted in FIG. 1, was computer simulated to produce a maximum oxygen product. Table I lists operating conditions and stream flows and compositions for selected streams.
TABLE I__________________________________________________________________________Material Balance and Operating Conditions for Selected StreamsProcess of the Present InventionStream Temperature: Pressure: Total Flow: Component Flow Rates: lb-mol/hrNumberPhase °F. psia lb-mol/hr Nitrogen Argon Oxygen__________________________________________________________________________ 1 VAP AMBIENT 14.7 100.00 78.12 0.93 20.95 5 VAP 98.0 133.5 100.00 78.12 0.93 20.9511 VAP -265.4 131.2 100.00 78.12 0.93 20.9515 LIQ -268.1 131.2 56.01 34.69 0.90 20.4217 VAP -268.1 131.2 2.54 1.98 0.03 0.5323 LIQ -274.2 131.2 58.55 36.67 0.93 20.9533 LIQ -280.8 77.6 39.49 22.11 0.70 16.6853 VAP -276.7 127.5 47.23 47.23 0.00 0.0057 LIQ -276.7 127.5 47.23 47.23 0.00 0.0061 LIQ -276.7 127.3 0.39 0.39 0.00 0.0073 LIQ -281.9 33.0 0.20 0.00 0.00 0.2077 VAP 92.3 30.4 7.80 0.00 0.03 7.7781 VAP -276.7 127.5 41.06 41.06 0.00 0.0083 VAP 92.3 124.4 41.06 41.06 0.00 0.0091 VAP -296.9 31.0 31.49 22.11 0.67 8.7193 VAP -280.9 77.6 19.06 14.56 0.23 4.2795 VAP -270.1 77.0 19.06 14.56 0.23 4.2797 VAP -270.1 77.0 6.06 4.63 0.07 1.36105 VAP -182.5 76.0 18.75 14.32 0.23 4.20109 VAP -258.0 19.5 18.75 14.32 0.23 4.20111 VAP -182.5 76.0 0.31 0.24 0.00 0.07117 VAP -284.3 19.2 50.55 36.67 0.90 12.98119 VAP 92.2 14.7 50.55 36.67 0.90 12.98__________________________________________________________________________
EXAMPLE 2
In order to provide a comparison of the present invention to the closest prior art process, the process cycle of U.S. Pat. No. 4,560,397, as depicted in FIG. 2, was computer simulated to produce maximum oxygen product. The process of U.S. Pat. No. 4,560,397 has been slightly modified to be suitable for a reversing heat exchanger design and liquid oxygen production. Basically, the process of U.S. Pat. No. 4,560,397 is similar to that of the present invention except in several key elements. The differences are evident from the following discussion.
With reference to FIG. 2, the oxygen-rich stream 23 is split into two portions following flashing in valve 25. A first portion is fed to overhead space 29 via line 127 and a second portion, line 133, is flashed in valve 35 and fed to secondary column 39 via line 37. Also a liquid purge stream is withdrawn from overhead space 29 via line 120. The remaining streams are the same as in FIG. 1 and have been assigned common numbers. Table II lists operating conditions and stream flows and compositions for selected streams.
TABLE II__________________________________________________________________________Material Balance and Operating Conditions for Selected StreamsPrior Art Process (U.S. Pat. No. 4,560,397)Stream Temperature: Pressure: Total Flow: Component Flow Rates: lb-mol/hrNumberPhase °F. psia lb-mol/hr Nitrogen Argon Oxygen__________________________________________________________________________ 1 VAP AMBIENT 14.7 100.00 78.12 0.93 20.95 5 VAP 98.0 133.5 100.00 78.12 0.93 20.9511 VAP -265.1 131.2 100.00 78.12 0.93 20.9515 LIQ -268.1 131.2 55.76 34.49 0.90 20.3717 VAP -268.0 131.2 2.79 2.18 0.03 0.5823 LIQ -274.2 131.2 58.55 36.67 0.93 20.9553 VAP -276.7 127.5 37.10 37.10 0.00 0.0057 LIQ -276.7 127.5 37.10 37.10 0.00 0.0061 LIQ -276.7 127.3 0.39 0.39 0.00 0.0073 LIQ -281.9 33.0 0.20 0.00 0.00 0.2077 VAP 92.6 30.4 5.75 0.00 0.03 5.7281 VAP -276.7 127.5 41.06 41.06 0.00 0.0083 VAP 92.6 124.4 41.06 41.06 0.00 0.0091 VAP -298.6 31.0 27.45 20.92 0.50 6.0393 VAP -281.0 65.1 24.95 15.67 0.40 8.8895 VAP -270.1 64.4 24.95 15.67 0.40 8.8897 VAP -270.1 64.4 11.95 7.51 0.19 4.25105 VAP -201.9 63.4 24.77 15.56 0.40 8.81109 VAP -264.4 19.5 24.77 15.56 0.40 8.81111 VAP -201.9 63.4 0.18 0.11 0.00 0.07117 VAP -284.3 19.2 52.40 36.59 0.90 14.91119 VAP 92.6 14.7 52.40 36.59 0.90 14.91120 LIQ -280.9 65.0 0.20 0.08 0.00 0.12133 LIQ -274.2 131.2 33.40 20.92 0.53 11.95__________________________________________________________________________
As can be seen, a similar process described in U.S. Pat. No. 4,560,397 produces both high purity nitrogen and oxygen from a cryogenic air separation process. This process employs a single column nitrogen generator cycle with a secondary column to produce ultra high purity oxygen. Although there are many similarities between this process and the process of the present invention, there are also some significant differences:
The process of the present invention feeds all of the liquid from the bottom of the main column to the overhead reboiler/condenser and then feeds liquid from the reboiler/condenser to the secondary column. This extra step enriches the feed to the secondary column and reduces the number of theoretical distillation stages required or increases product recovery with the same number of distillation stages. Patent 4,560,397 splits the liquid from the bottom of the main column between the reboiler/condenser and the secondary column. This does not take advantage of the oxygen enrichment in the reboiler/condenser.
Additionally, feeding the secondary column from the reboiler/condenser causes the liquid phase to be richer in nitrogen (about 56% N2) than the liquid phase in the reboiler/condenser of the process in Pat. No. 4,560,397 (about 39% N2). The higher concentration of nitrogen allows the reboiler/condenser to operate at a higher pressure and thus a higher inlet pressure to the expansion turbine. This higher pressure will result in more refrigeration available for liquid production. Also, for a fixed refrigeration load, this higher pressure will reduce the expander flow and increase the flow available to the secondary column resulting in an increase in oxygen production.
Another difference of U.S. Pat. No. 4,560,397, as depicted in the patent itself, is the use of a mechanical pump to return some of the liquid from the bottom of the secondary column to the reboiler/condenser on the main column. The proposed process eliminates the mechanical pump by continuously withdrawing a liquid oxygen stream from the bottom of the secondary column. This stream can be stored as liquid oxygen or vaporized and used as gaseous product. Eliminating the pump reduces the maintenance associated with pumps and improves the overall reliability and efficiency of the process.
These differences result in a major difference in the amount of oxygen product which can be produced by the two processes. The process of the present invention can produce, when operated in a maximum oxygen production mode, 7.8 lb-mols of high purity gaseous oxygen and 0.2 lb-mols of high purity liquid oxygen for every 100 lb-mols of air fed to the process. On the other hand, the process of U.S. Pat. No. 4,560,397, when operated in a maximum oxygen production mode, can only produce 5.75 lb-mols of high purity gaseous oxygen and 0.2 lb-mols of high purity liquid oxygen for every 100 lb-mols of air fed to the process. This is an increase of over 34% in the amount of high purity oxygen producible by the process of the present invention, i.e. a 34% increase in production without an increase in air feed to the process, a reduction in the amount of nitrogen product, or an increase in the energy required to drive the process. This difference is a significant improvement in the art.
The present invention has been described with reference to a specific embodiment thereof. This embodiment and its supportive example should not be considered a limitation on the scope of the invention, such scope should be ascertained by the following claims. | The present invention relates to a process to produce large quantities of pure nitrogen and small amounts of high purity oxygen co-product which utilizes a modified single distillation column nitrogen generator. The modification is the addition of a small second column which purifies a portion of the oxygen enriched liquid from the nitrogen generator overhead condenser. Reboiling for the second column is provided by condensing part of the nitrogen overhead from the nitrogen generator. This condensed nitrogen is used as reflux in the nitrogen generator. | 5 |
FIELD OF THE INVENTION
The present invention relates to an endless flat band for use as a transmission belt, for example as a conveyor belt or the like, containing a spirally extending, straight pulling element in the form of a thread or a wire extending in the direction of movement of the band and having a transverse connection by means of loops and at least partially by means of a binding agent, wherein at least one spiral of the pulling element is inserted into a tubular fabric in a knitting machine.
The invention further relates to a process for producing such an endless flat band.
BACKGROUND OF THE INVENTION
A manufacturing process for an endless transmission belt on a flat bed knitting machine is described in German Patent DE-PS 12 84 734. Transmission and conveyor belts manufactured in this way cannot be used optimally everywhere, because the thread position of the weft thread, for example, unavoidably has a certain amount of waviness by reason of the insertion, necessary for production, of the weft thread in the form of a tuck loop. Because of this wave-shaped thread insertion the final belt length can be determined only empirically and cannot be exactly predetermined during production. For this reason it is necessary to prepare samples at the start of a production run in order to determine the exact belt length.
Another disadvantage of this fabric is its asymmetric structure. Because the fabric is produced as tubular goods, there always is a single-faced right/left knitting construction with side-by-side wales. These wales cause formation of ribs, especially with coarse fabrics made to an E8 or E6 gauge, i.e. six to eight needles/inch for heavy transmission belts, which result in development of considerable running noises when the belt is used at high speeds.
Because of the insertion of the weft thread in a tuck loop and the wave-shaped deformation of the thread caused thereby, it is difficult to maintain the thread insertion exactly the same across the fabric width as well as the thread insertion between the front needle bed and the rear needle bed. These different thread insertions cause differences in tension within the finished belt, which result in a considerable impairment of the straight running of the belt. But even the introduction of a double thread can only be done with great effort and with a loss of the quality of the finished endless belt. Multiple thread crossings are caused by the uncontrolled insertion of the double thread, which results in an erratic mesh pattern and, in particular, in differences in tension within the individual threads. This is particularly critical if it is intended to process materials of different yarn twists together in a known manner, for example left-hand twisted "S" and right-hand twisted "Z", to improve the straight running of the endless belt.
It is known that the yarn twist of a thread affects an endless belt in such a way that, when it runs over two parallel cylindrical disks it always runs in the respective direction of twist of the carrier thread. For this reason it is known to insert two threads in parallel. However, when employing two threads with S-twist and Z-twist, the insertion becomes uncontrolled in the normal right/left knitting construction with thread couliering and, as a result, there is frequent ride-over or twisting of the two threads. This naturally leads to an irregular final appearance of the goods and to thickening at the ride-over points.
It is known from German Patent DE-PS 88 324 to produce a right/right tubular fabric with weft threads on a flat bed knitting machine (FIGS. 1, 2). However, auxiliary needles and narrowing combs are needed for freeing a path for the weft thread. Since there is no needle division and all needles C 1 always operate, it is necessary to transfer the loops of the auxiliary needles laterally to the needles C 1 .
It is further known to those skilled in the art that it is impossible to produce a symmetrical tubular fabric on a conventional flat bed knitting machine.
To produce a useful fabric and to achieve a somewhat efficient production, the machine should be equipped with electronic needle selection and at least three knitting systems connected one behind the other.
SUMMARY OF THE INVENTION
Taking account of the above prior art, it is an object of the invention to provide improved endless flat bands, as well as a process for their production, of the type mentioned at the outset.
A more specific object of the invention is to provide a symmetrical fabric which can form a flat band having an increased service life.
In connection with the endless flat band, this object is attained by means of an endless flat band for use as a transmission belt which has a direction of movement, said band comprising: a spirally placed, straight pulling element in the form of a thread or a wire extending in the direction of movement of the belt: and a transverse connection composed of a tubular fabric which has thread loops and at least partially of a binding agent, wherein at least one turn of the pulling element is inserted into the tubular fabric in a knitting machine, wherein the at least one turn of said pulling element is inserted already straightened into a right/right transfer construction between loops or loops and tuck loops.
Objects according to the invention are further achieved by a process for manufacturing the endless flat band described above in a knitting machine having divided needles: comprising knitting the tubular fabric on the divided needles, inserting the pulling element as a weft thread during knitting, and transferring loop threads back to a binding needle.
In the process, defined needles or groups of needles of the front and rear needle bed are covered with loops in such a way that the selected needles always cooperate by means of the transfer technique with the opposite needles located on the other side, so that a typical knit pattern repeat would consist of the following steps:
1. divide the needles;
2. Knit;
3. Insert the weft and transfer the divided loops.
A symmetrical fabric is obtained by means of this knitting process, which makes it possible to employ a great variation of different weft thread thicknesses without problems.
The pulling element can be freely inserted and does not have to be couliered by means of the needles. The final belt length (circumference of the thread spiral) can also be exactly predetermined and no longer needs to be determined empirically. Length differences are avoided in that the carrier element (weft thread) can be inserted with an exactly defined tension.
The symmetrical loop formation is another advantage in comparison to the endless knitted tubes for flat belts known up to now. A tension equalization is created because of a quasi right/right loop formation achieved by means of the transfer knitting, preventing the increased tension on the loop side which would lead to excessive curling at the fabric edge and otherwise occurs in connection with one-sided, asymmetric right/left knitting constructions. This results in an important advantage in the further processing of the fabric tube, because the additional smoothing of the knitted edges is omitted or a stiffening of the knitted edge is no longer necessary.
In addition, with an embodiment in which the pulling element comprises at least one thread twisted in the S-direction and at least one thread twisted in the Z-direction, the threads extending parallel to, and lying adjacent, one another in the fabric, it is possible to insert two threads in parallel. When working with two threads, the threads preferably have an S-twist and a Z-twist in alternation.
In the process it is possible to insert the two thread guide elements or thread guides in such a way that there is almost no thread ride-over at all. Another possibility of designing the thread insert in an even more precise manner is to employ separately controlled thread guides for the thread with the S-twist and the thread with the Z-twist.
With an embodiment in which the pulling element has at least one temperature-resistant thread and a least one plastic thread with a low melting point, it is possible to combine different materials. An example of this is a combination of a Kevlar™ carrier thread and a fusible polyamide thread. In this case, pre-bonding of the fabric is achieved, for example in a subsequent process, by fusing the fusible thread.
In a further embodiment, the pulling element has a highly elastic thread which has an elasticity or elongation greater than 20% after the tubular fabric is finished and the thread loops preferably consist of a material having a lower degree of elasticity than the elastic thread of the pulling element. In this case, the transfer knitting construction makes it possible to produce an endless flat band which has very great elasticity in a defined area which, however, is definitely limited. This is achieved in that the pulling element (weft thread) has a highly-elastic rubber or spandex thread or a thread made of other highly elastic materials, which preferably is covered with thread and has an elongation at tear greater than 100%, and an inelastic loop thread with an elongation at tear of maximally 25%. In the course of the stretching of the pulling element, the loop geometry of the knitted net also changes, and the tube or the flat band made from it experiences a natural elongation limitation when the loop geometry has changed sufficiently so that the shank of the loop of the needle loop completely rests against the carrier thread and the shank of the sinker loop has been elongated up to its end position. The elongation limitation can be changed by changing the couliering of the loop. In this case, longer loop shanks result in increased elongation.
Further advantages will be described below. The invention will be described in detail below by reference to schematic process progressions shown in FIGS. 1 to 7.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a thread progress diagram of a transfer weft knitting construction with loops only.
FIG. 2 is a thread progress diagram with alternating loops and tuck loops.
FIG. 3 is a thread progress diagram with loops and tuck loops, wherein a guide bar has been additionally pre-manufactured by working in a wave.
FIG. 4 is a thread progress diagram with loops only.
FIG. 5 is a thread progress diagram with loops and tuck loops, in which additional ribs or knobs are generated by means of the needle selection.
FIG. 6 is a schematic representation of a thread spiral worked into the knitted fabric.
FIG. 7 is a pictorial view of a fabric produced in the manner illustrated in FIG. 1, having weft threads of different twist.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
An endless flat band or knitted tube in the described transfer knitting construction is preferably produced on an electronically-controlled single- or multiple-system flat bed knitting machine. The computer-controlled regulation of the knitting systems of the needle guides and the needle selection permits a plurality of knitting construction variations which, however, are all based on the basic principle of knitting on divided needles, insertion of the weft thread and transfer of the loop shank to the construction needle. This includes an absolutely tension-free feeding of the weft thread. This is achieved by means of thread feeding devices, so-called feed-wheel mechanisms, which are particularly adapted to this knitting process.
To achieve even more accurate thread tension, it is possible to employ electronic servo motors which drive a feed-wheel mechanism and are con,rolled by an electronic thread tension measuring unit. The exact control of the thread tension of the weft thread is of decisive importance for high quality of the tubular fabric.
The described knitting construction forms the basis of many variation options, which can be changed by means of a different needle spacing, or division, or needle selection and changes in the knitting construction in the knitting rows. The knitting construction can be especially varied in that a plurality of rows of loops of different construction and needle selections are knitted in the form of intermediate rows between the weft insert.
FIG. 1 is a thread progress diagram of a transfer knitting construction with only loops. With the construction shown here, a pattern repeat of four needles to be selected is necessary, which needles are designated by A, B, C, D for, respectively, front and rear needle beds. Only the cooperation between the needles in the front and rear needle beds leads to the knitting construction shown in FIG. 1. The needles A and C in the rear needle bed or the needles B and D in the front needle bed are respectively covered by loops and represent the initial situation for the construction shown. A finished knitted row is formed by the operations depicted in function blocks consisting of diagram sections 1 to 4, wherein each section illustrates three operations a, b and c. These operations are the following:
a: Dividing of the selected needles by means of transfer and applying a weft thread (carrier thread) to the loops spread over the two needle beds,
b: Knitting by means of the selected needles--loop only,
c: Transferring the divided loops back to the initial needles in the rear needle bed.
Diagram section 2 basically shows the same operation, except that the initial knitting row is in the front needle bed and the needles are selectively divided in the rear needle bed.
Diagram section 3 shows the same operation as diagram section 1. In place of the loop on the needle A, the loop of the needle C is transferred to the selected needle C in the front needle bed.
Diagram section 4 is the same as diagram section 2, but again the loop on the needle D, instead of the loop on the needle B, is transferred to the selected needle D in the rear needle bed. The progression of knitting of the diagram sections 1 to 4 forms a complete knitting construction in which the result is a respective alternation of left and right loops, by means of which a relatively solid fabric is formed. In principle, the construction can also be made only by operations depicted in the diagram sections 1 and 2.
FIG. 2 differs from FIG. 1 in that the construction is made of loops and tuck loops which are formed in alternation. In this construction variant, a finished knitted row always requires the steps depicted in the four diagram sections shown.
The following operations are shown in diagram sections 1a, 1b and 1c:
1a. Selection of each fourth needle, indicated by A in diagram section 1,
transfer of this loop to the opposite needle A and application of the weft thread (carrier thread).
1b. Selected needles knit loops in the rear needle bed and tuck loops in the front needle bed.
1c. Transfer of the divided loops from the front needle bed to the initial needle in the rear needle bed.
Diagram section 2 shows the same operation, only here the loops in the front needle bed are transferred to the rear on the selected counter-needle. Diagram sections 3 and 4 represent the oppositely offset function selection.
Twelve diagram sections are illustrated in FIG. 3, wherein the diagram sections 1 to 4 are the same as diagram sections 1 to 4 of FIG. 2. However, by means of inserting a wave, an additional guide bar is premanufactured for the belt or conveyor belt which is to be made from it later. The rear loops of the wave are prepared by the functions shown in diagram sections 5 and 6. The wave is formed by the functions shown in diagram sections 7 and 8, which are usefully repeated several times. The wave is knitted by the functions shown in diagram sections 9 to 12, and the needles for further knitting in transfer tuck loop construction are prepared as shown in diagram section 1 to 4.
FIG. 4 illustrates a further construction variant, wherein diagram sections 1 and 2 illustrate operations in which the selected needles are covered by two rows of loops formed from two successive threads and diagram section 2a shows an operation in which a weft thread (carrier thread) is inserted, and the needles in the front needle bed or the rear needle bed covered by loops are transferred to the corresponding counter-needle. Diagram sections 3, 4 and 4a show succeeding operations which are symmetrical with those of diagram sections 1, 2 and 2a.
FIG. 5 shows how, in addition to the normal transfer tuck loop weft fabric (shown in diagram sections 1 to 4), a rib is worked in. Diagram sections 5, 6 and 7 show the covering with loops of selected needles in the rear needle bed, i.e. three successive threads are formed into loops. Diagram sections 8, 9 and 10 show the same operations in the front needle bed. The loops made by the steps shown in diagram sections 6 to 10 are slightly pulled together at the non-selected needles which remain in the loops, and ribs or knobs are formed. The steps of diagram sections 5 to 10 can be worked into the basic fabric as often as desired to form intermediate rows.
FIG. 6 shows a schematic representation of the thread spiral 10, corresponding to the weft threads of FIGS. 1 to 5, worked into the fabric 11, which is preferably made from a single or a double thread and which is produced by means of the loop forming process described in connection with any one of FIGS. 1 to 5.
FIG. 7 illustrates the fabric produced by the operations shown in FIG. 1, wherein in this case two weft threads with different thread twists, S and Z, corresponding to thread 10 of FIG. 6, respectively, have been inserted.
All knitting processes have in common that it is possible to insert a pulling element in the form of a thread or wire into loops or tuck loops. In this case the pulling element is at least one spiral which, for example, can also have a thread twisted in the S-direction and another twisted in the Z-direction. These two threads are then lying parallel next to each other in the fabric.
The entire flat band can have a transverse connection by means of a binding agent, which increases the service life of the flat band. It is possible for this purpose to insert a temperature-resistant thread and at least one plastic thread with a low melting point into the fabric. For example, the spiral can also be prestressed, or a pulling element can have a highly elastic thread which still has an elasticity of more than 20% after the tubular fabric has been finished. For example, the highly elastic thread can have an elongation of more than 20%, and the loop thread can consist of a material with a lesser elasticity in comparison therewith. For reinforcement it is also possible to employ a metallic thread or wire as the pulling element. Basically, the ratio of the thread thickness of the pulling element to the thread thickness of the loop-forming carrier fabric is 1:1 to 10:1. The carrier fabric is constituted by the threads which form the loops.
The process has already been explained above by reference to thread progress diagrams. The tubular fabric is knitted on divided needles, the weft thread is inserted and subsequently the loop shank is transferred back on the binding needle. The divided loops are transferred after insertion of the weft thread. The needles are divided 1/1, and the tuck loops can be provided in the front and the loops in the back. In the process the weft thread is inserted without needle function, the loops are transferred from the back to the front and another 1/1 selection is made. At the end of this row the weft thread is inserted and transfer to the back is again performed. A plastic thread with a low melting point can be worked in as reinforcement and can be thermally or chemically converted to reinforce the tubular or knitted goods.
This application relates to subject matter disclosed in German Application number P 43 17 652.6, filed on May 27, 1993, the disclosure of which is incorporated herein by reference.
While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention.
The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. | An endless flat band has a spirally placed, straight pulling element in the form of a thread or a wire extending in the direction of movement. A transverse connection is generated by loops and at least partially by a binding agent, wherein at least one spiral of the pulling element is inserted into a tubular fabric in the knitting machine. Because the spiral is inserted already straightened into a right/right transfer construction between loops or loops and tuck loops, it is achieved that a symmetrical fabric is made which increases the service life of the flat band and improves the useful properties. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of Italian Patent Application PD2010A000149, filed on May 11, 2010, and PCT Application PCT/IB2011/052043, filed on May 10, 2011, both incorporated herein by reference.
FIELD OF THE INVENTION
The object of this patent application concerns a molding system with inserts and related product obtained thereby.
DISCUSSION OF RELATED ART
In the field of molding there is a consolidated and well-known method for making molded plastic products, and equally well-known and consolidated is the realization of the relative molds composed of a female die and a male punch. The methods for making a mold are conditioned above all by the costs for making the relative dies, the desire to obtain a pre-set speed for making the products obtained, with a minimum cost of the material used, but with a high quality finish of the products obtained, without there being any evident shrinking and/or deformations. Therefore the realization of products using molds with simple shapes, without any undercuts, is well-known and consolidated.
In the pursuit of relatively new forms, less costly but at the same time more reliable and with a more defined and precise finish, we have the invention which is the object of this patent application. Indeed, when it is necessary to make a die with an undercut, a hollow, like for example a hole, with axes perpendicular to the axes of the movement of the die or the main punch, a cart with relative insert is required. It is evident that such further movement makes the mold more expensive, the removal of the product from the mold slower, and results in a more expensive product. These undercuts and hollows are, however, necessary in the case where a complementary housing for small inserts has to be made, which are inserted into the housings after molding.
Moreover, in addition to the drawbacks set out above, there is also the encumbrance of a successive handling of the product with the insertion, usually manually, of the insert into the specially made housing and the relative fixing, usually using glues. In fact, a dovetail insertion provides no guarantee of a secure seal, something that only specific glues can ensure.
There remains, then, the unresolved issue of an application to the rear of the mold. It is evident that, in the pursuit of ever greater cost-effectiveness, these above-mentioned drawbacks tend to be reduced to a minimum: avoiding the use of inserts in the mold, designing them eventually without any undercuts, creating elements to be inserted that do not have complex forms, with a simple edge, that provide a speedy insertion into the relative housings and by using reliable, non-toxic glues, etc.
For some time now it has been possible to overcome the above-mentioned difficulties and drawbacks with the co-molding of small inserts within the profile of the main products molded. Nevertheless, this co-pressing is complicated and requires expensive molds and equipment.
In the case where simple inserts need to be inserted before the molding, numerous other difficulties arise, in addition to those mentioned above. The main limitation lies in the fact that it is difficult to hold and correctly position these small inserts. Up until today it has not been possible to overcome such difficulties for all types of inserts, especially regarding metallic inserts, whose weight makes them difficult to be restrained, it not being possible to guarantee a defined position, and the precision of the continuous edges and flush with the same surfaces in the profile of the main product being molded. It is clear that if these metallic inserts need to be present on the vertical surfaces, their positioning and precise restraint is difficult to achieve. Also the rotational molding technology is influenced by one or more of the drawbacks mentioned above.
Recently these drawbacks have been partially overcome through the installation of magnets in the male punch or in the female die that hold the above-mentioned metallic inserts. Nevertheless, this method cannot be reversible, with the co-molding of magnetic inserts, since during the operations to remove the products just molded, and still warm, the magnetic insert is forced to follow the movement of the steel mold. This drawback is especially serious in the molding of thin goods, since the material just molded, and still warm, provides minimum resistance, and in any event not enough for the uncontrolled and unwanted movement of the co-molded magnet.
SUMMARY OF THE INVENTION
Technical Problem
The purpose of this patent is to succeed in co-molding plastic objects with magnetic inserts, without the above-mentioned drawbacks and those that will become clear further on in the description.
Technical Solution
It has to do with fitting out the female die or the male punch of a mold with one or more metallic inserts that at least hold an insert to be co-pressed of a magnetic material in the profile of the molded product obtained from said mold using magnetic force.
Advantageous Effects
Advantageously said metallic inserts are positioned inside the profile of the female die or male punch in such a way that sufficient attraction is provided, and the magnetic insert to be co-pressed is restrained in every cycle of the process; thereby providing the precise and secure application of said insert to be co-pressed, providing a secure closing of the mold, maintaining the position of the insert to be co-molded during the entire time the plastic material is injected, ensuring a reliable removal of the product and permitting the final extraction of the molded product itself.
A further advantage of the object of the invention lies in being able to arrange beforehand the positioning of the insert to be co-molded held on the female die or the male punch, thereby increasing the flexibility of the production.
Another advantage consists of the absence of maintenance for the retention devices (inserts associated with one of the parts of the mold), these not being subject to wear.
It is also quite easy to insert and size, also once the female die or the male punch has been made, any additional inserts.
This invention also allows you to easily co-mold said magnetic inserts in positions that would otherwise be complicated or impossible to realize, for example on edges and/or undercuts that would not permit a simple positioning of a ram for a punch.
This application also lends itself in particular to the application of magnetic inserts to be co-molded with the provision that the material of at least one of the parts that make up the mold (die, punch) is made with non-magnetic material, like for example aluminum.
With the above-mentioned application it is possible therefore to obtain goods or products with a co-molded magnetic insert flush with the outer surface or incorporated into the outer perimeter profile. This product, with an eventual co-molded magnetic insert positioned on the surface would be flush, and therefore maintaining a smooth and even surface, eliminating differences of thickness between the support and the co-molded magnetic insert. With these inserts associated with at least one part of the mold there is also the advantage of succeeding in co-molding, in a simple, inexpensive, secure and precise manner a co-molded magnetic insert that will never be subject to detachment, which has no cracks and/or discontinuity along the edges with respect to the support, which is (if underlying) not visible, giving the object a perfect waterproof seal, guaranteed by the continuity of the outer plastic support.
Equally, by using the invention that is the object of this patent application in the rotational mold it is possible to obtain one or more of the above-mentioned advantages with the application of the special metallic inserts on the mold (die) that by force of attraction hold the magnetic inserts to be co-molded on the perimeter surface. It is clear that it is necessary that the insert associated with the mold is metal and that the insert to be co-molded is a magnet. By using the above-mentioned method of co-molding magnetic inserts, you can meet another requirement of realizing molded objects, whose magnet is suspended on a metallic wall or part of it. In fact, even if the co-molded magnetic insert can provide reasonable tensile strength, perpendicular to the suspension surface, it exercises a moderate resistance to sliding along it. This sliding, moreover, especially if the metallic surface has a polished surface finish, and the magnet is flush with the molded product, risks scratching/scraping the surface with unsightly and unacceptable lines.
It is clear that the application of a small felt pad applied using glue on the back, cannot fully resolve the problem since it does not guarantee durability, and a planar application, etc. Moreover a small felt pad creates a sizeable gap, with a consequent reduction in the attractive power of the co-molded magnet with respect to the metallic surface.
Advantageously, the positioning of an underlying magnet allows you to avoid this scratching and streaking of the metallic surface. With this above-mentioned positioning the gap between the magnet and the metallic surface of the application will be very small, and does not significantly reduce the attraction force of the magnet, thereby ensuring a good hold against detachment of the co-molded product with respect to the metallic surface. A further advantage of this underlying positioning consists of the adoption of a co-molded material, or non-slip attached piece, that prevents the co-molded product sliding along the surface of the metallic wall. This non-slip material can be any thermoplastic material and/or that can be joined to the base material of the product, and which has, at room temperature, a reasonable grip on the metallic surfaces, in such a way as to prevent any sliding along the metallic surface of the co-molded product. Advantageously, the use of a metallic sheet placed next to the magnet on the surface opposite that placed near the internal or external profile of the product, allows the lines of magnetic force to be concentrated, and to increase the magnetic attraction with respect to the metallic surface. The methods for co-molding have not been altered, with respect to the adoption of just a single magnet, with the addition of this above-mentioned metallic sheet. This expediency, in addition to the above-mentioned benefits, also allows the space in front of the product to be shielded from undesired magnetic fields, it being possible therefore also to use objects that are sensitive to magnetic fields without any danger of the demagnetization of credit cards, the stopping of watches and medical devices, etc.
Another object of this patent concerns the product molded with a co-molded ferromagnetic insert. Preferably, said co-molded insert is magnetized, and conveniently put near at least one outer perimeter surface.
Advantageously the molded product with a co-molded ferromagnetic insert is directly obtained using the above-mentioned molds.
Advantageously, the above-mentioned co-molded insert has at least one perimetric holding edge with an inclination or configuration that joins it solidly to the molded product and held against any actions or forces that might tend to detach it from the support of the molded product.
Advantageously, the molded product has an underlying magnet.
Another advantage of the molded product is that it has at least in the surface, or part of it, of the side near where the magnetic insert is situated, a non-slip material that prevents any sliding along the metallic surface, the magnetic force being sufficient to provide the necessary resistance to any detachment perpendicular to the surface.
Another benefit of the molded product is that is possesses, next to the magnet on the side opposite to that near the surface, a metallic sheet for concentrating the lines of magnetic force, and increasing the magnetic attraction with regard to the joined metallic surface; and this metallic sheet shields the gap between the molded product from unwanted magnetic fields.
DESCRIPTION OF THE DRAWINGS
By way of example and in no way limiting, the following diagrams show a preferred method with reference to the application of a magnetic insert to be co-molded where the above-mentioned advantages can be seen more clearly and where it is possible to understand further benefits, methods and/or effects.
FIG. 1 shows the invention with reference to a magnetic insert applied to a male punch in the mold closing phase;
FIG. 2 shows the object made with a co-molded magnetic insert in the mold opening phase;
FIG. 3 shows the product of invention with co-molded inserts; and
FIGS. 4 to 10 show different possible ways of positioning one or more magnetic inserts.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The application described in FIGS. 1 and 2 refer to a mold 1 made of a non-ferromagnetic material for the application of a magnetic insert to be co-molded. In particular we can note a longitudinal section of the male punch 3 , the presence of two sunken areas inside which the metallic inserts 4 are inserted that hold the magnetic insert 5 to be co-molded. The positioning of the magnetic insert to be co-molded 5 takes place with the mold 1 open.
In the case in question, on the male punch 3 around the magnetic insert 5 to be co-molded there is a suitable sunken housing 6 for completely surrounding the lateral perimeter of the magnetic insert 5 to be co-molded in the injection resin and to provide an easier extraction later, without the insert to be co-molded 5 being subject to sudden shifts in its position. After the correct positioning of the magnetic insert 5 to be co-molded on the male punch 3 , said male punch 3 , with the magnetic insert 5 to be co-molded held by the metallic inserts in the hollows realized in the body of said male punch 3 , is moved into position inside the female die 2 for the injection of the plastic material. The plastic material fully surrounds the magnetic co-molded insert 5 along the perimeter edges, securely holding the co-molded insert itself in the molded product 7 .
It should be noted that the positioning of said insert 5 to be co-molded is securely held during the entire injection phase. Once the cooling phase of the molded product 7 is complete it is removed with the help of an extractor 8 overcoming the resistance posed by the magnetic forces between the co-molded magnetic insert 5 and the metallic inserts 4 . When the mold 1 is open, the male punch 3 is free and ready for a successive molding cycle.
FIG. 3 shows the molded product 7 with a flush co-molded insert 5 on a face.
FIGS. 4 to 10 show, by way of example, the flexible possibility of locating the co-molded inserts 5 , where the precision of the positioning with respect to the edges of the molded product 7 can be immediately seen. | A molding system with inserts placed on the die and/or the punch of the mold, which allows one to obtain molded products with co-molded ferromagnetic inserts on the surfaces thereof. | 1 |
BACKGROUND OF THE INVENTION
U.S. Pat. No. 4,123,213, Laramore, discloses a vacuum system for dusting floor to allied bakery products as they are being transferred from a dough dividing and rounding machine to an aging and panning machine.
The present invention relates to a broadly similar dusting flour recycling system which constitutes an improvement on the prior patented system, in terms of increased efficiency of operation, greater versatility of usage and increased economies resulting from the use of the invention in high production bakery facilities, such as those producing hamburger and hot dog rolls, and the like.
More particularly, the advantages derived from the installation and operation of the dusting flour recycling system according to the present invention include, among others:
(1) Reclaims a greater quantity of clean reusable flour, up to approximately 13 pounds per hour for a single installation of the system.
(2) The virtual elimination of unhealthy flour dust from the air of the commercial bakery in which the invention is installed and used.
(3) Greatly improved sanitation throughout the bakery in contrast to heavy contamination of exposed surfaces with flour when no recycling system is used.
(4) Major reduction in labor costs for clean-up operations, and much less frequent cleaning of premises required.
(5) System has the capability of eliminating dusting flour on the bottom surface of the finished product as well as on all other exposed surfaces.
(6) The use of the system greatly extends the life of the baking pan glaze by preventing contamination of the glaze with flour, later to become baked on the pans.
(7) System thoroughly filters the reclaimed flour, making it ready for reuse in the dusting of bakery products.
(8) The vacuum system can be located remotely (80 feet or more) from the product line without the flour settling out in the pipe connecting the vacuum system with the head which spans the top of the sheeted product conveyor line.
SUMMARY OF THE INVENTION
A flour recycling system includes a compressed air and vacuum head placed over a sheeted bakery product conveyor line immediately downstream from sheeting rollers which act on aged dough balls as they are discharged from the aging and panning machine or "Panomat". In the compressed air and vacuum head, the sheeted dough pieces are cleansed of flour on all surfaces including their bottoms. The flour removed from the dough pieces along with any dough particles is conveyed through a hose of any required length up to 80 feet or more to the inlet of a dual section separator in which the flour and any entrained dough particles and debris are subjected to a two-stage vacuum induced centrifugal action. In the second stage, the cleansed flour is drawn by vacuum through fine mesh screens while the removed dough particles and debris settle by gravity in the first stage separation chamber from which they can be removed at proper intervals.
The cleansed flour, after traversing the screens, is forced into two upright axis reclaimed flour tanks, each containing a vortex eliminator through which the incoming flour must pass when entering the tank. Each tank is topped by a fabric air release bag. Each tank includes a lower tapered outlet section mounting a vibrator and leading to an elongated flour outlet chute or sock through which recycled flour is delivered at proper times into receiver containers placed beneath the tanks without the escape of flour dust into the surrounding atmosphere.
A very unique feature of the system is its ability to self clean the air release bags and reclaimed flour tanks cyclically without shutting down the system. This cleaning can be accomplished under manual control or by the operation of an automatic timer. When done manually, the on-off switch for the blower of one tank is turned off during the emptying of that tank and the blower of the other tank is allowed to remain running. This enables a thorough vacuum cleaning of the air release bag, tank and flour discharge sleeve, while the flour recycling system continues to operate with relatively little loss of efficiency. The blower associated with one tank and its air release bag causes the vacuum cleaning of the other tank and its air release bag while continuing to recycle flour.
The vacuum cleaning can be carried out in an automatic mode by a conventional automatic timer which can alternately turn off the blowers approximately every ten minutes, for a period of fifteen to twenty seconds, by operating the on-off switches of the blowers. The same beneficial results are obtained with automatic or manual control of the blower on-off switches, although automatic timer operation is preferred. In either case, the last remaining flour dust in the tank whose blower is inactive is sucked through the filter screen of the tank whose blower is in operation and into the reclaimed flour tank associated with that blower. In essence, therefore, the system is self-cleaning without the necessity of being totally shut down and without allowing the escape of flour dust into the surrounding atmosphere.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of a dusting flour recycling system according to the present invention.
FIG. 2 is an elevational view of the system taken at right angles to FIG. 1.
FIG. 3 is a perspective view of a unitized dual flour recycling tank, separating and vacuum induction assembly mounted on a mobile support stand.
FIG. 4 is a perspective view showing the dual stage separator and filter screen portion of the system.
FIG. 5 is a further perspective view, particularly showing the first stage separator.
FIG. 6 is a plan view of the product line compressed air and vacuum head.
FIG. 7 is a side elevation of the same.
FIG. 8 is an end elevation of the compressed air and vacuum head.
DETAILED DESCRIPTION
Referring to the drawings in detail wherein like numerals designate like parts, dough balls 20 are discharged in succession from a "Panomat" aging and panning machine 21 having a multiplicity of dough ball conveyor cups 22. From the "Panomat" 21, the aged dough balls 20 pass downwardly through a chute structure 23 to sheeting rollers 24 which form the dough balls into flat relatively thin dough pieces 25. The sheeted dough pieces 25 move down a steeply inclined apron 24a and onto the top run of a horizontal conveyor 26 beneath which baking pans 26a for hamburger buns or the like are being conveyed horizontally. The pans 26a have a release coating or glaze in accordance with conventional practice. At the downstream end of the conveyor 26, the dough pieces 25 slide down another apron 26b and into pockets provided in the baking pans 26a. The movement of the pans 26a is controlled in a stop and go mode by a conventional oscillating pawl mechanism 26c. All of the apparatus thus far described is conventional and need not be discussed in greater detail.
When the dough balls are delivered to the upstream end of the "Panomat" 21 from a standard dough dividing and forming machine, not shown, a large amount of dusting flour is applied to product, as described in U.S. Pat. No. 4,123,213. Much dusting flour remains on the dough balls 20 as they leave the discharge end of the "Panomat" 21, FIG. 1, and pass through the sheeting rollers 24 and onto the conveyor 26. It is the purpose of the flour recycling system according to the present invention, about to be described, to remove substantially all flour from the dough pieces 25 and deliver this flour in a cleansed and sifted state to receptacles from which the reclaimed flour can be reused as dusting flour or for making additional dough, as need dictates.
The flour recycling system comprises a compressed air and vacuum head 27 disposed immediately above the conveyor belt 26 and spanning the entire width of the belt on which the dough pieces 25 are being transported. The head 27 comprises a hood-like body portion 28 including corner legs 29 which straddle the conveyor belt 26 and rest on the solid surface. Side openings 30 are provided in the hood 28 between the legs 29 for the admission of clean ambient air into the hood. The top wall of the hood carries a central vacuum hose connector sleeve 31 rising therefrom as shown.
A compressed air pipe 32 having two spaced parallel branches 33 is arranged as a continuous horizontal loop across the head 27, FIG. 6. The pipe branches 33 are arranged near and inwardly of the upstream and downstream end of the head 27 and are at an elevation somewhat above the outside air inlet openings 30. The pipe branches 33 have spaced apertures 34 along their lengths with their axes converging downwardly to direct multiple stream 35 of compressed air downward at angles to the conveyor belt 26, as shown graphically in FIG. 8. These compressed air streams 35 actually lift the dough pieces 25 slightly from the belt 26 with a dancing action and clean all flour from the bottoms of the dough pieces during their passage through the head 27.
Vertical baffle plates 36 having inclined lower extensions 37 are positioned in the opposite sides of the head 27 to form vertical passages 38 for incoming clean ambient air whose direction of flow is indicated by the lines 39, FIG. 7. The inclined baffle extensions 37 serve to direct compressed air coming from the apertures 34 inwardly at the opposite sides of the head 27, as shown by the directional arrows 40. The baffle extensions 37 also provide passages above the conveyor belt 26 for the admission of fresh air to further suppress dust, as shown in FIG. 7. The vacuum created inside of the head 27 by the means now to be described effectively removes flour from all of the other surfaces of the dough pieces 25 during their passage through the head 27 on the belt 26.
The sleeve 31 is connected through a flexible vacuum hose 41 with a vacuum assembly 42. As best shown in FIG. 3, the unitized assembly 42 can be supported on a wheeled stand 43 for mobility. In practice, the hose 41 can be 80 feet or more in length with no settling out of flour in the hose between the compressed air and suction head 27 and the vacuum assembly 42. It is frequently convenient to locate the assembly 42 remotely from the head 27. However, in some instances, the vacuum assembly 42 can be located relatively near and above the head 27 and conveyor 26, in which case a short vacuum hose 41 is used.
In any case, the end of the hose away from the head 27 is connected to an inlet elbow 44 of a dual stage separator 45 including a first or lower separator stage 46 and a perpendicular axis second or upper stage separator section 47. The first separator stage 46 has a vertical axis and the second stage 47 has a horizontal axis. The two separator stages are in communication through a rectangular sleeve 48 connected into a cylindrical sleeve 49 inside of the first stage housing 46. The lower end of the internal sleeve 49 terminates somewhat above the bottom of the first stage housing 46, FIG. 5. The first stage housing 46 of the separator is equipped with a drop bottom 50 having a retaining latch 51. This arrangement enables periodic dumping of dough particles or other debris which accumulates in the first or lower stage of the dual stage separator 45.
It can be noted that the inlet elbow 44 connects into the lower vertical axis separator stage 46 tangentially through another elbow 52. Similarly, the sleeve 48 connects into the upper horizontal axis separator stage tangentially. Consequently, flour and dough particles drawn through the hose 41 by vacuum from the head 27 are subjected to a first stage centrifugal separating action in the housing 46 around the sleeve 49, and after passing upwardly through the sleeve 49 and rectangular sleeve 48 are subjected to a second stage centrifugal separating action in the housing 47. As a result of the two stages of centrifugal separation, all dough particles or other debris will settle out on the drop bottom 50 for easy emptying and only flour will be elevated into the second stage housing 48 of the separator assembly 45.
Two coaxial horizontal delivery pipes 53 lead from the two vertical end walls of second stage housing 47 and are coupled as at 54 with two independently operable blowers 55, each having an on-off control switch. Within the housing 47 in spaced opposed relationship, the ends of pipes 53 are covered by fine sifting screens 56, preferably 30 mesh screens. Only fine flour of the type suitable for reusing can pass through the screens 56, and all other material will be rejected and will either fall onto the drop bottom 50 or accumulate in the upper housing 47. The upper housing 47 is equipped with a hinged sealed access door 57 having a transparent window 58 through which the two screens 56 may be viewed.
After being drawn by vacuum created by the two blowers 55 through the screens 56, the cleansed flour passes through tangential flour outlets 59 and through coaxial inlet pipes 60 which extend inside of two upright axis flour recycling tanks 61. The inlet pipes 60 connect into vortex eliminators 62 inside of each tank 61, above tapered lower discharge extensions 63 of the tanks. Flour being forced into each tank 61 by one of the blowers 55 must enter the tank through a vortex eliminator 62.
Each tank is equipped at its top with a fabric air release bag 64 through which only clean air is discharged into the surrounding atmosphere.
Each outlet extension 63 has mounted thereon a mechanical vibrator 65 to cause flour to discharge downwardly from each tank 61 and into a suitable collection receptacle 66 below the tank.
To facilitate this discharge of reclaimed flour from the tanks 61, each tapered outlet 63 is equipped at its bottom with an elongated fabric sleeve or sock 67 adapted to be tied off at any elevation by an adjustable tie 68. A long extension 69 of each sleeve 67 is held elevated by a retainer loop 70 on each sleeve 67 near its top. When it is desired to release the flour from each tank 61 for passage through the sleeve 67 to the receptacle 66, the tie 68 is released and the extension 69 is separated from the retainer loop 70 and lowered into the top of the receptacle 66 whereupon flour can pass into the receptacle without creating a cloud of flour dust in the surrounding atmosphere. The blower 55 of the tank being emptied through the sleeve 67 is turned off during the emptying process.
A very unique feature of the flour recycling system resides in its self-cleaning ability without necessitating shut down of the system. This is accomplished in the following manner. Normally, in the operation of the system, both blowers 55 are operating, and flour, plus any dough particles present, are pulled by suction from the head 27 and through both dual stage separators 45 and vortex eliminators 62 into the tanks 61. However, after a certain time of operation, the tanks and their air release bags 64 require cleaning. To accomplish this, as previously explained, the blower 55 for the tank and bag requiring cleaning is shut down through its on-off switch and the other blower 55 of the system remains in operation. This can be accomplished manually or by means of an automatic timer, as previously described.
When done manually, the blower 55 is turned off through its on-off switch for one tank 61 during the emptying of such tank into the receptacle 66, and at no other time. With the blower of the other tank not undergoing emptying in full operation, the last remaining flour dust in the tank being emptied and in its air release bag 64 will be vacuumed through the screens 56 and through the active blower 55 and into the tank 61 connected therewith. This vacuum cleaning operation is accomplished without releasing flour dust into the atmosphere, because the vacuum is effective even near the bottom of the sleeve 67 and receptacle 66 for the tank being vacuum cleaned.
The air release bag 64 of the tank being vacuum cleaned will collapse onto a support frame 71 provided in the air release bag, and this frame will prevent the flexible bag from turning inside out during the vacuum cleaning process. The cleaning process also effectively cleans the sifting screen 56 of the tank whose blower 55 has been shut down.
When the on-off switches of the blowers 55 are being operated alternately by an automatic timer as described previously the vacuum cleaning mode of operation will be the same in essence as it is under manual operation of the blower on-off switches. About every ten minutes, under timer control, which is preferred over manual control, each blower will be turned off for a ten to fifteen second interval to permit vacuum cleaning of the associated tank and air relese bag. At this time, the other blower of the system remains in operation. After the approximate ten minute period, the other blower is turned off automatically by the timer and the blower first turned off by the timer is automatically restarted.
Thus, with either manual or automatic control of the two blowers 55 through their on-off switches, the tanks 61 and their air release bags are alternately vacuum cleaned without shutting down the recycling system. The system can still operate with good efficiency while only one blower 55 is running and the other one is shut down for vacuum cleaning, as described. The arrangement maintains the bags 64 in a clean state which is necessary for efficient operation of the system.
It can be seen that the previously-stated advantages of the invention are fully realized in an economical manner by the operation of a relatively simple apparatus. Large amounts of costly flour are reclaimed for subsequent use while a heathful atmosphere is being maintained for workers. Exposed machinery surfaces are kept clean, resulting in improved sanitation.
It should be noted that the blowers 55 create vacuum in the head 27, hose 41, dual stage separator 45 and pipes 53 connected with the blowers. However, simultaneously, the blowers 55 deliver clean sifted flour through the vortex eliminators 62 into the tanks 61 under positive pressure.
It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of the invention or scope of the subjoined claims. | A flour recycling system includes a compressed air and vacuum head placed over a bakery product conveyor line. Flour is removed from the product units and is conveyed through a vacuum hose to the inlet of a remotely located dual stage separator in which the flour with entrained dough particles is subjected to a two-stage vacuum induced centrifugal separating process. Cleansed flour is drawn by vacuum through two fine mesh sifter screens into two reclaimed flour tanks each containing a vortex eliminator and each having an air release bag. Reclaimed flour is delivered to storage receptacles beneath the tanks through elongated flexible chutes which can be tied off and closed at desired elevations. The tanks, their air release bags and flexible chutes can be individually vacuum cleaned without shutting down the system merely by stopping the operation of one blower while continuing to operate the other blower of the dual blower system, one for each tank. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to a speed controller for motor vehicles.
BACKGROUND INFORMATION
[0002] German Published Patent Application No. 199 58 120 refers to a speed controller that is operable in a so-called ACC mode (adaptive cruise control), and in a stop and go mode.
[0003] In the ACC mode, the speed of the vehicle is regulated to a desired speed selected by the driver, provided the roadway ahead of his own vehicle is clear. A distance gap sensor, such as a radar sensor, permits detecting vehicles traveling ahead on his own traffic lane and other obstacles, and adjusting speed, if necessary, in such a way that the immediately preceding vehicle is followed at an appropriate safety distance. The ACC mode is provided, in general, for travel on express highways or well developed highways having flowing traffic, and also for traffic situations characterized by relatively low dynamics and relatively large vehicle separations. Under these conditions, a long-range tracking radar, having comparatively low depth resolution, is sufficient for recording the traffic surroundings. The relative speed of the tracked object is directly measurable with the aid of the Doppler effect. In order to avoid frequent faulty reactions of the system, only moving radar objects are generally considered as relevant target objects, since, in general, it is not to be expected that there are standing objects on the roadway. However, in traffic situations having greater dynamics, such as in slow-moving traffic or stop and go traffic, or even in city traffic, standing targets should also be included in the evaluation. Moreover, in this case, because of the generally shorter vehicle separations, a more detailed detection and evaluation of the traffic situation is also desirable. The ACC mode is unsuitable for these traffic situations and is therefore only able to be activated when the speed of one's own vehicle is above a certain limiting speed, such as above 30 km/h.
[0004] Alternatively, the stop and go mode is provided for the lower speed range and affords functions that are not available in the ACC mode, in particular the function of braking one's own vehicle to a standstill, such as when driving upon a traffic jam. Under certain circumstances an automatic restart-up is then also possible, when the preceding vehicle is also set in motion again. These conditions are satisfied, for example, when one's own vehicle has stood still for a relatively short time, and when the target object followed up to the present, that is, the preceding vehicle, has constantly remained in the tracking range of the distance sensor. On the other hand, under other conditions, it may be expedient to deactivate the system altogether, or simply to have it emit a start-up prompt to the driver when the preceding vehicle starts up, and to leave the last decision up to him. For an expanded functionality in the stop and go mode, not only is the detection of standing targets required, but in general an additional close-range sensor system is also desirable, such as in the form of a video system having electronic image evaluation, a close-range radar or a light-optical distance sensor for the close range including the left and right roadway edges, so that suddenly-appearing obstacles may also be detected in time. This more complex detection and evaluation of the traffic environment, which may be required in the stop and go mode, can lead, at high speeds, to faulty reactions or to an overload of the system. For this reason, the stop and go mode is typically only activatable at speeds up to an upper limiting speed, such as up to 40 km/h.
[0005] In the overlapping zone between the speed ranges for ACC and Stop and Go modes, that is, in the exemplary systems described, between 30 and 40 km/h, both modes can be activated and the selection of the mode is left to the driver. Special mode selection keys are provided in the known system for selecting the operating mode, using which, the driver is able to activate either the ACC mode or the Stop & Go mode. The active participation of the driver in the selection of the operating mode is regarded as efficacious, because in this way it is made clear to the driver in which mode the system happens to be, and which functions of the speed controller are available. Thus, if the preceding vehicle suddenly stops, and the driver mistakenly assumes that the speed controller is in the Stop & Go mode and relies on the speed controller automatic braking to a standstill may be prevented. However, some drivers feel that the necessity of having to select the operating modes themselves is an impairment of their operating convenience, and that the command keys needed for this purpose make the operating system more involved and complex.
SUMMARY OF THE INVENTION
[0006] The speed controller according to the present invention may have the advantage of greater operating convenience, clarity and plausibility of the operating system when consideration is given to safety aspects.
[0007] According to an exemplary embodiment of the present invention, the speed controller simultaneously interprets commands that allow the driver to increase or decrease the desired speed as commands for changing the operating mode under appropriate conditions. Consequently, special command keys for the selection of the operating mode may be omitted. The driver remains a participant in the selection of the mode, by way of the input of the desired speed, so that the transparency of the system remains observable to the driver. A mode change, which is connected not to a restriction, but rather to a broadening of the scope of the functions of the speed controller, does not require any increased attention of the driver, and can therefore also be introduced automatically, without participation of the driver. If, on the other hand, the mode change has the effect of making a safety-relevant function no longer available, then the driver should be made aware of this so that he does not mistakenly rely on this function. However, if the driver actively selects a speed which is clearly outside the speed range permitted for the current mode, then it will be clear to the driver that the current mode cannot be maintained, and therefore the selection of this desired speed indicates that the driver consciously wants to assume a greater responsibility, so that the input of an additional command to change the operating mode is unnecessary.
[0008] In order to increase transparency, the driver may be made aware by a suitable signal, such as an optical or an acoustical signal, that a mode change has taken place, and in which mode the speed controller currently is to be found.
[0009] In one embodiment, the speed controller has only two main operating modes, namely an ACC mode and a mode designated here as “Stop & Roll”. The concept “Stop & Roll” refers to a mode which lies somewhere between the ACC mode and the Stop & Go mode, discussed above, with respect to the sensor system required and the complexity in the evaluation of the traffic environment. In the Stop & Roll mode, as in the Stop & Go mode, automatic braking of the vehicle to a standstill is possible, but, because of the restricted sensor technology, this mode is not intended for highly dynamic traffic situations such as occur, for instance, in city traffic.
[0010] In order to avoid frequent mode changes, the changeover as a function of the desired speed selected by the driver may take place with a certain hysteresis. Thereby, the speed controller may remain in the current mode if the desired speed selected lies within the overlap range in which both operating modes are permitted.
[0011] Since the actual speed of the vehicle does not always correspond to the desired speed set by the driver, the actual speed of the vehicle should also be drawn upon as a criterion for a mode change. In this case, the actual speed may be regarded as the speed indicated to the driver on the tachometer. It is believed that it also may be advantageous if the criterion “actual speed” is also handled flexibly, in the sense that short-lived undershooting of the Stop & Roll switchover speed may be tolerated with the aid of a timer. Thus, the driver has the opportunity to input a higher desired speed prospectively in the Stop & Roll operation, and thereby (implicitly) to give the command to change into ACC mode, when it is recognized that traffic is decreasing. Normally, the vehicle will then accelerate within a short time to a speed at which ACC operation is permissible. When the minimum speed for ACC is not reached within a threshold time span such as 5 seconds, the system may automatically relapse into Stop & Roll mode again.
[0012] If the desired speed that is set is greater than the limiting speed for ACC, but the actual speed of the vehicle falls below this value on account of the traffic, and remains below this value for a certain time, a switchover may automatically take place into the Stop & Roll mode. In this case, the desired speed is limited automatically to the greatest value permissible for Stop & Roll. Then, to return into the ACC mode, a driver-initiated action may be required, such as the input of a higher desired speed.
[0013] In both main operation modes an override by operating the gas pedal is possible. The acceleration request input by the driver on the gas pedal then has precedence over a lower setpoint acceleration calculated by the speed controller. Even in these override situations, a change between the two main modes is possible, but a change from Stop & Roll to ACC mode may be permitted only when the driver actively raises the desired speed. Otherwise, the speed controller may be deactivated if the actual speed reaches a threshold value, at which the functions of the Stop & Roll operation are no longer maintained.
[0014] When the speed controller has been deactivated, it can be reactivated by the input of a desired speed. A decision may follow as to which of the ACC mode or the Stop & Roll mode is to be activated, as a function of whether the actual speed lies above or below the limiting speed for ACC.
[0015] In one exemplary embodiment, the decision regarding a mode change and/or regarding the activation or deactivation of an operating mode can also be a function of whether certain conditions with respect to the recording of the traffic environment are satisfied, so that an ever greater operating safety is achieved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 shows a block diagram of a speed controller according to an exemplary embodiment of the present invention.
[0017] FIG. 2 shows a diagram of exemplary speed ranges at which the various operating modes of the speed controller may be activated.
[0018] FIG. 3 shows a diagram depicting exemplary transitions between the various main operating modes and associated conditions of the speed controller.
DETAILED DESCRIPTION
[0019] FIG. 1 shows a speed controller 10 by which the speed of a motor vehicle is controlled to a desired speed selected by the driver. To operate speed controller 10 , a multifunctional lever may be provided on the steering wheel, which fulfills the functions of several function keys, which may include: a “+” key 12 to activate the control and for raising the desired speed V set , for example, in steps of 10 km/h; a “−” key 14 for activating the controller and for reducing desired speed V set ; an OFF key 16 for deactivating the controller and a resume key 18 for renewed activation of the controller and setting the desired speed prevailing before the last deactivation. In response to the first activation of the controller with the aid of the “+” key or “−” key, the actual speed V of the vehicle rounded up or down in tens (e.g., 30, 40, 50) can be taken to be the desired speed V set of the vehicle, just as it is displayed on the tachometer. When resume key 18 is pressed, without a desired speed having been stored, for the determination of the desired speed there is a rounding to the whole ten that is closest to the actual speed.
[0020] Speed controller 10 receives signals from a long range distance sensor 20 , such as a long range radar and from a short range sensor system 22 , which is formed, for example, by a short range radar, a light-optical distance sensor system, a video system and the like. When the sensor system detects a preceding vehicle traveling in one's own lane, the speed of the vehicle may be reduced to below the set desired speed, so that the preceding vehicle may be followed at an appropriate safety distance, for example, at a selectable time gap of 1 to 2 seconds. In an ACC operating mode, the spacing regulation takes place exclusively with the aid of signals of long range distance sensor 20 , which has a locating range such as 10 to 200 m. This operating mode is provided for travel on express highways and highways for traffic situations in which, in general, people travel at relatively high speeds. In addition, speed controller 10 has a controller mode which is designated as Stop & Roll and is provided for traffic situations having high traffic density and correspondingly low speed, such as for slow-moving traffic or traffic jam operation on express highways and highways. In this mode, signals of the short range sensor system 22 are also evaluated, so that shorter vehicle spacing may be detected more accurately. Whereas in the ACC mode only movable objects are considered as relevant target objects, in the Stop & Roll mode other standing targets that are detected by long range distance sensor 20 or by close range sensor system 22 are also evaluated. In addition, close range sensor system 22 also has a greater locating angular range, so that objects which are located in close range on neighboring lanes or at the edge of the roadway can also be detected. In this manner, the system enables reactions in time to suddenly appearing obstacles, such as vehicles suddenly swinging in from the side lane.
[0021] The Stop & Roll mode has at least one controlling function which is not available in the ACC mode, in particular, a stop function by which the vehicle may be automatically braked to a standstill upon approaching a standing obstacle.
[0022] The control functions in the two operating modes ACC and Stop & Roll are known to those of ordinary skill in the art, and are therefore not described here in greater detail.
[0023] Speed controller 10 has a decision unit 24 which, in dependence upon the respective traffic situation and with the collaboration of the driver, determines in which operating mode the speed controller is working. The criteria for these determinations is explained in more detail below. Speed controller 24 also includes one or more integrated timers 26 , which are used in the connection with the determination processes.
[0024] If decision unit 24 has selected the ACC mode, this is indicated to the driver by the lighting up of an indicator light 28 on the dashboard. Correspondingly, an indicator light 30 indicates the operating mode Stop & Roll. In addition, a loudspeaker 32 is provided, via which the driver is made aware of a change in the operating mode by an acoustical signal, or may even be warned of certain system states or traffic situations.
[0025] In FIG. 2 , exemplary speed ranges are shown, in which the operating modes ACC and Stop & Roll (S&R) may be activated. As shown, the ACC mode can be activated when the actual speed V of the vehicle is greater than a limiting speed V s . The S&R mode can be activated when the actual speed of the vehicle is lower than a speed V s +h 1 . The speed range between V s and V s +h 1 is consequently a hysteresis range, in which either the ACC mode or the S&R mode may be active. As an example, let us assume that the limiting speed V s is 30 km/h and that the hysteresis interval h 1 is 5 km/h.
[0026] FIG. 3 shows the various operating states of the speed controller as well as significant transitions between the operating states. The active operating states are divided into the main operating modes ACC and S&R.
[0027] In a state 32 referred to as “readiness”, the sensor systems and the evaluation and control algorithms of speed controller 10 are active, so that the traffic events can be followed, but no control commands are given to the driving or the braking system of the vehicle and control over the vehicle remains with the driver. So long as the driver does not actively input a command to activate the speed controller, the speed controller remains in the readiness state, as is symbolized by an arrow T 1 .
[0028] The driver can activate the speed controller by operating “+” key 12 , “−” key 14 or resume key 18 . Decision unit 24 then determines, in the light of the present actual speed V, whether the speed controller is changing into state 34 “ACC active” or state 36 “S&R active”. If actual speed V is greater than limiting speed V s , then, upon the activation of each of the three keys 12 , 14 , 18 , transition into state 34 “ACC active” corresponding to arrow T 2 in FIG. 3 takes place. If, on the other hand, actual speed V is less than or equal to V s , transition into state 36 “S&R active” takes place according to arrow T 3 . In this case, the desired speed is set to V s , provided that the desired speed set by operating keys 12 , 14 and 18 is greater than this value. As a result, the ACC mode can be activated only when the speed of the vehicle is at least 30 km/h. Otherwise, the controller goes into S&R mode, and the vehicle speed is limited to the range of 1 to 30 km/h, that is, to the range in which a flawless functioning of the S&R mode is ensured.
[0029] In state 36 , the driver has two possibilities of accelerating the vehicle to above 30 km/h and of going over into ACC mode. Firstly, the driver can select a greater desired speed by single or multiple operation of “+” key 12 . As soon as the new desired speed V set is greater than V s +h 1 , that is, at least 40 km/h, decision unit 24 causes a transition into state 34 , as shown by arrow T 4 . Alternatively, the driver may operate the gas pedal in state 36 , and thus override the S&R control function, so that, according to arrow T 5 , the controller goes over into state 38 , “override S&R”. After the vehicle has been accelerated to the desired speed, and the driver lets up the gas pedal, the controller returns to state 36 “S&R active”, according to arrow T 6 . If a desired speed V set is then selected by operating “+” key 12 or “−” key 14 , that is greater than V s +h 1 , the controller goes to state 34 via arrow T 4 . The driver may also be able to select a desired speed V set that is greater than V s +h 1 , even while he holds down the gas pedal and thus is in state 38 , by operating the “+” key or the “−” key. Then, as soon as the actual speed V is greater than V s +h 1 , there is a transition to state 40 “override ACC”, according to arrow T 7 . If the driver now lets up the gas pedal, according to arrow T 8 , transition takes place into state 34 “ACC active”. The speed of the vehicle is then controlled to the newly selected desired speed V set , and the actual speed will also remain above 30 km/h, since the speed was at least 35 km/h when the gas pedal was let up.
[0030] As can be discerned from the description above, the driver operates at least once “+” key 12 or “−” key 14 (or resume keyl 8 ), to reach the ACC mode (state 34 ) from the S&R mode (state 36 ). As a result, this mode change does not take place without the active participation of the driver, and consequently does not occur against the will of the driver.
[0031] The driver may override state 34 “ACC active” by operating the gas pedal, so that he temporarily reaches state 40 , according to arrow T 9 .
[0032] Arrow T 10 in FIG. 3 describes the regular transition from ACC mode into S&R mode, or, more accurately, the transition from state 34 into state 36 . This transition is possible when one of the following conditions is satisfied:
a) The desired speed V set is lower than limiting speed V s , and in addition, the actual speed V is lower than V s +h 1 . This corresponds to the situation in which the driver selects a low desired speed by operating “−” key 14 . The vehicle will then slow down, and the transition into S&R mode takes place as soon as the speed range provided for this mode is reached, according to FIG. 2 . b) Actual speed V decreases from a value above limiting speed VS to a value below this limiting speed. This is typically the case when, upon driving up to the end of a traffic congestion, long-range distance sensor 20 detects a slow or stopped vehicle in its own lane, and accordingly throttles the speed. The transition into the S&R mode then takes place as soon as the speed region permissible for the ACC mode is exited. In this case, the desired speed V set is automatically set to V s in order to ensure that the speed controller, when the congestion has lifted, does not return again by itself to the ACC mode, but only occurs when the driver actively raises the desired speed again, corresponding to a transition according to arrow T 4 . The transition from ACC to S&R may also be restricted to take place when V s is undershot for the duration of a certain time interval. This achieves a certain tolerance against noise in the speed signal. c) desired speed V set is raised by driver command to a value which is greater than V s +h 1 , and, in addition, after the expiration of a time span measured by timer 26 , actual speed V is still lower than V s . This corresponds to the situation in which the driver, according to arrow T 4 , wishes to change into ACC mode, but the limiting speed V s that is required for this mode cannot be achieved within an appropriate time span such as 5 seconds, for instance, because there is a slower preceding vehicle in front of the driver's vehicle. In this case, the speed controller automatically returns to state 36 again, after the expiration of the time span mentioned. In order to reach state 34 , the driver must then once again input a command to increase the desired speed as soon as the lane ahead of him is free.
[0036] In exceptional cases, a transition from state 40 “override ACC” into state 38 “override S&R” is also possible, as indicated by arrow T 11 . This transition takes place when the driver lowers the desired speed to a value below V s , and the actual speed V decreases to below V s in spite of the operation of the gas pedal, i.e. when the driver decreases the desired speed, but then, by operating the gas pedal, assures that the vehicle decelerates slower than is specified by the speed controller.
[0037] From state 36 “S&R active” a transition into a state 42 “S&R stop” is also possible, as symbolized by arrow T 12 . In state 42 , speed controller 10 causes the automatic braking of the vehicle to a standstill. Subsequently, the speed controller, according to arrow T 13 , goes over into one of several start-up states which determine whether the renewed starting up of the vehicle is controlled by speed controller 10 , if traffic conditions permit it, or when the driver confirms a corresponding start-up request, or whether the start-up procedure is controlled by the driver himself. Details of these start-up procedures are described in German Published Patent Application No. 199 58 520.
[0038] The transition into state 42 according to arrow T 12 takes place when, in state 36 , the speed of the vehicle (the determining factor here is not the indicated but the actually measured speed) has decreased to below a threshold value such as 4 km/h, e.g., when approaching a standing obstacle. Since this function “braking to a standstill” is only available in the S&R mode, in the speed controller described here, the transition from the S&R mode into the ACC mode, and thus the renouncement of this function, is only permitted when the driver inputs a corresponding command by active operation of one of keys 12 , 14 or 18 .
[0039] In each of the active states, speed controller 10 can be inactivated if one of several predefined events occurs. The most important of these events are the operation of OFF key 16 by the driver and the operation of the brake pedal by the driver. In FIG. 3 , deactivation from state 36 “S&R active” is shown by an arrow T 14 . The speed controller then runs through a transition state 44 , in which the control commands given out to the drive and/or brake system are gradually driven back, so that a jerk-free transition and a correspondingly great riding comfort is achieved. From transition state 44 , the speed controller then goes into state 32 “readiness” again, according to arrow T 15 . The desired speed prevailing before the deactivation remains stored, however, and is called up again when the driver operates resume key 18 in state 32 . An exception may optionally be provided for the case in which the stored desired speed is greater than limiting speed V s , and at operation of resume key 18 the actual speed of the vehicle is less than V s . In that case there is then a transition into S&R mode, and the desired speed is set to V s , as was described in connection with arrow T 3 . This takes into account the possibility that the driver, after a protracted inactive phase of the speed controller, has forgotten that he was last in ACC mode, in which the function “brake to standstill” is not available.
[0040] As was described in connection with arrow T 7 , a transition from state 38 “override S&R” into state 40 “override ACC” takes place only when the driver increases the desired speed which was prevalent up to now in the S&R mode. If the desired speed remains unchanged, and the driver accelerates by operating the gas pedal, it can therefore happen that the speed becomes greater than the speed permissible for the Stop & Roll mode. In this case the speed controller is compulsorily deactivated, as is symbolized by arrow T 16 . This deactivation takes place under condition that desired speed V set is less than or equal to V s , and that, in addition, actual speed V is greater than a threshold value V s +h 2 . Here h 2 is a hysteresis parameter which may be the same as h 1 .
[0041] In FIG. 3 , still two further states 46 “ACC braking” and 48 “S&R braking” are shown, in which the speed controller can only act upon the braking system of the vehicle, but not upon the drive system. These states are reached when the parking brake is operated in the ACC mode (state 34 ) or in the S&R mode (state 36 ), or when in these modes the electronic stability program (ESP) of the vehicle detects a lane condition having low frictional connection (e.g. an icy road). A transition is in that case only possible in the direction from an ACC mode into the S&R mode, that is from state 46 into state 48 , according to arrow T 17 , when the actual speed V is lower than V s . From state 48 braking to a standstill is possible again (via arrow T 18 ).
[0042] Whereas in the exemplary embodiment described here the desired speed can only be changed in intervals of 10 km/h, this was for illustrative purposes only and the desired speed may also be changed gradually or in smaller increments, such as at intervals of 1 km/h.
[0043] The conditions for the change between modes ACC and S&R are summarized once more in the following Table 1.
TABLE 1 Activation ACC T2 V > Vs AND (+, − OR resume operated) Activation S&R T3 V ≦ Vs AND (+, − OR resume operated) (V set is limited to V s ) S&R after ACC T4 V set > V s + h 1 T7 V set > V s + h 1 AND V > V s + h 1 ACC after S&R T10 (V set < Vs AND V < V s + h 1 ) OR (V decreases below Vs) OR (V set > V s + h 1 AND V < V s AND timer expired) T11 V set < V s AND V < V s Deactivation S&R T16 V set ≦ V s AND V > V s + h 2
[0044] In a second exemplary embodiment of the speed controller, other conditions may apply to the transitions between the states shown in FIG. 3 . For the definition of these conditions, parameters are used which are stored in decision unit 24 , and which are specified as follows:
[0045] Threshold value for the switchover between ACC and S&R
V select =35 km/h
[0046] Maximum desired speed for S&R:
V SRset =30 km/h.
Minimum speed (limiting speed) for ACC:
V ACCmin =30 km/h
[0048] Threshold value for devaluating S&R when overriding
V SRs =45 km/h
[0049] Maximum vehicle distance for activating S&R:
d SRon =30 m
[0050] Maximum vehicle distance for deactivating S&R:
d SRoff =50 m
[0051] Waiting time when target object is lost:
T 1 =5 s
[0052] The conditions for activating and deactivating the operating modes ACC and A&R, and for the change of mode are listed in the following Table 2.
TABLE 2 Activation ACC T2 V > V select AND (+ OR − operated OR (resume operated AND V set (slt) > V s )) Activation S&R T3 V = V select AND (+, − OR resume operated) AND d < d SRon (is limited to V SRset ) S&R after ACC T4 V > V select AND V set > V select T7 V SRs ≧ V > V select AND V set > V select ACC after S&R T10 V decreases to under V ACCmin Deactivation S&R T14 t > T1 OR d > d SRoff OR (V > V SRs AND (none of keys +, − OR resume is operated)) T16 V > V SRs AND (none of keys +, − OR resume is operated)
[0053] The ACC mode is activated (arrow T 2 ) when actual speed V is greater than limiting speed V select , and, in addition, the driver operates “+” key 12 or the “−” key. The operation of resume key 18 , by which the last stored desired speed is reestablished, only effects the activation of the ACC mode if the last stored desired speed V set(alt) is greater than V select .
[0054] Mode S&R is activated (arrow T 3 ) when actual speed V is at most equal to V select , and the driver operates a key 12 , 14 or 18 .
[0055] However, in addition, in this exemplary embodiment the condition that the sensor system has detected a target object, and the distance of the target object is at most equal to d SRon , that is, at most 30 m must also be satisfied. As a result, the Stop & Roll can only be activated when a target object, such as a vehicle traveling ahead, is available at a distance that is not too great so that the actions of the speed controller are determined by the behavior of the preceding vehicle. By this, faulty reactions are avoided that come about when a relevant target object has not been recognized by the distance sensor system.
[0056] Upon activation of the S&R mode, desired speed V set is limited in this example to speed V SRset (30 km/h).
[0057] A change from state 36 “S&R active” into state 34 “ACC active” according to arrow T 4 , occurs in this exemplary embodiment when actual speed V is greater than V select , and, in addition, a desired speed is selected by operating one of keys 12 , 14 , 18 , which is greater than V select .
[0058] A change from state 38 “override S&R” into state 40 “override ACC” (arrow T 7 ) takes place only when actual speed V is greater than V select (35 km/h) but less than threshold value V SRs (45 km/h), and, in addition, the desired speed is set to a greater value than V select , by operating one of keys 12 , 14 , 18 . As a result, in order to get into the ACC mode by operating the gas pedal, the driver has to operate one of keys 12 , 14 , 18 while the speed is in the interval between 35 and 45 km/h. Thereby, the driver is made aware that he is now leaving the S&R mode, in which the function “braking to a standstill” is available. If the driver misses or deliberately omits operating one of the keys in this speed interval, the behavior of decision unit 24 depends on actual speed V. If this remains less than 45 km/h, the system returns to state 36 (arrow T 6 ) until the driver lets go of the gas pedal. Otherwise, the speed controller is deactivated (arrow T 16 ).
[0059] The transition from state 34 “ACC active” to state 36 “S&R active” takes place automatically as soon as actual speed V decreases to below the minimum speed V ACCmin for the ACC mode (arrow T 10 ).
[0060] A transition from state 40 “override ACC” to state 38 (override S&R), corresponding to arrow T 11 in the previous exemplary embodiment is not provided in this specific embodiment. If the speed of the vehicle decreases to below the minimum speed for ACC while the driver operates the pedal, such as when driving on steep hills, and the driver then lets go of the gas pedal, the transition into state 36 “S&R active” takes place via state 34 (arrows T 8 and T 10 ). However, if the driver accelerates again, so that the speed increases above V ACCmin again before the driver lets go of the gas pedal, the system remains in the ACC mode. This will generally also correspond to the expectation of the driver.
[0061] When the speed controller is in state 36 “S&R active”, a deactivation takes place according to arrow T 14 in this specific embodiment, not only by operating off key 16 , but also automatically when one of the following conditions is fulfilled:
a) The target object followed up to now gets lost and is also not found again before time t, counted by timer 26 , reaches the value T 1 (5 s). b) The distance d of the preceding vehicle becomes greater than the parameter d SRoff (50 m) c) The current speed becomes greater than the threshold value V SRs (45 km/h), for example, during steep downhill driving, and the driver does not operate any of the keys 12 , 14 or 18 .
[0065] By checking these conditions it is ensured that the S&R mode is active only when the speed controller is also able safely to fulfill the functions provided in this mode. | A speed controller for motor vehicles having an input device for the input of a desired speed V set by the driver, and having a plurality of operating modes which are able to be activated in different speed ranges and differ in their functional scope. A change in the operating mode, which results in the loss of a safety-relevant function, is provided or enabled by a command of the driver, characterized by a decision unit, which, in the light of predefined criteria, determines whether a change in the desired speed V set , which is input by the driver, is to be interpreted as a command for changing the operating mode. | 1 |
BACKGROUND
1. Field of the Invention
The present invention generally relates to hot runners and, particularly, to a hot runner used in a mold assembly.
2. Description of Related Art
Insert molding technology using molding machines is a popular molding method. A typical molding machine usually includes a hot runner, a male mold and a female mold. The male mold and the female mold define a mold cavity therebetween. The male mold has a passage defined therein, communicating with the mold cavity. The hot runner is inserted into the passage. Thus, melted plastic can be injected into the mold cavity through the hot runner.
To prevent the melted plastic from leaking out of a combining aperture between the hot runner and the passage, a vertical surface is formed on the outside of the hot runner. The vertical surface is an outer peripheral surface surrounding the longitudinal axis of the hot runner. Correspondingly, the passage has a cooperating surface. The vertical surface is tightly attached to the cooperating surface, thus preventing leakage of melted plastic.
However, after repeated usage, a gap may appear between the vertical surface and the cooperating surface because of abrasion, high temperature, and high pressure. Thus, melted plastic may leak to the outer surface of the hot runner, resulting in damaging other elements, i.e., the heating coil and the temperature-sensing equipment.
Thus, there is room for improvement within the art.
BRIEF DESCRIPTION OF THE DRAWINGS
Many aspects of the hot runner and the mold assembly can be better understood with reference to the following drawings. These drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present hot runner and the mold assembly. Moreover, in the drawings like reference numerals designate corresponding parts throughout the several views.
FIG. 1 is a disassembled cross-sectional view of a hot runner, according to an exemplary embodiment.
FIG. 2 is a cross-sectional view of a mold assembly.
FIG. 3 is a cross-sectional view of the mold assembly engaging with the hot runner.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
FIG. 1 shows an exemplary hot runner 10 . The hot runner 10 includes a canal 11 and a heat-shrinkable tube 12 .
The canal 11 is a hollow tube. The canal 11 defines a channel 111 in the center portion therethrough, and includes a sprayer 112 disposed at one distal end thereof, and a heat insulating layer 113 attached to and covering an outer periphery of the sprayer 112 . The sprayer 112 is tapered. The heat insulating layer 113 is also tapered, and configured to insulate the hot runner 10 and a mold assembly 20 (referring to FIG. 2 ) for preventing heat transmission from the hot runner 10 to the mold assembly 20 . The canal 11 has a vertical surface 114 adjacent to the heat insulating layer 113 . The vertical surface 114 is an outer peripheral surface surrounding the longitudinal axis of the hot runner 10 , and has a high machining precision. A heater 115 is positioned on the outside of the other end of the canal 11 opposite to the sprayer 112 . The heater 115 provides heat to the canal 11 to maintain good flowing of melted plastic in the channel 11 .
The heat-shrinkable tube 12 is made of a macromolecular material having different states when at different temperatures, such as polyvinylchlorid (PVC) and etc. At room temperature, the heat-shrinkable tube 12 is in a glass state. At elevated temperatures, the heat-shrinkable tube 12 may shrink and become elastic. When in the glass state, the heat-shrinkable tube 12 has properties similar to plastic. When in the elastic state, the heat-shrinkable tube 12 has properties similar to rubber. Therefore, when heated, the heat-shrinkable tube 12 changes from the glass state to the high-elastic state and automatically shrinks in volume.
Referring to FIG. 3 , when assembling the hot runner 10 , the heat-shrinkable tube 12 covers the vertical surface 114 of the canal 11 , and receives the heat insulating layer 113 therein. The heater 115 is then electrified by a power source (not shown) to generate heat, thereby causing the heat-shrinkable tube 12 to shrink and tightly attach to the contour of the heat insulating layer 113 and the vertical surface 114 .
Referring to FIG. 2 again, a mold assembly 20 includes a male mold 21 and a female mold 22 . The male mold 21 and the female mold 22 cooperatively form a mold cavity 23 therebetween. The male mold 21 defines a passage 24 communicating with the mold cavity 23 . The passage 24 is configured for receiving the hot runner 10 . The passage 24 has an inner wall, including a tapered surface 241 , a cooperating surface 242 and a limiting surface 243 .
Referring to FIG. 3 again, when mounting the hot runner 10 to the mold assembly 20 , the hot runner 10 is inserted into the passage 24 of the mold assembly 20 . The heat-shrinkable tube 12 abuts against the tapered surface 241 . The cooperating surface 242 cooperatively engages with the vertical surface 114 . A periphery wall of the heater 115 is limited by the limiting surface 243 . The heat-shrinkable tube 12 can fill in the gap between the cooperating surface 242 and the vertical surface 114 and the gap between the heat insulating layer 113 and the tapered surface 241 , thus preventing leakage of melted plastic.
It is to be understood, however, that even through numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of sections within the principles of the invention to the full extent indicated by the broad general meaning of the terms, in which the appended claims are expressed. | A hot runner ( 10 ) is provided including a canal ( 11 ) and a heat-shrinkable tube ( 12 ) covering on the canal ( 11 ). The heat-shrinkable tube ( 12 ) can shrink along the canal ( 12 )'s contour when heated. The present invention further provides a mold ( 20 ) using the hot runner. | 1 |
RELATED APPLICATION
This application is a continuation-in-part of application Ser. No. 09/363,661 filed Jul. 15, 1999 to Phillip Bell, Jr. now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a tagball game and more particularly pertains to a method and apparatus of playing a tagball game.
2. Description of the Prior Art
The use of games is known in the prior art. More specifically, games previously devised and utilized for the purpose of playing are known to consist basically of familiar, expected, and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which has been developed for the fulfillment of countless objectives and requirements.
While the known games fulfill their respective, particular objectives and requirements, the aforementioned patents do not describe a method of playing a tagball game as disclosed herein.
In this respect, the tagball game method and apparatus according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in doing so provides a method and apparatus primarily developed for the purpose of playing a new tagball game.
Therefore, it can be appreciated that there exists a continuing need for new games which can be used for playing. In this regard, the present invention substantially fulfills this need.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the known types of games now present in the prior art, the present invention provides an improved tagball game method and apparatus. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a game method and apparatus which has all the advantages of the prior art and none of the disadvantages.
To attain this, the present invention essentially comprises a method and apparatus for playing a game. The first step in the method is dividing the players into two teams with 2 or more players, preferably about 7 and generally no more than 35 players per team. The method further includes providing a vest for each of the players. Each team has a distinguishing color vest. The external surface of the vest has a pile-type surface. Bull's-eyes are provided on the front and back of the vest. Numerical values are provided on the bull's-eyes. The method also includes a plurality of objects to be projected from one player toward a bull's-eye of a player on the opposite team. The objects are provided with a pile-type surface. In this manner, if the object strikes a bull's-eye, the object is retained on the vest by means of the pile-type surface. The method includes awarding 5 points to the player striking the target of an opposing player in a bull's-eye area. The player is removed from the game for the reminder of the period if a bull's-eye on his vest has been struck. The method further includes awarding 1 point to the player striking the vest of an opposing player in an area other than the bull's-eye area. The player is removed from the game for 2 minutes if an area on his vest other than the bull's-eye area is struck. The method includes providing a quantity of flags. The flags are to be protected by one team. The flags are to be taken by the opposite team. The method also includes dividing the play of game into three periods. Each period is between about 10 and 15 minutes in length. Each subsequent period is shorter than the first. The time between periods is shorter than the time between prior periods. Players throw their objects and capture flags until the time period has elapsed. Finally, the method includes counting the flags acquired and points scored through the throwing of the objects. If one team wins the first and second periods, they have won the game and a third period is not played.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims attached.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of descriptions and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
It is therefore an object of the present invention to provide a method and apparatus of playing a tagball game which has all of the advantages of the prior art games and none of the disadvantages.
It is another object of the present invention to provide a method and apparatus of playing a tagball game which may be easily and efficiently manufactured and marketed and played.
An even further object of the present invention is to provide a tagball game method which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such tagball game economically available to the buying public.
Lastly, it is an object of the present invention to provide a method and apparatus for playing a ball game and the associated vest. The method includes dividing the players into two teams; providing a vest for each of the players, with the external surface of the vest being provided with a pile-type surface and with a bull's-eye; providing a pile-type surface on a plurality of objects to be projected; taking players out of the game and awarding points for players struck; providing a quantity of flags to be protected by one team and to be taken by the opposite team; dividing the play of game into three periods; and counting the flags acquired and points scored through the throwing of the objects.
These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated preferred embodiments of the invention.
DESCRIPTION OF THE FIGURES
FIG. 1 is a front view of the vest of the present invention.
FIG. 2 is a side view of the vest of the present invention.
FIG. 3 is a back view of the vest of the present invention.
FIG. 4 is a top view of the vest of the present invention.
FIG. 5 is an illustration of additional apparel associated with the present invention.
FIG. 6 is an illustration of a bean bag ball used with the present invention.
FIG. 7 is an illustration of a player wearing the vest of the present invention.
FIG. 8 is an illustration of a CO 2 powered gun used in an alternate embodiment of the present invention.
FIG. 9 is a flow chart showing the steps of the method of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention involves a tagball vest and other apparel. A tagball vest 12 is adapted to be used during a game of tagball. The tagball vest comprises a pair of torso-shaped pieces of fabric 14 , 16 . The pieces of fabric form a front portion 14 and back portion 16 . Each portion has an inside face 18 , 20 and an outside face 22 , 24 . The pieces of Fabric are made of a heavy felt material of a first color. All the edges of the fabric are preferably serged. The edges could also be unfinished or hemmed. The torso-shaped pieces are adapted to receive a pile-type fastener covered object 26 utilized in a game of tagball. Each torso-shaped piece has a pair of shoulder extensions 28 . The shoulder extension of the associated front and back portions are sewn together with a serged seam 30 . In this manner a pair of shoulder straps 32 , a head opening 34 and a pair of side openings 36 are formed.
The tagball vest is also comprised of a pair of side straps. The side straps are of an elastomeric material. The side straps have a first end 40 and second end 42 . The first end is sewn to the inside face of the back portion. Sewn to the second end is a pile-type fastener 44 .
Next, the tagball vest has a second pile-type fastener 48 . The second pile-type fastener is sewn to the outside face of the front portion. The second pile-type fastener is adapted to receive the pile-type fastener of the strap enabling it to be coupled to a user and be adapted to accommodate different sized users.
Finally, the tagball vest includes two rings 52 , 54 of fabric on the front portion and two similar rings of fabric on the back portion 51 , 53 . These rings are of a second color. The rings are centered on the outside face of the front portion and the back portion. The preferred method of attachment is sewing. Each ring has an inner circumference and an outer circumference. Each ring has the same distance between the inner circumference and the outer circumference. The first ring 51 , 52 is larger than the second ring 53 , 54 . The rings are positioned to form a bull's-eye as illustrated in FIGS. 1 and 3.
Other apparel shown in FIG. 5 includes foam head gear 56 and a face shield 58 . The head gear and face shield protect a user's head and face during the game. Pants 60 are also included. The pants are of the same material as the vest. The pants also have a pile-type flap 62 making the pants adjustable. The pants have padding 64 in the knee, hip and rear regions to further protect the player.
In an alternate embodiment of the present invention, the shoulder extensions of the front and back portions of the vest are coupled by second pile-type strips 66 . In this manner the vest may be more easily put on and removed.
The object may be of many shapes and sizes. One example is a pile-type surface covered bean bag ball 68 as illustrated in FIG. 6 . Another example is pile-type surface covered bullets 70 adapted to be shot from a CO 2 powered gum 72 as illustrated in FIG. 8 .
The present invention also includes a tagball game method which is a combination of two popular games, “capture the flag” and darts. Players have the option of wearing vests or suits with pile-type surface areas that indicate various point values. Players have the option of using pile-type covered objects, preferably balls or bean bags 68 . Another option is the use of pile-type surface covered pellets or bullets 70 which can be fired from a CO 2 powered gun 72 . The vests or suits worn in the game have a circular pattern 52 on the front with an area at the center, a bull's-eye, known as the kill zone. Striking a player in this area eliminates him from the period of the game and earns 5 points. Striking a player on any other area of the vest or suit earns the striking player 1 point and the struck player is removed from the game for 2 minutes. Tagball is divided into three periods, each lasting between about 10 and 15 minutes. Vests or suits used in tagball are made of pile-type material.
The game of the present invention is an organized team sport that combines the popular games of “capture the flag” and darts. It is designed as a fast paced exhilarating sport that promotes team building as well as physical fitness. Tagball can be played almost anywhere, by persons of any age, gender, or skill level. While providing the same adrenalin rush as paintball, tagball's optional features allow the game to be played without the legal restrictions of fire arm simulations. Tagball can be easily modified to suit those who prefer a more military war game version, or those who prefer playground fun with backyard friends, family or schoolmates.
Regarding equipment, players have the option of wearing pile-type adherent “scoring vest/suits”. The objects used are pile-type surface covered and can be thrown or fired from a CO 2 powered cartridge gun. The pile-type bullet is softer than a paintball pellet, lessening the potential for injury or property damage. The “scoring vests/suits” include a circular pattern twelve inches in diameter on the front and/or back, similar to that of a dart board. Areas on this circular pattern and other areas of the suit have various point values.
Regarding the rules, the game is divided into three periods. Each period lasts between about 10 and 15 minutes. Two timeouts are allowed per period. A 10-minute break is allowed between the first and second periods, and a 5-minute break is allowed between the second and third periods. If the number of players on each team exceeds ten, two flags should be used per team along with two flag goalies. The center of the pattern on the front and/or back of the vest/suit is known as the kill zone. If a player is struck in this zone, he must sit out for the remainder of the period and the striking player earns 5 points. If a player is struck in another area, one point is earned and the struck player must sit out the game for 2 minutes. The team capturing the most flags in two periods wins. If no flags are captured, the game will be won by the team scoring the most points.
Tagball is a poor man's war game where players wear specially made pile-type adherent uniforms and/or vests. Pile-type covered balls are thrown to “tag” players on the opposing team. The object of the game is to win by capturing the other team's flag. Players who are struck by a ball that attaches to their kill zone area on the vest or uniforms are eliminated from the period of the game. Only a “live” player can capture a team's flag. The game should be played in three 10 to 15-minute periods. The team that captures the flag two out of three periods, the team having the least eliminated players in two periods, or the team with the greatest amount of points wins. There should be between about 7 and 35 players on each team and between about 2 and 3 referees.
Players should wear special uniforms/vests equipped with padding. Arm and knee pads should be worn, especially when playing in wooded areas. Other apparel, cushioned karate-type head gear and face shields should also be worn. The objects used in the game are pile-type covered balls or pile-type covered bean bags.
As can be understood from the foregoing, tagball is a new game presented as an organized team sport. Tagball/bag is a poor man's war game which combines the game of “caoture the flag” and the dart board/tag concept. The object of the game is to avoid being hit by the opposite team's objects before capturing the opposite team's flag within a time limit of 2 to 3 periods. A third period is only necessary when a team falls to stop the opposing team from capturing the flag in the first two 15-minute periods of the game. Between the first two periods, a 7-minute break and strategy session occurs. Between the second and third periods, a 5-minute break occurs. If a flag has not been captured by the end of the third period, victory goes to the team having eliminated more opposing members. The game needs about 2 to 4 overseeing officials or referees.
Another form of the game is tagball/bag featuring two opposing teams made up of between about 7 and 10 players. Players wear vests/uniforms featuring pile-type adherent bull's-eye targets on the fronts of their vests. Older youth and adult players throw pile-type adherent, tennis ball sized bean bag balls. A pile-type adherent bean bag is used by very young children. The apparatus used for playing the game consists of essentially a pile-type adherent bull's-eye vest and a pile-type adherent ball or bean bag.
The object of this fast paced, exhilarating sport is to promote team building, physical fitness, eye hand coordination, and provide a non-injurious alternative contact sport for all ages and both genders. The game can be played as a basic elimination game in the woods, outdoor playing fields, with obstacles, in gyms, multipurpose rooms, tennis or basketball courts. Tagball/bag can be played almost anywhere by anyone.
While providing the same adrenalin rush as football and paintball, tagball/bag's optional features allow the game to be played without the legal, environmental, or economic limitations that may be incurred with paintball or football. The likelihood of injury is also reduced.
Tagball/bag can be easily modified to suit those who prefer a more military war game version, football play experience or for an indoor activity in a gymnasium. However, tagbag, for the younger children, can be played in a multipurpose room, and/or backyard with family, friends or schoolmates.
From the descriptions herein above of the method of playing the tagball game of the present invention, it can be appreciated that:
1. Tagball/bag is an organized team sport which is a combination of the popular games “capture the flag”, darts and tag.
2. Tagball/bag promotes team building as well as physical fitness.
3. Depending on age, players have the option of using pile-type surface covered balls or bean bags.
4. Tagball/bag is a dynamic, fast paced, and exhilarating dart board game with a tag concept.
5. There are two ways to win in tagball/bag: eliminating a player by striking a bull's-eye target, or kill zone, on the player's vest or accumulating the greatest number of points.
6. Tagball/bag can be played in three 15-minute periods or as an unlimited time activity.
7. Tagball/bag vest or suits could be made of plastic and used in a traditional paintball game.
As to the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art. it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | The present invention includes a method and apparatus for playing a ball game and the associated vest. The method includes: dividing the players into two teams; providing a vest for each of the players, with the external surface of the vest being provided with a pile-type surface and bull's-eyes; providing a plurality of objects with a pile-type surface; awarding points to the player striking the opposing player and removing the struck player from the game; providing a quantity of flags to be protected by one team and taken by the other team; dividing the play of game into three periods; and counting the flags acquired and points scored through the throwing of the objects. | 8 |
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 14/862,679, filed on Sep. 23, 2015, which is a continuation of U.S. patent application Ser. No. 14/198,764, filed on Mar. 6, 2014, which is a continuation of U.S. patent application Ser. No. 13/944,320, filed on Jul. 17, 2013, which is a continuation of Ser. No. 13/678,983, filed Nov. 16, 2012, which is a continuation of U.S. patent application Ser. No. 12/279,398, filed on Oct. 19, 2009, now U.S. Pat. No. 8,383,855, issued on Feb. 26, 2013, which is a national phase application under 35 U.S.C. §371 of PCT International Application No. PCT/US2007/062152, filed on Feb. 14, 2007, which claims priority under 35 U.S.C. §119(e) to U.S. provisional patent application, U.S. Ser. No. 60/773,172, filed Feb. 14, 2006. Each of these prior applications is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The identification of small organic molecules that affect specific biological functions is an endeavor that impacts both biology and medicine. Such molecules are useful as therapeutic agents and as probes of biological function. In but one example from the emerging field of chemical genetics, in which small molecules can be used to alter the function of biological molecules to which they bind, these molecules have been useful at elucidating signal transduction pathways by acting as chemical protein knockouts, thereby causing a loss of protein function (Schreiber et al., J. Am. Chem. Soc., 1990, 112, 5583; Mitchison, Chem. and Biol., 1994, 1, 3). Additionally, due to the interaction of these small molecules with particular biological targets and their ability to affect specific biological function, they may also serve as candidates for the development of therapeutics. One important class of small molecules, natural products, which are small molecules obtained from nature, clearly have played an important role in the development of biology and medicine, serving as pharmaceutical leads, drugs (Newman et al., Nat. Prod. Rep. 2000, 17, 215-234), and powerful reagents for studying cell biology (Schreiber, S. L. Chem. and Eng. News 1992 (October 26), 22-32).
[0003] Because it is difficult to predict which small molecules will interact with a biological target, and it is oftent difficult to obtain and synthesize efficiently small molecules found in nature, intense efforts have been directed towards the generation of large numbers, or libraries, of small organic compounds, often “natural product-like” libraries. These libraries can then be linked to sensitive screens for a particular biological target of interest to identify the active molecules.
[0004] One biological target of recent interest is histone deacetylase (see, for example, a discussion of the use of inhibitors of histone deacetylases for the treatment of cancer: Marks et al. Nature Reviews Cancer 2001, 1, 194; Johnstone et al. Nature Reviews Drug Discovery 2002, 1, 287). Post-translational modification of proteins through acetylation and deacetylation of lysine residues has a critical role in regulating their cellular functions. HDACs are zinc hydrolases that modulate gene expression through deacetylation of the N-acetyl-lysine residues of histone proteins and other transcriptional regulators (Hassig et al. Curr. Opin. Chem. Biol. 1997, 1, 300-308). HDACs participate in cellular pathways that control cell shape and differentiation, and an HDAC inhibitor has been shown effective in treating an otherwise recalcitrant cancer (Warrell et al. J. Natl. Cancer Inst. 1998, 90, 1621-1625). Eleven human HDACs, which use Zn as a cofactor, have been characterized (Taunton et al. Science 1996, 272, 408-411; Yang et al. J. Biol. Chem. 1997, 272, 28001-28007; Grozinger et al. Proc. Natl. Acad. Sci. U.S.A. 1999, 96, 4868-4873; Kao et al. Genes Dev. 2000, 14, 55-66; Hu et al. J. Biol. Chem. 2000, 275, 15254-15264; Zhou et al. Proc. Natl. Acad. Sci. U.S.A. 2001, 98, 10572-10577; Venter et al. Science 2001, 291, 1304-1351). These members fall into three related classes (class I, II, and III). An additional seven HDACs have been identified which use NAD as a confactor. To date, no small molecules are known that selectively target either the two classes or individual members of this family ((for example ortholog-selective HDAC inhibitors have been reported: (a) Meinke et al. J. Med. Chem. 2000, 14, 4919-4922; (b) Meinke, et al. Curr. Med. Chem. 2001, 8, 211-235).
SUMMARY OF THE INVENTION
[0005] The present invention provides novel histone deacetylase inhibitors and methods of preparing and using these compounds. The inventive HDAC inhibitors comprise an esterase-sensitive ester linkage, thereby when the compound is exposed to an esterase such as in the bloodstream the compound is inactivated. The compounds are particularly useful in the treatment of skin disorders such as cutaneous T-cell lymphoma, neurofibromatosis, psoriasis, hair loss, dermatitis, baldness, and skin pigmentation. The inventive compound is administered topically to the skin of the patient where it is clinically active. Once the compound is absorbed into the body, it is quickly inactivated by esterases which cleave the compound into two or more biologically inactive fragments. Thus, allowing for high local concentrations (e.g., in the skin) and reduced systemic toxicity. In certain embodiments, the compound is fully cleaved upon exposure to serum in less than 5 min., preferably less than 1 min.
[0006] The present invention provides novel compounds of general formula (I),
[0000]
[0000] and pharmaceutical compositions thereof, as described generally and in subclasses herein, which compounds are useful as inhibitors of histone deacetylases or other deacetylases, and thus are useful for the treatment of proliferative diseases. The inventive compounds are additionally useful as tools to probe biological function. In certain embodiments, the compounds of the invention are particularly useful in the treatment of skin disorders. The ester linkage is susceptible to esterase cleavage, particularly esterases found in the blood. Therefore, these compounds may be administered topically to treat skin disorders, such as cutaneous T-cell lymphoma, psoriasis, hair loss, dermatitis, etc., without the risk of systemic effects. Once the compound enters the bloodstream it is quickly degraded by serum esterases. Preferably, the compound is degraded into non-toxic, biologically inactive by-products.
[0007] In another aspect, the present invention provides methods for inhibiting histone deacetylase activity or other deacetylase activity in a patient or a biological sample, comprising administering to said patient, or contacting said biological sample with an effective inhibitory amount of a compound of the invention. In certain embodiments, the compounds specifically inhibit a particular HDAC (e.g., HDAC1, HDAC2, HDAC3, HDAC4, HDAC4, HDAC5, HDAC6, HDAC7, HDAC8, HDAC9, HDAC10, HDAC11) or class of HDACs (e.g., Class I, II, or III). In certain embodiments, the compounds specifically inhibit HDAC6. In still another aspect, the present invention provides methods for treating skin disorders involving histone deacetylase activity, comprising administering to a subject in need thereof a therapeutically effective amount of a compound of the invention. The compounds may be administered by any method known in the art. In certain embodiments, the compounds are administered topically (e.g., in a cream, lotion, ointment, spray, gel, powder, etc.). In certain embodiments, the compound is administered to skin. In other certain embodiments, the compound is administered to hair. The compounds may also be administered intravenously or orally. The invention also provides pharmaceutical compositions of the compounds wherein the compound is combined with a pharmaceutically acceptable excipient.
[0008] In yet another aspect, the present invention provides methods for preparing compounds of the invention and intermediates thereof.
Definitions
[0009] Certain compounds of the present invention, and definitions of specific functional groups are also described in more detail below. For purposes of this invention, the chemical elements are identified in accordance with the Periodic Table of the Elements, CAS version, Handbook of Chemistry and Physics, 75 th Ed., inside cover, and specific functional groups are generally defined as described therein. Additionally, general principles of organic chemistry, as well as specific functional moieties and reactivity, are described in Organic Chemistry , Thomas Sorrell, University Science Books, Sausalito: 1999, the entire contents of which are incorporated herein by reference. Furthermore, it will be appreciated by one of ordinary skill in the art that the synthetic methods, as described herein, utilize a variety of protecting groups. By the term “protecting group,” has used herein, it is meant that a particular functional moiety, e.g., C, O, S, or N, is temporarily blocked so that a reaction can be carried out selectively at another reactive site in a multifunctional compound. In preferred embodiments, a protecting group reacts selectively in good yield to give a protected substrate that is stable to the projected reactions; the protecting group must be selectively removed in good yield by readily available, preferably nontoxic reagents that do not attack the other functional groups; the protecting group forms an easily separable derivative (more preferably without the generation of new stereogenic centers); and the protecting group has a minimum of additional functionality to avoid further sites of reaction. As detailed herein, oxygen, sulfur, nitrogen and carbon protecting groups may be utilized. Exemplary protecting groups are detailed herein, however, it will be appreciated that the present invention is not intended to be limited to these protecting groups; rather, a variety of additional equivalent protecting groups can be readily identified using the above criteria and utilized in the method of the present invention. Additionally, a variety of protecting groups are described in Protective Groups in Organic Synthesis , Third Ed. Greene, T. W. and Wuts, P. G., Eds., John Wiley & Sons, New York: 1999, the entire contents of which are hereby incorporated by reference. Furthermore, a variety of carbon protecting groups are described in Myers, A.; Kung, D. W.; Zhong, B.; Movassaghi, M.; Kwon, S. J. Am. Chem. Soc. 1999, 121, 8401-8402, the entire contents of which are hereby incorporated by reference.
[0010] It will be appreciated that the compounds, as described herein, may be substituted with any number of substituents or functional moieties. In general, the term “substituted” whether preceded by the term “optionally” or not, and substituents contained in formulas of this invention, refer to the replacement of hydrogen radicals in a given structure with the radical of a specified substituent. When more than one position in any given structure may be substituted with more than one substituent selected from a specified group, the substituent may be either the same or different at every position. As used herein, the term “substituted” is contemplated to include all permissible substituents of organic compounds. In a broad aspect, the permissible substituents include acyclic and cyclic, branched and unbranched, carbocyclic and heterocyclic, aromatic and nonaromatic substituents of organic compounds. For purposes of this invention, heteroatoms such as nitrogen may have hydrogen substituents and/or any permissible substituents of organic compounds described herein which satisfy the valencies of the heteroatoms. Furthermore, this invention is not intended to be limited in any manner by the permissible substituents of organic compounds. Combinations of substituents and variables envisioned by this invention are preferably those that result in the formation of stable compounds useful in the treatment, for example of proliferative disorders, including, but not limited to cancer. The term “stable”, as used herein, preferably refers to compounds which possess stability sufficient to allow manufacture and which maintain the integrity of the compound for a sufficient period of time to be detected and preferably for a sufficient period of time to be useful for the purposes detailed herein.
[0011] The term “acyl”, as used herein, refers to a carbonyl-containing functionality, e.g., —C(═O)R′, wherein R′ is an aliphatic, alycyclic, heteroaliphatic, heterocyclic, aryl, heteroaryl, (aliphatic)aryl, (heteroaliphatic)aryl, heteroaliphatic(aryl) or heteroaliphatic(heteroaryl) moiety, whereby each of the aliphatic, heteroaliphatic, aryl, or heteroaryl moieties is substituted or unsubstituted, or is a substituted (e.g., hydrogen or aliphatic, heteroaliphatic, aryl, or heteroaryl moieties) oxygen or nitrogen containing functionality (e.g., forming a carboxylic acid, ester, or amide functionality).
[0012] The term “aliphatic”, as used herein, includes both saturated and unsaturated, straight chain (i.e., unbranched) or branched aliphatic hydrocarbons, which are optionally substituted with one or more functional groups. As will be appreciated by one of ordinary skill in the art, “aliphatic” is intended herein to include, but is not limited to, alkyl, alkenyl, alkynyl moieties. Thus, as used herein, the term “alkyl” includes straight and branched alkyl groups. An analogous convention applies to other generic terms such as “alkenyl”, “alkynyl” and the like. Furthermore, as used herein, the terms “alkyl”, “alkenyl”, “alkynyl” and the like encompass both substituted and unsubstituted groups. In certain embodiments, as used herein, “lower alkyl” is used to indicate those alkyl groups (substituted, unsubstituted, branched or unbranched) having 1-6 carbon atoms.
[0013] In certain embodiments, the alkyl, alkenyl and alkynyl groups employed in the invention contain 1-20 aliphatic carbon atoms. In certain other embodiments, the alkyl, alkenyl, and alkynyl groups employed in the invention contain 1-10 aliphatic carbon atoms. In yet other embodiments, the alkyl, alkenyl, and alkynyl groups employed in the invention contain 1-8 aliphatic carbon atoms. In still other embodiments, the alkyl, alkenyl, and alkynyl groups employed in the invention contain 1-6 aliphatic carbon atoms. In yet other embodiments, the alkyl, alkenyl, and alkynyl groups employed in the invention contain 1-4 carbon atoms. Illustrative aliphatic groups thus include, but are not limited to, for example, methyl, ethyl, n-propyl, isopropyl, allyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, sec-pentyl, isopentyl, tert-pentyl, n-hexyl, sec-hexyl, moieties and the like, which again, may bear one or more substituents. Alkenyl groups include, but are not limited to, for example, ethenyl, propenyl, butenyl, 1-methyl-2-buten-1-yl, and the like. Representative alkynyl groups include, but are not limited to, ethynyl, 2-propynyl (propargy1), 1-propynyl and the like.
[0014] The term “alicyclic”, as used herein, refers to compounds which combine the properties of aliphatic and cyclic compounds and include but are not limited to cyclic, or polycyclic aliphatic hydrocarbons and bridged cycloalkyl compounds, which are optionally substituted with one or more functional groups. As will be appreciated by one of ordinary skill in the art, “alicyclic” is intended herein to include, but is not limited to, cycloalkyl, cycloalkenyl, and cycloalkynyl moieties, which are optionally substituted with one or more functional groups. Illustrative alicyclic groups thus include, but are not limited to, for example, cyclopropyl, —CH 2 -cyclopropyl, cyclobutyl, —CH 2 -cyclobutyl, cyclopentyl, —CH 2 — cyclopentyl-n, cyclohexyl, —CH 2 -cyclohexyl, cyclohexenylethyl, cyclohexanylethyl, norborbyl moieties and the like, which again, may bear one or more substituents.
[0015] The term “alkoxy” (or “alkyloxy”), or “thioalkyl” as used herein refers to an alkyl group, as previously defined, attached to the parent molecular moiety through an oxygen atom or through a sulfur atom. In certain embodiments, the alkyl group contains 1-20 aliphatic carbon atoms. In certain other embodiments, the alkyl group contains 1-10 aliphatic carbon atoms. In yet other embodiments, the alkyl, alkenyl, and alkynyl groups employed in the invention contain 1-8 aliphatic carbon atoms. In still other embodiments, the alkyl group contains 1-6 aliphatic carbon atoms. In yet other embodiments, the alkyl group contains 1-4 aliphatic carbon atoms. Examples of alkoxy, include but are not limited to, methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, tert-butoxy, neopentoxy and n-hexoxy. Examples of thioalkyl include, but are not limited to, methylthio, ethylthio, propylthio, isopropylthio, n-butylthio, and the like.
[0016] The term “alkylamino” refers to a group having the structure —NHR′ wherein R′ is alkyl, as defined herein. The term “aminoalkyl” refers to a group having the structure NH 2 R′—, wherein R′ is alkyl, as defined herein. In certain embodiments, the alkyl group contains 1-20 aliphatic carbon atoms. In certain other embodiments, the alkyl group contains 1-10 aliphatic carbon atoms. In yet other embodiments, the alkyl, alkenyl, and alkynyl groups employed in the invention contain 1-8 aliphatic carbon atoms. In still other embodiments, the alkyl group contains 1-6 aliphatic carbon atoms. In yet other embodiments, the alkyl group contains 1-4 aliphatic carbon atoms. Examples of alkylamino include, but are not limited to, methylamino, ethylamino, iso-propylamino and the like.
[0017] Some examples of substituents of the above-described aliphatic (and other) moieties of compounds of the invention include, but are not limited to aliphatic; heteroaliphatic; aryl; heteroaryl; alkylaryl; alkylheteroaryl; alkoxy; aryloxy; heteroalkoxy; heteroaryloxy; alkylthio; arylthio; heteroalkylthio; heteroarylthio; F; Cl; Br; I; —OH; —NO 2 ; —CN; —CF 3 ; —CH 2 CF 3 ; —CHCl 2 ; —CH 2 OH; —CH 2 CH 2 OH; —CH 2 NH 2 ; —CH 2 SO 2 CH 3 ; —C(O)R x ; —CO 2 (R x ); —CON(R x ) 2 ; —OC(O)R x ; —OCO 2 R x ; —OCON(R x ) 2 ; —N(R x ) 2 ; —S(O) 2 R x ; —NR x (CO)R x wherein each occurrence of R x independently includes, but is not limited to, aliphatic, alycyclic, heteroaliphatic, heterocyclic, aryl, heteroaryl, alkylaryl, or alkylheteroaryl, wherein any of the aliphatic, heteroaliphatic, alkylaryl, or alkylheteroaryl substituents described above and herein may be substituted or unsubstituted, branched or unbranched, cyclic or acyclic, and wherein any of the aryl or heteroaryl substituents described above and herein may be substituted or unsubstituted. Additional examples of generally applicable substituents are illustrated by the specific embodiments shown in the Examples that are described herein.
[0018] In general, the term “aromatic moiety”, as used herein, refers to a stable mono- or polycyclic, unsaturated moiety having preferably 3-14 carbon atoms, each of which may be substituted or unsubstituted. In certain embodiments, the term “aromatic moiety” refers to a planar ring having p-orbitals perpendicular to the plane of the ring at each ring atom and satisfying the Huckel rule where the number of pi electrons in the ring is (4n+2) wherein n is an integer. A mono- or polycyclic, unsaturated moiety that does not satisfy one or all of these criteria for aromaticity is defined herein as “non-aromatic”, and is encompassed by the term “alicyclic”.
[0019] In general, the term “heteroaromatic moiety”, as used herein, refers to a stable mono- or polycyclic, unsaturated moiety having preferably 3-14 carbon atoms, each of which may be substituted or unsubstituted; and comprising at least one heteroatom selected from O, S and N within the ring (i.e., in place of a ring carbon atom). In certain embodiments, the term “heteroaromatic moiety” refers to a planar ring comprising at least on heteroatom, having p-orbitals perpendicular to the plane of the ring at each ring atom, and satisfying the Huckel rule where the number of pi electrons in the ring is (4n+2) wherein n is an integer.
[0020] It will also be appreciated that aromatic and heteroaromatic moieties, as defined herein may be attached via an alkyl or heteroalkyl moiety and thus also include -(alkyl)aromatic, -(heteroalkyl)aromatic, -(heteroalkyl)heteroaromatic, and -(heteroalkyl)heteroaromatic moieties. Thus, as used herein, the phrases “aromatic or heteroaromatic moieties” and “aromatic, heteroaromatic, -(alkyl)aromatic, -(heteroalkyl)aromatic, -(heteroalkyl)heteroaromatic, and -(heteroalkyl)heteroaromatic” are interchangeable. Substituents include, but are not limited to, any of the previously mentioned substituents, i.e., the substituents recited for aliphatic moieties, or for other moieties as disclosed herein, resulting in the formation of a stable compound.
[0021] The term “aryl”, as used herein, does not differ significantly from the common meaning of the term in the art, and refers to an unsaturated cyclic moiety comprising at least one aromatic ring. In certain embodiments, “aryl” refers to a mono- or bicyclic carbocyclic ring system having one or two aromatic rings including, but not limited to, phenyl, naphthyl, tetrahydronaphthyl, indanyl, indenyl and the like.
[0022] The term “heteroaryl”, as used herein, does not differ significantly from the common meaning of the term in the art, and refers to a cyclic aromatic radical having from five to ten ring atoms of which one ring atom is selected from S, O and N; zero, one or two ring atoms are additional heteroatoms independently selected from S, O and N; and the remaining ring atoms are carbon, the radical being joined to the rest of the molecule via any of the ring atoms, such as, for example, pyridyl, pyrazinyl, pyrimidinyl, pyrrolyl, pyrazolyl, imidazolyl, thiazolyl, oxazolyl, isooxazolyl, thiadiazolyl, oxadiazolyl, thiophenyl, furanyl, quinolinyl, isoquinolinyl, and the like.
[0023] It will be appreciated that aryl and heteroaryl groups (including bicyclic aryl groups) can be unsubstituted or substituted, wherein substitution includes replacement of one or more of the hydrogen atoms thereon independently with any one or more of the following moieties including, but not limited to: aliphatic; alicyclic; heteroaliphatic; heterocyclic; aromatic; heteroaromatic; aryl; heteroaryl; alkylaryl; heteroalkylaryl; alkylheteroaryl; heteroalkylheteroaryl; alkoxy; aryloxy; heteroalkoxy; heteroaryloxy; alkylthio; arylthio; heteroalkylthio; heteroarylthio; F; Cl; Br; I; —OH; —NO 2 ; —CN; —CF 3 ; —CH 2 CF 3 ; —CHCl 2 ; —CH 2 OH; —CH 2 CH 2 OH; —CH 2 NH 2 ; —CH 2 SO 2 CH 3 ; —C(O)R x ; —CO 2 (R x ); —CON(R x ) 2 ; —OC(O)R x ; —OCO 2 R x ; —OCON(R x ) 2 ; —N(R x ) 2 ; —S(O)R x ; —S(O) 2 R x ; —NR x (CO)R x wherein each occurrence of R x independently includes, but is not limited to, aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic, heteroaromatic, aryl, heteroaryl, alkylaryl, alkylheteroaryl, heteroalkylaryl or heteroalkylheteroaryl, wherein any of the aliphatic, alicyclic, heteroaliphatic, heterocyclic, alkylaryl, or alkylheteroaryl substituents described above and herein may be substituted or unsubstituted, branched or unbranched, saturated or unsaturated, and wherein any of the aromatic, heteroaromatic, aryl, heteroaryl, -(alkyl)aryl or -(alkyl)heteroaryl substituents described above and herein may be substituted or unsubstituted. Additionally, it will be appreciated, that any two adjacent groups taken together may represent a 4, 5, 6, or 7-membered substituted or unsubstituted alicyclic or heterocyclic moiety. Additional examples of generally applicable substituents are illustrated by the specific embodiments shown in the Examples that are described herein.
[0024] The term “cycloalkyl”, as used herein, refers specifically to groups having three to seven, preferably three to ten carbon atoms. Suitable cycloalkyls include, but are not limited to cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and the like, which, as in the case of aliphatic, alicyclic, heteroaliphatic or heterocyclic moieties, may optionally be substituted with substituents including, but not limited to aliphatic; alicyclic; heteroaliphatic; heterocyclic; aromatic; heteroaromatic; aryl; heteroaryl; alkylaryl; heteroalkylaryl; alkylheteroaryl; heteroalkylheteroaryl; alkoxy; aryloxy; heteroalkoxy; heteroaryloxy; alkylthio; arylthio; heteroalkylthio; heteroarylthio; F; Cl; Br; I; —OH; —NO 2 ; —CN; —CF 3 ; —CH 2 CF 3 ; —CHCl 2 ; —CH 2 OH; —CH 2 CH 2 OH; —CH 2 NH 2 ; —CH 2 SO 2 CH 3 ; —C(O)R x ; —CO 2 (R x ); —CON(R x ) 2 ; —OC(O)R x ; —OCO 2 R x ; —OCON(R x ) 2 ; —N(R x ) 2 ; —S(O) 2 R x ; —NR x (CO)R x wherein each occurrence of R x independently includes, but is not limited to, aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic, heteroaromatic, aryl, heteroaryl, alkylaryl, alkylheteroaryl, heteroalkylaryl or heteroalkylheteroaryl, wherein any of the aliphatic, alicyclic, heteroaliphatic, heterocyclic, alkylaryl, or alkylheteroaryl substituents described above and herein may be substituted or unsubstituted, branched or unbranched, saturated or unsaturated, and wherein any of the aromatic, heteroaromatic, aryl or heteroaryl substituents described above and herein may be substituted or unsubstituted. Additional examples of generally applicable substituents are illustrated by the specific embodiments shown in the Examples that are described herein.
[0025] The term “heteroaliphatic”, as used herein, refers to aliphatic moieties in which one or more carbon atoms in the main chain have been substituted with a heteroatom. Thus, a heteroaliphatic group refers to an aliphatic chain which contains one or more oxygen, sulfur, nitrogen, phosphorus or silicon atoms, e.g., in place of carbon atoms. Heteroaliphatic moieties may be linear or branched, and saturated or unsaturated. In certain embodiments, heteroaliphatic moieties are substituted by independent replacement of one or more of the hydrogen atoms thereon with one or more moieties including, but not limited to aliphatic; alicyclic; heteroaliphatic; heterocyclic; aromatic; heteroaromatic; aryl; heteroaryl; alkylaryl; alkylheteroaryl; alkoxy; aryloxy; heteroalkoxy; heteroaryloxy; alkylthio; arylthio; heteroalkylthio; heteroarylthio; F; Cl; Br; I; —OH; —NO 2 ; —CN; —CF 3 ; —CH 2 CF 3 ; —CHCl 2 ; —CH 2 OH; —CH 2 CH 2 OH; —CH 2 NH 2 ; —CH 2 SO 2 CH 3 ; —C(O)R x ; —CO 2 (R x ); —CON(R x ) 2 ; —OC(O)R x ; —OCO 2 R x ; —OCON(R x ) 2 ; —N(R x ) 2 ; —S(O) 2 R x ; —NR x (CO)R x wherein each occurrence of R x independently includes, but is not limited to, aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic, heteroaromatic, aryl, heteroaryl, alkylaryl, alkylheteroaryl, heteroalkylaryl or heteroalkylheteroaryl, wherein any of the aliphatic, alicyclic, heteroaliphatic, heterocyclic, alkylaryl, or alkylheteroaryl substituents described above and herein may be substituted or unsubstituted, branched or unbranched, saturated or unsaturated, and wherein any of the aromatic, heteroaromatic, aryl or heteroaryl substituents described above and herein may be substituted or unsubstituted. Additional examples of generally applicable substituents are illustrated by the specific embodiments shown in the Examples that are described herein.
[0026] The term “heterocycloalkyl”, “heterocycle” or “heterocyclic”, as used herein, refers to compounds which combine the properties of heteroaliphatic and cyclic compounds and include, but are not limited to, saturated and unsaturated mono- or polycyclic cyclic ring systems having 5-16 atoms wherein at least one ring atom is a heteroatom selected from O, S and N (wherein the nitrogen and sulfur heteroatoms may be optionally be oxidized), wherein the ring systems are optionally substituted with one or more functional groups, as defined herein. In certain embodiments, the term “heterocycloalkyl”, “heterocycle” or “heterocyclic” refers to a non-aromatic 5-, 6-, or 7-membered ring or a polycyclic group wherein at least one ring atom is a heteroatom selected from O, S and N (wherein the nitrogen and sulfur heteroatoms may be optionally be oxidized), including, but not limited to, a bi- or tri-cyclic group, comprising fused six-membered rings having between one and three heteroatoms independently selected from oxygen, sulfur and nitrogen, wherein (i) each 5-membered ring has 0 to 2 double bonds, each 6-membered ring has 0 to 2 double bonds and each 7-membered ring has 0 to 3 double bonds, (ii) the nitrogen and sulfur heteroatoms may be optionally be oxidized, (iii) the nitrogen heteroatom may optionally be quaternized, and (iv) any of the above heterocyclic rings may be fused to an aryl or heteroaryl ring. Representative heterocycles include, but are not limited to, heterocycles such as furanyl, thiofuranyl, pyranyl, pyrrolyl, thienyl, pyrrolidinyl, pyrazolinyl, pyrazolidiny1, imidazolinyl, imidazolidinyl, piperidinyl, piperazinyl, oxazolyl, oxazolidinyl, isooxazolyl, isoxazolidinyl, dioxazolyl, thiadiazolyl, oxadiazolyl, tetrazolyl, triazolyl, thiatriazolyl, oxatriazolyl, thiadiazolyl, oxadiazolyl, morpholinyl, thiazolyl, thiazolidinyl, isothiazolyl, isothiazolidinyl, dithiazolyl, dithiazolidinyl, tetrahydrofuryl, and benzofused derivatives thereof. In certain embodiments, a “substituted heterocycle, or heterocycloalkyl or heterocyclic” group is utilized and as used herein, refers to a heterocycle, or heterocycloalkyl or heterocyclic group, as defined above, substituted by the independent replacement of one, two or three of the hydrogen atoms thereon with but are not limited to aliphatic; alicyclic; heteroaliphatic; heterocyclic; aromatic; heteroaromatic; aryl; heteroaryl; alkylaryl; heteroalkylaryl; alkylheteroaryl; heteroalkylheteroaryl; alkoxy; aryloxy; heteroalkoxy; heteroaryloxy; alkylthio; arylthio; heteroalkylthio; heteroarylthio; F; Cl; Br; I; —OH; —NO 2 ; —CN; —CF 3 ; —CH 2 CF 3 ; —CHCl 2 ; —CH 2 OH; —CH 2 CH 2 OH; —CH 2 NH 2 ; —CH 2 SO 2 CH 3 ; —C(O)R x ; —CO 2 (R x ); —CON(R x ) 2 ; —OC(O)R x ; —OCO 2 R x ; —OCON(R x ) 2 ; —N(R x ) 2 ; —S(O) 2 R x ; —NR x (CO)R x wherein each occurrence of R x independently includes, but is not limited to, aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic, heteroaromatic, aryl, heteroaryl, alkylaryl, alkylheteroaryl, heteroalkylaryl or heteroalkylheteroaryl, wherein any of the aliphatic, alicyclic, heteroaliphatic, heterocyclic, alkylaryl, or alkylheteroaryl substituents described above and herein may be substituted or unsubstituted, branched or unbranched, saturated or unsaturated, and wherein any of the aromatic, heteroaromatic, aryl or heteroaryl substitutents described above and herein may be substituted or unsubstituted. Additional examples or generally applicable substituents are illustrated by the specific embodiments shown in the Examples, which are described herein.
[0027] Additionally, it will be appreciated that any of the alicyclic or heterocyclic moieties described above and herein may comprise an aryl or heteroaryl moiety fused thereto. Additional examples of generally applicable substituents are illustrated by the specific embodiments shown in the Examples that are described herein. The terms “halo” and “halogen” as used herein refer to an atom selected from fluorine, chlorine, bromine and iodine.
[0028] The terms “halo” and “halogen” as used herein refer to an atom selected from fluorine, chlorine, bromine, and iodine.
[0029] The term “haloalkyl” denotes an alkyl group, as defined above, having one, two, or three halogen atoms attached thereto and is exemplified by such groups as chloromethyl, bromoethyl, trifluoromethyl, and the like.
[0030] The term “amino”, as used herein, refers to a primary (—NH 2 ), secondary (—NHR x ), tertiary (—NR x R y ) or quaternary (—N + R x R y R z ) amine, where R x , R y and R z are independently an aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic or heteroaromatic moiety, as defined herein. Examples of amino groups include, but are not limited to, methylamino, dimethylamino, ethylamino, diethylamino, diethylaminocarbonyl, methylethylamino, iso-propylamino, piperidino, trimethylamino, and propylamino.
[0031] The term “alkylidene”, as used herein, refers to a substituted or unsubstituted, linear or branched saturated divalent radical consisting solely of carbon and hydrogen atoms, having from one to n carbon atoms, having a free valence “-” at both ends of the radical.
[0032] The term “alkenylidene”, as used herein, refers to a substituted or unsubstituted, linear or branched unsaturated divalent radical consisting solely of carbon and hydrogen atoms, having from two to n carbon atoms, having a free valence “-” at both ends of the radical, and wherein the unsaturation is present only as double bonds and wherein a double bond can exist between the first carbon of the chain and the rest of the molecule.
[0033] The term “alkynylidene”, as used herein, refers to a substituted or unsubstituted, linear or branched unsaturated divalent radical consisting solely of carbon and hydrogen atoms, having from two to n carbon atoms, having a free valence “-” at both ends of the radical, and wherein the unsaturation is present only as triple bonds and wherein a triple bond can exist between the first carbon of the chain and the rest of the molecule.
[0034] Unless otherwise indicated, as used herein, the terms “alkyl”, “alkenyl”, “alkynyl”, “heteroalkyl”, “heteroalkenyl”, “heteroalkynyl”, “alkylidene”, alkenylidene”, -(alkyl)aryl, -(heteroalkyl)aryl, -(heteroalkyl)aryl, -(heteroalkyl)heteroaryl, and the like encompass substituted and unsubstituted, and linear and branched groups. Similarly, the terms “aliphatic”, “heteroaliphatic”, and the like encompass substituted and unsubstituted, saturated and unsaturated, and linear and branched groups. Similarly, the terms “cycloalkyl”, “heterocycle”, “heterocyclic”, and the like encompass substituted and unsubstituted, and saturated and unsaturated groups. Additionally, the terms “cycloalkenyl”, “cycloalkynyl”, “heterocycloalkenyl”, “heterocycloalkynyl”, “aromatic”, “heteroaromatic, “aryl”, “heteroaryl” and the like encompass both substituted and unsubstituted groups.
[0035] The phrase, “pharmaceutically acceptable derivative”, as used herein, denotes any pharmaceutically acceptable salt, ester, or salt of such ester, of such compound, or any other adduct or derivative which, upon administration to a patient, is capable of providing (directly or indirectly) a compound as otherwise described herein, or a metabolite or residue thereof. Pharmaceutically acceptable derivatives thus include among others pro-drugs. A pro-drug is a derivative of a compound, usually with significantly reduced pharmacological activity, which contains an additional moiety, which is susceptible to removal in vivo yielding the parent molecule as the pharmacologically active species. An example of a pro-drug is an ester, which is cleaved in vivo to yield a compound of interest. Pro-drugs of a variety of compounds, and materials and methods for derivatizing the parent compounds to create the pro-drugs, are known and may be adapted to the present invention. Pharmaceutically acceptable derivatives also include “reverse pro-drugs.” Reverse pro-drugs, rather than being activated, are inactivated upon absorption. For example, as discussed herein, many of the ester-containing compounds of the invention are biologically active but are inactivated upon exposure to certain physiological environments such as a blood, lymph, serum, extracellular fluid, etc. which contain esterase activity. The biological activity of reverse pro-drugs and pro-drugs may also be altered by appending a functionality onto the compound, which may be catalyzed by an enzyme. Also, included are oxidation and reduction reactions, including enzyme-catalyzed oxidation and reduction reactions. Certain exemplary pharmaceutical compositions and pharmaceutically acceptable derivatives will be discussed in more detail herein below.
[0036] The term “linker,” as used herein, refers to a chemical moiety utilized to attach one part of a compound of interest to another part of the compound. Exemplary linkers are described herein.
[0037] Unless indicated otherwise, the terms defined below have the following meanings:
[0038] “Compound”: The term “compound” or “chemical compound” as used herein can include organometallic compounds, organic compounds, metals, transitional metal complexes, and small molecules. In certain preferred embodiments, polynucleotides are excluded from the definition of compounds. In other preferred embodiments, polynucleotides and peptides are excluded from the definition of compounds. In a particularly preferred embodiment, the term compounds refers to small molecules (e.g., preferably, non-peptidic and non-oligomeric) and excludes peptides, polynucleotides, transition metal complexes, metals, and organometallic compounds.
[0039] “Small Molecule”: As used herein, the term “small molecule” refers to a non-peptidic, non-oligomeric organic compound either synthesized in the laboratory or found in nature. Small molecules, as used herein, can refer to compounds that are “natural product-like”, however, the term “small molecule” is not limited to “natural product-like” compounds. Rather, a small molecule is typically characterized in that it contains several carbon-carbon bonds, and has a molecular weight of less than 2000 g/mol, preferably less than 1500 g/mol, although this characterization is not intended to be limiting for the purposes of the present invention. Examples of “small molecules” that occur in nature include, but are not limited to, taxol, dynemicin, and rapamycin. Examples of “small molecules” that are synthesized in the laboratory include, but are not limited to, compounds described in Tan et al., (“Stereoselective Synthesis of over Two Million Compounds Having Structural Features Both Reminiscent of Natural Products and Compatible with Miniaturized Cell-Based Assays” J. Am. Chem. Soc. 120:8565, 1998; incorporated herein by reference). In certain other preferred embodiments, natural-product-like small molecules are utilized.
[0040] “Natural Product-Like Compound”: As used herein, the term “natural product-like compound” refers to compounds that are similar to complex natural products which nature has selected through evolution. Typically, these compounds contain one or more stereocenters, a high density and diversity of functionality, and a diverse selection of atoms within one structure. In this context, diversity of functionality can be defined as varying the topology, charge, size, hydrophilicity, hydrophobicity, and reactivity to name a few, of the functional groups present in the compounds. The term, “high density of functionality”, as used herein, can preferably be used to define any molecule that contains preferably three or more latent or active diversifiable functional moieties. These structural characteristics may additionally render the inventive compounds functionally reminiscent of complex natural products, in that they may interact specifically with a particular biological receptor, and thus may also be functionally natural product-like.
[0041] “Metal chelator”: As used herein, the term “metal chelator” refers to any molecule or moiety that is is capable of forming a complex (i.e., “chelates”) with a metal ion. In certain exemplary embodiments, a metal chelator refers to to any molecule or moiety that “binds” to a metal ion, in solution, making it unavailable for use in chemical/enzymatic reactions. In certain embodiments, the solution comprises aqueous environments under physiological conditions. Examples of metal ions include, but are not limited to, Ca 2+ , Fe 3+ , Zn 2+ , Na + , etc. In certain embodiments, the metal chelator binds Zn 2+ . In certain embodiments, molecules of moieties that precipitate metal ions are not considered to be metal chelators.
[0042] As used herein the term “biological sample” includes, without limitation, cell cultures or extracts thereof; biopsied material obtained from an animal (e.g., mammal) or extracts thereof; and blood, saliva, urine, feces, semen, tears, or other body fluids or extracts thereof. For example, the term “biological sample” refers to any solid or fluid sample obtained from, excreted by or secreted by any living organism, including single-celled micro-organisms (such as bacteria and yeasts) and multicellular organisms (such as plants and animals, for instance a vertebrate or a mammal, and in particular a healthy or apparently healthy human subject or a human patient affected by a condition or disease to be diagnosed or investigated). The biological sample can be in any form, including a solid material such as a tissue, cells, a cell pellet, a cell extract, cell homogenates, or cell fractions; or a biopsy, or a biological fluid. The biological fluid may be obtained from any site (e.g., blood, saliva (or a mouth wash containing buccal cells), tears, plasma, serum, urine, bile, cerebrospinal fluid, amniotic fluid, peritoneal fluid, and pleural fluid, or cells therefrom, aqueous or vitreous humor, or any bodily secretion), a transudate, an exudate (e.g. fluid obtained from an abscess or any other site of infection or inflammation), or fluid obtained from a joint (e.g. a normal joint or a joint affected by disease such as rheumatoid arthritis, osteoarthritis, gout or septic arthritis). The biological sample can be obtained from any organ or tissue (including a biopsy or autopsy specimen) or may comprise cells (whether primary cells or cultured cells) or medium conditioned by any cell, tissue or organ. Biological samples may also include sections of tissues such as frozen sections taken for histological purposes. Biological samples also include mixtures of biological molecules including proteins, lipids, carbohydrates and nucleic acids generated by partial or complete fractionation of cell or tissue homogenates. Although the sample is preferably taken from a human subject, biological samples may be from any animal, plant, bacteria, virus, yeast, etc. The term animal, as used herein, refers to humans as well as non-human animals, at any stage of development, including, for example, mammals, birds, reptiles, amphibians, fish, worms and single cells. Cell cultures and live tissue samples are considered to be pluralities of animals. In certain exemplary embodiments, the non-human animal is a mammal (e.g., a rodent, a mouse, a rat, a rabbit, a monkey, a dog, a cat, a sheep, cattle, a primate, or a pig). An animal may be a transgenic animal or a human clone. If desired, the biological sample may be subjected to preliminary processing, including preliminary separation techniques.
BRIEF DESCRIPTION OF THE DRAWING
[0043] FIG. 1 includes a table of esterases found in human and mouse plasma.
[0044] FIG. 2 shows the design of a reverse pro-drug version of SAHA-SAHP.
[0045] FIG. 3 illustrates the stability of SAHA (with an amide) in PBS.
[0046] FIG. 4 illustrates the stability of SAHA in serum.
[0047] FIG. 5 shows the stability of SAHP (ester instead of amdie) in PBS.
[0048] FIG. 6 shows the degradation of SAHP in serum. In less than 15 minutes, SAHP is completely degraded.
[0049] FIG. 7 shows a more detailed study of the degradation of SAHP in serum. In less than 2 minutes, SAHP is completely degraded into phenol and the corresponding carboxylic acid.
[0050] FIG. 8 shows the degradation of SAHP by human serum under various conditions.
[0051] FIG. 9 shows the degradation of SAHP by recombinant paraoxonase.
[0052] FIG. 10 shows the degradation of SAHP in RPMI media with 10% FBS.
[0053] FIG. 11 shows the effect of SAHA v. SAHP on lysine acetylation.
[0054] FIG. 12 shows the stability of SAHP in an olive oil/acetone formulation for murine model.
[0055] FIG. 13 is an exemplary synthetic scheme for preparing SAHP.
[0056] FIG. 14 . Interleukin-7 is a growth factor for T-cell development, in particular the gamma-delta subset. Transgenic mice overexpressing IL-7 in keratinocytes were developed by the laboratories of Thomas Kupper and Benjamin Rich, using a tissue-specific keratin-14 promoter element. These mice have been reported to develop a characteristic lymphoproliferative skin disease grossly and histologically similar to human cutaneous T-cell lymphoma (CTCL). Transformed lymphocytes derived from involved skin were passaged ex vivo and injected into syngeneic (non-transgenic) mice. After fourteen days, these mice develop a homogeneous lymphoproliferative disease. Two cohorts of five mice were included in a prospective study of topical, daily suberoyl hydroxamic acid phenyl ester (SAHP, also known as SHAPE) versus vehicle control. After fourteen days of therapy, mice were sacrificed and the treated region was dissected for histopathologic examination. In SHAPE-treated mice, hematoxylin-eosin staining demonstrates a marked reduction in lymphomatous infiltration within the treated window. Vehicle control mice failed to demonstrate a cytotoxic response.
[0057] FIG. 15 shows the pharmacodynamic effect of SAHP treatment as assessed using immunohistochemical staining for acetylated histones compared to vehicle treated controls. In SAHP-treated mice, AcH3K18 staining demonstrates hyperacetylated histone staining at the margin of compound treatment, with absent nuclear staining in the region of drug response. Vehicle control mice failed to demonstrate an increase in histone hyperacetylation.
DETAILED DESCRIPTION OF THE INVENTION
[0058] As discussed above, there remains a need for the development of novel histone deacetylase inhibitors. The present invention provides novel compounds of general formula (I), and methods for the synthesis thereof, which compounds are useful as inhibitors of histone deacetylases, and thus are useful for the treatment of proliferative diseases, particularly proliferative or other disorders associated with the skin and/or hair. In particular, the inventive compounds comprise an ester linkage. The ester linkage is preferably sensitive to esterase cleavage; therefore, when the compound is contacted with an esterase it is deactivated.
Compounds of the Invention
[0059] As discussed above, the present invention provides a novel class of compounds useful for the treatment of cancer and other proliferative conditions related thereto. In certain embodiments, the compounds of the present invention are useful as inhibitors of histone deacetylases and thus are useful as anticancer agents, and thus may be useful in the treatment of cancer, by effecting tumor cell death or inhibiting the growth of tumor cells. In certain exemplary embodiments, the inventive anticancer agents are useful in the treatment of cancers and other proliferative disorders, including, but not limited to breast cancer, cervical cancer, colon and rectal cancer, leukemia, lung cancer, melanoma, multiple myeloma, non-Hodgkin's lymphoma, ovarian cancer, pancreatic cancer, prostate cancer, and gastric cancer, to name a few. In certain embodiments, the inventive anticancer agents are active against leukemia cells and melanoma cells, and thus are useful for the treatment of leukemias (e.g., myeloid, lymphocytic, myelocytic and lymphoblastic leukemias) and malignant melanomas. In certain embodiments, the inventive compounds are active against cutaneous T-cell lymphoma. Additionally, as described above and in the exemplification, the inventive compounds may also be useful in the treatment of protozoal infections. In certain exemplary embodiments, the compounds of the invention are useful for disorders resulting from histone deacetylation activity. In certain embodiments, the compounds are useful for skin disorders. Exemplary skin disorders that may be treated using the inventive compounds include cutaneous T-cell lymphoma (CTCL), skin cancers (e.g., squamous cell carcinoma, basal cell carcinoma, malignant melanoma, etc.), psoriasis, hair loss, dermatitis, neurofibromatosis, disorders associated with skin hyperpigmentation, etc.
[0060] Compounds of this invention comprise those, as set forth above and described herein, and are illustrated in part by the various classes, subgenera and species disclosed elsewhere herein.
[0061] In general, the present invention provides compounds having the general structure (I):
[0000]
[0062] and pharmaceutically acceptable salts and derivatives thereof;
[0000] wherein
[0063] A comprises a functional group that inhibits histone deacetylase;
[0064] L is a linker moiety; and
[0065] Ar is a substituted or unsubstituted aryl or heteroaryl moiety; substituted or unsubstituted, branched or unbranched arylaliphatic or heteroarylaliphatic moiety; a substituted or unsubstituted cyclic or heterocyclic moiety; substituted or unsubstituted, branched or unbranched cyclicaliphatic or heterocyclicaliphatic moiety.
[0066] In certain embodiments, A comprises a metal chelating functional group. For example, A comprises a Zn 2+ chelating group. In certain embodiments, A comprises a functional group selected group consisting of:
[0000]
[0067] In certain embodiments, A comprises hydroxamic acid
[0000]
[0000] or a salt thereof. In other embodiments, A comprises the formula:
[0000]
[0068] In certain particular embodiments, A comprises the formula:
[0000]
[0069] In other embodiments, A comprises a carboxylic acid (—CO 2 H). In other embodiments, A comprises an o-aminoanilide
[0000]
[0000] In other embodiments, A comprises an o-hydroxyanilide
[0000]
[0000] In yet other embodiments, A comprises a thiol (—SH).
[0070] In certain embodiments, Ar is arylaliphatic. In other embodiments, Ar is heteroarylaliphatic. In certain embodiments, Ar is a substituted or unsubstituted aryl moiety. In certain embodiments, Ar is a monocyclic, substituted or unsubstituted aryl moiety, preferably a five- or six-membered aryl moiety. In other embodiments, Ar is a bicyclic, substituted or unsubstituted aryl moiety. In still other embodiments, Ar is a tricyclic, substituted or unsubstituted aryl moiety. In certain embodiments, Ar is a substituted or unsubstituted phenyl moiety. In certain embodiments, Ar is an unsubstituted phenyl moiety. In other embodiments, Ar is a substituted phenyl moiety. In certain embodiments, Ar is a monosubstituted phenyl moiety. In certain particular embodiments, Ar is an ortho-substituted Ar moiety. In certain particular embodiments, Ar is an meta-substituted Ar moiety. In certain particular embodiments, Ar is an para-substituted Ar moiety. In certain embodiments, Ar is a disubstituted phenyl moiety. In certain embodiments, Ar is a trisubstituted phenyl moiety. In certain embodiments, Ar is a tetrasubstituted phenyl moiety. In certain embodiments, Ar is a substituted or unsubstituted cyclic or heterocyclic.
[0071] In certain embodiments, Ar is a substituted or unsubstituted heteroaryl moiety. In certain embodiments, Ar is a monocyclic, substituted or unsubstituted heteroaryl moiety, preferably a five- or six-membered heteroaryl moiety. In other embodiments, Ar is a bicyclic, substituted or unsubstituted heteroaryl moiety. In still other embodiments, Ar is a tricyclic, substituted or unsubstituted heteroaryl moiety. In certain embodiments, Ar comprises N, S, or O. In certain embodiments, Ar comprises at least one N. In certain embodiments, Ar comprises at least two N.
[0072] In certain embodiments, Ar is:
[0000]
[0000] wherein
[0073] n is an integer between 1 and 5, inclusive; preferably, between 1 and 3, inclusive; more preferably, 1 or 2;
[0074] R 1 is is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR A ; —C(═O)R A ; —CO 2 R A ; —CN; —SCN; —SR A ; —SOR A ; —SO 2 R A ; —NO 2 ; —N(R A ) 2 ; —NHR A ; —NHC(O)R A ; or —C(R A ) 3 ; wherein each occurrence of R A is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety. In certain embodiments, Ar is
[0000]
[0000] In other embodiments, Ar is
[0000]
[0000] In yet other embodiments, Ar is
[0000]
[0000] In certain embodiments, R 1 is —N(R A ) 2 , wherein R A is hydrogen or C 1 -C 6 alkyl. In certain embodiments, R 1 is —OR A , wherein R A is hydrogen or C 1 -C 6 alkyl. In certain particular embodiments, R 1 is —OMe. In certain embodiments, R 1 is branched or unbranched acyl. In certain embodiments, R 1 is —O(═O)OR A . In certain embodiments, R 1 is —C(═O)OR A , wherein R A is hydrogen or C 1 -C 6 alkyl. In certain embodiments, R 1 is —C(═O)NH 2 . In certain embodiments, R 1 is —NHC(═O)R A . In certain embodiments, R 1 is —NHC(═O)R A , wherein R A is hydrogen or C 1 -C 6 alkyl. In certain embodiments, R 1 is halogen. In certain embodiments, R 1 is C 1 -C 6 alkyl.
[0075] In certain particular embodiments, Ar is a substituted phenyl moiety of formula:
[0000]
[0076] In certain embodiments, Ar is chosen from one of the following:
[0000]
[0000] wherein
[0077] n is an integer between 1 and 4, inclusive; preferably, between 1 and 3, inclusive; more preferably, 1 or 2;
[0078] R 1 is is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR A ; —C(═O)R A ; —CO 2 R A ; —CN; —SCN; —SR A ; —SOR A ; —SO 2 R A ; —NO 2 ; —N(R A ) 2 ; —NHR A ; —NHC(O)R A ; or —C(R A ) 3 ; wherein each occurrence of R A is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety.
[0079] In certain embodiments, Ar is chosen from one of the following:
[0000]
[0000] Any of the above bicyclic ring system may be substituted with up to seven R 1 substituents as defined above.
[0080] In certain embodiments, L is a substituted or unsubstituted, cyclic or acyclic, branched or unbranched aliphatic moiety; a substituted or unsubstituted, cyclic or acyclic, branched or unbranched heteroaliphatic moiety; a substituted or unsubstituted aryl moiety; a substituted or unsubstituted heteroaryl moiety. In certain embodiments, L is a substituted or unsubstituted, cyclic or acyclic, branched or unbranched aliphatic moiety. In certain embodiments, L is C 1 -C 20 alkylidene, preferably C 1 to C 12 alkylidene, more preferably C 4 -C 7 alkylidene. In certain embodiments, L is C 1 -C 20 alkenylidene, preferably C 1 to C 12 alkenylidene, more preferably C 4 -C 7 alkenylidene. In certain embodiments, L is C 1 -C 20 alkynylidene, preferably C 1 to C 12 alkynylidene, more preferably C 4 -C 7 alkynylidene. In certain embodiments, L is a a substituted or unsubstituted, cyclic or acyclic, branched or unbranched heteroaliphatic moiety. In certain embodiments, L comprises a cyclic ring system, wherein the rings may be aryl, heteroaryl, non-aromatic carbocyclic, or non-aromatic heterocyclic. In still other embodiments, L comprises a substituted or unsubstituted heteroaryl moiety. In certain particular embodiments, L comprises a phenyl ring. In certain embodiments, L comprises multiple phenyl rings (e.g., one, two, three, or four phenyl rings).
[0081] In certain embodiments, L is
[0000]
[0000] wherein n is an integer between 1 and 4, inclusive; preferably, between 1 and 3, inclusive; more preferably, 1 or 2; and R 1 is is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR A ; —C(═O)R A ; —CO 2 R A ; —CN; —SCN; —SR A ; —SOR A ; —SO 2 R A ; —NO 2 ; —N(R A ) 2 ; —NHR A ; —NHC(O)R A ; or —C(R A ) 3 ; wherein each occurrence of R A is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety. In certain embodiments, L is
[0000]
[0082] In certain embodiments, L is
[0000]
[0083] In certain embodiments, L is an unbranched, unsubstituted, acyclic alkyl chain. In certain embodiments, L is
[0000]
[0000] In other embodiments, L is
[0000]
[0000] In certain other embodiments, L is
[0000]
[0000] In other embodiments, L is
[0000]
[0000] In yet other embodiments, L is
[0000]
[0084] In certain embodiments, L is a substituted, acyclic aliphatic chain. In certain embodiments, L is
[0000]
[0085] In certain embodiments, L is an unbranched, unsubstituted, acyclic heteroaliphatic chain. In certain particular embodiments, L is
[0000]
[0000] wherein n is an integer between 0 and 10, inclusive; preferably, between 0 and 5, inclusive; and m is an integer between 0 and 10, inclusive; preferably, between 0 and 5, inclusive. In certain particular embodiments, L is
[0000]
[0000] wherein n is an integer between 0 and 10, inclusive; preferably, between 0 and 5, inclusive; and m is an integer between 0 and 10, inclusive; preferably, between 0 and 5, inclusive. In certain particular embodiments, L is
[0000]
[0000] wherein n is an integer between 0 and 10, inclusive; preferably, between 0 and 5, inclusive; m is an integer between 0 and 10, inclusive; preferably, between 0 and 5, inclusive; and R′ is hydrogen, C 1 -C 6 aliphatic, heteroaliphatic, aryl, heteroaryl, or acyl. In certain particular embodiments, L is
[0000]
[0000] wherein n is an integer between 0 and 10, inclusive; preferably, between 0 and 5, inclusive; and m is an integer between 0 and 10, inclusive; preferably, between 0 and 5, inclusive.
[0086] In certain embodiments of the invention, compounds of formula (I) have the following structure as shown in formula (Ia):
[0000]
[0000] wherein
[0087] n is an integer between 0 and 15, inclusive; preferably, between 0 and 10, inclusive; more preferably, between 1 and 8, inclusive; even more preferably, 4, 5, 6, 7, or 8; and
[0088] Ar is defined as above. In certain embodiments, n is 5. In other embodiments, n is 6. In still other embodiments, n is 7.
[0089] In certain embodiments of the invention, compounds of formula (I) have the following structure as shown in formula (Ib):
[0000]
[0000] wherein
[0090] n is an integer between 0 and 15, inclusive; preferably, between 0 and 10, inclusive; more preferably, between 1 and 8, inclusive; even more preferably, 4, 5, 6, 7, or 8;
[0091] m is an integer between 1 and 5, inclusive; preferably, m is 1, 2, or 3; and
[0092] R 1 is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR A ; —C(═O)R A ; —CO 2 R A ; —CN; —SCN; —SR A ; —SOR A ; —SO 2 R A ; —NO 2 ; —N(R A ) 2 ; —NHC(O)R A ; or —C(R A ) 3 ; wherein each occurrence of R A is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety. In certain embodiments, R 1 is hydrogen, halogen, hydroxy, amino, alkylamino, dialkylamino, nitroso, acyl, or C 1 -C 6 alkyl. In certain embodiments, R 1 is aryl. In certain embodiments, R 1 is a multicyclic aryl moiety. In other embodiments, R 1 is heteroaryl. In certain embodiments, R 1 is carbocyclic. In other embodiments, R 1 is heterocyclic. In certain embodiments R 1 comprises a 1,3-dioxane ring optionally substituted. In certain embodiments, n is 5. In other embodiments, n is 6. In still other embodiments, n is 7. In certain embodiments, m is 0. In other embodiments, m is 1. In still other embodiments, m is 2.
[0093] In certain embodiments of the invention, compounds of formula (I) are of the formula (Ic):
[0000]
[0000] wherein
[0094] n is an integer between 0 and 15, inclusive; preferably, between 0 and 10, inclusive; more preferably, between 1 and 8, inclusive; even more preferably, 4, 5, 6, 7, or 8; and
[0095] R 1 is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR A ; —C(═O)R A ; —CO 2 R A ; —CN; —SCN; —SR A ; —SOR A ; —SO 2 R A ; —NO 2 ; —N(R A ) 2 ; —NHC(O)R A ; or —C(R A ) 3 ; wherein each occurrence of R A is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety. In certain embodiments, R 1 is hydrogen, halogen, hydroxy, amino, alkylamino, dialkylamino, nitroso, acyl, or C 1 -C 6 alkyl. In certain embodiments, R 1 is aryl. In other embodiments, R 1 is heteroaryl. In certain embodiments, R 1 is carbocyclic. In other embodiments, R 1 is heterocyclic. In certain embodiments, n is 5. In other embodiments, n is 6. In still other embodiments, n is 7.
[0096] In certain embodiments of the invention, compounds of formula (I) are of the formula (Id):
[0000]
[0000] wherein
[0097] n is an integer between 1 and 5, inclusive; preferably, between 1 and 3; more preferably, 1 or 2; and
[0098] R 1 is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR A ; —C(═O)R A ; —CO 2 R A ; —CN; —SCN; —SR A ; —SOR A ; —SO 2 R A ; —NO 2 ; —N(R A ) 2 ; —NHC(O)R A ; or —C(R A ) 3 ; wherein each occurrence of R A is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety. In certain embodiments, R 1 is hydrogen, halogen, hydroxy, amino, alkylamino, dialkylamino, nitroso, acyl, or C 1 -C 6 alkyl. In certain embodiments, R 1 is aryl. In other embodiments, R 1 is heteroaryl. In certain embodiments, R 1 is carbocyclic. In other embodiments, R 1 is heterocyclic. In certain embodiments, n is 1. In other embodiments, n is 2.
[0099] In certain embodiments of the invention, compounds of formula (I) are of the formula (Ie):
[0000]
[0000] wherein R1 is defined as above.
[0100] In certain embodiments of the invention, compounds of formula (I) have the following stereochemistry and structure as shown in formula (If):
[0000]
[0000] wherein A, L and Ar are defined as above; and
[0101] n is an integer between 0 and 10, inclusive; preferably, between 0 and 5, inclusive; even more preferably, 0, 1, 2, or 3. In certain embodiments, Ar is phenyl.
[0102] In certain embodiments, compounds of formula (I) are of the formula (Ig):
[0000]
[0000] wherein
[0103] A and L are defined as above;
[0104] R 2 is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR B ; —C(═O)R B ; —CO 2 R B ; —CN; —SCN; —SR B ; —SOR B ; —SO 2 R B ; —NO 2 ; —N(R B ) 2 ; —NHC(O)R B ; or —C(R B ) 3 ; wherein each occurrence of R B is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety; and
[0105] R 3 is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR C ; —C(═O)R C ; —CO 2 R C ; —CN; —SCN; —SR C ; —SOR C ; —SO 2 R C ; —NO 2 ; —N(R C ) 2 ; —NHC(O)R C ; or —C(R C ) 3 ; wherein each occurrence of R C is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety.
[0106] In certain embodiments, R 2 is hydrogen. In other embodiments, R 2 is hydroxyl or a protected hydroxyl group. In certain embodiments, R 2 is alkoxy. In yet other embodiments, R 2 is a lower alkyl, alkenyl, or alkynyl group. In certain embodiments, R 2 is —CH 2 —X(R B ) n , wherein X is O, S, N, or C, preferably O, S, or N; and n is 1, 2, or 3. In certain embodiments, R 2 is —CH 2 —OR B . In other embodiments, R 2 is —CH 2 —SR B . In yet other embodiments, R 2 is —CH 2 —R B . In other embodiments, R 2 is —CH 2 —N(R B ) 2 . In still other embodiments, R 2 is —CH 2 —NHR B . In certain embodiments of the invention, R B is one of:
[0000]
[0107] wherein m and p are each independently integers from 0 to 3; q 1 is an integer from 1 to 6; R 2C is hydrogen, lower alkyl or a nitrogen protecting group; and each occurrence of R 2B is independently hydrogen, halogen, —CN, or WR W1 wherein W is O, S, NR W2 , —C(═O), —S(═O), —SO 2 , —C(═O)O—, —OC(═O), —C(═O)NR W2 , —NR W2 C(═O); wherein each occurrence of R W1 and R W2 is independently hydrogen, a protecting group, a prodrug moiety or an alkyl, cycloalkyl, heteroalkyl, heterocyclic, aryl or heteroaryl moiety, or, when W is NR W2 , R W1 and R W2 , taken together with the nitrogen atom to which they are attached, form a heterocyclic or heteroaryl moiety; or any two adjacent occurrences of R 2B , taken together with the atoms to which they are attached, form a substituted or unsubstituted, saturated or unsaturated alicyclic or heterocyclic moiety, or a substituted or unsubstituted aryl or heteroaryl moiety. In certain embodiments of the invention, R B is one of the structures:
[0000]
[0000] wherein m is an integer from 1 to 4; R 2C is hydrogen, lower alkyl or a nitrogen protecting group; and each occurrence of R 2B is independently hydrogen, halogen, —CN, or WR W1 wherein W is O, S, NR W2 , —C(═O), —S(═O), —SO 2 , —C(═O)O—, —OC(═O), —C(═O)NR W2 , —NR W2 C(═O); wherein each occurrence of R W1 and R W2 is independently hydrogen, a protecting group, a prodrug moiety or an alkyl, cycloalkyl, heteroalkyl, heterocyclic, aryl or heteroaryl moiety, or, when W is NR W2 , R W1 and R W2 , taken together with the nitrogen atom to which they are attached, form a heterocyclic or heteroaryl moiety; or any two adjacent occurrences of R 2B , taken together with the atoms to which they are attached, form a substituted or unsubstituted, saturated or unsaturated alicyclic or heterocyclic moiety, or a substituted or unsubstituted aryl or heteroaryl moiety.
[0108] In certain embodiments, —X(R B ) n has one of the structures:
[0000]
[0109] In certain embodiments, R 2 is
[0000]
[0000] wherein X is N and Y is NH, S, or O. In other embodiments, R 2 is
[0000]
[0110] In certain embodiments, R 3 is substituted or unsubstituted aryl. In certain embodiments, R 3 is substituted or unsubstituted phenyl. In certain particular embodiments, R 3 is monosubstituted phenyl. In certain embodiments, R 3 is para-substituted phenyl. In certain embodiments, R 3 is
[0000]
[0000] wherein R 3 ′ is hydrogen, a protecting group, a solid support unit, an alkyl, acyl, cycloalkyl, heteroalkyl, heterocyclic, aryl, heteroaryl, -(alkyl)aryl, -(alkyl)heteroaryl, -(heteroalkyl)aryl, or -(heteroalkyl)heteroaryl moiety. In certain embodiments, R 3 is
[0000]
[0000] In other embodiments, R 3 is substituted or unsubstituted heteroaryl.
[0111] In certain embodiments, the stereochemistry of formula (Ig) is defined as follows:
[0000]
[0112] In certain embodiments of the invention, compounds of formula (I) are of the formula (Ih):
[0000]
[0000] wherein
[0113] A and L are defined as above;
[0114] n is an integer between 0 and 10, inclusive; preferably, between 1 and 6, inclusive; more preferably, between 1 and 3, inclusive; and even more preferably, 0, 1, 2, or 3;
[0115] R 2 is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR B ; —C(═O)R B ; —CO 2 R B ; —CN; —SCN; —SR B ; —SOR B ; —SO 2 R B ; —NO 2 ; —N(R B ) 2 ; —NHC(O)R B ; or —C(R B ) 3 ; wherein each occurrence of R B is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety; and
[0116] R 3 is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR C ; —C(═O)R C ; —CO 2 R C ; —CN; —SCN; —SR C ; —SOR C ; —SO 2 R C ; —NO 2 ; —N(R C ) 2 ; —NHC(O)R C ; or —C(R C ) 3 ; wherein each occurrence of R C is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety.
[0117] In certain embodiments, R 2 is hydrogen. In other embodiments, R 2 is hydroxyl or a protected hydroxyl group. In certain embodiments, R 2 is alkoxy. In yet other embodiments, R 2 is a lower alkyl, alkenyl, or alkynyl group. In certain embodiments, R 2 is —CH 2 —X(R B ) n ; wherein X is O, S, N, or C, preferably O, S, or N; and n is 1, 2, or 3. In certain embodiments, R 2 is —CH 2 —OR B . In other embodiments, R 2 is —CH 2 —SR B . In yet other embodiments, R 2 is —CH 2 —R B . In other embodiments, R 2 is —CH 2 —N(R B ) 2 . In still other embodiments, R 2 is —CH 2 —NHR B . In certain embodiments of the invention, R B is one of:
[0000]
[0118] wherein m and p are each independently integers from 0 to 3; q 1 is an integer from 1 to 6; R 2C is hydrogen, lower alkyl or a nitrogen protecting group; and each occurrence of R 2B is independently hydrogen, halogen, —CN, or WR W1 wherein W is O, S, NR W2 , —C(═O), —S(═O), —SO 2 , —C(═O)O—, —OC(═O), —C(═O)NR W2 , —NR W2 C(═O); wherein each occurrence of R W1 and R W2 is independently hydrogen, a protecting group, a prodrug moiety or an alkyl, cycloalkyl, heteroalkyl, heterocyclic, aryl or heteroaryl moiety, or, when W is NR W2 , R W1 and R W2 , taken together with the nitrogen atom to which they are attached, form a heterocyclic or heteroaryl moiety; or any two adjacent occurrences of R 2B , taken together with the atoms to which they are attached, form a substituted or unsubstituted, saturated or unsaturated alicyclic or heterocyclic moiety, or a substituted or unsubstituted aryl or heteroaryl moiety. In certain embodiments of the invention, R B is one of the structures:
[0000]
[0000] wherein m is an integer from 1 to 4; R is hydrogen, lower alkyl or a nitrogen protecting group; and each occurrence of R 2B is independently hydrogen, halogen, —CN, or WR W1 wherein W is O, S, NR W2 , —C(═O), —S(═O), —SO 2 , —C(═O)O—, —OC(═O), —C(═O)NR W2 , —NR W2 C(═O); wherein each occurrence of R W1 and R W2 is independently hydrogen, a protecting group, a prodrug moiety or an alkyl, cycloalkyl, heteroalkyl, heterocyclic, aryl or heteroaryl moiety, or, when W is NR W2 , R W1 and R W2 , taken together with the nitrogen atom to which they are attached, form a heterocyclic or heteroaryl moiety; or any two adjacent occurrences of R 2B , taken together with the atoms to which they are attached, form a substituted or unsubstituted, saturated or unsaturated alicyclic or heterocyclic moiety, or a substituted or unsubstituted aryl or heteroaryl moiety.
[0119] In certain embodiments, —X(R B ) n has one of the structures:
[0000]
[0120] In certain embodiments, R 2 is
[0000]
[0000] wherein X is N and Y is NH, S, or O. In other embodiments, R 2 is
[0000]
[0121] In certain embodiments, R 3 is substituted or unsubstituted aryl. In certain embodiments, R 3 is substituted or unsubstituted phenyl. In certain particular embodiments, R 3 is monosubstituted phenyl. In certain embodiments, R 3 is para-substituted phenyl. In certain embodiments, R 3 is
[0000]
[0000] wherein R 3 ′ is hydrogen, a protecting group, a solid support unit, an alkyl, acyl, cycloalkyl, heteroalkyl, heterocyclic, aryl, heteroaryl, -(alkyl)aryl, -(alkyl)heteroaryl, -(heteroalkyl)aryl, or -(heteroalkyl)heteroaryl moiety. In certain embodiments, R 3 is
[0000]
[0000] In other embodiments, R 3 is substituted or unsubstituted heteroaryl.
[0122] In certain embodiments, the stereochemistry of formula (Ih) is defined as follows:
[0000]
[0123] In certain embodiments of the invention, compounds of formula (I) have structure as shown in formula (Ii):
[0000]
[0000] wherein
[0124] A and L are defined as above;
[0125] R 2 is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR B ; —C(═O)R B ; —CO 2 R B ; —CN; —SCN; —SR B ; —SOR B ; —SO 2 R B ; —NO 2 ; —N(R B ) 2 ; —NHC(O)R B ; or —C(R B ) 3 ; wherein each occurrence of R B is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety; and
[0126] R 3 is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR C ; —C(═O)R C ; —CO 2 R C ; —CN; —SCN; —SR C ; —SOR C ; —SO 2 R C ; —NO 2 ; —N(R C ) 2 ; —NHC(O)R C ; or —C(R C ) 3 ; wherein each occurrence of R C is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety.
[0127] In certain embodiments, R 2 is hydrogen. In other embodiments, R 2 is hydroxyl or a protected hydroxyl group. In certain embodiments, R 2 is alkoxy. In yet other embodiments, R 2 is a lower alkyl, alkenyl, or alkynyl group. In certain embodiments, R 2 is —CH 2 —X(R B ) n , wherein X is O, S, N, or C, preferably O, S, or N; and n is 1, 2, or 3. In certain embodiments, R 2 is —CH 2 —OR B . In other embodiments, R 2 is —CH 2 —SR B . In yet other embodiments, R 2 is —CH 2 —R B . In other embodiments, R 2 is —CH 2 —N(R B ) 2 . In still other embodiments, R 2 is —CH 2 —NHR B . In certain embodiments of the invention, R B is one of:
[0000]
[0128] wherein m and p are each independently integers from 0 to 3; q 1 is an integer from 1 to 6; R 2C is hydrogen, lower alkyl or a nitrogen protecting group; and each occurrence of R 2B is independently hydrogen, halogen, —CN, or WR W1 wherein W is O, S, NR W2 , —C(═O), —S(═O), —SO 2 , —C(═O)O—, —OC(═O), —C(═O)NR W2 , —NR W2 C(═O); wherein each occurrence of R W1 and R W2 is independently hydrogen, a protecting group, a prodrug moiety or an alkyl, cycloalkyl, heteroalkyl, heterocyclic, aryl or heteroaryl moiety, or, when W is NR W2 , R W1 and R W2 , taken together with the nitrogen atom to which they are attached, form a heterocyclic or heteroaryl moiety; or any two adjacent occurrences of R 2B , taken together with the atoms to which they are attached, form a substituted or unsubstituted, saturated or unsaturated alicyclic or heterocyclic moiety, or a substituted or unsubstituted aryl or heteroaryl moiety. In certain embodiments of the invention, R B is one of the structures:
[0000]
[0000] wherein m is an integer from 1 to 4; R 2C is hydrogen, lower alkyl or a nitrogen protecting group; and each occurrence of R 2B is independently hydrogen, halogen, —CN, or WR W1 wherein W is O, S, NR W2 , —C(═O), —S(═O), —SO 2 , —C(═O)O—, —OC(═O), —C(═O)NR W2 , —NR W2 C(═O); wherein each occurrence of R W1 and R W2 is independently hydrogen, a protecting group, a prodrug moiety or an alkyl, cycloalkyl, heteroalkyl, heterocyclic, aryl or heteroaryl moiety, or, when W is NR W2 , R W1 and R W2 , taken together with the nitrogen atom to which they are attached, form a heterocyclic or heteroaryl moiety; or any two adjacent occurrences of R 2B , taken together with the atoms to which they are attached, form a substituted or unsubstituted, saturated or unsaturated alicyclic or heterocyclic moiety, or a substituted or unsubstituted aryl or heteroaryl moiety.
[0129] In certain embodiments, —X(R B ) n has one of the structures:
[0000]
[0130] In certain embodiments, R 2 is
[0000]
[0000] wherein X is N and Y is NH, S, or O. In other embodiments, R 2 is
[0000]
[0131] In certain embodiments, R 3 is substituted or unsubstituted aryl. In certain embodiments, R 3 is substituted or unsubstituted phenyl. In certain particular embodiments, R 3 is monosubstituted phenyl. In certain embodiments, R 3 is para-substituted phenyl. In certain embodiments, R 3 is
[0000]
[0000] wherein R 3 ′ is hydrogen, a protecting group, a solid support unit, an alkyl, acyl, cycloalkyl, heteroalkyl, heterocyclic, aryl, heteroaryl, -(alkyl)aryl, -(alkyl)heteroaryl, -(heteroalkyl)aryl, or -(heteroalkyl)heteroaryl moiety. In certain embodiments, R 3 is
[0000]
[0000] In other embodiments, R 3 is substituted or unsubstituted heteroaryl.
[0132] In certain embodiments, the stereochemistry of formula (Ii) is defined as follows:
[0000]
[0133] In certain embodiments of the invention, compounds of formula (I) have the following stereochemistry and structure as shown in formula (Ij):
[0000]
[0000] wherein
[0134] R 2 is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR B ; —C(═O)R B ; —CO 2 R B ; —CN; —SCN; —SR B ; —SOR B ; —SO 2 R B ; —NO 2 ; —N(R B ) 2 ; —NHC(O)R B ; or —C(R B ) 3 ; wherein each occurrence of R B is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety; and
[0135] R 3 is hydrogen; halogen; cyclic or acyclic, substituted or unsubstituted, branched or unbranched aliphatic; cyclic or acyclic, substituted or unsubstituted, branched or unbranched heteroaliphatic; substituted or unsubstituted, branched or unbranched acyl; substituted or unsubstituted, branched or unbranched aryl; substituted or unsubstituted, branched or unbranched heteroaryl; —OR C ; —C(═O)R C ; —CO 2 R C ; —CN; —SCN; —SR C ; —SOR C ; —SO 2 R C ; —NO 2 ; —N(R C ) 2 ; —NHC(O)R C ; or —C(R C ) 3 ; wherein each occurrence of R C is independently a hydrogen, a protecting group, an aliphatic moiety, a heteroaliphatic moiety, an acyl moiety; an aryl moiety; a heteroaryl moiety; alkoxy; aryloxy; alkylthio; arylthio; amino, alkylamino, dialkylamino, heteroaryloxy; or heteroarylthio moiety.
[0136] In certain embodiments, R 2 is hydrogen. In other embodiments, R 2 is hydroxyl or a protected hydroxyl group. In certain embodiments, R 2 is alkoxy. In yet other embodiments, R 2 is a lower alkyl, alkenyl, or alkynyl group. In certain embodiments, R 2 is —CH 2 —X(R B ) n ; wherein X is O, S, N, or C, preferably O, S, or N; and n is 1, 2, or 3. In certain embodiments, R 2 is —CH 2 —OR B . In other embodiments, R 2 is —CH 2 —SR B . In yet other embodiments, R 2 is —CH 2 —R B . In other embodiments, R 2 is —CH 2 —N(R B ) 2 . In still other embodiments, R 2 is —CH 2 —NHR B . In certain embodiments of the invention, R B is one of:
[0000]
[0137] wherein m and p are each independently integers from 0 to 3; q 1 is an integer from 1 to 6; R 2C is hydrogen, lower alkyl or a nitrogen protecting group; and each occurrence of R 2B is independently hydrogen, halogen, —CN, or WR W1 wherein W is O, S, NR W2 , —C(═O), —S(═O), —SO 2 , —C(═O)O—, —OC(═O), —C(═O)NR W2 , —NR W2 C(═O); wherein each occurrence of R W1 and R W2 is independently hydrogen, a protecting group, a prodrug moiety or an alkyl, cycloalkyl, heteroalkyl, heterocyclic, aryl or heteroaryl moiety, or, when W is NR W2 , R W1 and R W2 , taken together with the nitrogen atom to which they are attached, form a heterocyclic or heteroaryl moiety; or any two adjacent occurrences of R 2B , taken together with the atoms to which they are attached, form a substituted or unsubstituted, saturated or unsaturated alicyclic or heterocyclic moiety, or a substituted or unsubstituted aryl or heteroaryl moiety. In certain embodiments of the invention, R B is one of the structures:
[0000]
[0000] wherein m is an integer from 1 to 4; R 2C is hydrogen, lower alkyl or a nitrogen protecting group; and each occurrence of R 2B is independently hydrogen, halogen, —CN, or WR W1 wherein W is O, S, NR W2 , —C(═O), —S(═O), —SO 2 , —C(═O)O—, —OC(═O), —C(═O)NR W2 , —NR W2 C(═O); wherein each occurrence of R W1 and R W2 is independently hydrogen, a protecting group, a prodrug moiety or an alkyl, cycloalkyl, heteroalkyl, heterocyclic, aryl or heteroaryl moiety, or, when W is NR W2 , R W1 and R W2 , taken together with the nitrogen atom to which they are attached, form a heterocyclic or heteroaryl moiety; or any two adjacent occurrences of R 2B , taken together with the atoms to which they are attached, form a substituted or unsubstituted, saturated or unsaturated alicyclic or heterocyclic moiety, or a substituted or unsubstituted aryl or heteroaryl moiety.
[0138] In certain embodiments, —X(R B ) n has one of the structures:
[0000]
[0139] In certain embodiments, R 2 is
[0000]
[0000] wherein X is N and Y is NH, S, or O. In other embodiments, R 2 is
[0000]
[0140] In certain embodiments, R 3 is substituted or unsubstituted aryl. In certain embodiments, R 3 is substituted or unsubstituted phenyl. In certain particular embodiments, R 3 is monosubstituted phenyl. In certain embodiments, R 3 is para-substituted phenyl. In certain embodiments, R 3 is
[0000]
[0000] wherein R 3 ′ is hydrogen, a protecting group, a solid support unit, an alkyl, acyl, cycloalkyl, heteroalkyl, heterocyclic, aryl, heteroaryl, -(alkyl)aryl, -(alkyl)heteroaryl, -(heteroalkyl)aryl, or -(heteroalkyl)heteroaryl moiety. In certain embodiments, R 3 is
[0000]
[0000] In other embodiments, R 3 is substituted or unsubstituted heteroaryl.
[0141] Another class of compounds of special interest includes those compounds of the invention as described above and in certain subclasses herein, wherein R 3 is a substituted phenyl moiety and the compounds have the formula (II):
[0000]
[0000] wherein
[0142] L, A, X, and R B are defined as above;
[0143] n is an integer between 0 and 5, inclusive; preferably, between, 1 and 3; more preferably, 2; and
[0144] Z is hydrogen, —(CH 2 ) q OR Z , —(CH 2 ) q SR Z , —(CH 2 ) q N(R Z ) 2 , —C(═O)R Z , —C(═O)N(R Z ) 2 , or an alkyl, heteroalkyl, aryl, heteroaryl, -(alkyl)aryl, -(alkyl)heteroaryl, -(heteroalkyl)aryl, or -(heteroalkyl)heteroaryl moiety, wherein q is 0-4, and wherein each occurrence of R Z is independently hydrogen, a protecting group, a solid support unit, or an alkyl, acyl, cycloalkyl, heteroalkyl, heterocyclic, aryl, heteroaryl, -(alkyl)aryl, -(alkyl)heteroaryl, -(heteroalkyl)aryl, or -(heteroalkyl)heteroaryl moiety. In certain embodiments, R Z is hydrogen. In other embodiments, R Z is C 1 -C 6 alkyl. In certain embodiments, R Z is an oxygen-protecting group.
[0145] Another class of compounds includes those compounds of formula (II), wherein Z is —CH 2 OR Z , and the compounds have the general structure (Im):
[0000]
[0000] wherein
[0146] R B , R Z , X, L, n, and A are defined generally above and in classes and subclasses herein. In certain embodiments, X is S. In other embodiments, X is O.
[0147] Yet another class of compounds of particular interest includes those compounds of formula (Ii), wherein X is S and the compounds have the general structure (In):
[0000]
[0000] wherein
[0148] R B , X, L, n, and A are defined as above; and
[0149] R Z is as defined generally above and in classes and subclasses herein.
[0150] Yet another class of compounds of special interest includes those compounds of formula (Ii), wherein X is —NR 2A and the compounds have the general structure (Io):
[0000]
[0000] wherein
[0151] R B , R Z , X, L, n, and A are defined generally above and in classes and subclasses herein.
[0152] Yet another class of compounds of special interest includes those compounds of formula (Ii), wherein X is O and the compounds have the general structure (Ip):
[0000]
[0000] wherein
[0153] R B , R Z , X, L, n, and A are defined generally above and in classes and subclasses herein.
[0154] Exemplary compounds of the invention are shown:
[0000]
[0155] Some of the foregoing compounds can comprise one or more asymmetric centers, and thus can exist in various isomeric forms, e.g., stereoisomers and/or diastereomers. Thus, inventive compounds and pharmaceutical compositions thereof may be in the form of an individual enantiomer, diastereomer or geometric isomer, or may be in the form of a mixture of stereoisomers. In certain embodiments, the compounds of the invention are enantiopure compounds. In certain other embodiments, mixtures of stereoisomers or diastereomers are provided.
[0156] Furthermore, certain compounds, as described herein may have one or more double bonds that can exist as either the Z or E isomer, unless otherwise indicated. The invention additionally encompasses the compounds as individual isomers substantially free of other isomers and alternatively, as mixtures of various isomers, e.g., racemic mixtures of stereoisomers. In addition to the above-mentioned compounds per se, this invention also encompasses pharmaceutically acceptable derivatives of these compounds and compositions comprising one or more compounds of the invention and one or more pharmaceutically acceptable excipients or additives.
[0157] Compounds of the invention may be prepared by crystallization of the compound under different conditions and may exist as one or a combination of polymorphs of the compound forming part of this invention. For example, different polymorphs may be identified and/or prepared using different solvents, or different mixtures of solvents for recrystallization; by performing crystallizations at different temperatures; or by using various modes of cooling, ranging from very fast to very slow cooling during crystallizations. Polymorphs may also be obtained by heating or melting the compound followed by gradual or fast cooling. The presence of polymorphs may be determined by solid probe NMR spectroscopy, IR spectroscopy, differential scanning calorimetry, powder X-ray diffractogram and/or other techniques. Thus, the present invention encompasses inventive compounds, their derivatives, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts their pharmaceutically acceptable solvates and pharmaceutically acceptable compositions containing them.
Synthetic Overview
[0158] The synthesis of the various monomeric compounds used to prepare the dimeric, multimeric, and polymeric compounds of the invention are known in the art. These published syntheses may be utilized to prepare the compounds of the invention. Exemplary synthetic methods for preparing compounds of the invention are described in U.S. Pat. No. 6,960,685; U.S. Pat. No. 6,897,220; U.S. Pat. No. 6,541,661; U.S. Pat. No. 6,512,123; U.S. Pat. No. 6,495,719; US 2006/0020131; US 2004/087631; US 2004/127522; US 2004/0072849; US 2003/0187027; WO 2005/018578; WO 2005/007091; WO 2005/007091; WO 2005/018578; WO 2004/046104; WO 2002/89782; each of which is incorporated herein by reference. In many cases, an amide moiety is changed to an ester moiety to prepare the inventive compounds.
[0159] An exemplary synthetic scheme for preparing SAHP is shown in FIG. 13 . Those of skill in the art will realize that based on this teaching and those in the art as referenced above one could prepare any of the esterase-sensitive compounds of the invention.
[0160] In yet another aspect of the invention, methods for producing intermediates useful for the preparation of certain compounds of the invention are provided.
[0161] In one aspect of the invention, a method for the synthesis of the core structure of certain compounds is provided, one method comprising steps of:
[0162] providing an epoxy alcohol having the structure:
[0000]
[0163] reacting the epoxy alcohol with a reagent having the structure R 2 XH under suitable conditions to generate a diol having the core structure:
[0000]
[0164] reacting the diol with a reagent having the structure R 3 CH(OMe) 2 under suitable conditions to generate a scaffold having the core structure:
[0000]
[0165] wherein R 1 is hydrogen, or an aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic or heteroaromatic moiety;
[0166] R 2 is hydrogen, a protecting group, or an aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic or heteroaromatic moiety;
[0167] X is −O—, —C(R 2A ) 2 —, —S—, or —NR 2A —, wherein R 2A is hydrogen, a protecting group, or an aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic or heteroaromatic moiety;
[0168] or wherein two or more occurrences of R 2 and R 2A , taken together, form an alicyclic or heterocyclic moiety, or an aryl or heteroaryl moiety;
[0169] R 3 is an aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic or heteroaromatic moiety; and
[0170] R Z is an aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic or heteroaromatic moiety and is optionally attached to a solid support.
[0171] In certain exemplary embodiments, the epoxy alcohol has the structure:
[0000]
[0172] the diol has the structure:
[0000]
[0173] and the core scaffold has the structure:
[0000]
[0174] In certain other exemplary embodiments, the epoxy alcohol has the structure:
[0000]
[0175] the diol has the structure:
[0000]
[0176] and the the core scaffold has the structure:
[0000]
[0177] In certain embodiments, R 3 has the following structure:
[0000]
and the method described above generates the structure:
[0000]
[0179] In another aspect of the invention, a method for the synthesis of the core structure of certain compounds of the invention is provided, one method comprising steps of:
[0180] providing an epoxy alcohol having the structure:
[0000]
[0181] reacting the epoxy alcohol with a reagent having the structure R 2 XH under suitable conditions to generate a diol having the core structure:
[0000]
[0182] subjecting the diol to a reagent having the structure:
[0000]
[0000] wherein R 4C is a nitrogen protecting group; to suitable conditions to generate an amine having the structure:
[0000]
reacting the amine with a reagent having the structure:
[0000]
[0000] under suitable conditions to generate a scaffold having the core structure:
[0000]
[0184] wherein R 1 is hydrogen, or an aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic or heteroaromatic moiety;
[0185] R 2 is hydrogen, a protecting group, or an aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic or heteroaromatic moiety;
[0186] X is −O—, —C(R 2A ) 2 —, —S—, or —NR 2A —, wherein R 2A is hydrogen, a protecting group, or an aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic or heteroaromatic moiety;
[0187] or wherein two or more occurrences of R 2 and R 2A , taken together, form an alicyclic or heterocyclic moiety, or an aryl or heteroaryl moiety;
[0188] r is 0 or 1;
[0189] s is an integer from 2-5;
[0190] w is an integer from 0-4;
[0191] R 4A comprises a metal chelator;
[0192] each occurrence of R 4D is independently hydrogen, alkyl, heteroalkyl, cycloalkyl, heterocyclic, alkenyl, alkynyl, aryl, heteroaryl, halogen, CN, NO 2 , or WR W1 wherein W is O, S, NR W2 , —C(═O), —S(═O), —SO 2 , —C(═O)O—, —OC(═O), —C(═O)NR W2 , —NR W2 C(═O); wherein each occurrence of R W1 and R W2 is independently hydrogen, a protecting group, a prodrug moiety or an alkyl, cycloalkyl, heteroalkyl, heterocyclic, aryl or heteroaryl moiety, or, when W is NR W2 , R W1 and R W2 , taken together with the nitrogen atom to which they are attached, form a heterocyclic or heteroaryl moiety; or any two adjacent occurrences of R 2B , taken together with the atoms to which they are attached, form a substituted or unsubstituted, saturated or unsaturated alicyclic or heterocyclic moiety, or a substituted or unsubstituted aryl or heteroaryl moiety; and
[0193] R Z is an aliphatic, alicyclic, heteroaliphatic, heterocyclic, aromatic or heteroaromatic moiety and is optionally attached to a solid support.
[0194] In certain exemplary embodiments, the epoxy alcohol has the structure:
[0000]
[0195] the diol has the structure:
[0000]
[0196] the amine has the structure:
[0000]
[0197] and the core scaffold has the structure:
[0000]
[0198] In certain exemplary embodiments, the epoxy alcohol has the structure:
[0000]
[0199] the diol has the structure:
[0000]
[0200] the amine has the structure:
[0000]
[0201] and the core scaffold has the structure:
[0000]
[0202] In certain embodiments, the methods described above are carried out in solution phase. In certain other embodiments, the methods described above are carried out on a solid phase. In certain embodiments, the synthetic method is amenable to high-throughput techniques or to techniques commonly used in combinatorial chemistry.
Pharmaceutical Compositions
[0203] As discussed above, the present invention provides novel compounds having antitumor and antiproliferative activity, and thus the inventive compounds are useful for the treatment of cancer (e.g., cutaneous T-cell lymphoma). Benign proliferative diseases may also be treated using the inventive compounds. The compounds are also useful in the treatment of other diseases or condition that benefit from inhibition of deacetylation activity (e.g. HDAC inhibition). In certain embodiments, the compounds are useful in the treatment of baldness based on the discovery that HDAC inhibition (particularly, HDAC6 inhibition) blocks androgen signaling vis hsp90. HDAC inhibition has also been shown to inhibit estrogen signaling. In certain embodiments, the compounds are useful in blocking the hyperpigmentation of skin by HDAC inhibition.
[0204] Accordingly, in another aspect of the present invention, pharmaceutical compositions are provided, which comprise any one of the compounds described herein (or a prodrug, pharmaceutically acceptable salt or other pharmaceutically acceptable derivative thereof), and optionally comprise a pharmaceutically acceptable carrier. In certain embodiments, these compositions optionally further comprise one or more additional therapeutic agents. Alternatively, a compound of this invention may be administered to a patient in need thereof in combination with the administration of one or more other therapeutic agents. For example, additional therapeutic agents for conjoint administration or inclusion in a pharmaceutical composition with a compound of this invention may be an approved chemotherapeutic agent, or it may be any one of a number of agents undergoing approval in the Food and Drug Administration that ultimately obtain approval for the treatment of hair loss, skin hyperpigmentation, protozoal infections, and/or any disorder associated with cellular hyperproliferation. In certain other embodiments, the additional therapeutic agent is an anticancer agent, as discussed in more detail herein. In certain other embodiments, the compositions of the invention are useful for the treatment of protozoal infections.
[0205] It will also be appreciated that certain of the compounds of present invention can exist in free form for treatment, or where appropriate, as a pharmaceutically acceptable derivative thereof. According to the present invention, a pharmaceutically acceptable derivative includes, but is not limited to, pharmaceutically acceptable salts, esters, salts of such esters, or a pro-drug or other adduct or derivative of a compound of this invention which upon administration to a patient in need is capable of providing, directly or indirectly, a compound as otherwise described herein, or a metabolite or residue thereof.
[0206] As used herein, the term “pharmaceutically acceptable salt” refers to those salts which are, within the scope of sound medical judgment, suitable for use in contact with the tissues of humans and lower animals without undue toxicity, irritation, allergic response and the like, and are commensurate with a reasonable benefit/risk ratio. Pharmaceutically acceptable salts of amines, carboxylic acids, and other types of compounds, are well known in the art. For example, S. M. Berge, et al. describe pharmaceutically acceptable salts in detail in J. Pharmaceutical Sciences, 66: 1-19 (1977), incorporated herein by reference. The salts can be prepared in situ during the final isolation and purification of the compounds of the invention, or separately by reacting a free base or free acid function with a suitable reagent, as described generally below. For example, a free base function can be reacted with a suitable acid. Furthermore, where the compounds of the invention carry an acidic moiety, suitable pharmaceutically acceptable salts thereof may, include metal salts such as alkali metal salts, e.g. sodium or potassium salts; and alkaline earth metal salts, e.g. calcium or magnesium salts. Examples of pharmaceutically acceptable, nontoxic acid addition salts are salts of an amino group formed with inorganic acids such as hydrochloric acid, hydrobromic acid, phosphoric acid, sulfuric acid and perchloric acid or with organic acids such as acetic acid, oxalic acid, maleic acid, tartaric acid, citric acid, succinic acid or malonic acid or by using other methods used in the art such as ion exchange. Other pharmaceutically acceptable salts include adipate, alginate, ascorbate, aspartate, benzenesulfonate, benzoate, bisulfate, borate, butyrate, camphorate, camphorsulfonate, citrate, cyclopentanepropionate, digluconate, dodecylsulfate, ethanesulfonate, formate, fumarate, glucoheptonate, glycerophosphate, gluconate, hernisulfate, heptanoate, hexanoate, hydroiodide, 2-hydroxy-ethanesulfonate, lactobionate, lactate, laurate, lauryl sulfate, malate, maleate, malonate, methanesulfonate, 2-naphthalenesulfonate, nicotinate, nitrate, oleate, oxalate, palmitate, pamoate, pectinate, persulfate, 3-phenylpropionate, phosphate, picrate, pivalate, propionate, stearate, succinate, sulfate, tartrate, thiocyanate, p-toluenesulfonate, undecanoate, valerate salts, and the like. Representative alkali or alkaline earth metal salts include sodium, lithium, potassium, calcium, magnesium, and the like. Further pharmaceutically acceptable salts include, when appropriate, nontoxic ammonium, quaternary ammonium, and amine cations formed using counterions such as halide, hydroxide, carboxylate, sulfate, phosphate, nitrate, lower alkyl sulfonate and aryl sulfonate.
[0207] Additionally, as used herein, the term “pharmaceutically acceptable ester” refers to esters that hydrolyze in vivo and include those that break down readily in the human body to leave the parent compound or a salt thereof. Suitable ester groups include, for example, those derived from pharmaceutically acceptable aliphatic carboxylic acids, particularly alkanoic, alkenoic, cycloalkanoic and alkanedioic acids, in which each alkyl or alkenyl moeity advantageously has not more than 6 carbon atoms. Examples of particular esters include formates, acetates, propionates, butyrates, acrylates and ethylsuccinates.
[0208] Furthermore, the term “pharmaceutically acceptable prodrugs” as used herein refers to those prodrugs of the compounds of the present invention which are, within the scope of sound medical judgment, suitable for use in contact with the issues of humans and lower animals with undue toxicity, irritation, allergic response, and the like, commensurate with a reasonable benefit/risk ratio, and effective for their intended use, as well as the zwitterionic forms, where possible, of the compounds of the invention. The term “prodrug” refers to compounds that are rapidly transformed in vivo to yield the parent compound of the above formula, for example by hydrolysis in blood. A thorough discussion is provided in T. Higuchi and V. Stella, Pro-drugs as Novel Delivery Systems, Vol. 14 of the A.C.S. Symposium Series, and in Edward B. Roche, ed., Bioreversible Carriers in Drug Design, American Pharmaceutical Association and Pergamon Press, 1987, both of which are incorporated herein by reference.
[0209] As described above, the pharmaceutical compositions of the present invention additionally comprise a pharmaceutically acceptable carrier, which, as used herein, includes any and all solvents, diluents, or other liquid vehicle, dispersion or suspension aids, surface active agents, isotonic agents, thickening or emulsifying agents, preservatives, solid binders, lubricants and the like, as suited to the particular dosage form desired. Remington's Pharmaceutical Sciences, Sixteenth Edition, E. W. Martin (Mack Publishing Co., Easton, Pa., 1980) discloses various carriers used in formulating pharmaceutical compositions and known techniques for the preparation thereof. Except insofar as any conventional carrier medium is incompatible with the compounds of the invention, such as by producing any undesirable biological effect or otherwise interacting in a deleterious manner with any other component(s) of the pharmaceutical composition, its use is contemplated to be within the scope of this invention. Some examples of materials which can serve as pharmaceutically acceptable carriers include, but are not limited to, sugars such as lactose, glucose and sucrose; starches such as corn starch and potato starch; cellulose and its derivatives such as sodium carboxymethyl cellulose, ethyl cellulose and cellulose acetate; powdered tragacanth; malt; gelatine; talc; excipients such as cocoa butter and suppository waxes; oils such as peanut oil, cottonseed oil; safflower oil, sesame oil; olive oil; corn oil and soybean oil; glycols; such as propylene glycol; esters such as ethyl oleate and ethyl laurate; agar; buffering agents such as magnesium hydroxide and aluminum hydroxide; alginic acid; pyrogen free water; isotonic saline; Ringer's solution; ethyl alcohol, and phosphate buffer solutions, as well as other non-toxic compatible lubricants such as sodium lauryl sulfate and magnesium stearate, as well as coloring agents, releasing agents, coating agents, sweetening, flavoring and perfuming agents, preservatives and antioxidants can also be present in the composition, according to the judgment of the formulator.
[0210] Liquid dosage forms for oral administration include, but are not limited to, pharmaceutically acceptable emulsions, microemulsions, solutions, suspensions, syrups and elixirs. In addition to the active compounds, the liquid dosage forms may contain inert diluents commonly used in the art such as, for example, water or other solvents, solubilizing agents and emulsifiers such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butylene glycol, dimethylformamide, oils (in particular, cottonseed, groundnut, corn, germ, olive, castor, and sesame oils), glycerol, tetrahydrofurfuryl alcohol, polyethylene glycols and fatty acid esters of sorbitan, and mixtures thereof. Besides inert diluents, the oral compositions can also include adjuvants such as wetting agents, emulsifying and suspending agents, sweetening, flavoring, and perfuming agents.
[0211] Injectable preparations, for example, sterile injectable aqueous or oleaginous suspensions may be formulated according to the known art using suitable dispersing or wetting agents and suspending agents. The sterile injectable preparation may also be a sterile injectable solution, suspension or emulsion in a nontoxic parenterally acceptable diluent or solvent, for example, as a solution in 1,3-butanediol. Among the acceptable vehicles and solvents that may be employed are water, Ringer's solution, U.S.P. and isotonic sodium chloride solution. In addition, sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose any bland fixed oil can be employed including synthetic mono- or diglycerides. In addition, fatty acids such as oleic acid are used in the preparation of injectables.
[0212] The injectable formulations can be sterilized, for example, by filtration through a bacterial-retaining filter, or by incorporating sterilizing agents in the form of sterile solid compositions which can be dissolved or dispersed in sterile water or other sterile injectable medium prior to use.
[0213] In order to prolong the effect of a drug, it is often desirable to slow the absorption of the drug from subcutaneous or intramuscular injection. This may be accomplished by the use of a liquid suspension or crystalline or amorphous material with poor water solubility. The rate of absorption of the drug then depends upon its rate of dissolution that, in turn, may depend upon crystal size and crystalline form. Alternatively, delayed absorption of a parenterally administered drug form is accomplished by dissolving or suspending the drug in an oil vehicle. Injectable depot forms are made by forming microencapsule matrices of the drug in biodegradable polymers such as polylactide-polyglycolide. Depending upon the ratio of drug to polymer and the nature of the particular polymer employed, the rate of drug release can be controlled. Examples of other biodegradable polymers include (poly(orthoesters) and poly(anhydrides). Depot injectable formulations are also prepared by entrapping the drug in liposomes or microemulsions which are compatible with body tissues.
[0214] Compositions for rectal or vaginal administration are preferably suppositories which can be prepared by mixing the compounds of this invention with suitable non-irritating excipients or carriers such as cocoa butter, polyethylene glycol or a suppository wax which are solid at ambient temperature but liquid at body temperature and therefore melt in the rectum or vaginal cavity and release the active compound.
[0215] Solid dosage forms for oral administration include capsules, tablets, pills, powders, and granules. In such solid dosage forms, the active compound is mixed with at least one inert, pharmaceutically acceptable excipient or carrier such as sodium citrate or dicalcium phosphate and/or a) fillers or extenders such as starches, lactose, sucrose, glucose, mannitol, and silicic acid, b) binders such as, for example, carboxymethylcellulose, alginates, gelatin, polyvinylpyrrolidinone, sucrose, and acacia, c) humectants such as glycerol, d) disintegrating agents such as agar-agar, calcium carbonate, potato or tapioca starch, alginic acid, certain silicates, and sodium carbonate, e) solution retarding agents such as paraffin, absorption accelerators such as quaternary ammonium compounds, g) wetting agents such as, for example, cetyl alcohol and glycerol monostearate, h) absorbents such as kaolin and bentonite clay, and i) lubricants such as talc, calcium stearate, magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate, and mixtures thereof. In the case of capsules, tablets and pills, the dosage form may also comprise buffering agents.
[0216] Solid compositions of a similar type may also be employed as fillers in soft and hard-filled gelatin capsules using such excipients as lactose or milk sugar as well as high molecular weight polyethylene glycols and the like. The solid dosage forms of tablets, dragees, capsules, pills, and granules can be prepared with coatings and shells such as enteric coatings and other coatings well known in the pharmaceutical formulating art. They may optionally contain opacifying agents and can also be of a composition that they release the active ingredient(s) only, or preferentially, in a certain part of the intestinal tract, optionally, in a delayed manner Examples of embedding compositions that can be used include polymeric substances and waxes. Solid compositions of a similar type may also be employed as fillers in soft and hard-filled gelatin capsules using such excipients as lactose or milk sugar as well as high molecular weight polyethylene glycols and the like.
[0217] The active compounds can also be in micro-encapsulated form with one or more excipients as noted above. The solid dosage forms of tablets, dragees, capsules, pills, and granules can be prepared with coatings and shells such as enteric coatings, release controlling coatings and other coatings well known in the pharmaceutical formulating art. In such solid dosage forms the active compound may be admixed with at least one inert diluent such as sucrose, lactose and starch. Such dosage forms may also comprise, as in normal practice, additional substances other than inert diluents, e.g., tableting lubricants and other tableting aids such as magnesium stearate and microcrystalline cellulose. In the case of capsules, tablets and pills, the dosage forms may also comprise buffering agents. They may optionally contain opacifying agents and can also be of a composition that they release the active ingredient(s) only, or preferentially, in a certain part of the intestinal tract, optionally, in a delayed manner Examples of embedding compositions which can be used include polymeric substances and waxes.
[0218] The present invention encompasses pharmaceutically acceptable topical formulations of inventive compounds. The term “pharmaceutically acceptable topical formulation”, as used herein, means any formulation which is pharmaceutically acceptable for intradermal administration of a compound of the invention by application of the formulation to the epidermis. In certain embodiments of the invention, the topical formulation comprises a carrier system. Pharmaceutically effective carriers include, but are not limited to, solvents (e.g., alcohols, poly alcohols, water), creams, lotions, ointments, oils, plasters, liposomes, powders, emulsions, microemulsions, and buffered solutions (e.g., hypotonic or buffered saline) or any other carrier known in the art for topically administering pharmaceuticals. A more complete listing of art-known carriers is provided by reference texts that are standard in the art, for example, Remington's Pharmaceutical Sciences, 16th Edition, 1980 and 17th Edition, 1985, both published by Mack Publishing Company, Easton, Pa., the disclosures of which are incorporated herein by reference in their entireties. In certain other embodiments, the topical formulations of the invention may comprise excipients. Any pharmaceutically acceptable excipient known in the art may be used to prepare the inventive pharmaceutically acceptable topical formulations. Examples of excipients that can be included in the topical formulations of the invention include, but are not limited to, preservatives, antioxidants, moisturizers, emollients, buffering agents, solubilizing agents, other penetration agents, skin protectants, surfactants, and propellants, and/or additional therapeutic agents used in combination to the inventive compound. Suitable preservatives include, but are not limited to, alcohols, quaternary amines, organic acids, parabens, and phenols. Suitable antioxidants include, but are not limited to, ascorbic acid and its esters, sodium bisulfite, butylated hydroxytoluene, butylated hydroxyanisole, tocopherols, and chelating agents like EDTA and citric acid. Suitable moisturizers include, but are not limited to, glycerine, sorbitol, polyethylene glycols, urea, and propylene glycol. Suitable buffering agents for use with the invention include, but are not limited to, citric, hydrochloric, and lactic acid buffers. Suitable solubilizing agents include, but are not limited to, quaternary ammonium chlorides, cyclodextrins, benzyl benzoate, lecithin, and polysorbates. Suitable skin protectants that can be used in the topical formulations of the invention include, but are not limited to, vitamin E oil, allatoin, dimethicone, glycerin, petrolatum, and zinc oxide.
[0219] In certain embodiments, the pharmaceutically acceptable topical formulations of the invention comprise at least a compound of the invention and a penetration enhancing agent. The choice of topical formulation will depend or several factors, including the condition to be treated, the physicochemical characteristics of the inventive compound and other excipients present, their stability in the formulation, available manufacturing equipment, and costs constraints. As used herein the term “penetration enhancing agent” means an agent capable of transporting a pharmacologically active compound through the stratum corneum and into the epidermis or dermis, preferably, with little or no systemic absorption. A wide variety of compounds have been evaluated as to their effectiveness in enhancing the rate of penetration of drugs through the skin. See, for example, Percutaneous Penetration Enhancers , Maibach H. I. and Smith H. E. (eds.), CRC Press, Inc., Boca Raton, Fla. (1995), which surveys the use and testing of various skin penetration enhancers, and Buyuktimkin et al., Chemical Means of Transdermal Drug Permeation Enhancement in Transdermal and Topical Drug Delivery Systems, Gosh T. K., Pfister W. R., Yum S. I. (Eds.), Interpharm Press Inc., Buffalo Grove, Ill. (1997). In certain exemplary embodiments, penetration agents for use with the invention include, but are not limited to, triglycerides (e.g., soybean oil), aloe compositions (e.g., aloe-vera gel), ethyl alcohol, isopropyl alcohol, octolyphenylpolyethylene glycol, oleic acid, polyethylene glycol 400, propylene glycol, N-decylmethylsulfoxide, fatty acid esters (e.g., isopropyl myristate, methyl laurate, glycerol monooleate, and propylene glycol monooleate), and N-methyl pyrrolidone.
[0220] In certain embodiments, the compositions may be in the form of ointments, pastes, creams, lotions, gels, powders, solutions, sprays, inhalants or patches. In certain exemplary embodiments, formulations of the compositions according to the invention are creams, which may further contain saturated or unsaturated fatty acids such as stearic acid, palmitic acid, oleic acid, palmito-oleic acid, cetyl or oleyl alcohols, stearic acid being particularly preferred. Creams of the invention may also contain a non-ionic surfactant, for example, polyoxy-40-stearate. In certain embodiments, the active component is admixed under sterile conditions with a pharmaceutically acceptable carrier and any needed preservatives or buffers as may be required. Ophthalmic formulation, eardrops, and eye drops are also contemplated as being within the scope of this invention. Additionally, the present invention contemplates the use of transdermal patches, which have the added advantage of providing controlled delivery of a compound to the body. Such dosage forms are made by dissolving or dispensing the compound in the proper medium. As discussed above, penetration enhancing agents can also be used to increase the flux of the compound across the skin. The rate can be controlled by either providing a rate controlling membrane or by dispersing the compound in a polymer matrix or gel.
[0221] It will also be appreciated that the compounds and pharmaceutical compositions of the present invention can be formulated and employed in combination therapies, that is, the compounds and pharmaceutical compositions can be formulated with or administered concurrently with, prior to, or subsequent to, one or more other desired therapeutics or medical procedures. The particular combination of therapies (therapeutics or procedures) to employ in a combination regimen will take into account compatibility of the desired therapeutics and/or procedures and the desired therapeutic effect to be achieved. It will also be appreciated that the therapies employed may achieve a desired effect for the same disorder (for example, an inventive compound may be administered concurrently with another immunomodulatory agent, anticancer agent or agent useful for the treatment of psoriasis), or they may achieve different effects (e.g., control of any adverse effects).
[0222] For example, other therapies or anticancer agents that may be used in combination with the inventive compounds of the present invention include surgery, radiotherapy (in but a few examples, γ-radiation, neutron beam radiotherapy, electron beam radiotherapy, proton therapy, brachytherapy, and systemic radioactive isotopes, to name a few), endocrine therapy, biologic response modifiers (interferons, interleukins, and tumor necrosis factor (TNF) to name a few), hyperthermia and cryotherapy, agents to attenuate any adverse effects (e.g., antiemetics), and other approved chemotherapeutic drugs, including, but not limited to, alkylating drugs (mechlorethamine, chlorambucil, Cyclophosphamide, Melphalan, Ifosfamide), antimetabolites (Methotrexate), purine antagonists and pyrimidine antagonists (6-Mercaptopurine, 5-Fluorouracil, Cytarabile, Gemcitabine), spindle poisons (Vinblastine, Vincristine, Vinorelbine, Paclitaxel), podophyllotoxins (Etoposide, Irinotecan, Topotecan), antibiotics (Doxorubicin, Bleomycin, Mitomycin), nitrosoureas (Carmustine, Lomustine), inorganic ions (Cisplatin, Carboplatin), enzymes (Asparaginase), and hormones (Tamoxifen, Leuprolide, Flutamide, and Megestrol), to name a few. For a more comprehensive discussion of updated cancer therapies see, The Merck Manual , Seventeenth Ed. 1999, the entire contents of which are hereby incorporated by reference. See also the National Cancer Institute (CNI) website (www.nci nih gov) and the Food and Drug Administration (FDA) website for a list of the FDA approved oncology drugs (www.fda.gov/cder/cancer/druglistframe).
[0223] In certain embodiments, the pharmaceutical compositions of the present invention further comprise one or more additional therapeutically active ingredients (e.g., chemotherapeutic and/or palliative). For purposes of the invention, the term “palliative” refers to treatment that is focused on the relief of symptoms of a disease and/or side effects of a therapeutic regimen, but is not curative. For example, palliative treatment encompasses painkillers, antinausea medications and anti-sickness drugs. In addition, chemotherapy, radiotherapy and surgery can all be used palliatively (that is, to reduce symptoms without going for cure; e.g., for shrinking tumors and reducing pressure, bleeding, pain and other symptoms of cancer).
[0224] Additionally, the present invention provides pharmaceutically acceptable derivatives of the inventive compounds, and methods of treating a subject using these compounds, pharmaceutical compositions thereof, or either of these in combination with one or more additional therapeutic agents.
[0225] It will also be appreciated that certain of the compounds of present invention can exist in free form for treatment, or where appropriate, as a pharmaceutically acceptable derivative thereof. According to the present invention, a pharmaceutically acceptable derivative includes, but is not limited to, pharmaceutically acceptable salts, esters, salts of such esters, or a prodrug or other adduct or derivative of a compound of this invention which upon administration to a patient in need is capable of providing, directly or indirectly, a compound as otherwise described herein, or a metabolite or residue thereof.
Research Uses, Pharmaceutical Uses and Methods of Treatment
Research Uses
[0226] According to the present invention, the inventive compounds may be assayed in any of the available assays known in the art for identifying compounds having antiprotozoal, HDAC inhibitory, hair growth, androgen signalling inhibitory, estrogen signaling inhibitory, and/or antiproliferative activity. For example, the assay may be cellular or non-cellular, in vivo or in vitro, high- or low-throughput format, etc.
[0227] Thus, in one aspect, compounds of this invention which are of particular interest include those which:
exhibit HDAC-inhibitory activity; exhibit HDAC Class I inhibitory activity (e.g., HDAC1, HDAC2, HDAC3, HDAC8); exhibit HDAC Class II inhibitory activity (e.g., HDAC4, HDAC5, HDAC6, HDAC7, HDAC9a, HDAC9b, HDRP/HDAC9c, HDAC10); exhibit the ability to inhibit HDAC1 (Genbank Accession No. NP_004955, incorporated herein by reference); exhibit the ability to inhibit HDAC2 (Genbank Accession No. NP_001518, incorporated herein by reference); exhibit the ability to inhibit HDAC3 (Genbank Accession No. O15739, incorporated herein by reference); exhibit the ability to inhibit HDAC4 (Genbank Accession No. AAD29046, incorporated herein by reference); exhibit the ability to inhibit HDAC5 (Genbank Accession No. NP_005465, incorporated herein by reference); exhibit the ability to inhibit HDAC6 (Genbank Accession No. NP_006035, incorporated herein by reference); exhibit the ability to inhibit HDAC7 (Genbank Accession No. AAP63491, incorporated herein by reference); exhibit the ability to inhibit HDAC8 (Genbank Accession No. AAF73428, NM_018486, AF245664, AF230097, each of which is incorporated herein by reference); exhibit the ability to inhibit HDAC9 (Genbank Accession No. NM_178425, NM_178423, NM_058176, NM_014707, BC111735, NM_058177, each of which is incorporated herein by reference) exhibit the ability to inhibit HDAC10 (Genbank Accession No. NM_032019, incorporated herein by reference) exhibit the ability to inhibit HDAC11 (Genbank Accession No. BC009676, incorporated herein by reference); exhibit the ability to inhibit tubulin deactetylation (TDAC); exhibit the ability to modulate the glucose-sensitive subset of genes downstream of Ure2p; exhibit cytotoxic or growth inhibitory effect on cancer cell lines maintained in vitro or in animal studies using a scientifically acceptable cancer cell xenograft model; and/or exhibit a therapeutic profile (e.g., optimum safety and curative effect) that is superior to existing chemotherapeutic agents.
[0246] As detailed in the exemplification herein, in assays to determine the ability of compounds to inhibit cancer cell growth certain inventive compounds may exhibit IC 50 values ≦100 μM. In certain other embodiments, inventive compounds exhibit IC 50 values ≦50 μM. In certain other embodiments, inventive compounds exhibit IC 50 values ≦40 μM. In certain other embodiments, inventive compounds exhibit IC 50 values ≦30 μM. In certain other embodiments, inventive compounds exhibit IC 50 values ≦20 μM. In certain other embodiments, inventive compounds exhibit IC 50 values ≦10 μM. In certain other embodiments, inventive compounds exhibit IC 50 values ≦7.5 μM. In certain embodiments, inventive compounds exhibit IC 50 values ≦5 μM. In certain other embodiments, inventive compounds exhibit IC 50 values ≦2.5 μM. In certain embodiments, inventive compounds exhibit IC 50 values ≦1 μM. In certain embodiments, inventive compounds exhibit IC 50 values ≦0.75 μM. In certain embodiments, inventive compounds exhibit IC 50 values ≦0.5 μM. In certain embodiments, inventive compounds exhibit IC 50 values ≦0.25 μM. In certain embodiments, inventive compounds exhibit IC 50 values ≦0.1 μM. In certain other embodiments, inventive compounds exhibit IC 50 values ≦75 nM. In certain other embodiments, inventive compounds exhibit IC 50 values ≦50 nM. In certain other embodiments, inventive compounds exhibit IC 50 values ≦25 nM. In certain other embodiments, inventive compounds exhibit IC 50 values ≦10 nM. In other embodiments, exemplary compounds exhibited IC 50 values ≦7.5 nM. In other embodiments, exemplary compounds exhibited IC 50 values ≦5 nM.
Pharmaceutical Uses and Methods of Treatment
[0247] In general, methods of using the compounds of the present invention comprise administering to a subject in need thereof a therapeutically effective amount of a compound of the present invention. The compounds of the invention are generally inhibitors of deacetyalse activity. As discussed above, the compounds of the invention are typically inhibitors of histone deacetylases and, as such, are useful in the treatment of disorders modulated by histone deacetylases. Other deacetylase such as tubulin deacetylases may also be inhibited by the inventive compounds.
[0248] In certain embodiments, compounds of the invention are useful in the treatment of proliferative diseases (e.g., cancer, benign neoplasms, inflammatory disease, autoimmune diseases). In certain embodiments, given the esterase sensitive ester linkage in the compounds of the invention, they are particularly useful in treating skin disorders modulated by histone deacetyalses where systemic effects of the drug are to be avoided or at least minimized. This feature of the inventive compounds may allow the use of compounds normally too toxic for administration to a subject systemically. In certain embodiments, these skin disorders are proliferative disorders. For example, the inventive compounds are particularly useful in the treatment of skin cancer and benign skin tumors. In certain embodiments, the compounds are useful in the treatment of cutaneous T-cell lymphoma. In certain embodiments, the compounds are useful in the treatment of neurofibromatosis. Accordingly, in yet another aspect, according to the methods of treatment of the present invention, tumor cells are killed, or their growth is inhibited by contacting said tumor cells with an inventive compound or composition, as described herein. In other embodiments, the compounds are useful in treating inflammatory diseases of the skin such as psoriasis or dermatitis. In other embodiments, the compounds are useful in the treatment or prevention of hair loss. In certain embodiments, the compounds are useful in the treatment of diseases associated with skin pigmentation. For example, the compounds may be used to prevent the hyperpigmentation of skin.
[0249] Thus, in another aspect of the invention, methods for the treatment of cancer are provided comprising administering a therapeutically effective amount of an inventive compound, as described herein, to a subject in need thereof. In certain embodiments, a method for the treatment of cancer is provided comprising administering a therapeutically effective amount of an inventive compound, or a pharmaceutical composition comprising an inventive compound to a subject in need thereof, in such amounts and for such time as is necessary to achieve the desired result. Preferably, the inventive compounds is administered topically. In certain embodiments of the present invention a “therapeutically effective amount” of the inventive compound or pharmaceutical composition is that amount effective for killing or inhibiting the growth of tumor cells. The compounds and compositions, according to the method of the present invention, may be administered using any amount and any route of administration effective for killing or inhibiting the growth of tumor cells. Thus, the expression “amount effective to kill or inhibit the growth of tumor cells,” as used herein, refers to a sufficient amount of agent to kill or inhibit the growth of tumor cells. The exact amount required will vary from subject to subject, depending on the species, age, and general condition of the subject, the severity of the infection, the particular anticancer agent, its mode of administration, and the like. In certain embodiments of the present invention a “therapeutically effective amount” of the inventive compound or pharmaceutical composition is that amount effective for inhibiting deacetylase activity (in particular, HDAC activity) in skin cells. In certain embodiments of the present invention a “therapeutically effective amount” of the inventive compound or pharmaceutical composition is that amount effective to kill or inhibit the growth of skin cells.
[0250] In certain embodiments, the method involves the administration of a therapeutically effective amount of the compound or a pharmaceutically acceptable derivative thereof to a subject (including, but not limited to a human or animal) in need of it. In certain embodiments, the inventive compounds as useful for the treatment of cancer (including, but not limited to, glioblastoma, retinoblastoma, breast cancer, cervical cancer, colon and rectal cancer, leukemia, lymphoma, lung cancer (including, but not limited to small cell lung cancer), melanoma and/or skin cancer, multiple myeloma, non-Hodgkin's lymphoma, ovarian cancer, pancreatic cancer, prostate cancer and gastric cancer, bladder cancer, uterine cancer, kidney cancer, testicular cancer, stomach cancer, brain cancer, liver cancer, or esophageal cancer).
[0251] In certain embodiments, the inventive anticancer agents are useful in the treatment of cancers and other proliferative disorders, including, but not limited to breast cancer, cervical cancer, colon and rectal cancer, leukemia, lung cancer, melanoma, multiple myeloma, non-Hodgkin's lymphoma, ovarian cancer, pancreatic cancer, prostate cancer, and gastric cancer, to name a few. In certain embodiments, the inventive anticancer agents are active against leukemia cells and melanoma cells, and thus are useful for the treatment of leukemias (e.g., myeloid, lymphocytic, myelocytic and lymphoblastic leukemias) and malignant melanomas. In still other embodiments, the inventive anticancer agents are active against solid tumors.
[0252] In certain embodiments, the inventive compounds also find use in the prevention of restenosis of blood vessels subject to traumas such as angioplasty and stenting. For example, it is contemplated that the compounds of the invention will be useful as a coating for implanted medical devices, such as tubings, shunts, catheters, artificial implants, pins, electrical implants such as pacemakers, and especially for arterial or venous stents, including balloon-expandable stents. In certain embodiments inventive compounds may be bound to an implantable medical device, or alternatively, may be passively adsorbed to the surface of the implantable device. In certain other embodiments, the inventive compounds may be formulated to be contained within, or, adapted to release by a surgical or medical device or implant, such as, for example, stents, sutures, indwelling catheters, prosthesis, and the like. For example, drugs having antiproliferative and anti-inflammatory activities have been evaluated as stent coatings, and have shown promise in preventing restenosis (See, for example, Presbitero P. et al., “Drug eluting stents do they make the difference?”, Minerva Cardioangiol, 2002, 50(5):431-442; Ruygrok P. N. et al., “Rapamycin in cardiovascular medicine”, Intern. Med. J., 2003, 33(3):103-109; and Marx S. O. et al., “Bench to bedside: the development of rapamycin and its application to stent restenosis”, Circulation, 2001, 104(8):852-855, each of these references is incorporated herein by reference in its entirety). Accordingly, without wishing to be bound to any particular theory, Applicant proposes that inventive compounds having antiproliferative effects can be used as stent coatings and/or in stent drug delivery devices, inter alia for the prevention of restenosis or reduction of restenosis rate. Suitable coatings and the general preparation of coated implantable devices are described in U.S. Pat. Nos. 6,099,562; 5,886,026; and 5,304,121. The coatings are typically biocompatible polymeric materials such as a hydrogel polymer, polymethyldisiloxane, polycaprolactone, polyethylene glycol, polylactic acid, ethylene vinyl acetate, and mixtures thereof. The coatings may optionally be further covered by a suitable topcoat of fluorosilicone, polysaccarides, polyethylene glycol, phospholipids or combinations thereof to impart controlled release characteristics in the composition. A variety of compositions and methods related to stent coating and/or local stent drug delivery for preventing restenosis are known in the art (see, for example, U.S. Pat. Nos. 6,517,889; 6,273,913; 6,258,121; 6,251,136; 6,248,127; 6,231,600; 6,203,551; 6,153,252; 6,071,305; 5,891,507; 5,837,313 and published U.S. patent application No.: US2001/0027340, each of which is incorporated herein by reference in its entirety). For example, stents may be coated with polymer-drug conjugates by dipping the stent in polymer-drug solution or spraying the stent with such a solution. In certain embodiment, suitable materials for the implantable device include biocompatible and nontoxic materials, and may be chosen from the metals such as nickel-titanium alloys, steel, or biocompatible polymers, hydrogels, polyurethanes, polyethylenes, ethylenevinyl acetate copolymers, etc. In certain embodiments, the inventive compound is coated onto a stent for insertion into an artery or vein following balloon angioplasty.
[0253] The compounds of this invention or pharmaceutically acceptable compositions thereof may also be incorporated into compositions for coating implantable medical devices, such as prostheses, artificial valves, vascular grafts, stents and catheters. Accordingly, the present invention, in another aspect, includes a composition for coating an implantable device comprising a compound of the present invention as described generally above, and in classes and subclasses herein, and a carrier suitable for coating said implantable device. In still another aspect, the present invention includes an implantable device coated with a composition comprising a compound of the present invention as described generally above, and in classes and subclasses herein, and a carrier suitable for coating said implantable device.
[0254] Within other aspects of the present invention, methods are provided for expanding the lumen of a body passageway, comprising inserting a stent into the passageway, the stent having a generally tubular structure, the surface of the structure being coated with (or otherwise adapted to release) an inventive compound or composition, such that the passageway is expanded. In certain embodiments, the lumen of a body passageway is expanded in order to eliminate a biliary, gastrointestinal, esophageal, tracheal/bronchial, urethral and/or vascular obstruction.
[0255] Methods for eliminating biliary, gastrointestinal, esophageal, tracheal/bronchial, urethral and/or vascular obstructions using stents are known in the art. The skilled practitioner will know how to adapt these methods in practicing the present invention. For example, guidance can be found in U.S. Patent Application Publication No.: 2003/0004209 in paragraphs [0146]-[0155], which paragraphs are hereby incorporated herein by reference.
[0256] Another aspect of the invention relates to a method for inhibiting the growth of multidrug resistant cells in a biological sample or a patient, which method comprises administering to the patient, or contacting said biological sample with a compound of formula I or a composition comprising said compound.
[0257] Additionally, the present invention provides pharmaceutically acceptable derivatives of the inventive compounds, and methods of treating a subject using these compounds, pharmaceutical compositions thereof, or either of these in combination with one or more additional therapeutic agents.
[0258] Another aspect of the invention relates to a method of treating or lessening the severity of a disease or condition associated with a proliferation disorder in a patient, said method comprising a step of administering to said patient, a compound of formula I or a composition comprising said compound.
[0259] It will be appreciated that the compounds and compositions, according to the method of the present invention, may be administered using any amount and any route of administration effective for the treatment of cancer and/or disorders associated with cell hyperproliferation. For example, when using the inventive compounds for the treatment of cancer, the expression “effective amount” as used herein, refers to a sufficient amount of agent to inhibit cell proliferation, or refers to a sufficient amount to reduce the effects of cancer. The exact amount required will vary from subject to subject, depending on the species, age, and general condition of the subject, the severity of the diseases, the particular anticancer agent, its mode of administration, and the like.
[0260] The compounds of the invention are preferably formulated in dosage unit form for ease of administration and uniformity of dosage. The expression “dosage unit form” as used herein refers to a physically discrete unit of therapeutic agent appropriate for the patient to be treated. It will be understood, however, that the total daily usage of the compounds and compositions of the present invention will be decided by the attending physician within the scope of sound medical judgment. The specific therapeutically effective dose level for any particular patient or organism will depend upon a variety of factors including the disorder being treated and the severity of the disorder; the activity of the specific compound employed; the specific composition employed; the age, body weight, general health, sex and diet of the patient; the time of administration, route of administration, and rate of excretion of the specific compound employed; the duration of the treatment; drugs used in combination or coincidental with the specific compound employed; and like factors well known in the medical arts (see, for example, Goodman and Gilman's, “The Pharmacological Basis of Therapeutics”, Tenth Edition, A. Gilman, J. Hardman and L. Limbird, eds., McGraw-Hill Press, 155-173, 2001, which is incorporated herein by reference in its entirety).
[0261] Another aspect of the invention relates to a method for inhibiting histone deacetylase activity in a biological sample or a patient, which method comprises administering to the patient, or contacting said biological sample with an inventive compound or a composition comprising said compound.
[0262] Furthermore, after formulation with an appropriate pharmaceutically acceptable carrier in a desired dosage, the pharmaceutical compositions of this invention can be administered to humans and other animals orally, rectally, parenterally, intracisternally, intravaginally, intraperitoneally, topically (as by powders, ointments, creams or drops), bucally, as an oral or nasal spray, or the like, depending on the severity of the infection being treated. In certain embodiments, the compounds of the invention may be administered at dosage levels of about 0.001 mg/kg to about 50 mg/kg, from about 0.01 mg/kg to about 25 mg/kg, or from about 0.1 mg/kg to about 10 mg/kg of subject body weight per day, one or more times a day, to obtain the desired therapeutic effect. It will also be appreciated that dosages smaller than 0.001 mg/kg or greater than 50 mg/kg (for example 50-100 mg/kg) can be administered to a subject. In certain embodiments, compounds are administered orally or parenterally.
Treatment Kit
[0263] In other embodiments, the present invention relates to a kit for conveniently and effectively carrying out the methods in accordance with the present invention. In general, the pharmaceutical pack or kit comprises one or more containers filled with one or more of the ingredients of the pharmaceutical compositions of the invention. Such kits are especially suited for the topical delivery of the inventive compounds. Optionally associated with such container(s) can be a notice in the form prescribed by a governmental agency regulating the manufacture, use or sale of pharmaceutical products, which notice reflects approval by the agency of manufacture, use or sale for human administration.
EQUIVALENTS
[0264] The representative examples which follow are intended to help illustrate the invention, and are not intended to, nor should they be construed to, limit the scope of the invention. Indeed, various modifications of the invention and many further embodiments thereof, in addition to those shown and described herein, will become apparent to those skilled in the art from the full contents of this document, including the examples which follow and the references to the scientific and patent literature cited herein. It should further be appreciated that, unless otherwise indicated, the entire contents of each of the references cited herein are incorporated herein by reference to help illustrate the state of the art. The following examples contain important additional information, exemplification and guidance which can be adapted to the practice of this invention in its various embodiments and the equivalents thereof.
[0265] These and other aspects of the present invention will be further appreciated upon consideration of the following Examples, which are intended to illustrate certain particular embodiments of the invention but are not intended to limit its scope, as defined by the claims.
Examples
[0266] The compounds of this invention and their preparation can be understood further by the examples that illustrate some of the processes by which these compounds are prepared or used. It will be appreciated, however, that these examples do not limit the invention. Variations of the invention, now known or further developed, are considered to fall within the scope of the present invention as described herein and as hereinafter claimed.
General Description of Synthetic Methods
[0267] The various references cited herein provide helpful background information on preparing compounds similar to the inventive compounds described herein or relevant intermediates, as well as information on formulation, uses, and administration of such compounds which may be of interest.
[0268] Moreover, the practitioner is directed to the specific guidance and examples provided in this document relating to various exemplary compounds and intermediates thereof.
[0269] The compounds of this invention and their preparation can be understood further by the examples that illustrate some of the processes by which these compounds are prepared or used. It will be appreciated, however, that these examples do not limit the invention. Variations of the invention, now known or further developed, are considered to fall within the scope of the present invention as described herein and as hereinafter claimed.
[0270] According to the present invention, any available techniques can be used to make or prepare the inventive compounds or compositions including them. For example, a variety of a variety combinatorial techniques, parallel synthesis and/or solid phase synthetic methods such as those discussed in detail below may be used. Alternatively or additionally, the inventive compounds may be prepared using any of a variety of solution phase synthetic methods known in the art.
[0271] It will be appreciated as described below, that a variety of inventive compounds can be synthesized according to the methods described herein. The starting materials and reagents used in preparing these compounds are either available from commercial suppliers such as Aldrich Chemical Company (Milwaukee, Wis.), Bachem (Torrance, Calif.), Sigma (St. Louis, Mo.), or are prepared by methods well known to a person of ordinary skill in the art following procedures described in such references as Fieser and Fieser 1991, “Reagents for Organic Synthesis”, vols 1-17, John Wiley and Sons, New York, N.Y., 1991; Rodd 1989 “Chemistry of Carbon Compounds”, vols. 1-5 and supps, Elsevier Science Publishers, 1989; “Organic Reactions”, vols 1-40, John Wiley and Sons, New York, N.Y., 1991; March 2001, “Advanced Organic Chemistry”, 5th ed. John Wiley and Sons, New York, N.Y.; and Larock 1990, “Comprehensive Organic Transformations: A Guide to Functional Group Preparations”, 2 nd ed. VCH Publishers. These schemes are merely illustrative of some methods by which the compounds of this invention can be synthesized, and various modifications to these schemes can be made and will be suggested to a person of ordinary skill in the art having regard to this disclosure.
[0272] The starting materials, intermediates, and compounds of this invention may be isolated and purified using conventional techniques, including filtration, distillation, crystallization, chromatography, and the like. They may be characterized using conventional methods, including physical constants and spectral data.
Synthesis of Exemplary Compounds
[0273] Unless otherwise indicated, starting materials are either commercially available or readily accessibly through laboratory synthesis by anyone reasonably familiar with the art. Described generally below, are procedures and general guidance for the synthesis of compounds as described generally and in subclasses and species herein.
Example 1: Synthesis of SAHP for Use as HDAC Inhibitors
[0274]
[0275] Described below is the synthesis of a SAHP, an ester-containing analog of SAHA (as shown in FIG. 12 ).
[0276] 3.86 g (24.2 mmol) O-benzylhydroxylamine hydrochloride and 13 mL (75 mmol) diisopropylethylamine were dissolved in 100 mL methylene chloride and cooled to 0° C. 5.00 g (24.2 mmol) methyl 8-chloro-8-oxooctanoate were dissolved in 10 mL methylene chloride and slowly added to the reaction mixture. The reaction mixture was stirred for 1 h at 0° C. and warmed to room temperature. After stirring for additional 12 h, 300 mL 0.5N HCl were added. The organic layer was separated and washed with brine and sat. bicarb. After drying over sodium sulfate, the organic solvent was removed under reduced pressure and the crude product was purified on silica (methylene chloride/methanol 12:1, rf=0.7) to yield the desired compound 1 as white solid (6.3 g, 89%).
[0277] 6.3 g (21.5 mmol) methyl ester 1 were dissolved in 200 mL methanol, followed by the addition of 50 mL 2N LiOH. The reaction mixture was heated to reflux for 1 h and cooled to room temperature. After addition of 100 mL 1N HCl and 200 mL water, the reaction mixture was extracted three times with 150 mL ethyl acetate. The combined organic layers were dried over sodium sulfate and the solvent was removed under reduced pressure to afford the carboxylic acid 2 pure and in quantitative yields as white solid
[0278] 140 mg carboxylic acid 2 (5 mmol), 56.5 mg phenol (6 mmol) and 113 mg dicyclohexylcarbodiimide (5.5 mmol) are mixed followed by the addition of 10 mL methylene chloride and 30 mg 4-Dimethylaminopyridine. The reaction mixture was stirred for 2 h and applied crude on a silica column followed by elution with haxanes/ethyl acetate (10-100% ethyl acetate). The desired phenol ester 3 was obtained as a white solid in 87% yield (155 mg).
[0279] 80 mg phenol ester 3 (0.225 mmol) are dissolved in methanol. A catalytical amount of palladium on charcoal (10%) was as added and hydrogen was bubbled through the reaction mixture. After 1 h hour no starting material was detectable by TLC. The reaction mixture was filtered through Celite and the solvent was removed under reduced pressure to yield the free hydroxamte SAHP as brownish solid in quantitative yields (59 mg). The crude product did not show any impurities as judged by LCMS and NMR.
Example 2: Biological Assay Procedures
[0280] Cell culture and Transfections.
[0281] TAg-Jurkat cells were transfected by electroporation with 5 μg of FLAG-epitope-tagged pBJ5 constructs for expression of recombinant proteins. Cells were harvested 48 h posttransfection.
[0282] HDAC assays.
[0283] [ 3 H]Acetate-incorporated histones were isolated from butyrate-treated HeLa cells by hydroxyapatite chromatography (as described in Tong, et al. Nature 1997, 395, 917-921.) Immunoprecipitates were incubated with 1.4 μg (10,000 dpm) histones for 3 h at 37° C. HDAC activity was determined by scintillation counting of the ethyl acetate-soluble [ 3 H]acetic acid (as described in Taunton, et al., Science 1996, 272, 408-411). Compounds were added in DMSO such that final assay concentrations were 1% DMSO. IC50s were calculated using Prism 3.0 software. Curve fitting was done without constraints using the program's Sigmoidal-Dose Response parameters. All data points were acquired in duplicate and IC50s are calculated from the composite results of at least two separate experiments.
Example 3: In Vivo Activity
[0284] Although a variety of methods can be utilized, one exemplary method by which the in vivo activity of the inventive compounds is determined is by subcutaneously transplanting a desired tumor mass in mice. Drug treatment is then initiated when tumor mass reaches approximately 100 mm 3 after transplantation of the tumor mass. A suitable composition, as described in more detail above, is then administered to the mice, preferably in saline and also preferably administered once a day at doses of 5, 10 and 25 mg/kg, although it will be appreciated that other doses can also be administered. Body weight and tumor size are then measured daily and changes in percent ratio to initial values are plotted. In cases where the transplanted tumor ulcerates, the weight loss exceeds 25-30% of control weight loss, the tumor weight reaches 10% of the body weight of the cancer-bearing mouse, or the cancer-bearing mouse is dying, the animal is sacrificed in accordance with guidelines for animal welfare.
Example 4: Assays to Identify Potential Antiprotozoal Compounds by Inhibition of Histone Deacetylase
[0285] As detailed in U.S. Pat. No. 6,068,987, inhibitors of histone deacetylases may also be useful as antiprotozoal agents. Described therein are assays for histone deacetylase activity and inhibition and describe a variety of known protozoal diseases. The entire contents of 6,068,987 are hereby incorporated by reference. | In recognition of the need to develop novel therapeutic agents, the present invention provides novel histone deacetylase inhibitors. These compounds include an ester bond making them sensitive to deactivation by esterases. Therefore, these compounds are particularly useful in the treatment of skin disorders. When the compounds reaches the bloodstream, an esterase or an enzyme with esterase activity cleaves the compound into biologically inactive fragments or fragments with greatly reduced activity Ideally these degradation products exhibit a short serum and/or systemic half-life and are eliminated rapidly. These compounds and pharmaceutical compositions thereof are particularly useful in treating cutaneous T-cell lymphoma, neurofibromatosis, psoriasis, hair loss, skin pigmentation, and dermatitis, for example. The present invention also provides methods for preparing compounds of the invention and intermediates thereto. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
This is a division of application Ser. No. 683,430, filed Apr. 10, 1991, now U.S. Pat. No. 5,420,261 which is a continuation in part application of Ser. No. 193,215, filed on May 11, 1988, now U.S. Pat. No. 5,059,795, which, in turn, is a continuation of application Ser. No. 928,937 filed on Nov. 10, 1986, abandoned.
BACKGROUND OF THE INVENTION AND RELATED ART STATEMENT
The present invention relates to a steel laminate gasket of a very thin type.
A conventional steel laminate gasket is constructed by laminating several plates, and is provided with a complicated sealing portion around a hole to be sealed. Consequently, it is difficult to manufacture a steel laminate gasket with light weight. Also, productivity of a steel laminate gasket is poor. As a result, a steel laminate gasket is expensive more than other gaskets.
In a small engine, a gasket must be light in weight and manufactured at a low cost. However, a conventional steel laminate gasket is heavy and expensive. Therefore, a conventional steel laminate gasket is not usually used for a small size engine.
In U.S. Pat. No. 4,834,399, a gasket formed of two plates has been proposed, wherein an area around a hole is sealed by one or two sealing means formed on the plates. The gasket can securely seal around the hole as intended. However, the gasket is not suitable for sealing around a hole where a large force is applied, e.g. an engine with high compression ratio.
Accordingly, one object of the present invention is to provide a steel laminate gasket for securely sealing around a hole, which is light in weight and simple in structure.
Another object of the invention is to provide a steel laminate gasket as stated above, which can securely seal around a hole without concentrating sealing pressure at one portion.
A further object of the invention is to provide a steel laminate gasket as stated above, which can be easily and economically manufactured.
Further objects and advantages of the invention will be apparent from the following description of the invention.
SUMMARY OF THE INVENTION
A metal laminate gasket of the invention is designed to be installed in an internal combustion engine having at least one hole therein. The gasket comprises a first metal plate and a second metal plate situated under the first metal plate.
The first plate includes a first hole corresponding to the hole of the engine, and first sealing means formed around the first hole to define and seal around the same. Further, the first plate includes a base section extending substantially throughout the entire area of the gasket, and an embossed portion situated between the first sealing means and the base section. When the gasket is tightened, the first sealing means does not deform, but the embossed portion resiliently deforms to seal around the first hole outside the first sealing means.
The second plate includes a second hole, and second sealing means formed around the second hole. The diameter of the second hole is larger than the diameter of the first sealing means to permit the second plate to pile over the base section without laying over the first sealing means. When the gasket is tightened, the second sealing means deforms to resiliently seal around the hole of the engine.
In the gasket of the invention, the first sealing means and the embossed portion formed on the first plate and the second sealing means formed on the second plate are radially spaced apart from each other relative to the hole of the engine. Therefore, when the gasket is tightened, surface pressure is not concentrated at one portion and can seal widely and securely around the hole.
The embossed portion is formed of an inclined wall disposed diagonally in the gasket. The height of the inclined wall from the lowest portion to the highest portion is greater than the thickness of the first sealing means.
The first sealing means is formed of a lower section and an upper section. The lower section is connected to the inclined wall, and the upper section is turned to be located above the lower section to form a solid portion.
Since the first sealing means around the hole of the engine constitutes the solid portion, the gasket can be tightened strongly without causing deformation of the engine parts or with very little deformation even if formed. The area around the hole of the engine is sealed non-resiliently by the solid portion of the first sealing means, and sealed resiliently by the embossed portion and the second sealing means.
The thickness of the first plate is made thicker than that of the second plate so that the solid portion is thicker than the total thickness of the gasket outside thereof. Therefore, the solid portion prevents the embossed portion and the second sealing means from completely compressed when the gasket is tightened. Namely, creep relaxation of the embossed portion and the second sealing means is prevented by the solid portion.
Preferably, an inner edge around the second hole of the second plate abuts against the inclined wall of the embossed portion when the first and second plates are assembled. Also, the second sealing means is formed of a bead or projection. As a result, when the gasket is tightened, the inner edge and the inclined wall push against each other by deformation of the bead or projection and the inclined wall to provide high sealing pressure at the inclined wall and the bead or projection.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a part of a first embodiment of a gasket of the invention;
FIG. 2 is an enlarged section view taken along line 2--2 in FIG. 1; and
FIGS. 3-7 are section views, similar to FIG. 2, of second to sixth embodiments of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2, a first embodiment A of a steel laminate gasket of the invention is shown. The gasket A is a cylinder head gasket, and includes cylinder bores Hc, water holes Hw, oil holes Ho and bolt holes Hb, as in the conventional gasket.
The sealing mechanism of the invention is applied around the cylinder bore Hc, but the same sealing mechanisms may be formed around other holes, or for other gaskets, such as a manifold gasket.
As shown in FIG. 2, the gasket A comprises an upper plate A10, and a lower plate A11 situated under the upper plate A10. The upper plate A10 includes a base section A10a extending substantially throughout the entire area of the gasket A, and an inclined wall A10b extending inwardly and downwardly from the base section A10a. A lower inner portion A10c of the upper plate A10 extends further inwardly from the inclined wall A10b, and an upper inner portion A10e is turned at a curved portion A10d and is situated above the lower inner portion A10c.
The cylinder bore Hc is defined by the curved portion A10d. Also, the upper and lower inner portions A10c, A10e constitute a solid portion around the cylinder bore Hc.
The height of the inclined wall A10b, i.e. the distance from the lower surface of the lower inner portion A10c to the upper surface of the base section A10a, is higher than the thickness of the solid portion, i.e. the distance from the lower surface of the lower inner portion A10c to the upper surface of the upper inner portion A10e. The inclined wall A10b constitutes an embossed portion.
The lower plate A11 is situated under the base section A10a of the upper plate A10 and extends substantially throughout the entire area of the gasket A. The lower plate A11 includes a hole A12, and a bead A11a around the hole A12. The size of the hole A12 must be larger than the size of the lower inner portion A10c.
In the gasket A, the size of the hole A12 is larger than the size of the inclined wall A10b so that an edge A11b of the lower plate A11 is located adjacent the inclined wall A10b. The thickness of the lower plate A11 is thinner than the thickness of the upper plate A10.
In the present invention, when the gasket A is tightened between a cylinder head and a cylinder block (both not shown), the inclined wall A10b and the bead A11a are compressed, but the upper and lower inner portions A10e, A10c form the solid portion and are not substantially compressed.
Therefore, the solid portion non-resiliently seals around the cylinder bore Hc, while the inclined wall A10b and the bead A11a resiliently seal around the cylinder bore Hc. Since the solid portion is formed around the cylinder bore Hc, when the gasket A is tightened, tightening pressure is not concentrated at one portion and is equally spread on the solid portion. Therefore, the gasket can be tightened at high tightening pressure without deformation of the cylinder bore Hc.
As explained before, the lower plate A11 is thinner than the upper plate A10. Therefore, the solid portion, i.e. the upper and lower inner portions A10e, A10c, is thicker than the total thickness of the upper and lower plates A10, A11. When the gasket A is tightened, therefore, the inclined wall A10b and the bead A11a are not completely compressed. As a result, creep relaxation of the inclined wall A10b and the bead A11a is prevented by the solid portion.
When the upper and lower plates A10, A11 are assembled, the edge A11b abuts against the inclined wall A10b. When the gasket A is tightened, since the solid portion is held between the cylinder head and cylinder block, the inclined wall A10b tries to move in the direction away from the cylinder bore Hc, while the edge A11b tries to move toward the cylinder bore Hc. Namely, when the gasket A is tightened, the edge A11b and the inclined wall A10b try to move in the opposite directions and push against each other. As a result, high surface pressure is formed at the inclined wall A10b and the bead A11a.
The gasket is sealed non-resiliently by the solid portion and resiliently by the inclined wall and the bead.
FIG. 3 shows a second embodiment B of the steel laminate gasket of the invention. The gasket B comprises an upper plate B10 with an inclined wall B10b and upper and lower inner portions B10e, B10c, and a lower plate B11, similar to the gasket A. In the gasket B, however, the lower plate B11 is provided with a bead B11a having a flat portion B11c and two side portions B11d.
In the gasket B, since the bead B11a has the flat portion B11c, when the gasket is tightened, surface pressure of the bead B11a is spread at the flat portion B11c, not concentrated at one portion. As a result, relatively high and wide surface pressure is obtained by the bead B11a.
In case a round bead, e.g. bead A11a, contacts an engine part made of an aluminum alloy and is tightened strongly, a dent may be formed on the engine part by the top of the bead. In the gasket B, since the bead B11a has the flat portion B11c, the engine part is not damaged by the bead. The gasket B operates as in the gasket A.
FIG. 4 shows a third embodiment C of the steel laminate gasket of the invention. The gasket C includes an upper plate C10 with an inclined wall C10b and upper and lower inner portions C10e, C10c, and a lower plate C11, similar to the gasket A. In the gasket C, however, the lower plate C11 is provided with an inclined wall C11a instead of a bead.
The inclined wall C11a is formed in case a regular bead can not be formed, such as there is not enough space for forming a bead in view of other member. When the gasket C is tightened, the inclined wall C11a deforms to seal around the cylinder bore Hc. The gasket C operates as in the gasket A.
FIG. 5 shows a fourth embodiment D of a steel laminate gasket of the invention. The gasket D includes an upper plate D10 having a base section D10a, an inclined wall D10b and upper and lower inner portions D10e, D10c, and a lower plate D11 with a bead D11a, similar to the gasket A.
In the gasket D, however, the upper plate D10 is further provided with a stepped portion D10f between the base section D10a and the inclined wall D10b. Namely, the base section D10a is located in a middle level of the inclined wall D10b to form the stepped portion D10f.
When the gasket D is tightened, the stepped portion D10f deforms as well as the inclined wall D10b and the bead D11a to seal around the cylinder bore Hc. Therefore, an area around the cylinder bore Hc is sealed more widely than the gasket A. The rest of the structure and operation of the gasket D is the same as the gasket A.
FIG. 6 shows a fifth embodiment E of a steel laminate gasket of the invention. The gasket E includes an upper plate E10 with an inclined wall E10b and upper and lower inner portions E10e, E10c, and a lower plate E11 with a bead E11a, similar to the gasket A.
In the gasket E, however, soft coatings E13 are further provided on both sides of the lower plate E10. Since the soft coating E13 are formed on the lower plate E11, which is not directly exposed to the cylinder bore Hc, the soft coating, such as gum or silicon resin, which is not strong against heat but effective to seal fluid may be used.
On the outer surface of the upper plate E10, a coating or plating which is strong against heat may be applied. The gasket E is especially useful for sealing around the fluid holes as well as the cylinder holes Hc.
FIG. 7 shows a sixth embodiment F of a steel laminate gasket of the invention. The gasket F includes an upper plate F10 with an inclined wall F10b and upper and lower inner portions F10e, F10c, and a lower plate F11 with a bead F11a, similar to the gasket A.
In the gasket F, however, the upper inner portion F10e is connected to the lower inner portion F10c through a curved portion F10d such that a space F14 is formed between the upper and lower inner portions F10e, F10c.
When the gasket F is tightened, the space F14 is diminished so that the upper and lower inner portions F10e, F10c substantially form a solid portion thereat. When the space F14 is diminished at the initial stage of compression of the gasket, the curved portion F10d is compressed together with the inclined wall F10b to thereby prevent movement of the inclined wall F10b in the direction of the cylinder bore Hc. As a result, the curved portion F10b and the inclined wall F10b securely seal around the cylinder bore Hc.
In the present invention, the gasket is provided with more than three sealing portions around a hole to be sealed, which are spaced apart from each other. Therefore, the gasket can be securely sealed.
In particular, the gasket can be tightened strongly without deformation of the hole to be sealed by the flat solid portion. The gasket can also provide high resilient surface pressure outside the solid portion by the inclined wall and the bead. The area around the hole can be sealed non-resiliently and resiliently.
While the invention has been explained with reference to the specific embodiments of the invention, the explanation is illustrative and the present invention is limited only by the appended claims. | A steel laminate gasket of the invention is installed in an internal combustion engine having at least one hole therein. The gasket comprises a first metal plate, and a second metal plate situated under the first metal plate. The first plate includes a first sealing device around a first hole to be sealed, and an embossed portion between the first sealing device and a base portion of the first plate. The second plate has a second hole larger than the first sealing device, and a second sealing device around the second hole. When the first and second plates are assembled, the second plate does not pile the first sealing device. The gasket is securely sealed by the combination of the first and second sealing devices and the embossed portion. | 5 |
This application a continuation of application Ser. No. 09/356,563, filed Jul. 19, 1999 which is a continuation of application Ser. No. 09/193,687 filed Feb. 18, 1999, now U.S. Pat. No. 6,023,907, which is a continuation of application Ser. No. 09/003,499 filed on Jan. 6, 1998, now U.S. Pat. No. 5,860,267, which is a divisional of application Ser. No. 08/436,224 filed on May 17, 1995, now U.S. Pat. No. 5,706,621 which is a 371 of PCT/SE94/00386, filed Apr. 29, 1994.
TECHNICAL FIELD
The invention generally relates to a system for providing a joint along adjacent joint edges of two building panels, especially floor panels.
More specifically, the joint is of the type where the adjacent joint edges together form a first mechanical connection locking the joint edges to each other in a first direction at right angles to the principal plane of the panels, and where a locking device forms a second mechanical connection locking the panels to each other in a second direction parallel to the principal plane and at right angles to the joint edges, the locking device comprising a locking groove which extends parallel to and spaced from the joint edge of one of the panels, and said locking groove being open at the rear side of this one panel.
The invention is especially well suited for use in joining floor panels, especially thin laminated floors. Thus, the following description of the prior art and of the objects and features of the invention will be focused on this field of use. It should however be emphasised that the invention is useful also for joining ordinary wooden floors as well as other types of building panels, such as wall panels and roof slabs.
BACKGROUND OF THE INVENTION
A joint of the aforementioned type is known e.g. from SE 450,141. The first mechanical connection is achieved by means of joint edges having tongues and grooves. The locking device for the second mechanical connection comprises two oblique locking grooves, one in the rear side of each panel, and a plurality of spaced-apart spring clips which are distributed along the joint and the legs of which are pressed into the grooves, and which are biased so as to tightly clamp the floor panels together. Such a joining technique is especially useful for joining thick floor panels to form surfaces of a considerable expanse.
Thin floor panels of a thickness of about 7-10 mm, especially laminated floors, have in a short time taken a substantial share of the market. All thin floor panels employed are laid as “floating floors” without being attached to the supporting structure. As a rule, the dimension of the floor panels is 200×1200 mm, and their long and short sides are formed with tongues and grooves. Traditionally, the floor is assembled by applying glue in the groove and forcing the floor panels together. The tongue is then glued in the groove of the other panel. As a rule, a laminated floor consists of an upper decorative wear layer of laminate having a thickness of about 1 mm, an intermediate core of particle board or other board, and a base layer to balance the construction. The core has essentially poorer properties than the laminate, e.g. in respect of hardness and water resistance, but it is nonetheless needed primarily for providing a groove and tongue for assemblage. This means that the overall thickness must be at least about 7 mm. These known laminated floors using glued tongue-and-groove joints however suffer from several inconveniences.
First, the requirement of an overall thickness of at least about 7 mm entails an undesirable restraint in connection with the laying of the floor, since it is easier to cope with low thresholds when using thin floor panels, and doors must often be adjusted in height to come clear of the floor laid. Moreover, manufacturing costs are directly linked with the consumption of material.
Second, the core must be made of moisture-absorbent material to permit using water-based glues when laying the floor. Therefore, it is not possible to make the floors thinner using so-called compact laminate, because of the absence of suitable gluing methods for such non-moisture-absorbent core materials.
Third, since the laminate layer of the laminated floors is highly wear-resistant, tool wear is a major problem when working the surface in connection with the formation of the tongue.
Fourth, the strength of the joint, based on a glued tongue-and-groove connection, is restricted by the properties of the core and of the glue as well as by the depth and height of the groove. The laying quality is entirely dependent on the gluing. In the event of poor gluing, the joint will open as a result of the tensile stresses which occur e.g. in connection with a change in air humidity.
Fifth, laying a floor with glued tongue-and-groove joints is time-consuming, in that glue must be applied to every panel on both the long and short sides thereof.
Sixth, it is not possible to disassemble a glued floor once laid, without having to break up the joints. Floor panels that have been taken up cannot therefore be used again. This is a drawback particularly in rental houses where the flat concerned must be put back into the initial state of occupancy. Nor can damaged or worn-out panels be replaced without extensive efforts, which would be particularly desirable on public premises and other areas where parts of the floor are subjected to great wear.
Seventh, known laminated floors are not suited for such use as involves a considerable risk of moisture penetrating down into the moisture-sensitive core.
Eighth, present-day hard, floating floors require, prior to laying the floor panels on hard subfloors, the laying of a separate underlay of floor board, felt, foam or the like, which is to damp impact sounds and to make the floor more pleasant to walk on. The placement of the underlay is a complicated operation, since the underlay must be placed in edge-to-edge fashion. Different under-lays affect the properties of the floor.
There is thus a strongly-felt need to overcome the above-mentioned drawbacks of the prior art. It is however not possible simply to use the known joining technique with glued tongues and grooves for very thin floors, e.g. with floor thicknesses of about 3 mm, since a joint based on a tongue-and-groove connection would not be sufficiently strong and practically impossible to produce for such thin floors. Nor are any other known joining techniques usable for such thin floors. Another reason why the making of thin floors from e.g. compact laminate involves problems is the thickness tolerances of the panels, being about 0.2-0.3 mm for a panel thickness of about 3 mm. A 3-mm compact laminate panel having such a thickness tolerance would have, if ground to uniform thickness on its rear side, an unsymmetrical design, entailing the risk of bulging. Moreover, if the panels have different thicknesses, this also means that the joint will be subjected to excessive load.
Nor is it possible to overcome the above-mentioned problems by using double-adhesive tape or the like on the undersides of the panels, since such a connection catches directly and does not allow for subsequent adjustment of the panels as is the case with ordinary gluing.
Using U-shaped clips of the type disclosed in the above-mentioned SE 450,141, or similar techniques, to overcome the drawbacks discussed above is no viable alternative either. Especially, biased clips of this type cannot be used for joining panels of such a small thickness as 3 mm. Normally, it is not possible to disassemble the floor panels without having access to their undersides. This known technology relying on clips suffers from the additional drawbacks:
Subsequent adjustment of the panels in their longitudinal direction is a complicated operation in connection with laying, since the clips urge the panels tightly against each other.
Floor laying using clips is time-consuming.
This technique is usable only in those cases where the floor panels are resting on underlying joists with the clips placed therebetween. For thin floors to be laid on a continuous, flat supporting structure, such clips cannot be used.
The floor panels can be joined together only at their long sides. No clip connection is provided on the short sides.
Technical Problems and Objects of the Invention
A main object of the invention therefore is to provide a system for joining together building panels, especially floor panels for hard, floating floors, which allows using floor panels of a smaller overall thickness than present-day floor panels.
A particular object of the invention is to provide a panel-joining system which
makes it possible in a simple, cheap and rational way to provide a joint between floor panels without requiring the use of glue, especially a joint based primarily only on mechanical connections between the panels;
can be used for joining floor panels which have a smaller thickness than present-day laminated floors and which have, because of the use of a different core material, superior properties than present-day floors even at a thickness of 3 mm;
makes it possible between thin floor panels to provide a joint that eliminates any unevennesses in the joint because of thickness tolerances of the panels;
allows joining all the edges of the panels;
reduces tool wear when manufacturing floor panels with hard surface layers;
allows repeated disassembly and reassembly of a floor previously laid, without causing damage to the panels, while ensuring high laying quality;
makes it possible to provide moisture-proof floors;
makes it possible to obviate the need of accurate, separate placement of an underlay before laying the floor panels; and
considerably cuts the time for joining the panels.
These and other objects of the invention are achieved by means of a panel-joining system having the features recited in the appended claims.
Thus, the invention provides a system for making a joint along adjacent joint edges of two building panels, especially floor panels, in which joint:
the adjacent joint edges together form a first mechanical connection locking the joint edges to each other in a first direction at right angles to the principal plane of the panels, and
a locking device arranged on the rear side of the panels forms a second mechanical connection locking the panels to each other in a second direction parallel to the principal plane and at right angles to the joint edges, said locking device comprising a locking groove which extends parallel to and spaced from the joint edge of one of said panels, termed groove panel, and which is open at the rear side of the groove panel, said system being characterised in
that the locking device further comprises a strip integrated with the other of said panels, termed strip panel, said strip extending throughout substantially the entire length of the joint edge of the strip panel and being provided with a locking element projecting from the strip, such that when the panels are joined together, the strip projects on the rear side of the groove panel with its locking element received in the locking groove of the groove panel,
that the panels, when joined together, can occupy a relative position in said second direction where a play exists between the locking groove and a locking surface on the locking element that is facing the joint edges and is operative in said second mechanical connection,
that the first and the second mechanical connection both allow mutual displacement of the panels in the direction of the joint edges, and
that the second mechanical connection is so conceived as to allow the locking element to leave the locking groove if the groove panel is turned about its joint edge angularly away from the strip.
The term “rear side” as used above should be considered to comprise any side of the panel located behind/underneath the front side of the panel. The opening plane of the locking groove of the groove panel can thus be located at a distance from the rear surface of the panel resting on the supporting structure. Moreover, the strip, which in the invention extends throughout substantially the entire length of the joint edge of the strip panel, should be considered to encompass both the case where the strip is a continuous, uninterrupted element, and the case where the “strip” consists in its longitudinal direction of several parts, together covering the main portion of the joint edge.
It should also be noted (i) that it is the first and the second mechanical connection as such that permit mutual displacement of the panels in the direction of the joint edges, and that (ii) it is the second mechanical connection as such that permits the locking element to leave the locking groove if the groove panel is turned about its joint edge angularly away from the strip. Within the scope of the invention, there may thus exist means, such as glue and mechanical devices, that can counteract or prevent such displacement and/or upward angling.
The system according to the invention makes it possible to provide concealed, precise locking of both the short and long sides of the panels in hard, thin floors. The floor panels can be quickly and conveniently dis-assembled in the reverse order of laying without any risk of damage to the panels, ensuring at the same time a high laying quality. The panels can be assembled and dis-assembled much faster than in present-day systems, and any damaged or worn-out panels can be replaced by taking up and re-laying parts of the floor.
According to an especially preferred embodiment of the invention, a system is provided which permits precise joining of thin floor panels having, for example, a thickness of the order of 3 mm and which at the same time provides a tolerance-independent smooth top face at the joint. To this end, the strip is mounted in an equalising groove which is countersunk in the rear side of the strip panel and which exhibits an exact, predetermined distance from its bottom to the front side of the strip panel. The part of the strip projecting behind the groove panel engages a corresponding equalising groove, which is countersunk in the rear side of the groove panel and which exhibits the same exact, predetermined distance from its bottom to the front side of the groove panel. The thickness of the strip then is at least so great that the rear side of the strip is flush with, and preferably projects slightly below the rear side of the panels. In this embodiment, the panels will always rest, in the Joint, with their equalising grooves on a strip. This levels out the tolerance and imparts the necessary strength to the joint. The strip transmits horizontal and upwardly-directed forces to the panels and downwardly-directed forces to the existing subfloor.
Preferably, the strip may consist of a material which is flexible, resilient and strong, and can be sawn. A preferred strip material is sheet aluminium. In an aluminium strip, sufficient strength can be achieved with a strip thickness of the order of 0.5 mm.
In order to permit taking up previously laid, joined floor panels in a simple way, a preferred embodiment of the invention is characterised in that when the groove panel is pressed against the strip panel in the second direction and is turned anglularly away from the strip, the maximum distance between the axis of rotation of the groove panel and the locking surface of the locking groove closest to the joint edges is such that the locking element can leave the locking groove without contacting the locking surface of the locking groove. Such a disassembly can be achieved even if the aforementioned play between the locking groove and the locking surface is not greater than 0.2 mm.
According to the invention, the locking surface of the locking element is able to provide a sufficient locking function even with very small heights of the locking surface. Efficient locking of 3-mm floor panels can be achieved with a locking surface that is as low as 2 mm. Even a 0.5-mm-high locking surface may provide sufficient locking. The term “locking surface” as used herein relates to the part of the locking element engaging the locking groove to form the second mechanical connection.
For optimal function of the invention, the strip and the locking element should be formed on the strip panel with high precision. Especially, the locking surface of the locking element should be located at an exact distance from the joint edge of the strip panel.
Furthermore, the extent of the engagement in the floor panels should be minimised, since it reduces the floor strength.
By known manufacturing methods, it is possible to produce a strip with a locking pin, for example by extruding aluminium or plastics into a suitable section, which is thereafter glued to the floor panel or is inserted in special grooves. These and all other traditional methods do however not ensure optimum function and an optimum level of economy. To produce the joint system according to the invention, the strip is suitably formed from sheet aluminium, and is mechanically fixed to the strip panel.
The laying of the panels can be performed by first placing the strip panel on the subfloor and then moving the groove panel with its long side up to the long side of the strip panel, at an angle between the principal plane of the groove panel and the subfloor. When the joint edges have been brought into engagement with each other to form the first mechanical connection, the groove panel is angled down so as to accommodate the locking element in the locking groove.
Laying can also be performed by first placing both the strip panel and the groove panel flat on the subfloor and then joining the panels parallel to their principal planes while bending the strip downwards until the locking element snaps up into the locking groove. This laying technique enables in particular mechanical locking of both the short and long sides of the floor panels. For example, the long sides can be joined together by using the first laying technique with downward angling of the groove panel, while the short sides are subsequently joined together by displacing the groove panel in its longitudinal direction until its short side is pressed on and locked to the short side of an adjacent panel in the same row.
In connection with their manufacture, the floor panels can be provided with an underlay of e.g. floor board, foam or felt. The underlay should preferably cover the strip such that the joint between the underlays is offset in relation to the joint between the floor panels.
The above and other features and advantages of the invention will appear from the appended claims and the following description of embodiments of the invention.
The invention will now be described in more detail hereinbelow with reference to the accompanying drawing Figures.
DESCRIPTION OF DRAWING FIGURES
FIGS. 1 a and 1 b schematically show in two stages how two floor panels of different thickness are joined together in floating fashion according to a first embodiment of the invention.
FIGS. 2 a-c show in three stages a method for mechanically joining two floor panels according to a second embodiment of the invention.
FIGS. 3 a-c show in three stages another method for mechanically joining the floor panels of FIGS. 2 a-c.
FIGS. 4 a and 4 b show a floor panel according to FIGS. 2 a-c as seen from below and from above, respectively.
FIG. 5 illustrates in perspective a method for laying and joining floor panels according to a third embodiment of the invention.
FIG. 6 shows in perspective and from below a first variant for mounting a strip on a floor panel.
FIG. 7 shows in section a second variant for mounting a strip on a floor panel.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIGS. 1 a and 1 b , to which reference is now made, illustrate a first floor panel 1 , hereinafter termed strip panel, and a second floor panel 2 , hereinafter termed groove panel. The terms “strip panel” and “groove panel” are merely intended to facilitate the description of the invention, the panels 1 , 2 normally being identical in practice. The panels 1 and 2 may be made from compact laminate and may have a thickness of about 3 mm with a thickness tolerance of about ±0.2 mm. Considering this thickness tolerance, the panels 1 , 2 are illustrated with different thicknesses (FIG. 1 b ), the strip panel 1 having a maximum thickness (3.2 mm) and the groove panel 2 having a minimum thickness (2.8 mm).
To enable mechanical joining of the panels 1 , 2 at opposing joint edges, generally designated 3 and 4 , respectively, the panels are provided with grooves and strips as described in the following.
Reference is now made primarily to FIGS. 1 a and 1 b , and secondly to FIGS. 4 a and 4 b showing the basic design of the floor panels from below and from above, respectively.
From the joint edge 3 of the strip panel 1 , i.e. the one long side, projects horizontally a flat strip 6 mounted at the factory on the underside of the strip panel 1 and extending throughout the entire joint edge 3 . The strip 6 , which is made of flexible, resilient sheet aluminium, can be fixed mechanically, by means of glue or in any other suitable way. In FIGS. 1 a and 1 b , the strip 6 is glued, while in FIGS. 4 a and 4 b it is mounted by means of a mechanical connection, which will be described in more detail hereinbelow.
Other strip materials can be used, such as sheets of other metals, as well as aluminium or plastics sections. Alternatively, the strip 6 may be integrally formed with the strip panel 1 . At any rate, the strip 6 should be integrated with the strip panel 1 , i.e. it should not be mounted on the strip panel 1 in connection with laying. As a non-restrictive example, the strip 6 may have a width of about 30 mm and a thickness of about 0.5 mm.
As appears from FIGS. 4 a and 4 b , a similar, although shorter strip 6 ′ is provided also at one short side 3 ′ of the strip panel 1 . The shorter strip 6 ′ does however not extend throughout the entire short side 3 ′ but is otherwise identical with the strip 6 and, therefore, is not described in more detail here.
The edge of the strip 6 facing away from the joint edge 3 is formed with a locking element 8 extended throughout the entire strip 6 . The locking element 8 has a locking surface 10 facing the joint edge 3 and having a height of e.g. 0.5 mm. The locking element 8 is so designed that when the floor is being laid and the strip panel 2 of FIG. 1 a is pressed with its joint edge 4 against the joint edge 3 of the strip panel 1 and is angled down against the subfloor 12 according to FIG. 1 b , it enters a locking groove 14 formed in the underside 16 of the groove panel 2 and extending parallel to and spaced from the joint edge 4 . In FIG. 1 b , the locking element 8 and the locking groove 14 together form a mechanical connection locking the panels 1 , 2 to each other in the direction designated D 2 . More specifically, the locking surface 10 of the locking element 8 serves as a stop with respect to the surface of the locking groove 14 closest to the joint edge 4 .
When the panels 1 and 2 are joined together, they can however occupy such a relative position in the direction D 2 that there is a small play A between the locking surface 10 and the locking groove 14 . This mechanical connection in the direction D 2 allows mutual displacement of the panels 1 , 2 in the direction of the joint, which considerably facilitates the laying and enables joining together the short sides by snap action.
As appears from FIGS. 4 a and 4 b , each panel in the system has a strip 6 at one long side 3 and a locking groove 14 at the other long side 4 , as well as a strip 6 ′ at one short side 3 ′ and a locking groove 14 ′ at the other short side 4 ′.
Furthermore, the joint edge 3 of the strip panel 1 has in its underside 18 a recess 20 extending throughout the entire joint edge 3 and forming together with the upper face 22 of the strip 6 a laterally open recess 24 . The joint edge 4 of the groove panel 2 has in its top side 26 a corresponding recess 28 forming a locking tongue 30 to be accommodated in the recess 24 so as to form a mechanical connection locking the joint edges 3 , 4 to each other in the direction designated D 1 . This connection can be achieved with other designs of the joint edges 3 , 4 , for example by a bevel thereof such that the joint edge 4 of the groove panel 2 passes obliquely in underneath the joint edge 3 of the strip panel 1 to be locked between that edge and the strip 6 .
The panels 1 , 2 can be taken up in the reverse order of laying without causing any damage to the joint, and be laid again.
The strip 6 is mounted in a tolerance-equalising 10 groove 40 in the underside 18 of the strip panel 1 adjacent the joint edge 3 . In this embodiment, the width of the equalising groove 40 is approximately equal to half the width of the strip 6 , i.e. about 15 mm. By means of the equalising groove 40 , it is ensured that there will always exist between the top side 21 of the panel 1 and the bottom of the groove 40 an exact, predetermined distance E which is slightly smaller than the minimum thickness (2.8 mm) of the floor panels 1 , 2 . The groove panel 2 has a corresponding tolerance-equalising surface or groove 42 in the underside 16 of the joint edge 4 . The distance between the equalising surface 42 and the top side 26 of the groove panel 2 is equal to the aforementioned exact distance E. Further, the thickness of the strip 6 is so chosen that the underside 44 of the strip is situated slightly below the undersides 18 and 16 of the floor panels 1 and 2 , respectively. In this manner, the entire joint will rest on the strip 6 , and all vertical downwardly-directed forces will be efficiently transmitted to the subfloor 12 without any stresses being exerted on the joint edges 3 , 4 . Thanks to the provision of the equalising grooves 40 , 42 , an entirely even joint will be achieved on the top side, despite the thickness tolerances of the panels 1 , 2 , without having to perform any grinding or the like across the whole panels. Especially, this obviates the risk of damage to the bottom layer of the compact laminate, which might give rise to bulging of the panels.
Reference is now made to the embodiment of FIGS. 2 a-c showing in a succession substantially the same laying method as in FIGS. 1 a and 1 b . The embodiment of FIGS. 2 a-c primarily differs from the embodiment of FIGS. 1 a and 1 b in that the strip 6 is mounted on the strip panel 1 by means of a mechanical connection instead of glue. To provide this mechanical connection, illustrated in more detail in FIG. 6, a groove 50 is provided in the underside 18 of the strip panel 1 at a distance from the recess 24 . The groove 50 may be formed either as a continuous groove extending throughout the entire length of the panel 1 , or as a number of separate grooves. The groove 50 defines, together with the recess 24 , a dovetail gripping edge 52 , the underside of which exhibits an exact equalising distance E to the top side 21 of the strip panel 1 . The aluminium strip 6 has a number of punched and bent tongues 54 , as well as one or more lips 56 which are bent round opposite sides of the gripping edge 52 in clamping engagement therewith. This connection is shown in detail from below in the perspective view of FIG. 6 .
Alternatively, a mechanical connection between the strip 6 and the strip panel 1 can be provided as illustrated in FIG. 7 showing in section a cut-away part of the strip panel 1 turned upside down. In FIG. 7, the mechanical connection comprises a dovetail recess 58 in the underside 18 of the strip panel 1 , as well as tongues/lips 60 punched and bent from the strip 6 and clamping against opposing inner sides of the recess 58 .
The embodiment of FIGS. 2 a-c is further characterised in that the locking element 8 of the strip 6 is designed as a component bent from the aluminium sheet and having an operative locking surface 10 extending at right angles up from the front side 22 of the strip 6 through a height of e.g. 0.5 mm, and a rounded guide surface 34 facilitating the insertion of the locking element 8 into the locking groove 14 when angling down the groove panel 2 towards the subfloor 12 (FIG. 2 b ), as well as a portion 36 which is inclined towards the subfloor 12 and which is not operative in the laying method illustrated in FIGS. 2 a-c.
Further, it can be seen from FIGS. 2 a-c that the joint edge 3 of the strip panel 1 has a lower bevel 70 which cooperates during laying with a corresponding upper bevel 72 of the joint edge 4 of the groove panel 2 , such that the panels 1 and 2 are forced to move vertically towards each other when their joint edges 3 , 4 are moved up to each other and the panels are pressed together horizontally.
Preferably, the locking surface 10 is so located relative to the joint edge 3 that when the groove panel 2 , starting from the joined position in FIG. 2 c , is pressed horizontally in the direction D 2 against the strip panel 1 and is turned angularly up from the strip 6 , the maximum distance between the axis of rotation A of the groove panel 2 and the locking surface 10 of the locking groove is such that the locking element 8 can leave the locking groove 14 without coming into contact with it.
FIGS. 3 a - 3 b show another joining method for mechanically joining together the floor panels of FIGS. 2 a-c . The method illustrated in FIGS. 3 a-c relies on the fact that the strip 6 is resilient and is especially useful for joining together the short sides of floor panels which have already been joined along one long side as illustrated in FIGS. 2 a-c . The method of FIGS. 3 a-c is performed by first placing the two panels 1 and 2 flat on the subfloor 12 and then moving them horizontally towards each other according to FIG. 3 b . The inclined portion 36 of the locking element 8 then serves as a guide surface which guides the joint edge 4 of the groove panel 2 up on to the upper side 22 of the strip 6 . The strip 6 will then be urged downwards while the locking element 8 is sliding on the equalising surface 42 . When the joint edges 3 , 4 have been brought into complete engagement with each other horizontally, the locking element 8 will snap into the locking groove 14 (FIG. 3 c ), thereby providing the same locking as in FIG. 2 c . The same locking method can also be used by placing, in the initial position, the joint edge 4 of the groove panel with the equalising groove 42 on the locking element 10 (FIG. 3 a ). The inclined portion 36 of the locking element 10 then is not operative. This technique thus makes it possible to lock the floor panels mechanically in all directions, and by repeating the laying operations the whole floor can be laid without using any glue.
The invention is not restricted to the preferred embodiments described above and illustrated in the drawings, but several variants and modifications thereof are conceivable within the scope of the appended claims. The strip 6 can be divided into small sections covering the major part of the joint length. Further, the thickness of the strip 6 may vary throughout its width. All strips, locking grooves, locking elements and recesses are so dimensioned as to enable laying the floor panels with flat top sides in a manner to rest on the strip 6 in the joint. If the floor panels consist of compact laminate and if silicone or any other sealing compound, a rubber strip or any other sealing device is applied prior to laying between the flat projecting part of the strip 6 and the groove panel 2 and/or in the recess 26 , a moisture-proof floor is obtained.
As appears from FIG. 6, an underlay 46 , e.g. of floor board, foam or felt, can be mounted on the underside of the panels during the manufacture thereof. In one embodiment, the underlay 46 covers the strip 6 up to the locking element 8 , such that the joint between the underlays 46 becomes offset in relation to the joint between the joint edges 3 and 4 .
In the embodiment of FIG. 5, the strip 6 and its locking element 8 are integrally formed with the strip panel 1 , the projecting part of the strip 6 thus forming an extension of the lower part of the joint edge 3 . The locking function is the same as in the embodiments described above. On the underside 18 of the strip panel 1 , there is provided a separate strip, band or the like 74 extending throughout the entire length of the joint and having, in this embodiment, a width covering approximately the same surface as the separate strip 6 of the previous embodiments. The strip 74 can be provided directly on the rear side 18 or in a recess formed therein (not shown), so that the distance from the front side 21 , 26 of the floor to the rear side 76 , including the thickness of the strip 74 , always is at least equal to the corresponding distance in the panel having the greatest thickness tolerance. The panels 1 , 2 will then rest, in the joint, on the strip 74 or only on the undersides 18 , 16 of the panels, if these sides are made plane.
When using a material which does not permit downward bending of the strip 6 or the locking element 8 , laying can be performed in the way shown in FIG. 5. A floor panel 2 a is moved angled upwardly with its long side 4 a into engagement with the long side 3 of a previously laid floor panel 1 while at the same time a third floor panel 2 b is moved with its short side 4 b ′ into engagement with the short side 3 a ′ of the upwardly-angled floor panel 2 a and is fastened by angling the panel 2 b downwards. The panel 2 b is then pushed along the short side 3 a ′ of the upwardly-angled floor panel 2 a until its long side 4 b encounters the long side 3 of the initially-laid panel 1 . The two upwardly-angled panels 2 a and 2 b are therefore angled down on to the subfloor 12 so as to bring about locking.
By a reverse procedure the panels can be taken up in the reverse order of laying without causing any damage to the joint, and be laid again.
Several variants of preferred laying methods are conceivable. For example, the strip panel can be inserted under the groove panel, thus enabling the laying of panels in all four directions with respect to the initial position. | The invention relates to a system for laying and mechanically joining building panels, especially thin, hard, floating floors. Adjacent joint edges ( 3, 4 ) of two panels ( 1, 2 ) engage each other to provide a first mechanical connection locking the joint edges ( 3,4 ) in a first direction (D1) perpendicular to the principal plane of the panels. In each joint, there is further provided a strip ( 6 ) which is integrated with one joint edge ( 3 ) and which projects behind the other joint edge ( 4 ). The strip ( 6 ) has an upwardly protruding locking element ( 8 ) engaging in a locking groove ( 14 ) in the rear side ( 16 ) of the other joint edge ( 4 ) to form a second mechanical connection locking the panels ( 1, 2 ) in a second direction (D2) parallel to the principal plane of the panels and at right angles to the joint. Both the first and the second mechanical connection allow mutual displacement of joined panels ( 1, 2 ) in the direction of the joint. | 4 |
This is a continuation of application Ser. No. 393,603, filed June 30, 1982 and now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention concerns methods and apparatus for performing porosimetric analysis on solid samples.
2. Description of the Prior Art
According to known techniques, porosimetric analyses are performed by a process in which a solid sample is introduced into a test vessel together with a quantity of a suitable liquid, such as mercury. The liquid is then subjected to an increasing pressure. The volumetric variations of the liquid which is due to the penetration of the same into the pores of the sample is then detected as pressure varies.
By this known process, it is possible to trace a pressure-volume mercury curve, on the basis of which, and according to a known formula, it is possible to obtain a size distribution of the sample's pores, and information on the same sample.
During this test very high pressure values (around 2000 atmospheres) are reached and it is clear that at the end of same it is necessary to lower pressure to values substantially equal to the ambient ones.
During this pressure reduction, the test liquid, in particular mercury, obviously tends to come out of some of the pores which it had penetrated during pressure increase. In particular it tends to come out of the pores which present an open configuration, while, on the contrary, it tends to remain inside pores which present an almost closed configuration. Therefore, a lowering pressure-volume mercury curve is obtained which presents, together with the pressure-volume mercury curve traced during the pressure increase phase, a hysteretic course, allowing indications on the shape of the sample pores to be obtained. However, these indications are relatively fragmentary and partial, in that they are obtained up to now in correspondence to one or more pressure values, practically only in correspondence to the point corresponding to the return to ambient values as well as to the point of maximum pressure value.
SUMMARY OF THE INVENTION
It has now been proved, after tests carried out by the Applicant, that much wider and much more reliable information can be obtained if the decreasing pressure curve is obtained following a law predetermined in time, in particular at constant speed, or in any way such as to allow control on the rate of pressure decrease.
Therefore, the present invention relates to a method for porosimetric analyses of the above described type, wherein the stage of pressure reduction is performed according to a law predetermined in time and wherein the volume variations of the concerned liquid, in particular mercury, are detected, when pressure decreases according to said law. This law advantageously considers a pressure reduction at constant speed, as obtained by detecting the pressure of the liquid concerned, by taking a derivative of same with respect to time and by controlling a pressure exhaust device as a function of the instant value of the derivative.
The invention also concerns apparatus to perform said method and comprising, in a known circuit for pressure increase in a porosimeter having a low pressure circuit with a fluid feeding a pressure multiplier and then a high pressure circuit: detection means for high pressure; a device to correlate said detected high pressure with time; and control means for an exhaust valve operating on said low pressure circuit, under the control of said device. Said valve is preferably a needle valve with cone-shaped shutter and cylindrical seat.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatical view showing a pressurization circuit of a porosimeter, including an apparatus for the control of pressure exhaust, according to the present invention.
FIG. 2 is an example of a pressure-volume diagram which can be obtained in a complete porosimetric analysis when carried out by means of the apparatus of FIG. 1.
FIGS. 3 and 4 are axial cross-sections, angularly offset to each other and showing a pressure reduction valve for the apparatus of FIG. 1.
FIG. 5 is a partial cross-section of the same valve, corresponding to that of FIG. 4 but illustrating another position of the valve stem.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, apparatus for porosimetric detections comprises, as already known, a test apparatus 10, including a vessel 12 in which a solid sample 14 is placed, immersed in a liquid, usually mercury 16, the meniscus 18 of which is in a zone of reduced diameter at the mouth of vessel 12. The vessel 12 is immersed in a different liquid, for instance an oil 20 which acts on the mercury meniscus 18 as well, said oil coming from a tank 22 through two valves 24 and 26 placed on two serially connected ducts 28 and 30. The duct 28 is connected, on the side opposite to the tank 22, to the smaller cylinder 32 of a pressure multiplier 34, of known type. The large piston 36 is placed in a cylinder 38, which is fed through a duct 40 by a pump 42 sucking oil or another suitable fluid from a tank 44 through a tube 46. By pumping the low pressure fluid from pump 42 to cylinder 38, said piston 36 is moved and a pressure increase in the circuit downstream of cylinder 32 is obtained, with a pressure increase of oil 20 in the test apparatus 10. Said pressure increase compels the mercury 16 to penetrate into the pores of sample 14, with a related variation, in particular a decrease in the level of meniscus 18, which occurs and is detected as variations in pressure values, and may be correlated to trace a curve 48 (FIG. 2). From curve 48 it is possible to obtain, in a known way, sufficient data to determine some important porosimetric properties of sample 14. To obtain analytical results, it is known that pressure exercised in the high pressure circuit must reach very high values, about 2000 atmospheres, while the low pressure circuit operates taking into account that said multiplier 34 gives pressure ratios of the order of 1/100, i.e. within limits around 20 atmospheres.
The pressure reduction in the high pressure circuit, from said maximum value of about 2000 atmospheres to the ambient value, is performed by means of valve 50 acting on the low pressure circuit, in particular in a by-pass duct 52 which is connected to the tube sections 40 and 46, respectively downstream and upstream of said pump 42.
The pressure reduction involves significant importance for porosimetric analyses and particularly for the determination of the pore shape and related distribution, when the pressure reduction is performed according to a predetermined law in time. A curve of the type as shown by 54 in FIG. 2 may then be obtained, wherein said curve, together with curve 48, has a general shape of the hysteretic type. In FIG. 2, the value of 56 obviously corresponds to the amount of mercury 16 remaining in the pores of sample 14.
To perform said pressure reduction according to a predetermined variation law in time, and in particular, as preferred, at a constant pressure reduction rate, the invention proposes a pressure transducer 58 which detects at 60 the pressure in said high pressure circuit and transforms the obtained values into signals. These signals are transmitted along a line 62 to a differentiator circuit or means for differentiating which provides an output signal representing the derivative of the input signal with respect to time or a representative rate signal. This circuit, as shown by 64 in FIG. 1 is conventional and may take any of the well known forms of this conventional class of device. For instance, a classical type of differentiator circuit shown and described at Page 15 (FIG. 22) of the "Handbook of Operational Amplifier Applications", compiled by the Applications Engineering Department of Burr Brown Research Corporation, Tucson, Ariz., First Edition (second printing), Copyright 1963, may be employed. The output signal therefrom is transmitted at 66 to a window comparator 68. The window comparator 68, which may be conventional, compares said output signal with two fixed signals or reference levels, respectively, corresponding to the allowed maximum and minimum pressure reduction speeds or windows established. These two signals of the comparator 68 can be modified in a known way, either by widening or reducing the window or difference between them, or mainly by modifying their value in order to correspondingly modify the present values of pressure reduction speed. When said comparator 68 ascertains that the signal coming from line 66 exceeds or is smaller than predetermined maximum or minimum limits, respectively, either one or the other of two signals, schematically indicated by 70 and 72, is emitted as an error signal to cause the actuation of motor 74 in one direction or the other to adjust valve 50 and bring the rate of pressure reduction within the window established. The window comparator 68 may take the form of a pair of threshold detectors or comparators wherein the maximum or minimum limits are the threshold or reference values set. Such a conventional arrangement is shown, for instance, by the dual level comparator illustrated on Page 141 of the "Guidebook of Electronic Circuits", John Markus, McGraw-Hill Book Company, Copyright 1974. If this configuration were employed a separate output from each comparator would be directly utilized as outputs 70 and 72. The maximum value (V H ) and the minimum value (V L ) or limits may be selected such that the ratio of V H to V L equals a constant, for instance a value of 1.2 may be selected.
The valve 50 is described in greater detail in FIGS. 3 and 5 and as shown therein takes the form of a needle-type valve with a cone-shaped stem and a cylindrical seat. The stem cone angle is chosen so as to obtain a good balance between the need for quick actuation and valve precision. It is obvious that, if the cone angle is small, the response time will be slower, but greater precision will be achieved.
The illustrated valve essentially comprises a body 80 in which an input passage 82 and an exhaust passage 84 are established for the fluid employed in the low pressure circuit. The passages 82 and 84 are connected to a duct 86 where a cylindrical seat 88 is provided. A cone-shaped body 90 of the valve acts in said seat and is mounted at the end of a stem 92 capable of axially moving with respect to the cylindrical seat 88. FIGS. 3, 4, and 5 respectively show the valve stem 92 in its end positions, i.e. completely closed in FIGS. 3 and 4 and completely open in FIG. 5. However, in general, the valve is designed to operate in a position in which the cone-shaped section 90 of same only partially penetrates into the cylindrical seat 88. This leaves a small fluid blow-by area, corresponding to the desired pressure reduction speed in the low pressure circuit, and consequently, in the high pressure circuit.
The stem 92 is mounted in a rotationally free, but axially integral way inside a bushing 96, which is threaded on the outside in 98 to meet a corresponding threading of a nut screw provided in an insert 100 which in turn is connected to the body 80 of the valve by threading in 102. The insert 100 is housed in a seat 104 of the valve body with pneumatic sealing in 106 and its bottom is crossed by the stem 92. Sealing is obtained by a gasket 108 blocked by a bushing 110. The bushing 96 is integral, for instance in a single piece, with a gear wheel 112 placed in a zone outside the valve body, but protected towards the outside by a covering 114. The gear wheel 112 meshes with a pinion 116 mounted on a shaft 118 placed in parallel to the stem 92. As clearly shown in the drawing, the pinion 116 has such an axial length as to allow the gear wheel 112 to slide in the same direction along the same axis, as the bushing 96 goes up and down when the latter is turned owing to its meshing with the threading 98. The shaft 118 can be rotated manually, by means of a control handle 120, acting in emergency, but it is usually controlled in its rotations by a geared motor 122 which is conventional, corresponding to the motor means 74 of FIG. 1. Obviously, said geared motor can rotate in both directions to cause rotations in both directions of the pinion 116 and of the wheel 112, as well as of the bushing 96, with corresponding upward and downward axial movements of same together with the stem 92 which opens or closes the valve seat 88. The axial movements of stem 92 control the passage area of the low pressure fluid between the inlet 82 and outlet 84. The movements of stem 92 are controlled, as previously seen, by a detection performed on the high pressure circuit so as to maintain the pressure reduction speed within given limits. In this way it is possible to obtain a pressure reduction speed in the high pressure circuit which ranges from values of 1 bar/sec to values of 20 bar/sec, with a single type of valve design, that is with the same exhaust valve and therefore with the same analytical equipment.
With reference to FIGS. 4 and 5, the stem 92 is provided outside the valve body 80, with a plate 124 which moves parallely to the stem itself out of the valve body 80 and bears means for delimiting the run of stem 92, between the valve's completely closed position and completely open position. Said means can be constituted by an opening 126, which cooperates with two detectors 128 and 130, for instance photodiodes, to determine the positions of maximum closure (FIG. 4) and maximum opening (FIG. 5). Said valve has proved to be particularly precise and of particularly quick actuation, so that it is possible to consider that a pressure reduction in the high pressure circuit is performed, by said control, at a constant speed, in a way that the curve 54 of FIG. 2 can be traced and related conclusions can be drawn from it about further porosimetric properties of sample 14, nondetectable from curve 48 alone.
As it will be clear to those skilled in the art, the invention can be carried-out in different ways, all coming within the scope of the present invention. | A method for performing porosimetric analyses and apparatus therefor are disclosed. In particular, a method for performing porosimetric anaylses by the so-called mercury method is disclosed, wherein volumetric variations of mercury placed in a vessel are recorded. These variations are due to mercury penetration into the pores of a solid sample placed in the vessel under the mercury pressure variations. In the method disclosed, additional porosimetric information is obtained by reducing the pressure from a maximum value as a predetermined function of time. For example, the pressure reduction can be at a constant rate. Simultaneously, volume variations of the mercury exiting the sample pores are detected as the pressure decreases. This additional detection, when performed in relation to and/or in addition to the traditional measurement during pressure increase, provides a pressure/volume mercury curve which gives further data on the porosimetric characteristics of the sample, in particular related to the shape of the pores in the sample. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to a hot-working die steel for use as die-casting molds. More particularly, the invention relates to a hot-working die steel for die-casting which inhibits the cracking from a water-cooling hole, which is a major cause of serious cracks in die-casting molds, and is capable of coping with a higher cycle speed in the production of die-casting products. The hot-working die steel for die-casting of the invention can be advantageously used as a material for aluminum die-casting molds.
BACKGROUND OF THE INVENTION
[0002] Aluminum die-casting molds have hitherto had a problem that cracks generate at the cavity surface due to thermal fatigue (i.e., heat check). This heat check is a phenomenon in which the cavity surface, when sprinkled with cooling water after mold opening, comes to have an tensile stress due to a temperature difference between the rapidly cooled cavity surface and inner parts in a heated state, and the thermal fatigue resulting from repetitions of this stress generation causes cracks at the cavity surface.
[0003] It is said that it is advantageous to heighten the hardness of the mold for diminishing the heat check.
[0004] On the other hand, there recently has been a desire for a reduction in cycle time (higher cycle speed) in the production of aluminum die-casting products. For the purpose of reducing a mold closing time in order to realize that desire, the water cooling of an aluminum cast in a mold tends to be enhanced. Specifically, this enhancement of water cooling is accomplished by disposing a water-cooling hole in a position closer to the cavity surface. In this case, the thermal stress generating at the surface of the water-cooling hole during the casting of an aluminum product is increased and the phenomenon in which a crack generates from the water-cooling hole becomes problematic.
[0005] Such a crack generating from a water-cooling hole is not attributable only to the thermal stress repeatedly imposed during casting but is thought to be a delayed-fracture phenomenon including a combination of cracking caused by thermal stress and stress corrosion cracking caused by rust generating on the surface of the water-cooling hole.
[0006] The higher the hardness of a mold, the more the cracking from the water-cooling hole is apt to occur. Consequently, it is advantageous to reduce the hardness of a mold for inhibiting such cracking from the water-cooling hole.
[0007] Namely, to increase mold hardness is advantageous for diminishing the heat check but is disadvantageous for diminishing cracking from a water-cooling hole, whereas to reduce mold hardness is advantageous for diminishing cracking from a water-cooling hole but is disadvantageous for diminishing the heat check, resulting in impaired heat check resistance.
[0008] From the standpoint of inhibiting the cracking from a water-cooling hole, it is desirable to regulate the mold hardness to HRC 45 to 40.
[0009] Hot-working die steels of the 5Cr type represented by JIS-SKD61 have been mainly used for current aluminum die-casting molds. In recent years, the use hardness thereof has been increasing so as to inhibit the heat check generating at the cavity surface, and the risk of cracking from the water-cooling hole in the mold has been increasing with the trend toward a higher cycle speed in the production of aluminum die-casting products.
[0010] In the case of the JIS-SKD61, this steel contains about 0.4% of C and the hardness of the steel in a quenched state is, for example, about HRC 53.
[0011] For reducing the hardness thereof to HRC 45 or lower for the purpose of inhibiting cracking from a water-cooling hole, it is necessary to conduct annealing at a high temperature of 600° C. or above. However, when annealing at such a high temperature is conducted, the corrosion resistance of the steel decreases considerably.
[0012] This material, which contains Cr in an amount of about 5%, in itself is a material having excellent corrosion resistance. However, when this steel is annealed at a temperature as high as 600° C. or above, most of the Cr contained therein separates out as a Cr carbide due to this high-temperature annealing. Accordingly, the Cr contained in the steel thus comes not to contribute to an improvement in corrosion resistance.
[0013] In any event, the hot-working die steels presently in main use as aluminum die-casting molds, which are represented by JIS-SKD61, are ineffective in satisfactorily overcoming the problem concerning cracking from a water-cooling hole.
[0014] It is thought that an effective measure in satisfactorily overcoming each of the problem concerning cracking from a water-cooling hole and the problem concerning heat check at the cavity surface is to prevent rusting in the water-cooling hole and to reduce the hardness of that inner part of the mold in which the water-cooling hole is present, as well as to increase the hardness of the mold cavity surface where a heat check may generate. However, no material satisfying such properties has been provided yet.
[0015] Incidentally, reference document 1 shown below discloses an invention concerning a technique in which the inner circumferential surface of the water-cooling hole of a die-casting mold is regulated so as to have a lower hardness than the mold surface to thereby reconcile the prevention of water-cooling hole cracking and the heat check resistance of the mold surface.
[0016] The steel disclosed in this reference document 1 is produced by regulating JIS-SKD61, which has been used hitherto, so as to have a high hardness by quenching and tempering and then regulating the surface of the water-cooling hole so as to have a low hardness by local tempering with induction heating, burner heating, laser heating, or the like.
[0017] All the methods disclosed in this reference document 1 necessitate local heating, and have a problem that the shape of the water-cooling hole is limited, for example, that the diameter of the water-cooling hole should be a size which enables burner insertion.
[0018] Reference Document 1: JP-A-6-315753
SUMMARY OF THE INVENTION
[0019] The present invention has been achieved under the circumstances described above. An object of the invention is to provide a hot-working die steel for die-casting which has excellent heat check resistance and can satisfactorily inhibit cracking from a water-cooling hole.
[0020] The present inventors have made eager investigation to examine the problem. As a result, it has been found that the foregoing objects can be achieved by the following hot-working die steels for die-casting. With this finding, the present invention is accomplished.
[0021] The present invention is mainly directed to the following items.
[0022] 1. A hot-working die steel for die-casting obtainable by quenching a steel comprising, in terms of % by mass,
[0023] C: 0.1 to 0.3%,
[0024] Si: 0.1 to 1.5%,
[0025] Mn: 0.3 to 2%,
[0026] Cr: 6 to 12%,
[0027] P: 0.05% or less,
[0028] S: 0.01% or less,
[0029] Mo: 1 to 3%,
[0030] V: 0.5 to 1.5%,
[0031] s-Al: 0.005 to 0.025%,
[0032] N: 0.005 to 0.025%, and
[0033] O: 0.005% or less,
[0034] with the remainder being Fe and
[0035] inevitable impurities,
[0000] followed by tempering the steel at a temperature of 500° C. or lower.
[0036] 2. The hot-working die steel for die-casting according to item 1, which further comprises at least one member selected from the group consisting of, in terms of % by mass,
[0037] Ni: 2% or less, and
[0038] Cu: 1% or less.
[0039] 3. The hot-working die steel for die-casting according to item 1 or 2, which further comprises, in terms of % by mass,
[0040] C: 5% or less.
[0041] 4. The hot-working die steel for die-casting according to any one of items 1 to 3, which further comprises at least one member selected from the group consisting of, in terms of % by mass,
[0042] Ti: 0.2% or less,
[0043] Zr: 0.2% or less, and
[0044] Nb: 0.2% or less.
[0045] The hot-working die steel for die-casting of the invention has a reduced C content and, on the other hand, has high and optimized Cr and Mo contents. Accordingly, the steel of the invention, when used as a die-casting mold, can effectively inhibit cracking from the water-cooling hole and can impart excellent heat check resistance to the die-casting mold. The hot-working die steel for die-casting of the invention can be advantageously used especially as a material for aluminum die-casting molds.
[0046] Cr is known as an element which improves corrosion resistance. In ordinary JIS-SKD61, however, the Cr for improving corrosion resistance separates out disadvantageously as a carbide during the heat treatment for obtaining a use hardness because this steel is tempered at a temperature as high as 600° C. or above as described hereinabove. Accordingly, the effect of the Cr is almost lost. On the other hand, when the tempering temperature is lowered to such a degree that Cr carbide separation does not occur, the steel comes to have an exceedingly high hardness of 50 HRC or above. When such a steel is used as a die-casting mold, cracking from the water-cooling hole is apt to occur.
[0047] A target hardness may be obtained through tempering at a low temperature of 500° C. or below by reducing the C content. In this case, however, the hardness of the cavity surface also decreases to cause a problem that heat check resistance becomes poor.
[0048] Herein, in the hot-working die steel for die-casting of the invention, the C content is reduced and Mo is added in an appropriate amount.
[0049] By reducing the C content, a hardness of HRC 45 or below, which is less apt to result in cracking from a water-cooling hole, can be obtained through tempering at a low temperature of 500° C. or below.
[0050] Furthermore, by the addition of an appropriate amount of Mo, the mold cavity surface can be partly increased in hardness by utilizing the heat transferred from the melt (e.g., aluminum melt) during die-casting when this steel is used as a die-casting mold.
[0051] Specifically, the Mo added separates out as a carbide when the mold is used for the casing of a die-casting product and the cavity surface is heated by the heat transferred from the melt (about 600-650° C. in the case of aluminum melt) to thereby serve to partly heighten the hardness of the cavity surface.
[0052] Namely, the hot-working die steel for die-casting of the invention has an effect that the hardness of the cavity surface increases by means of age hardening during the use of the mold. Due to this effect, heat check in the cavity surface can be satisfactorily inhibited.
[0053] Namely, in the hot-working die steel for die-casting of the invention, the phenomenon in which, when the steel is used as a die-casting mold, the cavity surface thereof undergoes age hardening due to the heat transferred from the melt can be ingeniously utilized. As a result, it is possible to obtain a mold which retains a low hardness in inner parts thereof but has a partly increased hardness in the cavity surface. In this respect, the hot-working die steel for die-casting of the invention has an excellent effect over conventional ones.
[0054] Moreover, Cr as a corrosion-resistant element has been added in a larger amount in the invention than in JIS-SKD61. In the invention, annealing is conducted at a temperature as low as 500° C. or below after a quenching treatment. Accordingly, the Cr added does not separate out as a carbide but is in the state of being a solid solution in the matrix to effectively serve to improve the corrosion resistance of the steel. Namely, due to this corrosion-resistance-improving function of the Cr, when the hot-working die steel for die-casting of the invention is used as a die-casting mold, rusting in the water-cooling hole is inhibited and the cracking from the water-cooling hole, which is caused by the rusting, is satisfactorily inhibited.
[0055] Furthermore, when the hot-working die steel for die-casting of the invention is used as a die-casting mold, the cavity surface of the mold undergoes secondary hardening (age hardening) due to the separation of a Mo carbide, whereby it hardens to come to have a hardness of HRC 45 or higher, at which heat check resistance can be secured.
[0056] Next, reasons for the limitation of each chemical component in the invention will be described below in detail. Hereinafter, “%” means “% by mass”.
[0057] C: 0.1 to 0.3%
[0058] C is an element necessary for securing hardness and wearing resistance, which are important mold performances.
[0059] Ordinary hot-working die steels contain C in an amount of about 0.4%. In the invention, however, the C content is lower than in the ordinary hot-working die steels so that a hardness of HRC 45 or lower can be obtained through low-temperature tempering at 500° C. or lower. The range thereof is 0.1 to 0.3%, preferably 0.15 to 0.25%.
[0060] Si: 0.1 to 1.5%
[0061] Si is an element necessary as a deoxidizing element in steelmaking.
[0062] Furthermore, by increasing the content thereof, machinability and resistivity to temper softening can be improved.
[0063] However, excessively large addition amount thereof results in reduced impact value toughness. Consequently, the range of the addition amount thereof is 0.1 to 1.5%, preferably 0.1 to 0.5%.
[0064] Mn: 0.3 to 2%
[0065] Mn is a component necessary for securing hardenability and hardness. The addition amount thereof id set at 0.3% or larger.
[0066] On the other hand, when Mn is added excessively, hardenability becomes too high and there are some cases where quenching yields a large amount of residual γ to reduce the impact value or where annealing does not result in a reduction in hardness. Consequently, the upper limit thereof is set at 2%. The upper limit of the addition amount of Mn is preferably set at 1%.
[0067] Cr: 6 to 12%
[0068] Cr is an element which improves hardenability and also improves the corrosion resistance of a water-cooling hole.
[0069] For obtaining the effect of improving corrosion resistance, it is necessary to add Cr in an amount of 6% or larger. It is preferred to add Cr in an amount of 8% or larger.
[0070] However, addition in an excessively large amount reduces resistivity to temper softening and also reduces mold performances. Therefore, the upper limit thereof is set at 12%. Further, it is preferred that the upper limit of the content of Cr be set at 10%.
[0071] P: ≦0.05%
[0072] P is an element which is preferably diminished because it reduces impact value. When the steel contains it inevitably, it is preferred to diminish the content thereof to 0.05% or below.
[0073] S: ≦0.01%
[0074] S is an element which is preferably diminished because it forms MnS to reduce impact value.
[0075] When the steel contains it inevitably, it is preferred to diminish the content thereof to 0.01% or below.
[0076] Mo: 1 to 3%
[0077] Mo is necessary for strengthening the matrix and improving the wearing resistance through carbide formation and also for securing hardenability.
[0078] Furthermore, when the hot-working die steel for die-casting of the invention is used as a die-casting mold, this Mo carbide separates out due to the heat transferred from the melt (around 600° C. in the case of aluminum melt) to thereby heighten the hardness of the mold.
[0079] Although the mold hardness after quenching and subsequent tempering has been set at HRC 45 or lower in the invention in order to prevent cracking from the water-cooling hole, the temperature of the cavity surface rises during die-casting (around 600° C. in the case of aluminum die-casting) and a hardness of HRC 45 or higher can be obtained. Thus, heat check resistance can be improved.
[0080] For obtaining such an effect, it is necessary to add Mo in an amount of 1% or larger and it is preferred to add Mo in an amount of 1.5% or larger.
[0081] However, even when it is added excessively, the effect is saturated and such an excessive addition is economically disadvantageous. The upper limit of the addition is therefore set at 3%. It is preferred that the upper limit of the addition amount of Mo be set at 2.5%.
[0082] V: 0.5 to 1.5%
[0083] V is an element which forms a carbide and separates out during tempering to thereby strengthen the matrix and improve wearing resistance.
[0084] Furthermore, during heating for quenching, it forms a fine carbide and this has the effect of inhibiting crystal grain enlargement to thereby inhibit impact value decrease.
[0085] For obtaining such an effect, it is necessary to add V in an amount of 0.5% or larger.
[0086] On the other hand, in a case where V is added excessively, it yields coarse carbonitride crystals during solidification to reduce toughness. Consequently, the upper limit of the addition amount of V is set at 1.5%. It is preferred that the upper limit of the addition amount of V be set at 1%.
[0087] s-Al: 0.005 to 0.025%
[0088] Al not only functions as a deoxidizing element during steelmaking, but is an element which combines with the N in the steel and finely disperses as a nitride to inhibit crystal grain enlargement during heating for quenching.
[0089] For obtaining such effects, it is necessary to add Al in an amount of 0.005% or larger.
[0090] However, even when it is added in a large amount, the effect is saturated.
[0091] Consequently, the upper limit of the addition amount thereof is set at 0.025%.
[0092] N: 0.005 to 0.025%
[0093] N is an element which combines with the Al and V in the steel to form nitrides. The nitrides finely disperse to thereby inhibit crystal grain enlargement during heating for quenching. N is hence an element effective for preventing impact value decrease.
[0094] For obtaining such an effect, it is necessary to add N in an amount of 0.005% or larger.
[0095] However, even when it is added in a large amount, the effect is saturated.
[0096] Consequently, the upper limit of the addition amount thereof is set at 0.025%.
[0097] O: ≦ 0 . 005 %
[0098] O forms oxide inclusions to decrease impact value. For inhibiting impact value decrease, it is necessary to reduce the content of O to 0.005% or lower.
[0099] Ni: ≦2%, Cu: ≦1%
[0100] Since Ni enhances hardenability and are thus effective in toughening the matrix, it can be added according to need.
[0101] However, even when these elements are added excessively, the effects are saturated and the excessive addition thereof is economically disadvantageous. The upper limits of the addition amount thereof are hence set at 2% and 1%, respectively.
[0102] Co: ≦5%
[0103] Co is an element which improves strength through solid-solution strengthening. It can be added according to need.
[0104] However, even when it is added excessively, the effect is saturated and the excessive addition thereof is economically disadvantageous. Consequently, the upper limit of the addition amount thereof is set at 5%.
[0105] Ti: ≦0.2%, Zr: ≦0.2%, Nb: ≦0.2%
[0106] These are elements which form Ti(CN), Zr(CN), Nb(CN), and composite carbonitrides thereof and finely separate out to inhibit crystal grain enlargement during heating for quenching. When it is desired to form fine crystal grains to secure toughness, these elements can be added according to need.
[0107] However, in case where those elements are added excessively, they separate out as coarse carbonitride crystals during solidification to reduce rather than increase impact value. Consequently, the upper limits of the addition amount thereof are set at 0.2%, respectively.
[0108] Furthermore, in the case where those elements are added in combination, it is preferred that the total amount thereof be 0.5% or smaller.
DETAILED DESCRIPTION OF THE INVENTION
[0109] Embodiments of the present invention will be described below in detail.
[0110] The present invention is now illustrated in greater detail with reference to Steels of the invention and Comparative Steels, but it should be understood that the present invention is not to be construed as being limited thereto.
[0111] Steels respectively having the compositions shown in Table 1 each were melted in a 150-kg vacuum high-frequency induction furnace. Each ingot thus obtained was forged at 1,200° C. into a square bar having a section of 60 mm×60 mm.
[0112] This square bar was cut into a length of 500 mm, subsequently heated to 1,030° C., and then subjected to oil quenching.
[0113] Thereafter, tempering was conducted twice under the conditions with a temperature of 450° C. and a period of 1 h. Each square bar which had been tempered was subjected to each of a measurement of the hardness of a ¼ H part (a part located midway between the surface and the central part), a Charpy impact test in the T direction (width direction for the square bar) using a 2-mm U-notch test piece, and a corrosion test in which a block of 10 mm×10 mm×10 mm was cut out of the ¼ H part, the surface thereof was polished with an emery paper, and this block was then wholly immersed in 20° C. industrial water for 24 h and examined for rusting.
[0114] In the evaluation of corrosion resistance, ones which suffered no rusting are rated as A and ones which suffered rusting are rated as B.
[0115] Furthermore, for the purpose of simulating a heat history in repetitions of the casting of an aluminum die-casting product, each of the square bars which had been tempered at 450° C. was subjected to repeated 1,000 cycles each including heating from room temperature to 650° C. by high-frequency heating, holding at this temperature for 4 seconds, and subsequent water cooling. Thereafter, the surface hardness thereof was measured.
[0116] The results of these evaluations are shown in Table 2.
[0000]
TABLE 1
Composition (mass %)
No.
C
Si
Mn
P
S
Cr
Mo
V
s-Al
N
O
Others
Invention
1
0.12
0.1
0.42
0.008
0.002
8.2
2.8
0.6
0.015
0.01
0.003
Steel
2
0.2
0.3
0.45
0.012
0.002
9
2.5
0.8
0.02
0.012
0.002
3
0.18
0.5
0.8
0.01
0.005
11.3
2
1.1
0.005
0.022
0.004
4
0.23
0.3
1.2
0.024
0.008
6.5
2.8
1.4
0.008
0.008
0.002
5
0.28
0.8
0.6
0.003
0.009
10.1
1.6
0.9
0.013
0.005
0.003
6
0.2
1.3
1.4
0.018
0.001
8.8
1.8
0.8
0.022
0.008
0.001
Ni: 1%
7
0.2
0.3
0.5
0.009
0.002
9.2
2.3
0.6
0.021
0.011
0.002
Ni: 0.5%, Cu: 0.5%
8
0.21
0.25
0.45
0.003
0.002
9
2.5
0.7
0.018
0.009
0.003
Ni: 0.7%, Co: 2%
9
0.18
0.3
0.6
0.007
0.002
9.5
2.2
0.6
0.011
0.021
0.002
Co: 4%, Ti: 0.05%
10
0.22
0.22
0.65
0.031
0.001
10.1
2.3
0.55
0.016
0.023
0.002
Zr: 0.1%, Nb: 0.1%
11
0.18
0.25
0.67
0.021
0.001
8.9
2.5
0.61
0.02
0.018
0.003
Co: 1%, Zr: 0.2%,
Nb: 0.05%
Comparative
a
0.05
0.2
0.52
0.015
0.002
8.3
2.3
0.62
0.021
0.011
0.002
Steel
b
0.38
0.21
0.48
0.011
0.002
9.1
2.3
0.65
0.022
0.015
0.002
c
0.2
2
0.45
0.012
0.002
9.2
2.5
0.6
0.018
0.012
0.002
d
0.2
0.2
2.5
0.011
0.002
8.9
2.4
0.61
0.019
0.011
0.003
e
0.2
0.2
0.5
0.08
0.001
9.1
2.5
0.6
0.021
0.011
0.002
f
0.2
0.21
0.5
0.012
0.05
9
2.5
0.61
0.02
0.01
0.002
g
0.21
0.22
0.5
0.011
0.001
5.1
2.3
0.6
0.021
0.01
0.002
h
0.19
0.21
0.45
0.012
0.002
13.5
2.4
0.61
0.019
0.009
0.003
i
0.21
0.25
0.44
0.009
0.002
9
0.6
0.6
0.02
0.009
0.002
j
0.2
0.21
0.48
0.011
0.002
9.1
2.1
0.3
0.015
0.008
0.001
k
0.19
0.22
0.51
0.011
0.002
9.3
2.4
0.6
0.003
0.007
0.002
l
0.21
0.3
0.52
0.012
0.001
9
2.3
0.7
0.012
0.002
0.002
m
0.19
0.29
0.46
0.011
0.001
9
2.3
0.6
0.012
0.009
0.008
Conventional
A
0.38
1
0.45
0.011
0.001
5.5
1.2
0.85
0.02
0.012
0.002
Steel
[0000]
TABLE 2
450° Tempering
Hardness after
Impact
repetitions
Hardness
value
Corrosion
of 650°
No.
(HRC)
(J/cm 2 )
resistance
heating (HRC)
Invention
1
40
52
A
46
Steel
2
42
48
A
48
3
41
50
A
46
4
43
46
A
49
5
44
45
A
48
6
42
48
A
47
7
42
48
A
48
8
42
49
A
47
9
41
50
A
46
10
43
48
A
48
11
41
48
A
47
Com-
a
36
58
A
42
parative
b
53
21
A
48
Steel
c
42
25
A
48
d
42
23
A
48
e
42
18
A
47
f
42
15
A
48
g
42
49
B
48
h
42
21
A
48
i
42
48
A
44
j
42
32
A
47
k
41
33
A
47
l
42
28
A
48
m
40
30
A
48
Conventional
A
53
18
B
47
Steel
* Corrosion resistance: A . . . no rusting, B . . . rusting occurred
[0117] Furthermore, a steel obtained by heating Invention Steel No. 2 shown in Table 1 to 1,030° C. and subsequently subjecting it to oil quenching and then to tempering twice under the conditions with a temperature of 450° C. and a period of 1 h, one obtained by heating Conventional Steel A to 1,030° C. and subsequently subjecting it to oil quenching and then to tempering twice under the conditions with a temperature of 450° C. and a period of 1 h, and one obtained by subjecting Conventional Steel A to tempering twice under the conditions with a temperature of 630° C. and a period of 1 h were respectively evaluated for delayed-fracture resistance as an index to receptivity to cracking from a water-cooling hole.
[0118] Here, the evaluation of delayed-fracture resistance was conducted in the following manner.
[0119] Namely, industrial water was dropped (in order to cause rusting) onto the notched part of a test piece having a 0.1-R annular notch, and the relationship between flexural stress and fracture time was examined.
[0120] The delayed-fracture resistance was evaluated by comparing in the ratio of static flexural stress (0-h rupture stress) to the stress causing rupture at 200 h.
[0121] Furthermore, 10,000 cycles each including heating from room temperature to 650° C., holding at this temperature for 4 seconds, and subsequent water cooling were repeatedly conducted. Thereafter, the length of the heat crack generated at the surface was measured and evaluated as an index to heat check resistance.
[0122] The results of these evaluations are shown in Table 3.
[0123] In Table 3, the desired value of delayed-fracture resistance was set at 0.7 or higher.
[0000]
TABLE 3
Heat check
Delayed-fracture
Tempering
resistance
resistance
temperature
Hardness
Length of largest
Proportion of 200-h
No.
(° C.)
(HRC)
heat crack (μm)
rupture stress
2
450
42
120
0.98
A
450
53
123
0.65
630
42
253
0.91
[0124] As the results given in Table 2 show, Invention Steels No. 1 to No. 11 have hardnesses of HRC 40 to 44 after the tempering at 450° C. and have hardnesses after the repetitions of heating at 650° C. of HRC 46 to 49. The hardnesses thereof have increased.
[0125] Furthermore, since the tempering is low-temperature tempering at 450° C., almost no Cr carbide has separated out. Each steel shows satisfactory corrosion resistance.
[0126] In contrast, Comparative Steel a has a C content of 0.05%, which is lower than the lower limit of 0.1% in the invention, and hence has a hardness after the 450° C. tempering as low as HRC 36. The hardness thereof after the repetitions of heating at 650° C. also is as low as HRC 42. It has poor heat check resistance.
[0127] Comparative Steel b conversely has a C content of 0.38%, which is higher than the upper limit of 0.3% in the invention, and hence has a hardness after the 450° C. tempering as high as HRC 53. It has a low impact value.
[0128] Comparative Steel c has a Si content of 2%, which is higher than the upper limit of 1.5% in the invention. It has a low impact value.
[0129] Comparative Steel d has a Mn content of 2.5%, which is higher than the upper limit of 2% in the invention. It has a low impact value.
[0130] Comparative Steel e has a content of P as an impurity of 0.08%, which is higher than the upper limit of 0.05% in the invention. This steel also has a low impact value.
[0131] Furthermore, Comparative Steel f has a content of S also as an impurity of 0.05%, which is higher than the upper limit of 0.01% in the invention, and hence has a low impact value.
[0132] Comparative Steel g has a Cr content of 5.1%, which is lower than the lower limit of 6% in the invention, and hence has low corrosion resistance.
[0133] Comparative Steel h conversely has a Cr content of 13.5%, which is higher than the upper limit of 12% in the invention, and hence has a low impact value.
[0134] Comparative Steel i has a Mo content of 0.6%, which is lower than the lower limit of 1% in the invention. Because of this, even through the repetitions of heating at 650° C., the hardness has not increased sufficiently. This means that heat check resistance is insufficient.
[0135] Comparative Steel j has a V content of 0.3%, which is lower than the lower limit of 0.5% in the invention. Because of this, crystal grain enlargement has occurred and the steel has a low impact value.
[0136] Comparative Steel k has an s-Al content of 0.003%, which is lower than the lower limit of 0.005% in the invention. Because of this, crystal grain enlargement has occurred and the steel has a low impact value.
[0137] Comparative Steel l has an N content of 0.002%, which is lower than the lower limit of 0.005% in the invention. Because of this, crystal grain enlargement has occurred in this case also and the steel has a low impact value.
[0138] Comparative Steel m has an O content of 0.008%, which is higher than the upper limit of 0.005% in the invention. Because of this, the steel contains a larger amount of inclusions and has a low impact value.
[0139] Next, Conventional Steel A is JIS-SKD61 and has a hardness after the 450° C. tempering of HRC 53. The hardness thereof after the repetitions of heating at 650° C. has decreased to HRC 47. It is poor also in corrosion resistance.
[0140] Next, in Table 3, Invention Steel No. 2 has a low hardness after the low-temperature tempering at 450° C. However, this steel is equal in heat check resistance and superior in delayed-fracture resistance to the high-hardness material obtained by tempering Conventional Steel A at 450° C.
[0141] Furthermore, as compared with the steel having the same hardness obtained by the 630° C. high-temperature tempering of Conventional Steel A, Invention Steel No. 2 has higher corrosion resistance and better heat check resistance because of the low-temperature tempering.
[0142] It can be seen as demonstrated above that the steels of the invention have both of the property of inhibiting cracking from a water-cooling hole and heat check resistance; these two properties have hitherto being inconsistent with each other.
[0143] While the present invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.
[0144] The present application is based on Japanese Patent Application No. 2005-346156 filed on Nov. 30, 2005, and the contents thereof are incorporated herein by reference. | The invention provides a hot-working die steel for die-casting obtainable by quenching a steel comprising, in terms of % by mass, C: 0.1 to 0.3%, Si: 0.1 to 1.5%, Mn: 0.3 to 2%, Cr: 6 to 12%, P: 0.05% or less, S: 0.01% or less, Mo: 1 to 3%, V: 0.5 to 1.5%, s-Al: 0.005 to 0.025%, N: 0.005 to 0.025%, and O: 0.005% or less, with the remainder being Fe and inevitable impurities, followed by tempering the steel at a temperature of 500° C. or lower. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from Provisional application No. 61/146,795 filed 23 Jan. 2009, incorporated in its entirety herein by reference.
STATEMENT REGARDING RIGHTS TO INVENTION MADE UNDER FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT
[0002] This invention was made with Government support under Contract DE-AC06-76RLO1830 awarded by the U.S. Department of Energy. The Government has certain rights in the invention.
FIELD OF THE INVENTION
[0003] The invention is in the field of ion mobility spectrometry (IMS), specifically differential IMS or field asymmetric waveform IMS (FAIMS) and hybrid analytical platforms involving this method.
BACKGROUND OF THE INVENTION
[0004] In Field asymmetric waveform ion mobility spectrometry (FAIMS), also termed differential mobility spectrometry (DMS), ions are separated in gases by the difference of mobility at two substantially unequal electric field intensities, E (R. Guevremont. J. Chromatogr. A 2004, 1058, 3). The gas pressure is typically ambient (atmospheric), though operation at reduced pressure is possible and may be advantageous (E. G. Nazarov, S. L. Coy, E. V. Krylov, R. A. Miller, G. A. Eiceman. Anal. Chem. 2006, 78, 7697). FIG. 1 a shows a flow-driven FAIMS stage 50 , where ions are filtered in the analytical gap 12 between two electrodes 10 , one carrying a periodic asymmetric high-voltage waveform V(t) 18 with the amplitude termed the “dispersion voltage” (DV) and the same or other electrode carrying a fixed “compensation voltage” (CV) 8 . At any given CV, only species with a particular difference between the mobility at “high” and “low” E in the positive and negative V(t) segments remains in equilibrium and is most likely to pass the gap. In the FAIMS systems reduced to practice so far, ions are moved through the gap by a steady laminar flow of carrier gas 4 . Besides stand-alone use, FAIMS is increasingly employed to filter ions prior to mass spectrometry (MS) and/or drift tube ion mobility spectrometry (DTIMS) analyses (R. W. Purves, R. Guevremont. Anal. Chem. 1999, 71, 2346; K. Tang, F. Li, A. A. Shvartsburg, E. F. Strittmatter, R. D. Smith. Anal. Chem. 2005, 77, 6381). Ions can be propelled through the gap by a relatively weak electric field (E L ) along it instead of the flow (U.S. Pat. No. 7,456,390, U.S. Pat. No. 7,547,879). In FIG. 1 b , such a longitudinal field-driven FAIMS stage 50 is shown with E L along the analytical gap 12 established by segmenting both electrodes 10 and applying a voltage ladder to the segments. Alternatively, the field E L may be created by maintaining a voltage drop across contiguous electrodes with substantial ohmic resistance, as is known in the art of DTIMS (M. Kwasnik, K. Fuhrer, M. Gonin, K. Barbeau, F. M. Fernandez. Anal. Chem. 2007, 79, 7782) and has been considered for FAIMS (U.S. Pat. No. 7,498,570).
[0005] As a filtering technique, FAIMS inherently involves ion losses. Hence, to maximize the sensitivity of multidimensional analytical platforms comprising FAIMS, one needs to switch it “off”, i.e., to employ the other stage(s) without FAIMS filtering. In particular, the ability to use FAIMS/MS systems for MS-only analyses is usually desired. As FAIMS normally precedes MS or other stage(s) in hybrid systems, this means effectively transmitting ions to those stage(s) through or around the FAIMS unit. In the current art, effective use of such other stage(s) without FAIMS requires physically removing the FAIMS unit and reassembling the instrument in a new configuration. This process calls for trained personnel, testing, and recalibration of the instrument after each insertion or removal of a FAIMS stage, at a substantial cost in time and resources. Ions still pass FAIMS with the asymmetric waveform and CV switched off, but the transmission is poor because of large losses due to diffusion and Coulomb repulsion in a narrow analytical gap. Such losses decrease the sensitivity of instrument platforms without FAIMS, typically to unacceptable levels. Accordingly, there is a need for capability to switch off the FAIMS separation in hybrid platforms without significantly diminishing the instrument sensitivity.
[0006] In flow-driven FAIMS, all species traverse the gap in the same time defined by the flow speed and gap length. As the low-field (isotropic) diffusion coefficient of an ion D 0 is proportional to mobility K by the Einstein law, species with higher K values diffuse faster and thus spread farther in equal time. Second, more mobile ions further experience stronger field heating that increases the diffusion coefficient, and especially its longitudinal component D II (along the separation field) that determines ion loss on electrodes, above D 0 . Third, as the amplitude of ion oscillation in the V(t) cycle also scales with K, more mobile species undergo wider oscillations that effectively constrain the gap. These three factors add to a pronounced discrimination against more mobile ions, which are preferentially lost in a gap of any geometry. This is unrelated to the discrimination based on the K(E) form that occurs in curved gaps only (A. A. Shvartsburg, R. D. Smith. J. Am. Soc. Mass Spectrom. 2007, 9, 1672). This effect distorts the FAIMS spectra, complicating quantification, affecting the measured isomer abundances, and reducing the sensitivity and reliable dynamic range. Same effect decreases the FAIMS resolution for less mobile species, resulting in a non-uniform and sub-optimum resolving power over a spectrum. For a complex sample that comprises ions with a wide range of K, the discrimination may be severe enough to suppress more mobile species below the detection limit, precluding their observation in FAIMS, and prevent the resolution of different less mobile species that could otherwise be separated. As FAIMS is applied to increasingly complex proteomic and other biological samples that include more diverse species, the issue of mobility discrimination becomes more topical.
[0007] In field-driven FAIMS, the ion residence time in the gap (t res ) scales as 1/K and more mobile ions exit the gap faster. This offsets the proportionality of D 0 to K such that all ions would experience identical diffusional broadening at the FAIMS exit (assuming isotropic diffusion), but not the other two factors that contribute to the mobility-based discrimination in flow-driven FAIMS as described above. Therefore, the transition from flow- to field-driven FAIMS should ameliorate, but not eliminate, the generally unwanted suppression of ions with higher K values (A. A. Shvartsburg, R. D. Smith. J. Am. Soc. Mass Spectrom. 2007, 9, 1672). The remaining discrimination, still significant in simulations, will be adverse to many applications. Accordingly, one would desire a FAIMS system that reduces this discrimination further.
SUMMARY OF THE INVENTION
[0008] The invention is a system for separation, identification, and/or detection of gas-phase ions that includes, as the only or one of the analytical stages, field asymmetric waveform ion mobility spectrometry (FAIMS). The key novelty is that ions are moved through the FAIMS gap using the flow and field drive combined (i) consecutively or (ii) simultaneously to achieve non-obvious benefits not provided by either drive alone. With (ii), the field and flow may pull ions in the same or opposite directions.
[0009] One goal of the invention is providing a method for effective, rapid, and convenient switch-off of the FAIMS separation in hybrid platforms, to enable more sensitive analyses using the other stage(s) by limiting ion losses in the FAIMS gap. This is achieved by accelerating ion transit through the gap in the “off” mode compared to the “on” mode, where a minimum t res is determined by the desired resolution (A. A. Shvartsburg, R. D. Smith. J. Am. Soc. Mass Spectrom. 2007, 9, 1672). The acceleration is obtained by applying electric field E L along the gap in the “off” mode with V(t) and CV absent, alone or in addition to the flow moving ions in the same direction as the field. The direction of flow (if any) coincides with E L for cations and is opposite for anions. The field may be constant, such as used in DTIMS and described in the art for field-driven FAIMS, or time-dependent, e.g., a “traveling wave” similar to that used in traveling-wave IMS (TWIMS) to disperse ions by the absolute mobility (A. A. Shvartsburg, R. D. Smith. Anal. Chem. 2008, 80, 9689).
[0010] Instrument stages, if any, coupled to FAIMS include, but are not limited to, e.g., mass spectrometry (MS) in implementations such as quadrupole, ion trap, Fourier transform ion cyclotron resonance (FTICR), orbitrap, or time-of-flight; ion mobility spectrometry (IMS) based on the absolute K values in DTIMS, TWIMS, differential mobility analyzers (DMA), or other implementations; spectroscopies such as photoelectron, photodissociation, X-ray, or other spectroscopies; surface analysis or ion deposition stages, and combinations of these and other stages. These stages are usually subsequent to the FAIMS step, but may equally precede it within the scope of the invention.
[0011] In one embodiment, the stage subsequent to FAIMS is MS (or conventional IMS at sub-ambient gas pressure followed by MS), with FAIMS configured for FAIMS/MS or MS-only operation (or for FAIMS/IMS/MS or IMS/MS operation, respectively). Here, FAIMS may work at ambient or sub-ambient pressure. In the latter case, the FAIMS stage may be located inside the MS (or IMS) system enclosure, i.e., behind the MS (or IMS) inlet such as a heated capillary or curtain plate/orifice interface. The sub-ambient pressure preferably ranges from ˜0.1 to 1 atm, but may be lower to ˜0.01 atm, depending on the requirements for FAIMS resolving power and scan speed.
[0012] FAIMS stages known in the art commonly have planar or transverse (“side-to-side”) cylindrical geometry (U.S. Pat. No. 7,223,967). These and some other designs such as “hooked” (U.S. Pat. No. 7,491,930) permit free lateral spread of ions due to diffusion and/or Coulomb repulsion, thus the ion beams approaching the exit are ribbon-like with a rectangular cross-section. With any pressure in FAIMS, the transmission of ions from the exit of such units to subsequent stages at lower pressure is maximized by using (at the conductance limit) a slit-shaped aperture with the cross-sectional shape matching that of the beam as closely as possible (U.S. Pat. No. 7,339,166). Such slit interfaces can be employed to couple the FAIMS units to subsequent lower-pressure stages such as MS or conventional IMS (R. Mabrouki, R. T. Kelly, D. C. Prior, A. A. Shvartsburg, K. Tang, R. D. Smith. J. Am. Soc. Mass Spectrom. 2009, 20, 1768). Ribbon-shaped ion beams coming from slit apertures may be re-focused to circular cross sections using one or more electrodynamic ion funnels (U.S. Pat. No. 6,107,628). If the pressure in FAIMS is low enough for effective funnel operation, those beams may be focused by a funnel directly, with no conductance limit between the FAIMS unit and the funnel.
[0013] Another goal of the invention is to control the mobility-based discrimination in FAIMS, which is inevitable with either the flow drive or (to a lesser extent) field drive alone. The discrimination in planar gaps for ions of interest is minimized by applying a flow of specific speed to push ions in the direction opposing their drift in the longitudinal field E L , though the field prevails and ions traverse the gap under its control. Here, the field and flow directions are opposite for cations and coincide for anions, and the optimum flow velocity depends on E L and the mobility of ions of interest. Common ion sources such as electrospray ionization (ESI) and matrix-assisted laser desorption ionization (MALDI) produce intense background ions, which impede the analysis of target ions and thus are best removed as early as possible. Interfering ions are mostly solvent or matrix clusters that are often smaller and thus more mobile than the target analytes. Thus the mobility-based discrimination in FAIMS may suppress the chemical noise and is beneficial in some scenarios. Then the discrimination in planar gaps may be maximized by again applying flow and field E L that seek to move ions in opposite directions, but now with the flow prevailing and carrying ions of interest through the gap.
[0014] In summary, the invention combines the longitudinal electric field (drive) and gas flow (drive) in FAIMS to achieve analytical benefits impossible with either drive alone. In particular, consecutive application of the flow and field drives allows a FAIMS/MS instrument to toggle between the FAIMS/MS and MS-only mode without mechanical modifications. With FAIMS on, the field drive is disabled and ions are moved through the gap by flow only. With FAIMS off, the asymmetric waveform and compensation voltage are removed and the field drive is on. The combination of field and flow rapidly moves ions through the gap, minimizing their loss to electrodes. Then FAIMS can be easily switched on and off on the software level, with no hardware changes. Further, propelling ions through FAIMS using the field and flow drives together allows one to control and minimize mobility-based discrimination of ions in units of any geometry.
[0015] The purpose of the foregoing abstract is to enable the United States Patent and Trademark Office and the public, especially the scientists, engineers, and practitioners in the art not familiar with the patent or legal phraseology, to quickly grasp the essence of the technical disclosure of the application. The abstract is intended neither to define the instant invention that is measured by the claims, nor to limit its scope in any way.
[0016] Various advantages and novel features of the present invention are described herein and will become readily apparent to those skilled in the art from the following detailed description. In the preceding and following descriptions, the various embodiments, including the preferred embodiments and the best mode contemplated for carrying out the invention, have been shown and described. As will be realized, those embodiments may be modified in various respects without departing from the invention. Accordingly, the drawings and description of the preferred embodiments set forth hereafter are to be regarded as illustrative, rather than restrictive, in nature. Embodiments of the invention are described below with reference to the following accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIGS. 1 a - 1 b (Prior Art) show FAIMS stages that propel ions through the gap using a gas flow ( 1 a ) or an electric field ( 1 b ).
[0018] FIGS. 2 a - 2 b show a FAIMS stage that combines field and flow drives, according to an embodiment of the invention.
[0019] FIGS. 3 a - 3 b show a FAIMS stage coupled to a subsequent instrument stage, according to an embodiment of the invention.
[0020] FIGS. 4 a - 4 b show an integrated FAIMS/MS system, according to another embodiment of the invention.
[0021] FIGS. 5 a - 5 b show an integrated FAIMS/MS system, according to yet another embodiment of the invention.
[0022] FIG. 6 shows a peak profile simulated for a singly-charged ion.
[0023] FIG. 7 shows a calculated transmission efficiency through a FAIMS stage in the “off” mode for ions over a range of mobility, as a function of ion drift velocity due to longitudinal field relative to the flow speed.
DETAILED DESCRIPTION
[0024] The invention solves the problems with flow-driven FAIMS stages known in the art, where major losses of ions during their transmission through the analytical gap: (i) prevent effective use of other instrument stages in hybrid instruments without FAIMS filtering, and (ii) cause significant mobility-based discrimination. In particular, the invention enables operating various platforms comprising FAIMS, such as FAIMS/MS, FAIMS/DTIMS, FAIMS/TWIMS, FAIMS/DTIMS/MS, and FAIMS/TWIMS/MS, with FAIMS “on” or “off”. This allows for maximizing the specificity and reducing chemical background (with FAIMS on) and maximizing the sensitivity, throughput, and quantification accuracy without the distortions introduced by FAIMS (with FAIMS off). In another aspect, the invention controls and minimizes mobility-based discrimination of ions in FAIMS.
Asymmetric Waveforms
[0025] The waveform profiles for FAIMS include rectangular, bisinusoidal, clipped-sinusoidal, and their derivatives and superpositions (A. A. Shvartsburg, Differential Ion Mobility Spectrometry , CRC Press, Boca Raton, Fla., 2008), which reference is incorporated herein in its entirety. In one embodiment, the invention employs an exemplary bisinusoidal V(t), e.g., with a frequency of w=750 kHz. The waveform is produced using a power supply that includes a resonating LC circuit adding, e.g., 750 and 1500 kHz harmonics (at a 2:1 amplitude ratio), as is known in the art. As in other contexts, the present invention would optimally employ a rectangular waveform with appropriate “high-to-low” ratio (A. A. Shvartsburg, R. D. Smith. J. Am. Soc. Mass Spectrom. 2008, 19, 1286), but harmonic-based waveforms may be preferred for instrumental reasons.
[0026] FIGS. 2 a and 2 b illustrate exemplary FAIMS stages 100 . These stages include two planar electrodes 20 composed of segments 10 , each electrically insulated from the others so that distinct voltages can be applied to each segment to create a longitudinal field (E L ) 30 along the analytical gap 12 . An ionization source 2 (e.g., ESI) produces ions 3 that enter gap 12 and are moved through the gap by gas flow drive 4 , field drive 30 , or both. The term “field drive” means an electric field (constant or time-dependent) that moves ions along gap 12 at a selected velocity. The term “flow drive” means a flow of gas at a certain rate that propels ions through gap 12 at a selected velocity. Movement of ions solely by flow drive 4 or field drive 30 is termed “flow-driven” or “field-driven”, respectively. In various embodiments, ions are moved through the gap by a combination of flow 4 and field 30 . The two drives can pull ions in the same direction ( FIG. 2 a ) or in opposite directions with the flow slowing the ion drift along the gap, i.e., in a counter-flow regime ( FIG. 2 b ). A fixed longitudinal field 30 may be provided by inserting resistors between all adjacent segments 10 and applying a constant voltage between the first and last segment. The field 30 may also be established by directly addressing some or all segments, which would permit a time-dependent field (e.g., a traveling wave). In an alternative embodiment without segmentation, the FAIMS electrodes 20 or their surface parts facing the gap are made of a resistive material. Field 30 is then created by applying a constant voltage between the electrode termini. All such modifications as will be envisioned by those of ordinary skill in the art in view of the disclosure are within the scope of the invention. No limitations are intended.
[0027] The disclosure is not limited to the regime where a field moves ions against counter-flow ( FIG. 2 b ). Instead, a forward flow may carry ions through the gap against a retarding potential gradient seeking to pull them back. Such a forward flow mode may be useful to improve FAIMS resolution by extending the ion residence in the gap. Further, t res would now increase for more mobile ions, augmenting the discrimination against them beyond that with the flow drive only. The species with K values above some cutoff, will be swept back and not pass the gap, amounting to an infinite discrimination. As discussed above, suppression of more mobile (typically small) ions would benefit some applications.
[0028] FIGS. 3 a and 3 b show a FAIMS unit 100 of the invention at ambient pressure, coupled to another instrument stage 40 . In the “on” mode ( FIG. 3 a ), the electrodes 20 carry V(t) 18 and CV 8 . The longitudinal field 30 along the gap 12 is switched off by applying equal voltages to all segments 10 , and only the gas 4 carries ions through the gap. In the “off” mode ( FIG. 3 b ), both V(t) 18 and CV 8 are off. The longitudinal field 30 is switched on to move ions in the same direction as the flow 4 . Pulled by both electric field 30 and gas 4 , ions traverse the stage 100 substantially faster (e.g., by 10 times compared to “on” mode) to minimize ion losses in the gap 12 . While FIGS. 3 a and 3 b show the FAIMS unit 100 preceding the stage 40 in ion progression through the system, the invention encompasses any order of FAIMS relative to other stage(s), including that subsequent to all of them or preceding some and subsequent to others.
[0029] FIGS. 4 a and 4 b show a FAIMS/MS (or FAIMS/IMS/MS with sub-ambient pressure IMS) system 200 , according to another embodiment, that incorporates a FAIMS stage 100 as an integral component of MS (or IMS/MS) platform 40 , effecting separation, characterization, or detection of gas-phase ions. System 200 retains optimum instrument sensitivity, and FAIMS can be switched on ( FIG. 4 a ) for FAIMS/MS (or FAIMS/IMS/MS) analyses or off ( FIG. 4 b ) for MS-only (or IMS/MS) analyses without removing stage 100 . Here, stage 100 is at sub-ambient pressure, behind the inlet capillary 5 within the first vacuum region 24 of MS (or IMS/MS) platform 40 . For optimum ion transmission, the aperture 37 providing the conductance limit from FAIMS stage 100 to the following stage 26 at a lower pressure may be slit-shaped, depending on the FAIMS unit geometry. In other aspects, the FAIMS operation in “on” and “off” modes copies that at the ambient pressure, described with reference to FIGS. 3 a and 3 b using the same nomenclature.
[0030] FIGS. 5 a and 5 b show still yet other embodiment for an integrated FAIMS/MS (or FAIMS/IMS/MS with sub-ambient pressure IMS) system 200 . Here, FAIMS stage 100 is interfaced to the following vacuum stage 26 using an electrodynamic ion funnel 35 , though a slit or aperture of another shape may still be placed after the FAIMS exit (as in FIG. 4 a ) prior to the funnel, depending on the pressure in the FAIMS and funnel regions. In other aspects, the FAIMS operation in “on” and “off” modes is as described previously with reference to FIGS. 4 a and 4 b using the same nomenclature.
[0031] In its first aspect, the invention hinges on the realization that switching the FAIMS stage “off” in hybrid platforms by simply accelerating the flow is less effective and convenient than the present solution. With the flow drive only, the residence time t res is proportional to the inverse flow speed. As high ion transmission through the gap requires a major reduction of t res compared to that necessary for effective FAIMS separation, switching FAIMS “off” without unacceptable ion losses would involve drastic flow acceleration. This would cause severe losses at the interface of FAIMS to subsequent lower-pressure stages such as MS or sub-ambient pressure IMS (because of the mismatch between the increased outflow from FAIMS and limited gas conductance to those stages), unless the conductance and the pumping capacity of these stages are raised to the higher FAIMS flow level. However, such increase of the pumping capacity is generally impractical, and the higher inlet conductance would not match the reduced outflow from FAIMS switched “on”, causing other problems. Further, the electrode voltages and thus field E L can be manipulated faster than the flow by orders of magnitude, allowing far more rapid and flexible toggling between the “on” and “off” modes. In the second aspect of the invention, controlling and reducing the mobility-based discrimination requires a combination of field and flow drives. Switching FAIMS on/off or adjusting the mobility-based discrimination may be enabled in the instrument control software. In particular, the invention allows rapid manual or automatic toggling between the “on” and “off” modes. Such toggling may be carried out in a data-dependent manner, depending on the measured signal intensity (e.g., with FAIMS switched “off” if the signal overall or in a particular m/z region in MS falls below a pre-set threshold) or spectral properties (e.g., with FAIMS switched “on” if the spectral complexity exceeds a certain level).
Longitudinal Field Intensity for Effective “FAIMS-Off” Operation
[0032] The magnitude of E L for effective ion transmission with FAIMS “off” can be estimated from the required reduction of t res compared to the “on” mode. For optimum resolution/sensitivity balance, planar FAIMS can transmit ˜10-20% of ions (at peak CV). Then, a near-100% transmission would require reducing t res by an order of magnitude, e.g.: (i) from ˜150 to ˜15 ms in a “full-size” FAIMS device with a ˜2 mm wide gap (A. A. Shvartsburg, F. Li, K. Tang, R. D. Smith. Anal. Chem. 2006, 78, 3706), or (ii) from ˜3 ms to ˜0.3 ms in a miniaturized device with ˜0.5 mm gap (R. A. Miller, G. A. Eiceman, E. G. Nazarov, A. T. King. Sens. Actuat. B 2000, 67, 300). This means increasing the longitudinal ion velocity by the same factor of 10, i.e., (i) from ˜0.33 m/s (˜5 cm gap length traversed in ˜150 ms) to ˜3.3 m/s, or (ii) from ˜5 m/s (˜1.5 cm gap length traversed in ˜3 ms) to ˜50 m/s. With an unchanged gas flow, the drift ion velocity (in the longitudinal field) should be 9× flow velocity, i.e., 3 m/s in (i) or 45 m/s in (ii). Typical ions of interest generated by ESI sources 2 have K ˜1-2 cm 2 /(Vs) in N 2 or air at ambient temperature and pressure. Thus, achieving the above drift velocities requires an E L of ˜150-300 V/cm in (i) and ˜2.2-4.5 kV/cm in (ii). A somewhat higher or lower E L may be optimum when looking at species with K<1 or >2 cm 2 /(Vs), respectively. In any event, the needed E L values are well within the range of dispersion fields normally created by waveform 18 (˜20-30 kV/cm) and thus can be established without interfering with FAIMS separation across the gap 12 , or field heating of ions significantly beyond that at the V(t) peak (A. A. Shvartsburg, F. Li, K. Tang, R. D. Smith, Anal. Chem. 2007, 79, 1523). From the engineering perspective, in (i), setting the maximum E L =300 V/cm over a 5-cm long gap 12 requires a voltage drop of 1.5 kV, which is reasonable given the typical DV ˜4-5 kV. If the longitudinal field 30 is created using segmented electrodes and the segments are 1-mm long (the maximum reasonable for 2 mm gap width), the voltage ladder steps would be ˜30 V, or well under the breakdown threshold of ˜200 V for any distance in ambient air or N 2 (J. M. Meek, J. D. Craggs. Electrical Breakdown of Gases . Wiley, NY, 1978).
[0033] FIGS. 6 and 7 present simulation results for an exemplary “on/off FAIMS” stage of the invention, featuring planar electrodes 10 , a gap 12 of 2 mm width, a bisinusoidal V(t) with w=750 kHz and DV=4 kV, a flow drive 4 (in the “on” mode), and t res =100 ms. FIG. 6 shows the peak profile for a (1+) ion with K=2 cm 2 /(Vs) in N 2 gas, with the coefficient (α 2 ) in the K(E) expansion equal to 0.86E-10 (cm/V) 2 . FIG. 7 shows the transmission efficiency for exemplary ions with K=1, 2, and 3 cm 2 /(Vs) through the gap with FAIMS “off”, as a function of the ratio of the ion drift velocity (due to longitudinal field 30 ) to the speed of flow 4 . These results demonstrate that accelerating the ion transit tenfold when FAIMS is off virtually eliminates ion losses, even for the most mobile species with fastest diffusion. A more modest acceleration by ˜5 times still produces >90% transmission in all cases while halving the needed E L , perhaps a reasonable compromise between the transmission efficiency and expense of establishing the longitudinal field.
Controlling and Minimizing Mobility-Based Discrimination
[0034] Flow-driven FAIMS discriminates against ions of higher mobility for the three reasons stated in the introduction. This is especially consequential in global analyses, where the K values of actual or potentially present species may differ by up to ˜5 times (A. A. Shvartsburg, R. D. Smith. J. Am. Soc. Mass Spectrom. 2007, 9, 1672). As described herein, the field drive removes only the first factor contributing to the effect, and high-K ions are still discriminated against. The present invention teaches reducing the remaining discrimination by applying a counter-flow 4 that retards the ion drift through FAIMS caused by field 30 . Such counter-flow increases t res for all ions, but more so for less mobile ions t res that drift slower. For example, in a 7-cm long gap 12 , achieving 100 ms and thus a longitudinal velocity of 70 cm/s for a species A with K=3 cm 2 /(Vs) calls for E L =23 V/cm. At the same E L , another species B with K=0.9 cm 2 /(Vs) drifts with a velocity of only 21 cm/s. A counter-flow 4 with linear speed of 5 cm/s will diminish the net transit velocity and thus raise t res by 8% for A but 31% for B. The effect of counter-flow obviously increases at higher flow speeds. With common operating parameters (e.g., a 2 mm gap and bisinusoidal waveform with w=750 kHz), eliminating the residual discrimination in field-driven FAIMS between A and B requires increasing t res for the latter by ˜50% relative to the former. In the above scenario, this would happen at the flow speed of 8 cm/s, with the net transit velocity reduced by 12% (i.e., to 62 cm/s) for A, but by 62% (i.e., to 13 V/cm) for B. A counter-flow limits analyses to ions with K exceeding some threshold that corresponds to the zero net transit velocity: less mobile species are swept back through the gap and not observed. At the above flow speed of 8 cm/s, that threshold is K ˜0.3 cm 2 /(Vs). In practice, nearly all species generated by ESI have greater K values, and the lower K limit is not a major analytical impediment. Thus, no limitations are intended.
[0035] Besides the advantage of counter-flow for reducing the mobility-based discrimination in FAIMS, it may also provide a substantial benefit of sweeping the neutral species (e.g., arising from the ESI solvent vapor) out of the analytical gap and preventing them from entering subsequent stages such as MS. As is known in the art of DTIMS, removal of neutral contaminants from the IMS volume suppresses the ion-molecule clustering and charge exchange between ions and neutrals. These precautions often improve sensitivity by preventing the loss of analyte ions to those reactions and preclude the emergence of artifact features reflecting the products.
[0036] While a number of embodiments of the present invention have been shown and described, it will be apparent to those skilled in the art that many changes and modifications may be made without departing from the invention in its broader aspects. The appended claims are therefore intended to cover all such changes and modifications as fall within the true spirit and scope of the invention. | A differential ion mobility spectrometry or field asymmetric waveform ion mobility spectrometry (FAIMS) platform is disclosed that utilizes both gas flow and electric field, consecutively or simultaneously, to move ions through the analytical gap. The consecutive combination of flow and field enables rapid and flexible switching of the FAIMS stage “on” (for ion separation) and “off” (for high non-selective transmission) with no hardware modifications. This capability is needed for effective use of multidimensional instrument systems that couple FAIMS to mass spectrometry and/or conventional ion mobility spectrometry. The joint application of flow and field allows controlling the discrimination against high-mobility ions, maximizing it to remove the chemical noise or minimizing it to make the analyses of complex samples more predictable and uniform. | 6 |
BACKGROUND
[0001] 1. Field
[0002] The embodiments relate to a method, micro electromechanical device and system using a lift off process, and more particularly to using the lift off process to form metal free standing membranes of a predetermined desired thickness.
[0003] 2. Description of the Related Art
[0004] Multilayered ultra-thin metallic membranes with area of several millimeters and fixed thickness of less then hundred nanometers are applied currently as essential device components for transition radiation laser optics. Although, techniques for one layered free-standing micromachined membranes fabrication on silicon wafer exist, the fabrication of freestanding multilayered structures suffers from complex processing issues. With the traditional micromachining build up technique, when the stack of membranes is created and then the diaphragms supported material is removed, the major issue is qualitative release of the sacrificial supported material. Wet etch or dilution are rather lengthy processes and usually cause fatal membranes sticking, while dry etch damages the material of membrane due to sputtering.
[0005] FIG. 1 illustrates a typical silicon build up technique with membranes attached to the pillars after sacrificial layer release.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The embodiments are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:
[0007] FIG. 1 is a cross sectional view of a traditional micromachined membrane;
[0008] FIG. 2 is a perspective view of a protective layer added to a wafer according to an embodiment;
[0009] FIG. 3 is a cross sectional view showing the resist profile of the wafer of FIG. 2 according to an embodiment;
[0010] FIG. 4 is a perspective view showing the wafer in the combination of FIG. 3 as having been electroplated according to an embodiment;
[0011] FIG. 5 is a cross sectional top plan view showing the embodiment of FIG. 4 before top protective layer deposition according to an embodiment;
[0012] FIG. 6 is a perspective view showing the combination of FIG. 4 showing a peel-off process according to an embodiment;
[0013] FIG. 7 is a perspective view showing the electroplated membrane after a peel-off process according to an embodiment;
[0014] FIG. 8 is a top plan view of a multiple formed film from a peel-off process according to an embodiment;
[0015] FIG. 9 is a is a perspective view of diced films stacked according to an embodiment;
[0016] FIG. 10 illustrates the stack of FIG. 9 inserted into a mechanical device for alignment.
DETAILED DESCRIPTION
[0017] The embodiments discussed herein generally relate to a method and micro electromechanical device for non-limited stack of ultra-thin metallic membranes with fixed distances between membranes. Referring to the figures, exemplary embodiments will now be described. The exemplary embodiments are provided to illustrate the embodiments and should not be construed as limiting the scope of the embodiments.
[0018] Various operations will be described as multiple discrete operations, in turn, in a manner that is most helpful in understanding the present invention, however, the order of description should not be construed as to imply that these operations are necessarily order dependent. In particular, these operations need not be performed in the order of presentation.
[0019] FIG. 2 illustrates a beginning of a process for providing an electro-mechanical device where a protective layer added to an oxidized silicon wafer. The nature of the silicon oxide does not significantly influence the properties of the final electromechanical device (i.e., the same properties were found in case of low pressure chemical vapor deposited (LPCVD) and plasma enhanced chemically vapor deposited (PECVD) oxides). In one embodiment the protective layer is an alkaline protective polymer, such as Protek™. In one embodiment the alkaline protective polymer is spun on the oxidized surface of the silicon wafer to get the thickness of about 8 nm and then cured up to final hardening.
[0020] Next the membrane of the required metal with a desired (i.e., the metal membrane has a predetermined thickness) thickness is sputtered onto the cured protective layer. The metal of the diaphragm itself is protected with patterned resist using a “lift off.” This is essential for further sputtering of the seed layer for electroplating. The profile of the patterned resist is shown in FIG. 3 .
[0021] Following a seed layer for electroplating is sputtered on to prepare for a “peel off” treatment surface. In one embodiment, the seed layer is single layer of Au. In one embodiment, the thickness of the tri-layer ranges from 15 nm to 100 nm for optical devices. In another embodiment, the thickness of the tri-layer can exceed 100 nm. Next the patterned resist, which was used for membrane protection, is removed by solvent together with the sputtered on its surface seed layer. In one embodiment, the solvent used is acetone. In another embodiment the commercially produced solvent PRS3000 from Baker Scientific is used.
[0022] As illustrated in FIG. 4 , a thick mold resist is patterned with the same or similar reticle as for the “peel off” process to protect the membrane during electroplating. The metal, aimed to determine the distance between membranes, is electroplated on top of the seed layer, while the membrane itself remains protected with mold resist. That is, the metal layer determines a distance between each wafer in the soon to be stacked plurality of films. In one embodiment, the electroplated metal is Au (i.e., gold). In another embodiment, other metals can be used, such as Pt, Ni, etc. In yet another embodiment, a polymer material can be used. FIG. 5 illustrates a partially manufactured sputtered on metal tri-layer MoN/Mo/MoN membrane under electroplated Au (e.g., 6.9 μm thickness) with a sputtered gold seed layer (e.g., 350 Å thick).
[0023] The top surface of the wafer is protected with a second layer of the spun alkaline protective polymer before the wafer is diced into a plurality of wafers. FIG. 6 illustrates the separation or “peel off” of the film from the silicon wafer. In one embodiment the silicon wafer is delaminated from the other layers by using KOH allowing the layers to be separated or peeled-off one another. The protective polymer layer is then cleaned in a solvent(s) to dissolve the protective polymer layer leaving the tri-layer and the electroplated metal as illustrated in the diced film in FIG. 7 . This treating of the wafers with liquid solvent(s) delaminates the second protective polymer layer from the wafer.
[0024] FIG. 8 illustrates a cleaned wafer ready for dicing. The dicing of the film creates single multi-layered dies. In one embodiment the dies are treated with 20% water KOH (potassium hydroxide) solution in the temperature range of 20-45° C. up to the full delamination of the first (i.e., bottom) protective polymer layer from the oxidized silicon surface. This temperature range is used as higher temperatures can cause the second (i.e., top) protective polymer layer delamination and damage the membrane surface.
[0025] Delaminated films are then cleaned with liquid solvents. In one embodiment acetone and isopropyl alcohol (IPA) are used. In another embodiment, alternative solutions are used. The films are then dried under room temperature as illustrated in FIG. 8 .
[0026] The prepared films are then stacked as illustrated in FIG. 9 . It should be noted that while FIG. 9 illustrates a stack of three films, any amount of films can be stacked as desired. The stacked films are then assembled in a stack inside a mechanical fixture as illustrated in FIG. 10 . The mechanical fixture is sized as desired for the amount of films desired to be stacked. The mechanical fixture ensures the stacked films are aligned properly. The tri-layer membrane spaces the stacked metal films from one another.
[0027] The above embodiments allow creation of a non-limited stack of ultra-thin freestanding metallic membranes (less than 100 nm) with a fixed distance between each membrane. The purity of the layers is controlled for each membrane by using optical and electron microscopes before assembling. The independent cleaning and drying of the layers prevent the membranes from sticking after their assembly in a single multilayered device. In one embodiment the micro-electromechanical (MEM) devices including the stacked films are used as a component for transition radiation laser optics. The fabrication of the stacked metal films reduces the traditional complex processing issues and qualitative release of the traditional sacrificial supported material. And, the problem of membranes sticking to one another is eliminated.
[0028] While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative of and not restrictive on the broad invention, and that this invention not be limited to the specific constructions and arrangements shown and described, since various other modifications may occur to those ordinarily skilled in the art.
[0029] Reference in the specification to “an embodiment,” “one embodiment,” “some embodiments,” or “other embodiments” means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least some embodiments, but not necessarily all embodiments. The various appearances “an embodiment,” “one embodiment,” or “some embodiments” are not necessarily all referring to the same embodiments. If the specification states a component, feature, structure, or characteristic “may”, “might”, or “could” be included, that particular component, feature, structure, or characteristic is not required to be included. If the specification or claim refers to “a” or “an” element, that does not mean there is only one of the element. If the specification or claims refer to “an additional” element, that does not preclude there being more than one of the additional element. | A micro electromechanical device includes a substrate having stacked films. Each of the films includes a first layer and a second layer. The second layer is metal of a predetermined thickness. The stacked films are formed by electroplating the second layer on the first layer and lifting off a third layer, a fourth layer and a fifth layer. | 1 |
This is a division of application Ser. No. 048,560 filed May 11, 1987, now abandoned and itself a division of Ser. No. 839,557 filed on Mar. 14, 1986.
BACKGROUND OF THE INVENTION
The present invention relates to an improved composite closure cap of the type used for sealing containers and particularly plastic containers. More particularly, the invention relates to a composite closure which is especially useful for sealing plastic containers which have been formed by molding or vacuum forming methods.
Many products, and particularly many food products, have been traditionally packaged in glass or metal containers which are relatively expensive as well as often being relatively heavy. More recently there has been a development of other types of containers and one such container comprises a relatively thin plastic container which is either molded or vacuum formed. These containers are characterized by extremely thin walls and light weight so that they present a number of different problems related to their sealing with closure caps. The closure cap and the related package finish of the invention are particularly useful on these thin wall plastic containers. The closures are not only characterized by their ability to provide an easily formed and effective seal, but also by their ease of manufacture and their ability to provide a vacuum indicator where the closures are used in vacuum sealing procedures.
The closure cap of this invention and the related container finish are particularly useful upon inexpensive food packaging such as baby food packaging where the products are distributed in millions of packages per day requiring a simply manufactured and easily filled and sealed package. In addition, the closure cap is useful for baby food products where the user has occasion to open and then re-seal the package.
It is characteristic in vacuum sealng these thin-walled plastic containers to use a lesser vacuum than has been traditionally used with the glass and other thicker walled containers and the closure cap of the invention provides an effective vacuum indication even with a relatively low vacuum.
Another advantage present in packages of the invention sealed with the improved closure cap is the ability of the sealed packages to provide vacuum indication during an exposure of the sealed package to pressure changes, including those experienced where packages are transported through or to high altitude locations.
Accordingly, an object of the present invention is to provide an improved closure cap and sealing finish for a plastic package.
Another object of the present invention is to provide a closure cap particularly adapted for sealing thin-walled plastic containers.
Another object of the present invention is to provide an improved gasket and method of manufacture for a closure cap.
Another object of the present invention is to provide an improved cooperating container finish and closure cap for being applied thereto, particularly for thin walled plastic containers.
Other and further objects of the present invention will become apparent upon an understanding of the illustrative embodiments about to be described, or will be indicated in the appended claims and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the invention has been chosen for purposes of illustration and description and is shown in the accompanying drawings, forming a part of the specification, wherein:
FIGS. 1 and 2 are perspective views of the closure cap and the container finish illustrated in the sealed and unsealed positions.
FIG. 3 is a perspective exploded view illustrating composite closure cap with its plastic outer ring and separate cover portions.
FIG. 4 is a top plan view of a closure cap in accordance with the invention.
FIG. 5 is a diagrammatic illustration of improved means for applying the closure gasket in accordance with the present invnetion.
FIG. 6 is an enlarged top plan view of a gasket as applied to sheet material in accordance with the method of the invention.
FIGS. 7 and 8 are vertical sectional views of one preferred embodiment of the closure cap and the package finish in the unsealed and sealed positions respectively.
FIGS. 9 and 10 are vertical sectional views of another embodiment of the closure cap and container finish illustrated in their unsealed and sealed positions respectively.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1 thru 4 illustrate a preferred embodiment of the composite closure cap with a preferred container finish in accordance with the present invention. The composite cap 1 comprises an outer molded plastic ring or fitment 2 which receives a disc-like cover 3. As will be more fully described below, the fitment 2 includes container engaging threads 4 (FIG. 7) and the cover 3 includes an annular sealing gasket encircling the outer edge and container engaging portion of the cover 3.
FIGS. 7 and 8 illustrate in detail the preferred shaping of one embodiment of the closure cap 1 and container finish 5 illustrated more generally in FIGS. 1 thru 4 and FIGS. 9 and 10 illustrate another embodiment.
The closure cap 1 of the invention and the container finish 5 will be described in connection with a thin-walled plastic container 6 formed by the well known vacuum forming processes wherein thin sheets of plastic are shaped by vacuum forces over suitable forming molds. This method of forming articles such as hollow containers is well adapted to provide a precisely shaped finish at the container rim for engaging the sealing closure. The preferred closures 1 and the preferred sealing finishes 5 are also useful on containers of the same general shape provided by other container forming methods such as a blow molding or other container forming process.
As illustrated in FIGS. 7 and 8, one preferred closure cap 1 in accordance with the present invention, comprises a plastic fitment 2 including a closure skirt 7 with container engaging threads 4 formed on the interior of the skirt 7 and with suitable gripping knurls 8 provided on the fitment outer surface. The plastic fitment 2 comprises an annular cover engaging portion 9 extending inwardly from the top of the skirt 7 a sufficient distance to cover the upwardly facing rim 10 of the container 6.
The cover 3 comprises a relatively flat outer ring-like gasket receiving portion 11 and a domed central portion comprising a vacuum indicating button 12 formed into the material of the cover 3.
A preferred method of providing a gasket on the disc-like cover 3 is illustrated in FIGS. 5 and 6. In accordance with this method, sheet material 13 of the appropriate thickness is passed through a rotary screen coating apparatus 14.
FIGS. 5 and 6 illustrate the method of forming the sealing gaskets using a rotary screen coating apparatus 14 which is applying gaskets 15 with the appropriate spacing on the sheets of tin plate 13 for subsequent blanking and forming operations to produce the individual closure cap covers 3. This apparatus includes the rotary screen 16 having ring-like apertures 17 cut in its surface for transferring the plastisol or other suitable gasket material to the sheet material. The plastic material is fed by a suitable pump from a plastic reservoir 19 and passes through an elongated feed nozzle 21 positioned within the rotary screen 16. A squeeze blade 22 positioned below the nozzle 21 forces the plastic material onto the surface of the sheet material 13. By this method the gaskets 15 are rapidly formed in the appropriate position on the sheet material 13 and the sheet material 13 is presented to the stamping and forming machines with the gaskets already in position.
A suitable thickness for a gasket is printed in accordance with this invention and is from 0.01 to 0.04 inches. The screens 16 are typically metal such as nickel. Differing screen mesh sizes are usefully employed and best results have been found to be obtained as far as gasket shapes and gasket thickness for 59 mesh screens although mesh openings per lineal inch may run between about 16 and 83.
For the printed gaskets 15 various plastisol compounds are useful, however, significantly improved results have been obtained with relatively high viscosity plastisols. For flowed-in gaskets as illustrated in FIGS. 9 and 10 the conventional plastisol gasket formulations are satisfactory.
The closure cap and finish illustrated generally in FIGS. 1 thru 4 may employ the gasket 15 of this type on the covers illustrated in detail in the sectional views of FIGS. 7 and 8. Thus, after the application of the gaskets 15 to the sheets 13, they are blanked and formed to the disc-like covers with the gaskets 15 at the outer edge of the cover and with a domed vacuum indicator 12 formed in the central portion of the cover 3 extending inwardly from a recessed shoulder. The flat edges on the covers 3 at the gaskets 15 are relatively flexible, as contrasted with covers 32 (FIG. 9), and this cover flexibility provides excellent abuse resistance as, for example, when the packages 6 are squeezed.
The vacuum button 12 is shaped to provide a sensitive vacuum indicating movement from a depressed position under vacuum to the normal raised position of the button as illustrated in FIG. 7. FIG. 8 illustrates the vacuum button 12 in its sealed position on a vacuum packed product.
In order to provide for a predictable and constant vacuum button 12 action independently of the sealing forces on the cover 3 edges, the preferred plastic ring 2 for the closure cap of FIG. 7 has a downwardly facing channel 23 formed in the cover portion 10 of the plastic ring 2 and positioned at the outer edge of the cover 3 in the sealed position illustrated in FIG. 8.
In order to facilitate the sealing of threaded closure caps such as the embodiment of the cap 1 illustrated in FIG. 7, it is desirable to permit at least a portion of the cap application to be performed with a press-on action to force the caps 1 directly downwardly onto the container threads and to thus limit the more complicated rotary sealing action to only a finally fractional turn of the closure cap 1 on the container 9. This sealing characteristic is provided in the closure cap of FIGS. 7 and 8 by forming steeply inclined surfaces 26 on the undersides of the container engaging threads 4 on the cap skirt 7. These surfaces which have an angle with the horizontal of 45° or more thus pass easily over the container threads 27. To further facilitate this action, the upper surfaces 28 of the container threads 27 are similarly steeply slanted to have an angle and cross-section of 45° or greater with the horizontal. These skirt and thread shapes in combination with the slight compressability with the thin-walled plastic package readily provide the desired result of a full or partial press-on sealing capability. The upwardly facing surfaces 29 on the closure cap threads 4 and the downwardly facing surfaces 30 on the container threads 27 are provided with a less suitably inclined surface of about 30° or less to assure the retention of the seal after the closure cap 1 has been applied. While the cover 3 is conveniently formed of metal plate, it may also be formed with similar steps with composite sheets of suitable non-metallic materials.
The container 6 illustrated in FIGS. 7 and 8 has a suitable sealing rim formed to provide a top, and edge seal with the cover gasket 15 in the manner illustrated in FIG. 8 and with the desired amount of rigidity being provided at the container rim by the inwardly extending rim flange portion 10.
FIGS. 9 and 10 illustrate at 31 another embodiment of the closure cap where the cap cover 32 is formed with a gasket receiving channel 33 at its outer edge for receiving a flowed-in plastisol gasket 34 to form the package seal as illustrated in FIG. 10. This embodiment of the cap is illustrated with cap and container threads lacking the steeply slanted surfaces described in connection with threads of FIGS. 7 and 8, but may employ such threads if desired, as well as the pressure relief channels such as channel 23 described in connection with the closure cap of FIG. 7.
It will be seen that an improved closure cap and container finish have been described for use with volume produced packaging for products such as baby foods and others. The closure is particularly useful for high speed sealing for providing high use sealed packages and for permitting sealed containers to be opened and reclosed. A composite closure cap in accordance with the invention, as described above, is particularly useful on thin-walled plastic containers such as are formed by vacuum forming processes.
As various changes may be made in the form, construction and arrangement of the invention and without departing from the spirit and scope of the invention, and without sacrificing any of its advantages, it is to be understood that all matter herein is to be interpreted as illustrative and not in a limiting sense. | A closure cap is disclosed for sealing containers and particularly for sealing thin-walled vacuum formed containers with threaded rims. The closure cap is a composite closure having a molded plastic ring for engaging the container and for mounting a disc-like metal cover. The metal cover includes a vacuum indicating disc particularly adapted for providing a positive indication for relatively low vacuums and the closure cap is adapted for being sealed onto the container with a combination of press-on and screwing action to provide for high speed vacuum sealing. The vacuum indicating action of the vacuum button is improved by providing a channel in the plastic ring at the edge of the metal cover for stablizing the button operation at the desired low vacuum levels. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a bracket for mounting sheets of prefabricated plasterboard or drywall to the frame of a wall or partition during construction, modification, or rehabilitation of a building. The bracket is nailed or otherwise fastened to wall or partition studs in locations requiring but lacking nailing surfaces for fastening drywall sheets to the studs. Installation of several brackets thus provides a surface for supporting drywall fasteners which previously could not be employed for lack of a nailing surface or the like. Drywall is then fastened in place by screwing drywall screws through the drywall and into the bracket.
2. Description of the Prior Art
In construction or rehabilitation of a building, it is common practice to erect an open wooden frame, which frame is then finished by erection of a finishing surface. Prefabricated panels provide convenient and economical components for covering large wall areas with relatively minimal expense in time and material. In much residential and commercial construction today, plasterboard has gained favor as a desirable construction material for finishing interior walls and partitions.
Since framing occurs prior to finishing, the finishing trade is dependent upon framing carpenters to anticipate the needs of drywall installers. However, although framing carpenters are generally well aware of this dependency, for many reasons, framing is occasionally inadequate for installation of surface paneling. An inexperienced or hurried carpenter may fail to recognize or make the effort to provide sufficient wooden studs for nailing or screwing paneling to the wooden frame. Other trades may have modified a frame for their particular purpose, and failed to accommodate drywall installers. A homeowner performing his or her own work may lack necessary experience to recognize or anticipate the need for nailing surface. Regardless of the cause, drywall installers regularly are faced with the necessity of adding to available nailing surface.
A typical response by drywall installers to this need, in those instances when it arises in the course of construction, is to nail an auxiliary piece of lumber to the unfinished frame. However, this is not always easily performed. In many instances, the drywall installer lacks sufficient space to swing a hammer effectively, and the auxiliary lumber cannot be effectively fastened to the frame. Even where adequate auxiliary support members can be installed onto existing framing, this work may prove quite time consuming, difficult, and tiring.
The prior art has suggested many clips, brackets, and other hardware for enabling attachment to and joining of diverse construction elements. An L-shaped, perforated joining element is described in U.S. Pat. No. 3,127,961, issued to Bob G. Frazier on Apr. 7, 1964. This element lacks a reinforcing flange and tabs projecting from the two principal panels forming the ell, as are found in the present invention. Frazier's device also lacks a foraminous surface promoting penetration by a fastener, as provided in the instant invention.
U.S. Pat. No. 1,694,043, issued to Charles M. Thomson on Dec. 4, 1928, describes a wall attachment device which is in alternative embodiments L- or Z-shaped. This device lacks the reinforcing flange and preformed fastener apertures of the present invention. It also lacks a foraminous surface, different from that having preformed apertures, for promoting penetration of fasteners.
A generally L-shaped fastener is described in U.S. Pat. No. 2,490,018, issued to Homer C. Davis on Dec. 6, 1949. This device lacks the reinforcing flange and foraminous surface of the present invention. It also lacks the tab of the present invention, which, if added to Davis's device would prevent Davis's device from occupying a corner, as intended by Davis.
U.S. Pat. No. 3,741,068, issued to Julian Andruskiewicz on Jun. 26, 1973, describes a wallboard staple having a principal panel from which depend a second panel and two pointed piercing members. By contrast, the present invention has members projecting at an angle to the principal panel from both sides, rather than from just one side, as seen in the device of Andruskiewicz. Also, the device of Andruskiewicz lacks a foraminous surface for promoting penetration by fasteners.
A stud particularly intended for supporting plasterboard is shown in U.S. Pat. No. 1,609,541, issued to James C. Gooding on Dec. 7, 1926. However, the stud has generally complicated construction incorporating a metal shell providing at least three sides of a quadrilaterally bounded column. By contrast, the present invention has two perpendicular principal panels. Dimensionally minor projections from the two principal panels of the present invention are different from the three sided metal shell of Gooding.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.
SUMMARY OF THE INVENTION
The present invention provides a bracket which is intended to be nailed or screwed to a nailing surface of a framing member, and which has the effect of extending the framing member around a corner to a location suitable for fastening drywall paneling to a supporting surface, where that location has not been reached by framing. This is accomplished by nailing the bracket to an exposed or accessible nailing surface of the framing.
The bracket is configured generally L-shaped, having a base panel and a fastening panel which are perpendicularly disposed to one another. The fastening panel has apertures preformed therein, so that it may be readily nailed to the accessible surface of the framing. The base panel provides a support surface disposed perpendicularly to the nailing surface of the accessible framing member. A drywall panel is laid against and abuts the support surface, and is fastened thereto by drywall screws or the like which are driven into the base panel. The base panel has a dimpled or foraminous surface, for promoting penetration by drywall screws. In summary, the bracket is nailed to framing at an accessible surface of the framing while providing a supporting surface disposed perpendicularly to that employed to nail the bracket to the framing.
Two relatively minor members project from the bracket. The base panel is slightly bent along its outer edge to define a flange for opposing bending or deformation of the plane of the base panel. This flange is relatively unobtrusive, and plays a further role in mounting of the drywall panel in that it enables ready alignment of the bracket when manually placed against framing lumber. In addition to the flange, a tab projects from the bracket in a manner coplanar with the base panel.
When viewing the bracket from an end, the fastening panel forms the stem of a tee completed or topped by the coplanar base panel and tab. However, the tab is much shorter than the base panel, so that overhang of the top of the tee is not equal on both sides of the stem. The tab provides a stop enabling the bracket to be aligned with one surface of a framing member, thereby assuring correct location of the drywall panel.
The novel bracket is especially suited for modifying framing after completion of the framing phase of construction. It is easily nailed to framing in situations wherein nailing a relatively large and bulky piece of lumber is difficult or awkward. At the same time, the structure of the bracket is extremely compact, compared to lumber, while providing virtually equivalent support for mounting drywall.
The bracket is employed in plural short segments. Any appropriate number of brackets is employed to provide periodic fastening supports along an unsupported edge of a panel of drywall. Resultant ready modification of framing to accommodate mounting of drywall greatly expedites finishing work where framing is inadequate to give proper support for screwing drywall panels in place.
Accordingly, it is a principal object of the invention to provide a bracket for extending framing where framing is inadequate to give proper support for screwing drywall panels in place.
It is another object of the invention to enable nailing of a support for paneling to an accessible surface of framing while providing a support surface disposed perpendicularly to the nailing surface.
It is a further object of the invention to provide a stop enabling aligning of the bracket with a surface of a framing member.
Still another object of the invention is to provide preformed apertures for receiving nails, thereby expediting nailing of the bracket to framing.
An additional object of the invention is to render the base panel easily susceptible to penetration by drywall screws.
It is again an object of the invention to prevent bending or deformation of the plane of the surface of the member which supports drywall.
It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Various other objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:
FIG. 1 is a perspective view of the invention.
FIG. 2 is an environmental, side elevational view of the invention, shown partially broken away to reveal concealed detail.
FIG. 3 is an environmental perspective view of the invention, with the novel bracket shown partially in phantom for clarity.
FIG. 4 is an environmental, top plan view of the invention, with parts of the novel bracket and of environmental elements broken away to reveal concealed detail.
FIG. 5 is an environmental, perspective view of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to FIG. 1 of the drawings, novel paneling attachment bracket 100 is seen to comprise a flat base panel 102 and a flat fastening panel 104 arranged perpendicularly to and depending from base panel 102. Base panel 102 has a depth direction and dimension 106 and a width direction and dimension 108. Depth dimension 106 and width dimension 108 will be understood to be arbitrarily defined, for purposes of relating subsequently mentioned components. Base panel 102 provides the function ofengaging paneling (shown in subsequent figures) and for receiving fasteners(shown in subsequent figures) fastening the paneling to bracket 100.
Base panel 102 is characterized by having first and second lateral edges 110, 112 generally aligned with arrow 106 indicating the depth dimension of bracket 100, a joint 114 indicated in broken line, and a reinforcing flange 116 disposed generally parallel to width dimension 108 and projecting upwardly from base panel 102. Joint 114 is an arbitrary designation of a fold or bend line existing as an abstraction, and forms atransition between base panel 102 and fastening panel 104. Joint 114 is preferably disposed parallel to width dimension 108 and located on a lateral side of base panel 102 opposite that bearing flange 116.
Base panel 102 has two flat extensions 118 disposed in coplanar relation with base panel 102. Extensions 118 are connected to and extend from base panel 102 at joint 114. Preferably, two extensions 118 are provided, and are spaced apart from one another so that bracket 100 may be aligned with respect to square cut framing lumber, as will be described hereinafter. Ifformed by punching from fastening panel 104, then it will be apparent that formation of extensions 118 will leave voids 118A in fastening panel 104 which voids 118A correspond in configuration and complement their respective extensions 118. This construction does not impair overall strength of bracket 100, and serves to minimize weight of bracket 100 and to enable ready fabrication.
It is contemplated that bracket 100 will be formed by punching and bending from sheet metal stock, such as twenty-five gauge steel, although other materials may be selected. Sheet metal has requisite strength, and is thinand flat, for enabling drywall to be mounted without displaying unsightly bulges or offset due to material thickness of bracket 100. If sheet metal stock is selected for fabrication, then bracket 100 may be formed startingfrom a quadrilateral section of stock, and bent and punched to incorporate the features described herein.
Fastening panel 104 provides a member for fastening bracket 100 to a framing member, as will be shown hereinafter. Fastening panel 104 is joined to base panel 102 at joint 114 and depends from base panel 102, as contrasted with upturned flange 116, these relationships being shown in FIG. 1. Fastening panel 104 is disposed perpendicularly to base panel 102 for cooperation with square cut framing lumber, and is thus also perpendicular to extensions 118.
If fabricated from rectangular sheet stock, fastening panel 104 has a lateral edge 110 occupying a plane in common with lateral edge 110 of basepanel 102 and a lateral edge 112 occupying a plane in common with lateral edge 112 of base panel 102. A plurality of apertures 124 for receiving fasteners are formed in fastening panel 104. Preferably, three apertures 124 are provided, one being centered with respect to width dimension 108, or equidistantly from edges 110 and 122. The other apertures 124 are located, respectively, spaced apart from but in close proximity to edges 110 and 122.
Since bracket 100 is nailed to a visible and accessible framing member, apertures 124 may be preformed therein and arbitrarily located thereon. However, after installation of bracket 100 and placement of drywall paneling over bracket 100, bracket 100 is obscured. Precise location of a drywall screw is difficult at best, and would be time consuming even if possible. Therefore, preformed individual holes for receiving drywall fasteners are not provided. Instead, base panel 102 has a dimpled or foraminous surface providing many depressions 126 periodically located on the undersurface of panel 102, as seen in FIG. 1. Depressions 126 may, of course, comprise holes extending entirely through panel 102. As employed herein, provision of either dimples or perforations extending entirely through the material of base panel 102 will be referred to as foraminous.
Depressions 126 both reinforce base panel 102 and also tend to prevent the sharp point of a drywall screw from excessive wandering. These characteristics promote penetration of a drywall screw through base panel 102. Therefore, a drywall screw is readily driven into base panel 102 at any convenient location, and no obscured hole need be precisely located when fastening drywall paneling to bracket 100.
Having described construction of bracket 100, methods of use and advantagesof bracket 100 will now be set forth. Referring first to FIG. 2, bracket 100 has been secured to a framing header 10 by nails 12. Subsequently, drywall panel 14 is placed against base panel 102 of bracket 100 and secured in this location by drywall screw 16. Of course, several screws 16are driven into bracket 100, only one being visible in the view of FIG. 2.
After securement of drywall panel 14, a second drywall panel 18 is installed. In the situation depicted in FIG. 2, panel 18 is conventionallyinstalled, and is shown merely to illustrate cooperation with panel 14 and framing members 10, 20, and 22, which are typical of framing construction.In this typical construction, there are no other framing members near thoseshown. Therefore, there is no interference encountered by the exposed section of screw 16 or of reinforcing flange 116. It should be noted at this point that there would indeed be interference if flange 116 were bentto the same side of panel 102 as that from which fastening panel 104 depends.
The role of extensions 118 becomes clear in FIG. 2. Immediately prior to nailing to header 10, bracket 100 is moved into abutment with header 10. When fastening panel 104 contacts header 10, bracket 100 is forced downwardly until abutment of extensions 118 with header 10 ensues. At thispoint, bracket 100 is located so that face 14A of drywall panel 14 is flushwith face 10A of header 10. Bracket 100 thus provides the effect extending face 10A to the left of header 10.
Turning now to FIG. 3, a vertically oriented section of drywall panel 24 isshown secured to vertical stud 26 by bracket 100. Nails 28 for securing bracket 100 to stud 26 are shown in this embodiment, but may in other embodiments be more centrally located within fastening panel 104. In theseother embodiments, nails 28 could possibly be obscured by panel 24. Heads 30 of drywall nails are visible after being driven through panel 24 and bracket 100. Once again, bracket 100 has been placed in solid abutment with stud 26 by pressing fastening plate 104 and extensions 118 against two faces of stud 26.
FIG. 4 shows vertically oriented drywall panels 32 and 34 fastened to a stud 36 by two brackets 100. Drywall screws 38 and flanges 116 avoid interference with footer 40 by virtue of being located above footer 40, projecting instead into a void existing above footer 40 and to the right and left of stud 42. FIG. 4 shows that brackets 100 may be inverted, so that one configuration is usable on both right and left sides of stud 36.
FIG. 5 shows an installation employing a plurality of brackets 100, illustrating representative spacing thereof. Brackets 100 are preferably formed in one foot widths, which is a convenient width for building walls and partitions which are typically six to eight feet in height above a floor. Preferably, depth dimension 106 (see FIG. 1) and a corresponding depth dimension 128 (see FIG. 1) of fastening panel 104 are less than one and seven eighths inches, which dimension corresponds to an actual dimension of a nominal two inch dimension of commonly available framing lumber. Limitation of depth dimensions 106 and 128 assures that bracket 100 will not protrude beyond the various faces of a nominal two inch by four inch framing member. This framing member is the minimal size commonlyemployed in structural framing of buildings in the United States today. Of course, the preferred dimensions set forth above could be varied to accommodate other building standards or situations.
It will be apparent to one of ordinary skill in the art that construction and utilization of the invention may be modified and varied while retaining the original features and purpose. Obviously, bracket 100 is suitable for installing any type of paneling, not just of the drywall type, which paneling is fastened to a supporting surface by nailing, screwing, stapling, tacking, or by any other process employing a sharpenedfastener or even an adhesive.
As is apparent, the quadrilateral section need not be rectangular, as thereis little necessity that edges 110 and 112 be parallel to one another or normal to width dimension 108. The various edges, although shown and described as essentially linear, may be irregular or disposed at various angles not shown to one another. Further, materials and fabrication techniques need not be as described prior. Bracket 100 may be fabricated from other metals or materials, such as synthetic resin or fiberglass. Bracket 100 may be molded, or fabricated in still other ways.
It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. | A bracket for providing support for paneling which is customarily nailed or screwed to framing. The bracket comprises a base panel for receiving drywall screws and a support panel for nailing to framing. The base panel has a foraminous surface for promoting penetration by drywall screws and a reinforcing flange disposed at an angle to the base panel. The support panel is disposed perpendicularly to the base panel, and has preformed apertures for accepting nails to secure the bracket to framing. A tab is punched from the base panel and folded over so as to be coplanar with the base panel and perpendicular to the support panel. The bracket has a T-shaped configuration when viewed in end elevation. The support panel forms the stem of the T, and is topped on one side by the base panel and on the other side by the tab. | 4 |
BACKGROUND OF THE INVENTION
The invention relates to a sewing machine provided with a mechanism for producing various stitch patterns by operation of a pattern selecting dial, and more particularly relates to an additional device operated to change the ratio of forward and backward feeding of the fabric with operation of the same pattern selecting dial by utilizing a mechanism for producing stitch patterns including a needle control cam and a feed control cam controlling the feeding movement of the fabric in the forward and backward direction in a predetermined amount.
For stitching a fabric of great elasticity, it is required to feed the fabric in the forward and backward directions repeatedly, generally with the approximate ratio of feeding amounts to 2.5:0.5. Such type of stitches is generally called the "outline stitches". However, in the conventional sewing machines, a feed control cam is generally designed to provide the feeding ratio of amount 2:1 in the forward and backward directions to produce the normally stitched patterns.
SUMMARY OF THE INVENTION
It is, therefore, an object of the invention to produce suitable outline stitches of the feeding ratio approximately 2.5:0.5 in the forward and backward directions especially by utilizing the feed control cam normally used for producing the patterns of stitches.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a sewing machine mechanism incorporated with the invention,
FIG. 2 is a plan view showing a pattern selecting part of the sewing machine mechanism of the invention,
FIG. 3 is a front elevational view showing the pattern selecting part of the sewing machine mechanism,
FIG. 4 is a front elevational view showing a feed control part of the sewing machine mechanism positioned in one operation phase,
FIG. 5 is a front elevational view showing the feed control part positioned in another operation phase,
FIG. 6 is a front elevational view of a pattern indicating part of the sewing machine,
FIG. 7 is an exploded view of the sewing machine mechanism of the invention, and
FIGS. 8-11 are explanatory operational representations of the invention.
DETAILED DESCRIPTION OF THE INVENTION
In reference to FIGS. 1 and 2, main drive shaft 1 of the sewing machine is rotatably mounted on a machine housing 2. A worm 3 is mounted on a transverse shaft 4 secured to the machine housing 2. The worm 3 is in mesh with another worm (not shown) secured to the main drive shaft 1, and is designed to be rotated one revolution while the main drive shaft 1 rotates six revolutions. As shown, the worm is formed as a unit with a group of needle control cams 5 and a group of feed control cams 6.
A control shaft 7 is turnably mounted transversely of the machine housing 2, one end of which protrudes out of the machine housing to support thereon an operating dial 8 for selecting patterns to be stitched. As shown in FIG. 7, the dial can be turned and held at a desired position defined by notches 9a of a disc 9 secured to the machine housing 2, by way of a pin 10 biased by a spring 11 towards the disc 9 between the dial 8 and the disc 9 and selectively engaged in one of the notches 9a as the dial 8 is turned.
Additionally in reference to FIG. 7, a pattern selecting cam 12 and a feed selecting cam 13 are secured to the control shaft 7. The pattern selecting cam 12 is formed with radially offset cam lifts 12a and axially offset cam lifts 12b. The feed selecting cam 13 is formed with a spiral cam groove 13a on one side thereof. A sector member 14 is turnably mounted on a boss 12c of the pattern selecting cam 12 with a washer 15 installed therebetween. The sector member 14 is provided with a projection 50 on one side thereof and is formed with a cam face 14a on the other side thereof to be operated to regulate the lateral amplitude of the needle.
As shown in FIG. 4, a switching rod 27 has a pin 29 provided at one end thereof and engaged in the spiral cam groove 13a. In the region of the cam groove 13 within the first complete revolution of the pattern selecting dial 8, the radially outer cam groove 13b displaces the rod 27 to the leftward position. On the other hand, within the second revolution of the pattern selecting dial 8, the radially inner cam groove 13c displaces the rod 27 to the rightward position. The radially inner end part 13d of the spiral cam face 13a is located between the radially outer cam face 13b and the radially inner cam face 13c, and is used to produce the outline stitches, the object to be obtained by this application.
As shown in FIG. 1, a frame 16 is at the upper end thereof swingably mounted on the maching housing 2. A needle bar 18 is supported on the swingable frame 16 and is vertically reciprocated. A transmission rod 19 is at one end turnably connected to a pivot 20 at the upper end 17 of the swingable frame 16 and is at the other end formed with a follower 19a to selectively engage the group of pattern cams 5. An arm 21 is secured to the transmission member 19 and has a pin 22 provided on one end thereof to engage the cam lifts 12a, 12b of the pattern selecting cam 12 for selectively engaging the cam follower 19a to the group of needle control or pattern cams 5 as the dial 8 is rotated, since the follower 19a is normally biased towards the pattern cams 5. Another arm 23 is secured to the transmission member 19 and has a pin 24 provided at the lower end thereof to engage the cam face 14a of the sector member 14 operated with regulate the lateral amplitude of the needle bar 18.
A U-shape frame 25 is swingably mounted on the transverse support shaft 4 embracing the unit of worm 3, the groups of pattern cams 5 and feed control cams 6. A switching cam 26 is turnably mounted on the support shaft 4 within the U-shape frame 25. The switching cam 26 is formed with a releasing cam lift 26a and an arcuate extension providing a forward wall 26b and a rearward wall 26c connected to each other by a sloped face 26d and also providing a cam lift 26e. The aforementioned switching rod 27 is formed with an elongated opening 27a to allow the control shaft 7 to pass therethrough. A collar 28 is secured to the control shaft 7 to prevent the displacement of the switching rod 27 axially of the control shaft 7. The switching rod 27 has the other end connected to a pin 30 provided on one side of the switching cam 26.
A U-shape arm 31 is at the lower end thereof turnably mounted on a pin 32 provided at the free end of the arm 25a of the U-shape frame 25 and is prevented from the displacement axially of the pin 32 by a washer 33. A U-shape lever 34 is at the lower holes 34a thereof turnably mounted on the pin 32 of the U-shape frame 25. A pin 35 is transversely mounted on the upper holes 34b of the U-shape lever 34. The pin 35 is at one end protruded out of the U-shape lever on one side thereof to support thereon a roller 36. The U-shape lever 34 has a lower extension 34c provided with a pin 37 at the intermediate part thereof. As shown in FIGS. 4 and 5, a tension spring 38 is at one end hanged to the lower end of the U-shape lever 34 and is at the other end anchored to the U-shape frame 25, so as to normally press the pin 37 of the U-shape lever 34 against the outer peripheral edge of the arcuate extension of the switching cam 26 where the cam lift 26e is formed.
A follower 39 is at the lower end thereof mounted on the pin 32 of the U-shape frame 25 within the U-shape arm 31 and the U-shape lever 34. The follower 39 is at the upper end thereof held by a pin 40 transversely mounted on the U-shape arm 31 as shown in FIGS. 1 and 7. The follower 39 is provided with an upper projection 39a to selectively engage the feed control cams 6 as will be mentioned hereinafter, and is provided with a lower projection 39b. The follower 39 is at the lower projection 39b normally pressed against the forward wall 26b or the rearward wall 26c of the switching cam 26 by a spring 41. The U-shape arm 31 has an upper projection 31a which is engaged by the cam lift 26a of the switching cam 26, so that the U-shape arm 31 may be disengaged from the feed control cam 6a or 6b when another feed control cam is selected.
A feed transmission lever 42 is, at the opening 42a at one end part thereof, supported on the pin 32 of the U-shape frame 25, and is also, at the hole 42b provided on the right side of the opening 25, supported on one end of the transverse pin 40 protruded out of the U-shape arm 31 on the rear side thereof as shown. The feed transmission lever 42 has an arcuate slot 42c formed at one end thereof adjacent to the opening 42a. The arcuate slot 42c is, as shown in FIGS. 9 and 10, composed of a cam 42d substantially coaxial with the support pin 32 and an end cam 42e of a radius smaller than that of the cam 42d. The arcuate slot 42c is in engagement with the roller 36 provided on the side of the U-shape lever 34.
An operating dial 45 is secured to one end of a shaft 44 which is protruded out of the machine housing 2 and rotatably mounted on the machine housing 2. The dial 45 is selectively held at the angular positions thereof determined by the notches 46a formed around a disc 46 secured to the machine housing, since a pin 47 provided between the dial 45 and the disc 46 is normally pressed against the disc 46 by a spring 48, so that the pin 47 may be selectively inserted into the notches 46a as the dial 45 is rotated. An arm 43 is at the upper end secured to the inner end of the shaft 44. A transmission rod 49 is at one end connected to the lower end of the arm 43 and is at the other end connected to the pin 50 of the sector 14 by a washer 52. Thus the dial 45 is operated to determine the position of the follower 19a relative to the pattern cams 5 by way of the arm 23 having the pin 24 engaging the cam 14a of the sector 14, thereby to adjust the lateral amplitude of the needle bar.
In reference to FIG. 1, a feed regulator 55 as well known is swingably on a shaft 56 mounted to the machine hausing 2. The feed regulator 55 is normally biased in the clockwise direction by a tension spring 58, and is connected to the other end of the feed transmission lever 42 through a pin 57, a vertical rod 59 and a screw 60 which is operated by a nut 61 to adjust the reference angular position of the feed regulator 55. A transmission lever 62 is at the intermediate thereof turnably mounted on the support shaft 4, and has a pin 63 provided at one end thereof for engaging a buttonhole control cam groove (not shown) formed on the other side of the feed selecting cam 13, and is at the other end operatively connected to the feed regulator 55. The description of the buttonhole mechanism is omitted herein because this is not the subject matter of this application.
In reference to FIGS. 4 and 5, a transverse shaft 65 is rotatably mounted on the machine housing 2 and is rotated by an operating dial (not shown) for selecting the feed control cams 6. A selecting cam 66 with a cam lift 66a is secured to the feed control shaft for rotation therewith. An arm 67 is at the lower end thereof swingably mounted on a pivot 68 secured to the machine housing 2. The arm 67 is formed with a follower 67a normally in engagement with the selecting cam 66 as shown. A pin 71 is provided at the upper end of the arm 67. A transmission rod 69 is at one end connected to a pin 70 (FIG. 7) provided on the U-shape frame 25 and is at the other forked end connected to the pin 71 of the arm 67.
FIG. 6 shows a display plate arranged on the front face of the sewing machine, in which are indicated various patterns (a-s) to be selectively stitched. A pointer 73 is laterally moved to each of the patterns as the pattern selecting dial 8 is rotated to selectively stitch the same.
With the above mentioned structure of the invention, the operation is as follows; In reference to FIG. 4, if the pattern selecting dial 8 is rotated within the region of first revolution thereof as indicated by I in FIG. 6, the pin 29 of the switching rod 27 engages the radially outward cam 13b of the spiral cam groove 13a of feed selecting cam 13. The switching rod 27 is, therefore, displaced to the leftward position turning the switching cam 26 in the clockwise direction. In this condition, the follower 39 is pressed against the forward wall 26b of the switching cam 26. On the other hand, as the follower 67a of the arm 67 engages the radially reduced cam face of the selecting cam 66, the U-shape frame 25 is maintained in the horizontal position by the transmission rod 69. The follower 39 on the pin 32 is, therefore, held in the upper position and is disengaged from the feed control cam 6a. As is understood, as the pattern selecting cam 8 is rotated, the follower 19a is displaced relative to the pattern cams 5 and is engaged to one of the pattern cams 5 due to the action of the pattern selecting cam 12.
As shown in FIG. 5, if the selecting cam 66 is rotated and the radially enlarged cam lift 66a engages the follower 67a, the arm 67 turns in the counterclockwise direction, thereby to turn the U-shape frame 25 in the counterclockwise direction by way of the transmission rod 69. The pin 32 on the U-shape frame 25 is, therefore, displaced to the lower position from the upper position in FIG. 4. Thus the follower 39 is engaged with the feed control cam 6a, and the rotation of the feed control cam 6a is transmitted to the feed regulator 55 through the U-shape arm 31, the U-shape lever 34, the transmission lever 42 and the connecting rod 59, and thus the patterns (g-1) in FIG. 6 are selectively produced. In this case, the feed control cam 6a is designed to produce the ratio of feeding amount 1:1 in the forward and backward direction.
As shown in FIG. 8, if the pattern selecting dial 8 is rotated into the region of second revolution as indicated by II in FIG. 6, the pin 29 of the switching rod 27 engages the radially reduced cam face 13c of the feed selecting cam 13. The switching rod 27 is, therefore, displaced to the rightward position, thereby to turn the switching cam 26 in the counterclockwise direction. As a result, the cam lift 26a (FIG. 7) of the switching cam 26 engages the follower part 31a of the arm 31, thereby to disengage the follower 39 from the feed control cam 6a. Simultaneously the follower 39 is displaced from the front wall 26b to the rearward wall 26c through the sloped guide face 26d and pressed against the rearward wall 26c by the action of the spring 41. With a further rotation of the pattern selecting dial 8, the cam lift 26a is disengaged from the arm 31, and the follower 39 is allowed to engage the feed control cam 6b. Thus the patterns (m-r) are selectively produced. In this case, the feed control cam 6b is designed to produce the ratio of feeding amount 2:1 in the forward and backward directions.
In FIG. 6, the pattern (t) and the pattern of buttonhole stitches (u, v, w) are produced when the pin 29 of the switching rod 27 engages the cam face between the radially enlarged cam face 13b and the radially reduced cam face 13c of the feed selecting cam 13. The description of this is omitted herein because this is not the subject matter of the invention.
If the pattern selecting dial 8 is further rotated in the same direction, the pin 29 of the switching rod 27 comes to engage the cam face 13d (for the outline stitching) of the selecting cam 13, thereby to turn the switching cam 26 in the clockwise direction from the position in FIG. 8 to the position in FIG. 9. Then the pattern selecting dial 8 is stopped, and the cam lift 26e of the switching cam 26 engages the pin 37 of the U-shape lever 34 thereby to turn the latter in the clockwise direction around the shaft 32. As a result, the U-shape lever 34 is displaced to the position shown by a broken line from the position shown by a solid line as shown in FIG. 10, and accordingly the roller 36 on the upper end of the U-shape lever 34 is displaced in the arcuate slot 42c of the transmission lever 42, resulting in reducing the backward feeding amount.
This is explained in reference to FIG. 11. Namely when the pin 37 of the U-shape lever 34 engages the arcuate edge 26f of the switching cam 26 as shown in the solid line, the roller 36 engages the cam 42d of the arcuate slot 42c, which is substantially coaxial with the pivot pin 32. In this condition, the transmission lever 42 is swingable with a stroke S between the solid line and the dotted line due to the cooperation of the follower 39 and the feed control cam 6b. On the other hand, when the pin 37 engages the cam lift 26e of the switching cam 26 as shown in the broken line, the roller 36 engages the cam 42e of the arcuate slot 42c, which is of a radius slightly smaller than that of the cam 42d relative to the pivot pin 32. In this condition, the swinging stroke S of the transmission lever 42 is downwardly displaced by the difference ΔS. This swinging stroke of the transmission lever 42 is transmitted to the feed regulator 55, and the latter is accordingly operated to increase the forward feeding amount and decrease the backward feeding amount resulting in the feeding ratio approximately 2.5:0.5. In this case, the basic zigzag pattern cam 5a is selected during the rotational operation of the pattern selecting dial 8 for setting the outline stitches. It is also required to adjust the lateral amplitude of the needle approximately to 1 mm by operation of the amplitude adjusting dial 45. Thus the outline stitches (S) as shown in FIG. 6 is produced. | A sewing machine includes a main drive shaft rotatably mounted in said housing for vertically reciprocating a needle penetrating a fabric to produce stitches therein, a shaft extending transverse to the main drive shaft and rotatably mounted in the machine housing, a worm and a worm gear between said main drive shaft and the transverse shaft for rotating the latter at a speed smaller than the rotational speed of the main shaft, a plurality of pattern cams and a plurality of feed control cams mounted on the transverse shaft for rotation therewith. The sewing machine is further provided with a transmission arrangement operatively connected to a needle arrangement frame and having a first follower adapted to cooperate with a selected one of the plurality of pattern cams for controlling lateral swinging movement of the needle, a fabric feed regulator tiltably mounted in the machine housing for regulating the amount of movement of the fabric to be stitched in forward and rearward direction, and the transmission device for controlling tilting of the feed regulator including a second follower cooperating with a selected one of the feed control cams. A control shaft with a pattern selecting cam and a feed selecting cam is mounted in the machine housing, which is operative for moving the first follower into cooperative engagement with a selected one of said pattern cams and for moving the second follower into cooperative engagement with a selected one of the feed control cams. | 3 |
BACKGROUND OF THE INVENTION
1. Field Of the Invention
The present invention relates to asphaltic compositions for the preparation of bituminous draining or porous mixes and the preparation thereof.
2. Background
Conventional bituminous mixes are generally applied on most roads. However, the stresses to which these roads are subjected increase from year to year. Increasingly high axle loads and tire rolling pressures and the incessant increase in traffic have an unavoidable effect on the lifetime of these roads. More and more use is made of polymer-modified bitumens and of the development of new bituminous mix structures in order to combat the detrimental effects exerted by these traffic stresses.
The main technical objectives aimed at in the use of modified bitumens are:
(a) a greater resistance to permanent deformation;
(b) an improved low-temperature fatigue resistance; and
(c) an increase in the adhesive and cohesive properties.
For many years attempts have been made in highway engineering to employ industrial byproducts and, among these, recovered plastics originating either directly from the industry or from household waste. Plastics are of particular interest both from the viewpoint of cost and from an ecological viewpoint. In fact, this application enables the plastic waste to be permanently removed and does not present the risks related to the possible presence of polluting agents in gas emissions during incineration.
In addition to elastomeric modifiers such as SBS (styrene-butadiene-styrene) block copolymers or SBR (styrene-butadiene rubber) type or EVA (ethylene-vinyl acetate) plastomers, recent attempts have been made to utilize waste from cable manufacture, consisting essentially of LDPE (low density polyethylene) mixed with PVC (polyvinyl chloride) and polystyrene, or mixtures of polymers in household goods. European patent application number EP-332245-A, filed by Enichem having (i) the title "Bituminous Composition for Road Surfacing, (ii) a filing date of Feb. 24, 1989 and (iii) a publication date of Sep. 13, 1989 relates to this general area.
Bituminous draining mixes or porous asphalts have been the object of much interest. They are currently the preferred surfacing compositions for freeways and roads carrying heavy traffic. Their advantages are well known and include the following:
(a) Increased safety for the users: (i) elimination of the film of water on the highway preserves the ;adhesion of the tires to the ground, and this ensures a good trajectory and efficient vehicle braking; (ii) the driver is no longer dazzled by the multiple reflections of the many sources of light; and (iii) water spraying is eliminated.
(b) Reduction in noise: better environmental protection is obtained by virtue of an increase in the sound-absorption properties, in order to lower the perceived noise level.
(c) Reduction in costs: increased service life of the profiling and foundation layers by virtue of optimum water removal by the surface draining layer.
The manufacture of bituminous draining mixes calls for much care. The components forming part of the composition must have specific properties. The properties are obtained by the creation of channels within the thickness of the asphalt, and therefore by increasing the void volume. As a result of the open structure of the surface layer, the binder is subjected to stresses which differ from those encountered with traditional bituminous surface layers. The traditional compositions cannot therefore be employed. In order to combat these effects efficiently and therefore to ensure the durability of the draining layers it is necessary to have a sufficiently thick film of binder around each chip as well as good binder/granulate adhesiveness. Mechanical cohesion of the bituminous mix is traditionally obtained by the addition of new (SBS) or recycled (ground tire) elastomers, the aim being to obtain a binder which is extremely viscous and elastic at the service temperatures. Bituminous compositions in which the polyolefin concentration is higher than 5% by weight of bitumen give binders which are unstable in storage, greatly hardened and exhibiting phenomena of shrinkage on cooling.
SUMMARY OF THE INVENTION
The aim of the present invention is to provide an asphalt-based composition exhibiting the above-mentioned characteristics and permitting the massive use of recycled plastics such as HDPE (high density polyethylene).
The compositions of the present invention comprise essentially:
(a) an inorganic skeleton or aggregate comprising (by weight): from 79 to 88 parts of macadam of 6/17 particle size (between 6 and 17 mm), from 9 to 15 parts of sand of 0.08/2 particle size, from 3 to 8 parts of inert filling material of particle size smaller than 0.08, calculated to obtain a total of 100 parts;
(b) from 3.5 to 7 parts by weight of bitumen which has a penetration of between 65 and 150 tenths of mm at 25° C.;
(c) a first modifier chosen from the group comprising styrene-butadiene or styrene-isoprene copolymers or a mixture of such copolymers or of recycled tires, in a quantity corresponding to 2 to 7% by weight, calculated on the mass of the bitumen, optionally extended with 0 to 3% by weight of oil, calculated on the mass of the bitumen; and
(d) a second modifier chosen from the group comprising polyolefins, polyethylene terephthalate or a mixture of such polymers, in a quantity corresponding to 0.5 to 5 parts by weight:, without exceeding the quantity of bitumen.
Another object of the present invention is the use of these compositions for the manufacture of bituminous draining mixes or porous asphalts.
The invention further relates to a process for the preparation of bituminous draining mixes, this process being characterized in that the following are introduced into a mixer, at temperatures of between 130° and 185° C., preferably approximately 140° C. in industrial application and approximately 180° C. on the laboratory scale:
(a) an inorganic skeleton or aggregate comprising:
from 79 to 88 parts of macadam of 6/17 particle size,
from 9 to 15 parts of sand of 0.08/2 particle size, and
from 3 to 8 parts of inert filling material of particle size smaller than 0.08;
(b) either
(I) the combination of (i) bitumen which has a penetration of between 65
and 150 tenths of mm at 25° C., in a quantity corresponding to 3.5 to 7 parts by weight, and (ii) a first modifier chosen from styrene-butadiene copolymers, styrene-isoprene copolymers, recycled tires and mixtures thereof, in a quantity corresponding to 2 to 7% by weight, calculated on the mass of the bitumen, optionally extended with 0 to 3% by weight of oil, calculated on the mass of the bitumen; or
(II) 3.57 to 7.7% by weight, calculated on the inorganic mass, of a homogeneous modified bitumen-copolymer binder (styrene-butadiene or styrene-isoprene or a mixture of such copolymers), prepared in a vessel at 150°-180° C. from the components described under (i) and (ii); and
(c) a second modifier chosen from the group comprising polyolefins, polyethylene terephthalate and mixtures of such polymers, in a quantity corresponding to 0.5 to 5 parts, calculated on the inorganic mass.
The invention also relates to the use of rolling surfaces which have water draining properties, characterized by the composition described above.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The particle size, as employed here, should be understood as meaning that 80% , and preferably 90%, of the material must have a particle size larger than the lower value and 80%, and preferably 90%, a particle size smaller than the upper value.
In a preferred embodiment, the invention is characterized in that it consists of a mixture of approximately:
(a) 100 parts of inorganic skeleton,
(b) 5.1 pars of bitumen,
(c) 0.2 parts of SBS
(d) 2 parts of HDPE, preferably recycled.
In a preferred composition, the inorganic skeleton comprises 100 parts of:
(a) from 81 to 85 parts of macadam of 7/14 particle size;
(b) from 11 to 13 parts of sand of 0.08/2 particle size; and
(c) from 4 to 6 parts of filling material of particle size smaller than 0.08.
The inorganic skeleton is characterized by a gap grading and must have a composition and a particle size to provide an in-situ void content of between 15 and 30%, preferably between 15 and 25%.
The macadam must have a high hardness and a high resistance to polishing. The macadam which is employed for the production of such surfacings preferably corresponds to the following conditions:
accelerated polishing coefficient on the 7/14 fraction >45% (NBN standard B11-204)
micro Deval coefficient on the 10/15 category <10 (AFNOR NF standard P18-572 October 1978)
Los Angeles coefficient on the 10/14 category <15 (AFNOR NF standard P18573 October 1978).
Examples of useful macadam include flint, porphyry, quartzite and hard sandstone.
The filling material may be chosen from inert matter fines with a particle size smaller than 0.08, such as, for example, cement, secondary crushing fines, fly ash, clay dust or the like.
The bitumens are present in a proportion of 3.5 to 7 parts. The bitumens which can be employed for the production of such surfacings are bitumens for highway use, preferably distillation bitumens or reconstituted bitumens which have penetration values of between 65 and 150 dmm (according to ASTM standard D-5 or IP standard 49) and Ring and Ball values of between 40° and 59° C. (ASTM D-36 or IP 58). These bitumens may optionally be acidified and/or treated by the addition of antioxidants. The preferred bitumen grades have penetrations of between 80 and 100 dmm (dmm=0.1 mm).
The composition additionally comprises from 2 to 7% by weight of a butadiene-styrene elastomer, relative: to the bitumen (preferably 4 to 7% by weight). Particularly suitable copolymers include copolymers of the linear or radial SBR or SBS type. Styrene isoprene copolymers may aim be employed, for example SIS (styrene-isoprenestyrene block copolymers). These elastomers can be employed in new or recycled form, by themselves or mixed, extended with 0 to 3% of oil (oil introduced during the preparation of the SBS or oil incorporated during lube use of the recycled SBS in the form of fine rubber powder).
Finally, the composition comprises from 0.5 to 5 parts by weight, preferably 0.5 to 3, relative to the inorganic skeleton or aggregate, of a polyolefin or of polyethylene terephthalate, alone or mixed, new or recycled. The polyolefin is preferably chosen from the products resulting from the polymerization or copolymerization of ethylene or propylene, for example polyethylene (high or low density), polypropylene or ethylene-propylene-diene copolymers (EPDM copolymers). More particularly, when HDPE is employed, the quantities will be preferably limited to 0.5 to 3 parts by weight relative to the inorganic skeleton. The invention also makes it possible to recycle the dry packaging (plastic containers) after grinding. Packages soiled with aqueous or oily solutions (up to 30% by weight of the package) can also be employed, without preliminary washing. The preferred recycled product is in the form of shredded pieces of HDPE.
In general, a bituminous draining mix or porous asphalt can be prepared using two different methods, the first comprising (1) mixing the macadam with premodified binders. This type of preparation poses the problem of homogeneity of the binder, which must be freshly prepared and continuously stirred to avoid separation, and does not allow the incorporation of large quantities of polyolefins. The second method (2) comprises the extemporaneous preparation of the composition for draining bituminous mixes; this type of preparation, which forms the subject of the invention, has the advantage of avoiding the problems of separation in storage and allows large quantities of polyolefins to be incorporated, provided that the second modifier is premetered. The order of addition of the various components of the composition is not important.
The composition according to the invention has in particular the following advantageous properties:
(a) increased Marshall stability; and
(b) certain ecological impact: recycling of a large quantity of polyolefins.
The direct addition of HDPE to the asphalt makes it possible to recycle up to 3% HDPE relative to the mass of the asphalt, which represents 20 times the maximum quantity employable via the modified bitumen,
The following examples are given by way of illustration of the present invention and do not imply any limitation in their nature. The Marshall test (ASTM-D-1559-82) characterizes the properties of mechanical strength (stability) and plastic resistance (creep) but does not make it possible to measure validly all the mechanical properties of the draining asphalt, Only the stability measurements are significantly comparable.
EXAMPLES
All the experiments were conducted under the same operating conditions. The inorganic aggregates were screened on appropriate screens in order to obtain the necessary sizes and to remove adherent fine particles (wet screening). The inorganic aggregates were dried in the oven at 105°-110° C., according to size, to constant mass. Individually, starting with the filling material, the necessary quantities of materials (in increasing nominal sizes) were weighed cumulatively with an accuracy of 0.5 g. The aggregate was then mixed and heated in an oven to a temperature of 185° C. The quantity of binder or bitumen employed (2 kg) was heated to 180° C. and introduced with an accuracy of 0.1 g into the blending container preheated to the blending temperature (170° C.). The cold HDPE and the hot aggregate were then added. The material was mixed completely as rapidly as possible (maximum 135 seconds) to obtain a mix in which the bitumen was uniformly distributed.
Example 1
The bituminous mix tested corresponds to the following composition:
(1) inorganic skeleton (corresponding to the conditions described above)
7/14 Bande secondary crushed product: 82 parts,
0/2 Bande secondary crushed product: 14 parts (including 1 part of fines),
type I Ankersmit fines: 4 parts,
(2) 5.1 parts by weight of 81)/100 bitumen
(3) 0.2 parts by weight of Finaprene 401 powder (styrene-butadiene-styrene copolymer; 22% styrene), and
(4) as the second modifying agent: 1 part by weight of dry HDPE.
Example 2
The composition is identical with Example 1 in the case of the inorganic skeleton, the bitumen and the first modifying agent, but with the addition of 2 parts by weight of dry HDPE.
Example 3
The composition is identical with Example 1 in the case of the inorganic skeleton, the bitumen and the first modifying agent, but with the addition of 1 part by weight of oily HDPE (oil content: 26.1% relative to the HDPE).
Example 4
The composition is identical with Example 3 in the case of the inorganic skeleton, the bitumen and the first modifying agent, but with the addition of 2 parts of oily HDPE.
Comparative Example A
The bituminous mix tested corresponds to the following composition:
(1) inorganic skeleton: identical with Example 1, and
(2) 5.3 parts by weight of 80/100 bitumen. There is no modifying agent.
Comparative Example B
The composition is identical with Example 1 in the case of the inorganic skeleton, the bitumen and the first modifying agent, but without the addition of the second modifying agent.
Comparative Example C
The composition is identical with Example 1 in the case of the inorganic skeleton, the bitumen and the first modifying agent, but with the addition of 03 parts by weight of cellulose as the second modifying agent.
Comparative Example D
The bituminous mix tested corresponds to the following composition:
(1) inorganic skeleton: identical with Example 1, and
(2) 5.3 parts by weight of modified bitumen made up of 91% of 80/100 bitumen,
6% of Finaprene (registered mark) 480 (styrene-butadiene-styrene copolymer;
30% styrene; oil content: 50 parts per 100 parts of rubber) and 3% HDPE.
The quantities and the results are summarized in the table below, in which:
AD: direct addition of the SBS and modifying agent in parallel with the bituminous binder when coating the inorganic skeleton
PM: polymer modified bituminous binder including the modifying agent prepared before the coating of the inorganic skeleton
(*): oil content: 26.1%
401P: Finaprene 401 powder
480: Finaprene 480
The results in Table 1 show that the bituminous mixes obtained according to the invention exhibit better use properties.
TABLE 1__________________________________________________________________________Marshall tests on bituminous draining mixes First Second modifying modifying StabilityProcess Binder agent agent Void % (kN)__________________________________________________________________________EX 1 AD 80/100 bit. Finaprene Dry HDPE 21.78 6.20 5.1 part 401P 1 part 0.2 partEX 2 AD 80/100 bit. Finaprene Dry HDPE 20.80 8.65 5.1 part 401P 2 parts 0.2 partEX 3 AD 80/100 bit. Finaprene Oily 21.78 5.10 5.1 part 401P HDPE 0.2 part 1 part (*)EX 4 AD 80/100 bit. Finaprene Oily 19.60 5.55 5.1 part 401P HDPE 0.2 part 2 parts (*)EX A PM 80/100 bit. -- -- 21.72 3.40 5.3 partEX B AD 80/100 bit. Finaprene -- 22.22 4.80 5.1 part 401P 0.2 partEX C AD 80/100 bit. Finaprene Cellulose 20.55 4.50 5.1 part 401P 0.3 part 0.2 partEX D PM Modified -- -- 21.84 4.25 bitumen 5.3 part (91% 80/100 bit.; 6% Finaprene 480; 3% HDPE)__________________________________________________________________________ | Bituminous compositions are provided by mixing 100 parts of an inorganic skeleton or an aggregate with up to 7 parts of bitumen with a first modifier chosen from the group comprising styrene-butadiene polymers, styrene-isoprene polymers, recycled tires or any mixtures thereof, and a second modifier selected from the group comprising polyolefins, polyethylene terephthalate or any mixtures thereof. The present composition allows the utilization of large amounts of recycled plastics. | 2 |
BACKGROUND OF THE INVENTION
[0001] A. Field of the Invention
[0002] This invention relates to an archive management system for electronic mail messages and, more particularly, to methods and apparatus for archiving electronic mail messages and accessing archived messages.
[0003] B. Description of the Related Art
[0004] Many data processing systems permit transmission of electronic mail (“email”) messages between various users of the system. A standard feature of all email messages is the presence of a “header.” The header portion of an email message typically contains information about the source of the message, its subject, and its destination. The protocol for email headers over the Internet is defined in D. H. Crocker “Standard for the format of ARPA Internet text messages,” RFC 822 (August 1982) (“RFC 822”), which is incorporated herein by reference.
[0005] The transportation and delivery of email messages can be divided into two categories. The first category is the submission and receipt of messages between a client and an email post office. The second category is the routing of email messages from one post office to another.
[0006] There are currently two Internet standards for the submission and receipt of email messages between a client and a post office. One standard is known as “Post Office Protocol version 3” (“POP3”) and the other is known as “Internet Message Access Protocol version 4 revision 1” (“IMAP4rev1”). POP3 allows a client to connect to a post office server in order to check for new email messages in the client's mail account and to read header information. In order for a client to read an email message using the POP3 standard, the client needs to download the message to a local directory. The primary features of POP3 are described in M. Rose “Post Office Protocol—Version 3” RFC 1081 (November 1988) and M. Rose “Post Office Protocol—Version 3 Extended Service Offerings” RFC 1082 (November 1988), both of which are incorporated herein by reference.
[0007] IMAP4rev1 differs from POP3 in the sense that a client does not have to download an email message to the client's local directory from the post office server in order to read it. IMAP4rev1 allows a client to perform all of the client's mailbox functions with the message retained on the post office server. The features of IMAP4rev1 are described in M. Crsipin “Internet Message Access Protocol—Version 4rev1” RFC 2060 (December 1996), which is incorporated herein by reference. This particular feature of IMAP4rev1 is shared by many proprietary electronic mail systems, such as GroupWise from Novell, Inc. In GroupWise, when a post office receives a message for a given client, it is stored in a database in encrypted form in a mailbox designated for the client. The client is then notified that there is a new message. A configuration with all client mailboxes located on one post office server has the advantage of allowing an administrator to perform tasks associated with managing the server, including the deletion of old messages.
[0008] One of the most direct means of making a message available to a number of individuals is to send the message to each individual by including his/her electronic mail address in the header's destination address field such as the “To” or “CC” fields. One could also send the message to an automated mailing list manager that uses a mail exploder to turn a single alias for a distribution list into a series of individual mail addresses, or may forward the message to space dedicated to the distribution list on the post office server and accessible by all client members of the list. Mailing list managers such as LISTSERV of L-Soft International, Inc., listproc, and majordomo allow a client to subscribe or unsubscribe to a given mailing list.
[0009] POP3 and IMAP4rev1 also support public mailing lists, or distribution lists. When a message arrives and is addressed to a public distribution list, the post office server either uses a mail exploder to forward copies of the message to the mailboxes of list members or forwards a copy of the message to space specifically dedicated to the distribution list on the post office server that is accessible to all members. The post office server then notifies the respective clients that a message is being retained. The public distribution lists for these systems are generally maintained by an administrator.
[0010] The administrator also implements a message archive for archiving copies of incoming and/or outgoing messages for an enterprise. Due to the pervasiveness of email correspondence, an email message archive can contain thousands of messages. Because of the large number of designated clients, the overwhelming number of stored messages, and security concerns, access to such a message archive has been limited only to the administrator. Without completely reproducing the post office server and without the intervention of the administrator to impose some structure on the archive, an individual client cannot effectively sort the email messages located in the archive.
[0011] Thus, there is a need for a system and method that overcomes the shortcomings of existing electronic mail systems.
SUMMARY OF THE INVENTION
[0012] Systems and methods consistent with the present invention provide an automated manager for an electronic mail archive repository. A method of archiving electronic messages consistent with the present invention creates a repository that holds all electronic messages consistent with rules for archive storage. An interface allows clients to retrieve selected electronic messages from the repository based upon rules for limiting access to the repository.
[0013] In accordance with the principles of the present invention, methods and systems, as broadly described herein, comprise a message archive containing a plurality of messages, each having a client identifier and an archive token, and permit a requester access to selected messages in the message archive based on an identifier for the requester and consistent with rules for archive retrieval.
[0014] In accordance with another aspect of the present invention, methods and systems, as embodied and broadly described herein, comprise the steps of receiving a message, storing the message in a message archive when an indiction exits to archive the message, and permitting a requester access to selected messages in the message archive based on an identifier for the requester. Predetermined rules may be used to indicate when messages are to be archived and to control access to archived messages.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an implementation of the invention and, together with the description, serve to explain the advantages and principles of the invention. In the drawings,
[0016] [0016]FIG. 1 illustrates an exemplary distributed data processing system in which systems consistent with the present invention may be implemented;
[0017] [0017]FIG. 2 is a block diagram of an exemplary system architecture for a computer system with which the invention may be implemented;
[0018] [0018]FIG. 3 is a block diagram of an exemplary system architecture for a post office facility with which the invention may be implemented;
[0019] [0019]FIG. 4 is a block diagram of an exemplary system architecture for an archive facility with which the invention may be implemented;
[0020] [0020]FIG. 5 is a block diagram of an exemplary electronic mail message in accordance with the principles of the invention;
[0021] [0021]FIG. 6 is a flow chart of the steps a post office facility executes to sort incoming electronic mail messages and notify appropriate mail clients;
[0022] [0022]FIG. 7 is a flow chart of the steps performed by an archive facility to store electronic mail messages in a manner consistent with an implementation of the present invention; and
[0023] [0023]FIG. 8 is a flow chart of the steps performed by an archive facility to permit retrieval of stored electronic mail messages in a manner consistent with an implementation of the present invention.
DETAILED DESCRIPTION
[0024] Reference will now be made in detail to an implementation consistent with the present invention as illustrated in the accompanying drawings. Whenever possible, the same reference number will be used throughout the drawings and the following description to refer to the same or like parts.
[0025] Introduction
[0026] In general, methods and apparatus consistent with the present invention examine incoming electronic mail messages and generate an archive token consistent with rules for archive storage. Messages stored in an archive are accessible to clients based on identifying information stored in each message.
[0027] The Distributed System
[0028] An exemplary distributed system 100 with which methods and systems consistent with the present invention may be implemented is shown in FIG. 1. Distributed system 100 is composed of various components, including both hardware and software. Distributed system 100 includes a network 150 , such as a local area network (LAN), wide area network (WAN), or other mechanisms that connect a number of different data processing resources. Network 150 can also be connected to external networks 160 , such as the Internet. The resources in distributed system 100 include multiple mail clients 110 and 120 , an electronic mail post office 130 , and an archive facility 140 .
[0029] Distributed system 100 is structured to allow mail clients 110 and 120 access to the services of electronic mail post office 130 and to the services of archive facility 140 over network 150 . In addition, distributed system 100 allows electronic mail post office 130 to receive messages both from within network 150 as well as from external networks 160 . Finally, distributed system 100 allows electronic mail post office 130 to direct messages to archive facility 140 over network 150 . Although only two mail clients 110 and 120 , one post office 130 , and one archive facility 140 are depicted, one skilled in the art will appreciate that distributed system 100 may include additional clients, post offices or archive facilities in various configurations.
[0030] [0030]FIG. 2 depicts a computer architecture 200 associated with a mail client such as client 110 or 120 in greater detail. Computer architecture 200 includes a memory 210 , a secondary storage device 230 , a central processing unit (CPU) 240 , an input device 250 , and a video display 220 . Memory 210 includes a mail user agent 212 , a post office mail repository 232 .
[0031] As mentioned above, mail client 200 communicates with both electronic mail post office 130 and archive facility 140 over network 150 . Mail user agent 212 , post office client 214 and archive reader 216 are all computer programs that are executed by CPU 240 . Mail user agent 212 is a program, such as a word processor, that is used to prepare an electronic mail message for delivery by post office client 214 . Post office client 214 communicates with electronic mail post office 130 to obtain information about the messages retained on electronic mail post office 130 . Post office client 214 also manages the delivery of messages prepared by mail user agent 212 that are stored in the secondary storage device 230 . One skilled in the art will appreciate that if post office client 214 is based on the POP3 standard, then post office client 214 will assist in the transfer of mail messages retained at the electronic mail post office 130 to a local mail repository 232 . Finally, archive reader 216 is a program, such as a modified version of Netscape Navigator from Netscape Communications, Inc., that is executed by CPU 240 and facilitates communication between the client and archive facility 140 over network 150 .
[0032] [0032]FIG. 3 depicts a computer architecture 300 associated with post office facility 130 in greater detail. Computer architecture 300 includes a memory 310 , a secondary storage device 330 , and CPU 340 . Memory 310 includes a mail transfer agent 312 , a post office server 314 , a gateway manager 316 , and an archive storage manager 318 . Secondary storage device 330 includes rules for archive storage 332 .
[0033] As mentioned above, post office facility 300 communicates with mail clients 110 and 120 , and archive facility 140 over network 150 . Mail transfer agent 312 , post office server 314 , gateway manager 316 , and archive storage manager 318 are all computer programs that are executed by CPU 340 . Mail transfer agent 312 facilitates the transfer of messages between post offices, such as other post offices connected directly to network 150 or to post offices connected to external networks 160 . There are instances where the electronic mail post office is a proprietary system and where the electronic mail messages manipulated by the post office do not conform precisely to the RFC 822 standard, such as Microsoft Mail. In this case, a gateway manager 316 will operate to translate incoming or outgoing messages to the appropriate form. One skilled in the art will appreciate that, even with such messages, reference can be made to the RFC 822 standard without loss of generality.
[0034] Post office server 314 is the program that communicates directly with post office client 214 located on the client computer over network 150 . Post office server 314 notifies post office client 214 of new messages, and facilitates the transfer of message information to post office client 214 . Mail that is retained within the electronic mail post office for a particular client is stored in secondary storage device 230 .
[0035] Archive storage manager 318 is the program that communicates directly with an archive storage client located on archive facility 140 over network 150 . The current information which allows the archive storage manager to determine whether an archive token should be generated for or removed from a given message is stored in the rules for archive storage 332 . Archive storage manager 318 and the archive storage client operate together to transfer a copy of the message to be archived from the post office 130 to the archive facility 140 . For example, the archive storage manager 318 may open an archive storage manager socket to write to the archive facility.
[0036] [0036]FIG. 4 depicts a computer architecture 400 associated with an archive facility 140 in greater detail. Computer architecture 400 includes a memory 410 , a secondary storage device 430 , and CPU 440 . Memory 410 includes archive storage client 412 , and archive retrieval manager 414 . Secondary storage device 430 includes an archive repository 432 , and rules for archive retrieval 434 .
[0037] As mentioned above, archive facility 400 communicates with electronic mail post office 130 and mail clients 110 and 120 over network 150 . Archive storage client 412 and archive retrieval manager 414 are computer programs executed by CPU 440 . Also, archive storage client 412 communicates with the archive storage manager 318 on electronic mail post office 130 . Archive storage client 412 functions to transfer all messages determined by the archive storage manager 318 as intended for the archive facility to archive repository 432 . Archive retrieval manager 414 facilitates communication between archive facility 140 and mail clients 110 or 120 over network 150 . Archive retrieval manager 414 communicates directly with archive reader 216 and sorts messages stored in archive repository 432 and returns a results set to archive reader 216 based upon the rules for archive retrieval 434 .
[0038] As shown in FIG. 5, electronic mail message 500 has several fields that are structured according to RFC 822 . Electronic mail message 500 has a body 510 and header fields 520 , including a subject field 530 , a destination field 540 , and an origination field 550 . Destination field 540 of the mail header 520 contains an identifier for a mail client recipient 544 and may also contain an archive token 546 . The archive token 546 may be generated or validated by the archive storage manager 318 . It does not necessarily have to be included by the sender of the message. Destination field 540 may also contain an identifier for a distribution list 542 that can be resolved by a post office facility into a plurality of identifiers for individual clients (i.e., members of the distribution list). Finally, message 500 identifies a sender 552 .
[0039] The Process of Electronic Mail Delivery and Distribution Lists
[0040] [0040]FIG. 6 is a flow chart of the operations that a local electronic post office uses to direct mail to a given local account as well as to an archive facility consistent with an implementation of the present invention. Initially, an electronic message, having been directed to the post office from a network through a mail transfer agent 312 is received (step 610 ) and examined for local address information (step 620 ). If the destination field of the electronic message contains an identifier corresponding to a local client, for example, recipient ID 544 in destination field 540 (step 630 ), then the local post office notifies the local client that a message has arrived (step 635 ).
[0041] The post office facility may also contain a database of distribution lists. Each distribution list matches a group alias to a list of single client identifiers. The post office facility examines the destination field to see if it contains an identifier for a local distribution list (step 640 ). If the destination field contains such a distribution list identifier (step 640 ), then the local post office notifies all clients associated with the distribution list that a message has arrived (step 645 ). The post office facility retains a copy of the message to be accessed by the designated recipient(s) (step 650 ). When the post office facility retains a message, the message is stored in space dedicated to a single client or in space dedicated to the distribution list. The dedicated space is known as the mailbox.
[0042] As explained in connection with FIG. 5, destination field 540 of an incoming message may include a field for an archive token 546 , which is simply some type of indicator reflecting a determination that the message should be archived. Thus, step 660 in FIG. 6 determines whether an archive token is to be included or removed from the destination header field 540 . This step is performed by the archive storage manager 318 in accordance with the process of FIG. 7 and the rules for archive storage 332 . When the archive receives a message from the post office, it is stored in archive repository 432 depicted in FIG. 4. In one embodiment of the invention, the archive repository corresponds to the Local Mail Repository 232 of a mail client designated as an archive, where the archive token 546 may have the form archive@xz.corp.com.
[0043] The Archive Storage Manager
[0044] [0044]FIG. 7 is a flow chart depicting the operating steps of archive storage manager 318 consistent with the present invention. Initially, archive storage manager 318 accesses the current rules for archive storage 332 (step 710 ). In general, the archive rules define conditions for archiving messages. The rules may instruct the system to archive all messages or only a selected group(s) of messages based on, for example, the identity of the sender, the identity of-the recipient, the subject matter, the message contents, the message attachment (if any), or some combination of these items.
[0045] Next, the archive storage manager 318 checks the destination field 540 of the electronic mail message header 520 to determine whether the sender intended to archive the message by including an archive token in the field 540 (step 720 ). If the sender incorporated an archive token 546 in the message (step 720 ) and if the archive rules for storage 332 do not conflict with the sender's intention to archive the message (step 750 ), then the archive token 546 is retained (step 730 ). Likewise, if the sender did not incorporate an archive token 546 (step 720 ) but the message complies with the rules for archive storage 332 (step 740 ), then an archive token 546 is included in the message (step 750 ).
[0046] On the other hand, if the sender did not incorporate an archive token 546 (step 720 ) and the message does not comply with the rules for archive storage 332 (step 740 ), then no archive token 546 is included in the message. Also, if the sender incorporated an archive token 546 (step 720 ) but the rules for archive storage 332 conflict with and override the sender's intentions (step 730 ), then the archive token 546 is not included in the message (step 760 ). In this way, the archive storage manager 318 determines which messages passing through a post office facility are consistent with current rules for archive storage 332 and will be directed to the archive repository 432 for later retrieval.
[0047] The Archive Retrieval Manager
[0048] [0048]FIG. 8 is a flow chart depicting the operation of archive retrieval manager 414 consistent with the present invention. Initially, a client submits a request to the archive facility (step 805 ). Step 805 includes the delivery of a client identifier to the archive retrieval manager. For example, archive reader 216 may prompt the client to enter an identifier, or an identifier may be automatically routed to the archive retrieval manager by the network. Next, the archive retrieval manager 414 accesses the current rules for archive retrieval 434 (step 810 ). Next, archive retrieval manager 414 begins a search session (step 815 ). Upon the start of a search session, archive retrieval manager 414 checks to see if there are any unexamined messages in repository 432 for this search session (step 820 ). If there are none, then no further steps are taken and the session ends (step 855 ).
[0049] If there is an unexamined message (step 820 ), then archive retrieval manager 414 selects the unexamined message and applies the rules for archive retrieval (step 825 ). If the message satisfies the rules for retrieval (step 830 ), then the message is added to a results set (step 840 ). Otherwise, the message is not added to a results set for the search (step 845 ).
[0050] An example of a simple set of rules for archive retrieval might be that the recipient ID in the destination field of the message header matches the ID of the client requesting access. In such a case, the archive retrieval manager 414 parses the header field of a selected electronic mail message to determine the contents of the destination field. If the information contained in the destination field includes an identifier of the client requesting access, then archive manager 414 adds the message to a results set for that client. If, however, the destination field of a message does not contain an identifier for the client, then the archive retrieval manager 414 does not add that message to a results set.
[0051] Another rule for archive retrieval may be that the client requesting access is a member of a distribution list that is specified in the header field. Archive retrieval manager 414 then checks the destination field in order to see if it contains an identifier for a local distribution list. If there is an identifier for a local distribution list, then archive retrieval manager 414 checks to see if the client is a member of the distribution list. If the client is a member of the distribution list identified in the destination field, then the message is added to a results set for the client (step 840 ). Otherwise, archive retrieval manager 414 does not add the message to the results set (step 845 ) and checks to see if another unexamined message exists (step 850 ).
[0052] In this manner, the archive retrieval manager serially cycles through all of the unexamined messages that are present in the repository and makes available to the requesting archive reader 216 of the client all of those messages for which the client should be permitted access based on the rules for archive retrieval. Those skilled in the art will understand that other search processes may be used to locate electronic messages in the archive repository that satisfy a search criteria. Alternatively, the electronic messages in the archive repository may be indexed to permit application of another search algorithm.
[0053] Conclusion
[0054] Methods and apparatus consistent with the present invention store and manage access to electronic mail messages in an archive repository. The foregoing description of an implementation of the invention has been presented for purposes of illustration and description. It is not exhaustive and does not limit the invention to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practicing the invention. For example, instead of a linear search through the archive repository for a client's message, the archive manager may utilize a different, perhaps more efficient, search algorithm. In addition, messages may be archived based on archiving rules and without necessarily having to add an archive token to each archived message. Furthermore, although aspects of the present invention are described as being stored in memory and other storage mediums, one skilled in the art will appreciate that these aspects of the present invention can also be stored on or read from other types of computer-readable media, such as secondary storage devices, like hard disks, floppy disks, or CD-ROM; a carrier wave or other propagation medium from the Internet; or other forms of RAM or ROM. Accordingly, the invention is not limited to the above described embodiments, but instead is defined by the appended claims in light of their full scope of equivalents. | Systems and methods consistent with the present invention provide an automated manager for an electronic mail archive repository. A method of archiving electronic messages consistent with the present invention creates a repository that holds all electronic messages consistent with a set of rules for archive storage. An interface allows clients to retrieve electronic messages from the repository based upon rules limiting access to the repository. Methods and systems, as broadly described herein, comprise a message archive containing a plurality of messages, each having a client identifier and an archive token, and permit a requester access to select messages in the message archive based on an identifier for the requester and consistent with rules for archive retrieval. Additionally, methods and systems, as broadly described herein, comprise the steps of receiving a message, storing the message in a message archive when an indication exists to archive the message and consistent with rules for archive storage, and permitting a requester access to select messages in the message archive based on an identifier for the requester and consistent with rules for archive retrieval. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority of Provisional Patent Application Ser. No. 60/249,400 filed Nov. 15, 2000.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable
REFERENCE TO A “MICROFICHE APPENDIX”
Not applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to portable greenhouses and more particularly to a portable, wheeled greenhouse having an improved construction that includes a frame that supports a water containing tub or reservoir that has fittings for enabling water to be piped to and from the tub. A series of movable racks is supported by the frame above the tub and at a position that suspends pots from the racks and into the tub wherein the pots may extend into water and the plants receive water via osmosis from water contained within the tub.
2. General Background of the Invention
Several patents have issued for portable greenhouse arrangements. These include the following:
PATENT
ISSUE
#
TITLE
DATE
147,849
Fountain, Aquarium, and Flower-Pot Stands
02/24/1874
3,095,670
Seed Starter and Plant Propagator
07/02/1963
3,106,801
Portable Electric Greenhouse
10/15/1963
4,045,911
Versatile Horticultural Growth Apparatus
09/06/1977
4,316,347
Portable Solar Garden
02/23/1982
4,794,727
Wheel-About Greenhouse
01/03/1989
4,850,134
Growth Chamber With Solar Energy Absorber
07/25/1989
4,899,487
Storage and Display Receptacle Assembly
02/13/1990
5,095,649
Storage Receptacle Assembly
03/17/1992
5,448,853
Plant Growing Apparatus
09/12/1995
5,570,540
Seedling House
11/05/1996
5,675,932
Plant Growing System
10/14/1997
6,029,398
Multi-Compartmentalized Plant Container
02/29/2000
The Risacher U.S. Pat. No. 3,106,801 discloses a portable electric greenhouse that includes a small receptacle having a transparent cover that fits over the receptacle.
A wheeled storage and display receptacle assembly for display and/or storage of floral items is disclosed in the Brownlee U.S. Pat. No. 4,899,487.
A wheel-about greenhouse is disclosed in the Kevin Smith U.S. Pat. No. 4,794,727. The Smith patent includes a wheeled frame. A pair of wheels are attached to the frame for wheeling the device about. A clear cover fits the upper edge of the frame.
The Harman U.S. Pat. No. 5,448,853 discloses a portable plant growing cart that can accommodate one or more plant trays thereon. The cart is constructed of rigid frames which are pivotally connected together so as to aid the storage of the cart when not in use. A movable light source is supported from the separate frames above the trays at any desired elevation. Additionally, a fabric like reflective shroud is supported over both the light source and the cart so as to reflect light back towards the plant trays when desired.
A seedling house is disclosed in U.S. Pat. No. 5,570,540 issued to Womack. The seedling house includes a number of shelves that have openings for receiving pots.
BRIEF SUMMARY OF THE INVENTION
The portable greenhouse cart of the present invention provides a household size of greenhouse for use inside or outside the house in such as a Florida Room, screen room, patio, or in a garage or cellar. The cart provides most of the features of a free-standing greenhouse, however, in a size that may be conveniently utilized in restricted spaces, and freely moved to take advantage of natural sunlight, or, for other convenience, in moving about the inside quarters.
Fundamentally, the cart includes a watertight tub or pan mounted on wheels (such as bicycle wheels), disposed generally at one of the tray and legs (perhaps also including casters). In the inside periphery of the tub is disposed a rack (or racks) for holding seed flats, pots and the like, the rack(s) may be comprised of multiple assembleable preformed rods or slats having ends for detachable assembly into spaced holes which are set at predetermined positions coordinated such that the adjacent slats support standard sized seed flats and pots, with the rack(s) capable of being readily broken down and reassembled to accommodate different sized flats or pots.
In a preferred embodiment of assembleable racks, the slats have a projection resembling the shape of an arrowhead which may be closely and locally received into a rectangular or a round hole in an adjacent slat. Main framing slats (tray bars) may include an additional keying projection to be closely received by a notch disposed in the slat adjacent the spaced holes.
The tray or tub provides a fluid containing reservoir and is preferably adapted with a drain in the underside of the tray along with a water inlet connected to an internal watering system within the tray.
The internal watering system may include such as spaced nozzles activated by water pressure such that the dispensing nozzle rises out of the nozzle housing to spray a limited region of the tray. Watering nozzles similar to smaller lawn sprinklers are preferred.
The tray may be fitted with an overhead framework for supporting an awning like cover, preferably transparent or translucent, to enable sunlight or artificial light (from an included fixture) to flood the plants and encourage seed germination and plant growth. For further enhancing the growth properties of the cart, a low power heating coil may be disposed adjacent the cart underside to provide supplemental heating should heating be desired.
The portable greenhouse and plant cart of the present invention is engineered and designed to provide improved growth and environmental control for germination of flower, vegetable, and herb seeds. This allows for a great head start on the growing season in residential gardens. Particularly in climates with a late spring, this product is also designed to serve alternatively as a patio vegetable, herb, and flower cart garden. The portable greenhouse of the present invention can also be used in a garage or outside building for storing ferns and potted plants through winter months.
Anyone who has ever gardened agrees that there is joy in nurturing a tiny seed and watching it grow into a robust plant. The portable greenhouse of the present invention, with its controllable climates, is ideally suited for starting plants from tiny little seeds such as perennials, annuals, herbs, and vegetables.
The apparatus of the present invention features a light-weight frame that can be constructed of such as durable lightweight pipe (e.g., one (1) inch PVC) with elbows and tees to form, for example, a 2′×4′ or 4′×6′ cart with bicycle size wheels. The one (1) piece bottom pan forming the tub can be formed from hard plastic to prevent corrosion or breakage. Tray holders are preferably formed from hard plastic with adjustable spacing rods for seed flats and pot holders.
In its preferred embodiment, the portable greenhouse has water hose and electrical heat hookups, a clear plastic cover, and an adjustable light located on top of the cart. A heat cord in the bottom of the pan with temperature control would keep the cart at a consistent temperature based on ambiance. The portable greenhouse temperature controls need to be set at 70-75 degrees F. for seedling and propagating cutting; a warm 65 degrees F. for the germination of most seeds; and 80 degrees F. for tropical varieties.
The cart is preferably about thirty inches high and makes gardening easy for everyone. This is the same height as a desk, and is ideal height for sliding a chair underneath while working on plants. This height would make gardening available for the physically challenged and elderly.
For the germination of seeds each 2′×4′ cart could hold four seed flats. Each flat could hold eighteen three packs, six six packs, six nine packs, eighteen two packs, and eighteen 3½×3½″ pots. The eighteen three packs and the six nine packs could yield fifty-four plants per flat and a total of 216 plants per cart. The six six packs and the eighteen two packs could yield thirty-six plants per flat and a total of 144 per cart. The eighteen 3½″×3½″ pots could yield eighteen plants per seed flat and a total of 72 plants per cart.
The 4′×6″ cart could hold twelve seed flats. The eighteen three packs and six nine packs could yield fifty-four plants per seed flat for a total of cart 648 plants per cart. The six six packs and eighteen two packs could yield thirty-six plants per flat and a total per cart of 432. The eighteen 3 ½×3½″ pots could yield eighteen plants per seed flat and a total for cart of 216 plants. A user could have half flowers and half vegetables or other desired combination.
When using the cart as a patio flower, vegetable and/or herb garden, a gardener starts with seeds or small plants. Plants are repotted in larger pots and placed in the cart on the patio, screen porch, etc. of home or apartment.
A drain valve is provided in the tub or bottom pan to drain off excess water from the cart. A garden hose will hook up to the valve so that water can be drained into a sink or outside if the cart is to be used inside. When using the cart outside, water can be drained into flower beds or onto the ground.
The watering system includes an adjustable sprinkler head that can be positioned in the center of the cart. With PVC pipe extensions the sprinkler head rises above the potted plants. Simply twist the top of the sprinkler head to adjust the water flow radius.
The wick system is another watering method that can be used for certain plants (e.g., saintpaulias). The wick watering system is made up of two parts: (1) the upper section serves as a flowerpot and (2) the lower serves as the saucer-reservoir, holding water and liquid fertilizer. The wicks in the bottom of the pots operate on the principle of the oil lamp, drawing water instead of oil. The wick pots offer a healthful and convenient way to grow African-violet.
The top of the cart features an adjustably positioned light that is removable and swing-away. With different types of light attachments the light could range from full spectrum lighting to a heating lamp.
The cover for the portable greenhouse can be manufactured from lightweight clear durable plastic, which allows light penetration while providing protection from insects and birds. The lightweight plastic material would also help reduce heat and moisture loss. The cover can be removed after seed germination, converting the portable greenhouse into a plant cart for a patio garden. The lightweight cover is preferably easily folded and stored in the tool holder on front of the cart or in a storage area. A flap located on top of the cover with a Velcro® fastener addresses ventilation needs.
The adjustable tray holders can be manufactured from a hard plastic to prevent corrosion or breakage. The tray connection bar ends can be tapered in both directions, allowing them to easily lock in place when a short taper is passed through the rail. The connection bars can have holes to accept the taper lead-ins and snap taper, plus being notched to have a flash top so the cups or pots can sit evenly on all sides.
The bar rail, which holds the plants, is designed to rest on the pipe frame on both ends and have connection bar holes on about two inch centers. The completed tray holders can be quickly and easily converted to hold all standard cups, pots, and seed flats and can be adjusted by the customer for different uses.
The portable greenhouse and plant cart of the present invention is designed for easy use and assembly. It can be entirely of plastic materials to prevent breakage and corrosion, and enabling easy cleanup after use. Large wheels can make moving the cart effortless, and a large handle on the front of the cart can also aid in moving the cart. The holder or tray on front of the cart will hold small gardening tools and gloves.
The greenhouse cart of the present invention is engineered to make gardening or the germination of plants easier for everyone. It takes away the hassle of traditional gardening methods for those individuals who may have trouble handling the work load, or simply do not have a lot of gardening space and for people who are just looking for an easier method.
The tray holder can be manufactured from a hard plastic to prevent corrosion or breakage while allowing for some flexibility. It can be made in different colors to easily identify the lengths. Tray connection bars ends are preferably tapered in both directions to allow for an easy lead-in and snap to lock connection. It locks in place when passed the short taper on the inside.
The connection bars have holes to accept the taper lead-in and snap taper, plus it is notched to have a flush top so the cups or pots can set evenly on all sides.
The bar rail is designed to rest on the PVC pipe frame on both ends and have connection bar holes on about 2 inch centers. Two of the connection bars can be used as a handle on both ends.
The completed tray holder can be quickly and easily converted to hold all standard cups, pots and flats plus can be customer adjusted for special uses.
BRIEF DESCRIPTION OF THE DRAWINGS
For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein:
FIG. 1 is a perspective view of a preferred embodiment of the apparatus of the present invention;
FIG. 2 is a side perspective view of a preferred embodiment of the apparatus of the present invention;
FIG. 3 is an end perspective view of a preferred embodiment of the apparatus of the present invention;
FIG. 4 is side perspective view showing the under side of a preferred embodiment of the apparatus of the present invention;
FIG. 5 is a partial perspective exploded view of a preferred embodiment of the apparatus of the present invention;
FIG. 6 is a partial perspective view of a preferred embodiment of the apparatus of the present invention;
FIG. 7 is a partial perspective exploded view of a preferred embodiment of the apparatus of the present invention;
FIG. 8 is a fragmentary sectional view of a preferred embodiment of the apparatus of the present invention;
FIG. 9 is a partial elevation view of a preferred embodiment of the apparatus of the present invention showing the connecting bar and bar rail prior to assembly;
FIG. 10 is a partial end view of a preferred embodiment of the apparatus of the present invention illustrating one of the bar rails; and
FIG. 11 is a partial perspective view of a preferred embodiment of the apparatus of the present invention illustrating two of the racks;
FIG. 12 is a perspective view with the cover exploded, of an alternative embodiment of the apparatus of the present invention;
FIG. 13 is an end view of the alternative embodiment of the apparatus shown in FIG. 11;
FIG. 14 is a partial pictorial view of the tub of the apparatus shown in FIG. 11; and
FIG. 15 is an elevational view of the apparatus shown in FIG. 11, with a portion of the cover cut away.
FIG. 16 is a partial perspective view of an alternative embodiment of the apparatus of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1-11 show a preferred embodiment of the apparatus of the present invention designated generally by the numeral 10 in FIGS. 1 and 2. In FIGS. 3, 4 , 5 and 6 , the apparatus 10 of the present invention is shown with the cover removed for clarity.
Portable greenhouse cart apparatus 10 has a frame 11 that includes a large tub or reservoir 17 manufactured for example of plastic or metallic construction and supported by legs 12 , horizontal braces 13 , vertical members 14 and horizontal braces 15 that can function as axles. A pair of spaced apart wheels 16 are attached to frame 11 opposite handle 28 .
Tub 17 is preferably a liquid containing vessel or reservoir that can be manufactured of any material that will hold water or a mixture of water and liquid fertilizer. The tub 17 has a bottom wall 18 and a plurality of side walls 19 , 20 as well as end walls 21 , 22 . One of the side walls 19 , 20 or end wall 21 , 22 can include a fitting 23 that communicates with inlet flow line 24 . Flow line 24 is provided for adding water to the interior of tub 17 such as during a filling of the tub such as by hose 24 ′ attached to fitting 23 or when it is desired that water should be sprayed upon potted plants that are growing in pots 38 , 39 supported by racks 34 , 35 .
A drain fitting 25 can be used to drain water from tub 17 if it is desired to water plants using spray head 26 and not through wicking action. As with fitting 23 , drain fitting may be connected to a hose 24 ′ (not shown) so that drain water may be directed to a convenient disposal area.
Spray head 26 can be mounted at one end portion of inlet flow line 24 , preferably a riser section that positions the spray head 26 above any potted plants that are growing in pots 38 , 39 on racks 34 , 35 . If desired for additional coverage, multiple spray heads 26 may be positioned at selected locations in tub 17 .
A heater 27 can be provided for heating tub 17 and/or water that is contained within tub 17 . Conventional electrical strip heaters such as low wattage flexible strips available from such as Watlow Electric Manufacturing Company or Omega Engineering, Inc. may be disposed below tub 17 as illustrated in FIG. 4 . Selection of a particular strip will be influenced by the amount of heat to be supplied to tub 17 as well as the material of which it si composed.
Handle 28 is positioned opposite wheels 16 and can support storage tray 29 as shown in FIG. 1 .
A frame 31 is provided that supports translucent cover 32 . Cover 32 can be translucent or transparent as desired. The illustrated cover 32 is a unitary structure of clear plastic such as Lexane® polycarbonate material available from General Electric Company, Inc. Alternatively, cover 32 may be translucent should it be desirable to shield the contents of cart 10 from view. Likewise, individual sheets of plastic material may be attached to selected frame members 31 , either permanently or with detachable means such as screws, clips and clamps. Also, within the scope of the present invention, cover 32 may be a flexible clear plastic or fabric which is conveniently draped over frame 31 .
A lamp 33 is supported above translucent or transparent cover 32 . The lamp 33 is preferably mounted upon a swivel or pivoting post so that the lamp 33 can be rotated away from cover 32 such as when the cover 32 is to be removed.
Frame 31 is comprised of a number of framed parts that include legs 47 , horizontal supports 48 , vertical sections 49 , inclined sections 50 , and horizontal sections 51 as shown in the drawings.
The frame 31 can be a unitary structure that can be lifted from tub 17 , as in the preferred embodiment. The leg portions 47 of frame 31 can simply rest upon the bottom 18 of tub 17 . Framed parts illustrated are of such as ½ inch to 1 inch diameter PVC pipe using connectors such as elbows, “T”s and sleeves. Alternatively, metal tubing of steel, aluminum and similar materials may be utilized as well as analogous angular or strip materials. Preferable materials are those light in weight such that the overall weight of cart 10 does not impeded its movement.
A plurality of racks 34 , 35 , preferably of different internal size for accommodating pots of different diameters are supported by frame 31 and more particularly by the horizontal supports 48 . Each rack 34 , 35 has respective openings 36 , 37 of differing dimensions so that a plurality of racks 34 , 35 , or additional racks can carry a number of pots 38 , 39 (or other pots) of differing diameters.
Each rack 34 , 35 is constructed of bar rails 40 and connecting bars 44 . This construction of racks 34 , 35 can best be seen in FIGS. 5-11. In their preferred embodiment, each bar rail 40 has end portions with notches 41 that fit the horizontal supports 48 of frame 31 . Openings 42 in bar rails 40 receive pegs 45 of connecting bars 44 . In the preferred embodiment illustrated in FIG. 11, peg 45 includes a detent 45 ′ which cooperates with the bar rail 40 at opening 42 to retain peg 45 therein. Each bar rail 40 has notches or recesses 43 that receive horizontal projections 46 that are at the end portions of connecting bars 44 as shown in FIGS. 7-11. The bar rails are connected together using a plurality of connecting bars 44 as shown in FIGS. 7-9 wherein the pegs 45 of connecting bars 44 fit into in a snap fashion the openings 42 in bar rails 40 . As may be best seen in FIG. 11, connecting bars 44 may be fabricated of differing lengths as illustrated, such that openings 38 may be readily varied in size to accommodate different sized pots.
In the embodiment of racks 34 , 35 illustrated, openings 42 are spaced at a preselected distance x which is then also the operative length of the smallest cross or connecting bars 44 . The distance x is selected to be slightly smaller than the diameter of a planting pot to be ultimately positioned into racks 34 , 35 . Additional sizes of cross or connecting bars 44 are provided which are of an operative length of such as 2× and 3×. By this coordinated sizing, racks 34 , 35 may be readily fabricated from bar rails 40 and connecting bars 44 of differing sizes to accommodate larger pots as well.
Completed pot racks 34 , 35 are shown in FIG. 16 . Each completed pot rack 34 , 35 includes at least a pair of spaced apart bar rails and a plurality of connecting bars 44 . Handles 52 can be fitted to the end portions of each bar rail 40 . The handles 52 have a similar configuration to the connecting bars 44 , so that projections 46 and pegs 45 of each handle 52 fit the recess 53 and opening 54 that are provided at opposing ends of bar rail 40 .
Each of the racks 34 , 35 provides preferably a plurality of openings, each for receiving a pot. These openings are smaller for the rack 34 wherein the openings are designated generally by the numeral 36 . These openings are larger for the rack 35 , designated by the numeral 37 . Openings 36 , 37 can thus be provided of a variety of dimensional configurations for accommodating either rounded or squared pots, or pots of other shapes, as well as pots of differing diameters and dimensions.
FIGS. 12-15 illustrate an alternative embodiment of the portable greenhouse cart apparatus 10 of the present invention. As illustrated in FIGS. 12 and 15, the frame 11 , legs 12 , braces 13 vertical members 14 and tub or reservoir 17 illustrated in the FIGS. 1-11 are incorporated into a molded chassis, wherein legs 12 ′ are an integral part of chassis 10 ′. Likewise, the tub or reservoir 17 ′ is a molded unit, affixed to chassis 10 ′ as by welding, adhesives or mechanical fasteners, according to the materials chosen for the chassis, i.e., plastics or metal. By forming an integral chassis, a storage area 55 may be incorporated, including a closable door 56 to secure the contents of storage area 55 when not in use.
The remaining aspects of chassis 10 ′ are similar to those previously illustrated and described. FIG. 14 illustrates tub or reservoir 17 ′ including elongated groves 57 in which heating elements as previously described may be disposed.
The following is a list of suitable parts and materials for the various elements of the preferred embodiment of the present invention.
PARTS LIST
10
greenhouse cart apparatus
10′
integral chassis
11
frame
12
leg
12′
integral leg
13
horizontal brace
14
vertical member
15
horizontal brace
16
wheel
17
tub
17′
integral tub
18
bottom
19
side wall
20
side wall
21
end wall
22
end wall
23
fitting
24
inlet flowline
24′
hose
25
drain
26
spray head
27
heater
28
handle
29
storage tray
30
upper edge
31
frame
32
translucent cover
33
lamp
34
rack
35
rack
36
opening
37
opening
38
pot
39
pot
40
bar rail
41
notch
42
opening
43
recess
44
connecting bar
45
peg
45′
detent
46
projection
47
leg
48
horizontal support
49
vertical section
50
inclined section
51
horizontal section
52
handle
53
recess
54
opening
55
storage area
56
door
57
groove
The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims. | A portable, wheeled greenhouse includes a chassis that can be wheeled, having upper and lower end portions. The upper end portion includes a tub-like reservoir with side walls and a bottom wall. One or more racks are supported upon the combination of wheeled chassis and tub and above the bottom of the tub so that each rack is sized and shaped to support and suspend a plurality of potted plants above the bottom, yet close enough to the bottom of the tub so that any water that is optionally contained within the tub contacts the supported pots and waters them via wick action. A translucent or transparent canopy fits about the combination of tub and chassis, the canopy can include a support frame with a cover. | 0 |
BACKGROUND
[0001] The subject application relates generally to a control sensor assembly for an agricultural harvester. In particular, the subject application provides an improved mount for the control sensor assembly that utilizes a single mount to perform multiple functions.
[0002] During a harvesting operation, a header at the front of a harvester cuts ripened crops from the field. The header is attached to the front of the harvester and includes mechanisms, for example, for cutting crops, gathering crops and depositing crops into a feederhouse. The objective of the agricultural harvester is to gather as much crop material as possible when traveling across the field. This can become increasingly difficult as the ground contour can vary. As a result, header height control systems are utilized to raise, lower and tilt the header in order to maximize the harvester's crop yield.
[0003] Generally, a header height control system utilizes a control sensor assembly to accurately detect the contour of the ground for changes in landscape i.e., its position relative to the ground as it travels over uneven terrain. Conventional control sensor assemblies require the use of multiple sensors and parts which consequently requires a larger number of steps and complexity in the installation process. During installation, operators have to ensure that the control sensor assembly is properly oriented for connection to the header height control system. If assembly and installation is done incorrectly, this could lead to increased delays and maintenance costs, improper operation of the harvester, economic loss, as well as damage to components of the agricultural harvester.
[0004] Therefore, there is still a need for an improved mount for a control sensor assembly that reduces potential for human error and performs multiple functions with less assembly parts and requires fewer steps to install the assembly. The subject application addresses the foregoing issues of conventional control sensor assemblies.
BRIEF SUMMARY
[0005] In accordance with an aspect, the subject application provides a control sensor assembly for an agricultural harvester. The control sensor assembly comprises a linkage, a bushing, a mount and a sensor. The linkage is for connection to a header height control system. The bushing includes a first end connected to the linkage and a second end housing a magnet. The mount includes a body having a through hole extending from a first surface to a second surface opposite the first surface for receiving the bushing and a first rotational stop about the first surface and adjacent the through hole. The sensor is mounted to the mount and spaced from the second end of the bushing.
[0006] In accordance with another aspect, the subject application provides a header of an agricultural harvester. The header comprises a frame, a linkage and a control sensor assembly mounted to the frame. The control sensor assembly includes a bushing, a mount and a sensor. The bushing includes a first end connected to the linkage and a second end housing a magnet. The mount includes a body having a through hole extending from a first surface to a second surface opposite the first surface for receiving the bushing and a first rotational stop about the first surface and adjacent the through hole. The sensor is mounted to the mount and spaced from the second end of the bushing.
[0007] In accordance with yet another aspect, the subject application provides a mount for mounting a sensor to a header of an agricultural harvester. The mount comprises a body and first and second spaced apart guide surfaces. The body includes a counterbore and a through hole extending through the counterbore from a first surface of the body to a second surface of the body opposite the first surface. The body further includes an anterior surface adjacent the counterbore and extending substantially transverse to the first surface. The first and second spaced apart guide surfaces extend from the first surface. Each guide surface is positioned adjacent a lateral side of the counterbore and the first guide surface includes an engaging surface at an angle relative to an engaging surface of the second guide surface. The first and second guide surfaces each have a mounting surface and an opening through which a fastener is passable for securing the mount to the header. The mounting surface is substantially parallel to and spaced from the first surface for engaging the header.
[0008] The subject application provides a unique mount for a non-contact header height control sensor that uses one piece to perform multiple functions. The main block will control shaft end-play, act as a rotational stop, serve as the sensor mount, and mount the entire system to a machine that is using header height control (HHC). A non-contact sensor is a sensor in which the magnet is a separate piece from the sensor body itself unlike a one piece sensor in which everything is contained within the sensor body. The non-contact sensor needs to maintain a specified air gap between the magnet and the sensor body for proper functionality. Thus, a system is needed to control the end play of the magnet that is attached to the rotating shaft and consistently hold the sensor body at the appropriate location. Along with the end play, the rotational motion needs a bearing surface to allow free rotation of the shaft. The system also needs a rotational stop so that during assembly it cannot be assembled incorrectly. The system is also simpler than what is currently used. It has fewer parts and would be used multiple times in comparison to once per header.
[0009] Conventional header height control systems consist of a laser formed piece with two machined hubs welded to it, two bushings pressed into each hub, and two snap rings. The assembly is for one side of the machine and would have a mirror image on the opposite side. The parts in the disclosed system of the subject application would be a machined block and a plastic bearing surface. The subject application's assembly can be used multiple times e.g., four times, on the header whereas the current system has a left and right and is only used once per head.
[0010] In the subject application, the main block of the system is machined so that from the face of one side to the other side, the distance will be consistent allowing the air gap between the magnet and the sensor body to be precisely controlled. Additionally, the machined rotational stops will automatically be formed into the block. The rotational stops will help with the installation by forcing the installer to properly orient the block with respect to the side of the machine, since this single block will be able to be used in multiple locations on the machine. The plastic bearing surface will also hold multiple functions. On one side of the plastic part, there will be a machined spot for the magnet to be attached to. The opposite end will have another machine feature that will act as a receiver that will accept a driver feature on the header height control linkage. This all can be assembled first and then assembled to the machine. The machine will act as the stop that does not allow the magnet to get farther away from the sensor.
[0011] In addition to controlling the air gap, the resultant advantages of the subject application include having fewer parts that need to be maintained. In conventional header height control systems, the auger and draper head use different parts that perform the same function along with needing a left and right portion which means four separate assembly part numbers, not including sub parts that go into the assembly. The subject application would allow for the same assembly parts to be used on both heads for the left and right sides, reducing four separate assembly part numbers to one. The subject application's system would require fewer processes to make the assembly than currently is required. Conventional header height control systems require a laser process, forming process, machining process, welding process and painting while the subject application would only need a machining process or a molding process (for a plastic mount) to manufacture the mount. The built in stops will require the assembler to only assemble the subject application in the correct way. The current system is mounted using two bolts which would allow the operator to incorrectly assemble it if they were not paying attention.
[0012] In sum, the subject application provides an improved mount for a non-contact header height control sensor that performs multiple functions including controlling shaft end-play, acting as a rotational stop, serving as a sensor mount, and mounting the entire system to the machine that is using header height control. The resultant advantages of such a mount are that one single part is performing multiple tasks while controlling the air gap needed for the two piece sensor.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0013] The foregoing summary, as well as the following detailed description of the several aspects of the subject application, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the subject application, there are shown in the drawings several aspects, but it should be understood that the subject application is not limited to the precise arrangements and instrumentalities shown.
[0014] In the drawings:
[0015] FIG. 1 is a side view of a frame of a header of an agricultural harvester in accordance with an aspect of the subject application;
[0016] FIG. 2 is a bottom, front perspective view of a control sensor assembly in accordance with an aspect of the subject application;
[0017] FIG. 3 is an exploded bottom perspective view of the control sensor assembly of FIG. 2 ;
[0018] FIG. 4 is an exploded top perspective view of the control sensor assembly of FIG. 2 ;
[0019] FIG. 5A is a lateral cross sectional view of the control sensor assembly of FIG. 2 ;
[0020] FIG. 5B is a coronal cross sectional view of the control sensor assembly of FIG. 2 ;
[0021] FIG. 6 is a bottom, front perspective view of a mount of the control sensor assembly of FIG. 2 ;
[0022] FIG. 7 is a top perspective view of the mount of FIG. 6 ;
[0023] FIG. 8 is a coronal cross sectional view of the mount of FIG. 6 ;
[0024] FIG. 9 is a perspective view of a linkage and bushing of the control sensor assembly of FIG. 2 ; and
[0025] FIG. 10 is a side perspective view of a header of an agricultural harvester illustrating a header height control system applicable to the subject application with various components omitted for purposes of illustration.
DETAILED DESCRIPTION
[0026] Reference will now be made in detail to the various aspects of the subject application illustrated in the accompanying drawings. Wherever possible, the same or like reference numbers will be used throughout the drawings to refer to the same or like features. It should be noted that the drawings are in simplified form and are not drawn to precise scale. In reference to the disclosure herein, for purposes of convenience and clarity only, directional terms such as top, bottom, left, right, above, below and diagonal, are used with respect to the accompanying drawings. Such directional terms used in conjunction with the following description of the drawings should not be construed to limit the scope of the subject application in any manner not explicitly set forth. Additionally, the term “a,” as used in the specification, means “at least one.” The terminology includes the words above specifically mentioned, derivatives thereof, and words of similar import.
[0027] “About” as used herein when referring to a measurable value such as an amount, a temporal duration, and the like, is meant to encompass variations of ±20%, ±10%, ±5%, ±1%, or ±0.1% from the specified value, as such variations are appropriate.
[0028] Referring now to the drawings, wherein aspects of the subject application are shown, FIG. 1 illustrates several features of a frame of a header of an agricultural harvester according to the subject application. For purposes of illustration only and not by way of limitation, the header will be described e.g., as a header with a flexible cutter bar assembly, but can alternatively be any other header having a height control sensor. In addition to the frame, the header includes mechanisms for cutting crops, gathering crops and delivering crops to the agricultural harvester and is positioned relative to a ground surface upon which the agricultural harvester travels.
[0029] In FIG. 1 , there is shown a control sensor assembly 12 mounted to a side of a frame 10 of a header which can be attached to the front or anterior end of a combine or similar agricultural harvester (not shown). The frame 10 serves generally as a chassis for the header for supporting the various components of the header which are attached thereto. The header can include, among other components, a cutter bar. Such components of the header are known and therefore a detailed description of their structure, function and operation is not necessary for a complete understanding of the subject application. However, headers applicable to the subject application are disclosed in U.S. Pat. Nos. 7,950,212; 7,222,474; and 4,414,793, the entire disclosures of which are incorporated by reference herein for all purposes.
[0030] The cutter bar severs crops as the header of the agricultural harvester travels over the field. The crops are then conveyed towards other downstream components of the agricultural harvester, e.g., auger or feeder (not shown). During operation, the cutter bar is designed to have flexibility in order to accommodate and conform generally to changing ground contours at different locations of the field. As a result, a reliable ground sensor is required to serve as indicators of ground contour changes to adjust the height position of the header and its components.
[0031] A control sensor assembly 12 is configured and operable according to the teachings of the subject application, for following and sensing ground contour changes and outputting signals representative thereof to a header height control system 11 ( FIG. 10 ) of an agricultural harvester. The control sensor assembly 12 allows the header height control system 11 to raise or lower the header as required for maintaining the cutter bar at a desired level above the ground.
[0032] Referring now to FIGS. 2-5 , there is shown a preferred embodiment of the control sensor assembly 12 in accordance with the subject application. The control sensor assembly 12 includes a linkage 14 , a bushing 16 , a mount 18 and a sensor 20 . The linkage 14 connects the control sensor assembly 12 to the header height control system 11 in a conventional, well-known manner in the art. In accordance with an aspect, the linkage 14 has a proximal end with an aperture configured to receive a shaft 22 connecting the linkage to the bushing 16 . Preferably, the shaft 22 has a circular shaped first end corresponding to the aperture of the linkage 14 and an angular shaped second end e.g., a parallel piped shaft, opposite the first end. The angular shape of the second end corresponds to a slot 24 in the bushing 16 for connecting the linkage 14 and bushing 16 . As such, owing to the corresponding fit between the angular shaped second end and the female end of the bushing, the bushing will rotate correspondingly with rotation of the linkage about an axis defined by the shaft 22 . The linkage 14 also has a distal end with an aperture for adjustably connecting the linkage to the header height control system. FIG. 9 shows an isolated perspective view of the shaft 22 connecting the linkage 14 to the bushing 16 .
[0033] As best shown in FIGS. 2-4 , the bushing 16 includes a first end connected to the linkage 14 and a second end housing a magnet 26 . In accordance with an aspect, the bushing 16 is preferably configured as a flanged bushing with a flange member 28 and a stem 30 extending from the flange member. The stem 30 is preferably configured as an elongated cylindrical member. The flange member 28 has a diameter larger than that of the stem 30 . As previously discussed, the flange member 28 at the first end of the bushing 16 can include a slot 24 for receiving the angular end of the shaft 22 in order to connect the proximal end of the linkage to the bushing 16 . Alternatively, the slot 24 and the angular end of the shaft 22 can be configured with any other shape suitable for its intended purpose, such as a shaft having a longitudinal cross section of a square, triangle, and the like. In accordance with another aspect, the linkage 14 and the bushing 16 can alternatively be connected with suitable fasteners, e.g. pins, screws, bolts, and the like.
[0034] In accordance with an aspect, the second end of the bushing 16 includes a cavity 25 for housing a magnet 26 of a non-contact magnetic sensor, as further discussed below. As shown in FIG. 4 , the cavity 25 about a second end of the bushing 16 is preferably shaped to correspondingly receive and fixedly hold the magnet 26 . Specifically, the magnet 26 is fixedly mounted to the bushing 16 allowing it to rotate as the bushing rotates. As further discussed below, the rotational movement of the magnet 26 with respect to the sensor 20 results in an output signal representative of a positional relationship between the header and the ground.
[0035] As best shown in FIGS. 6-8 , the mount 18 includes a body 32 and spaced apart first and second rotational stops 34 , 36 . Preferably, the mount 18 is configured as a block for operatively connecting to a flexible cutter bar system. As further discussed below, the block can be appropriately modified such that the control sensor assembly 12 is applicable to different types of headers, e.g., corn header, auger, draper and the like.
[0036] The body 32 includes a counterbore 38 and a through hole 40 extending through the counterbore 38 . The through hole 40 extends from a first surface 42 of the body to a second surface 44 of the body opposite the first surface and has a central longitudinal axis substantially transverse to a plane of the first surface 42 . The body further includes an anterior surface 46 adjacent the counterbore 38 and extending substantially transverse to the first surface 42 .
[0037] As shown in FIG. 6 , the through hole 40 is configured to receive the second end of the bushing 16 . As shown in FIGS. 5A and 5B , a seal 48 , e.g., an oil seal, can be coupled around the stem 30 of the bushing 16 . Specifically, the seal 48 is shaped to slidably fit around the cylindrical shape of the stem 30 of the bushing. When assembled to the mount, the seal 48 surrounds the stem 30 and sits adjacent the flange member 28 . Thus, when the through hole 40 receives the bushing 16 , the seal 48 seats within the counterbore 38 and prevents dirt and moisture from entering.
[0038] Additionally, the body is sized so as to have a longitudinal length of the through hole 40 to be greater than a longitudinal length of the stem 30 of the bushing 16 when the bushing is seated on the block. In other words, the bushing 16 is sized to have a longitudinal length such that the second end of the bushing is spaced from the second surface 44 when fully seated on the block. This way, the distal end of the bushing housing the magnet is spaced from the second surface thereby creating an air gap between the magnet and the sensor mounted to the second surface.
[0039] As shown in FIG. 7 , the through hole 40 extends to the second surface 44 of the body. The sensor 20 is mounted onto the second surface 44 . Preferably, the second surface 44 of the body comprises a recess 50 for at least partially receiving a complementary seal 52 , e.g., an O-ring, ( FIG. 4 ) for preventing dirt and moisture from entering and causing the control sensor assembly 12 to malfunction. When assembled, the seal 52 is positioned within the recess 50 as shown in FIGS. 5A and 5B . Additionally, the second surface 44 can include a pair of openings 54 for mounting the sensor 20 onto the mount 18 with suitable fasteners, e.g. pins, screws, bolts and the like.
[0040] As best shown in FIG. 6 , the first and second spaced apart rotational stops 34 , 36 extend from the first surface 42 . Each rotational stop 34 , 36 is positioned adjacent a lateral side of the counterbore 38 and the first rotational stop 34 includes an engaging surface 56 at an angle α of about 80 to 100 degrees relative to an engaging surface 58 of the second rotational stop 36 . Of course, the rotational stops can alternatively be configured with an angle α more or less than 80 to 100 degrees or any angle between 80 and 100 degrees. The first rotational stop 34 and second rotational stop 36 are respectively spaced from each other about the first surface 42 of the mount 18 .
[0041] The engaging surfaces 56 , 58 of the respective first and second rotational stops 34 , 36 define a space or range of motion the linkage 14 can pivot relative the mount 18 . While the first and second rotational stops 34 , 36 are referred to as rotational stops, they do not necessarily have to, but can, function as rotational stops. Instead, the first and second rotational stops 34 , 36 can be guide surfaces collectively forming a one way guide slot to aid in properly assembling the linkage 14 to the mount 18 in a proper orientation. In other words, the first and second rotational stops 34 , 36 collectively form a guide slot having a posterior back wall and a tapered opening about its anterior end. The guide slot is preferably configured to have a posterior end complementary in shape to receive the bushing 16 and an open anterior end through which the linkage 14 will reside in with enough play so that the inner side walls of the guide slot do not engage the linkage 14 during general operation.
[0042] The through hole 40 has a diameter slightly larger than the diameter of the stem 30 of the bushing 16 such that the bushing 16 is rotatable therein. As the bushing 16 rotates, the linkage 14 connected to the second end of the bushing 16 rotates. The linkage 14 has a limited range of motion as defined by its connections with the header height control system and is generally restricted to movement between the first and second rotational stops 34 , 36 .
[0043] As shown in FIG. 6 , the mount 18 includes a curved section 60 extending between the first and second rotational stops 34 , 36 . The curved section 60 is sized and configured to receive the flange member 28 of the bushing 16 . Specifically, it is shaped to be complementary to the shape of the flange member 28 of the bushing 16 .
[0044] The rotational stops 34 , 36 each have a mounting surface 62 substantially parallel to and spaced from the first surface 42 for engaging with the header and an opening 64 through which a fastener is passable for securing the mount 18 to the frame of a header. The mount 18 can be connected to the frame 10 with any suitable fasteners, e.g. pins, screws, bolts and the like. Alternatively, the mount 18 and the type of fasteners used can be adjusted to accommodate different headers, e.g., a corn header, draper, auger and the like.
[0045] When fully assembled and attached to the header, the mounting surface 62 of the rotational stops 34 , 36 directly engages the frame 10 and the linkage 14 is positioned completely between the first and second rotational stops 34 , 36 . The proximal end of the linkage 14 is also positioned completely between the mounting surface 62 of the first surface 42 .
[0046] Referring to FIGS. 6 and 7 , the mount 18 further includes lateral side surfaces 66 extending substantially transverse to the first surface 42 . Further, each of the first and second rotational stops 34 , 36 include lateral side surfaces substantially parallel to and in line with respective lateral side surfaces 66 of the body.
[0047] Referring back to FIGS. 2-4 , the sensor 20 is mounted to the mount 18 and spaced from the second end of the bushing 16 . As discussed above, the second surface 44 of the body of the mount 18 contains a pair of openings 54 for mounting the sensor 20 onto the mount 18 .
[0048] The sensor 20 is preferably a non-contact magnetic sensor, such as a Hall effect sensor. In order to properly function, the control sensor assembly 12 needs to properly maintain the air gap between the sensor 20 and the magnet 26 . This air gap formed between the sensor 20 and the magnet 26 , as a result of the bushing 16 having a longitudinal length sized less than a longitudinal length of the through hole 40 , allows for proper functionality of the non-contact magnetic sensor. Unlike currently used sensors, the sensor 20 disclosed in the subject application does not have connected moving parts. Thus, the sensor 20 disclosed in the subject application does not result in wear that can result in damage to the sensor.
[0049] As shown in FIG. 2 , the control sensor assembly 12 can be fully assembled prior to installation to the frame 10 . As previously discussed, the through hole 40 on the mount 18 extends between the first surface 42 and the second surface 44 . When fully assembled, the stem 30 of the bushing 16 is received within the through hole 40 about the first surface 42 . The proximal end of the linkage 14 is connected to the flange member 28 of the bushing 16 . The sensor 20 is mounted about the second surface 44 of the mount 18 such that the magnet 26 on the bushing 16 is spaced from the sensor 20 defining an air gap therebetween. When fully assembled, the control sensor assembly 12 is secured to the frame 10 of the header. As previously discussed, the rotational stops 34 , 36 (or guide slot) assist in proper placement of the mount 18 when securing the mount onto the frame 10 .
[0050] Referring now to FIG. 10 , there is shown a side view of a frame 10 of a header. When fully assembled and installed onto the frame 10 , the control sensor assembly 12 (not shown) is connected to the header height control system 11 . Specifically, the linkage 14 connects the control sensor assembly 12 to the header height control system 11 . During harvesting operations, the header of the agricultural harvester travels along the field. As the header travels across the field, the cutter bar assembly 76 moves up and down causing the sensor arm 68 to move up and down. The sensor arm 68 is configured to rest on the cutter bar assembly 76 . The sensor arm 68 is also welded to a sensor rod 70 . Thus, when the sensor arm moves up or down, the sensor rod 70 rotates as well. The rotation of the sensor rod 70 causes a linking member 72 to rotate accordingly. Further, the linking member 72 is coupled to the linkage 14 of the control sensor assembly 12 by a connector 74 . As a result, the rotational motion of the linking member causes the linkage 14 to rotate.
[0051] When the linkage 14 of the control sensor assembly 12 ( FIG. 2 ) rotates, the bushing 16 and the magnet 26 rotate. Specifically, the magnet 26 is fixedly mounted to the bushing 16 allowing it to rotate as the bushing rotates. The rotation of the magnet results in the sensor 20 outputting a signal representative of a positional relationship between the header and the ground. Specifically, the sensor 20 configured as a Hall effect sensor produces a voltage representative of the positional relationship between the header and the ground.
[0052] In sum, when the cutter bar assembly 76 moves up or down, the header height control system 11 and its components discussed above cause movement of the linkage 14 and magnet 26 of the control sensor assembly 12 . When the magnet 26 rotates, the sensor 20 produces an output voltage representative of the positional relationship between the header and the ground. The output voltage is transmitted to a computer of the agricultural harvester.
[0053] Although the frame 10 as shown in FIG. 1 is configured to have two sensor assemblies spaced along a side end of the frame, additional sensor assemblies can be placed at additional locations along the width of the header. For example, a draper header can have four control sensor assemblies, two for tilt and two for height. Additionally, an auger head can have four control sensor assemblies, while a corn header can have between two and four or more control sensor assemblies.
[0054] While the subject application has been described with reference to several aspects, it will be appreciated by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the subject application. In addition, modifications may be made to adapt a particular situation or material to the teachings of the subject application without departing from the essential scope thereof. It is to be understood, therefore, that the subject application not be limited to the particular aspects disclosed, but it is intended to cover modifications within the spirit and scope of the subject application as defined by the appended claims. | A control sensor assembly for an agricultural harvester is provided. The control sensor assembly includes a linkage for connection to a header height control system, a bushing, a mount and a sensor mounted to the mount. The bushing includes a first end connected to the linkage and a second end housing a magnet. The mount includes a body having a through hole extending from a first surface to a second surface opposite the first surface for receiving the bushing and a first rotational stop about the first surface and adjacent the through hole. The sensor is spaced from the second end of the bushing. The control sensor assembly according to the subject application is designed to provide an improved mount for the control sensor assembly that utilizes a single mount to perform multiple functions. | 6 |
TECHNICAL FIELD
This invention relates to sanitary plastic piping for the food processing industry and, more particularly, to apparatus and methods for more conveniently fabricating on-site plastic pipe fittings which will meet sanitarian standards.
BACKGROUND OF THE INVENTION
Sanitary piping as used in the food processing industry is primarily characterized by the requirement for corrosion resistance and stream-line fluid flow free of crevices and traps into which particulate matter that may be carried by the fluid stream might accumulate. To fill this need, the food and beverage industry makes extensive use of smooth bore sanitary piping that is almost exclusively made of stainless steel, monel or other corrosion resistant metallic alloys. These piping installations normally include a number of quick-connect/disconnect fittings to permit critical sections of the pipe to be dismantled for periodic cleaning, replacement, or inspection so that the sanitary integrity of the food processing system can be maintained.
Although stainless steel and monel pipes are usually thought to be corrosion resistant, problems have been encountered when brine and various acids are significant constituents of the fluid carried by the piping system. Certain foods such as catsup and bar-b-que sauce and those having a garlic content are also known to be troublesome. The corrosion problem is further aggravated by the periodic need to use clean-in-place solutions to remove possible pockets of accumulated organic matter. Through the combined effects of reactive food materials and such cleaning solutions, replacement of corrosion resistant piping is an on-going periodic activity.
Of course, there are several plastic materials which offer better corrosion resistance than metallic alloy pipes and which being transparent would permit in-place interior inspection without disassembly. Further, the use of plastic piping which permits the use of microwave heating of the fluid stream would permit different and more advanced methods of food processing to be employed.
The introduction of plastic pipe sections into the food processing industry has heretofore been inhibited by several factors. Sanitarians have not approved the use of solvents to glue together pipe sections in the manner commonly utilized to install ordinary household and industrial plumbing. The strict prohibitions against crevices and traps into which particulate matter carried in the fluid stream rule out the use of conventional plastic fittings. While it is conceivable that plastic fittings having the appropriate internal contours to satisfy sanitary flow requirements could be fabricated in analogous fashion to the presently available metal fittings, there are no known welding techniques avaliable for attaching such plastic fittings. The fatory casting of sanitary flow end-connections on pipe lengths also does not seem to be feasible in view of the myraid lengths and shapes of pipe runs to be supplied in practice. Accordingly, while it would appear to be extremely advantageous to employ plastic piping in sanitary-flow installations, there has not yet been devised a practical method for permitting appropriate piping connections to be made in the field.
SUMMARY OF THE INVENTION
In accordance with the principles of the present invention, we have devised a portable apparatus, suitable for table or work bench mounting, which facilitates the on-site, field fabrication of sanitary flow plastic pipe connections. This apparatus makes advantageous use in the field of certain properties exhibited by plastic pipe which has been factory extruded. In the normal fabrication of extruded plastic pipe, the extruder exit die diameter is usually larger than the final pipe diameter by an amount determined by the "draw down" through the sizing die. In being pulled through the dies, the pipe partially cools and certain stresses are locked-in. It has been discovered that, by controllably reheating a predetermined length of the end of the plastic pipe, the stresses that were induced in the skin of the pipe during its original extrusion may be relieved to produce self-flaring of the pipe end wall between its inner and outer diameter "skin" surfaces. This self-flaring is believed to be occasioned by the different stresses locked into the two skin surfaces so that when the stresses are relieved, the two surfaces bend to different radii. By limiting the longitudinal extent of reheat, the expanded end-wall may be subjected to embossing and forming dies to produce the contours of a sanitary flow pipe connection analogous to those exhibited by corresponding metallic pipe connections.
In the illustrative embodiment, the selective reheating for producing the expanded end-wall and the predetermined degree of longitudinal softening is conveniently achieved through the use of a special oven, insulated clamp and heat sink arrangement located at one station of a portable work table apparatus. A snap-on depth collar is first placed on the plastic pipe to be reformed so as to admit a predetermined longitudinal length of the pipe end to the first station. The pipe is then inserted into the heat sink block which comprises two split sections. The first section includes a massive, highly thermally conductive aluminum body plate having a split aperature dimensioned to intimately embrace the outer diameter of the pipe. The section is dimensioned similarly to the first section but is of an insulating material such as "Marinite". The depth collar and thickness of the heat sink are proportioned so that with the pipe end inserted through the heat sink until the collar contacts the aluminum plate, a sufficient length of the pipe end protrudes through the insulating plate of the heat sink block to be admitted to the oven. After being admitted to the oven for a sufficient time, the pipe and attached heat sink is transferred to the flange-forming station of the work table and clamped. A die having the appropriate contours to emboss the expanded end-wall is then advanced to meet and suitably form the exposed pipe end. Advantageously, these contours include a semi-annular ring to form an O-ring recess in the pipe flange analogous to the conventional quick-connect metallic pipe fittings used in sanitary flow piping. The end section thus formed on the plastic pipe is such that the plastic section is fully interchangeable with metallic sanitary piping.
It is to be noted that unlike prior art arrangements for post forming plastic pipe ends, the apparatus of the invention controls the reheating and forming to preserve the dimensions and surface integrity of the pipe's inner diameter. Accordingly, sanitary flow geometry is maintained not only throughout the length of the pipe, but also in the vicinity of the pipe connection. In such an integrally formed connection, there are no pockets in which particulate matter could accumulate. In the illustrative embodiment, even heating about the circumference of the pipe end is facilitated by the special oven which includes a fan to overcome temperature differentials which would otherwise arise from the natural convection of the air being heated in the oven space.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects and features of the invention are described in detail in the ensuing specification and drawings in which:
FIG. 1 shows an enlarged cross-sectional view of a hypothetical plastic pipe joint illustrating two different types of flange couplings and demonstrating the problems which can arise when non-integral fittings are employed.
FIG. 2 shows a partial sectional view of a controllably reheated end portion of a length of plastic pipe positioned in the heat sink block prior to embossing;
FIG. 3 shows a top view of the portable plastic pipe forming apparatus of the illustrative embodiment;
FIGS. 4 and 5 show a partial sectional side and an end view of the heat sink block and clamp assembly;
FIG. 6 shows a partial sectional view of the oven and fan assembly;
FIG. 7 shows a partial sectional view of the ram and die assembly of the illustrative embodiment; and
FIG. 8 shows an alternative heat sink block assembly clamped to a length of plastic pipe so as to eliminate the need for a separate depth collar.
DETAILED DESCRIPTION
In FIG. 1, an attempt has been made to depict how two lengths of extruded plastic pipe, 10 and 11, might be coupled together by following, in plastic, techniques similar to those employed when joining lengths of metallic piping. Pipe 10 has affixed thereto a plastic flanged ferrule 12, and pipe 11 has affixed thereto a somewhat different plastic ferrule 13, each ferrule having a hypothetical design based on a comparable metallic fitting known in the art. The two flanges are urged together by conventional steel clamp 17. The inner circumference 14 of ferrule 13 is tapered to make a tight frictional engagement with the outer circumference 15 of pipe 11. Whatever glue or adhesive is required to be used between 14 and 15 to assure a firm bonding and fluid sealing of ferrule 13 to pipe 11 has not been shown. Because of unavoidable differences in production dimensional tolerances, the end 11a of pipe 11 will usually find itself positioned a somewhat variable and indeterminate distance g behind the parting face 13f of ferrule 13. Accordingly, an annular "pocket" of length g and having a depth determined by the wall thickness of pipe 11 may be left into which particulate matter carried by the fluid stream transported by the piping system may accumulate.
The annular gap may, of course, be obviated by making the taper of inner circumference 14 shallower than that shown, but this may allow the end 11a of pipe 11 to project beyond parting face 13f, requiring the excess to be machined off. While this manner of construction might avoid the creation of an annular pocket 15, the machining operation is a definite inconvenience.
A further alternative type of attachable flange arrangement is shown on pipe 10 which uses a plastic flange 12 that is provided with an internal lip 18 which meets the end 10a of pipe 10 to somewhat more accurately locate pipe end 10a with respect to parting face 12f of flange 12 than was possible between pipe end 11a and parting face 13f. However, the accuracy of the result depends on a smooth, right-angle cut off of pipe 10. Furthermore, the secure bonding ferrule 12 to pipe 10 must depend on the use of some hypothetical glue or adhesive which would be sufficiently strong and non-toxic and be free of solvent residue and thereby qualify for sanitarian approval. Whereas metallic pipes may be rather accurately and non-corrosively butt-welded or swaged together and metallic flanged ferrules butt-welded or swaged to metallic pipe sections in such a manner as to produce smooth interior bores, no such techniques are available for attaching plastic flanges to plastic pipe. We have discovered, however, that it is not necessary to attach flanges at all and that suitable flanges may be produced on the job site out of ordinary pipe sections.
FIG. 2 is a partial cross-sectional view of the end of a conventionally extruded plastic pipe 21 that has been positioned in the heat sink block 25 of the illustrative embodiment and controllably reheated in the oven (FIG. 6) of the illustrative embodiment. The reheating has relieved the draw-down stresses that were locked into the pipe during its original extrusion from the exit die (not shown) of the extrusion machine (also not shown, but well-known). Prior to being heated, a snap ring depth gage collar 27 is attached to plastic pipe 21 at a longitudinal distance "l"+h from the pipe end. Referring now to FIG. 4, the pipe 21 is inserted into heat sink block 25 until collar 27 makes contact with the heat sink block. An axial length "l" (FIG. 2) then protrudes beyond the opposite surface of heat sink 25. The length "l" of pipe 22 will then be exposed to the heat of oven 60 (see assembly view, FIG. 3) but the heat sink 25 will limit longitudinal heat penetration. The limitation of the reheating and stress-relieving to the axial length l produces a different degree of bending in the outer pipe skin 22 than in the inner pipe skin 23. This different degree of bending causes the end wall to become flared to a thickness w' which exceeds the normal, cool wall thickness w of the unheated pipe. Limiting of heat penetration is important to the forming of a sanitary flow coupling. Enough heat must be applied to the end wall to provide the flared width w' uniformly about the pipe circumference wiithout allowing so much of the axial length of pipe 22 to become softened that the inner skin 23 becomes wavy.
To limit the longitudinal heat penetration to the axial length "l", heat sink block 25 conprises a pair of high thermal conductivity body portions 25a, 25a' fabricated advantageously of aluminum which are clamped together under the urging of clamping screw 41, FIG. 4, to intimately embrace the outer circumference of pipe 22. The front face of block 25, which will face oven 60, is relieved for a considerable portion of its overall axial depth h to accomodate a split heat shield 25b, 25b' advantageously fabricated of Marinite or similar material. Heat shield 25b, 25b' insulates the aluminum bodies 25a, 25a' against direct radiant heating by oven 60 when the pipe length "l" is introduced into the oven cavity 66.
FIG. 8 shows an alternative heat sink block device which eliminates the need for a separate depth collar 27. The split halves of the heat sink are hingeably attached to one another by hinge 87 and quick connect cam and hasp assembly 88. The inner metallic portions 85a and 85a' correspond to inner metallic portions 25a and 25a' of FIGS. 2, 4 and 5 while the thermal insulating portions 85b and 85b' correspond generally to thermal insulating portions 25b and 25b' of FIGS. 2, 4 and 5. In addition, however, an outer circular strap member 85c-85c' has been provided to which hinge 87 and cam and hasp assembly 88 are affixed. A pair of secant-like grooves 89-89' have been cut through the perimeter of heat sink 85 to permit engagement with posts 43, FIG. 5 of the heating work station 33, FIG. 3; thus accurately and conveniently positioning the pipe end therein.
Referring to FIG. 3, there is shown a top assembly view of the portable apparatus comprising the illustrative embodiment. A portable metallic work table 31 includes three detachable support legs 32 and two work stations 33 and 34. The first work station 33 includes the heat sink block 25 together with a clamp assembly 41 (shown in greater detail in the cross-sectional view of FIG. 4 and end view FIG. 5) and a slideably mounted oven 60, 61 and fan motor 62 (shown in greater detail in cross-sectional view FIG. 6) and slide bar 63 assembly. The second work station includes clamp 71 and female die 72 assembly and male die 84 and ram assembly 86 (shown in greater detail in the cross-sectional view FIG. 7).
In operation, a switch (not shown) is closed and thermostatically controlled electric current is supplied to the cartridge heaters 63, FIG. 6, of oven 60 and to the fan motor 62 to preheat the oven. The snap ring depth gauge collar 27 is placed on pipe 21, as shown in FIG. 2, to allow a suitable length "l" of plastic pipe to protrude through heat sink block 25. Clamp 41, FIG. 4, is then made up so that its aluminum thermally conductive halves intimately embrace the outer circumference of pipe 21.
Handle 61a is then grasped and the oven door slide 61 is lifted vertically (perpendicular to the plane of FIG. 3) exposing the cylindrical inner cavity 66 (see FIG. 6) of oven 60 facing heat sink 25. Oven door slide 61 is advantageously fabricated of "Marinite" or other heat insulating material. While its use is not critical to the operation of the invention, oven door slide 61 conserves oven heat and reduces energy expenditure.
Slide bar 65 is then manually thrust to the right (clockwise) about pivot 64 causing oven 60 and fan motor 62 to traverse leftwards along ways 68 toward heat sink 25 and clamp 41 until tab 66 contacts limit stop 65. The inner diameter of oven cavity 66 is at least 30 to 50% larger than the maximum diameter b (FIG. 2) of pipe to be heated. Fan 62f, located within oven cavity 66, is turned by motor 62 to evenly distribute the air being heated within cavity 66 thereby overcoming the tendency of the heated air to accumulate in the upper portion of the oven cavity.
When pipe end 21 has been heated for a suitable length of time, clamp 41 is loosened separating the halves 25a, 25a' and 25b, 25b' of the heat sink block 25. Pipe 21 is removed from the heat sink and transferred to work station 34 and inserted into clamp and female die assembly 71, 72. Advantageously, the depth collar 27 also serves to axially correctly position pipe 21 in die 72 prior to the tightening of clamp 71. When clamp 71 is made up to secure pipe 21, ram and die assembly 84, 86 is actuated causing ram 86 to drive male die 84 in such a manner that die ring 85 (FIG. 7) embosses the flared width w' (FIG. 2) with the hemitoroidal groove 12g (see FIG. 1) so the parting face 12f may receive a conventional sanitary flow O-ring seal. Advantageously, the contours of the female die 72 also emboss the external surface 22 of pipe 12 with the flange contour 19 (FIG. 1) of the type conventionally used with flanged sanitary steel piping. Accordingly, the flange member 12 has been formed integrally with and of pipe 10 in such a manner that there is no annular gap or crevice into which particulate matter may accumulate.
For example, the controlled heating of a 9/16 inch length l of polypropylene pipe having a cold outer diameter b of 2.125 inches and a cold inner diameter a of 1.875 inches (cold wall thickness, w, of 0.125 inches) produces a bending angle θ of 30° of the inner pipe skin 23 and a bending angle θ 2 of 45° of the outer pipe skin 22. In this example, a maximum outer diameter md at the flared-end of the pipe was 2.34 inches, the axial depth h of the heat sink block 25 was approximately 2 inches and the Marinite heat shield 25b had an axial depth of approximately 1 inch. | A portable apparatus for reforming plastic pipe ends is disclosed. The apparatus includes a heat sink clamp and depth collar for locating said clamp a predetermined distance from the end of the plastic pipe end. This heat sink clamp substantially limits axial heat penetration from an oven into the plastic pipe so as to permit the reshaping of the pipe end into a sanitary flow end, i.e. an end having imperfection-free contours. | 1 |
[0001] This is a non-provisional application claiming priority to provisional patent application No. 60/974,195 filed on Sep. 21, 2007.
FIELD OF THE INVENTION
[0002] The present invention is a method of training a living body of a patient to attribute sounds corresponded with allergens to ultimately cease negative reactions to such allergens or substances. In addition, the method of the present invention serves to identify a patient's allergies by using sound as opposed to exposing the patient to the actual substances.
BACKGROUND OF THE PRESENT INVENTION
[0003] Allergies and sensitivities are the result of the immune system reacting inappropriately to harmless, naturally occurring substances, which can affect virtually every part of the body. This bodily reaction is abnormal. The effects of allergies can range from mild symptoms to extremely harmful reactions. Sensitivities are another abnormal set of reactions. Although they have symptoms similar to those of allergies, sensitivities do not involve the immune system.
[0004] It has been observed that exposure to minute amounts of an allergic or reactive substance to the surface of the skin causes a body's muscles to immediately become weakened due to contact with the specific substance. Although no other reactions may occur from this minimal, external exposure, it has been observed that weakened muscle strength is a universal physiological response to exposure to any allergic or reactive substance. The inventor concluded that the body is recognizing the substance as “information” and the response depends on the interpretation of the information. If the body perceives the substance as harmful, it will cause an immediate physiological response. If the body perceives the substance as benign, no physiological change occurs.
[0005] The present invention takes advantage of this phenomenon, and takes it to the next degree. According to the science of biosemiotics and information theory, signals or information can be read at the molecular level in all living systems. Human physiology operates entirely on signals of information. In the case of allergies and sensitivities, the body is in error, or is incorrect in its perception of a substance. By exposing the person to the substance while simultaneously introducing a positive stimulus, the body associates the positive stimulus with the benign substance and alters its perception, interpreting the substance as beneficial.
[0006] The inventor has found that if a digital sample of the substance is transmitted to the surface of the skin, the body responds in a similar or identical fashion as if they were exposed to the actual substance. It has also been found that this bodily reaction is controlled at the subconscious level, and as such, the sound does not have to be within the range of normal human hearing capacity. The digital signal is initially created from a textual representation, including a specific sequence of words that allows for a more specific representation of the substance. This textual representation is converted to an audio signal, which has then been converted to a specific tone that represents the substance. The inaudible tone is transmitted to surface of the skin through a wrist cuff.
SUMMARY OF THE PRESENT INVENTION
[0007] The method of the present invention is as follows: While an inaudible sound, which represents the substance the body is inappropriately reacting to, is transmitted to the body, acupuncture points are pressed evenly down both sides of the spine on the Bladder Meridian, as known in Traditional Chinese Medicine. These points are utilized to temporarily strengthen all of the major organ systems. The combination of the subconscious bodily reaction to the inaudible sound and the acupressure along the spine teaches the body to not react to that particular substance or “information”. The concept that the body as a whole, not just the immune system, perceives an allergen as a threat and overreacts is the basis of the present invention.
[0008] It is the same phenomenon with sensitivities; only allergies must involve the immune system to be officially called allergies. This association causes the body to perceive the substance as a benefit, instead of as a threat. It is not unlike allergy shots, where the goal is to slowly train the body to accept highly diluted amounts of the allergen. Over time, the body is trained to accept the substance. The present invention introduces the exposure along with the positive stimulus, which allows a much faster process of accepting the substance and a resolution to the allergic reactions.
[0009] The therapeutic stimulation used in conjunction with the transmission of digital signals is the mechanism of action in training the body to accept a harmless substance. The transmission of digital signals has no effect or therapeutic value to the body. It is only the acupressure stimulation in conjunction with exposure to the digital representation that allows for a resolve in the physiological error.
[0010] The inventor has discovered that the success of the therapy depends on the accuracy of the information transmitted to the body. Therefore, a database is used to include a large number of substances and further breaks the substances down into components and further into components of the components down to the actual protein molecule. This methodology allows for superior precision in biological communication.
[0011] Provided herein as part of this application is a compendium of many of the substances and some of the elements thereof, to which people can react as allergens, the software which physicians may use in order to find that particular allergen, and a schematic for the cuff, which wraps around the patient's arm and is connected to the computer system which transmits the inaudible sounds.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a flow chart detailing the steps of the preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0013] The present invention is a method that serves to find inaudible sounds associated with a specific allergen and/or sensitivity in order to ultimately train the body's natural physiology to accept such specific protein or irritant that initially caused the allergic or sensitivity reaction. For example, a database of the present invention may house the inaudible sounds associated with cat hair. The patient would hold his or her arm in a certain way as various inaudible sounds associated with cat hair allergies are transmitted to the surface of the skin The patient will not be able to maintain the arm position and the muscle will weaken in reaction to the negative effect of the inaudible sound representative of the specific allergen. In this manner, it will become known through the database which overall allergen is the problem, as well as which inaudible sound associated with such an allergen or irritant. So, in this example, cat hair can be singled out as an irritant or allergen.
[0014] Once the negative influence on the body is determined based on the muscle response, different inaudible sounds are projected to hone in on the more specific cause of the irritation. Each of these different inaudible sounds is associated with different proteins or other sub-levels of the allergen. In the cat hair example, this would mean individual proteins within the cat hair will be probed via the different inaudible sounds. Such proteins include items as saliva, dander, etc. In other words, the different inaudible sounds seek muscular reaction to determine which part of the broader-known allergen or irritant is affecting the patient. The determination will be made when the muscle reacts to the targeted projection of the different inaudible sound.
[0015] Acupressure is then applied to certain points on the body. In the preferred embodiment, acupuncture points are pressed evenly down both sides of the spine on the Bladder Meridian. These points are utilized to temporarily strengthen all of the major organ systems. Meanwhile, the different inaudible sound specific to the distinct substance found to cause the irritation is transmitted onto the body. The combination of the subconscious bodily reaction to the inaudible sound and the acupressure along the spine teaches the body to not react to that particular substance or “information”. In other words, the different inaudible sound that represents an allergen or irritant transmitted at the same time as stimulating positive pressure points on the body ultimately trains the body to associate the allergen or irritant with positive benefit of the stimulation.
[0016] As we see in FIG. 1 , the present invention can proceed as follows. First, a speaker is positioned in the proximity of the patient ( 10 ). It should be noted that the patient also might be referred to as person. In one embodiment, the speaker may be placed on the underside of a wristband. The wristband would then be wrapped around the wrist, leg, or otherwise around an extremity of the patient. The speaker would be facing the body of the patient. Then, a sound is transmitted toward the body of the patient ( 20 ). The sound being transmitted is representative of what the actual potential allergen or reactive substance is purported to be. This means that the sound literally can be a grouping of words identifying the purported allergen. The sound being transmitted, however, will be unintelligible to the patient. This is because in the preferred embodiment, the sound is converted into a digital format ( 30 ) so as to be emitted in a digital format ( 40 ). An additional embodiment permits the sound to be encrypted ( 50 ) via conventional means. Regardless, the sound being transmitted comes out unintelligible to the patient as the conventional representative words are either inaudibly below or above the frequency for hearing ability of a human, or garbled via digital and encryption avenues. While the sound is transmitted toward the body of the patient ( 20 ), the muscle strength of the patient is monitored ( 60 ). The monitoring of the muscle strength also includes testing such as resistance force. The muscle strength of the patient will remain optimal while sounds are transmitted. However, once a sound representing an allergen or irritant prevalent with the patient reaches the body of the patient ( 70 ), the patient's muscle strength will noticeably decrease ( 80 ). The loss of muscle strength will be recorded ( 90 ) in conjunction with the certain sound. That certain sound will identify the particular allergen that caused the loss of muscle strength ( 100 ). Once the sound representing a particularly relevant allergen or irritant is identified and matched, the sound is again transmitted toward the body of the patient ( 110 ) in much the same manner as the previous times. But this time, pressure points on the patient's body via conventional acupressure are pressed while the sound representing the identified allergen is transmitted ( 120 ). This has the effect of teaching the patient's body to attribute the allergen or irritation as a physical positive, which in turn will diminish the veracity of the allergen's effect on the patient's body.
[0017] The preferred embodiment of the present invention is a method of training a living body of a patient, comprising positioning a speaker in the proximity of the patient, transmitting a series of sounds from the speaker toward the body of the patient, each sound of the series of sounds matched with a corresponding allergen, monitoring and testing muscle strength of the patient, and recording the corresponding allergen matched with each sound of the series of sounds that causes muscle strength to decrease. In addition, the present invention entails transmitting toward the body of the patient each sound of the series of sounds that causes muscle strength to decrease and pressing pressure points via acupressure while each sound of the series of sounds that causes muscle strength to decrease is further transmitted.
[0018] Moreover, facing the speaker toward the body of the patient is part of the preferred embodiment, along with converting each sound of the series of sounds into a digital format and encrypting each sound of the series of sounds. Storing and matching each sound of the series of sounds with the corresponding allergen in a database also is envisioned. An alternative embodiment involves placing the speaker onto a band, the band configured to secure to an extremity of the patient. Each sound of the series of sounds also may be converted into an unintelligible format. | A method for training a living body of a patient to attribute sounds corresponded with allergens to ultimately cease negative reactions to such allergens or substances. In addition, a patient's allergies are identified by using sound as opposed to exposing the patient to the actual substances. Acupressure is used in conjunction with the sounds to train the body to react positively to the allergens without actual allergen substance being exposed to the patient. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to apparatus and a process for the removal of insoluble substances from a liquid, and more particularly, to the purification of a liquid by the gas flotation of insoluble dispersed materials from the liquid.
2. General Background
Many industrial processes such as mining and oil recovery operations involve the treatment or handling of a liquid which contains contaminates such as fine suspended solid particles or globules of oil or other liquid substances which are immiscible in the liquid. Often, these contaminants must be removed prior to subsequent use or disposal of the liquid. For example, contaminants picked up in water used in the beneficiation of minerals must be removed from the water prior to its reuse or disposal. Similarly, water used in oil operations such as secondary recovery usually contains dispersed oil droplets which must be removed from the water prior to its reuse in the oil recovery operations or prior to its return to the environment.
Many systems have been devised for the removal of the above-described contaminants from liquids. For example, insoluble contaminants are often removed from liquids in large settling basins. This treatment is generally ineffective for the removal of finely suspended solids or insoluble liquid droplets. Other purification methods are based on filtration, but the high cost of purchasing and maintaining filtration equipment militates against the use of these techniques in most industrial operations. One of the most commonly used methods for the purification of liquids containing solids or immiscible liquids is gas flotation. Gas flotation involves the use of very small gas bubbles to agglomerate or coalesce the contaminant particles and float them to the surface of the liquid where they are separated from the liquid. The present invention employs an improved gas flotation method for the removal of suspended contaminants from liquids.
Prior Art
Several patent and literature references describe processes and equipment for the gas flotation purification of liquids. U.S. Pat. No. 2,766,203 discloses gas flotation water purification equipment comprised of several cells which are separated by foraminate baffles which permit the water being treated to pass from one cell to the next. Oil rising to the surface is removed with mechanical skimmers. U.S. Pat. No. 4,226,706 discloses air flotation apparatus comprised of a horizontal series of cells separated by solid walls. Water passing from one cell to the next must move downwardly to an opening near the bottom of the walls separating the cells. U.S. Pat. No. 3,784,468 discloses apparatus for separating liquids of different densities by gas flotation comprised of a series of flotation cells. The liquid being treated is pumped from the bottom of one cell to a liquid-gas cyclone and then into the next cell and the lighter liquid spills over a weir located at the top of the cells. U.S. Pat. No. 4,564,457 discloses an air flotation apparatus for the separation of water and oil comprised of a horizontal cylindrical vessel containing a series of aeration chambers each equipped with a gas eductor. The treated water moves beneath vertical baffles to pass from one chamber to the next. A horizontal trough for skimming oil from the liquid surface extends the length of the cylindrical vessel at the top of the vessel. U.S. Pat. No. 3,853,753 discloses an apparatus for removing dispersed oil from water comprised of a vertical cylindrical tank. The apparatus includes an upwardly inclined baffle to direct the rising water-oil mixture to one side of the cylinder. U.S. Pat. No. 3,525,437 describes gas flotation apparatus for separating solids from liquids which includes a mesh to reduce turbulence and flow speed. Other U.S. Patents which show the use of inclined baffles for directing liquid or solid flow in separation vessels are 3,769,207; 3,893,918; 4,372,757; and 4,428,841. U.S. Pat. Nos. 3,175,687 and 4,110,210 show the use of various nozzles for introducing gas-liquid mixtures into gas flotation liquid purification equipment. Other U.S. Patents which disclose gas flotation equipment and processes are 3,576,738; 3,616,919; 3,725,264; 3,849,311; 3,932,282; 4,086,160; 4,198,300; 4,251,361; and 4,399,028.
The apparatus of the present invention provides improved separation of insoluble or immiscible contaminants from a liquid relative to the operation of the abovedescribed equipment by effecting improved contact between gas bubbles and contaminants contained in the liquid being purified and by eliminating the use of mechanical skimmers for the removal of floated contaminants.
OBJECTS OF THE INVENTION
It is an object of the invention to present improved apparatus for the removal of fine suspended contaminants from a liquid. It is another object of the invention to present gas flotation equipment that more efficiently separates suspended contaminants from a liquid. It is another object of the invention to present gas flotation apparatus which provides for more efficient removal of floated contaminants from the surface of a liquid. It is another object of the invention to present gas flotation equipment which provides more efficient contact between the dispersed gas bubbles and contaminants being separated from a liquid. It is another object of the invention to present an improved process for the removal of contaminants from a liquid. It is another object of the invention to present an improved process and apparatus for the gas flotation purification of oil contaminated water. These and other objects of the invention are supported in the following description and drawings of the invention.
SUMMARY OF THE INVENTION
The improved gas flotation apparatus of the invention is comprised of an elongate vessel containing a horizontal series of gas flotation cells which are separated by partition walls which have openings to permit substantially horizontal flow of liquid passing from one cell to the next. The horizontal cells each contain a screen and two gas eductors, one located on each side of the screen. The screen serves to improve contact between the gas bubbles being emitted from the eductors and the contaminants which are suspended in the liquid being treated.
The location of the openings may be on alternate sides of the vessel in adjacent partition walls to extend the path of liquid flow through the flotation apparatus. Alternatively, the partition wall openings may all be on the same side of the vessel and the screens may have cutouts on the edges which are on the side which is opposite to the side on which the partition wal cutouts are located.
The tops of the cells are closed off by baffling which inclines in a slightly upward direction from the sidewall to an overflow weir, the baffling serving to direct contaminant-containing froth to the weir for removal of the contaminants from the flotation cells.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially cut away view in perspective of the gas flotation apparatus of the invention.
FIG. 2 is a fragmentary plan view in partial cross section taken along the line 2--2 of FIG. 1.
FIG. 3 is a fragmentary side elevation along the line 3--3 of FIG. 2.
FIG. 4 is a cross section taken along the line 4--4 of FIG. 2 illustrating the flow of liquid and gas during operation of the gas flotation apparatus of the invention.
FIG. 5 is a cross section taken along the line 5--5 of FIG. 2 illustrating the arrangement of one of the screens in the gas flotation apparatus of the invention.
FIG. 6 is an elevation of the clean liquid discharge end of the gas flotation apparatus of the invention.
FIG. 7a is a view of one form of cell partition wall useable in the gas flotation apparatus of the invention.
FIG. 7b depicts an alternate form of a cell partition wall.
FIG. 8 illustrates one embodiment of a screen which is useable in the apparatus of the invention.
FIG. 9a is an exploded fragmentary view in section showing one embodiment of the screen means of FIG. 8 in which two screens are fastened together in contiguous relationship.
FIG. 9b is an exploded fragmentary view in section showing an alternate embodiment of the screen means of FIG. 8 in which two screens are separated by spacers.
FIG. 10a is a cross sectional view of one embodiment of a gas eductor which is useable in the invention.
FIG. 10b is a cross sectional view of an alternate form of gas eductor useable in the invention.
FIG. 11 illustrates an alternate form of the inclined baffling and oil collecting trough shown in FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The gas flotation apparatus of the invention can, in general, be used to clarify a liquid by the removal of most fine suspended solids or droplets of insoluble liquids from the liquid. However, for purposes of simplification and without any intent to limit the scope of the invention, the gas flotation apparatus and process of the invention will be described with particular reference to the removal of oil contaminants from water.
Referring now to FIGS. 1-3 and 6, the gas flotation apparatus of the invention is comprised of a generally elongate vessel 1 having an inlet end wall 2 and an outlet end wall 3. Inlet end wall 2 is fitted with an oil-contaminated water inlet 4 and clean-out line 5 for flushing sand and other debris from the bottom of the gas flotation apparatus. Outlet end wall 3 is fitted with a clean water outlet 6 and a clean-out line 7. A motor-driven valve 8 which is actuated by liquid level control device 9 is attached to and controls the amount of water flowing through clean water outlet 6 to maintain the liquid level in vessel 1 between points A and B (FIG. 6). Also attached to outlet end wall 3 is a high level-low level shut-off device 10 which shuts down the gas flotation unit if the liquid level in vessel 1 rises to level C or falls to level D. Vessel 1 is also fitted with oil outlet 11 from which oil which has been separated from the water being treated is removed from vessel 1.
Internally, vessel 1 is comprised of a liquid flow region 12, which occupies the lower part of vessel 1, and a gas collection region 13, which is located above liquid flow region 12. As best seen in FIGS. 4 and 5, liquid flow region 12 and gas collection region 13 are separated by baffle means 14, which extends horizontally in a longitudinal direction from inlet end wall 2 to outlet end wall 3. Baffle means 14 sealingly engages inlet end wall 2, outlet end wall 3, and rear wall 15. In the embodiment illustrated in FIGS. 1-5, baffle means 14 consists of a flat section 16 which extends transversely in a slightly upward direction towards front wall 17 and a flange 18 which projects upwardly from the upper end of flat section 16. Oil recovery trough 19 is located along front wall 17 and is separated from liquid flow region 12 by partitions 20 and 21 which extend to and are sealingly attached to inlet end wall 2 and outlet end wall 3. Trough 19 is in communication with gas collection region 13 through its open top. Opening 22 communicates with oil outlet 11 and trough 19 and serves to permit removal of oil from trough 19. An adjustable overflow weir 23 is mounted to the top of partition 20.
Liquid flow region 12 is divided into a battery of flotation cells 24 which are separated by vertical partition walls 25. Partition walls 25 extend transversely across vessel 1 and are sealingly attached to rear wall 15, partition 20, and vessel bottom 26. Each partition wall 25 has a bottom cutout 27 to facilitate the cleaning of vessel 1. Partition walls 25 also have cutouts 28 which provide communication between adjacent flotation cells 24. Cutouts 28 are positioned and shaped to provide substantially horizontal flow of the contaminated water from one flotation cell to the next.
Each flotation cell 24 is provided with a screen means 29 which is desirably positioned vertically and transversely of vessel 1 in a plane substantially parallel to the plane of partition walls 25. In the embodiment illustrated in the drawings, the screen means divides each flotation cell into two chambers. Screen means 29 may be comprised of a single screen 30 or two or more screens 30 fastened with the flat surfaces of each screen in direct contact with each other (FIG. 9a). Alternatively, screens 30 may be separated by spacers 31 (FIG. 9b). Screens 30 may be fastened to frames 32, which impart rigidity to the screen means. When two or more screens are fastened together, the openings of adjacent screens may be aligned or they may be offset to provide a slight baffling effect. Screen means 29 may optionally have cutouts 33 to direct some of the flow of contaminated water around the edges of screen means 29. Screen means 29 are also preferably fitted with openings 34 at the lower-most point to facilitate cleaning of vessel 1.
Gas is introduced into the flotation cells by being dispersed in a stream of water supplied through conduit 35. Conduit 35 communicates with the lower portion of the liquid flow region, preferably in the vicinity of the outlet end wall 3, via tee 36 and conduit 37 which has an open end 38. Tee 36 also connects to conduit 39 which is connected to a clean water supply. Conduits 37 and 39 are fitted with shutoff valves 40 and 41 respectively. Conduit 35 is connected to the suction end of a pump 42, which discharges via conduit 43 into manifold header 44. Header 44 communicates with gas eductors 45. Gas eductors 45 in turn communicate with gas dispersion conduits 46. Gas dispersion conduits 46 have open ends which communicate with the lower portion of flotation cells 24. In the embodiment illustrated in FIGS. 1-3, two gas dispersion conduits are provided for each flotation cell, one located on each side of screen means 29, i.e., one gas dispersion conduit is located in each chamber of each cell. A baffle plate 47 may optionally be positioned near each gas dispersion conduit to further disperse gas bubbles being emitted from gas dispersion conduits 46.
As shown in FIG. 10a, gas eductors 45 have water inlets 48 removably threaded into tube 49 and gas inlet ports 50 which are open and in communication with gas regon 13. Eductor outlet 51 is connected to gas dispersion conduit 46. FIG. 10b illustrates an alternate embodiment of the gas eductor which is similar to the device illustrated in FIG. 10a except that tube 149 has a narrowed throat 52.
In operation, oil-contaminated water enters the first chamber of the first flotation cell of vessel 1 through inlet 4 and slowly moves through the cell toward screen means 29 which devices the cell into two chambers. In the first chamber, the contaminated water is continuously contacted by fine gas bubbles which enter the cell through gas dispersion inlet 46. The gas bubbles, which are finely dispersed, contact and adhere to the oil droplets in the contaminated water, thereby increasing the buoyancy of the oil droplets and causing them to rise toward the surface of the water in the cells. The water being treated enters the second chamber of the first flotation cell by passing through screen means 29 or around the screen means via cutout 33. The amount of water passing around the screen means is determined by the size of the screen openings and the size of screen cutout 33. The relative amount of water passing through cutout 33 determines the residence time in the cell. It is desirable to maintain a sufficient residence period to permit enough oil contaminant to be removed from the water in the flotation apparatus to lower the oil content to below the maximum amounts permitted under the pertinent environmental regulations. However, it is also important that the screen openings and the screen cutouts be large enough to avoid the creation of a pressure differential across the screen means. Although the screen mesh size is not critical, it is preferred that the screens used in the screen means have a mesh size of about one one-hundredth (1/100) inch to about one-fourth (1/4) inch. It should be understood that the screen cutouts are optional. They are not necessary if the residence time of the contaminated water in the flotation apparatus is sufficient to effect the desired degree of water purification. It can be appreciated that one of the functions of the screen means is to help reduce turbulence in the flotation cells. It is not known for certain, but it is believed that the screen means also helps to coalesce the oil droplets.
In the second chamber of the first flotation cell, the contaminated water is again contacted with gas bubbles, which are emitted from the second gas dispersion inlet. As the water passes through the second chamber of the first cell, it approaches the cutout in the partition wall separating the first and second flotation cells. In the embodiment in which the screen means are provided with cutouts, it is desirable that the screen cutouts and the partition wall cutouts be on opposite sides of the flotation apparatus. This will enable the contaminated water to follow a serpentine path through the apparatus and will ensure that the maximum amount of contaminated water is contacted with the dispersed gas bubbles. If the screens contain no cutouts, it is preferable that the cutouts of adjacent partition walls be located on opposite sides to avoid channeling of the water along one sidewall of the flotation apparatus. The gas-contaminated water contact process described above is repeated in the second and each subsequent flotation cell.
Partition wall cutouts 28 are designed to permit contaminated water to move from cell to cell in a substantially horizontal path. This is the preferred path of movement since it does not hinder the upward movement of the oil droplets. Cutouts 28 are of sufficient size to allow the water to pass from cell to cell without creating turbulence. Since additional water is added to the system through gas dispersion conduits 46, it may be desirable to increase the size of cutouts 28 (and, if desired, screen cutouts 33) as the distances between the flotation apparatus inlet end and the partition walls increases. In other words, the cutouts in the partition walls and screens closest to the outlet end of the apparatus may be larger than those closest to the inlet end of the apparatus.
The shapes of partition wall and screen cutouts 28 and 33 are not critical. Cutouts 28 and 33 are depicted as semicircular in FIGS. 1-5, 7a, and 8, but these cutouts can have other shapes. FIG. 7b shows an alternate embodiment of a partition wall 125 having an elongated rectangular cutout 128 along one side edge. In some installations, an elongated rectangular cutout shape may be preferable to the semicircular cutout shape since it can facilitate a more uniformly horizontal movement of the contaminated water passing from cell to cell. Cutouts 33 may also have rectangular shapes.
The gas may be introduced into the flotation cells by any suitable means. It is preferably introduced into the flotation cells in the form of a dispersion of tiny gas bubbles in relatively clean water. It is convenient to use the substantially oil-free water that has been processed in the apparatus of the invention. Water obtained from the lower part of the last flotation cell is preferred since this is the cleanest water in the flotation apparatus. When water from the gas flotation flotation apparatus is used, valve 40 is open and valve 41 is closed. If it is desired to use an alternate source of water for gas dispersion, such as fresh sea water, valve 41 is opened and valve 40 is closed. Water entering the gas dispersion system is drawn through conduit 35 by pump 42. Pump 42 may be any suitable type of pump. Pump 42 discharges water via conduit 43 into manifold header 44 which in turn feeds water to gas eductor 45. The pressure of the water entering the eductors is preferably in the range of about 25 to 75 psig.
Any type of eductor which entrains a gas into a liquid can be used in the apparatus of the invention. FIGS. 10a and 10b illustrate typical gas eductors. In the embodiment shown in FIG. 10a, water enters the eductors through eductor water inlet 48. As it passes through nozzle 53, the force of the water creates a low pressure region 54. The low pressure in region 54 causes gas to be drawn from gas collection region 13 into eductor 45 through gas inlet 50. The gas and water mix in low pressure region 54 with sufficient turbulence to form a dispersion of fine bubbles in the water. The dispersed gas is carried via conduits 46 into the flotation cells, where it mixes with the contaminated water being treated. The pressure in vessel 1 is generally atomspheric.
As the gas bubbles rise in flotation cells 24, they contact and attach themselves to the oil droplets contained in the feedwater. The oil droplets are carried to the top of the cells by the added buoyancy imparted to the droplets by the gas bubbles. The flow pattern of the gas and oil is most clearly shown in FIG. 4. As the floated oil droplets reach the top of flotation cells 24, they are forced across the top of the cell along inclined baffle 14 until they reach the open area between flange 18 and overflow weir 23. In the open area, the gas bubbles are released from the oil and return to gas region 13. The oil is guided toward overflow weir 23 by partition wall top sections 55 and screen wall top sections 56. The separated oil is forced over weir 23 and into oil recovery trough 19, from which it is removed from the flotation apparatus through outlet 22 and conduit 11. As can be appreciated, the inclined baffle 14 eliminates the need for mechanical or suction skimmers to remove oil from the flotation apparatus.
As noted above, the water level in vessel 1 is maintained between points A and B by liquid level controller 9. The water level can be adjusted to provide the most efficient operation. It is important that the water be maintained below overflow weir 23 to prevent water from being carried over into oil recovery trough 19. The water level is presented from reaching the top of weir 23 by high level-low level shut-off device 10 which shuts the unit off if the water level reaches point C. Point C is, of course, located below weir 23. Shut-off device 10 also shuts the unit down if the water level drops to point D, thereby preventing oil from flowing through clean water outlet 6.
The inclined baffle 14 can have a different arrangement from the embodiment illustrated in FIGS. 4 and 5. FIG. 11 shows one alternate inclined baffle arrangement. In this embodiment, there are two inclined baffles 113 which incline upwardly toward the center of vessel 1. Oil recovery trough 119 is located between baffles 113. Oil is pushed transversely up the lower surfaces of baffles 113 and flows into trough 119 from which it is removed from the gas flotation apparatus through conduit 111.
Any suitable gas can be used in the operation of the apparatus of the invention. Suitable gases include natural gas, nitrogen, and air. It is generally convenient and preferred to use natural gas. The gas is charged into vessel 1 through line 57, which is fitted with a stop valve 58 (FIG. 1).
For some operations, it may be preferred to inject a flocculating agent into the contaminated water entering vessel 1. Line 59, fitted with valve 60, is provided for this purpose.
Although the invention has been described with particular reference to specific embodiments, it is understood that alternate embodiments which are not illustrated are contemplated. For example, two or more screen means may be placed in each flotation cell. Also, different gas dispersion means can be used. For instance, a single gas eductor may be used to supply dispersed gas to two or more gas dispersion conduits 46. The scope of the invention is limited only by the breadth of the appended claims. | Apparatus for the dispersed gas flotation and separation of insoluble, dispersed contaminants from a liquid comprised of a horizontal series of flotation cells, separated by baffles that permit the substantially horizontal flow of liquid from one cell to the next, each cell being equipped with one or more gas dispersing nozzles and screens which aid in the coalescence and flotation of the contaminant particles, and an inclined baffle above the horizontal series of cells to urge the floated impurities toward a weir positioned to remove the impurities from the surface of the liquid. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. 119 of Danish application Ser. No. 0673/97 filed Jun. 9, 1997 and U.S. Provisional application No. 60/049,071 filed Jun. 10, 1997, the contents of which are fully incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to a new method of treating undyed fabrics, garments, or yarn comprising treating the undyed fabric, garment, or yarn in an aqueous medium with a haloperoxidase, a halide source and a hydrogen peroxide source.
BACKGROUND OF THE INVENTION
Textiles composed of materials such as wool, and in particular, cellulosics such as cotton, are frequently bleached during manufacturing. Hydrogen peroxide is often used as a bleaching agent. In addition to hydrogen peroxide, the bleaching solutions will normally contain silicates, caustic agents, chelators, organic stabilizers, magnesium salts, and wetting agents. The bleaching treatment has two primary functions; the first is to obtain a high level of whiteness, and the second (when the textile is a cellulosic material) is to break down and solubilize mote materials. Typical bleaching conditions are 0.5-1.5% hydrogen peroxide, 0.5-2% sodium silicate, 0.1-0.4% caustic, and 0.2% chelators at a temperature of 100° C. WO 92/18683 describes a process for bleaching dyed textiles with peroxidases and oxidases.
Furthermore, fabrics, garments, or yarns are sometimes treated in order to improve dyeing characteristics such as dye uptake.
Furthermore, fabrics, garments, or yarns of woll or other animal hair fibers are sometimes treated in order to protect against the tendency to shrink. Methods to generate shrink-resistant fabrics, garments, or yarns are known. The most commonly used method for wool is the IWS/CSIRO Chlorine Hercosett process, which comprises an acid chlorination of wool, followed by a polymer application. This process imparts a high degree of shrink-resistance to wool, but adversely affects the handle of wool, and generates environmentally damaging waste. Other methods to reduce shrinkage of fabrics, garments, or yarns which do not result in release of damaging substances to the environment have been described, including processes such as low-temperature plasma treatments.
SUMMARY OF THE INVENTION
The object of the present invention is to provide an enzyme-based method for treating fabrics, garments, or yarn, in order to provide advantages with regard to improved bleaching effect, dye uptake, and/or shrink-resistance, and by which methods, it is possible to reduce fiber damage and limit the use of environmentally damaging chemicals.
It has now been found that certain properties of fabrics, garments, or yarn may be improved by subjecting the undyed fabric, garment, or yarn to a treatment with a haloperoxidase together with a hydrogen peroxide source and a halide source in an amount effective for providing the desired effect.
One embodiment of the invention provides a method of manufacturing a bleached fabric, garment or yarn comprising treating undyed fabric, garment or yarn in an aqueous medium with an effective amount of a haloperoxidase, a halide source and a hydrogen peroxide source at a lower temperature typically at 30-70° C. than what is used in a traditional hydrogen peroxide bleaching. This embodiment provides a process for bleaching undyed fabric, garment or yarn at a lower temperature than 100° C., and a bleaching process which requires less chemicals than what is needed today. Another embodiment provides a method of bleaching motes in a cellulosic fabric, garment or yarn comprising treating undyed fabric, garment or yarn in an aqueous medium with an effective amount of a haloperoxidase, a halide source and a hydrogen peroxide source.
Another embodiment of the invention provides a method of manufacturing fabrics, garments, or yarns with improved shrink-resistance or dye uptake. The fabric, garment, or yarn is preferably of wool.
Other aspects of the invention will become apparent from the following detailed description and the claims.
DETAILED DESCRIPTION OF THE INVENTION
Before the methods of the invention are described, it is to be understood that this invention is not limited to the particular methods described. The terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting since the scope of the present invention will be limited only by the appended claims.
As used in this specification and the appended claims, the singular forms "a", "an", and "the" include plural references unless the context clearly dictates otherwise. Thus, for example, references to "haloperoxidase" or "haloperoxidase preparation" include mixtures of such haloperoxidase, reference to "the method" includes one or more methods, and/or steps of the type described herein and/or which will become apparent to those persons skilled in the art upon reading this disclosure and so forth.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods and materials are now described. All publications mentioned herein are incorporated herein by reference for the purpose of disclosing and describing the material for which the reference was cited in connection with.
The term "undyed" refers to fabric, garment, or yarn that has not fully completed a dyeing process. Dyeing may optionally be carried out during or after the method according to the invention. Preferably the enzyme treatment is carried out before the dyeing step.
The term "bleaching" is here defined as a whitening of the fabric, garment, or yarn, and can be measured by using the change in the color space coordinates L*a*b*(CIELAB-system): L* gives the change in white/black at a scale of from 0 to 100. A decrease in L* means an increase in black color (decrease of white color), an increase in L* means an increase in white color (a decrease in black color). Bleaching may also be measured using Stensby units (W=L+3a-3b).
Fabric can be constructed from fibres by weaving, knitting or non-woven operations. Weaving and knitting require yarn as the input whereas a non-woven fabric is the result of random bonding of fibres (paper can be thought of as non-woven).
Woven fabric is constructed by weaving "filling" or weft yarns between wrap yarns stretched in the longitudinal direction on the loom. The wrap yarns must be sized before weaving in order to lubricate and protect them from abrasion at the high speed insertion of the filling yarns during weaving. The filling yarn can be woven through the warp yarns in a "over one--under the next" fashion (plain weave) or by "over one--under two" (twill) or any other myriad of permutations. Strength, texture and pattern are related not only to the type/quality of the yarn but also the type of weave. Generally, dresses, shirts, pants, sheeting's, towels, draperies, etc. are produced from woven fabric.
Knitting is forming a fabric by joining together interlocking loops of yarn. As opposed to weaving which is constructed from two types of yarn and has many "ends", knitted fabric is produced from a single continuous strand of yarn. As with weaving, there are many different ways to loop yarn together and the final fabric properties are dependent both upon the yarn and the type of knit. Underwear, sweaters, socks, sport shirts, sweat shirts, etc. are derived from knit fabrics.
Non-woven fabrics are sheets of fabric made by bonding and/or interlocking fibres and filaments by mechanical, thermal, chemical or solvent-mediated processes. The resultant fabric can be in the form of web-like structures, laminates or films. Typical examples are disposable baby diapers, towels, wipes, surgical gowns, garments for the "environmental friendly" fashion, filter media, bedding, roofing materials, backing for two-dimensional fabrics and many others.
According to the invention, the process may be applied to any fabric known in the art (woven, knitted, or non-woven). In particular the bleaching process may be applied to cellulose-containing or cellulosic fabrics, such as cotton, viscose, rayon, ramie, linen, lyocell (e.g., Tencel, produced by Courtaulds Fibers), or mixtures thereof, or mixtures of any of these fibres, or mixtures of any of these fibres together with synthetic fibres (e.g., polyester, polyamide, nylon) or other natural fibers such as wool and silk. The term "wool" includes any commercially useful animal hair product, for example, wool from sheep, camel, rabbit, goat, or llamas, and includes wool fiber and animal hair. The method of the invention can be used with wool or animal hair material in the form of top, fiber, yarn, or woven or knitted fabric. The enzymatic treatment can also be carried out on loose flock or on garments made from wool or animal hair material.
The treatment can be performed at many different stages of processing.
The term "shrinkage" refers to the felting shrinkage of fibers as defined in IWS TM 31, i.e., felting shrinkage is the irreversible shrinkage caused by progressive entanglement of the wool fibers induced by washing in an aqueous solution, and is defined as the reduction in length and/or width induced by washing. Shrinkage can be measured in accordance with IWS TM 31, or it can be measured using the following modification. Wool samples (24 cm×24 cm) are sewed around the edges and inscribed with a rectangle (18 cm×18 cm). Samples are treated, air-dried, then subjected to five cycles of machine washing and drying (warm wash, high heat of drying) in combination with external ballast such as towels and articles of clothing. The dimensions of the rectangle are measured after five cycles, and the shrinkage is defined as the change in dimensions of the rectangle, after accounting for initial relaxation shrinkage.
The term "shrink-resistance" is a measure of the reduction in shrinkage (as defined above, after wash/dry cycles) for material that has been treated relative to material that has not been treated, i.e.,
Shrink-resistance=(Shrinkage.sub.untreated -Shrinkage.sub.treated)/Shrinkage.sub.treated
The value is multiplied by 100 in order to be expressed as a percentage.
The term "dye uptake" refers to properties associated with dyeing of fabrics, garments or yarn such as of wool or animal hair material. Dye uptake is a measure of the capacity of wool or animal hair material immersed in a dye solution to absorb available dyestuff. This property can be measured by the following test. In a suitable reaction vessel, wool or animal hair material is added to a buffered solution of acid black 172 (300 ml of 0.05 M NaOAc buffer, pH 4.5, plus 7.5 mL of a 1.0% w/w solution of acid black 172 in water). The vessel is incubated in a shaking water bath at 50° C. for 15 minutes with mild agitation. After removal of the material from solution, it is allowed to air-dry, then measured in a suitable spectrophotometer to determine CIELAB values. Dye uptake is determined by the L* reading, and changes in dye uptake are found by determining dL* relative to untreated material.
"Mote" particles are dark brown particles found on unbleached cotton fabric, also called "dark spots". They are cotton pod and stem residues originating from the mechanical picking of cotton. The brown color is due to the high lignin content of the mote particles.
Haloperoxidases
In the context of the present invention, the term "haloperoxidase" is intended to mean an enzyme selected from the group consisting of chloride peroxidase (EC 1.11.1.10), bromide peroxidase, and iodide peroxidase (EC 1.11.1.8).
A chloride peroxidase is an enzyme capable of oxidizing chloride, bromide and iodide ions with the consumption of H 2 O 2 .
A bromide peroxidase is an enzyme capable of oxidizing bromide and iodide ions with the consumption of H 2 O 2 .
A iodide peroxidase is an enzyme capable of oxidizing iodide ions with the consumption of H 2 O 2 .
Haloperoxidases form a class of enzymes capable of oxidizing halides (X=Cl--, Br--, or I--) in the presence of hydrogen peroxide to the corresponding hypohalous acid (HOX) according to the equation:
H.sub.2 O.sub.2 +X--+H+->H.sub.2 O+HOX
If an appropriate nucleophile is present, a reaction will occur with HOX, whereby bleaching may take place.
Haloperoxidases have been isolated from various organisms: mammals, marine animals, plants, algae, a lichen, fungi and bacteria (for reference see Biochimica et Biophysica Acta 1161, 1993, pp. 249-256). It is generally accepted that haloperoxidases are the enzymes responsible for the formation of halogenated compounds in nature, although other enzymes may be involved.
Haloperoxidases have been isolated from many different fungi, in particular from the fungus group dematiaceous hyphomycetes, such as Caldariomyces, e.g., C. fumago, Alternaria, Curvularia, e.g., C. verruculosa and C. inaequalis, Drechslera, Ulocladium and Botrytis (see U.S. Pat. No. 4,937,192).
According to the present invention, a haloperoxidase obtainable from Curvularia, in particular C. verruculosa, is preferred. Curvularia haloperoxidase and recombinant production thereof is described in WO 97/04102.
Haloperoxidase has also been isolated from bacteria such as Pseudomonas, e.g., P. pyrrocinia (for reference see The Journal of Biological Chemistry 263, 1988, pp. 13725-13732) and Streptomyces, e.g., S. aureofaciens (for reference see Structural Biology 1, 1994, pp. 532-537).
Bromide peroxidase has been isolated from algae (see U.S. Pat. No. 4,937,192).
In use, the concentration of the haloperoxidase may be varied in order to achieve the desired bleaching effect in the desired time frame. However, according to the invention, the haloperoxidase will normally be added in a concentration of 0.01-100 mg enzyme protein per liter, preferably in a concentration of 0.1-50 mg enzyme protein per liter, more preferably in a concentration of 1-10 mg enzyme protein per liter.
Halide Sources
According to the invention, the halide source for the reaction with haloperoxidase may be achieved in many different ways: The halide source may be sodium chloride, potassium chloride, sodium bromide, potassium bromide, sodium iodide, or potassium iodide. The concentration of the halide source will typically correspond to 0.01-1000 mM, preferably in the range of from 0.1-500 mM.
Hydrogen Peroxide Sources
According to the invention, the hydrogen peroxide needed for the reaction with the haloperoxidase may be achieved in many different ways: It may be hydrogen peroxide or a hydrogen peroxide precursor, such as percarbonate or perborate, or a peroxycarboxylic acid or a salt thereof, or it may be a hydrogen peroxide generating enzyme system, such as an oxidase and its substrate. Useful oxidases include glucose oxidase, a glycerol oxidase or an amino acid oxidase. An example of an amino acid oxidase is given in WO 94/25574.
According to the invention, the hydrogen peroxide source needed for the reaction with the haloperoxidase may be added in a concentration corresponding to a hydrogen peroxide concentration in the range of from 0.01-1000 mM, preferably in the range of from 0.1-500 mM.
Process
The chosen procedure will depend on the haloperoxidase in question, regarding pH optimum, temperature optimum, etc.
If a haloperoxidase from Curvularia verruculosa is used, the processing conditions could be: 30-70° C., pH 5, using 1-5 mg enzyme/liter, 50-500 mM halide (e.g. sodium chloride), 20 mM hydrogen peroxide, at a liquor/fabric ratio of from 4:1-30:1, for a reaction time of 30-120 min. (as illustrated in Example 1).
A buffer may be added to the reaction medium to maintain a suitable pH for the haloperoxidase used. The buffer may suitably be a phosphate, borate, citrate, acetate, adipate, triethanolamine, monoethanolamine, diethanolamine, carbonate (especially alkali metal or alkaline earth metal, in particular sodium or potassium carbonate, or ammonium and HCl salts), diamine, especially diaminoethane, imidazole, or amino acid buffer.
The process of the invention may be carried out in the presence of conventional fabric, garment, or yarn finishing agents, including wetting agents, polymeric agents, dispersing agents, etc.
A conventional wetting agent may be used to improve the contact between the substrate and the enzyme used in the process. The wetting agent may be a nonionic surfactant, e.g., an ethoxylated fatty alcohol. A very useful wetting agent is an ethoxylated and propoxylated fatty acid ester such as Berol 087 (product of Akzo Nobel, Sweden).
Examples of suitable polymers include proteins (e.g., bovine serum albumin, whey, casein or legume proteins), protein hydrolysates (e.g., whey, casein or soy protein hydrolysate), polypeptides, lignosulfonates, polysaccharides and derivatives thereof, polyethylene glycol, polypropylene glycol, polyvinyl pyrrolidone, ethylene diamine condensed with ethylene or propylene oxide, ethoxylated polyamines, or ethoxylated amine polymers.
The dispersing agent may suitably be selected from nonionic, anionic, cationic, ampholytic or zwitterionic surfactants. More specifically, the dispersing agent may be selected from carboxymethylcellulose, hydroxypropylcellulose, alkyl aryl sulphonates, long-chain alcohol sulphates (primary and secondary alkyl sulphates), sulphonated olefins, sulphated monoglycerides, sulphated ethers, sulphosuccinates, sulphonated methyl ethers, alkane sulphonates, phosphate esters, alkyl isothionates, acylsarcosides, alkyltaurides, fluorosurfactants, fatty alcohol and alkylphenol condensates, fatty acid condensates, condensates of ethylene oxide with an amine, condensates of ethylene oxide with an amide, sucrose esters, sorbitan esters, alkyloamides, fatty amine oxides, ethoxylated monoamines, ethoxylated diamines, alcohol ethoxylate and mixtures thereof. A very useful dispersing agent is an alcohol ethoxylate such as Berol 08 (product of Akzo Nobel, Sweden).
The bleaching processing may be performed in any machinery known in the art.
Inactivation of the haloperoxidase in question will normally not be necessary; however if an inactivation of the enzyme is wanted it may be performed as known in the art, e.g., high temperature and/or high pH, but the specific inactivation conditions will of course depend on the enzyme in use.
The fabric may be further finished by one or more of the following treatments as known in the art: dyeing, biopolishing, brightening, softening, and/or anti-wrinkling treatment(s).
Test Procedure
The test procedure for fabric bleaching may be performed visually and by using a Minolta Chroma Meter CR200, a Minolta Chroma Meter CR300 or a Minolta Chroma Meter 508i.
Evaluation: A Minolta Chroma Meter (available from Minolta Corp.) is used according to Manufacturer's instructions to evaluate the degree of bleaching as well as to estimate any discoloration using the change in the color space coordinates L*a*b* (CIELAB-system) : L* gives the change in white/black at a scale of from 0 to 100, a gives the change in green (-a*)/red (+a*), and b* gives the change in blue (-b*) /yellow (+b*) . A decrease in L* means an increase in black color (decrease of white color), an increase in L* means an increase in white color (a decrease in black color), a decrease in a* means an increase in green color (decrease in red color), an increase in a* means an increase in red color (a decrease in green color), a decrease in b* means an increase in blue color (a decrease in yellow color), and an increase in b* means an increase in yellow color (a decrease in blue color).
The instrument is calibrated using a standard calibration plate (white).
The invention is further illustrated in the following examples, which are not intended to be in any way limiting to the scope of the invention as claimed.
EXAMPLE 1
Bleaching of raw cotton swatches with Curvularia verruculosa haloperoxidase
Experimental conditions
The bleaching system contained 3 mg/l recombinant Curvularia verruculosa haloperoxidase with NaCl!=100 mM as substrate and H 2 O 2 !=20 mM as donor. pH was adjusted to pH=5.
The swatches were bleached for 60 minutes at 40° C. (The enzyme was produced as described in WO 97/04102).
The bleaching system was tested on twill cotton swatches and woven cotton swatches.
For twill fabric the fabric/liquor ratio was: 1 g of fabric in 15 ml of aqueous medium.
For woven fabric the fabric/liquor ratio was: 1 g of fabric in 20 ml of aqueous medium.
Results
Significant visual bleaching was obtained with the experimental conditions described above.
Note that the blind test assures that the observed bleaching effect is enzymatic in nature.
The bleaching results are presented in the Table 1 below:
______________________________________ΔL*/Δa*/Δb* on raw cotton swatches.sup.a.Bleachingsystem Twill.sup.b Woven.sup.b______________________________________Blind.sup.c (-)0.2/0.1/0.0 (-)0.2/0.0/(-)0.1Enzyme.sup.d 2.5/(-)0.9/(-)1.5 1.6/(-)0.6/(-)1.3______________________________________ .sup.a Measurements were all done on a Minolta 508i. Lamp was set to D65 and 2°. .sup.b Desized swatches obtained from Test Fabrics. .sup.c System consists of NaCl, hydrogen peroxide and acetate buffer. .sup.d System consists of haloperoxidase, NaCl, hydrogen peroxide and acetate buffer.
EXAMPLE 2
Bleaching of motes with Curvularia verruculosa haloperoxidase
Experimental conditions
The bleaching system was the same as described in Example 1: 3 mg/l recombinant Curvularia verruculosa haloperoxidase with NaCl!=100 mM as substrate and H 2 O 2 !=20 mM as donor. pH was adjusted to pH=5.
The swatches were bleached for 60 minutes at 40° C. in an Atlas LP2 Lauder-o-meter. Linen woven 100% cotton was supplied by Nordisk Textil V.ae butted.veri & Trykkeri A/S. The fabric/liquor ratio was 1 g of fabric in 20 ml of aqueous medium.
Results
Motes were counted on a fabric area of 10 cm×15 cm (on both sides).
A mote was defined as a "dark spot" on the cotton surface irrespective of size.
Double determination of the mote bleaching effect was carried out.
The numbers 1 and 2 in Table 2 refer to the separate fabric cloths used.
Note that a positive difference in mote count can be due to the motes splitting up due to the mechanical handling of the fabric cloth.
TABLE 2______________________________________ Mote count Mote count Difference before after in mote bleaching bleaching countSide of Side Side Side Side Side Sidefabric cloth 1 2 1 2 1 2______________________________________Reference 1.sup.a 85 74 91 71 +6 -3Reference 2.sup.a 78 68 69 70 -9 +2Blind 1.sup.b 60 50 62 52 +2 +2Blind 2.sup.b 72 74 77 75 +5 +1Enzymatic 1.sup.c 53 62 49 42 -4 -20Enzymatic 2.sup.c 68 62 41 56 -27 -6______________________________________ .sup.a Fabric washed in buffer only. .sup.b Conditions as described above in the experimental section but without added enzyme. .sup.c Conditions as described above in the experimental section.
The reference tests illustrate the effects of the mechanical washing procedure and as can be seen from Table 2, the loss of motes is ambiguous. (The mechanical washing procedure has no significant effect on the number of motes left on the cloth after the bleaching.)
Table 2 shows that there is a significant loss of motes when submitting the fabric cloth to the enzymatic bleaching conditions. The blind test assures that the observed effect is enzymatic in nature.
EXAMPLE 3
Treatment of wool with Curvularia verruculosa haloperoxidase
Experimental conditions
The enzyme system was the same as described in Example 1: 3 mg/l recombinant Curvularia verruculosa haloperoxidase with NaCl!=100 mM as substrate and H 2 O 2 !=20 mM as donor. pH was adjusted to pH=5.
Swatches (24 cm×24 cm, approx. 10 g each) of TF532 Jersey Knit Wool were cut and sewn around the edge with a surger. A permanent marker was used to draw an 18×18 rectangle on each swatch.
______________________________________Results: Shrinkage Treatment (%)______________________________________ Blind 29 Enzymatic 23______________________________________ | A method of treating fabrics, garments, or yarns comprising treating undyed fabric, garment, or yarn in an aqueous medium with an effective amount of a haloperoxidase, a halide source, and a hydrogen peroxide source. The treated fabric, garment, or yarn exhibits improved characteristics relative to untreated fabric, garment, or yarn, such as improved shrink-resistance. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a process for preparing thiophene derivatives and novel compounds obtained thereby and in more detail, this invention relates to a process for preparing a series of thiophene derivatives, from which 2-thiopheneacetic acids having or not having substituent or esters thereof can easily be prepared, in high yields and selectivity by using substituted or unsubstituted thiophenes as the starting materials by easy operations and novel compounds, i.e. α-arylthio-2-thiopheneacetic acids having or not having substituent or esters thereof, obtained in the course of the process.
2. Description of the Prior Art
Prior to the invention, it was known that the compounds represented by the general formula ##STR1## (wherein R 1 and R 2 are independently selected from hydrogen, halogen or lower alkyl group and X is chlorine or bromine) can be, for example, converted to useful insecticides structurally analogous to DDT by condensation with other aromatic compounds (e.g., H. D. Hartough, "The Chemistry of Heterocyclic Compounds"--Thiophene and its Derivatives, Interscience Publishers, Inc., New York, 1952, p. 189), and the carboxylates of the compounds with the general formula (I) themselves are reported to show insecticidal activities (R. C. Blinn et al., J. Amer. Chem. Soc., 76, 37 (1954)).
The process for the preparation of α-trihalomethyl-2-thiophenemethanols heretofore known to the art comprises the preparation of the Grignard reagent from a 2-bromothiophene and magnesium and then reacting the said reagent with trichloroacetaldehyde to give an α-trihalomethyl-2-thiophenemethanol (J. Amer. Chem. Soc., 71, 2859 (1949)). However, this process cannot be adopted commercially because of the difficulty in the selective synthesis of the starting material, i.e. 2-bromothiophene, and because the process disadvantageously requires an anhydrous condition and necessitates the use of flammable ethers as the reaction medium when preparing the Grignard reagent.
Also, processes for the preparation of α-substituted 2-thiopheneacetic acid derivatives having the general formula ##STR2## (wherein R 1 and R 2 are independently selected from hydrogen, halogen or lower alkyl group and R 3 is alkoxy group, hydroxyl group or amino group) heretofore known to the art are: (1) the condensation of a 2-thiophenealdehyde with bromoform in the presence of a base (J. Amer. Chem. Soc., 83, 2755 (1961)), (2) the oxidation of a 2-acetylthiophene with selenium dioxide and then treating with an alkali (Arkiv Kemi., 11, 519 (1957)), (3) the preparation of 2-thiophenealdehyde cyanohydrin and then conducting hydrolysis (Japanese Patent Disclosure No. 8775/73), (4) the addition of glyoxylic acid on thiophene (Japanese Patent Disclosure No. 49954/74), etc.
However, the process (1) necessitates the use of expensive bromoform and 2-thiophenealdehyde as the raw materials and the yield of the product is low. The process (2) necessitates the use of expensive and dangerous selenium dioxide and is difficult to adopt as a commercial process. The process (3) requires 2-thiophenealdehyde which is difficultly accessible commercially, and necessitates the use of highly poisonous hydrogen cyanide. Although the process (4) requires a shorter reaction step, yield of the product is low and is thus difficult to adopt as a commercial process.
Further, the process for the preparation of 2-thiopheneglycolic acid by the reduction of 2-thiopheneglyoxylic acid in an alcohol by the use of sodium amalgam was known prior to the invention (F. Ernst, Ber., 19, 3278 (1886)), however, commercial production by the process above is difficult, since the prior synthetic method gives 2-thiopheneglyoxylic acid in relatively low yield, which is required as the starting material.
It was known that the α-substituted 2-thiopheneacetic acid derivatives themselves can be converted to penicillin derivatives having antibiotical activities by reacting them with penicillanic acid derivatives (Cf. e.g. Netherlands Octrooiaanvrage No. 6506584), and 2-thiopheneacetic acids which are the compounds obtainable by replacing the substituent located in α-position of said α-substituted 2-thiopheneacetic acids with hydrogen are very useful as chemical modifier of penicillin and cephalosporin (Cf. J. Amer. Chem. Soc., 84, 3401 (1962)).
The main processes for the preparation of 2-thiopheneacetic acid heretofore known may be classified into three processes described below, according to the starting materials employed: (1) converting 2-chloromethylthiophene to 2-cyanomethylthiophene at first by treating with an alkali cyanide, and then conducting hydrolysis thereof (Japanese Patent Disclosure No. 46063/77); (2) converting by Willgerodt reaction of 2-acetylthiophene with ammonium polysulfide to 2-thiopheneacetamide at first and then conducting hydrolysis thereof (Otto Dann, Ger. Pat. No. 832755 (1952)), (3) (a) reacting potassium cyanide and an ester of chloroformic acid on 2-thiophenealdehyde to form an α-alkoxycarbonyloxy-2-thiopheneacetonitrile, and then conducting catalytic hydrogenation thereof to 2-cyanomethylthiophene, and further conducting hydrolysis thereof (M. J. Soulal, M. C. Woodford, British Pat. No. 1,122,658 (1968); (b) treating the condensation product of 2-thiophenealdehyde and methyl methylthiomethyl sulfoxide with hydrogen chloride in alcohol to form an ester of 2-thiopheneacetic acid and then conducting hydrolysis thereof (Japanese Patent Disclosure No. 46063/77); etc. However, the process (1) includes difficulties in that 2-chloromethylthiophene is difficult to handle because it is unstable, explosive, and is a lachrymatory substance, and also, highly poisonous bis(chloromethyl) ether is formed as by-product during the preparation of this compound. The process (2) possesses shortcomings in that it requires a high-temperature and high-pressure condition in performing the Willgerodt reaction, and requires severe conditions for the hydrolysis. Also, the process (3) (a) has its demerit in that it necessitates the use of highly poisonous cyanide compounds, and requires many reaction stages, etc. The process (3) (b) in disadvantageous in that it needs attention in handling, and produces sulfur compounds having strong unpleasant odor.
SUMMARY OF THE INVENTION
Accordingly, the object of this invention is to provide a process for preparing a series of thiophene derivatives, from which 2-thiopheneacetic acid having or not having substituent or esters thereof can easily be prepared, in high yields by using substituted or unsubstituted thiophenes as the starting material by easy operations, and novel compounds, i.e. α-arylthio-2-thiopheneacetic acids having or not having substituent and esters thereof are obtained in the course of the process.
To assist in understanding this invention, the process and products of the invention are given in a chemical scheme: ##STR3##
In the scheme shown above, R 1 and R 2 are independently selected from the group consisting of hydrogen, halogens and alkyl groups; R 3 is selected from the group consisting of alkoxyl groups, hydroxyl groups, amino groups, alkylthio groups and arylthio groups; R 4 represents hydrogen or an alkyl group; and X represents halogen atom and preferably one selected from the group consisting of chlorine, bromine and iodine.
In the scheme shown above, compounds (C) are novel compounds when R 3 is an arylthio group and the compounds are useful as an intermediate of the synthesis of the final product (D) of the process of this invention, i.e. 2-thiopheneacetic acids having or not having substituent or esters thereof.
In this invention, the process to prepare compounds (C) via compounds (B) from compounds (A) is developed by the inventors through intensive studies toward establishing a process which overcomes the disadvantages found in the prior art aforementioned and selectively affords only the desired compounds, and found that the desired compounds (B) can be prepared in a good yield by treating under an acidic condition, a substituted or unsubstituted thiophene with a trihaloacetaldehyde both of which are easily obtainable as industrial raw materials.
That is, the first object of this invention is to provide a process for preparing 2-thiopheneacetic acid derivatives (C) represented by the general formula ##STR4## which comprises reacting a thiophene derivative (A) having the general formula ##STR5## with a trihaloacetaldehyde represented by the general formula CX 3 CHO under an acidic condition to obtain an α-trihalomethyl-2-thiophenemethanol (B) having the general formula ##STR6## It is preferred to establish the acidic condition by the use of a Lewis acid, and then further reacting the reaction product thus obtained with a compound having the general formula R 3 H in the presence of an alkali or alkaline earth metal hydroxide and if desired, the reaction product is further esterified in any suitable manner known in the art, such as reacting with an alcohol having the general formula R 4 OH (wherein R 1 , R 2 , R 3 , R 4 and X are as defined before).
The compounds (C) thus obtained can easily be converted to compounds (D), i.e. 2-thiopheneacetic acids having or not having substituent or esters thereof which are the final products of the process of this invention by reduction.
The second object of this invention is, therefore, to provide a process for the preparation of 2-thiopheneacetic acids represented by the general formula: ##STR7## which comprises reacting a thiophene having or not having substituent represented by the general formula ##STR8## with a trihaloacetaldehyde represented by the general formula CX 3 CHO under an acidic condition to prepare an α-trihalomethyl-2-thiophenemethanol represented by the general formula ##STR9## at first, then reacting the α-trihalomethyl-2-thiophenemethanol thus obtained with a compound represented by the general formula R 3 H in the presence of an alkali or an alkaline earth metal hydroxide, and if desired, the product is further esterified by reacting with an aliphatic alcohol to obtain an α-substituted 2-thiopheneacetic acids represented by the general formula ##STR10## and then the α-substituted 2-thiopheneacetic acid thus prepared is subjected to hydrogenation (wherein R 1 , R 2 , R 3 , R 4 and X are as defined before).
The third object of this invention is to provide novel compounds, i.e. α-substituted 2-thiopheneacetic acids represented by the general formula ##STR11## (wherein R 3 represents an arylthio group; R 1 , R 2 and R 4 are defined before).
Other object of this invention will become apparent during the following detailed description of the invention.
DETAILED DESCRIPTION OF THE INVENTION
As examples of one of the starting materials of the present invention represented by the general formula ##STR12## (wherein R 1 and R 2 are as defined before), thiophene, 2-chlorothiophene, 2-bromothiophene, 2,3-dichlorothiophene, 2-methylthiophene, 2-ethylthiophene, 2-methyl-3-chlorothiophene, 2-chloro-3-methylthiophene, etc. may be cited. As examples of the other starting compound represented by the general formula CX 3 CHO (wherein X is as aforementioned), trichloroacetaldehyde, tribromoacetaldehyde, etc. may be cited.
The present invention requires as the indispensable matter to treat the two starting materials described above under an acidic condition, and the acidic condition can be established by the presence of an inorganic acid such as sulfuric acid and phosphoric acid, an ion-exchange resin in which such acid is supported on a polymer substance, or a Lewis acid such as titanium tetrachloride, stannic tetrachloride, boron trifluoride, iron chloride and aluminum chloride. The use of a Lewis acid is particularly preferred. It is usually sufficient to use an equimolar amount of such acidic substance, but in the reaction of this kind in general, the reaction may proceed beyond the desired stage in some cases to afford 1,1-dithienylethanes as by-products. It is preferable to conduct the reaction in the presence of titanium tetrachloride and/or a titanium alkoxide in order to prevent or minimize the formation of such by-products. The usual solvents for Friedel-Crafts reactions, namely an aliphatic hydrocarbon such as hexane and heptane, a halogenated hydrocarbon such as methylene chloride and trichloroethane, and carbon disulfide, and, if desired, ethers may be used as the solvent without disadvantage. Usually, the reaction proceeds at room temperature, but if desired, the reaction may be accelerated by heating.
As described above, 1,1-dithienylethanes may be formed as by-products in some cases, and to avoid the formation of such by-products, reaction solvents may be used, or the formation of the by-products may be reduced by adopting a procedure which allows only the starting materials to recycle and come into contact with the catalyst by utilizing the boiling point difference between the starting materials and the products.
Under such conditions as described above, α-trihalomethyl-2-thiophenemethanols (B) above can be formed in high yields. The compounds, after isolation or without isolation, can be used for the treatment of the next step.
The second step comprises the reaction of an α-trihalomethyl-2-thiophenemethanol (B) above with a compound represented by the general formula R 3 H. As examples of compounds R 3 H, water, an alcohol such as methanol, ethanol, isopropanol, and butanol, a thiol such as methyl mercaptan, ethyl mercaptan, isopropyl mercaptan, thiophenol, and tolyl mercaptan, and an amine such as ammonia, methylamine, ethylamine, isopropylamine, dimethylamine and diethylamine and the like may be cited.
The second step requires as the indispensable condition, the use of an alkali or an alkaline earth metal hydroxide as the condensation reagent, and the use of sodium hydroxide or potassium hydroxide is preferred from an economical view. It is preferable to use at least 3 molar equivalents of these bases to compounds (B), and the desired compounds (C) can generally be prepared selectively by the use of 3 to 4 molar equivalent amounts of a base. It is preferable to use solvents in conducting the reaction, and when the compound represented by the general formula R 3 H is an alcohol, for example, an excess of the alcohol R 3 H may be used as the solvent. When a thiol or an amine is used as the compound represented by R 3 H, an alcohol may be used as the solvent, and in this case, the thiol or amine react preferentially because of the difference in the reaction rates. As in the case of the first step, the reaction of this step proceeds even at room temperature, but it is preferred to operate the reaction at the reflux temperature of the solvent used in order to accelerate the reaction and to selectively obtain only the desired compounds.
Further, the α-substituted 2-thiopheneacetic acid derivatives (C) prepared in accordance with the process described above can be readily converted to 2-thiopheneacetic acids having or not having substituent or esters thereof (D) by reductive treatment.
With regard to the reductive treatment, it is possible to perform the reduction by the following methods depending upon the kind of the R 3 substituent of the general formula (C). Thus, when R 3 is an alkoxyl group, a nickel-type catalyst such as Raney-nickel, a palladium-type catalyst such as palladium-charcoal, or a platinum catalyst may be used. These catalysts are commonly used for catalytic hydrogenation reactions of benzyl ethers. Water, acetone, a hydrocarbon solvent or an ether solvent may be exemplified as the solvent. The reaction can be performed at room temperature and under atmospheric pressure. In order to improve the selectivity of the reaction, a mineral acid such as hydrochloric acid and sulfric acid, or a mineral or an organic base such as sodium or potassium hydroxide, sodium or potassium acetate, triethylamine, pyridine, etc. may be added. Besides the catalytic hydrogenation described above, the reduction treatment by the use of hydrogen halide, and particularly hydrogen iodide, red phosphorus and hydrogen iodide (or iodine), or red phosphorus and hydrochloric acid may be used as the general reductive procedure. The reaction is performed, preferably, in a water-acetic acid system, but other solvents such as acetone, hydrocarbon solvents and ether solvents which do not directly affect the reaction may be allowed to co-exist, and the reaction is generally completed by heating under reflux.
When R 3 is a hydroxyl group, the reduction method by the use of stannous chloride and hydrochloric acid, and the catalytic hydrogenation method by the use of cooperchromium oxide or molybdenum sulfide may be exemplified as the general reduction method, in addition to the catalytic hydrogenation method and the reduction method by the use of a hydrogen halide as exemplified above in the case of the alkoxyl group derivatives.
When R 3 is an alkylthio group or an arylthio group, the conventional reductive desulfurization methods for α-thiocarboxylic acids can be used. Namely, the method by the use of a combination of zinc and an acid such as acetic acid, hydrochloric acid, or sulfuric acid, or by the use of aluminum amalgam or zinc amalgam or the method using a nickel-type catalyst such as Raney-nickel, can be utilized.
When R 3 is an amino group, the method employing a nickel-type catalyst such as Raney-nickel or a palladium-type catalyst such as palladium-charcoal may be exemplified.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the followings, the invention will be explained in more detailed and material fashion by illustration of Examples, however, please note that these Examples are given only for the purpose of illustration and are not to be construed as limiting this invention thereto. Tetramethylsilane was used as the internal standard in NMR measurement and the values were shown by δ, in ppm.
EXAMPLE 1
Thiophene (4.2 g, 50 mmol) and trichloroacetaldehyde (7.35 g, 50 mmol) were dissolved in n-heptane (25 ml). The solution was heated under reflux for 3.5 hr. under a Soxleht apparatus in which Amberlyst 15 (4.2 g) had been placed. After cooling, the n-heptane solution was concentrated, and the residue was purified by distillation to give 2.32 g of α-trichloromethyl-2-thiophenemethanol boiling at 98°-100° C./1.0 mmHg.
EXAMPLE 2
To a solution of titanium tetrachloride in methylene chloride (1 molar concentration; 30 ml, 30 mmol), titanium tetraisopropoxide (4.26 g, 15 mmol) was added under an argon atmosphere with stirring and under water cooling. After 10 min., thiophene (2.52 g, 30 mmol) was added and then trichloroacetaldehyde (8.82 g, 60 mmol) was added dropwise during 10 min. with stirring and under ice-water cooling. After the addition was completed, stirring was continued for further 10 min., and then water and methylene chloride were added successively, and the organic layer was separated. The organic layer was washed with water and dried over anhydrous magnesium sulfate. The solution was filtered and, after removal of the solvent by distillation under a reduced pressure with an aspirator, the residue was distilled to form trichloroacetaldehyde isopropyl alcoholate initially and then 5.0 g of α-trichloromethyl-2-thiophenemethanol.
Yield: 72% (based on thiophene).
bp: 95°-97° C./0.7 mmHg (Literature value: 140°-142° C./10 mmHg).
IR (cm -1 ): 3425, 1065, 1044, 822 and 710.
NMR (CDCl 3 ): 3.48 (d, J=5 Hz, 1H), 5.40 (d, J=5 Hz, 1H) and 6.88-7.50 (m, 3H).
EXAMPLE 3
Titanium tetraisopropoxide (2.13 g, 7.5 mmol) was dissolved in methylene chloride (10 ml). To the solution, titanium tetrachloride solution in methylene chloride (1 molar solution, 30 ml, 30 mmol) was added. The mixture was cooled to -70° C. and then, trichloroacetaldehyde (8.8 g, 59.7 mmol) was added thereto. Further, 2-chlorothiophene (3.56 g, 30 mmol) solution in methylene chloride (10 ml) was added into the mixture. The mixture was kept at the same temperature under agitation for 1 hr. and then, the temperature was raised slowly to -10° C. The reaction mixture was poured into ice-water and the organic layer was separated. The organic layer was washed with sodium chloride solution in water and dried with magnesium sulfate. After removal of solvent, vacuum distillation was conducted. Thereby, 2,2,2-trichloro-1-(5-chlorothiophene-2)-ethanol (3.52 g, 44%) was obtained.
bp: 94°-100° C./0.15 mmHg
NMR (CCl 4 ): 3.20 (d, J=4 Hz, 1H), 5.20 (d, J=4 Hz, 1H), 6.72 (d, J=4 Hz, 1H) and 6.97 (d, J=4 Hz, 1H).
EXAMPLE 4
Under an argon atmosphere, potassium hydroxide (1.12 g, 20 mmol) was dissolved in methanol (10 ml). A solution of α-trichloromethyl-2-thiophenemethanol (1.16 g, 5 mmol) in methanol (3 ml) was added with stirring and under water cooling. After 10 min., the mixture was heated up gradually and heated under reflux for 1 hr. with vigorous stirring. It was cooled to room temperature, most of the solvent was removed by distillation under a reduced pressure, diethylether was then added and the mixture was decomposed with dilute hydrochloric acid. The ether layer was separated and the water layer was extracted with ethyl acetate. The organic layers thus obtained were combined to one layer and was washed with an aqueous solution of sodium chloride and dried with anhydrous sodium sulfate. After filtration, the filtrate was concentrated under a reduced pressure to give 620 mg of α-methoxy-2-thiopheneacetic acid.
Yield: 73%.
IR (cm -1 ): 3100, 2925, 1730, 1180, 1100, 880, 845 and 707.
NMR (CDCl 3 ): 3.38 (s, 3H), 5.00 (s, 1H), 6.81-7.40 (m, 3H) and 10.58 (s, 1H).
EXAMPLE 5
Under an argon atmosphere, potassium hydroxide (1.12 g, 20 mmol) was dissolved in methanol (10 ml). Thiophenol (0.6 g, 5.45 mmol) was added to this solution with stirring and under water cooling. After 10 min., a solution of α-trichloromethyl-2-thiophenemethanol (1.16 g, 5 mmol) in methanol (3 ml) was added. After 10 min., the mixture was gradually heated up and was heated under reflux for 2 hr. with vigorous stirring. After cooling to room temperature and after removal of most of the solvent by distillation under a reduced pressure, diethylether was added and the mixture was decomposed with dilute hydrochloric acid. The ether layer was separated, washed with water, and dried with anhydrous magnesium sulfate. After filtration, the filtrate was concentrated under a reduced pressure and the residue was purified by silica gel column chromatography (ethyl acetate: n-hexane=1:4) to give 940 mg of α-phenylthio-2-thiopheneacetic acid as a viscous oil.
Yield: 76%.
IR (cm -1 ): 3060, 1715, 1587, 1485, 1440, 1416, 1253, 750, 705 and 694.
NMR (CDCl 3 ): 5.03 (s, 1H), 6.62-7.60 (m, 8H) and 11.47 (s, 1H).
EXAMPLE 6
Into 20 ml of ethanol, α-trichloromethyl-2-thiophenemethanol (2.32 g, 10 mmol) was dissolved and an aqueous solution of sodium methyl mercaptide (20%, 10 g, 29 mmol) was further added thereto. Into the solution, potassium hydroxide (2.4 g, 36 mmol) solution in ethanol (20 ml) was added in drop-wise. After the addition was completed, the reaction mixture was agitated for 30 min. at room temperature. Thereafter, the temperature was raised to 50° C. and agitation was further conducted for 5 hr. at the temperature, then, the solvent was distilled off under vacuum. The residue thus obtained was dissolved in water and was washed with methylene chloride. After being acidified with hydrochloric acid, extraction was conducted with methylene chloride. After drying of the organic layer with magnesium sulfate, the organic layer was concentrated. Thereby, crude α-methylthio-2-thiopheneacetic acid (1.75 g, 93%) was obtained. After purification with silica gel chromatography, 1.66 g (88%) of pure product was obtained.
NMR (CCl 4 ): 1.98 (s, 3H), 4.67 (s, 1H), 6.75-6.97 (m, 1H), 7.00-7.28 (m, 2H) and 11.95 (s, 1H).
EXAMPLE 7
Into 2.4 ml of water, potassium hydroxide (0.67 g, 12 mmol) and lithium chloride (0.254 g, 6 mmol) were dissolved. Then, into the solution above, α-trichloromethyl-2-thiophenemethanol (0.693 g, 3 mmol) solution in dioxane (2.4 ml) was added and agitation was conducted for 12 hr. at room temperature and for 3 hr. at 80° C. Thereafter, water (20 ml) was added thereto and diethylether was further added into the reaction mixture. The ether soluble part was separated. The water layer was acidified with hydrochloric acid and then, extracted with diethylether. The organic layer was dried with anhydrous magnesium sulfate and was treated with activated carbon and filtered. Thereafter, the filtrate was concentrated and gave 0.246 g of 2-thiopheneglycolic acid as crystals.
Crude yield: 52%.
NMR (CDCl 3 ): 5.47 (s, 1H), 6.80-7.35 (m, 3H) and 8.52 (broad s, 2H).
EXAMPLE 8
α-Phenylthio-2-thiopheneacetic acid (890 mg, 3.56 mmol) was dissolved in acetic acid (6 ml), then zinc dust (350 mg, 5.4 mmol) was added and the mixture was heated under reflux with vigorous stirring. After 30 min., zinc dust (350 mg, 5.4 mmol) was added again, and the mixture was heated under reflux for another 4 hr. with stirring, then cooled to room temperature, and most of the solvent was removed by distillation. Water and ethyl acetate were added and the precipitate was filtered off by the use of celite, and the layers of the filtrate were separated. The organic layer was washed with an aqueous solution of sodium chloride and dried with anhydrous magnesium sulfate. After filtration, the solution was concentrated under a reduced pressure and the crystals thus obtained were further recrystallized from ethyl acetate: n-hexane to give 2-thiopheneacetic acid (430 mg) melting at 62° C. (literature value: 62°-65° C.).
Yield: 85%.
EXAMPLE 9
Red phosphorous (180 mg) and iodine (60 mg) were added to acetic acid (2.85 ml), and the mixture was stirred for 30 min. A solution of water (60 mg) and α-methoxy-2-thiopheneacetic acid (860 mg, 5 mmol) in acetic acid (1.5 ml) was added to this mixture and the resulting mixture was heated under reflux for 2 hr. with vigorous stirring. After cooling to room temperature, water and ethyl acetate were added thereto. After filtering off the precipitate by the use of celite, the organic layer was separated. It was washed with saturated aqueous solution of sodium chloride and dried with anhydrous magnesium sulfate. After filtration, the solution was concentrated under a reduced pressure, and the crystals which remained were recrystallized from ethyl acetate:n-hexane to give 2-thiopheneacetic acid (610 mg) melting at 62° C. (Literature value: 62°-65° C.).
Yield: 86%. | Process for the preparation of a series of thiophene derivatives, from which 2-thiopheneacetic acid derivatives can easily be prepared, in high yields and selectivity by using substituted or unsubstituted thiophenes as the starting materials by easy operations. 2-Thiopheneacetic acid derivatives are very useful compounds as the chemical modifier of penicillin and cephalosporin. Novel compounds, i.e. α-arylthio-2-thiopheneacetic acids are also disclosed. These compounds are useful as the intermediates of the synthesis of 2-thiopheneacetic acids. | 2 |
REFERENCE TO RELATED APPLICATION
This application is a Divisional Application of U.S. Ser. No. 14/330,914, entitled “LED ARRAY”, filed on Jul. 14, 2014, issued on Dec. 1, 2015 as U.S. Pat. No. 9,202,981, which is a division of U.S. patent application Ser. No. 14/065,330, entitled “LED ARRAY”, filed on Oct. 28, 2013, issued on Jul. 15, 2014 as U.S. Pat. No. 8,779,449, which is a division of U.S. patent application Ser. No. 13/428,974, entitled “LED ARRAY”, filed on Mar. 23, 2012, issued on Oct. 29, 2013 as U.S. Pat. No. 8,569,775, which claims the right of priority based on Taiwan patent application Ser. No. 100110029, filed Mar. 23, 2011, issued on Jun. 11, 2015 as TW Patent No. 1525852, the entireties of which are incorporated by reference herein.
TECHNICAL FIELD
The application relates to an LED structure, and more particularly to an LED structure having a first epitaxial unit and a second epitaxial unit.
DESCRIPTION OF BACKGROUND ART
Recently, based on the progress of epitaxy process technology, the light-emitting diode (LED) becomes one of the potential solid-state lighting (SSL) source. Due to the limitation of physics mechanism, LEDs can only be driven by DC power source. Thus the regulator circuit, buck circuit, and other electronic devices are necessary for every lighting device using LED as lighting source to convert AC power source into DC power source to drive LED. However, the addition of the regulator circuit, buck circuit, and other electronic device raises the cost of lighting device using LED as lighting source and causes the low AC/DC conversion efficiency and the huge lighting device package also affect the reliability and shorten the lifetime of LED in daily use.
SUMMARY OF THE DISCLOSURE
The present application discloses a light-emitting diode structure comprises a first epitaxial unit; a second epitaxial unit separated from the first epitaxial unit; a crossover metal layer comprising a first protruding portion entering the first epitaxial unit; a conductive layer separated from the crossover metal layer and comprising a second protruding portion entering the second epitaxial unit; a conductive connecting layer surrounding the first protruding portion; and an electrode arranged on the conductive connecting layer.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-1I are the cross sectional views of the LED array in accordance of the first embodiment of present application.
FIGS. 1A ′- 1 G′ are the top views of the first embodiment of LED array disclosed by present application.
FIGS. 2A-2I are the cross sectional views of the second embodiment of LED array disclosed by present application.
FIGS. 2A ′- 2 G′ are the top views of the second embodiment of LED array disclosed by present application.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present application discloses an LED array having N light-emitting diode units (N≧3) comprising a first light-emitting diode unit, a second light-emitting diode unit in sequence to the (N−1) th light-emitting diode unit and an N th light-emitting diode unit. The LED array further comprises a first area (I), the second area (II), and the third area (III). The first area (I) comprises the first light-emitting diode unit, the third area (III) comprises the N th light-emitting diode unit, and the second area (II) locates between the first area (I) and the third area (III) and comprises the second light-emitting diode unit in sequence to the (N−1) th diode units.
The first embodiment discloses a first LED array 1 having three light-emitting diode units. FIGS. 1A to 1I illustrate the cross sectional views and the FIGS. 1A ′ to 1 G′ illustrate the top views of the first embodiment of the first LED array 1 . The method for manufacturing the first LED array 1 comprises steps of:
1. Providing a temporary substrate 11 , and forming an epitaxial structure thereon. The epitaxial structure comprises a first conductive semiconductor layer 12 , an active layer 13 , and a second conductive semiconductor layer 14 as illustrated in FIGS. 1A and 1A ′. 2. Next, forming multiple trenches 15 by partially etching the epitaxial structure in the first area (I) and the second area (II), and the epitaxial structure not etched forms multiple flat planes 16 , and the epitaxial structure of the third area (III) is not etched as illustrated in FIGS. 1B and 1B ′. 3. Forming a conductive connecting layer 17 on partial regions of the flat planes 16 , and the area of the flat planes 16 uncovered by the conductive connecting layer 17 forms multiple pathways 18 as illustrated in FIGS. 1C and 1C ′. 4. Forming a first isolation layer 19 on part of the conductive connecting layer 17 , the multiple pathways 18 , and the side wall of the multiple trenches 15 , while the conductive connecting layer 17 in the third area (III) and part of the conductive connecting layer 17 in the first area (I) are not covered by the first isolation layer 19 . The conductive connecting layer 17 not covered by the first isolation layer 19 in the second area (II) is defined as a conductive region 20 as illustrated in FIGS. 1D and 1D ′. 5. Forming a crossover metal layer 21 on the first isolation layer 19 , the conductive region 20 , in multiple trenches 15 , and on the conductive connecting layer 17 in the third area (III). A part of the conductive connecting layer 17 in the first area (I) is not covered by the crossover metal layer 21 in order to electrically connect the second conductive layer 23 with the second conductive semiconductor layer 14 in the following steps. The region which is not covered by the crossover metal layer 21 in the second area (II) nearby the conductive region 20 is used for electrical isolation as illustrated in the FIGS. 1E and 1E ′. Part of the crossover metal layer 21 in the first area (I) extends to multiple trenches 15 and electrically connects to the first conductive semiconductor layer 12 . The crossover metal layer 21 on multiple flat planes 16 and the pathways 18 in the first area (I) is electrically isolated from the second conductive semiconductor layer 14 by the first isolation layer 19 . The crossover metal layer 21 on the conductive region 20 in the second area (II) electrically connects with the second conductive semiconductor layer 14 by the conductive connecting layer 17 . Part of the crossover metal layer 21 in the second area (II) extends to multiple trenches 15 and electrically connects to the first conductive semiconductor layer 12 . The crossover metal layer 21 on multiple flat planes 16 and the pathways 18 in the second area (II) is electrically isolated from the second conductive semiconductor layer 14 by the first isolation layer 19 . The crossover metal layer 21 in the third area (III) is electrically connected with the second conductive semiconductor layer 14 by the conductive connecting layer 17 . 6. Forming a second isolation layer 22 on the crossover metal layer 21 and the region a in the second area (II). But part of the conductive connecting layer 17 in the first area (I) is not covered by the second isolation layer 22 as illustrated in the FIGS. 1F and 1F ′. 7. Forming the second conductive layer 23 on the second isolation layer 22 and part of the conductive connecting layer 17 as illustrated in the as illustrated in the FIGS. 1G and 1G ′. 8. Forming a bonding layer 24 on the second conductive layer 23 which is bonded with a permanent substrate 25 by the bonding layer 24 as illustrated in the FIG. 1H . 9. Removing the temporary substrate 11 to expose the first conductive semiconductor layer 12 and roughening the surface of the first conductive semiconductor layer 12 . Next, etching multiple pathways 18 from the first conductive semiconductor layer 12 until the first isolation layer 19 is revealed in order to form N light-emitting diode units. Among the N light-emitting diode units, the first light-emitting diode unit locates in the first area (I), the second to the (N−1) th light-emitting diode units locate in the second area (II), and the N th light-emitting diode unit locates in the third area (III). At last, forming a first electrode layer 27 on the roughed surface of the first conductive semiconductor layer 12 in the N th light-emitting diode unit. Thus an LED array 1 having N light-emitting diode units electrically connected in serial by the crossover metal layer 21 is formed as illustrated in FIG. 1I .
The second embodiment discloses a second LED array 2 having three light-emitting diode units. FIGS. 2A to 21 illustrate the cross sectional views and the FIGS. 2A ′ to 2 G′ illustrate the top views of the second embodiment of LED array 2 . The method for manufacturing the second LED array 2 comprises steps of:
1. Providing a temporary substrate 11 , and forming an epitaxial structure thereon. The epitaxial structure comprises a first conductive semiconductor layer 12 , an active layer 13 , and a second conductive semiconductor layer 14 as illustrated in FIGS. 2A and 2A ′. 2. Next, forming multiple trenches 15 by partially etching the epitaxial structure in the first area (I), the second area (II), and the third area (III), and the epitaxial structure not etched forms multiple flat planes 16 as illustrated in FIGS. 2B and 2B ′. 3. Forming a conductive connecting layer 17 on partial regions of the flat planes 16 , and the area of the flat planes 16 uncovered by the conductive connecting layer 17 forms multiple pathways 18 as illustrated in FIGS. 2C and 2C ′. 4. Forming a first isolation layer 19 on part of the conductive connecting layer 17 , the multiple pathways 18 , and the side wall of the multiple trenches 15 . The conductive connecting layer 17 in the second area (II) and the third area (III) which is not covered by the first isolation layer 19 are defined as a conductive region 20 as illustrated in FIGS. 2D and 2D ′. 5. Forming a crossover metal layer 21 on the first isolation layer 19 , the conductive region 20 , and in the multiple trenches 15 except those in the third area (III). A part of the first isolation layer 19 in the first area (I) is not covered by the crossover metal layer 21 in order to electrically isolate the first conductive layer 26 from the second conductive semiconductor layer 14 in the following steps. The first isolation layer 19 in multiple trenches 15 and flat planes 16 is not covered by the crossover metal layer 21 in order to electrically isolate the first conductive layer 26 from the second conductive semiconductor layer 14 in the following steps as illustrated in the FIGS. 2E and 2E ′. A part of the crossover metal layer 21 in the first area (I) extends to multiple trenches 15 and electrically connects to the first conductive semiconductor layer 12 . The crossover metal layer 21 on multiple flat planes 16 and the pathways 18 in the first area (I) is electrically isolated from the second conductive semiconductor layer 14 by the first isolation layer 19 . The crossover metal layer 21 on the conductive region 20 in the second area (II) electrically connects with the second conductive semiconductor layer 14 by the conductive connecting layer 17 . A part of the crossover metal layer 21 in the second area (II) extends into the multiple trenches 15 and electrically connects to the first conductive semiconductor layer 12 . The crossover metal layer 21 on multiple flat planes 16 and the pathways 18 in the second area (II) is electrically isolated from the second conductive semiconductor layer 14 by the first isolation layer 19 . The crossover metal layer 21 on the conductive region 20 in the third area (III) electrically connects with the second conductive semiconductor layer 14 by the conductive connecting layer 17 . Besides, the region b in the second area (II) and the third area (III) adjacent to the conductive region 20 is not fully covered by the crossover metal layer 21 which is used for electrical isolation. 6. Forming a second isolation layer 22 on the crossover metal layer 21 , the part of the first isolation layer 19 in the first area (I), and on the region b which is not fully covered by the crossover metal layer 21 in the second area (II). The second isolation layer 22 does not cover the inner side of the trenches 15 in the third area (III), the first isolation layer 19 of the multiple flat planes 16 , and the region b which is not fully covered by the crossover metal layer 21 in the third area (III) as illustrated in the FIGS. 2F and 2F ′. 7. Forming the first conductive layer 26 on the second isolation layer 22 , in the multiple trenches 15 in the third area (III), on the first isolation layer 19 of the flat planes 16 , and the region b which is not fully covered by the crossover metal layer 21 in the third area (III) as illustrated in the FIGS. 2G and 2G ′. 8. Forming a bonding layer 24 on the first conductive layer 26 which is bonded with a permanent substrate 25 by the bonding layer 24 as illustrated in the FIG. 2H . 9. Removing the temporary substrate 11 to expose the first conductive semiconductor layer 12 and roughs the surface of the first conductive semiconductor layer 12 . Next, etching multiple pathways 18 form the first conductive semiconductor layer 12 until the first isolation layer 19 is revealed in order to form N light-emitting diode units. Among the N light-emitting diode units, the first light-emitting diode unit locates in the first area (I), the second to the (N−1) th light-emitting diode units locate in the second area (II), and the N th light-emitting diode unit locates in the third area (III). Next, etching the first conductive semiconductor layer 12 in the first area (I) without the crossover metal layer 21 until the conductive connecting layer 17 is revealed, and forming a second electrode layer 28 on the conductive connecting layer 17 . Thus an LED array 2 having N light-emitting diode units electrically connected in series by the crossover metal layer 21 is formed as illustrated in FIG. 21 .
The temporary substrate 11 described in the above first and second embodiments is made of, for example, gallium arsenide (GaAs), gallium phosphide (GaP), sapphire, silicon carbide (SiC), gallium nitride (GaN), or aluminum nitride. The epitaxial structure is made of an III-V group semiconductor material which is the series of aluminum gallium indium phosphide (AlGaInP) or the series of aluminum gallium indium nitride (AlGaInN). The conductive connecting layer 17 comprises indium tin oxide, cadmium tin oxide, antimony tin oxide, indium zinc oxide, aluminum zinc oxide, and zinc tin oxide. The first isolation layer 19 and the second isolation layer 22 can be made of an insulating material comprises silicon dioxide, titanium monoxide, titanium dioxide, trititanium pentoxide, titanium sesquioxide, cerium dioxide, zinc sulfide, and alumina. The first conductive layer 26 and the second conductive layer 23 can be made of silver or aluminum. The bonding layer 24 is an electrically conductive material made of metal or its alloys such as AuSn, PbSn, AuGe, AuBe, AuSi, Sn, In, Au, or PdIn. The permanent substrate 25 is a conductive material such as carbides, metals, metal alloys, metal oxides, metal composites, etc. The crossover metal layer 21 comprises metal, metal alloys, and metal oxides.
Although the present application has been explained above, it is not the limitation of the range, the sequence in practice, the material in practice, or the method in practice. Any modification or decoration for present application is not detached from the spirit and the range of such. | A light-emitting diode structure comprises a first epitaxial unit; a second epitaxial unit separated from the first epitaxial unit; a crossover metal layer comprising a first protruding portion entering the first epitaxial unit; a conductive layer separated from the crossover metal layer and comprising a second protruding portion entering the second epitaxial unit; a conductive connecting layer surrounding the first protruding portion; and an electrode arranged on the conductive connecting layer. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to an apparatus and method for reducing nitric oxide (NOx) emissions and cooling the combustion liner for a can-annular gas turbine combustion system. Specifically, an apparatus and method for introducing the cooling air into the premix chamber of the combustion system that minimizes the use of compressor discharge air for cooling the combustion liner as well as for improving the mixing of fuel and air prior to the combustion process.
2. Description of Related Art
Combustion liners are commonly used in the combustion section for most gas turbine engines. The combustion section is located between the compressor and turbine, and depending upon the application, the combustion section may not be located along the centerline of the engine, but may be located around the centerline or even perpendicular to the engine orientation. Combustor liners serve to protect the combustor casing and surrounding engine from the extremely high operating temperatures by containing the chemical reaction that occurs between the fuel and air.
Recent government emission regulations have become of great concern to both gas turbine manufacturers and operators. Of specific concern is nitric oxide (NOx) due to its contribution to air pollution. While NOx emissions are of some concern to aircraft engines, greater concerns include engine weight, performance, safety and fuel efficiency. While these concerns are shared by the industrial gas turbine engine market, NOx emissions rank as one of the greatest concerns. Utility sites have governmental permits that allow specific amounts of emissions each year. Lower emission rates, especially NOx, allow engines to run longer hours and hence generate more revenue.
It is well known that NOx formation is a function of flame temperature, air inlet temperature, residence time, and equivalence ratio. Nitric oxide emissions have been found to be lower for lower flame temperature, lower air inlet temperature, shorter residence time, and lower equivalence ratio, or a leaner fuel mixture. Lower flame temperatures and lower equivalence ratios can be accomplished by increasing the amount of air used in the combustion process, for a given amount of fuel. Further reductions in emissions can be accomplished by improving the utilization of the cooling air.
The present invention is used in a dry, low NOx gas turbine engine, which is typically used to drive electrical generators. Each combustor includes an upstream premix fuel/air chamber and a downstream, or secondary, combustion chamber, separated by a venturi having a narrow throat constriction. The present invention is concerned with improving the mixing of fuel and air in the premix zone as well as the cooling of the combustion liner to further reduce nitric oxide emissions.
Prior methods of cooling combustion liners vary extensively. U.S. Pat. No. 4,292,801 and U.S. Pat. No. 5,127,221 describe louver film cooling and transpiration cooling, respectively, for similar dual-stage, dual-mode combustors. Backside impingement cooling is described in U.S. Pat. No. 5,117,636. Though these methods of cooling have proven adequate throughout the engine operating cycle, enhancements can be made to further reduce pollutants from the combustor, while improving cooling effectiveness.
Over the years, some annular gas turbine combustor designers have incorporated angled film cooling holes, specifically for improving cooling efficiency. Typically, annular combustors are used for aircraft applications where small size and reduced weight are important design factors. Angled film cooling holes improve cooling efficiency by increasing the amount of internal surface area that is available for heat removal. For example, a hole drilled at 20 degrees to the liner wall has nearly three times as much surface area as a hole drilled normal to the liner surface. In addition, angled film cooling holes provide a jet of air to form a better film along the liner surface. In order to accomplish this improved cooling, thicker liner walls are typically required, which further increase hole surface area, hence an increase in liner weight. Examples of annular aircraft combustors utilizing this cooling technique are discussed in U.S. Pat. No. 5,233,828; U.S. Pat. No. 5,181,379; U.S. Pat. No. 5,279,127; and U.S. Pat. No. 5,261,223. This technique is also used in an annular liner dome plate as described in U.S. Pat. No. 5,307,637, and to provide differential cooling to accommodate hot spots on annular combustor liner surfaces, as discussed in U.S. Pat. No. 5,241,827.
Of greater importance to reduce NOx emission than the improved cooling is the improved mixing of the air with fuel for combustion. When cooling performance is improved, less air is typically required for cooling and more can be dedicated to fuel/air mixing. More air into the combustion process will lower fuel to air ratios and hence equivalence ratio as well as lower flame temperature, which, as explained earlier, are two key drivers of NOx emissions. The increased air for the combustion process can be delivered through the front end of the combustor with the fuel or through the cooling holes as part of the jet. The jet of air would then provide the cooling film for the liner surface as well as a jet of air to mix with the fuel prior to combustion. This increase in mixing performance can be improved further by angling the holes in the circumferential direction to induce a swirl within the combustor.
The present invention provides for improved combustor cooling while enhancing fuel/air mixture in the combustor for a dual-stage, dual-mode low NOx combustor with a dedicated premix chamber.
BRIEF SUMMARY OF THE INVENTION
An improved apparatus and method for mixing fuel and air, while at the same time cooling a gas turbine combustion liner in a can-annular low NOx gas turbine engine that includes a gas turbine combustor having a premixing chamber, a secondary combustion chamber with a venturi, described as a dual-mode, dual-stage combustor. Each gas turbine engine typically has a plurality of combustors.
In accordance with the present invention, each can-annular combustion liner is substantially cylindrical and includes an array of multiple film cooling apertures and dilution cooling apertures disposed in a predetermined array and direction of air flow, resulting in improved cooling performance on the combustion liner, while at the same time providing improved fuel and air mixture in the combustor.
The array of multiple film holes in each can-annular combustion liner includes angling each of the film cooling holes or apertures, both in an axial direction and a circumferential direction. The directionality of air flowing through the angled holes provides for a predetermined flow pattern within the combustion liner that aids in fuel/air mixing. The combustion liner apertures and holes are produced by drilling holes through the combustion liner at a predetermined angular slant in the direction of combustion flow, cold side to hot side. The predetermined strategic slanted or angled aperture is not perpendicular to the combustor wall. A predetermined angle that is in two directions, both axially and circumferentially, is selected to increase the amount of surface area of the combustion liner that is being cooled, while at the same time providing directionality of flow that greatly enhances the mixing of fuel and air. The slanted holes are drilled at a circumferential angle that is preferably in the direction of combustor swirl from the premix chamber. The diameter of each of the holes and the spacing of the holes from each other is sized to maximize the cooling effectiveness of the hole pattern, improve fuel/air mixing, while at the same time not sacrificing the structural integrity of the combustion liner.
The apparatus described in this invention may include the combustor venturi section and air cooling flow as described in U.S. patent application Ser. No. 09/605,765 entitled “Combustion Chamber/Venturi Cooling For A Low NOx Emission Combustor” assigned to the same assignee as the present invention. The combustion liner also contains a dome section, which engages the fuel nozzles and provides another means for introducing air into the combustion process.
It is an object of the present invention to reduce the nitric oxide (NOx) emissions in a gas turbine combustion system by improving fuel/air mixing and lowering flame temperature.
It is another object of the present invention to provide a can-annular low emissions combustor system having combustion liners with apertures or holes for cooling and fuel/air mixing that are slanted axially and circumferentially.
It is yet another object of the present invention to incorporate an improved venturi section that utilizes its cooling air for the combustion process, further reducing polluting emissions.
In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with particular reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 shows a side elevation view in cross section of a typical gas turbine engine.
FIG. 2 shows a side elevation view in cross section of a partial gas turbine engine combustion system that represents the prior art, which utilizes louver cooling.
FIG. 3 shows a side elevation view in cross section of a partial gas turbine engine combustion system that represents the prior art, which utilizes transpiration cooling.
FIG. 4 shows a side elevation view in cross section of a partial gas turbine engine combustion system that represents the prior art, which utilizes impingement cooling.
FIG. 5 shows a perspective view in partial cross section of an annular aircraft gas turbine combustion system that represents prior art, which utilizes film cooling.
FIG. 6 shows a perspective view in partial cross section of an annular aircraft gas combustor that represents prior art, which utilizes film cooling.
FIG. 7 shows a gas turbine combustion liner in perspective view in accordance with the present invention.
FIG. 8 shows a side elevation view in cross section of a partial gas turbine combustion liner in accordance with the present invention.
FIG. 9 shows greater detail of a side elevation view in cross section of a partial gas turbine combustion liner in accordance with the present invention.
FIG. 10 shows a perspective view, partially cut away, of the premix chamber wall having angled film cooling holes in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, an existing gas turbine engine 10 is shown. The engine is comprised of an air inlet 11 , a multi-stage axial compressor 12 , can-annular combustor 13 , which surrounds the aft end of the compressor, combustion transition pieces 14 , which direct combustion discharge gases into the turbine section, a multi-stage axial turbine 15 and exhaust plenum 16 . The turbine 15 , which drives compressor 12 , is connected to the compressor through an axial drive shaft 17 . This drive shaft is also coupled to the generator, which is not shown. The gas turbine engine 10 , which is primarily used for generating electricity draws air into the system through inlet 11 and is then fed into compressor 12 where it passes through multiple stages of fixed and rotating blades. The air, which is now at a much higher pressure is directed into combustion section 13 , where fuel is added and mixed with the air to form the hot gases necessary to turn turbine 15 . The hot gases exit the turbine through multiple transition pieces 14 , which direct the flow into turbine 15 at the proper orientation. The hot gases then pass through multiple stages of fixed and rotating airfoils in turbine 15 , which may or may not be cooled by bleed air drawn off of compressor 12 . The hot gases are then directed from the turbine 15 to exhaust plenum 16 .
Referring now to FIG. 2, a portion of a gas turbine, dual stage combustion chamber 30 is shown in cross section. The combustion liner 31 is shown inside case 36 with cover 35 installed on case 36 . Cover 35 includes multiple fuel nozzles 34 arranged in a circular pattern around the cover as well as a central fuel nozzle of similar configuration. The combustion liner 31 is a dual-stage combustor comprising a premix chamber 38 and a secondary combustion chamber 39 . The two chambers are separated by a venturi 32 with a throat 33 for the purpose of maintaining the flame in a secondary combustion chamber 39 . In this example of prior art, the liner is cooled by air passing through cooling holes 37 and directed downstream by louvers 40 . Louvers provide a rigid surface that results in increased liner structural integrity, while providing a means of directing the cooling air downstream. Louver cooling, also known as rolled ring or splash cooling, bleeds air through small rows of holes 37 in liner wall 31 , and directs it along the liner wall surface by means of an internal deflector, or louver 40 . Drawbacks to this configuration include steep temperature gradients between the metal surrounding the cooling air and the louver edge because the air from the previous row of cooling holes has lost its effectiveness. This thermal problem can produce high stresses in the liner shell resulting in cracking and extreme coating degradation.
A similar combustor, and another form of prior art, is shown in FIG. 3 . Again, a combustion liner 51 is shown for a dual-stage combustor comprising a premix chamber 58 and a secondary combustion chamber 59 . The two chambers are separated by a venturi 52 . All other features are similar to those described in FIG. 2, with the exception of the cooling method for venturi 52 . Louver cooling is utilized in premix chamber 58 by way of cooling apertures 57 and deflectors 61 . The venturi 52 is cooled by transpiration cooling instead of louver cooling as shown in FIG. 2 . In transpiration cooling, air or another cooling fluid passes through a porous structure, such as the venturi walls 63 into the venturi boundary layer on the hot gas path 62 . This allows the venturi inner wall 63 metal temperature to be maintained under that of the gas path 62 . Cooling of venturi 52 is accomplished by the absorption of heat from venturi walls 63 and by altering the boundary layer along venturi flowpath 62 . In order to provide adequate transpiration cooling, material for the venturi walls is typically composed of a porous metal laminate such as Lamilloy. A major drawback to this cooling method is the availability of porous materials required to provide adequate heat transfer and extended durability of these materials.
Referring now to FIG. 4, a similar dual-stage combustion chamber that utilizes impingement cooling is shown. Again, a combustion liner 81 is shown for a dual-stage combustor comprising a premix chamber 86 and a secondary combustion chamber 87 . The two chambers are separated by a venturi 82 with a narrow throat 85 . Other features are similar to those described and detailed in FIGS. 2 and 3. The focus of this example of prior art is the cooling method of venturi 82 . The premix section is cooled with louvers (not shown) as described in FIG. 2 . Venturi 82 is cooled by impingement of air from outside the liner shell along the backside of the venturi flowpath walls 91 and 92 . Cooling air enters the venturi section through apertures 83 in liner 81 . The air then passes through multiple rows of holes 88 and impinges on the backside of venturi gas path walls 91 and 92 . The cooling air then travels downstream through channel 93 and enters the dilution zone 90 of combustion liner 81 as film cooling. Though this cooling method has proven adequate, the major drawback to this configuration is the requirement for double wall construction to create the impingement jets, hence an increased cost and weight, as well as the extreme temperature differences created between the two venturi walls resulting in differential thermal expansion that can lead to buckling. In addition, combustion efficiency is somewhat lower due to the cooling being discharged into the dilution zone aft of the combustion region.
FIG. 5 shows an annular aircraft combustor 100 that utilizes angled film cooling holes for the purpose of improving cooling effectiveness of liner 101 . Multiple fuel nozzles 102 are incorporated in combustion liner 101 . Multiple rows of angled cooling holes 103 are located on the inner and outer liner skin. In addition, larger dilution holes 104 are located further downstream in the liner. A close-up view in cross section of this liner surface is shown in FIG. 6 . For the purpose of more effective liner cooling, an array of cooling holes 103 are drilled a diameter D at an axial angle A relative to the liner skin. The resulting hole is length L. Drilling holes at an angle relative to the flow path provides increased internal surface area for heat removal as well as providing a better layer of film cooling. Holes are spaced a predetermined distance S apart. The holes are also drilled at a tangential angle B to induce a swirl.
The present invention is disclosed in FIGS. 7, 8 , 9 , and 10 . The combustion liner assembly 200 is a dual-stage, dual-mode low nitric oxide (NOx) combustor composed of outer liner 201 , dome cap assembly 204 , and a venturi, which is not visible in FIG. 7 . Liner 201 is held in the combustion system by forward locating tabs 203 and an aft spring seal 202 . The dome cap assembly 204 is held in outer liner 201 by pins 205 . The venturi (not shown in FIG. 7) is held in place in outer liner 201 by two rows of pins 206 . The liner shell 201 has a number of apertures at the forward end for cooling the liner wall and premixing of fuel and air for combustion. The dome cap assembly and venturi are shown in greater detail in FIGS. 8 and 9.
FIG. 8 shows a partial cross-section of the present invention. Again, liner shell 201 is shown with dome cap assembly 204 installed by pins 205 and venturi 212 installed via pins 206 . The dual-stage combustor is comprised of premix chamber 211 and secondary combustion chamber 210 . The dome cap assembly's primary features include openings 213 for multiple fuel nozzles located around the combustor centerline, with an additional opening 214 along the combustor centerline for a secondary fuel nozzle. This center opening 214 includes a swirler 215 . The multiple fuel nozzle receptacles 213 engage a formed dome 216 , which serves as a regulator for controlling the amount of air that enters the combustor. Venturi 212 is a separate component formed of numerous sheet metal pieces with the purpose of forming the secondary combustion chamber 210 and a narrow constriction or throat 219 that maintains the flame in secondary combustion chamber 210 . The venturi has a built-in cooling channel 220 that is formed by two cylindrical inner and outer walls, 221 and 222 , respectively, as well as a forward end 250 and an aft end 251 . The venturi, its cooling circuit, and basic operation are discussed in detail in U.S. patent application Ser. No. 09/605,765, filed Jun. 28, 2000, entitled “Combustion Chamber/Venturi Cooling for a Low NOx Emission Combustor,” assigned to the same assignee as the present invention and incorporated herein by reference.
The basic cooling air flow path is shown in the lower half of FIG. 8, where cooling air flow direction is represented by arrows. The cooling air travels towards the forward end of combustion liner 201 . A predetermined amount of cooling air enters cooling channel 220 through holes 223 in liner 201 . Cooling air travels upstream through channel 220 to the leading edge of venturi 212 and exits the venturi through matched holes 224 in the venturi outer skin and liner 201 . The cooling air, which has been preheated as a result of cooling the venturi inner walls 221 , 228 , and 229 , enters an annular cavity 226 formed by a belly band 225 around liner 201 . Due to the pressure loss along cooling channel 220 , additional cooling air is supplied to annular cavity 226 by resupply holes 230 . The cooling air, now at a higher pressure is directed out of annular cavity 226 through multiple rows of angled holes 227 . This air is then premixed with the fuel and air in premix chamber 211 and used in the combustion process in secondary combustion chamber 210 .
The remainder of the cooling air that is not utilized in cooling venturi 212 is carried upstream to premix chamber 211 . For clarity purposes, this region is enlarged and shown in FIG. 9 . Air used for effusion cooling is channeled into premix chamber 211 through multiple rows of angled film cooling holes 217 where it forms a cooling film along liner shell 201 and due to its high velocity, penetrates the boundary layer to mix with the previously discharged fuel and air prior to combustion. Cooling holes 217 are angled such that air entering the combustor from the holes is directed towards the combustion chamber. These angled film cooling holes may also be angled tangentially with respect to the combustor centerline to impart a swirling component to the cooling air as explained below (see FIG. 10 ). Additional air is introduced to the premix chamber through dilution holes 218 for mixing with the upstream fuel and air. The remaining air travels upstream to the forward end of liner 201 and is introduced through one of four regions. Air can enter premix zone 211 through multiple rows of angled film cooling holes 232 in dome plate 216 . These holes may be angled in a tangential direction relative to the combustor centerline to impart swirl in the cooling air. A portion of the air dedicated for dome plate 216 is used to cool the nozzle tubes 234 by way of impingement cooling. Cooling air impinges upon the backside of nozzle tubes 234 through impingement holes 233 and is then directed downstream into premix chamber 211 . The second air route is through nozzle tube 234 located within aperture 213 . The air passing through this region travels through the fuel nozzle air swirler (not shown) where it is premixed with fuel prior to entering premix chamber 211 . The third passage for air entering the combustion system through the dome cap assembly is through an inner substantially cylindrical tube 214 and swirler 215 , which is located within inner tube 214 . The swirler is comprised of inner and outer cylindrical tubes 237 and 238 , respectively. Joining these concentric tubes is an array of angled vanes 239 . This air will mix with the fuel and air of the secondary fuel nozzle (not shown) and exit into the secondary combustion chamber 210 . The fourth method and structure for introducing air into the premix chamber is through cavity 235 formed by inner tube 214 and an outer tube 236 , which are co-axial. Air exits channel 235 through multiple rows of angled film cooling holes 217 in outer center tube 236 or through an aft swirler 231 , which is co-axial to swirler 215 , and discharges the air into secondary combustion chamber 210 . Again, the angled holes 217 direct cooling air towards the combustion chamber and may be angled circumferentially as well, depending upon the application.
The premix chamber liner shell 201 cooling hole pattern utilized on the present invention is shown in greater detail in a cross-sectional view of premix chamber liner shell 201 as in FIG. 10 . The cooling holes 217 (all the holes shown in FIG. 10 except hole 218 ) are angled both towards the combustion chamber and circumferentially in order to increase cooling surface area and to induce swirl within the premix chamber, hence improving fuel and air mixing, which will result in lower emissions. Typical combustor liner wall thickness for effusion cooling is thicker than combustors shown in the prior art, with wall thickness at a minimum of 0.0625″, ranging up to 0.25″. The liner wall is laser drilled with a specified pattern of cooling holes 217 and dilution holes 218 . Typical effusion cooling hole diameters EH can range from 0.015″ to 0.125″, while dilution hole DH diameters can range from 0.4″ to 1.5″ as well. Diffusion hole 218 is typically drilled normal to liner shell 201 , while effusion holes 217 are drilled at an angle A relative to the premix chamber centerline axis, where angle A can range from 15 deg to 60 deg from centerline. Drilling these holes at such an angle will result in cooling hole length L, which is a function of angle A. In order to induce swirl within the combustor, which will improve overall mixing of fuel and air, the cooling holes are also drilled at a circumferential angle B, which typically ranges from 15-60 degrees. The cooling holes are spaced apart a circumferential distance C and an axial distance S. These distances are specifically calculated depending upon the application and operating conditions to ensure that the proper amount of cooling air is applied to liner shell 201 for cooling purposes.
Operation of the dual-stage, dual-mode combustor disclosed in the present invention is similar to those of similar configuration where ignition is established in the primary zone, or premix chamber, first. Upon confirmation of a steady flame in primary or premix zone 211 , the fuel circuits are opened to the secondary fuel system (not shown) located within center body 214 and flame is established in secondary combustion chamber 210 , aft of venturi throat 219 . Upon confirmation of flame in the secondary combustion chamber 210 , the fuel supply is gradually reduced to the primary fuel nozzles in nozzle tubes 234 until the flame is extinguished, while fuel supply to the secondary fuel system (not shown) is increased in order to transfer all flame to the secondary combustion chamber 210 . Fuel supply is gradually increased to the primary fuel nozzles (not shown) to create a premix of fuel and air in premix chamber 211 while fuel to the secondary system is decreased. This premix fuel and air in the primary premix chamber travels downstream to the secondary combustion chamber where ignition occurs.
The benefits to the present invention are numerous over similar hardware configurations. The angled cooling holes in premix chamber liner 201 provide for improving the film cooling effectiveness along the liner skin as well as allowing the cooling air to penetrate the gas path and mix more completely with the fuel within the premix chamber. This configuration is advantageous for an industrial application where increased weight from thicker liner walls is not a primary concern but improved emission is critical. The angled cooling holes by design do not require as much cooling air, so air originally designated for liner cooling can now be introduced further upstream in the premixing process. This extra air introduced further upstream in the liner pushes the fuel/air ratio lower and lowers the flame temperature by allowing for a longer mixing period, hence more complete mixing. These are both key elements that lower NOx levels. A further element to lower NOx emissions of the liner is to introduce the venturi cooling air into the combustion process, which will further reduce the fuel to air ratio and flame temperature, again lowering the resulting NOx levels. This can be accomplished by utilizing the improvements disclosed in U.S. patent application Ser. No. 09/605,765 entitled “Combustion Chamber/Venturi Cooling for a Low NOx Emission Combustor” assigned to the same assignee as the present invention. By reintroducing the cooling air from the venturi into the combustion process in combination with improving the upstream mixing pattern and increasing air flow into the premixing process, overall NOx emissions are substantially reduced.
The instant invention has been shown and described herein in what is considered to be the most practical and preferred embodiment. It is recognized, however, that departures may be made therefrom within the scope of the invention and that obvious modifications will occur to a person skilled in the art. | An improved dual-stage, dual-mode turbine combustor capable of reducing nitric oxide (NOx) emissions is disclosed. This can-annular combustor utilizes multiple, single wall sheet metal combustor liners, generally annular in shape, and each liner having multiple hole film cooling means, which includes at least one pattern of small, closely spaced film cooling holes angled sharply in the downstream direction and various circumferential angles for improved liner cooling and improved fuel/air mixing within the liner, resulting in lower NOx emissions. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 60/717,997 filed Sep. 16, 2005, which is incorporated by reference as if fully set forth.
FIELD OF INVENTION
[0002] The present invention is related to wireless communication systems. More particularly, the present invention is related to a method and apparatus for managing power during a discontinuous reception (DRX) mode.
BACKGROUND
[0003] Reducing power consumption is one of the most important challenges when designing the wireless transmit/receive units (WTRUs). Increased bandwidth, higher data rates and multimedia user interfaces result in higher power demands for new WTRUs as compared to previous generations of WTRUs.
[0004] The DRX mode is intended to identify periods of relative inactivity of the WTRU, which provides opportunities to conserve battery power by powering down various on-board components in the WTRU. The WTRU is informed of occasions when the WTRU must wake up to receive transport information.
[0005] The WTRU radio resource control (RRC) has a connected mode and an idle mode. The connected mode includes an active connected mode and an inactive connected mode. In the connected mode, the WTRU RRC has four states: CELL_DCH, CELL_FACH, CELL_PCH, and URA_PCH. The CELL_DCH and the CELL_FACH states take place only in the active connected mode, and the CELL_PCH and the URA_PCH states take place only in the inactive connected mode. The DRX mode takes place in the inactive connected mode, (CELL_PCH, URA_PCH states), and in the idle mode.
[0006] The basic difference between DRX in the idle mode and the connected mode is that, in the idle mode, it is the core network (CN) that controls the DRX cycle; whereas in the inactive connected mode, it is the universal mobile telecommunication system (UMTS) terrestrial radio access network (UTRAN) that controls the DRX cycle.
[0007] During DRX mode, the WTRU must wake up on Paging Occasions (POs) as directed by the RRC, based on system information settings. A PO indicates the beginning of a paging block. The RRC is responsible for scheduling the time, the duration and on which channel the physical layer of the WTRU must listen to.
SUMMARY
[0008] The present invention is related to a method and apparatus for managing power during DRX mode. During the DRX mode, the WTRU enters into a sleep state and periodically wakes up for processing paging blocks for detecting a paging indication for the WTRU and a corresponding paging message. If the WTRU is paged, the WTRU terminates the DRX mode. If the WTRU is not paged, the WTRU reenters the sleep state. For power management during the DRX mode in the WTRU, a synchronization update period is defined. The synchronization update period is a period for performing automatic frequency correction (AFC) and/or frame time correction (FTC).
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] A more detailed understanding of the invention may be had from the following description, given by way of example and to be understood in conjunction with the accompanying drawings wherein:
[0010] FIG. 1 is a diagram of time slot level timing requirements for DRX mode in accordance with the present invention;
[0011] FIG. 2 shows inputs and outputs for an AFC algorithm;
[0012] FIG. 3 is a block diagram of a closed loop AFC;
[0013] FIG. 4 shows inputs and outputs for FTC operation; and
[0014] FIG. 5 is a block diagram showing relationship between an FTC unit and a timing manager in a WTRU.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] Hereafter, the terminology “WTRU” includes but is not limited to a user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a pager, or any other type of device capable of operating in a wireless environment.
[0016] The features of the present invention may be incorporated into an integrated circuit (IC) or be configured in a circuit comprising a multitude of interconnecting components.
[0017] Hereinafter, the present invention will be explained with reference to UMTS time division duplex (TDD) systems. However, the present invention is applicable to any wireless communication systems including, but not limited to, UMTS frequency division duplex (FDD), TD-SCDMA, CDMA 2000, or the like.
[0018] The present invention provides an efficient power management method for the physical layer of a WTRU. In accordance with the present invention, AFC and FTC are performed during DRX mode, and a sleep timer is preferably provided for synchronization during DRX mode. The WTRU updates its frame synchronization and timing synchronization periodically during DRX mode to be able to successfully read paging indicators (PIs) and perform cell reselection measurements. Periodic DRX activities for the physical layer include cell reselection and the related measurements, monitoring PIs and maintaining frame and timing synchronization.
[0019] Five different physical layer states are defined as follows: an active connected state, an inactive connected state, a sleep state, a PI reading state, and a synchronization update state. During the active connected state, almost all components are powered on and normal operation for communication is performed. During the inactive connected state, some components are powered down. During the sleep state, most of the components are powered down and the WTRU neither reads the paging block nor updates the frame or timing synchronization. Functionality required during the sleep state is limited to monitoring clock, detection of user activity and interface with debug equipment, and activation of triggers to wake-up various on-board components in sequence. During the PI reading state, the WTRU wakes up from the sleep state to read the related PI via a paging indicator channel (PICH) in each paging block. If the WTRU detects that it is paged through the related PI in the PICH, the WTRU reads a paging channel (PCH) to access the paging message. Otherwise, the WTRU returns to the sleep state. During the synchronization update state, synchronization updating is performed, AFC and FTC are run and TCXO control voltage and frame synchronization are updated.
[0020] FIG. 1 is a diagram of time slot level timing requirements for DRX mode in accordance with the present invention. A frame offset 102 is generated by the FTC for frame synchronization, which will be explained hereinafter. During DRX mode, the WTRU may be in the sleep state, in the PI reading state or in the synchronization update state. The WTRU enters the PI reading state sometime in the paging block 104 and enters the synchronization update state in the sync update block 106 . The WTRU is in the sleep state in the remaining blocks 108 .
[0021] A DRX cycle length is the time difference between two POs for a specific WTRU. In UMTS TDD, one PO corresponds to one paging block. Therefore, the DRX cycle length is the time difference between two paging blocks 104 . A paging block 104 comprises a PICH block 112 , a gap period 114 and a PCH block 116 . The PICH block 112 comprises 2 or 4 frames of PIs. The gap period 114 comprises 2, 4, or 8 frames where physical resources can be used by other channels. The PCH block 116 comprises 2 to 16 frames of paging messages for one to eight paging groups. For the idle mode, the allowed DRX cycle lengths are 0.64, 1.28, 2.56 and 5.12 seconds. For the inactive connected mode, the allowed DRX cycle lengths are 0.08, 0.16, 0.32, 0.64, 1.28, 2.56 and 5.12 seconds.
[0022] The synchronization update period is a period between two consecutive sync update blocks 106 . The synchronization update period is preferably set to 256 or 512 frames depending on the DRX cycle length. The sync update block 106 preferably, but not necessarily, comprises 21 frames. The first frame 122 1 is for TCXO settle time and every fifth frame 124 1 - 124 4 starting from the second frame is processed for AFC and FTC, which will be explained in detail hereinafter. The TCXO settle frames 122 2 - 122 5 are also provided before each frame 124 1 - 124 4 to be processed. During the intervening frames 126 1 - 126 4 , each of which is three frames, the WTRU is powered is down. Therefore, during the synchronization update block, the WTRU is periodically powered up and powered down for AFC and FTC. If the DRX cycle length is 16 frames, the sync update block 106 may overlap one paging block 104 , and if the DRX cycle length is 8 frames, the sync update block 106 may overlap two paging blocks 104 . In these cases, regular paging procedures and synchronization update activities are implemented in parallel.
[0023] AFC operation will now be described. Since a specific implementation of AFC is not within the scope of the present invention, AFC operation will only be briefly described. FIG. 2 shows inputs and outputs for an AFC unit 200 which implements an AFC algorithm. A received signal 202 (preferably 2× over-sampled), an odd/even frame indicator 204 , a cell parameter 206 , RF carrier frequency 208 and initial voltage controlled oscillator (VCO) digital-to-analog converter (DAC) control voltage 210 are input for the AFC unit 200 based upon a user defined value or a previously stored value. The AFC unit 200 outputs are a control voltage to the VCO 212 , an estimated frequency error 214 and a convergence indicator 216 . The operating frequency of the VCO is determined by the control voltage 212 . The convergence indicator 226 indicates that the AFC algorithm reaches a steady state.
[0024] FIG. 3 is a block diagram of a closed loop AFC unit 300 . Received signals 302 are mixed with signals 308 generated by the VCO 306 by a multiplier 304 to be converted to baseband signals 310 . The baseband signals 310 are converted to a digital data 314 by an analog-to-digital converter (ADC) 312 . The digital data is processed by a raised root cosine (RRC) filter 316 and fed into a frequency estimation block 318 . A frequency error is computed by the frequency estimation block 318 and a cell search/FTC block 320 and the estimated frequency error 214 is sent to a loop filter that generates the correction voltage for the VCO 306 . This correction voltage is converted to a digital signal by a digital-to-analog converter (DAC) 324 and filtered by a low pass filter (LPF) 326 and drives the measured frequency error to zero in a steady state. Baseband transmit data 332 is converted to an analog data 335 by a DAC 334 and multiplied with a VCO output 309 by a multiplier 336 for transmission.
[0025] During the active connected state, AFC is running as normal. Before entering into the DRX mode, the last value of the VCO DAC register is saved in memory. This value is used during the DRX mode until the next VCO value is available from synchronization update. During the sleep state and the inactive connected state, since there is no data reception, AFC is shut down when the processing from the previous active timeslots is completed. During the PI reading state, AFC is running and the P-CCPCH beacon is read during each frame in the paging block. During the synchronization update state, AFC runs using only one midamble per frequency update and with special timing as shown in FIG. 1 . However, during the PI reading period, the number of midambles processed per frame depends on the frequency error, which is similar to the AFC operation during the active connected mode.
[0026] There are two reasons for running AFC during the DRX mode. The first reason is the effect of WTRU motion on the acquired sampling period of the WTRU, which is controlled by the VCO 306 . If the speed of the WTRU changes during the sleep interval, the difference in speed of the WTRU before and during the sleep cycle will look like an extra drift rate change in the VCO 306 . As an example, assume that the WTRU is not moving before the DRX cycle. Afterwards, the WTRU goes into the DRX mode. Also assume that, when the WTRU goes into a synchronization update state during DRX mode, the speed of the WTRU becomes 120 km/h, which is the maximum speed from WG4 test cases. As a result, the difference in speed is Vd=120 km/h. This speed corresponds to Drift ppm =(vd/c)×1.0e6=0.11 ppm drift, where c is the speed of light. However, this drift is extremely unlikely since the maximum time difference between the beginning of a DRX cycle and the next synchronization update may be approximately five seconds. Since this number is not the driving requirement for the design, it can be kept as described hereinbefore. Additionally, a possibility of an extra drift rate change due to turning off the VCO during the DRX period requires a VCO control voltage update during DRX.
[0027] To correct for this possible change in drift rate, the WTRU wakes up at the beginning of the sync update block and performs AFC and FTC. Since AFC needs to update the VCO control voltage, all the physical layer components preceding AFC should be working as well. This includes a root raised cosine (RRC) filter, an automatic gain control (AGC), and a gain scaler.
[0028] At the beginning of the sleep period of a DRX cycle, the receiver and the TCXO are shut down. The radio must be powered up before every synchronization update. The TCXO and phase locked loop (PLL) joint power up time is around 5 msec. The synthesizer and other hardware components require much less time to power up. Therefore, the radio should preferably power-up at least 5 msec before the first frame necessary to process, (i.e., paging blocks and frames for AFC and FTC). This is a radio power-up time, (which is shown as “TCXO settle time” before each paging block and during the sync update block in FIG. 1 ). The radio power-up time may be designated to a start of a given frame, (i.e., one frame earlier than the start of each paging block or first P-CCPCH beacon frame to be read).
[0029] The synchronization update block preferably comprises 21 frames. The first frame (and every fifth frame thereafter) is for TCXO settling time as explained hereinbefore. A beacon, (i.e., P-CCPCH signal), is then acquired every fifth frame starting from the second frame of the synchronization update block. The midamble part of the first P-CCPCH timeslot is extracted and passed to the frequency estimation unit for new frequency error estimation. After reading the beacon, the power is shut down and then up again at the next TCXO settle time for reading the next beacon. This is repeated four times during the synchronization update state.
[0030] Using beacons separated in time, instead of using four beacons from consecutive frames, increases robustness of frame synchronization under slow fading conditions. The midambles processed during the synchronization update state are summarized in Table 1. It should be noted that the specific numerical selections in the foregoing paragraphs and Table 1, (and throughout this document), are provided as an example, not as a limitation, and any other numbers may be used alternatively.
TABLE 1 synchro- nization Radio wake DRX cycle update P-CCPCH frame up frame length period numbers used number Next PO 8, 16, 32, 64, 256 256N- 20 256N - 21 256N 128, 256 256N- 15 256N- 10 256N- 5 512 512 512N- 20 512N - 21 512N 512N- 15 512N- 10 512N- 5
[0031] The timing of these frames for AFC is also used for FTC. Since AFC has its own multipath search window, AFC can work without waiting for a frame synchronization update. Therefore, AFC and FTC may run at the same time. Since both AFC and FTC only use P-CCPCH midambles, it is computationally easier to run them at the same time. Therefore, AFC simply borrows this timing schedule from FTC.
[0032] The synchronization update rate preferably depends on the DRX cycle length as summarized in Table 1. For DRX cycle lengths up to 256 frames, the synchronization update period is 256 frames and for the DRX cycle length of 512 frames, the synchronization update period is 512 frames.
[0033] The midamble processing and frequency update for AFC during DRX mode is the same as in the connected mode, with the exception of the number of midambles used per frequency update. In the connected mode, the number of midambles per frequency update depends on the previous frequency error as described hereinbefore. In the synchronization update state, only one midamble per update is used, independent of the frequency error.
[0034] During paging blocks, AFC runs only if it has not converged during the preceding sync update period, which will be described in detail hereinafter. In each PO, the WTRU wakes up from the sleeping state and checks for a PI. As soon as the WTRU decides that it is not being paged, it goes back to the sleep state by powering down the receiver and the TCXO. If the WTRU is being paged, the DRX operation is discontinued. If AFC convergence is declared by the convergence indicator at the start of a paging block following the sync update block, AFC does not run until the next sync update block. For paging blocks not succeeding a sync update block, AFC does not run at all.
[0035] If AFC convergence is not declared at the end of the sync update block, AFC performs one frequency update from every P-CCPCH (every frame) during the upcoming paging block. This continues until either AFC has converged or the paging block is over, which ever happens earlier. The convergence is checked after each frequency update. After AFC convergence is declared, there is no need to run AFC further until the next sync update block. If the convergence is not declared by the end of the paging block following the sync update block, AFC continues to run in the upcoming sleep periods.
[0036] AFC does not operate during DRX sleep periods, except for the case of non-convergence at the end of a paging block following a sync update block as described hereinbefore. If AFC has converged by the start of a sleep period, the receiver and the TCXO is shutdown. If AFC has not converged at the start of a sleep period, the TCXO remains ON and AFC operates as it does in the connected mode. If convergence is declared during the sleep period, the TCXO and the receiver are shut down for the remainder of the sleep period if the next wake-up time is at least a frame apart from convergence declaration time.
[0037] FTC operation will be described hereinafter. Timing within the WTRU should be synchronous to the received signal frame boundaries. Frame synchronization of the WTRU is based on the location of the first significant path (FSP) in the delay spread of the multipath channel. Although the initial cell search performs the initial frame synchronization, there is still a need to maintain frame synchronization to compensate for WTRU motion, shadowing and possible error in the initial cell search. The FTC starts running after initial cell search is completed and AFC comes into a steady state.
[0038] FIG. 4 shows inputs and outputs for an FTC operation and FIG. 5 is a block diagram showing the relationship between an FTC unit 502 and a timing manager 506 in a WTRU. Since a specific implementation of FTC is not within the scope of the present invention, FTC operation will only be briefly described hereinafter. As shown in FIG. 4 , broadcast channel (BCH) received signals 402 , (preferably 2× over-sampled), a system frame number (SFN) and an even/odd indicator 404 , a BCH transmit diversity indicator 406 and a cell ID 408 are inputs for an FTC unit 400 which implements an FTC algorithm. The FTC unit 400 generates a frame sync correction signal 410 as an output. Referring to FIG. 5 , an FTC unit 502 finds the position of the FSP by performing correlations of the received BCH midamble(s) over different time lags. After accumulating processing results multiple times, the FTC unit 502 finds the most significant path (MSP) and verifies the validity of the MSP, (i.e., determines if a signal-to-noise ratio (SNR) of the outputs are strong enough to assume that a valid path has been identified). If the MSP value is above a threshold, MSP Valid is ON, otherwise MSP Valid is OFF. If MSP Valid is ON, the FTC unit 502 finds the FSP position by checking each accumulated results above the threshold.
[0039] The FSP processing unit 504 receives the FSP location and MSP Valid signal form the FTC unit 502 and sends the Frame Sync Correction signal to the timing manager 506 . If MSP Valid is ON, Frame Sync Correction is computed as follows:
Frame Sync Correction=FSP position−Frame Offset.
The constant Frame Offset is set to five chips currently. This is due to the assumption that the maximum delay spread considered is up to 47 chips from the WG4 test cases. For a channel estimate vector of length 57 chips, this leaves a room of 10 chips. Five chips in each direction are reserved for the purpose of possible drifts of frame sync in either direction. Therefore, the WTRU always sees the FSP in the channel estimator output without any frame synchronization correction up to five chips drift. Therefore, there is no update necessary for short DRX cycles. This prevents unnecessary wake ups of WTRUs and helps conserve battery power. If the magnitude of Frame Sync Correction is greater than S max , it is hard limited to ±S max . If MSP Valid is OFF, Frame Sync Correction is set to zero.
[0040] During the active connected state, FTC is running. The FTC algorithm continuously adjusts the frame synchronization, (i.e., the frame beginning by controlling the timing manager). The last frame synchronization update in the active connected mode should be used during the DRX cycles until the next update in a synchronization update state. During the sleep state and the inactive connected state, since there is no data reception, FTC is shut down if all the processing from the preceding frames is completed. If all the processing from the preceding frame is not completed, FTC may run in the sleep state, which will be explained hereinafter. During the PI reading state, FTC may be running and P-CCPCH beacon may be read during each frame in the paging block. During the synchronization update state, FTC runs in a different way than in the active connected state.
[0041] The FTC tracks frame synchronization under WTRU motion, TCXO drift due to a possible AFC bias and RTC drift. FTC corrects the shifts of the frame beginning in either direction. Since a frame beginning is referenced to an FSP, FTC searches and locates the FSP. Whenever FTC updates the FSP location, the FTC re-calculates the frame synchronization. The FTC is also scheduled during the synchronization update state, and the timing of the frame synchronization update and VCO control voltage update is exactly the same as shown in Table 1.
[0042] At the beginning of the sleep period of a DRX cycle, the receiver and the TCXO are shut down. Every synchronization update block, the radio is powered up before the first frame to be read. During sync update blocks, FTC makes one frequency update. The WTRU preferably reads the midambles of four P-CCPCHs, each separated by five frames, as shown in FIG. 1 . FTC makes a frame sync update after processing four midambles.
[0043] At each PO, (i.e., during the PI reading state), the WTRU wakes up from the sleep state and checks the PI. As soon as the WTRU decides that it is not being paged, it goes back to the sleep state by powering down the receiver and the TCXO. If the WTRU is paged, the DRX operation is discontinued. If MSP Valid is declared by the FTC at the start of a paging block following the sync update block, there is no FTC operation during the paging block. If the MSP Valid is not declared by the FTC at the start of the paging block followed by the synchronization update block, the FTC continues to work during the paging block until it finds an FSP update with MSP Valid declared. During this extended time, FTC uses four consecutive frames instead of separated ones. FTC makes FSP detection from four consecutive frames until it finds one update with MSP Valid. This continues until the paging block is over.
[0044] FTC does not operate during the sleep state, except for the case that MSP Valid is not declared at the end of a paging block. If MSP Valid is declared by the start of the sleep period, the receiver and the TCXO are shutdown. If MSP Valid is not declared at the start of the sleep period, the TCXO remains ON and FTC operates on four consecutive frames. If MSP Valid is declared during the sleep period, the TCXO and the receiver are shut down for the remainder of the sleep period if the next wake-up time has not yet occurred.
[0045] Although the features and elements of the present invention are described in the preferred embodiments in particular combinations, each feature or element can be used alone without the other features and elements of the preferred embodiments or in various combinations with or without other features and elements of the present invention. | A method and apparatus for managing power during discontinuous reception (DRX) mode are disclosed. A DRX mode is defined for a wireless transmit/receive unit (WTRU) for reducing power consumption of the WTRU. During the DRX mode, the WTRU enters into a sleep state and periodically wakes up for processing paging blocks for detecting a paging indication for the WTRU and a corresponding paging message. If the WTRU is paged the WTRU terminates the DRX mode. If the WTRU is not paged, the WTRU reenters the sleep state. For power management during the DRX mode, a synchronization update period is defined. The synchronization update period is a period for performing automatic frequency correction and/or frame time correction. | 8 |
BACKGROUND
[0001] The invention relates to a mule with at least one strap for securing the foot on the mule.
[0002] The word mule is to be understood as meaning a lady's shoe, a particularly fashionable shoe. The mule has a main body extending under the foot. This main body is generally made of plastic or wood. Similar materials are likewise provided. The main body thus comprises a seat for the foot, and a walking surface facing away from the foot. This walking surface serves as a sole and comes into contact with the ground on which the person wearing the mule is walking. The seat for the foot is adapted at least approximately to the contour of the foot, in such a way that the foot, including the toes, is received in its entirety by the planar design of the main body. The instep is covered only by a strap. The rest of the instep and also the heel are free.
[0003] The walking surface of the main body is generally designed in three parts. The front part, directed toward the toes, is designed as a sole surface, and the part assigned to the heel area is designed as a heel surface. The area between the sole surface and the heel surface is designed in such a way that it does not touch the ground when the shoe is set down.
[0004] The mule can be without a heel or can have a low or a high heel.
[0005] As has already been stated above, the mule comprises at least one strap which extends, transversely with respect to the longitudinal extent, from one side of the main body of the mule to the other side of the main body of the mule. The mule can be decorated with ornamental elements. In particular the strap can be fashioned with beads, bows, leather bands or gems to give a simply stylish, plain or even grand appearance.
[0006] Shaped like a strip or band extending across the instep of the foot, the strap holds the mule on the foot, so that no further holding device, for example a heel strap, is needed. The strap has a convex shape, such that it is able to bear, both longitudinally and also transversely, on the instep, which is likewise convex, and it thus provides a comfortable feel.
[0007] The mule is distinguished especially by the comfort it provides. There are mules that are open at the toes and ones that are closed, while the heel is generally always free. The mule is preferably worn with summer clothing, short dresses or short trousers.
[0008] Mules have been worn by women since the 15th century in Europe, mainly by housewives while doing housework. The end of the 20th century saw a fashion trend in which a large number of different forms of mules were developed, either with different materials or different colors and different creative designs.
[0009] Along with the shape of the main body of the mule on which the foot is placed, another style feature is the strap. The latter is chosen such that it matches the clothes that are to be worn.
[0010] The strap is either secured on the side faces of the main body by nails or screws or is adhesively bonded thereto. In order to ensure sufficient strength, the free end of the strap is inserted in a slit formation and secured there. Alternatively, the strap can also be secured directly on the side face of the main body.
[0011] The consumer purchases a mule that is to her taste and that matches her clothing. Therefore, on account of the design of the strap and the design of the mule, it is necessary to own a number of different mules to ensure that they match the clothes.
[0012] A further disadvantage is that, if the straps are provided with corresponding decorations and these decorations are damaged, the consumer has to purchase a new pair of mules.
[0013] If the straps bursts, the consumer is forced either to get the mule repaired or to buy new mules.
[0014] WO2006/020215 A2 discloses a sandal consisting of a main body, wherein exchangeable straps are arranged on the main body and, when the sandal is being worn, at least partially enclose the foot. The straps have hook-shaped elements, which engage in eyelet-like formations on the side of the main body. In order to detach the straps from the main body, the hook-like elements are moved in a direction such that they can disengage from the eyelets.
[0015] In order to bring about this detachment, an actuation element is provided on the heel side or rear side of the sandal and is coupled to the eyelet-like formations. In this way, the eyelet-like element can be separated from the hook-like element by a kind of cable pull.
[0016] US 2006/0080813 A1 likewise discloses a mule that has exchangeable straps. At their free ends, the straps have fixing elements which, on the side facing the foot, engage in corresponding recesses and latch therein. In order to remove a strap, it is necessary to operate the respective free end of the straps via an actuation element, so as to release the snap-fit connection between the fixing element and the fixing device.
[0017] The design is very complex, since the device has to be arranged at each free end of the straps. For this purpose, it is necessary to work the main body, both on the side facing the foot and also on the front face, in order to introduce the fixing device into the main body. The actuation element is very small, such that it can only be operated using an additional object.
[0018] WO 2008/030479 likewise discloses a sandal that has exchangeable straps. The free ends of the exchangeable straps have fixing elements which can be preferably screwed into the respective fixing device in the area of the main body. Alternatively, provision is also made for magnetic elements to be arranged in the respective fixing devices, which magnetic elements provide a force-fit connection between the fixing device and the fixing elements.
[0019] This design is also very complex, since the fixing devices have to be formed exactly at the corresponding locations inside the main body. To do this, it is necessary for the main body to be worked very precisely on the side facing toward the foot. Moreover, very high forces act in the area of the foot, such that a magnetic closure alone is not sufficient. In order to counteract this, provision is additionally made to form a bayonet catch. However, this bayonet catch has the disadvantage that the strap first has to be turned through at least 45 degrees before it reaches the correct position.
[0020] A sandal designed in the manner of a flip-flop is known from US 2010/0132223 A1. The free ends of the respective straps have, as fixing elements, clip-like connection elements that cooperate with fixing devices, which are also designed like clips and are present in the main body. In order to detach the strap, each free end has to be suitably operated. To ensure that the clip-like connections do not adversely affect the wearing comfort, they are made very small. This in turn has the disadvantage that they are extremely difficult to operate. In addition, the link to the respective clip elements offers a predetermined breaking point, such that increased wear is present.
[0021] U.S. Pat. No. 6,430,846 discloses a sandal that likewise has exchangeable straps, of which the free ends are designed with fixing elements. These fixing elements are very broad, such that they interact with fixing devices arranged inside the main body. The interaction is obtained by providing openings on the side facing toward the foot, into which openings the fixing elements can be inserted. Latching elements of the fixing device ensure that the straps are held firmly on the main body. Actuation elements are provided at the end face which disengage the latch. The actuation for this design of sandals with detachable straps is designed like a push button at the end face. Here too, however, there is the disadvantage that it is complicated to operate each free end with the actuation. There is a danger that if one side is suitably detached and one turns to the other side, the one side latches again. In addition, the openings directed toward the foot, for the purpose of receiving the fixing elements, offer a very large space for dirt. Moreover, they are arranged in the visible area, and this therefore already represents a disadvantage for esthetic reasons.
[0022] DE 10 150 792 A1 counters this disadvantage. Here, a shoe is provided with a main body that likewise has exchangeable straps. However, the straps are not insertable on the top of the main body facing toward the foot, but instead at the front. For this purpose, a recess is provided on each side, in which recess a pin element is arranged which extends in the longitudinal direction of the shoe and of which the free ends are designed like springs and can be brought into engagement with fixing elements. The spring pin designs, of the kind also known for fastening watch straps for example, are intended to serve to fix the straps. However, this design has the disadvantage that the forces that act in mules of this kind cannot be taken up by the pin-like designs. Moreover, detaching the straps proves very difficult, since a very small tool is also needed in order to disengage the pins from the fixing aids.
[0023] The problem addressed by the invention is to make available a mule having detachable straps, of which the stylish appearance can be adapted by the consumer to the corresponding needs of the consumer, wherein handling is intended to be simple, such that the straps can be detached by simple operation.
SUMMARY
[0024] The problem is solved by the features of claim 1 .
[0025] The basic concept of the invention is that the strap is connected to the main body of the mule by a detachable form fit and/or force fit or only by a detachable force fit.
[0026] To provide such a force fit, a fixing device that detachably fixes the free ends of the strap at least indirectly on or in the main body is arranged inside the main body or on the main body. By actuation of an actuation element, which is part of the fixing device, the force fit is canceled, and the strap fixed per se on the main body can be removed from the main body and can be replaced by a new strap which, for example, meets the fashion style of the user.
[0027] In one development, a form fit is also provided in addition to the force fit. The forces that occur in the area of the instep, held by the strap, while walking and running are great, and therefore a form fit is additionally provided for a preferably optimal design of the force fit. For this purpose, provision is made that fixing elements are arranged on the free ends of the strap, in such a way that these engage recesses provided in the main body and thus establish a form fit at least indirectly between the strap and the main body. The force-fit means or fixing means hold the fixing element detachably on the main body.
[0028] Different configurations may be proposed for the above-described force fit.
[0029] Firstly, provision is made that the detachable force fit is made available, regardless of whether a form fit is provided or not, by laterally arranged means, for example push buttons, magnets or similarly or identically acting means. Secondly, provision can be made that the fixing device is arranged inside the main body and can thus be designed in various ways. This has the basic function of receiving a fixing element, which is arranged on the strap, with a force fit but also detachably. By actuating an actuation element, for example a button, a rotary knob or the like, the force-fit connection can be released, such that the strap can be exchanged after it has been guided by hand out of the connection. A combination of force fit and form fit supports the holding force of the strap on the main body.
[0030] The force fit itself can be effected through one or more clamp elements. These clamp elements can be spring-loaded such that, when the force-fit means arranged on the free ends of the strap is pressed in, an independent locking takes place inside the main body. By actuating a trigger mechanism, the lock is freed again. This trigger mechanism can be arranged both on the underside and also on the top of the main body. A lateral arrangement is likewise conceivable. Provision is preferably made that this trigger mechanism is arranged on the underside of the main body between the sole surface and the heel surface of the mule. Triggering can be effected by a rotation of an adjustment element, wherein the rotation movement is either to be carried out using a special key, or the adjustment element has a slit, such that the rotation movement can be effected by an inserted coin (in place of a screwdriver).
[0031] The release can also take place only indirectly. For this purpose, provision is preferably made that by means of a magnet, which is held on the underside the sole side of the mule facing toward the street, the force-fit connection between the fixing elements and the fixing device is releasable. For this purpose, provision is made that the locking or also the undercut or engagement behind of fixing elements and fixing device can be released by a single for example lifting movement, in such a way that both parts are disengaged. On account of the pretensioning that results from the material of the strap, the two fixing elements migrate away from the main body and are thus released in a very simple manner from the main body.
[0032] In a particular development, provision can be made that the fixing device is made available as a subassembly, such that it can be arranged in a simple way as a unit on a specially designed main body which provides the corresponding recess. In this way, the main body can be produced and made available separately from the means for establishing the force fit or form fit. When the two components are made ready, they can be simply joined together by adhesive bonding or screwing. It is also conceivable that the subassembly is made of plastic and the main body is made of wood. Other materials are also provided. The formations which in particular effect the operation of the release of the strap from the main body on the underside, that is to say the side of the main body of the mule directed away from the foot, can also be designed in such a way that an actuation element is no longer visible at all. This can be achieved particularly by the design as a magnet. For this purpose, for example, provision is made that a lipstick, for example, is present as a counter-magnet in an accessory of the user. This counter-magnet is simply held on the underside of the mule, that is to say on the sole in a certain area. In this way, the magnet arranged inside the main body is attracted and the existing lock between the strap and the main body is freed.
[0033] In another solution, provision is made to incorporate the actuation element into the sole of the mule. For example, the actuation element can be covered by a suitable flap. To release the straps, the flap first of all has to be opened in order to access the actuation element, in such a way that the lock between the free ends of the strap and the main body is freed.
[0034] Both of the last-mentioned embodiments have the advantage that, to an observer, it is not in any way apparent from the outside that these shoes are sandals or mules of which the straps are exchangeable.
[0035] In a further embodiment, provision is made that, in the area of the seat for the foot, the main body has a recess, an inlay stylishly matching the respective inserted strap being introduced into the recess. The inlay is fixed either by a Velcro fastener, a magnet or another type of force fit or form fit.
[0036] The inlay preferably extends from the heel area of the main body of the mule as far as the metatarsal region or even the toe region. The inlay can be made from the same material as the strap, can at least have the same color or present similar structures. In one embodiment, provision is made that the aid for actuating the fixing device for the strap is provided under the inlay. The aid can be fitted in a cavity, which is closed off from the outside by the inlay. Since the inlay is arranged releasably on the main body, the aid can also be very easily removed as and when required. It is then almost impossible for the aid to be mislaid or lost.
[0037] In order to permit simple production of such a mule according to the invention, a recess is advantageously provided in the main body on the side facing away from the foot, starting from the sole, and pointing toward the walking surface with the ground. The recess is designed in such a way that it preferably extends in the shape of a rectangle and has connection paths to the respective front faces. The front faces likewise have recesses and are designed in such a way that at least one connection exists between the front-face recesses and the recess on the sole side.
[0038] The fixing device is arranged in a housing. This affords the advantage that it can be inserted as a finished subassembly into this recess. The recess is designed in such a way that the housing fits into this recess in such a way that only minor fixing elements are still provided. If the embodiment that can be operated with a magnet is chosen, it suffices to close the recess with the sole of the mule. The fixing device is then arranged securely inside the recess. It can then still be reached only via the respective front-face recesses or the bores associated with these. In this way, very simple production is possible, without the need for elaborate working of the main body of the mule. Moreover, no mechanical working is needed that cannot be done by a shoe manufacturer, since the fixing device can already be supplied as a prefabricated subassembly.
[0039] Further advantageous embodiments will become clear from the attached drawings, the description and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] FIG. 1 shows a perspective view of the mule according to the invention, consisting of a main body and a strap connected to the main body;
[0041] FIG. 2 shows a perspective view of the mule according to FIG. 1 , but in a perspective view from underneath;
[0042] FIG. 3 shows a perspective view of a first illustrative embodiment of the device according to the invention, wherein the strap can be fixed on the main body by means of a fixing device arranged inside the main body;
[0043] FIG. 4 shows a perspective view of the mule according to FIG. 3 , but partially in a cut away view;
[0044] FIG. 5 shows a further view of the mule according to FIG. 4 ;
[0045] FIG. 6 shows a detailed view of the fixing device according to the first illustrative embodiment shown in FIGS. 3 to 5 ;
[0046] FIG. 7 shows a perspective view of a mule in a second illustrative embodiment according to the invention;
[0047] FIG. 8 shows a perspective view of the mule according to the invention, but in an exploded depiction with a corresponding fixing device;
[0048] FIG. 9 shows a view of a modified form of a fixing device shown in FIGS. 7 and 8 , namely a design as an independent subassembly;
[0049] FIG. 10 shows a perspective view of a fourth illustrative embodiment, in which the fixing device can be operated by means of a magnet;
[0050] FIG. 11 shows an exploded view of the embodiment according to FIG. 10 ;
[0051] FIG. 12 shows an enlarged view of the fixing device of the illustrative embodiment according to FIGS. 10 and 11 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0052] The basic concept of the mule 1 according to the invention is shown in FIGS. 1 and 2 .
[0053] The mule 1 according to the invention consists of a main body 2 and of a strap 3 . The main body 2 has a top 4 and an underside 5 . Side faces 6 are also provided.
[0054] The top 4 of the main body 2 serves as a seat 7 for the foot. This seat 7 is dimensioned in such a way that a foot can be arranged in its entirety on this seat. The underside 5 is divided into three areas, namely into a first area of the sole surface 8 and into a second area of the heel surface 9 . Between the sole surface 8 and the heel surface 9 , a third area 10 is provided which generally does not come into contact with the ground.
[0055] The strap 3 extends from one side face 6 of the main body to the opposite side 6 and is dimensioned in such a way that it can enclose the back of the foot (instep), such that the mule holds on the foot. The length of the strap can be adjusted by means of a width control (not shown in the drawings) which, for example, can be designed like a belt buckle. In this way, the strap 3 can be adapted to the specific circumference of the instep.
[0056] Fixing elements 12 are arranged at the free ends 11 of the strap 3 and interact with a fixing device 13 arranged inside the main body. This interaction between the respective fixing element 12 and the fixing device is described in more detail in the further illustrative embodiments and can be effected in different ways. This design difference is such that there is either a form fit or a force fit, or a combination of form fit and force fit, between the fixing element 12 and the fixing device 13 .
[0057] The fixing device 13 is arranged in or on the main body and is used to fix the strap 3 firmly on the main body 2 , but also to release the strap upon actuation of a corresponding actuation element (also not shown in the drawings) when this is desired by the user. This may be desired when the user seeks to exchange the strap 3 and, for example, replace said strap with another one.
[0058] A further purpose of the fixing device 13 and of the interaction with the fixing element 12 is that, at least while the mule 1 is being worn on the foot, it is not apparent to the consumer that the strap 3 is in any way exchangeable.
[0059] The seat 7 of the main body 2 for receiving the foot has an inlay E. This inlay E is detachably connectable to the main body 2 and preferably forms a plane with the seat 2 of the main body 2 , such that the user feels a difference at best on account of different material but not because of an edge being present. This inlay E is designed as an optical element and is provided such that, at least for optical reasons, it forms an optical unit with the strap 3 and its configuration.
[0060] This basic concept of the invention, along with the features associated therewith, is described by way of example in the illustrative embodiments below.
[0061] The above-described features can be used singly or in combination in the examples below.
[0062] However, the invention is not limited to the illustrative embodiments. Instead, all configurations are claimed that follow the basic concept, namely that of making it easy for the user to secure the strap of a mule detachably on the main body.
FIRST ILLUSTRATIVE EMBODIMENT
[0063] FIGS. 3 to 6 show a first illustrative embodiment of a mule 201 . The mule 201 comprises a main body 202 with a strap 203 detachable from the latter. The free ends 211 of the strap 203 can be arranged detachably on the side faces 206 of the main body 202 of the mule 201 .
[0064] As can be seen from FIGS. 4 and 5 in particular, the free ends have fixing elements 212 shown with a fixing device 213 , which is outlined in the figure.
[0065] The fixing device 213 is arranged inside the main body 202 and serves to arrange the strap 203 detachably on the main body 202 . An actuation element 214 , as shown in FIGS. 4 and 5 , is preferably arranged in the third area 210 on the underside 205 of the mule 201 and serves to release the fixing elements 212 from the at least force fit, such that the strap 203 is removable from the fixing device 213 .
[0066] The fixing device 213 is shown in an enlarged view in FIG. 6 . Fixing elements 212 , in which pins 212 c comprise a groove 212 b, are received with a force fit by the fixing device 213 . For the force-fit engagement, the fixing device 213 has a force-fit element 213 a with an area 213 b that engages in the groove 212 b of the fixing element 212 .
[0067] The fixing device 213 or force-fit element 213 a shown in the illustrative embodiment is movable in and counter to arrow direction 215 by actuation of the actuation element 214 . The movement is spring-loaded by means of a spring 216 , such that, when the fixing elements 212 are pressed inward in arrow direction 217 , an automatic latching of the fixing elements 212 in the fixing device 213 is obtained. The easier insertion is simplified by the pin-like formation 212 c being cone-shaped and thus being able to more easily pass through the area 213 b. For release, the actuation element 214 is actuated, and the force-fit element 213 a moves in arrow direction 215 . The fixing elements 212 snap out of the force-fit element 213 a and are released. The strap 203 can now be suitably exchanged.
[0068] To form the fixing device 213 , a cavity 218 ( FIG. 3 ) in which the fixing device 213 can be fitted is provided inside the main body 202 . This cavity 218 is preferably arranged in the area of the sole surface 208 ( FIG. 4 ) of the mule 201 . The actuation element itself can be provided both by a cover element in the area of the sole surface 208 and also, as shown in FIGS. 4 to 7 , in the third area 210 .
SECOND ILLUSTRATIVE EMBODIMENT
[0069] FIGS. 7 and 8 show a second illustrative embodiment of a mule 301 . This mule 301 consists of a main body 302 and a strap 303 to be arranged on the main body and to be detachable from the latter. The main body 302 is designed in a manner comparable to the main bodies described above. Under the sole surface 308 , it has a fixing device 313 (shown by broken lines in FIG. 8 ), which receives the fixing elements 312 (not shown in detail) with a form fit and force fit.
[0070] The fixing device 313 is arranged as a subassembly in the cavity provided in the main body 302 . By means of an actuation element, which is arranged inside the sole surface 308 and can be covered by a cover element (not shown in detail), a rotation movement 314 can be generated, as is indicated symbolically in FIG. 8 . By means of the rotation movement, the force-fit elements 313 a of the fixing device 313 are disengaged from the fixing elements 312 or from the pin-like formation thereof, such that the strap 303 can be removed from the main body 302 of the mule 301 .
THIRD ILLUSTRATIVE EMBODIMENT
[0071] FIG. 9 shows another preferred embodiment in accordance with the basic concept of the invention.
[0072] In principle, the device according to the invention is such that a mule is made available which has a strap 403 that the user is able to detach without an aid or with a small aid. At each of its free ends, the strap 403 has fixing elements 412 , which can be fitted detachably on a main body by means of a fixing device 413 . This therefore affords the user the possibility of removing the strap 403 as and when required and of exchanging it or adapting it to the clothing. The preceding examples show that a main body is made available that has a corresponding cavity into which the fixing device 413 can be installed.
[0073] It differs mainly in that the fixing device 413 according to FIG. 9 is designed as a finished subassembly for mounting on a main body 402 of a mule. This means that the fixing device 413 is arranged in a housing 430 , in such a way that the latter can be supplied as a delivery part for a shoe manufacturer. The problem arises that shoe manufacturers do not have the necessary machinery to provide such fixing devices with the corresponding fixing elements. It is therefore a considerable advantage if the fixing devices 413 can be supplied ready to function in a housing 430 , in such a way that it can be fixed in a corresponding recess in the area of the sole surface of the main body 402 of the mule 401 .
[0074] Alternatively, provision can also be made that the above-described housing 430 is a constituent part of the shoe, such that only the fixing device 413 has to be fitted. It suffices to make available a cavity having the size of the illustrated housing into which the fixing device 413 can be fitted.
[0075] The housing 430 can be arranged in its dimensions in the area of the sole surface (for example reference sign 8 in FIG. 1 or FIG. 2 ) of the mule, wherein the housing 430 already has the necessary recesses 413 a for receiving the fixing elements 412 . The fixing elements 412 can be arranged on the free ends of the straps; they are therefore only shown in this FIG. 11 in order to illustrate the function of the fixing device 413 .
[0076] Moreover, the actual force-fit element 413 b is arranged rotatably on a bearing device 413 c in the housing 430 . Spring elements (not shown in detail) press the force-fit element 413 b into the position in which a locking with the fixing elements 412 is to be effected when these are each fully inserted into the recesses 413 a.
[0077] The force-fit element 413 b is preferably of symmetrical construction and is mounted centrally. At its free ends, it has means 413 d that interact with the fixing elements 412 . The interaction is such that the means 413 d have u-shaped formations which, by pivoting of the force-fit element 413 d, engage in the grooves 412 b provided by the fixing elements 412 . A force fit is achieved by the engagement of these u-shaped formations. Since the free ends of the fixing elements 412 have pin-like formations 412 a, which engage in bores 413 e, a correct positioning of the fixing elements 412 is achieved, such that a reliable locking of force-fit element 413 b with the fixing element 412 is achieved. The free ends of the pin-like formations 412 a are preferably cone-shaped, such that, when the fixing elements 412 are pressed into the recesses 413 a of the housing 430 , the bores 413 e are penetrated, and then the cone-like free ends effect a slight rotation of the force-fit element 413 b until it automatically snaps back, such that the locking is brought about.
[0078] In order to exert the corresponding rotation in or counter to arrow direction 416 , an aid 415 is provided that engages in an actuation element 414 . The actuation element 414 is rotatably connected at least indirectly to the force-fit element 413 a via a slide element 417 .
[0079] With the aid 415 , the user can disengage the force-fit element 413 a from the fixing elements 412 by rotation in or counter to arrow direction 416 . Since provision is made for automatic locking to take place when the fixing elements 412 are pressed into the force-fit element 413 b, active rotation via the actuation element 414 is only necessary when the user wishes to release the fixing elements and exchange the strap.
[0080] The subassembly can be joined together with a small number of fastening elements. Clip connections or screw connections are preferably used in order to ensure simple and inexpensive production of this subassembly.
[0081] Instead of the housing 430 in FIG. 9 , the subassembly, when joined together as shown here, can also be fitted into a cavity provided in a main body of a mule. The subassembly is in this case reduced to the fixing element.
FOURTH ILLUSTRATIVE EMBODIMENT
[0082] FIGS. 10 to 12 show a fourth preferred illustrative embodiment in accordance with the basic principle of the invention. In principle, the device according to the invention is such that a mule is made available with a strap 503 in that way that the user is able to detach it with small auxiliary means. At its free ends, the strap 503 has fixing elements 512 , which can be fitted detachably on a main body 502 by means of a fixing device 513 . This therefore affords the user the possibility of removing the strap 503 as and when required and of exchanging it or adapting it to the clothing. The preceding examples show that a main body is made available that has a corresponding cavity into which the fixing device 413 can likewise be installed.
[0083] The fixing device 513 differs from those according to the first and second illustrative embodiments in that, as in the third illustrative embodiment, it is designed as a finished subassembly for mounting on a main body 502 of a mule. This means that the fixing device 513 is preferably arranged in a housing 530 , in such a way that the latter can be supplied as a delivery part for a shoe manufacturer. The problem arises that shoe manufacturers do not have the necessary machinery to provide such fixing devices with the corresponding fixing elements. It is therefore a considerable advantage if, as in the third illustrative embodiment too, the fixing device 513 can be supplied ready to function in a housing 530 , in such a way that it can be fixed in a corresponding recessed area of the sole surface of the main body 502 of the mule 501 .
[0084] The housing 530 can be arranged in its dimensions in the area of the sole surface of the mule, wherein the housing 530 is designed with a box shape. A force-fit element 513 b is arranged inside the box shape, as is shown in FIG. 12 for example, and engages like a bracket in the grooves 512 b provided by the fixing elements 512 . The grooves 512 b are again arranged on pin-like formations 512 a of the fixing element 512 . The fixing elements 512 are adjoined, as is indicated in FIG. 10 , by the strap 503 .
[0085] The force-fit element 513 b is of symmetrical construction and is mounted movably on bearing elements 513 f in and counter to arrow direction 513 g. Spring elements 513 h serve to effect the spring-loaded movement according to arrow direction 513 g.
[0086] A plate element 513 i limits the height movement in arrow direction 513 g ( FIG. 12 ).
[0087] To provide a locking action, the fixing elements 512 are inserted into the recesses 513 a of the main body 502 of the mule 501 . By means of the insertion, a corresponding form fit is obtained firstly with the outer contour of the fixing element 512 . The pin-like formation 512 a moves through a bore provided in the main body in the recess 513 , and then through an opening 513 e, which is arranged on the main body 530 . On account of the bracket-like design of the force-fit elements 513 d, the locking action is brought about when force is exerted on the fixing elements in arrow direction 512 c, in such a way that the free ends of the force-fit element 513 b engage in the groove 512 b of the fixing element 512 . The locking action is thus brought about.
[0088] To cancel the locking action, a magnetic element 515 is now held, as shown in FIG. 10 , on the sole surface, that is to say on the underside of the mule. In this way, a magnet 516 , which interacts with the housing cover 513 i of the subassembly, is moved in arrow direction 517 ( FIG. 11 ). Since the plate element 513 i is spring-loaded, it likewise moves in the arrow direction, in such a way that the force-fit element 513 b likewise moves in this arrow direction. In this way, the free ends 513 b of the force-fit element disengage from the grooves 512 b of the fixing elements 512 and thus release the force-fit connection. Depending on the choice of material of the strap, the form-fit connection between the fixing element 512 and the recess 513 a is maintained or, because of the corresponding pretensioning, it is also accordingly canceled.
[0089] When the magnetic element 515 is spatially removed from the sole, the plate element 513 i recovers its original position. This is again achieved by the spring action. The force-fit elements 513 d thus return to their original rest position, such that they are ready to receive the fixing elements 512 .
[0090] Alternatively, provision is also made that the magnetic element 516 interacts with a further component part 518 , which is in form-fit and force-fit connection with the force-fit element 513 b. If the magnet 515 is held on the outside of the sole as has already been described above and as is shown in FIG. 10 , it is thus possible that the magnet 516 is moved together with the component part 518 in arrow direction 517 , specifically counter to the spring force provided by the springs 513 h. As has likewise been described above, the fixing element is thus also disengaged from the fixing device.
[0091] Instead of the housing 530 described in FIG. 11 , the subassembly, when joined together as shown here, can also be fitted into a cavity provided in a main body of a mule. The subassembly is in this case reduced to the fixing element. A housing is then not necessary.
[0092] The basic concept of the invention is thus to make available a mule that has exchangeable straps. These straps can be secured on the main body in different ways. They can be secured using force-fit and also form-fit connections and also combinations thereof. The basic concept is also such that, when the shaped elements arranged at the free ends are simply pressed in, an at least form-fit but also preferably force-fit connection is established between the strap and the main body. Provision is made for an actuation element to be activated only in order to detach the strap from the main body. The activation can be effected either using a coin, by inserting the latter into a slot (comparable with a screwdriver or an auxiliary element such as a key). The generally tensioned shaped elements are then released by a simple rotation. They are tensioned because the material from which the strap is made does not assume the shape and it is therefore sought to resume an elongate shape as soon as a force fit is canceled.
[0093] As an alternative to the above-described actuation element, provision can also be made that the fixing device, or the locking of fixing element and fixing device, is released without a force-fit and form-fit connection. By means of a magnet, the locking action can be canceled without any outward sign that any such thing is present. This has an extremely high esthetic value and, moreover, this device can be operated very easily by anyone.
[0094] An accessory, for example lipstick, a comb, a mirror or the like, can be installed in the magnetic element that can serve to cancel the locking action. It is then only necessary for the user to hold this accessory on the sole area until a suitable sound clearly indicates that the locking action is now canceled. Depending on the pretensioning of the straps, this can already be observed visually, or a small slight movement has to be performed in order to likewise cancel the form fit that is still present between the fixing elements and the recess.
[0095] In one particular embodiment, the fixing device is designed as a subassembly that can be arranged as a finished unit on a main body of a mule, in order to easily implement the basic concept of the invention.
[0096] For this purpose, a cutout is provided inside the mule on the underside, wherein recesses are to be made on the sides that are designed for the fixing elements.
[0097] The subassembly is also very easily fitted into the cutout itself. The corresponding cutout can then be covered exclusively by the fitted sole, without additional effort to further design the fixing device. The fitting is thus very simple and can be carried out by anyone without further tools. | The invention relates to a mule ( 1, 201, 301, 401, 501 ) with at least one strap ( 3, 203, 303, 403, 503 ) detachably arranged on the mule. According to the invention, the strap ( 3, 203, 303, 403, 503 ) can be arranged on the main body optionally either by a form fit and/or force fit or by a force fit or by a form fit and is detachably connected. A fixation device ( 13, 213, 313, 413, 513 ) that cooperates at least indirectly with the free ends of the strap ( 3, 203, 303, 403, 503 ) is provided inside the main body ( 2, 2, 302, 402, 502 ) and means are provided that bring about a simultaneous detachment of the free ends of the strap ( 3, 203, 303, 403, 503 ). | 0 |
FIELD OF THE INVENTION
[0001] This invention relates to pipe couplings where the pipe is made from plastic such as polyolefin, polyvinyl chloride or ductile iron or similar materials that are at least slightly deformable under localized pressure. In particular, this invention relates to an improved gripper ring for use in couplings where a sealing ring is compressed by a portion of a ring member when the coupling is installed. Specifically, the gripper ring is provided with a plurality of annular teeth which extend radially inwardly to different distances relative to the axis of the coupling and pipe end being coupled.
BACKGROUND OF THE INVENTION
[0002] In many fluid handling systems, couplings for pipe ends are employed in constructing the system and the prior art has proposed a variety of different coupling structures to enable users to install the systems with secure couplings or joints between pipe ends. In some of these designs, a portion of the flow path is obstructed by the coupling mechanism and this is undesirable as the obstruction causes premature wear on the pipe particularly where the fluid being carried includes solid materials. In other arrangements, the labor required to establish the coupling is excessive due to the number of parts that must be used to assure a leak proof connection. In still other systems, where the couplings are located, for example, under vehicle thoroughfares, the stability of the coupling is adversely affected by heavy traffic leading eventually to leakage or failure of the coupling.
[0003] In view of these difficulties, there is a need for a secure, leak free pipe coupling that can be easily and quickly installed, has few parts and provides a clear flow path through the coupling.
SUMMARY OF THE INVENTION
[0004] The coupling of the present invention, in one form, includes a sleeve having enlarged ends for receiving a pipe end. The sleeve includes two or more apertured flanges at each end for receiving a tightening bolt. The interior of the sleeve may include a seat for the end of the pipe and a wall portion that is slanted relative to the axis of the sleeve to serve as a seat for a seal member. The sealing elements of the coupling include a slide ring, a gripper ring and a locking ring. The locking ring includes apertures for receiving the tightening bolts and has a radially inner surface that is slanted axially and engages an outer slanted surface of the gripper ring. The slide ring and gripper ring each have mutually abutting ends with the opposite end of the slide ring engaging a flexible seal ring or annular gasket to compress the gasket into sealing engagement with adjacent surfaces of the coupling. The gripper ring has a plurality of radially inwardly extending annular edges or teeth members, the radial extent of which differ from adjacent edges or teeth members to improve the gripping action of the gripper ring when the tightening bolts are tightened to urge the gripper ring axially toward the slide ring and seal member.
[0005] With this structure, the action of the teeth will penetrate the surface of the pipe being coupled when moved by the tightening bolts to effectively lock the position of the slide ring against the seal member.
[0006] The foregoing and other advantages of the invention will become apparent as consideration is given to the following description and the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] [0007]FIG. 1 is section view of one end of a pipe coupling according to the present invention;
[0008] [0008]FIG. 2 is a detailed view in section of a portion of the gripper ring;
[0009] [0009]FIG. 3 is a detailed view in section of the gripper ring engaging the surface of a pipe end; and
[0010] [0010]FIG. 4 is a detailed view in section similar to FIG. 3 but showing a variation of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0011] Referring to the drawings, wherein like numerals designate corresponding parts throughout the several views, in FIG. 1 there is shown a sectional view of a coupling 10 for two pipe ends one of which is shown at 12 inserted into a coupling sleeve 14 . It will be understood that this view is symmetrical about the center of sleeve 14 and only the left end elements of the coupling 10 are illustrated, the opposite end being identical.
[0012] The coupling sleeve 14 is provided with an enlarged end 16 which includes a slanted interior wall 18 and the pipe end seat 20 . Externally of the end 16 are provided two or more flanges 32 which are apertured to receive tightening bolts as described below. The coupling 10 further includes a tightening ring 22 which surrounds a gripper ring 26 , one end of which abuts a slide ring 36 which, in turn, abuts for compression purposes a resilient seal ring 38 , one side of which abuts the slanting wall 18 of the sleeve end 16 .
[0013] The tightening ring 22 has two or more bores 28 for receiving tightening bolts 30 so that the bolts will each extend through a bore 28 and through the aperture in the flange 32 . Preferably, the bolts have an anchoring portion or catch 34 to facilitate engagement between the tightening ring 22 and the flanges 32 of the sleeve 14 . With this arrangement, tightening of the nuts 52 on the threaded ends of the bolts 30 secure the elements together and assure a fluid tight seal as described below.
[0014] The radially interior surface 24 of the tightening ring 22 is slanted to cooperate with a complementary surface 48 on the gripper ring 26 . The end of the gripper ring 26 opposite the slanted surface 48 is preferably flat or planar, as shown in FIGS. 2 - 4 , to provide a stable engagement with the planar surface 49 of the slide ring 36 . To improve the compression of the seal ring 38 , the opposite side 51 of the slide ring 38 is slanted substantially to the same degree as the opposite wall 18 of the sleeve 14 . The surface 51 and the wall 18 together define a cavity for the seal ring 38 with the wall 18 being movable toward the slide ring 36 when the nuts 52 are tightened on the end of bolts 30 . Thus, once the resilient seal ring 38 is compressed between surface 51 and 18 , the radial expansion of the seal ring 38 due to the orientation of the surfaces 51 and 18 will assure leak proof operation of the seal ring 38 .
[0015] According to the present invention, the chance that the compressive force of the coupling on the seal ring 38 will be decreased is minimized by the construction of the gripper ring 26 . Such a diminution of the force compressing the seal ring 38 may be due to vibrations imposed on the coupling where the pipe is buried under a roadway which is subjected to heavy traffic. Over time, such continued vibrations can result in wear on the connecting flanges 32 and the catch 34 or even in loosening of the threads of the nuts 52 . Of course, other environmental conditions may also result in a tendency for the compressive force imposed by the tightened bolts 30 to decrease such as extreme temperature changes either externally or due to the temperature changes of the material being carried through the pipe 12 . To counteract these effects, the present invention provides a unique set of annular gripping edges or teeth 40 , 42 , 44 and 46 on the radially inner surface 41 of the gripper ring 26 . A shown in FIG. 2, each tooth is provided with a radially extending surface 44 a and a slanted backup surface 44 b which extends at an angle from the inner edge 47 . Of primary importance is the different heights to which the teeth extend with the teeth adjacent the axially outer end of the gripper ring 26 as at 40 and 42 extending radially inwardly from the surface 41 of the body of the ring 26 . As shown in FIGS. 2 - 4 , the inner teeth 44 and 46 differ in height slightly from the axially outer teeth 40 and 42 . Preferably, this difference in the radial extents will be on the order of 0.0200 in. However, this will have a major impact on the gripping force exerted by the ring 26 once it engages the surface of the pipe 12 being coupled as will be evident from FIGS. 3 and 4 to which reference is now made below.
[0016] With the coupling established as shown in FIG. 1, an operator will commence tightening and securing the coupling by tightening the nuts 52 on the bolts 30 . Initially, this will result in sliding movement of the gripper ring 26 and the slide ring 36 over the surface of the pipe 12 to result in a compression of the O-ring 38 . Continued tightening of the nuts 52 will, however, cause the force exerted by the surface 24 of the tightening ring 22 to be transmitted to the surface 48 of the gripper ring 26 and where the pipe is polyethylene or polyvinyl chloride material, the central teeth 44 and 46 will commence penetration of the surface of the pipe 58 as shown in FIG. 3. Continued tightening of the nuts 52 will cause the outer teeth sets 40 and 42 to also penetrate the surface of the pipe 58 . Where the gripper ring 26 is made of the coated steel or ductile iron, and the pipe 58 is of a plastic material as described above, penetration on the order of about 0.04 inches for the central teeth 44 and 46 will be effected while the penetration of about 0.02 inches for the outer teeth 40 and 42 of the gripper ring will be effected.
[0017] Where the pipe 60 is a metal such as ductile iron, the penetration of the teeth 44 and 46 of the gripper ring will be substantially shallower then is the case with a plastic pipe 58 . Typically, a penetration for the larger teeth 44 and 46 will be on the order of about 0.01 to 0.02 in. In most cases, the shorter teeth 40 and 42 will not penetrate the surface of the iron pipe 60 . This should be acceptable in almost all applications as the ductile iron pipe will not exhibit the effects of the traffic induced vibrations to the same extent as the plastic pipe 58 .
[0018] There are several advantages to use of a gripper ring 26 having at least two sets of teeth of different radial heights. Firstly, one type of the gripper ring need be manufactured to achieve secure gripping in either a plastic or a ductile iron pipe. Secondly, once the teeth of the gripper ring 26 are embedded in the surface of the pipe, substantially uniform compression of the resilient O-ring seal 38 will be assured over a wide range of conditions.
[0019] Having described the invention, it will be apparent to those skilled in this art that various modifications can be made to the invention with departing from the spirit and scope of the invention. | A pipe coupling has an enlarged end for receiving a pipe end and a flange apertured for supporting coupling bolts; a tightening ring is placed around the pipe end and includes a slanted radially inner surface cooperating with a gripping ring; a slide ring is placed about the pipe end to be engaged by an end of the gripper ring; the enlarged end has a seal cavity with an inner slanted surface for engaging a seal ring; the gripper ring has two pairs of teeth extending radially inwardly to different extents with the axially inner pair being of greater length than the outer pair. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to methods for certifying or validating the existence or occurrence of a recorded document or event, particularly methods which rely upon cryptographic assumptions to establish the basis for such a certification or validation. More specifically, the invention relates to a method for reconfirming an original certificate in order to maintain its validity for a significant period of time beyond the probable compromise of an underlying cryptographic assumption or step in the original certification procedure.
Time-stamping procedures described in U.S. Pat. Nos. 5,136,646 and 5,136,647 are representative of a type of certification for which the present method is adapted. Such schemes for setting a reliable time of creation of a document, or providing indisputable evidence against the alteration of a document, generally digital computer data in alphanumeric, pictorial, video, or audio form, depend upon the assumption that there exist cryptographic functions which, when applied to a digital representation of such a document, defy any manner of manipulation which might permit undetectable alterations or falsifications of the original state of document elements. The functional procedures generally exemplified in those disclosures typically provide this required property, since they generate unique certificate statements which essentially can not be duplicated other than from an identical document representation. This security arises from the fact that the derivation or reconstruction of these functions from the products of their application is computationally infeasible. Ultimate achievement of such derivations must be anticipated, however, since a given function or procedure may be fatally flawed or, as is becoming more probable, advancements in computer technology and algorithmic techniques are likely to make more readily available a level of calculating power which enables such derivation.
With compromise of a step or algorithm in a procedural certification function, the possibility arises of generating duplicate certificates or parts thereof from different digital representations, i.e., creating "collisions", and thereby defeating the previously reliable basis for a certification scheme. Substitution of a newer and presumably less vulnerable function in the certification procedure may prevent for some finite time the compromise of future certificates, but the value of past certificates in establishing original creation dates, for example, is all but lost. The present invention, however, provides a means for bridging the technological gap and extending into the era of a newer function or procedure the validity of the original certification.
SUMMARY OF THE INVENTION
Historically, there has usually been an overlap period between the time spans of reliability of an established cryptographic function and one which has been newly implemented with improved resistance to compromise. As computational power increases and algorithmic techniques improve, the evolution and phasing of cryptographic certification procedures or functions, for example, can generally be foreseen, It is possible, therefore, to anticipate the final stages of reliability provided by an existing certification scheme and to initiate a procedure, such as provided by the present invention, to ensure the continuity of original certificate validity.
In essence, this invention entails generating from the original document a new document certificate during the viable term of the original certification scheme, such as may be based upon a cryptographic signature key procedure or a time-stamping procedure. This new certification process comprises applying a different cryptographic function, e.g., a time-stamping procedure, to a combination including the original certificate and the original digital document from which the certificate was derived. Such a different function is preferably a new and presumably more reliable algorithm or procedure, or at least one upon which the original certification did not rely. The resulting certificate, generated by means of a function or procedure having a significant expected remaining term of reliability, now implacably embodies the original certificate elements at a time prior to any likely compromise of the original certification function. Since these original elements have as yet been exposed to no threat of compromise and are now bound by the new time stamp within the protective cloak of a far more relatively invulnerable certification function, their original veracity has been extended for at least the reliable term of this new function.
BRIEF DESCRIPTION OF THE DRAWING
The present invention will be described with reference to the accompanying drawing of which:
FIG. 1 presents a flow chart of steps embodying a general procedure implementing the certificate extension process of the invention; and
FIG. 2 presents a flow chart of steps embodying a rudimentary time-stamping procedure implementing the certificate extension process of the invention.
DESCRIPTION OF THE INVENTION
The extension procedure of the present invention is applicable to any manner of certificate digitally derived by cryptographic means, For instance, the process may be used to support the veracity of a document transmittal originally certified with a cryptographic key signature algorithm or function beyond a time when that function might be compromised, whether due to misappropriation of a secret key or to advances in computer technology and algorithmic techniques. A digital time-stamp certificate could similarly benefit by application of the invention to prevent its coming into question after compromise of the scheme or function underlying the time-stamping procedure. In general, the process of the invention is useful to ensure the continued viability of any certificate produced by a digital scheme or function which is capable of compromise.
The steps comprising a basic application of the certificate extension process are shown in FIG. 1. There, initial steps 11, 13 are intended to depict any certification procedure, such as a signature scheme or time-stamping process, in which a digital document, D 1 , e.g., a body of text or alphanumeric representations, a picture, an audio recording, or the like, is subjected to a cryptographic scheme or procedure, generally a "function", F 1 , to produce a certificate, C 1 , which will serve later as evidence of the original existence and substance of D 1 . The value of certificate, C 1 , will persist, however, only until a compromise of the certification function, as a whole or in a component step or algorithm, since, as a result of such a compromise, the certificate might thereafter be duplicated by an imposter or through the use of a counterfeit document.
The basic steps of the invention are therefore effected prior to any such compromise, as projected, for example, on the basis of the current state of computational technology, and comprise combining, at 15, the original document, D, with the original certificate, C 1 , and applying to that combination, at 17, a different and presumably more secure scheme or function to obtain a new certificate, C 2 , which will later attest to the validity of original certificate, C 1 , at a time when its generating function, F 1 , was as yet uncompromised and secure. The essential element of this process resides in the application of the new certification function to the conjunction of original document, D, with original certificate, C 1 . This step avoids the error inherent in the naive and ineffectual procedure of merely recertifying either the original certificate or the original document alone; namely, that of perpetuating a compromise which reflects directly upon the veracity of the original document, D.
As an example, one might consider application of the present invention to extend the valid lifetime of a digitally signed document where, in keeping with usual practices, a digital signature, σ, is derived by application of some cryptographic signature scheme to a document, D. To avoid invalidation of such a signed document by subsequent compromise of the scheme, for instance, due to misappropriation of a user's private key, the pre-compromise generation of a certificate, C, by application of a time-stamp function, T, to a combination of the signature and the document:
C=T(σ,D)
will provide continuing proof that the signature was created prior to the compromise, i.e., at a time when only a legitimate user could have produced it. Such a certificate might also be used to establish original authorship of the document.
The invention is broadly useful, as well, as a means of extending or "renewing" time-stamp certificates, generally. For example, a simple scheme for certifying an event, such as time-stamping the creation of a document, comprises establishing a digital representation of the document content, adding data denoting current time, and permanently fixing the resulting digital statement against subsequent revision, all under trustworthy circumstances, to yield a certificate which will provide irrefutable evidence of the event at a later time. Means for ensuring the original veracity of the certificate have been described in our earlier-noted patent specifications as including use of trusted outside agencies, arbitrary selection of agencies, linking of certificates in temporal chains, and similar practices which remove substantially all influence a document author might have upon the certification process. Other methods of establishing the authenticity of original certification procedures might also include private and public key cryptographic communications.
Common to certification procedures is the application of some manner of cryptographic function by which the document, related identifying data, or digital representations of these elements may be algorithmically reduced to a unique statement or cipher which can not feasibly be duplicated from different representative elements by computational means. Any of the general class of one-way hashing algorithms, for example, may be used in such a procedure or function applied to a digital representation of a time-receipted document to produce an inimitable certificate, usually in the form of a cryptic string of alphanumeric characters, which can only be generated by such an application of that same function to exactly that digital representation. The additional characteristic property of the one-way function is that of possessing such mathematical complexity as to discourage the computational derivation or reconstruction of the original digital representation from the resultant certificate, as well as to discourage the generation of a matching certificate from a different representation.
A simple certification procedure utilizing such a one-way hashing algorithm is represented in FIG. 2 at steps 21-23. There, digital document, D 1 , of step 21 is identified , e.g., annotated with author data, to yield a receipt, R 1 , that, in a rudimentary procedure which may be simply stated as:
C.sub.1 =F.sub.1 (H.sub.1 (R.sub.1))
is in turn reduced at step 23 to a certificate, C 1 , by application of a time-stamping function, F 1 , comprising a current hash algorithm, H 1 .
As a result of computational or algorithmic developments over time, or in the event of a flaw in the function itself, hash, H 1 , may become compromised with the result that a falsified receipt, R x , could produce a duplicate, or "collision", certificate, C 1 . The veracity of original certificate, C 1 , and its value as probative evidence of the contents of document, D, and other elements of receipt, R 1 , would thus be destroyed, since there would no longer exist a singular certificate cipher that could be traced solely to the original document and its once-unique receipt, R 1 .
Advent of the collision need not denigrate the worth of the initial certificate back to the time of its creation, however, but only for the period subsequent to the compromise. The value of the certificate during its earlier term could be preserved and extended into the future if means were available to link into a time prior to such compromise with a trustworthy scheme for deriving a new certificate at least as unique and intractable as was the initial certificate. The problem, therefore, has been to "recertify" the original certificate in a manner which would verify the facts that had been securely bound into that certificate until the first collision occurred.
A naive solution to this problem would appear to be just that simple; that is, to recertify the original certificate, for example by applying a new and more robust hash, H 2 . The fallacy in this approach becomes apparent, however, when one considers that after the instance of a collision the condition exists where:
H.sub.1 (R.sub.1)=C.sub.1 =H.sub.1 (R.sub.x).
The hashing of certificate, C 1 , with a new function, H 2 , would therefore not produce a renewal certificate cipher, C 2 , unique only to receipt, R 1 , since:
C.sub.2 =H.sub.2 (C.sub.1)=H.sub.2 (H.sub.1 (R.sub.1))=H.sub.2 (H.sub.1 (R.sub.x))
and, thus, there is no reliable distinction between those resulting certificates.
The present invention, however, does provide such a unique certificate which serves to extend the veracity of an original certificate beyond subsequent compromise of the original function or algorithm. This is accomplished, as in the representative of FIG. 2, by combining, at step 25, the original certificate, C 1 , with the original document, D 1 , from which it was generated and which is to be later proven, and applying to that composite statement, at step 27, a different certification function, F 2 , e.g., comprising a new hashing algorithm, H 2 , to yield the extended certificate:
C.sub.2 =F.sub.2 (H.sub.2 (C.sub.1,D.sub.1))=F.sub.2 (H.sub.2 (H.sub.1 (R.sub.1),D.sub.1)).
The final represented step, 29, in which it is established that the new certificate, C 2 , was created during the valid term of original certificate, C 1 , i.e., prior to any compromise of the original certification function, may be effected along with step 27, for example in the course of applying an earlier-described time-stamping procedures, to generate certificate, C 2 . Alternatively, the effective time of the new certificate, C 2 , may be established simply by publication, e.g., in a widely-distributed newspaper, either alone or as incorporated into a derivative representation similar to the "authentication tree" noted by D. E. R. Denning in Cryptography and Data Security, pp. 170-171, Addison-Wesley (1982).
In the ultimate utilization of this new certificate, C 2 , to prove the original document, D 1 , by recomputing certificate, C 2 , from its elements, such proof will fail unless original document, D 1 , rather than a bogus document, D x , is an included element. Even though a collision due to compromised function, H 1 , may exist at the time of using certificate, C 2 , in a proof, the as yet invulnerable state of hash function, H 2 , ensures against any collision with the expanded statement, i.e., one comprising document element, D 1 , which is used to generate that new certificate. During a normal proofing process, the original certificate, C 1 , will also be recomputed using the document in question. Unless the document then employed to recompute original certificate, C 1 , matches precisely the document similarly employed with new certificate, C 2 , the proof will not be realized. A false document, D x , therefore can not be substituted surreptitiously for an original document as long as the applied hash function, H 2 , remains uncompromised, since for any document, D x , which one could feasibly compute:
H.sub.2 (C.sub.1,D.sub.1)≠H.sub.2 (C.sub.1,D.sub.x).
When advancements in computation portend a compromise situation, yet a different time-stamp function, e.g., one utilizing algorithm, H 3 , with longer life expectancy may be employed in the same procedure to again extend the involved certificate.
As an example of the implementation of the present invention, one might consider first an initial certificate prepared in the manner described in our earlier U.S. Pat. No. 5,136,646 employing the one-way hash algorithm specified by R. L. Rivest in "The MD4 Message Digest Algorithm", Advances in Cryptology--Crypro '90, Lecture Notes in Computer Science, Vol. 537 (ed. A. J. Menezes et al.), pp. 303-311, Springer-Verlag (Berlin, 1991). In that earlier example, elements of the receipt, R 1 , identifying the quotation "document" appeared as:
1328, 194628GMT06MAR91, 634,
ee2ef3ea60ef10cb621c4fb3f8dc34c7
and with additional data representing a prior transaction formed the basic statement to which the function comprising MD4 hash algorithm, H 1 , was applied to yield the unique cipher:
46f7d75f0fbea95e96fc38472aa28ca1
which is held by the author as a time-stamp certificate, C 1 .
In the event of an anticipated compromise of the MD4 hash function algorithm, the procedure of this invention would be initiated utilizing a different time-stamping certification function comprising, for example, a new algorithm, H 2 , such as the MD5 hashing function described by Rivest and Dusse, "The MD5 Message Digest Algorithm", Network Working Group, Internet Draft, RSA Data Security, Inc. (July 1991); RFC 1321, Internet Activities Board (April 1992).
As an initial step in this procedure, the document representation, D 1 , to be proven at a later time is combined with original certificate, C 1 , either in original digital form or, preferably, as the convenient, condensed output of hash function, H 2 , viz.:
.D9776652kDAj2.M5191CAD7
thus forming the combination statement, (C 1 , D 1 ), as:
46f7d75f0fbea95e96fc38472aa28ca1,
.D9776652kDAj2.M5191CAD7.
Applying to this statement hashing algorithm, H 2 , comprising the new function, F 2 , produces:
656h//PDDM60M9/qDDt85F56
which in a time-stamping procedure, for instance, may be transmitted to an outside agency for the inclusion of current time data and authenticating cryptographic signature to yield extended certificate, C 2 . As earlier noted, the effective date of a new certificate, C 2 , may otherwise be established, such as in other time-stamping schemes or by public display or notoriety.
A variation on the foregoing embodiment provides an even more reliable practice in that it substantially eliminates the uncertainties associated with estimating the onset of a certification function compromise. This is accomplished by using a plurality of different cryptographic functions, e.g., F a and F b , to derive a compound original certificate, C.sub.α :
C.sub.α =F.sub.a (D.sub.1),F.sub.b (D.sub.1).
which will remain valid even after the confirmed compromise of one of those function due to the likely continued viability of the other. Thus a period of security continues during which one may select a new certification function, F c , to be employed in the extension of certificate, C.sub.α as:
C.sub.β =F.sub.b (C.sub.α, D.sub.1), F.sub.c (C.sub.α, D.sub.1).
Subsequent compromise of any current cryptographic function can be remedied in like manner.
It is anticipated that other variants will become apparent to the skilled artisan in the light of the foregoing disclosure, and such embodiments are likewise considered to be encompassed within the scope of the invention defined by the appended claims. | A cryptographic certificate attesting to the authenticity of original document elements, such as time of creation, content, or source, will lose its value when the cryptographic function underlying the certifying scheme is compromised. The present invention provides a means for extending the reliability of such a certificate by subjecting, prior to any such compromise, a combination of the original certificate and the document digital representation from which that certificate was derived to a scheme based on a different and ostensibly less vulnerable function. The new certificate resulting from this procedure extends the validity of the original authenticity by implacably incorporating the original certificate at a time when that certificate could only have been derived by legitimate means. | 7 |
BACKGROUND
[0001] The present invention relates to information management.
[0002] Currently, most information that is presented to the users of an information system is assembled from smaller pieces of information or content. These smaller pieces of information tend to evolve as the information is updated or otherwise modified to reflect changes that tend to occur over a period of time. Further, these smaller pieces of information are frequently available, or must be made available, in a number of different versions (e.g., to represent the information in different languages).
[0003] Typically, in order to keep track of such changes, specific references, such as hyperlinks between hypertext markup language (HTML) pages, are used to link the smaller pieces of information. By linking the smaller pieces of information, larger sets of information can be presented to the user. Although this enables the smaller pieces of information to be linked into meaningful content, this system can be cumbersome when the smaller pieces of information must be updated. In addition, presentations of information in alternate languages are frequently performed by merely applying a word-by-word translation from the source language into a target language. Such a translation is less than ideal, as a single term can often have different translations, depending on the context in which the term is used.
SUMMARY OF THE INVENTION
[0004] The present invention provides methods and apparatus, including computer program products, implementing techniques for the identification of data elements and the context in which the data element is being used.
[0005] In one aspect, the techniques include receiving a first user input comprising a data element in a data set and a context in which the data element is being used, and sending the first user input to a terminology database. The techniques also include receiving a list of entries from the terminology database based on the first user input, each entry having a corresponding first unique identifier (UID) and a second, distinct UID, wherein the first UID represents a concept associated with the data element, and the second UID represents a specific description of the concept associated with the data element. The techniques further include receiving a second user input selecting a selected entry from the list of entries, and directly associating the first UID and the second UID corresponding to the selected entry with the data set.
[0006] Implementations of the invention can include one or more of the following features. Directly associating the first UID and the second UID with the data set may comprise generating markup code comprising the first UID and the second UID. The markup code may be in an extensible markup language (XML) format. The markup code may include attributes attached to the data element that specify the first UID and the second UID. The first UID and the second UID may be linked to the terminology database.
[0007] In another aspect, the techniques include receiving a data set comprising of a data element, a first UID associated with the data element, and a second, distinct UID associated with the data element, wherein the first UID represents a concept associated with the data element, and the second UID represents a first description of the concept associated with the data element; and using the first UID to search for information related to the concept associated with the data element.
[0008] Implementations of the invention can include one or more of the following features. Information related to the concept may comprise a second, distinct description of the concept. The first description may be in a first language and the second, distinct description may be in a second, distinct language. The information related to the concept may comprise a second data element. The techniques may further comprise receiving a link, wherein the link points to a specific target data element and the link contains both the first UID and the second UID of the target data element, and verifying the link by matching the second UID contained in the link to the second UID associated with the specific target data element. The second UID may identify a specific revision of the data element.
[0009] In another aspect, the techniques include receiving a user input comprising a data element in a data set. The techniques further include receiving a first UID and a second, distinct UID, wherein the first UID represents a concept associated with the data element, and the second UID represents a specific description of the concept associated with the data element. The techniques also include directly associating the first UID and the second UID with the data set, wherein directly associating the first UID and the second UID with the data set comprises generating markup code comprising the first UID and the second UID. The techniques may further include using the first UID to search for information related to the concept associated with the data element.
[0010] The techniques can be implemented to realize one or more of the following advantages. Small pieces of information content can be cataloged consistently. The small pieces of information can be identified without requiring constant access to databases that manage these small pieces of information. The small pieces of information can be reused between different pieces of information content. The techniques provide support for localization, maintenance, and quality assurance tasks.
[0011] The techniques can be used to translate terms in documents in a manner that captures the nuances of certain words or phrases. The techniques provides the ability to implement a more efficient solution for the features and requirements related to versioning, updating, and translation in the realm of hypertexts.
[0012] One implementation of the invention provides all of the above advantages.
[0013] These general and specific aspects can be implemented using a computer program, a method, a system or apparatus, or any combination of computer programs, methods, or systems. Details of one or more embodiments of the invention are set forth in the accompanying drawings and in the description below. Other features, objects, and advantages of the invention will be apparent from the description, the drawings, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 illustrates a concept-based content architecture system.
[0015] FIG. 2 is a flow chart illustrating the assignment and association of Globally Unique Identifiers (GUIDs) to data sets.
[0016] Like reference numbers and designations in the various drawings indicate like elements.
DETAILED DESCRIPTION
[0017] FIG. 1 shows a concept-based content architecture system 100 that associates unique identifiers with data elements in data sets. The content architecture system contains a frontend system 125 , a backend system 130 , and a terminology repository or database 135 .
[0018] In one implementation, the frontend system 125 can be the Knowledge Workbench from SAP AG of Walldorf (Baden), Germany (SAP). The backend system 130 can be the Knowledge Warehouse, also from SAP, and the terminology database 135 can be SAPTerm. The Knowledge Warehouse is a tool that supports various activities related to the creation of software manuals.
[0019] A user can access the system 100 by using the frontend system 125 . Through the frontend system 125 , the user has access to a number of data sets that are contained within the system. A data set is a collection of units of content. Data sets can include text documents, data files, database entries, or any other type of resources that can be stored and accessed through the backend system 130 . In one implementation, the data set is an extensible markup language (XML) document. Typically, each of these data sets is comprised of data elements, where each data element represents a unit of content. As each data set can be comprised of multiple data elements, the user can easily create new data sets by combining or rearranging smaller data elements that already exist within the system. The user can also introduce new data elements into the system.
[0020] In one implementation, the data sets in the system 100 include multiple text documents (e.g., text documents 105 , 110 , 115 ). Each text document is made up of numerous terms, each term being a word or phrase that describes a particular concept. For instance, in the example presented in FIG. 1 , document 105 is comprised of three terms 10 , 11 , 12 . Document 110 is also comprised of three terms 22 , 13 , 14 . In this instance, term 22 in document 110 refers to the same concept as term 12 in document 105 . Document 115 is comprised of three terms 10 , 22 , 15 .
[0021] FIG. 2 illustrates an example process 200 in which a user can associate a new or existing data element (e.g., the terms in documents 105 , 110 , and 115 ) with concepts so that data elements that describe the same concept can be associated with one another. First, the system receives user input that includes the data element under consideration, as well as the context in which the data element is being used (step 210 ). A context can include metadata that describes the data set. For example, the context can include the language of the data element and the version of the data element. In one implementation, it is the frontend system 125 that receives this user input from the user.
[0022] The system then sends the user input to the terminology database (step 220 ). In one implementation, the user input that has been received by the frontend system 125 is passed to the backend system 130 . The backend system 130 then queries the terminology database 135 with the context information, in order to determine if the specific context has already been created in conjunction with a previous data element.
[0023] The system then receives a list of matches from the terminology database (step 230 ). Based on the query submitted in step 220 , the terminology database 135 generates a listing of likely concepts that the data element is referencing. This list is returned to the backend system 130 , which passes the information to the frontend system 125 .
[0024] Each concept has assigned to it two globally unique identifiers (GUID). The first GUID is known as the concept globally unique identifier (cGUID), and the second GUID is known as the incarnation globally unique identifier (iGUID). The iGUID is unique to each data element, regardless of the context the data element is used in. The cGUID is shared by all data elements that refer to the same concept.
[0025] The system receives user input selecting the appropriate match from the list of matches (step 240 ). The user can view the list of matches that the terminology database 135 generated, in order to select the concept that correlates with the selected data element.
[0026] Finally, the system directly associates the cGUID and the iGUID of the data element with the data set (step 250 ). In one implementation, the GUIDs are directly linked with the data set through the use of markup language. For example, the data set can include markup language, attached to a specific data element, that identifies the iGUID and cGUID of that specific data element. The markup code may be in an extensible markup language (XML) file format. The cGUID and iGUID are linked together in the data set, and are also linked to the terminology database, so that the terminology database maintains a complete record of every concept (uniquely identified by its cGUID), as well as every data element that is associated with each unique concept (each data element being uniquely identified by its iGUID). By linking both the cGUID and iGUID to the specific data element, every data element associated with the concept represented by the cGUID can be identified by the system, without having to separately query the terminology database for each data element.
[0027] A given cGUID can be associated with more than one iGUID. For example, in document 105 , term 12 is associated with iGUID 42 , and cGUID 52 . In document 115 , term 22 refers to the same concept as term 12 . Therefore, term 22 is also associated with cGUID 52 . However, as every unique data element receives a unique iGUID, term 22 is associated with iGUID 46 , which is a GUID that uniquely identifies that particular data element.
[0028] The association of data elements with particular concepts can be used in a variety of situations. For example, as the description or definition of a specific data element changes, the system can identify every location that makes use of the concept and data element, and either automatically or at the users discretion update the existing data sets to reflect the new data element description or definition that more accurately describes the concept. For example, the concept ‘operating system’ may be defined, and the existing data element associated with ‘operating system’ is Microsoft Windows 98 . With the release of Microsoft Windows XP, the user may wish to update some or all of the data sets that include references to Windows 98 to now include Windows XP. Using the cGUID and iGUID, it is easy to identify every situation which makes reference to the concept of ‘operating system,’ and generate new documents which reflect the current usage of the data element Windows XP.
[0029] Continuing this example, it is possible to have multiple data elements assigned to a single concept. For example, the data element ‘OS X’ can also be associated with the concept ‘operating system.’ In this manner, the documents that currently exist containing details about Windows can easily be adapted to reflect use with the Mac OS X, by having the system identify every data set that references the concept ‘operating system’ by using the cGUID associated with this concept, and then either automatically replace every data element with the data element ‘OS X,’ or prompting the user as to whether each individual data element should be changed. As the data elements are modified, each new or modified data element is assigned a new iGUID, in order to differentiate the new or modified data element from the older data elements. In this manner, the new data elements can be stored by the system without necessitating the need to overwrite or delete the old data elements.
[0030] The iGUID/cGUID relationship can be used to generate other data sets for use in a specific environment or locality. For example, a bilingual glossary can be created by the system based upon the data elements that are contained in a given selection of data sets. The system uses the iGUIDs and cGUIDs to recognize the concepts that are associated with the given selection of data sets. The system can then identify the data elements contained in the selection of data sets for each concept, as well as the appropriate data elements reflecting each concept in the desired language, and link them in a new data set to contains a bilingual or multilingual glossary.
[0031] The ability to associate data elements with concepts, no matter the language that the data element happens to be in, can also provide for enhanced retrieval functionality. A user can enter a search term into the system. Instead of merely looking for matches to the search term entered, and returning the matches to the user, the system can identify possible concepts that the user is attempting to locate. Once these concepts, and their associated cGUIDs, are identified, the system can return matches to the user that include data sets in multiple languages, as well as data sets that are related to what the user was searching for, but do not explicitly contain the search term that the user had originally entered.
[0032] The inclusion of both cGUIDs and iGUIDs can aid in the identification of a particular revision of the data set. As the iGUID is unique to each data element, it will always be able to identify the specific version of the data set that is being accessed. As mentioned above, each modification of a particular data element results in the assignment of a new iGUID to that data element. Therefore, it is also possible to reconstruct data sets using older data elements that have since been updated by newer data elements.
[0033] The use of cGUIDs and iGUIDs also allows the system to more easily manage references and links between data elements. A link that points to a specific target data element contains both the cGUID and the iGUID of the target data element that the link points to. Therefore, the link is uniquely associated with one specific data element. Further, this structure enables the system to verify that the link is still valid; if the iGUID contained in the link is not the same as the iGUID of the target data element, the system will recognize that a problem exists, and can either attempt to automatically fix the broken link, or alert the user that a broken link exists.
[0034] In an additional implementation, the backend system can be the SAP Knowledge Provider. In this instance, the SAP Knowledge Provider works by querying the terminology database, such as SAPTerm, in order to determine if any new iGUIDs exist for a given cGUID. For example, the user may wish to generate a hypertext markup language (HTML) file from an XML file that already exists within the system. When the system is generating the HTML document, the SAP Knowledge Provider can query the terminology database to make sure that every data element for a specified concept (represented by a cGUID) is the most current available, or if there are new data elements (with new iGUIDs) that exist for any given cGUID.
[0035] The above-described techniques can be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or in combinations of them. The implementation can be as a computer program product, i.e., a computer program tangibly embodied in an information carrier, e.g., in a machine-readable storage device or in a propagated signal, for execution by, or to control the operation of, data processing apparatus, e.g., a programmable processor, a computer, or multiple computers. A computer program can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program can be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a communication network.
[0036] Method steps can be performed by one or more programmable processors executing a computer program to perform functions of the invention by operating on input data and generating output. Method steps can also be performed by, and apparatus can be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit). Modules can refer to portions of the computer program and/or the processor/special circuitry that implements that functionality.
[0037] Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. The essential elements of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto-optical disks, or optical disks. Information carriers suitable for embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in special purpose logic circuitry.
[0038] To provide for interaction with a user, the above described techniques can be implemented on a computer having a display device, e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, for displaying information to the user and a keyboard and a pointing device, e.g., a mouse or a trackball, by which the user can provide input to the computer (e.g., interact with a user interface element). Other kinds of devices can be used to provide for interaction with a user as well; for example, feedback provided to the user can be any form of sensory feedback, e.g., visual feedback, auditory feedback, or tactile feedback; and input from the user can be received in any form, including acoustic, speech, or tactile input.
[0039] The above described techniques can be implemented in a distributed computing system that includes a back-end component, e.g., as a data server, and/or a middleware component, e.g., an application server, and/or a front-end component, e.g., a client computer having a graphical user interface and/or a Web browser through which a user can interact with an example implementation, or any combination of such back-end, middleware, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication, e.g., a communication network. Examples of communication networks include a local area network (“LAN”) and a wide area network (“WAN”), e.g., the Internet, and include both wired and wireless networks.
[0040] The computing system can include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other.
[0041] The invention has been described in terms of particular embodiments, but other embodiments can be implemented and are within the scope of the following claims. For example, the operations of the invention can be performed in a different order and still achieve desirable results. In certain implementations, multitasking and parallel processing may be preferable. As another example, although the use of UI patterns has been described in connection with business objects and business data, patterns can be used with other types of objects and with data that is not business-related. | Methods and apparatus, including computer program products, for the identification of data elements. A user input is received, comprising a data element and a context in which the data element is being used. The user input is sent to a terminology database. A list of entries is received, each entry having a first unique identifier (UID) and a second UID. The first represents a concept associated with the data element, and the second represents a specific description of the concept associated with the data element. A user input is received selecting an entry. The UIDs corresponding to the selected entry are directly associated with the data set. In some implementations, directly associating the UIDs with the data set comprises generating markup code comprising the UIDs. The invention lays the groundwork for a more efficient solution for the features/requirements related to versioning, updating, and translation in the realm of hypertexts. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to input apparatuses and image forming apparatuses, and more particularly to an input apparatus that is used when a user inputs an instruction into a main apparatus. The present invention also relates to an image forming apparatus equipped with the input apparatus.
2. Description of the Related Art
An image forming apparatus, such as a copy machine or a printer, typically has an operating panel with a display unit. The display unit may display plural input keys that a user can use to enter an instruction for executing a job. The display unit may also display various other information, such as a status of the image forming apparatus or various messages to the user.
For example, Japanese Laid-Open Patent Application No. 2005-010394 discloses an image forming apparatus that determines an optimum operation position based on physical information about the user, such as his or her height or the use of a wheelchair. In this technology, the height of an operating unit including an operating panel and the height of the ejected-sheet tray are increased or decreased in a linked manner. However, because the image forming apparatus employs mechanical keys, those keys that are frequently used are liable to fail, in which case the entire operating panel needs to be replaced.
Japanese Laid-Open Patent Application No. 2007-219966 discloses a projection input apparatus capable of projecting a keyboard with an appropriate size under different conditions, such as the projected distance. The publication also discloses an information terminal equipped with such projection input apparatus. However, many of the modern image forming apparatuses have multiple functions and offer a wide variety of input items (input menu). Thus, the use of the projection input apparatus with the latest image forming apparatus leads to reduced operability.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an input apparatus and an image forming apparatus in which one or more of the problems of the related art are eliminated.
A more specific object of the present invention is to provide an input apparatus that is highly durable and offers excellent operability.
Another object of the present invention is to provide an image forming apparatus that is highly durable and offers excellent operability.
According to one aspect of the present invention, an input apparatus for enabling a user to enter an instruction into a main apparatus includes a table device having a table with a variable size; a projector unit configured to project an image of plural virtual keys that is adapted to the size of the table onto the table; a position detecting device configured to contactlessly detect position information about a finger of the user that is placed on the table; and a key detecting device configured to detect one of the plural virtual keys that corresponds to the position of the finger of the user detected by the position detecting device, based on information about the image of the plural virtual keys and a result of the detection made by the position detecting device.
According to another aspect of the present invention, an image forming apparatus for forming an image based on an instruction entered by a user includes the above input apparatus for enabling the user to enter the instruction, and a main apparatus for forming the image in accordance with the instruction entered by the user via the input apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects, features and advantages of the invention will be apparent to those skilled in the art from the following detailed description of the invention, when read in conjunction with the accompanying drawings in which:
FIG. 1 is a perspective view of a multifunction peripheral according to an embodiment of the present invention;
FIG. 2 shows a block diagram of the multifunction peripheral shown in FIG. 1 ;
FIG. 3A is a side view of an input unit of the multifunction peripheral, wherein a second table is retracted in a first table;
FIG. 3B is a side view of the input unit wherein the second table is drawn out of the first table;
FIG. 4 is a perspective view of an upper part of the multifunction peripheral, illustrating the second table in a retracted position;
FIG. 5 is a perspective view of the upper part of the multifunction peripheral, illustrating the second table in a drawn-out position;
FIG. 6 is a side view of the input unit of the multifunction peripheral, illustrating an arrangement of various units within the input unit;
FIG. 7 shows a structure of a projector unit of the multifunction peripheral according to the present embodiment;
FIG. 8A is a side view of the input unit illustrating a projected region when the second table is retracted in the first table;
FIG. 8B shows a virtual key image projected in the projected region shown in FIG. 8A ;
FIG. 9A is a side view of the input unit illustrating the projected region when the second table is drawn out;
FIG. 9B shows a virtual key image projected in the projecting region shown in FIG. 9A ;
FIG. 10A is a side view of the input unit, illustrating an operation of an infrared device;
FIG. 10B shows how the projected region is covered by infrared light emitted by the infrared device;
FIG. 11 is a side view illustrating an operation of a CMOS camera in the input unit of the multifunction peripheral;
FIG. 12 shows a flowchart of an operation of an ADF/scanner unit control unit of the multifunction peripheral according to the present embodiment;
FIG. 13 shows a first half of a flowchart of an key input operation performed by a main body control unit;
FIG. 14 shows a latter half of the flowchart of the key input operation;
FIG. 15 shows a first half of a flowchart of an operation of the input unit control unit;
FIG. 16 shows a latter half of the flowchart of the operation of the input unit control unit;
FIG. 17 is a perspective view of the multifunction peripheral according to the present embodiment, illustrating the second table being retracted in the first table;
FIG. 18 is a perspective view of the multifunction peripheral, illustrating a virtual key image projected on the first table;
FIG. 19 is a perspective view of the multifunction peripheral, illustrating the second table being drawn out of the first table; and
FIG. 20 is a perspective view of the multifunction peripheral, illustrating a virtual key image being projected on the first and the second tables.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereafter, embodiment of the present invention are described with reference to FIGS. 1 through 20 . FIG. 1 shows a multifunction peripheral 100 as an image forming apparatus according to an embodiment of the present invention. FIG. 2 shows a block diagram illustrating the control relationships among various units of the multifunction peripheral 100 . The arrows shown in FIG. 2 indicate the general flow of representative signals or information and not the entire connection relationships among all of the blocks.
The multifunction peripheral 100 includes an input unit 107 ; an ADF (automatic document feeder)/scanner unit 118 ; a projection table unit 108 ; a printer 105 ; a sheet tray 106 ; an ejected-sheet tray 104 ; a user sensor 114 ; an operating panel display unit 102 ; an ID reader 123 ; a memory 124 ; and a main body control unit 115 .
The input unit 107 includes a projector unit 109 ; a CMOS (complementary metal-oxide semiconductor) camera 110 ; an infrared device 111 ; and an input unit control unit 116 .
The ADF/scanner unit 118 includes an ADF 101 , which is an automatic manuscript transport device; an ADF lift sensor 121 ; a manuscript sensor 122 ; a scanner 103 ; and an ADF/scanner unit control unit 120 .
The ADF 101 is disposed at the top of the multifunction peripheral 100 , above the scanner 103 (on a +Z side). The ADF 101 includes a manuscript tray on which one or more sheets of a manuscript can be set. The ADF 101 transports the manuscript set on the manuscript tray onto an upper surface (which may be a glass surface) of the scanner 103 , one sheet at a time.
The manuscript sensor 122 is a sensor for detecting whether a manuscript is set on the manuscript tray of the ADF 101 . The manuscript sensor 122 supplies an output signal to the ADF/scanner unit control unit 120 .
The ADF 101 can be separated from the scanner 103 . Specifically, the ADF 101 is fixed on its +X end alone in such a manner that the ADF 101 can be rotated about an +X end axis by raising the −X end of the ADF 101 . Thus, when copying a bound manuscript, for example, the ADF 101 can be lifted from the scanner 103 allowing the manuscript to be placed on the upper surface of the scanner 103 .
The ADF lift sensor 121 is a sensor for detecting whether the ADF 101 is lifted from the scanner 103 . The ADF lift sensor 121 supplies an output signal to the ADF/scanner unit control unit 120 .
The ADF/scanner unit control unit 120 controls the ADF 101 and the scanner 103 based on the output signals from the manuscript sensor 122 and the ADF lift sensor 121 , as well as an instruction from the main body control unit 115 .
The scanner 103 reads image information in the manuscript placed on its upper surface. When the multifunction peripheral 100 functions as a copy machine, the image information read is sent to the printer 105 . The image information may be sent directly from the scanner 103 to the printer 105 ; or it may be sent to the printer 105 via the ADF/scanner unit control unit 120 or the main body control unit 115 . When the multifunction peripheral 100 functions as a scanner, the image information thus read may be stored in the memory 124 . In this case, the image information may be sent directly from the scanner 103 to the memory 124 , or via the ADF/scanner unit control unit 120 or the main body control unit 115 .
The user sensor 114 is a sensor for detecting whether there is a user at the front (i.e., on the −X side) of the multifunction peripheral 100 . The user sensor 114 supplies an output signal to the main body control unit 115 .
The operating panel display unit 102 displays various messages or the like based on an instruction from the main body control unit 115 .
The ID reader 123 is used by the user when entering a user ID. Upon entry of the user ID, the main body control unit 115 is notified of the user ID. The user ID may be entered either by a key input method or via a card reader reading an ID card in a contacted or contactless manner.
The memory 124 stores user information including information about virtual keys for each user ID. The sheet tray 106 stores printing sheets.
When the multifunction peripheral 100 functions as a copy machine, the printer 105 takes out one of the printing sheets from the sheet tray 106 and may then print the image information read by the scanner 103 on the printing sheet. When the multifunction peripheral 100 functions as a printer, the printer 105 may print image information transmitted from a higher-level device (such as a personal computer). The printing sheet with the image information printed thereon is ejected onto the ejected-sheet tray 104 .
The projection table unit 108 is disposed on the front side of the multifunction peripheral 100 and is positioned so that a standing user can easily place his or her finger on the projection table unit 108 .
In accordance with the present embodiment, as shown in FIGS. 3A and 3B , the projection table unit 108 includes a first table 108 a having an internal space; a second table 108 b that can be housed within the first table 108 a ; and a table drive unit 129 configured to drive the second table 108 b in the X axis direction. The first table 108 a and the second table 108 b may be collectively referred to as “the table”.
The second table 108 b has a protrusion 126 at the +X end on the −Y side. At both ends within the first table 108 a in the Y axis direction, rails 125 extend in the X axis direction. The second table 108 b rests on the rails 125 .
Further, at the −Y side of the first table 108 a , there are disposed a first protrusion sensor 128 a on the −X end and a second protrusion sensor 128 b on the +X end. These protrusion sensors 128 a and 128 b detect a contact of the protrusion 126 of the second table 108 b therewith at the respective ends of the first table 108 a.
When the second table 108 b is drawn out of the first table 108 a , the protrusion 126 of the second table 108 b contacts the protrusion sensor 128 a at a predetermined drawn-out position. When the second table 108 b is put back into the first table 108 a , the protrusion 126 contacts the protrusion sensor 128 b at a predetermined housed position. Each of the protrusion sensors supplies an output signal to the input unit control unit 116 .
The second table 108 b is driven by the table drive unit 129 in accordance with an instruction from the input unit control unit 116 . Thus, in the projection table unit 108 , the available size of the table can be changed, as shown in FIGS. 4 and 5 , for example.
The input unit 107 is disposed on the +X side of the projection table unit 108 . The projector unit 109 , the CMOS camera 110 , and the infrared device 111 may be retained within the casing of the input unit 107 in a predetermined positional relationship, as shown in FIG. 6 .
In the illustrated example, the projector unit 109 is disposed at the +Z end in the casing of the input unit 107 . The projector unit 109 includes a projector 109 a and a projection drive mechanism 109 b . The projector 109 a projects a virtual key image on the table of the projection table unit 108 . The projection drive mechanism 109 b can rotate the projector 109 a in order to change the size of a region (which may be hereafter referred to as a “projected region”) on the table in which the virtual key image is projected.
With reference to FIG. 7 , the projector 109 a includes a light source unit 109 a 1 , a collimating optical system 109 a 2 , an integrator optical system 109 a 3 , a liquid crystal panel 109 a 4 , and a projection lens 109 a 5 .
The light source unit 109 a 1 outputs light that is incident on the liquid crystal panel 109 a 4 via the collimating optical system 109 a 2 and the integrator optical system 109 a 3 . The light incident on the liquid crystal panel 109 a 4 is modulated in accordance with projection image data and then enlarged and projected by the projection lens 109 a 5 onto the table. The lenses in the optical system are adjusted to minimize distortion or blurring in the image projected on the table.
FIG. 8A shows the projected region when the second table 108 b is housed within the first table 108 a . FIG. 8B shows an example of the virtual key image projected in the projected region of FIG. 8A . FIG. 9A shows the projected region when the second table 108 b is drawn out of the first table 108 a . FIG. 9B shows an example of the virtual key image projected in the projected region shown in FIG. 9A .
The individual virtual keys in the virtual key images shown in FIGS. 8B and 9B are similar in meaning to the input keys in a conventional multifunction peripheral apparatus. For example, the “Copy” key is a virtual key for instructing an operation of the multifunction peripheral as a copy machine. The “Scanner” key is a virtual key for instructing an operation as a scanner. The “Printer” key is a virtual key for instructing an operation as a printer. The “Fax” key is a virtual key for instructing an operation as a facsimile machine.
The “Reset” key is a virtual key for cancelling the previously entered contents. The “Start” key is a virtual key for instructing the start of an operation. The “Stop” key is a virtual key for instructing the ceasing of an operation. The “0” through “9” keys, the “./*” key, and the “#” key are virtual keys corresponding to the so-called numeric keypad. The “UserTool” key is a virtual key for entering into a mode for viewing the initial settings of the multifunction peripheral 100 or a counter value. The “Expansion” key is a virtual key for changing the size of the table. The “Function1” through “Function11” keys are virtual keys for opening a document box (for storage of documents), login or logout, and various other functions.
Referring to FIGS. 6 and 10A , the infrared device 111 is disposed on the −Z end of the casing of the input unit 107 . The infrared device 111 includes a light source 111 a for emitting infrared light, and a reflecting mirror 111 b for bending the optical path of the infrared light from the light source 111 a . As shown in FIG. 10A , the infrared light, after being emitted by the light source 111 a in the −Z direction, has its optical path bent by the reflecting mirror 111 b in the −X direction. Because the infrared light emitted by the light source 111 a is diverging light, the infrared light propagates in a space close to the surface of the table while diverging in directions parallel to the table surface. The infrared light from the input unit 107 may cover most of the projected region as seen from the Z axis direction, as shown in FIG. 10B .
With reference to FIG. 11 , the CMOS camera 110 is disposed between the projector unit 109 and the infrared device 111 within the casing of the input unit 107 . The CMOS camera 110 is positioned such that, when a finger 130 of the user is placed on the table as shown in FIG. 11 , the infrared light reflected by the finger 130 becomes incident on the CMOS camera 110 . Upon incidence of the infrared light, the CMOS camera 110 outputs a signal including information about the position of the finger 130 . The output signal from the CMOS camera 110 is supplied to the input unit control unit 116 .
The ADF/scanner unit control unit 120 include a CPU and a memory (both not shown) in which a program described in codes that the CPU 120 a can decode and various data are stored. Hereafter, an operation of the ADF/scanner unit control unit 120 is described with reference to a flowchart shown in FIG. 12 . The operation is performed in accordance with a process algorithm of the program executed by the CPU.
When power is turned on, a start address of the program is set in a program counter of the CPU, and the process starts.
Communications with the main body control unit 115 are conducted via interrupt processes for both transmission and reception (i.e., via a reception interrupt process and a transmission interrupt process). Upon notice from the main body control unit 115 , a corresponding reception flag is set in the reception interrupt process.
Referring to FIG. 12 , in the initial step S 401 , an output signal is acquired from the ADF lift sensor 121 .
In step S 403 , based on the output signal from the ADF lift sensor 121 , it is determined whether the ADF 101 is lifted by the user. If the ADF lift sensor 121 detects the lifting of the ADF 101 , the process goes to step S 405 .
In step S 405 , the main body control unit 115 is notified of the lifting of the ADF 101 .
In step S 407 , an output signal is acquired from the manuscript sensor 122 .
In step S 409 , it is determined whether, based on the output signal from the manuscript sensor 122 , a manuscript is set on the manuscript tray of the ADF 101 . If the manuscript sensor 122 detects the setting of the manuscript, the process goes to step S 411 .
In step S 411 , the main body control unit 115 is notified of the setting of the manuscript.
In step S 413 , reference is made to the reception flag in order to determine whether a scan request has been made by the main body control unit 115 . When there is a scan request from the main body control unit 115 , the process goes to step S 415 . At the same time, the reception flag indicating the scan request from the main body control unit 115 is reset.
In step S 415 , it is determined whether, based on the output signal from the ADF lift sensor 121 , the ADF 101 is lifted by the user. If the ADF lift sensor 121 detects no lifting of the ADF 101 , the process goes to step S 417 .
In step S 417 , the ADF 101 is instructed to start operating, whereby the manuscript set on the manuscript tray is transported onto the upper surface of the scanner 103 . When there are more than one sheet of manuscript, the reading of the initially transported manuscript sheet by the read scanner 103 is completed before the next manuscript sheet is transported to the scanner 103 .
In step S 419 , the scanner 103 is instructed to start operating, whereby the image information in the manuscript placed on the upper surface is read. When all of the manuscript sheets have been read, the process returns to step S 401 .
In step S 403 , if the ADF lift sensor 121 detects no lifting of the ADF 101 , the process goes to step S 407 . In step S 409 , if the manuscript sensor 122 detects no setting of the manuscript, the process goes to step S 413 . In step S 413 , if there is no scan request from the main body control unit 115 , the process goes back to step S 401 . In step S 415 , if the ADF lift sensor 121 detects the lifting of the ADF 101 , the process goes to step S 419 .
The main body control unit 115 includes a CPU and a memory (both not shown) in which a program written in codes that can be decoded by the CPU 115 a and various data are stored. Hereafter, a key input operation performed by the main body control unit 115 is described with reference to a flowchart shown in FIGS. 13 and 14 . The flowchart shown in FIGS. 13 and 14 corresponds to a process algorithm executed by the CPU in accordance with the program in the memory.
When power is turned on, a start address of the program is set in the program counter of the CPU, whereby an operation of the main body control unit 115 is started. When the key input operation is requested, the program corresponding to the flowchart of FIGS. 13 and 14 (which may be a subroutine or a module) is called.
Communications with the input unit control unit 116 , the ADF/scanner unit control unit 120 , and the ID reader 123 are conducted via interrupt processes for both transmission and reception (i.e., a reception interrupt process and a transmission interrupt process). Upon notice from either the input unit control unit 116 , the ADF/scanner unit control unit 120 , or the ID reader 123 , a corresponding reception flag is set in the reception interrupt process.
In the initial step S 501 , a timer counter A is reset. The timer counter A is counted up by the timer interrupt process.
In step S 503 , an output signal is acquired from the user sensor 114 .
In step S 505 , based on the output signal from the user sensor 114 , it is determined whether the user sensor 114 has detected a user. If not, the process goes to step S 507 .
In step S 507 , reference is made to the reception flag to determine whether the ADF 101 is being lifted. Unless there is a notification from the ADF/scanner unit control unit 120 that the ADF 101 is lifted, the process goes to step S 509 .
In step S 509 , reference is made to the reception flag to determine whether a manuscript is set in the manuscript tray of the ADF 101 . Unless there is a notification from the ADF/scanner unit control unit 120 that a manuscript is set, the process goes to step S 511 .
In step S 511 , reference is made to the timer counter A to determine whether a time-out duration has run out. If the value of the timer counter A is below a predetermined value, the process goes back to step S 503 .
On the other hand, if in step S 505 the user sensor 114 indicates a detection, the process goes to step S 513 .
In step S 507 , if there is the notification from the ADF/scanner unit control unit 120 that the ADF 101 is lifted, the process goes to step S 513 . At the same time, the reception flag indicating the lifting of the ADF 101 is reset.
In step S 509 , if there is the notification from the ADF/scanner unit control unit 120 that the manuscript is set, the process goes to step S 513 . At the same time, the reception flag indicating the setting of the manuscript is reset.
In step S 513 , a message requesting the input of a user ID is displayed on the operating panel display unit 102 .
In step S 515 , a timer counter B is reset. The timer counter B is counted up by the timer interrupt process.
In step S 517 , reference is made to the reception flag to determine whether the user ID has been entered. If there is no notice of the user ID from the ID reader 123 , the process goes to step S 519 .
In step S 519 , reference is made to the timer counter B to determine whether the time-out duration has run out. If the value of the timer counter B is below a predetermined value, the process goes back to step S 517 . If the value of the timer counter B exceeds the predetermined value, the process goes back to step S 501 .
In step S 517 , if there is the notification from the ID reader 123 about the user ID, the process goes to step S 551 . The reception flag indicating the notification of the user ID is also reset.
In step S 551 , reference is made to the user information stored in the memory 124 , and the virtual key information corresponding to the indicated user ID is acquired. The virtual key information may include a virtual key number that specifies the kind and arrangement of the virtual keys and the size of each of the keys, and the presence or absence of the second table 108 b.
In step S 553 , the input unit control unit 116 is notified of the virtual key information acquired.
In step S 555 , a message is displayed on the operating panel display unit 102 indicating that a key input can be made.
In step S 557 , it is determined whether a notification is received from the input unit control unit 116 indicating the running out of the time-out duration. If not, the process goes to step S 559 .
In step S 559 , it is determined whether there is a notification of key data from the input unit control unit 116 . If not, the process goes to step S 563 .
In step S 563 , an output signal from the user sensor 114 is acquired.
In step S 565 , it is determined whether, based on the output signal from the user sensor 114 , the user sensor 114 has detected a user. If not, the process goes to step S 567 .
In step S 567 , the process waits for a predetermined time.
In step S 569 , an output signal from the user sensor 114 is again acquired.
In step S 571 , based on the output signal from the user sensor 114 , it is determined whether the user sensor 114 has detected a user. If not, the process goes to step S 573 .
In step S 573 , it is determined that the key input operation should be terminated, and the input unit control unit 116 is notified of the end of key input. This completes the key input operation, and the system may transition to another process or operation.
In step S 511 , if the value of the timer counter A exceeds the predetermined value, the process goes to step S 573 .
In step S 557 , if there is the notification from the input unit control unit 116 about the time-out, the process goes back to step S 501 . The reception flag indicating the time-out notification is also reset.
In step S 565 , if the user sensor 114 indicates the detection of a user, the process goes back to step S 557 .
Similarly, in step S 571 , if the user sensor 114 indicates the detection of a user, the process goes back to step S 557 .
In step S 559 , if there is the notification of key data from the input unit control unit 116 , the process goes to step S 575 . The reception flag indicating the key data notification is also reset.
In step S 575 , it is determined whether the key data indicates the “Start” key. If the key data corresponds to the “Start” key, the process goes to step S 577 .
In step S 577 , it is determined whether a manuscript needs to be scanned. For example, when the multifunction peripheral 100 is set to operate as a copy machine or a scanner, the process goes to step S 579 .
In step S 579 , a scan request is sent to the ADF/scanner unit control unit 120 .
In step S 581 , a condition setting process or any other process in accordance with the key data is performed. The process then goes back to step S 557 .
In step S 575 , if the key data does not correspond to the “Start” key, the process goes to step S 581 . In step S 581 , when the key data corresponds to the “Copy” key, the multifunction peripheral 100 is set to operate as a copy machine. When the key data corresponds to the “Scanner” key, the multifunction peripheral 100 is set to operate as a scanner. When the key data corresponds to the “Printer” key, the multifunction peripheral 100 is set to operate as a printer.
In step S 577 , when the multifunction peripheral 100 is set to operate as a printer, for example, the process goes to step S 581 .
The input unit control unit 116 includes a CPU and a memory (both not shown) in which a program written in codes that can be decoded by the CPU and various data are stored. Hereafter, an operation of the input unit control unit 116 is described with reference to a flowchart shown in FIGS. 15 and 16 . The flowchart of FIGS. 15 and 16 corresponds to a process algorithm executed by the CPU of the input unit control unit 116 in accordance with the program in the memory.
When power is turned on, a start address of the program is set in a program counter of the CPU, whereby the process is started.
In the present example, communications with the main body control unit 115 are conducted via interrupt processes for both transmission and reception (i.e., a reception interrupt process and a transmission interrupt process). Upon notification from the main body control unit 115 , a corresponding reception flag is set in the reception interrupt process.
In the initial step S 601 , reference is made to the reception flag to determine whether there is a notification from the main body control unit 115 concerning virtual key information. If there is the virtual key information notification from the main body control unit 115 , the process goes to step S 603 . The reception flag indicating the notification of virtual key information is also reset.
In step S 603 , various information is identified based on the virtual key information, such as the kind and arrangement of the virtual keys, the size of each virtual key, and the presence or absence of the second table 108 b . In the present example, the memory stores projection data for each virtual key number in advance, the data including the kind and arrangement of the virtual keys, the size of each virtual key, and the presence or absence of the second table 108 b . Thus, the virtual key number enables the retrieval and extraction of relevant projection data.
In step S 605 , based on the acquired projection data, it is determined whether the second table 108 b in the projection table unit 108 is required. If not, the process goes to step S 607 .
In step S 607 , the table drive unit 129 is instructed to retract the second table 108 b into the first table 108 a (see FIG. 17 ). The second table 108 b may be moved in the +X direction until the protrusion 126 of the second table 108 b contacts the protrusion sensor 128 b . When the second table 108 b is already retracted in the first table 108 a , no operation is performed.
In step S 609 , the projection drive mechanism 109 b is instructed to set the size of the projected region on the table to “Small”.
In step S 615 , based on the projection data, projection image data is outputted to the projector unit 109 .
In step S 617 , the projector unit 109 is instructed to perform projection. Thus, a virtual key image is projected on the first table 108 a as shown in FIG. 18 .
In step S 619 , the infrared device 111 is instructed to emit infrared light.
In step S 621 , the CMOS camera 110 is turned on, and the key finalizing flag is reset.
In step S 623 , a timer counter A is reset. The timer counter A is counted up by the timer interrupt process.
In step S 625 , based on the output signal from the CMOS camera 110 , it is determined whether the CMOS camera 110 has received reflected light of the infrared light. If the CMOS camera 110 has received the reflected light of the infrared light, the process goes to step S 627 .
In step S 627 , reference is made to the timer counter A to determine whether the time-out duration has run out. If the value of the timer counter A is below a predetermined value, the process returns to step S 625 . On the other hand, if the value of the timer counter A exceeds the predetermined value, the process goes to step S 629 .
In step S 629 , the main body control unit 115 is notified of the running out of the time-out duration. Then, the process returns to step S 601 .
In step S 601 , if there is no notification from the main body control unit 115 concerning the virtual key information, the process waits until the notification about the virtual key information is received from the main body control unit 115 .
In step S 605 , if the second table 108 b is required, the process goes to step S 611 .
In step S 611 , the table drive unit 129 is instructed to draw out the second table 108 b from the first table 108 a (see FIG. 19 ). In the present example, the second table 108 b is moved in the −X direction until the protrusion 126 of the second table 108 b contacts the protrusion sensor 128 a . When the second table 108 b is already drawn out of the first table 108 a , no operation is performed.
In step S 613 , the projection drive mechanism 109 b is instructed to set the size of the projected region on the table to “Large”. Then, the process goes to step S 615 . At this time, a virtual key image is projected on the first table 108 a and the second table 108 b in step S 617 , as shown in FIG. 20 , for example.
In step S 625 , if the CMOS camera 110 receives the reflected light of infrared light, the process goes to step S 651 .
In step S 651 , based on the output signal from the CMOS camera 110 , a position at which the reflected light is received on the CMOS camera 110 is determined.
In step S 653 , the process waits for a predetermined time.
In step S 655 , based on the output signal from the CMOS camera 110 , the position at which the reflected light is received on the CMOS camera 110 is again determined.
In step S 657 , it is determined whether the reflected light reception position determined in step S 651 is the same as the reflected light reception position determined in step S 655 . If the reception positions are the same, the process goes to step S 659 . The reception positions may be considered the same if the difference between them is within a predetermined range.
In step S 659 , reference is made to the projection data, and key data corresponding to the reflected light reception position is searched for.
The relationship between the various reflected light reception positions on the CMOS camera 110 and the corresponding positions of the finger on the table is acquired in advance through various preliminary experiments. Information concerning the relationship is stored in the memory of the input control unit. Thus, the position of the finger on the table can be known from the reflected light reception position on the CMOS camera 110 . Further, the kind of the virtual key projected at the position of the finger can be known from the position of the finger on the table and the projection data.
In step S 661 , it is determined whether there is key data corresponding to the reception position of the reflected light. If there is the corresponding key data, the process goes to step S 663 .
In step S 663 , if the key finalizing flag is in a reset status, the main body control unit 115 is notified of the key data corresponding to the reception position of the reflected light, and the key finalizing flag is set.
In step S 665 , reference is made to the reception flag to determine whether there is a notification from the main body control unit 115 indicating the end of key input. If not, the process returns to step S 623 .
In step S 657 , if the respective reception positions are different, the process returns to step S 623 , and the key finalizing flag is reset.
In step S 661 , if there is no key data corresponding to the reception position of the reflected light, the process returns to step S 623 , and the key finalizing flag is reset.
In step S 665 , if there is the notification indicating the end of key input, the process proceeds to step S 667 . The reception flag indicating the notification of the end of key input is also reset.
In step S 667 , the projector unit 109 is instructed to stop projecting.
In step S 669 , the infrared device 111 is instructed to stop emitting infrared light.
In step S 671 , the CMOS camera 110 is turned off, and the process returns to step S 601 .
Thus, in accordance with the multifunction peripheral 100 of the present embodiment, the input apparatus includes the projection table unit 108 , the input unit 107 , and the ID reader 123 . The position detecting device includes the infrared device 111 , the CMOS camera 110 , and the input unit control unit 116 . The key detecting device includes the input unit control unit 116 . The user information input unit includes the ID reader 123 .
As described above, the multifunction peripheral 100 according to the present embodiment includes the projection table unit 108 having a table whose size can be changed; the projector unit 109 for projecting an image of plural virtual keys on the table, the keys corresponding to the size of the table; the infrared device 111 for emitting infrared light near a region on the table where the image of the plural virtual keys is projected; the CMOS camera 110 on which infrared light reflected by the finger of a user placed on the table is incident and that outputs a signal including position information about the finger of the user on the table; and the input unit control unit 116 for detecting one of the plural virtual keys that corresponds to the position of the user's finger, based on the information about the image of the plural virtual keys and the output signal from the CMOS camera 110 .
In accordance with the present embodiment, the user can input an instruction to the multifunction peripheral main body non-mechanically, so that the durability of the input apparatus or the multifunction peripheral can be improved. Further, because the size of the table can be changed as needed, enhanced operability can be obtained.
In accordance with the foregoing embodiment, the key input operation is started by the main body control unit 115 when the user either stands in front of the multifunction peripheral 100 , sets a manuscript, or performs a preliminary operation (preparatory operation) for the setting of the manuscript, for example. Thus, the input unit 107 can activate the projector unit 109 , the CMOS camera 110 , or the infrared device 111 only when necessary, thereby contributing to the saving of energy.
In the foregoing embodiment, because the plural virtual keys corresponding to the user ID are projected, further enhanced operability can be obtained.
In an embodiment of the present invention, at least part of the process performed by the input unit control unit 116 may be implemented by hardware. At least part of the key input operation performed by the main body control unit 115 may be performed by the input unit control unit 116 . For example, the process of acquiring the virtual key information corresponding to the user ID may be performed by the input unit control unit 116 .
At least part of the key input operation performed by the main body control unit 115 may be performed by hardware. At least part of the process performed by the ADF/scanner unit control unit 120 may be performed by the main body control unit 115 or other hardware.
While in the foregoing the second table 108 b is described as being drawing in and out mechanically by the table drive unit 129 , the second table 108 b may be drawn in or out by the user manually. The size of the table is not limited to the two sizes described above, and there may be three or more sizes of the table so that the second table 108 b can be drawn in or out in multiple steps.
While the virtual key information is described above as being different from one user to another, the present invention is not limited to such embodiment. In another embodiment, the virtual key information may be varied depending on the size of the table. In this case, after the second table 108 b is drawn in or out manually, the virtual key information may be acquired in accordance with the position of the second table 108 b (in the X axis direction).
While the user ID is entered using the ID reader 123 in the foregoing embodiment, the present invention is not limited to such an embodiment. In another embodiment, information identifying virtual key information may be entered using the ID reader 123 . For example, the virtual key number may be entered using the ID reader 123 .
The user ID may be entered in other ways than using the ID reader 123 . For example, the user ID may be entered via a higher-level apparatus (such as a personal computer).
In the foregoing description, the main body control unit 115 has been described as transitioning to a next operation (i.e., in step S 513 in the present embodiment) upon detection of any of the events of detection of a user, the lifting of the ADF, or the setting of a manuscript during the key input operation. However, the present invention is not limited to such an embodiment. In another embodiment, the main body control unit 115 may transition to the next operation upon detection of a combination of the presence of the user and either the lifting of the ADF or the setting of the manuscript.
While the size of the projected region has been described as being changed using the projection drive mechanism 109 b , the present invention is not limited to such an embodiment. In another embodiment, instead of the projection drive mechanism 109 b , an aperture mechanism 109 a 6 may be used that has plural apertures with different opening sizes. Then, an appropriate aperture corresponding to the size of the projected region can be disposed on the optical path (such as after the projection lens 109 a 5 ). In another embodiment, the liquid crystal panel 109 a 4 may be provided with an aperture function by incorporating mask data corresponding to the size of the projected region into the projection image data.
The kind, arrangement, and size of the virtual keys projected on the table in the foregoing embodiment are merely examples and the present invention is not limited to such an embodiment. The color of the virtual keys may be varied depending on the kind of the key. In this case, a color liquid crystal panel may be used instead of the liquid crystal panel 109 a 4 .
While the foregoing embodiment has been described with reference to a multifunction peripheral as an example of image forming apparatus, the present invention is not limited to the multifunction peripheral. For example, the image forming apparatus may be a copy machine, or any other image forming apparatus configured to form an image based on an instruction entered by the user.
Thus, the input apparatus according to an embodiment of the present invention can be suitably used by a user for entering an instruction into an apparatus main body. The image forming apparatus according to an embodiment of the present invention can be suitably used for forming an image based on an instruction entered by the user.
Although this invention has been described in detail with reference to certain embodiments, variations and modifications exist within the scope and spirit of the invention as described and defined in the following claims.
The present application is based on the Japanese Priority Application No. 2008-158739 filed Jun. 18, 2008, the entire contents of which are hereby incorporated by reference. | An input apparatus for enabling a user to enter an instruction into a main apparatus has high durability and offers superior operability. The input apparatus includes a table device having a table with a variable size. An image of plural virtual keys that is adapted to the size of the table is projected by a projector unit onto the table. Position information about a finger of the user that is placed on the table is detected by a position detecting device contactlessly. One of the plural virtual keys that corresponds to the position of the finger of the user detected by the position detecting device is detected by a key detecting device based on information about the image of the plural virtual keys and a result of the detection made by the position detecting device. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the insulation of structures and similar insulation applications and more particularly, to insulation configurations for ceiling and floor structures. Through extensive tests, it has surprisingly been determined that the efficiency of low density, loose-fill , particulate, blown insulation, as well as low density fiber batt insulation, is greatly improved by placing additional similarly constituted high density insulation containing fiberglass or other insulation, over and under the low density insulation, depending upon the attic or floor application, to isolate the low density insulation and produce layered high density-low density insulation configurations of surprisingly high efficiency.
Recent extensive tests and studies have determined that current test methods for measuring the efficiency of insulation do not accurately predict the "in place performance" of low density fiber, loose-fill, particulate, blown insulation. The three current test methods commonly used in the industry to measure performance of insulation are the "Guarded Hot Plate", "Guarded Hot Box" and the "Calibrated Hot Box" techniques. All three test methods induce heat on one side of the insulation while the insulation is contained and not exposed to the atmosphere and measure the heat which passes through the insulation. From these tests, a thermal conductivity coefficient, (K) is determined and this thermal conductivity coefficient is used to calculate the thermal resistance, (R) of the insulation. These data are then used by architects and engineers to design and predict the thermal efficiency of structures.
2. Description of the Prior Art
In the construction of homes, buildings and other structures, wall configurations are typically assembled from vertical studs and insulation is placed between the studs. It is generally assumed that this insulation prevents air circulation between the studs. However, in contradiction to this technology, conventional wall construction provides for "weep" or ventilation holes at the bottom of the wall and the insulation is thusly vented to the attic, to permit the wall to "breathe". The discoveries outlined in this application make it reasonable to assume that this "breathing" of the wall deteriorates the efficiency of the insulation to a degree much greater than expected. The "breathing", or heat-induced natural convection, also exists in the low density, loose-fill particulate or fiber batt insulation in attics and under floors and can be reduced by placing high density horizontal batt or pillow insulation barriers over or under the low density insulation, to seal the insulation from convection and create high efficiency, layered insulation configurations characterized by closed cells within the attic and floor structures. The teachings of this invention thus dictate that the first reason these layered insulation configurations are more thermally efficient, is that air is more easily trapped in the low density insulation layer. Secondly, the high density-low density layers combine in a synergistic manner to create more efficiency than is possible in a homogeneous layer of insulation of the same thickness. Consequently, according to a preferred embodiment of this invention, the layers of insulation are combined to incorporate a first layer of fibrous, loose-fill, particulate, blown insulation of high density over or under a low density insulation layer, depending upon location, to provide more thermally efficient insulation configurations.
In order to better understand the phenomena which take place in the insulation configurations of this invention, a highly effective apparatus was designed for conducting tests which accurately measure and predict the "in place performance" of fiber insulation layered according to this invention in building structures. The test results are outlined in FIG. 6 of the drawings.
Various types of insulation configurations have been patented over the years. Typical of these insulation configurations is the "Wall Insulation" detailed in U.S. Pat. No. 2,283,257, dated May 19, 1942, to M. A. Jorsch. The wall insulation includes inner and outer sheets of cellular fiberboard located within a wall to form a chamber between the sheets, which chamber acts as a dead air space and increases the insulation efficiency of the wall. U.S. Pat. No. 2,804,657, dated Sep. 3, 1957, to C. G. Munters, details "Heat Insulated Walls of Cold-Storage Rooms." The heat insulated walls include a spaced outer casing and an inner lining, with a diffusion barrier located adjacent to the casing on the iiner side and further including heat insulating material located between the casing and the lining. U.S. Pat. No. 4,047,346, dated Sep. 13, 1977, to Robert J. Alderman, details a "Chicken Wire Roof and Method of Insulation". An insulated roof structure is formed on the industrial building by mounting a support framework on the purlins in the partially completed roof structure and moving the framework along the length of the purlins. A reel of wire mesh and a reel of sheet material are carried by the framework over each of the spaces between adjacent ones of the purlins and as the reels are progressively unrolled, layers of wire mesh and sheet material are applied to the spaces between the purlins while the support framework moves. Additional insulation can be blown upon or otherwise applied to the sheet material to fill the spaces between the purlins and hard sheets of roofing material are applied to the purlins as the support framework progresses across the structure. U.S. Pat. No. 4,696,138, dated Sep. 29, 1987, to Christopher A. Bullock, details "InsulationConfigurations and Method of Increasing Insulation Efficiency". Insulation configurations for the ceiling, floor and walls of structures include at least one layer of particulate or "blown" insulation, with a water vapor-permeable film or films isolating the layer or layers to limit air circulation and infiltration through the layers. Multi-layered insulation batts for building structures are detailed in U.S. Pat. No. 4,700,521, dated Oct. 20, 1987, to Craig H. Cover. The patent details thermal insulation for walls, ceilings and floors of building structures, which insulation contains alternating layers of low emissivity sheets and batts of low heat conductive material, laminated to form a single insulation batt. A "Method and Apparatus for Installing Insulation" is detailed in U.S. Pat. No. 4,724,651, dated Feb. 16, 1988, to Robert E. Fligg. Multiple sheets of vinyl-backed, fiberglass insulation are fastened side-by-side to each other to cover the area to be insulated. Purlin clips having an aperture therein are used to thread a band of metal therethrough for supporting the bottom side of the vinyl sheets at even intervals along their lengths.
It is an object of this invention to provide new and improved insulation configurations for insulating the attics and floors of homes, offices, and other structures, which insulation configurations are characterized by a first batt or particulate insulation layer of high density capping a second mass of low density, particulate insulation and resting on the ceiling in the attic and between floor joists, respectively, which high density insulation serves to isolate the low density particulate insulation to minimize air circulation through the low density insulation and combine in a synergistic manner with the low density insulation to increase insulating efficiency.
Another object of this invention is to provide an improvement to existing low density insulation in an insulated attic having a layer of sheetrock or other interior material attached to the bottom of supporting attic ceiling joists, wherein the mass of low density insulation is located between the ceiling joists, supported by the sheetrock, which improvement includes placing high density insulation having a selected thickness and density over the low density insulation to create a layered insulation configuration and minimize the movement of air through the insulation layers to thereby improve the thermal efficiency of the insulation.
A still further object of the invention is to provide an improved insulation configuration for the attics and floors of structures, which insulation configuration includes fiberglass batts or pillows of high density and thickness covering a quantity of low density insulation installed on sheetrock between the ceiling joists of the attic and between floor joists, which batts or pillows serve to isolate the low density insulation and combine with the low density insulation to substantially prevent air from circulating through the combined layers of insulation and increase the efficiency of the insulation configuration, while allowing moisture to move through the insulation layers without collecting therein and damaging the insulation, the underlying sheetrock or any structural members.
Yet another object of the invention is to provide an improved insulation configuration which includes a high density fibrous, loose-fill particulate, or blown insulation placed over a mass of low density insulation to at least partially isolate the low density insulation and create a high density-low density laminate which is characterized by decreased air infiltration and circulation.
Still another object of this invention is to provide a method for increasing the efficiency of insulation in the attics and floors of structures, which method includes the expedient of placing insulation batts or pillows of high density and selected thickness over the low density insulation, in order to isolate the low density insulation and minimize circulation of air through the resulting layers or cells of high and low density insulation.
A still further object of the invention is to provide a method for minimizing the circulation of air and heat through a layered insulation configuration characterized by a low density particulate or batt insulation and a high density insulation cap installed in the attics and floors of structures, which method includes installing high density insulation batts or pillows, or an alternative high density, water vapor-permeable insulation cap or cover, over the low density insulation, in order to substantially isolate the layered insulation combination from air infiltration and circulation.
SUMMARY OF THE INVENTION
These and other objects of the invention are provided in insulation configurations for enhancing the insulating capability of attics and floors, which configurations include particulate or batt insulation of high density positioned over particulate or batt-type, low density insulation, to define layered insulation structures which isolate the low density insulation and minimize air circulation through the resulting insulation configurations. A method for reducing air flow through high and low density insulation laminates located in the attic and beneath the floor of a structure and thereby increasing the efficiency of the insulation, which method includes placing high density, water vapor-permeable particulate insulation or insulation batts or pillows over the low density insulation to substantially isolate the layered insulation configuration from air circulation.
BRIEF DESCRIPTION OF THE DRAWING
The invention will be better understood by referenced to the accompanying drawing, wherein:
FIG. 1 is a perspective view, partially in section, of a structure with the attic area open to inspection and illustrating a preferred mass of low density, particulate insulation capped by a high density insulation batt to define an insulation configuration of this invention;
FIG. 2 is a sectional view taken along line 2--2 of a segment of the layered insulation configuration illustrated in FIG. 1;
FIG. 3 is a sectional view of a layered insulation configuration having a slightly different installation orientation;
FIG. 4 is another layered insulation configuration illustrating the use of loose-fill or particulate insulation of selected high density and thickness to cover underlying low density, particulate insulation;
FIG. 5 is a sectional view of a floor segment illustrating a preferred high density batt-low density particulate insulation configuration of this invention; and
FIG. 6 is a graph plotting temperature versus "R" value for various insulation configurations.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring initially to FIG. 1 of the drawings, a structure 1 is illustrated with walls 11, a window 10 and an attic 6, having a roof 7, carrying roof trusses 8. As illustrated in FIGS. 1 and 2, a preferred insulation configuration for the attic 6 is generally illustrated, with a first layer of blown, particulate, low density insulation 4 located between the ceiling joists 2 and resting on the ceiling material 3 attached to the bottom of the ceiling joists 2. An insulation batt 5 of high density and selected thickness is positioned over the first layer of low density insulation 4 between the ceiling joists 2, to isolate the low density insulation 4 and complete the insulation configuration. The low density insulation 4 is typically applied to the ceiling material 3 and located between the ceiling joists 2 by means of a blowing apparatus, in the case of particulate, loose-fill insulation such as fiberglass and the like. Alternatively, shaped, covered or uncovered low density batts or rolled sheets of non-solid, fibrous insulation may be applied on the ceiling material 3 between the ceiling joists 2, by techniques which are well known to those skilled in the art. As further illustrated in FIG. 1, the ceiling material 3, which is typically "sheetrock" or "gypsum board" material, serves to prevent air encroachment or infiltration into the low density insulation 4 from the bottom, or interior of the structure 1. The insulation mass is isolated on the top by the high density insulation batt 5 to create a layered insulation configuration which effectively limits air infiltration and circulation and reduces heat transfer.
Referring now to FIG. 3 of the drawings, a second insulation configuration is illustrated, wherein high density insulation batts 5 are placed over the ceiling joists 2 and butted end-to-end, thereby further sealing the top of the underlying low density insulation 4. Accordingly, air cannot readily enter or circulate through either the high density insulation batts 5 or the low density insulation 4, due to the presence of the high density insulation batts 5. The efficiency of the resulting layered insulation configuration located between and on the ceiling joists 2 is found to be surprisingly higher than it would normally be under circumstances where only a single thickness of high density insulation 5 or low density insulation 4 is used.
Referring now to FIG. 4, blown, loose-fill or particulate high density insulation 6 replaces the high density insulation batts 5, illustrated in FIGS. 1-3. This blown, loose-fill or particulate high density insulation 6 may be installed according to the knowledge of those skilled in the art.
Referring to FIG. 5 of the drawings, in a third insulation configuration a floor decking 20 is nailed or otherwise mounted to the top edges of parallel, spaced floor joists 10 and high density insulation batts 5 are positioned under a layer of low density insulation 4, which lies adjacent to the floor decking 20 and between the floor joists 10. The high density insulation batts 5 may be stapled or otherwise secured in this position by methods known to those skilled in the art, to define a first layer of insulation.
As detailed in U.S. Pat. No. 4,696,138, to Christopher A. Bullock, a water vapor-permeable film positioned over particulate, low density insulation increases insulation efficiency by minimizing air circulation into the low density insulation. As indicated above, it has surprisingly been found that a high density insulation cap placed over low density particulate insulation creates a layered insulation configuration, using either the high density insulation batts 5 or blown, loose-fill or particulate high density insulation 6, which is particularly effective to achieve this objective. The high density insulation batts 5 and blown, loose-fill or particulate high density insulation 6 illustrated in FIGS. 1 and 4, are not encapsulated in or covered by a moisture vapor-permeable film or cover.
The following insulation configurations numbered 1-6 were tested for thermal insulation efficiency and the pertinent results are compiled in the graph illustrated in FIG. 6. The temperatures plotted on the graph are simulated outside ambient conditions and the temperature at ttle bottom surface of the ceiling material 3 was maintained at 70°, ±0.1° F.
1. A highly instrumented attic structure with no insulation installed over the 1/2 inch gypsum board ceiling.
2. The attic structure described in 1, with approximately ten (10) inches of low density, R 21 blown fiberglass insulation in place over the gypsum board ceiling.
3. The insulated attic described in 2 with a one (1) sheet of DuPont "Tyveck" radiant barrier located over the low density, R 21 blown insulation.
4. The insulated attic described in 2 with one layer of 1.5 mil perforated polyethylene film positioned over the low density, R 21 blown insulation.
5. The insulated attic described in 2 with a one-inch thick, low density fiberglass batt (0.75 lb. per cubic ft. density) encapsulated in the polyethylene film.
6. The insulated attic described in 2 with a one-inch thick high density batt (1.0 lb. per cubic ft. density) placed over the low density, R 21 blown fiberglass insulation.
The tests were conducted in simulated summer and winter conditions and confirmed that the "R" values for the low density, R 21 blown fiberglass insulation were less than one-half of the rated R 21 value in some winter conditions and were significantly lower than the R 21 value for all winter conditions. During summer conditions, the insulation also performed below the expected rated R 21 value. In all cases, when a convection barrier, cap or cover was placed over the low density, R 21 blown insulation, the insulation performance was improved.
The attic structure was initially tested for thermal efficiency with no insulation installed, in order to determine in future tests the true contribution of the various test insulation configurations. It was determined from one winter test at 0.0 degrees F., that the "R" value of the bare gypsum board ceiling was 1.5 and the same was true at 90 degrees F., for a summer test. This is three times higher than the values predicted by current architectural manuals, which list a value of R 0.5 for the gypsum board ceiling.
The next test consisted of blowing low density, R 19 glass fiber insulation into the attic structure by a quaified insulation contractor. It was determined after the installation, by weighing the glass fiber before and after installation and measuring the thickness of the insulation, that the actual "R" value of the low density, R 19 blown insulation was R 21. It was determined that the highly accurate, true, in-place "R" value ranged from R 8.3 at -18 degrees F., to R 12.9 at 20 degrees F., for winter conditions. Summer tests were conducted at 90 degrees F. and 120 degrees F. and ranged from R 9.2 to R 14.1, respectively. These data are plotted on the graph illustrated in FIG. 6.
A radiant barrier was installed over the low density, R 21 blown glass fiber insulation and tested in both simulated winter and summer conditions. The winter test showed an increase in "R" value over the low density, R 21 blown insulation of approximately R 2.5 for all conditions. There were two summer tests conducted at 90 degrees F. and the "R" values were 22.6 and 23.3, respectively. This generally agrees with previous radiant barrier tests which have shown a decrease in heat flux of 40% to 50% when the radiant barriers are placed over low density attic insulation during summer conditions. These data are also plotted in the graph illustrated in FIG. 6.
The radiant barrier was then removed from the attic simulator and was replaced with a single layer of 1.5 mil. perforated polyethylene film. The film configuration consistently performed at approximately R 1 higher than the low density, R 21 blown glass fiber insulation and R 1 lower than the radiant barrier configuration for winter tests. At the summer condition of 90 degrees F., the "R" value was 17.9. These data are plotted in the graph illustrated in FIG. 6.
The single layer of perforated polyethylene film was then removed from the top of the low density, R 21 blown glass fiber insulation and replaced with a one-inch thick, low density glass fiber batt which was encapsulated in the 1.5 mil. perforated polyethylene film. The film was heat-sealed on the edges and open on the ends to define a "pillow". The ends were, however, stapled to partially seal the pillow. The winter tests indicated a significant increase in "R" value, which was expected. The "R" value ranged between R 20 and R 21 when the temperature was in the range from -5 degrees F. and 45 degrees F. The "R" value at -18 degrees F. was 17.1 and the summer condition at 90 degrees F., was 17.9. These data are also plotted in the graph illustrated in FIG. 6.
A one-inch thick high density (1.1 lb./cu. ft.) batt was placed on the low density, R 21 blown glass fiber insulation in place of the low density pillow. It was unexpectedly determined that the "R" value of the resulting insulation configuration was increased by all average of R 2.5 over the one-inch thick low density pillow configuration. The tests were conducted at low temperature only and the "R" values ranged between R 20.2 at -18 degrees F., to R 22.8 at 5 degrees F. These data are also plotted on the graph illustrated in FIG. 6.
The data presented on the graph illustrated in FIG. 6 clearly shows that the one-inch thick high density insulation batt creates a superior insulation configuration when placed over the low density blown insulation and the same could be expected of high density loose-fill, fibrous, blown or particulate insulation.
The term "low density" is used herein to refer to particulate or batt insulation having a density generally in the range of from about 0.40 to about 0.75 pounds per cubic foot, while "high density" refers to insulation having a density above about 0.75 pounds per cubic foot and preferably in the range of from about 0.75 to about 10 pounds per cubic foot. Most preferably, the density of the high density insulation is in the range of from about 0.75 to about 4 pounds per cubic foot.
Test data which were recorded during this research proves by both heat flow measurements and infra-red video photography that air does circulate through low density glass fiber insulation and that at least one of the transport forces for this air circulation is heat-induced natural convection. Data from this research and data from the "Guarded Hot Plate" test for years have indicated that high density glass fiber insulation does conduct more heat than low density glass fiber insulation. Therefore, high density glass fiber insulation has a higher "K" value, or heat transfer coefficient, than low density glass fiber insulation. By definition, this will produce a lower calculated "R" value for high density insulation than for low density insulation.
However, test data which were recorded during this research also proves that a high density glass fiber batt which was one (1) inch thick and had a density of 1.1 lb/cu-ft. reduced air circulation and heat-induced natural convection through the mass of insulation to a level which was not measurable or identifiable during these tests. This was also confirmed by both heat flow measurements and infra-red video photography of the surface of the insulation.
It is apparent from the above data that under circumstances where a high density fiber insulation is placed over low density fiber insulation, the configuration produces a low density, low heat-conducting cavity inside the insulation mass and a high density cap on top of the insulation mass which minimizes air infiltration and circulation into or through the insulation mass. The result is an insulation configuration which is surprisingly superior to either of the single high density or low density configurations.
It is felt that high density insulation alone may be highly effective in reducing air infiltration in, and heat transfer through, the insulation mass. This insulation may be in the form of blown (particulate) insulation or insulation batts or pillows. Furthermore, while high density insulation batts and pillows were used in the test program, it will be understood that high density blown or particulate insulation or any other form of high density insulation is equally well suited for the purpose of this invention.
While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications may be made therein and the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the invention. | Insulation configurations created by low density, loose-fill, particulate, blown insulation and/or fiber batt insulation in combination with high density, loose fill, particulate, blown and/or fiber batt insulation placed under or over the low density insulation, depending upon location. The insulation configurations are designed for, but are not limited to, attic insulation and floor insulation, where low density, loose-fill, particulate, blown and/or fiber batt insulation is normally used. The high density insulation so characterized isolates the low density insulation and greatly reduces air infiltration into, and circulation through, the resulting high and low density insulation configurations. The air infiltration or circulation which the insulation configurations are designed to minimize is generally characterized by, but is not limited to, heat-induced natural convection. A method of installing a high density layer of loose-fill, particulate, blown and/or fiber batt insulation under or over low density, loose-fill, particulate, blown and/or fiber bart insulation, for isolating the low density insulation and creating layered insulation configurations of high efficiency by reducing air infiltration into and through the insulation configurations. | 4 |
[0001] This application claims the priority of Brazilian patent case No. PI0401785-4 filed on Mar. 25, 2004 which is hereby incorporated by reference.
[0002] The present invention relates to a process for preparing a bar toilet soap composed of multiple phases, at least one phase being opaque and at least one phase being translucent. The translucent phase (s) and the opaque phase(s) are mixed during the process, giving rise to a toilet soap wherein one of the phases predominates and the other appears as stripes dispersed in the former.
DESCRIPTION OF THE PRIOR ART
[0003] At present, formulations of bar toilet soaps are known, which are composed of multiple phases, and it is most common to find toilet soaps having only two phases. Various manufacture methods are used for preparing them. Documents of the prior art that disclose formulations of toilet soaps as described above are cited below.
[0004] Some documents disclose toilet soaps having two phases clearly separated from each other, either due to the manufacture process or due to a physical structure separating them, namely:
[0005] Document U.S. Pat. No. 6,555,509 discloses a multiphase toilet article, the phases of which are separated by a membrane, as well as the processes for producing this article. Each phase comprises a different composition. The membrane is at least partly water-soluble, and the material employed to prepare it is selected to dissolve or disintegrate as the product is used. This is a toilet soap that has phases completely separated from each other.
[0006] Document EP 0545716 describes a soap comprising two phases. This soap has a first portion that is at least translucent and may be transparent, and a second portion that is opaque. Each portion of the soap has at least 80% of its mass composed by the same components, and the phases are joined together in the step of molding the toilet soap, preferably having a curvilinear shape. The process for producing this soap is such that a clear composition is arranged in a mold, partly filling it. Later the opaque composition is arranged in the mold, completing its volume. Theses steps of the process may be inverted. Again, it can be concluded that this is a soap that comprises two phases completely separated from each other.
[0007] On the other hand, document U.S. Pat. No. 6,376,441 (corresponding to Brazilian PI 0013372-8) discloses a multiphase molten toilet soap, which has at least one interface that projects along the plane perpendicular to the plane formed by the axles x and y of said toilet soap, and also a process for producing it. The process for producing this toilet soap is continuous, and the cleaning agents comprised within the toilet soap are put into the mold and kept therein until they become hard, being then removed to give way to more molten cleaning agents. The hardened multiphase toilet soap is then ejected from the mold. This mold comprises said interface, which separates the phases until they are completely hardened.
[0008] Document U.S. Pat. No. 6,533,979 discloses a method for producing a soap by using an equipment for molding said soap that comprises two connected tubes, through which two different soap materials of contrasting colors pass and are poured into a mold, resulting in the finished soap. The soap body has stripes from one face to the other in its cross section, that is to say, one phase is injected into the other. There is not mixing between them; the phases are intercalated.
[0009] Documents U.S. Pat. No. 6,413,928 and U.S. Pat. No. 6,440,927 (corresponding to Brazilian documents PI 9813201-6 and PI 9814022-1) deal, respectively, with a multiphase soap and a process for preparing it, which comprise the steps of: a) molding a soap body compressing a granular mixture of detergent, said body having a first surface, said first surface having at least one mold and said mixture comprising at least one detergent active agent; b) preparing a gelatinous mixture under constant stirring and pouring it into the mold, forming a gelatinous portion; and c) hardening and curing the gelatinous portion, which results in a multiphase soap. Again, it is noted that the phases remain separated from each other.
[0010] Document US 2002/0077258 (corresponding to Brazilian document PI 0114018-3) discloses multiphase soaps in which the phases are easily visible when the soap is seen from above or from the sides. Various arrangements of the phases are foreseen, the amount of each of them varying as Well. The phases are arranged in, layers and kept visibly separated from each other.
[0011] Further, document U.S. Pat. No. 6,548,473 (corresponding to Brazilian document PI 9807007-0) discloses a multilayer bar soap comprising a solid compressed body having, at least inside it, a mold and at least one non-compressed and non-encapsulated portion arranged within said mold, and comprising at least one active agent.
[0012] Document U.S. Pat. No. 6,174,845 (corresponding to Brazilian document PI 9808438-0) describes toilet-soap compositions in which an emollient composition is added to the base toilet-soap composition during the extrusion process, which result in a second phase. The second phase, however, is arranged separately from the first one.
[0013] Document U.S. Pat. No. 6,383,999 (corresponding to Brazilian PI 0108259-0) discloses a multiphase toilet soap comprising a plurality of phases of cleaning materials. Preferably, the adjacent phases have different concentrations of components and all the phases have a similar cleaning base. These components are emollients, moisturizing agents, nutrients, anti-aging agents, etc.
[0014] Still other documents describe a process of introducing additives in the bar toilet-soap mass so as to form a dispersed stripes in it, as can be inferred from the documents cited below:
[0015] Document U.S. Pat. No. 6,390,797 (corresponding to Brazilian PI 0000839-7) deals with an apparatus and a process for introducing various additives in solid form to the soap mass in order to produce bar soaps. These soaps have a multicolored and marbled appearance. Soap granulates having a determined color are introduced in the soap body. Further, colored granulates may be introduced by means of a special apparatus that controls the rate of flow of such elements and ensures that they will be directly introduced in a chamber formed by a flight of helical screw.
[0016] Finally, documents U.S. Pat. No. 4,096,221, U.S. Pat. No. 4,094,946, U.S. Pat. No. 4,196,163, U.S. Pat. No. 4,634,654, and U.S. Pat. No. 4,127,372 describe processes and apparatuses for introducing colors in the toilet soaps by using additives, which results in colored stripes.
SUMMARY OF THE INVENTION
[0017] The present invention has the objective of providing a process of preparing multiphase toilet soaps that comprisies the following steps:
[0018] a—adding, in sequence, the following components:
[0019] i—base toilet-soap mass, opacifying agent and chelating agent
[0020] ii—at least one surfactant and emollient
[0021] iii—a chelating agent; and
[0022] iv—essence and anti-oxidizing agent
[0023] to a Mixer ( 1 ) connected, at intervals of at least 10 minutes between the additions of each of the groups (i) to (iv) above;
[0024] b—mixing, during an interval of time sufficient to achieve total homogenization of the components;
[0025] c—introducing the mixture obtained in item b in a roller mill (not shown), according to a lamination velocity until homogenization is achieved;
[0026] d—transferring by conveyor belts, the laminated mass to an Extruder ( 9 ) and extruding it once through the preliminary Trafila ( 8 );
[0027] e—during the preparation of the extruded mass of the opaque phase, adding a translucent phase by means of a conveyor belt or a dosing equipment ( 6 ), with controlled addition time, according to the appearance wished to be achieved;
[0028] f—introducing the mixture containing the opaque and translucent phases in a final Trafila ( 7 ), at a temperature ranging from 60 to 80° C., at a velocity suitable for obtaining a homogeneous and constant product;
[0029] g—introducing the extruded mass ( 5 ) obtained in item f in a cutter (not shown), cutting it in compact form and in the appropriate size compatible with the size of the mold;
[0030] h—molding the extruded and cut mass in a press.
[0031] By using this process, a toilet soap having at least two mixed and well-defined phases (opaque and translucent) is obtained, which do not separate from each other during the use of the toilet soap.
[0032] The present invention has also the objective of providing a multiphase toilet soap prepared according to the process aimed.
BRIEF DESCRIPTION OF THE FIGURES
[0033] The present invention will now be described in greater detail with reference to an embodiment represented in the drawings. The figures show:
[0034] FIG. 1 illustrates the equipment used for preparing the translucent phase to be inserted into the multiphase toilet soap prepared according to the present invention;
[0035] FIG. 2 illustrates the equipment used for preparing the multiphase toilet soap prepared according to the present invention;
[0036] FIG. 3 is a perspective view of the multiphase toilet soap prepared according to the present invention; and
[0037] FIG. 4 is a cross-sectional view of a multiphase toilet soap prepared according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0038] The present invention describes a process for the manufacture/preparation of a bar toilet soap, preferably of vegetable base, composed of at least two phases, one of them being opaque and the other being translucent (the translucent phase is that which permits passage of a certain amount of light), wherein the translucent phase is incorporated into a intermediate step of the process of making the opaque phase, with the use of a dosing belt of device.
[0039] The two types of the phase present in the multiphase toilet soap should be compatible, so that there will be consistency between them. Further, on the one hand the mixture should be stable, maintaining the aspect of each of the phases and, on the other hand, there should be no homogenization of the mixture of the two phases, so that the presence of both phases will be clear.
[0040] The composition of the translucent phase comprises at least base toilet-soap mass, preferably of vegetable base (containing more water-soluble salts of carboxylic acids), translucency promoting agents, a chelating agent, a moisturizing agent, essence, dye. Optionally, emollient and actives may be added.
[0041] On the other hand, the composition of the opaque phase comprises base toilet-soap mass, preferably of vegetable base (containing water-soluble salts of carboxylic acids, an opacifying agent, a chelating agent, an emollient, essence, dye and an anti-oxidizing agent. Optionally, actives may be added.
[0042] In the composition of the multiphase toilet soap of the present invention, the amount of the translucent phase may range from 5.0 to 95.0%, preferably from 10.0 to 20.0% and the amount of opaque phase may range from 5.0 to 95.0%, preferably from 80.0 to 90.0% by weight, based on the total weight of the composition.
[0043] The options of components that are preferably used in the composition of each of the phases are described below. However, other components of each of the classes below, commonly added to the composition of toilet soaps of the prior art, may be added.
Base Toilet-Soap Mass
[0044] Preferably, the toilet-soap base for the composition of the multiphase toilet soap of the present invention is constituted by components of vegetable origin. However, a mass containing components of animal origin, usually found in toilet-soap compositions of the prior art, may be added.
[0045] In the constitution of the base toilet-soap mass, water-soluble salts of carboxylic acids are preferably used. Preferred examples of carboxylic acids the salts of which are ideal for the composition of the base toilet-soap mass are those derived from triglyceride and oils, such as animal tallow, coco-nut oil, babassu oil, oils derived from palm, among other vegetable oils.
[0046] Also, synthetic bases may be used, such as cocoyl, sodium isocyanate and sodium lauryl sarcosinate.
Translucency Promoting Agent
[0047] The translucent phase is that which permits passage of a certain amount of light. This phase will be incorporated into the opaque phase, according to the process of preparing the present invention, in order to compose the multiphase toilet soap.
[0048] In order to obtain a translucent toilet-soap mass, at least one translucency promoting agent is used as, for example, sugars, preferably refined sugar, vegetable and animal stearic acid with trietanolamine, animal or vegetable glycerin, sodium chloride, propyleneglycol and sorbitol.
[0049] Besides adding translucency promoting agents, suitable mixers and/or homogenizers are used so as to bring about the alignment of the molecules due to the mechanical strain, which entails the passage of light.
[0050] In the preferred embodiments of the present invention, refined sugar, vegetable glycerin, vegetable stearic acid with trietanolamine, propyleneglycol, sodium chloride are opted with the function of translucency promoting agents.
Chelating Agent
[0051] The chelating agent exhibits the property of sequestering ions from the solution, that is to say, it is capable of sequestering calcium atoms and magnesium atoms, but preferably exhibits selectivity for binding to ions such as iron, manganese and copper ions. In this sense, its function in the composition of the multiphase toilet soap described herein is to control a possible oxidation action, which might occur and also to provide stability in storage of the cosmetic compositions of the present invention.
[0052] Preferred chelating agents to be added to the composition of the multiphase toilet soap of the present invention are: etidronic acid, citric acid, ethylenediaminetetraacetic acid (EDTA), ethylene diamine phosphonic acid and hydroxyethane diphosphonic acid.
[0053] In the preferred embodiments of the present invention, etidronic acid and tetrasodic EDTA are selected to act as chelating agents.
Moisturizing Agent
[0054] The moisturizing agent in the composition of the multiphase toilet soap promotes the retention of water in the skin of the user, that is to say, it provides water to the skin and also presents the loss of water of the skin. The moisturizing agent further aids in increasing the effectiveness of the emollient, in case this component is present, reduces the staling of the skin and improves the sensitivity of the skin.
[0055] Some examples of moisturizing agents that may be added to the composition of the multiphase toilet soap of the present invention are: glycerol, ethoxylated glycerol, propoxylated glycerol, sorbitol, ethoxylated methylglucose, hydroxypropyl sorbitol, among others, glycerin and vegetable glycerin, and salts of lactate, propyleneglycol, butyleneglycol, polyethyleneglycol, urea, natural oils such as oils and waxes and mixtures thereof.
[0056] In the preferred embodiments of the preparation of the multiphase toilet soap of the present invention, propyleneglycol and vegetable glycerin are used as moisturizing agent.
Essence
[0057] It is optional to add to the composition of the multiphase toilet soap essence selected from a range of possible substances. Essences that are usually added to compositions of toilet soap of the prior art are employed.
[0058] The essence or fragrance may be added both to the opaque phase and to the translucent phase.
Active
[0059] The following actives may be added: lipophilic or hydrophilic components such as seaweed extracts, combination of palmitoil hydroxypropyl triommonium aminopectin, glycerin crospolymer, lecitin and grape-seed oil, bisabolol (anti-inflammatory active), D-pantenol (conditioning active), tocoferol (vitamin E), ascorbic acid (vitamin C).
[0060] Vegetable oils or extracts may be added such as chamomile extract, rosemary extract, thyme extract, calendula extract, carrot extract, common-juniper extract, Surinam cherry extract, guarana extract, cupuaçu butter, carap-nut oil, among others.
[0061] Further, exfoliating microspheres of vegetable exfoliants may be added in order to impart an additional function to the multiphase toilet soap.
[0062] The active components may be added in both the opaque phase and translucent phase.
Anti-oxidizing Agent
[0063] The anti-oxidizing agent acts in protecting the composition of the toilet soap from oxidizing actions.
[0064] Compounds with anti-oxidizing properties that may be added to the variations of composition of the multiphase toilet soap of the present invention are: sulfites, ascorbates, amino acids (for example, glycine, histidine, tyrosine and triptophane), imidiazoles, urocanic acid and derivatives thereof, peptides (for example, D, L-carnosin, D-carnosine and L-carnosin), anserine, carotenoids, carotenes and derivatives thereof (for example, alpha-carotene and beta-carotene), lycopen and derivatives thereof, lipophilic substances such as butyl hydroxytoluene (BHT), butyl hydroxyanisol (BHA), tetradibutyl pentaeritryl hydroxyhydroxinamate, hydrophilic substances such as phenoxyethaneol, benzyl alcohol, methylparaben, propylparaben, hydantoins.
[0065] In the preferred variations of the composition of the multiphase toilet soap of the present invention, butylhydroxytoluene (BHT) is used as an anti-oxidizing agent, especially in the constitution of the opaque phase.
Opacifying Agent
[0066] This component will be added exclusively to the opaque phase of the multiphase toilet soap. Preferred embodiments of opacifying agents to be added to the composition of the multiphase toilet soap of the present invention are titanium dioxide, alumina, zinc oxide, calcium carbonate or mixtures of inorganic minerals. However, other opacifying components usually employed in compositions of toilet soaps of the prior art may be added.
[0067] The opaque phase of the multiphase toilet soap of the present invention comprises an opacifying agent in an amount ranging from 0.1 to 5.0%, preferably from 0.3 to 0.9% by weight, based on the total weight of the composition.
Surfactants
[0068] Preferred embodiments to be used either in isolation or in conjunction in the composition of the multiphase toilet soap as a surfactant, especially in the opaque phase, are alkylglucosides, decyl polyglucose such as decyl polyglucose 2000, sodium cocoil isotianate, sodium lauryl sulphosuccinate.
Dye
[0069] Any dyes found in compositions of toilet soap of the prior art may be used. A few examples of such dyes are: natural carmine, chlorophyll, curcumin, annatto, dyestuffs of vegetable origin, caramel dyestuff and FD&C coloring agents.
[0070] Different kinds of dyestuffs may be used in the same toilet soap, imparting a broader range of colors to the product, especially when the product contains more than one translucent phase.
Emollient
[0071] The function of emollients in compositions intended for skin care is to add or replace lipids and natural oil to the skin.
[0072] Some examples of emollients that may be added to the composition of the multiphase toilet soap are:
conventional lipids such as waxes and other water-soluble components, in addition to polar lipids, mineral oil, natural oils such as esters, silicone oils such as dimethicone copolyol and silicone fluid, soybean lecitin, polyunsaturated fatty acids, lanoline and derivatives thereof such as lanoline and lanoline fatty acids and glycols such as glycerin and propyleneglycol. Some natural oils that may be used are derived from damson seed, sesame seeds, soybean, pea-nut, coconut, olive, cocoa-nut butter, almond, carnauba, cotton seed, rice bran, peach seed, jojoba, macadamia, coffee, grape feed, pumpkin seed, among others and mixtures thereof.
[0074] Some ethers and esters may also be used in the function of emollients, as for example dicaprylic ether, cetyl lactate, isopropyl palmitate, C 12-15 alkyl benzoate, isopropyl myristate, isopropyl isononate and combinations thereof.
[0075] In the preferred embodiments of the present invention, mineral oil and soybean lecitin are used as emollient.
[0076] By using the above-described options, it can be concluded that the constitution of each of the phases may be different, since they may contain different components without impair the final result of the product.
[0077] Other components may also be added in order to impart some further characteristic still not present in the composition of the multiphase toilet soap, for example exfoliant and antimicrobial agents.
Process for Preparing the Multiphase Toilet Soap
[0078] The process of preparing the multiphase toilet soap is, in summary, the mixing of the components of the two opaque and translucent phases, so that the translucent phase will be incorporated into the opaque phase during the extrusion of this second phase, as can be seen in FIGS. 3 and 4 .
[0079] The translucent phase is obtained by using the adequate components, plus application of an intensive and effective mechanical work, preferably by using a Sigma mixer and an extruder, which contributes to achieving the homogenization and stabilization of the Beta crystalline structure. As a result of this sum of factors, a product with translucent appearance is obtained.
[0080] On the other hand, the opaque phase is equivalent to a mass of an ordinary toilet soap in the final extrusion step.
[0081] In the composition of the multiphase toilet soap, the amount of translucent phase may range from 5.0 to 95.0% by weight, preferably from 10.0 to 20.0% and the amount of opaque phase may range from 5.0 to 95.0% by weight, preferably from 80.0 to 90.0%, based on the total weight of the composition.
A. Preparation of the Translucent Phase of the Multiphase Toilet Soap
[0082]
[0000]
TABLE 1
Steps of the Process of Preparing the Translucent Phase
Steps of the process
Components corresponding to each step
1
Base Toilet-Soap Mass
Moisturizing agent(s)
Emollient(s)
Chelating agent(s)
2
Translucency Promoting Agent(s)
Chelating agent
3
Translucency Promoting Agent(s)
4
Translucency Promoting Agent(s)
5
Essence
Dyestuffs
[0083] The process for preparing the translucent phase present in the multiphase toilet soap, illustrated in FIG. 1 , comprises the following steps (the description relates to the preparation of a translucent phase, but there may be more than one translucent phase in the same toilet soap, which will be prepared according to the same process):
[0084] a—adding the components of Step 1 in a Sigma G. Mazzoni Mixer ( 1 ); mixing, for a period of time sufficient for achieving total homogenization among the components of this phase; usually, the time necessary for this homogenization is of about 20 minutes (another mixer that brings about the same homogenization result achieved by using the Sigma G. Mazzoni Mixer may be used);
[0085] b—introducing the mixture obtained in step a— in a Mazzoni Extruder ( 2 ) and extruding it once through the Trafila ( 3 ) and returning to the Mixer ( 1 ) (just as in step a—, other pieces of equipment (extruder, trafila and mixer) that bring the same result achieved by using the above-cited preferred pieces of equipment may be utilized);
[0086] c—adding the components of Step 2 in the Mixer ( 1 ); mixing, for a period of time sufficient to achieve total homogenization of the components of this phase, preferably for about 20 minutes;
[0087] d—introducing the mixture obtained in step c— in a Mazzoni Extruder ( 2 ) and extruding it once through the Trafila ( 3 ) and returning to the Mixer ( 1 );
[0088] e—heating at least one translucency promoting agent of Step 3, other than translucency promoting agent(s) added in step c—, at a temperature of 50° C. and adding this partial composition in the Mixer ( 1 ); mixing for a period of at least 15 minutes;
[0089] f—adding at least one translucency promoting agent of Step 4, other than the translucency promoting agent(s) added in step e—, in the Mixer ( 1 ); mixing this partial composition for about 40 minutes or until total homogenization of the components is achieved and it reaches a translucent appearance;
[0090] g—introducing the mixture obtained in step f— in the Mazzoni Extruder ( 2 ) and, extruding it once through the Trafila ( 3 ) and returning to the Mixer ( 1 );
[0091] h—adding the components of Step 5 in the Mixer ( 1 ); mixing this partial composition for about 15 minutes or until total homogenization of the components of this phase and stabilization of the Beta crystalline structure are achieved;
[0092] i—introducing the mixture obtained in step h— in the Mazzoni Extruder ( 2 );
[0093] j—cutting the bars into pieces (noodles) ( 4 ), preferably ranging from 3.0 to 5.0 cm in length.
[0094] Optionally, actives may be added in Stage 1 of this process step.
[0095] The translucent phase should be removed from the upper part of the extruder in sizes ranging from 0.5 to 15.0 cm, preferably from 3.0 to 5.0 cm in length, and it should be reserved for being added to the multiphase toilet soap during the preparation of the opaque phase.
[0096] The translucent phase may be manufactured 30 days in advance, preferably from 3 to 5 days.
B. Preparation of the Final Multiphase Toilet Soap
[0097]
[0000]
TABLE 2
Steps of the Process and Components of the Opaque Toilet Soap
Components corresponding to each step
Steps of the Process
of the process
1
Base Toilet-Soap Base
Opacifying agent
Chelating agent
2
Surfactants
Emollient
3
Chelating agent
4
Essence
Anti-oxidizing agent
[0098] The process for preparing the multiphase toilet soap, illustrated in FIG. 2 , comprises the following steps:
[0099] a—adding the components of Steps 1, 2, 3 and 4 listed above (opaque phase) in a Sigma G. Mazzoni Mixer (not shown), connected, at intervals of at least about 10 minutes between the additions of each group of components of the steps (another mixer that brings about the same homogenization result achieved by using the Sigma G. Mazzoni Mixer may be used);
[0100] b—mixing, for about 15 minutes or until total homogenization of the components is achieved;
[0101] c—introducing the mixture obtained in step b— in a roller mill (not shown) according to an adequate rolling velocity; the rolling velocity is that usually employed for preparing toilet soaps of the prior art; optionally, the mixture may be introduced in the Mill more than once, until it takes on the form of a homogeneous mass, wherein all the components are dispersed; as a result, a rolled mass with about 0.2 mm in thickness is obtained;
[0102] d—transferring, by means of conveyor belts (not shown), the rolled mass to a Mazzoni Extruder ( 9 ) and extruding it once through the preliminary Trafila ( 8 ) (just as in step a—, other pieces of equipment (extruder and trafila) that bring about the same result obtained by using the above-cited preferred pieces of equipment may be used);
[0103] e—during the preparation of the extruded mass of the opaque phase, the translucent phase is added by using a conveyor belt that acts as a dosing equipment ( 6 ) with controlled addition time, according to the appearance wished to be obtained; optionally, this step may be repeated in order to add more than one translucent phase;
[0104] f—introducing the mixture containing the opaque and translucent phases in the final Trafila ( 7 ), at a temperature ranging from 60 to 80° C., at a velocity adequate for obtaining a homogeneous and constant product;
[0105] g—introducing the extruded mass obtained in item f— in an automatic cutter (not shown), cutting it in compact shape in the adequate size, compatible with the size of the mold;
[0106] h—molding the extruded mass in a press (not shown);
[0107] i—removing the trims that may be present on the molded toilet soap, which can be re-used by means of a continuous process with conveyor belts that transfer the trims to the Mazzoni Extruder ( 9 ).
[0108] The dosing equipment ( 6 ) is preferably constituted by a conveyor belt with controlled velocity, which carries the pieces (noodles) of the translucent phase from the funnel-shaped deposit to the mixing point of the final extruder. The velocity of addition of the translucent phase should be controlled according to the appearance wished to be achieved.
[0109] A preferred embodiment having been described, it should be understood that the scope of the present invention embraces other possible variations, being limited only by the contents of the accompanying claims, which include the possible equivalents.
EXAMPLES OF COMPOSITION OF THE TRANSLUCENT PHASE AND OPAQUE PHASE COMPRISED IN THE MULTIPHASE TOILET SOAP
Example 1
Formulations of the Translucent Phase
[0110] a—adding the base toilet-soap mass, vegetable glycerin, propyleneglycol, etidronic acid, actives in the Sigma G. Mazzoni Mixer ( 1 ); mixing for about 20 minutes until total homogenization is obtained among the components of this step;
[0111] b—introducing the mixture obtained in step a— in the Mazzoni Extruder ( 20 and extruding it through the Trafila ( 3 ) and returning to the Mixer ( 1 );
[0112] c—adding refined sugar, sodium chloride, tetrasodium EDTA in the Mixer 91 ); mixing for about 20 minutes until total homogenization among the components of this step is achieved;
[0113] d—introducing the mixture obtained in step c— in the Mazzoni Extruder ( 2 ) and extruding it once through the Trafila ( 3 ) and returning to the Mixer ( 1 );
[0114] e—heating the vegetable stearic acid up to a temperature of 50° C. and adding this partial composition in the Mixer ( 1 ); mixing for about 15 minutes;
[0115] f—adding trietanolamine in the Mixer ( 1 ); mixing this partial composition for about 40 minutes until total homogenization of the components is achieved and the composition takes on the translucent appearance;
[0116] g—introducing the mixture obtained in step f— in the Mazzoni Extruder ( 2 ) and extruding it once through the Trafila ( 3 ) and returning to the Mixer 91 );
[0117] h—adding essence and dyestuffs in the Mixer ( 1 ). Mixing this partial composition for about 15 minutes until total homogenization of the components of this phase is achieved, as well as the stabilization of the Beta crystalline structure;
[0118] i—introducing the mixture obtained in step h— in the Mazzoni Extruder ( 2 );
[0119] j—cutting the bars into pieces (noodles) ( 4 ) of about 3.0 to 5.0 cm in length.
[0000]
Ingredients
Formula 1 - % weight
Formula 2 - % weight
Base Toilet-Soap Mass
82.00
82.90
Refined Sugar
6.00
5.00
Vegetable Glycerin
4.00
5.00
Essence
1.70
1.70
Trietanolamin
1.60
1.50
Vegetable Stearic Acid
1.50
1.50
Propyleneglycol
1.30
1.00
Sodium Chloride
1.00
0.50
Active
0.50
0.50
Dyestuffs
0.36
0.36
Etidronic Acid
0.02
0.02
Tetrasodium EDTA
0.02
0.02
Example 2
Formulations of the Opaque Phase
[0120] a—adding the base toilet-soap mass, etidronic acid, titanium dioxide, decyl polyglucose 2000, mineral oil, soybean lecitin, active, tetradisodium EDTA, essence and BHT (opaque phase) (in the Sigma G. Mazzoni Mixer turned on) at intervals of 10 minutes between the steps;
[0121] b—mixing for about 15 minutes until total homogenization of the components is achieved;
[0000]
Ingredient
Formula 1 - % weight
Formula 2 - % weight
Base Toilet-Soap Mass
93.80
94.60
Essence
1.70
1.70
Decyl polyglucose 2000
1.50
1.00
Mineral Oil
1.40
1.00
Titanium Dioxide
0.50
0.60
Soybean Lecitin
0.50
0.50
Active
0.50
0.50
BHT
0.05
0.05
Etidronic acid
0.03
0.03
Tetrasodium EDTA
0.02
0.02
[0122] After preparing the above-described phases, the general process of joining the opaque and translucent phases is executed:
[0123] c—introducing the mixture obtained in step b— in the roller Mill according to a conventional rolling velocity;
[0124] d—transferring, on conveyor belts, the rolled mass to the Mazzoni Extruder ( 9 ) and extruding it once through the preliminary Trafila ( 8 );
[0125] e—during the preparation of the extruded mass of the opaque phase, the translucent phase is added by means of a conveyor belt or by means of a dosing equipment ( 6 ), with controlled addition time, according to the appearance which one wishes to achieve;
[0126] f—introducing the mixture containing the opaque and translucent phases in the final Trafila ( 7 ), at a temperature ranging from 60 to 80° C., at a velocity adequate for obtaining a product with homogeneous and constant consistency;
[0127] g—introducing the extruded mass obtained in step f— in the automatic cutter ( 5 ), cutting it in compact form in the adequate size, compatible with the size of the mold;
[0128] h—molding the extruded mass in the press;
[0129] i—removing the trims that may be present on the molded toilet soap, which can be re-used by means of a continuous process with conveyor belts that carry the trims to the Mazzoni Extruder ( 9 ). | The present invention relates to a process of preparing bar toilet soap, composed of multiple phases, at least one of them being an opaque phase and at least one being a translucent phase. The translucent phase and the opaque phase(s) are mixed during the process, wherein the translucent phase is incorporated into the opaque phase during the extrusion of this second phase, giving rise to a toilet soap in which one of the phases predominate and the other appears as stripes dispersed in the first one. | 2 |
FIELD
The present disclosure relates generally to grain dryers, and, in particular, the present disclosure relates to grain dryers configured so that different numbers of ducts in a grain column are selectable for cooling.
BACKGROUND
Duct-type grain dryers (e.g., sometimes called mixed-flow grain dryers) typically do not have any screens that can plug or that may need to be cleaned. This can reduce the need for maintenance and may allow a wide variety of different grains to be dried.
In duct-type grain dryers, grain may flow downward under the influence of gravity, e.g., through a grain column containing a plurality of ducts. The grain may be dried by passing heated air through the grain as the grain flows downward through the grain column. In some duct-type grain dryers, some of the ducts in the grain column might direct the heated air into contact with the downward flowing grain. The heated air may then flow through the downward flowing grain and may be subsequently cooled by the grain. The cooled air may then be directed from the grain column by other ducts in the grain column.
In some applications, after heated drying, the grain might be cooled before the grain exits the grain dryer, e.g., to prevent deterioration during storage. Some duct-type grain dryers, for example, might use pressurized air cooling in their grain columns. For example, ducts might be used to direct the pressurized cooling air into the grain. However, pressurized cooling can result in undesirable heat loss and energy consumption.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for alternatives to existing cooling systems for duct-type grain dryers.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cutaway end view of an example of an interior of a grain dryer.
FIG. 2 is an enlarged view of region 185 in FIG. 1 .
FIG. 3 is a view taken along the lines 3 - 3 in FIG. 2 .
FIG. 4 illustrates cooling air flows and heating air flows in an enlarged view of a portion of the left side of FIG. 1 .
FIG. 5 is a plan view of an example of an adjustable intake assembly as viewed along line 5 - 5 in FIG. 2 .
DETAILED DESCRIPTION
In the following detailed description, reference is made to the accompanying drawings that form a part hereof, and in which is shown, by way of illustration, specific embodiments. In the drawings, like numerals describe substantially similar components throughout the several views. Other embodiments may be utilized and structural and mechanical changes may be made without departing from the scope of the present disclosure. The following detailed description is, therefore, not to be taken in a limiting sense.
FIG. 1 is a cutaway end view of an interior of a duct-type grain dryer 100 . FIG. 2 is an enlarged view of region 185 in FIG. 1 . For some embodiments, grain dryer 100 might not have any screens, e.g., grain dryer 100 might be screenless.
Grain dryer 100 may include a duct (e.g., a plenum) 110 , that may be vertical, between ducts (e.g., grain columns) 115 that might be identical to each other and that might be vertical. Grain (e.g., “wet” grain) to be dried may be received in grain columns 115 from a garner bin 118 . The grain might be gravity fed downward through grain columns 115 into metering sections 120 that may respectively include motor-driven metering rolls 122 , as shown in FIG. 2 . The rotational speed of metering rolls might control the rate at which the grain flows through each of grain columns 115 . For example, the higher the rotational speed of the metering rolls; the higher the rate at which the grain flows through grain columns 115 . Metering sections 120 respectively direct the grain onto conveyers 125 .
It should be recognized the term vertical takes into account variations from “exactly” vertical due to routine manufacturing and/or assembly variations and that one of ordinary skill in the art would know what is meant by the term vertical.
A burner 127 may be located in the interior of grain dryer 100 , below duct 110 and between the respective grain columns 115 . A motor-driven blower (e.g., fan) 130 , such as an axial blower, may be located in the interior of grain dryer 100 , below burner 127 and between the respective grain columns 115 . Operation of blower 130 may cause an inlet 132 (e.g., the suction side) of blower 130 and a region 135 (e.g., that might be referred to as a tub) of grain dryer 100 that is below blower 130 and fluidly coupled to inlet 132 to be at vacuum pressure, e.g., below the atmospheric pressure of the outside air external to grain dryer 100 . Blower 130 directs air through burner 127 that is fluidly coupled to an outlet (e.g., the pressure side) of blower 130 . Burner 127 subsequently heats the air for drying the grain in grain columns 115 .
As used herein “fluidly coupled” means to allow the flow of fluid (e.g., air). For example, air is allowed to flow between fluidly coupled elements, i.e., from one of the fluidly coupled elements to the other. For selectively fluidly coupled elements, air flows from one of the elements to the other in response to an action, such as the opening of a damper between the elements. That is, when one or more dampers are between two elements, the two elements are selectively fluidly coupled to each other, for example. When ducts are fluidly coupled to a region or element, the flow passages within these ducts are fluidly coupled to the region or element, for example.
Each of grain columns 115 might be between duct 110 and a respective duct (e.g., air cavity) 137 that opens to and that is fluidly coupled, through openings 138 , to the outside air (e.g., atmospheric air) that is external to and that surrounds grain dryer 100 . For example, air cavities 137 might be at the pressure of the outside air.
Each air cavity 137 might between a respective heat shield 139 and a respective one of grain columns 115 . That is, the respective heat shield 139 might form at least a portion of an exterior shell of grain dryer 100 , for example. For example, an exterior surface of heat shield 139 might be in contact with the outside air that is external to and that surrounds grain dryer 100 . That is, for example, each heat shield 139 may be between the outside air and a respective air cavity 137 . Heat shields 139 might be made from galvanized steel, for example.
Each of the grain columns 115 includes a plurality of ducts (e.g., channels) 140 and a plurality of ducts (e.g., channels) 142 . For example, each of ducts 140 and 142 may be between duct 110 and an air cavity 137 . Ducts 140 and 142 might alternate along the lengths of grain columns 115 so that a respective duct 142 is at a vertical elevation between the vertical elevations of successively adjacent ducts 140 . That is, for example, respective ones of ducts 142 might be between successively adjacent ducts 140 .
Each of ducts 140 might open into duct 110 . For example, each duct 140 might have an inlet/outlet 144 at one of its ends, such as an end 150 ( FIG. 2 ), that opens into duct 110 , e.g., though a wall 152 of a respective grain column 115 adjacent to duct 110 , as shown in FIG. 2 . An opposite end of that duct 144 , such as an end 154 , might be closed by a portion of a wall 155 of the respective grain column 115 adjacent to a respective air cavity 137 , as shown in FIG. 2 .
For example, ducts 140 might be horizontal and might span the entire distance between walls 152 and 155 of a grain column 115 . Ducts 140 might be transverse (e.g., perpendicular to within routine manufacturing and/or assembly variations) to the direction of the grain flow in grain columns 115 , for example.
It should be recognized that the term horizontal takes into account variations from “exactly” horizontal due to routine manufacturing and/or assembly variations and that one of ordinary skill in the art would know what is meant by the term horizontal. It should be recognized that vertical and horizontal are perpendicular to each other to within routine manufacturing and/or assembly variations.
Each of ducts 142 might open into a respective air cavity 137 . For example, each duct 142 might have inlet/outlet 158 at one of its ends, such as an end 160 ( FIG. 2 ), that opens into a respective air cavity 137 , e.g., though a respective wall 155 , as shown in FIG. 2 . An opposite end of that duct 142 , such as an end 162 , might be closed by a portion of a respective wall 152 , as shown in FIG. 2 .
For example, ducts 142 might be horizontal and might span the entire distance between walls 152 and 155 of a grain column 115 . Ducts 142 might be transverse (e.g., perpendicular) to the direction of the grain flow in grain columns 115 , for example.
A lower portion of duct 110 might include an outer duct (e.g., channel) 175 on either side of an inner duct (e.g., channel) 180 , as shown in FIGS. 1 and 2 . For example, a wall 182 of a pair of walls 182 might be between a respective one of outer ducts 175 and inner duct 180 . Burner 127 might be located within inner duct 180 between walls 182 , as shown in FIGS. 1 and 2 . Inner duct 180 is configured to receive pressurized air exiting the pressure side (e.g., the outlet) of blower 130 . Outer ducts 175 and inner duct 180 might be vertical, for example.
Each of a plurality of dampers 190 , such as dampers 190 1 to 190 4 ( FIG. 2 ), might be configured to selectively partition each of outer ducts 175 into two regions, e.g., a region above a respective damper and a region below the respective damper. Each of dampers 190 1 to 190 4 might be configured to be selectively opened and closed. For example, each of dampers 190 1 to 190 4 might be configured to be selectively moved from an open position, e.g., as shown for each of dampers 190 1 to 190 3 in FIG. 2 , to a closed position, e.g., as shown for damper 190 4 in FIG. 2 . In its closed position, damper 190 4 extends across a respective duct 175 from a respective wall 182 to respective wall 152 . Each of dampers 190 1 to 190 4 may be configured to be selectively pivoted, e.g., about a shaft 192 , between its open and closed positions.
When a damper 190 is closed, that damper 190 partitions (e.g., divides) a respective duct 175 , and thus an adjacent grain column 115 , into a region above the closed damper 190 and a region below the closed damper 190 . For example, each of closed dampers 190 4 partitions its respective duct 175 into a region 195 above that closed damper 190 4 and a region 197 below that closed damper 190 4 , e.g., by closing region 195 off from region 197 , as shown in FIG. 2 . That is, for example, a region in a respective grain column 115 above a closed damper 190 4 might correspond to the region 195 in an adjacent duct 175 , and a region in the respective grain column 115 below that closed damper 190 4 might correspond to the region 197 in the adjacent duct 175 .
The region in a grain column 115 above a closed damper 190 , such as closed damper 190 4 , might be subjected to heating, where heating air might flow from the region in the adjacent duct 175 above the closed damper 190 , such as region 195 above closed damper 190 4 , into the region in that grain column 115 above the closed damper 190 through the inlet/outlets 144 of ducts 140 that open into the adjacent duct 175 . The air may then flow from region in the grain column 115 above the closed damper 190 into the adjacent air cavity 137 through inlet/outlets 158 .
The region in a grain column 115 below a closed damper 190 , such as closed damper 190 4 , might be subjected to cooling, where cooling air might flow from the adjacent air cavity 137 into the region in that grain column 115 below the closed damper 190 through the inlet/outlets 158 of ducts 142 that open into that air cavity 137 . The air may then flow from region in the grain column 115 below the closed damper 190 into the region in the adjacent duct 175 below the closed damper 190 , such as region 197 below closed damper 190 4 , through inlet/outlets 144 . For example, a closed damper 190 might select region in a grain column 115 above the closed damper 190 for heating and a region in that grain column 115 below the closed damper 190 for cooling.
A portion of a grain column 115 might have a plurality zones adjacent to a duct 175 that are defined by the locations of dampers 190 . For example, zone 200 1 , zone 200 2 , and zone 200 3 of a grain column 115 might respectively be between successively adjacent dampers 190 1 and 190 2 , successively adjacent dampers 190 2 and 190 3 , and successively adjacent dampers 190 3 and 190 4 . A zone 200 4 might be between damper 190 4 and a lowermost end (e.g., an outlet) 201 of a duct 175 . A lowermost zone 202 of a grain column 115 might be below the outlet 201 of a duct 175 .
When all of dampers 190 1 to 190 4 adjacent to a respective grain column 115 are open, all of the zones 200 of the respective grain column 115 might be subjected to heating, while the lowermost zone 202 is subjected to cooling. For example, lowermost zone 202 might always be subjected to cooling, regardless of the state (e.g., open or closed) of any of dampers 190 1 to 190 4 .
Note that the number of the zones 200 of each grain column 115 , and thus the length of each grain column 115 subjected to cooling, may be selectively adjustable using the dampers 190 . For example, selectively closing dampers 190 4 and leaving the remaining dampers 190 1 to 190 3 selects zones 204 4 below closed dampers 190 4 for cooling and the remaining zones 200 1 to 200 3 above closed dampers 190 4 for heating. For example, selectively closing dampers 190 3 and leaving the remaining dampers 190 1 , 190 2 , and 190 4 open selects zones 200 3 to 200 4 below closed dampers 190 3 for cooling and the remaining zones 200 1 and 200 2 above closed dampers 190 2 for heating. For example, different ones of the plurality of dampers 190 are configured to respectively select different amounts (e.g., a different number of zones 200 ) of the grain columns for cooling.
FIG. 3 is a view taken along the lines 3 - 3 in FIG. 2 , showing the general layout of ducts 140 and 142 in a portion of a representative zone 200 and/or a representative zone 202 . Note, for example, that each of ducts 140 might have an inlet/outlet (e.g. an opening) 310 along its bottom. For example, each duct 140 might be an open channel that faces downward toward the bottom of a respective grain column 115 . An inlet/outlet 310 , for example, might span the entire length of a respective duct 140 , e.g., from wall 152 to wall 155 of a respective grain column 115 .
Each of ducts 142 , for example, might have an inlet/outlet (e.g. an opening) 320 along its bottom. For example, each duct 142 might be an open channel that faces downward toward the bottom of a respective grain column 115 . An inlet/outlet 320 , for example, might span the entire length of a respective duct 142 , e.g., from wall 152 to wall 155 of a respective grain column 115 .
FIG. 4 illustrates cooling air flows and heating air flows in an enlarged view of a portion of the left side of FIG. 1 , including the left side of FIG. 2 . Arrows 405 , 410 , 415 , 420 , 425 , 430 , 435 , 440 , and 441 represent flows of cooling air, and arrows 450 , 455 , 460 , 465 , 470 , 471 , 472 , 473 , and 474 represent flows of heating air.
In FIG. 4 , a portion 480 of a respective grain column 115 is selected for cooling in that it is below closed damper 190 3 . For example, closing damper 190 3 selects portion 480 for cooling. For example, portion 480 might include the zones 200 3 and 200 4 shown in FIG. 2 . Note that zone 200 4 below closed damper 190 4 is selected for cooling in FIG. 2 . Therefore, FIGS. 2 and 4 illustrate how closing different dampers (damper 190 4 in FIG. 2 and damper 190 3 in FIG. 4 ) respectively selects different portions (e.g., different lengths) of a grain column 115 for cooling, and thus different numbers of ducts 140 and different numbers of ducts 142 for handing cooling air for cooling the grain. For example, a larger number of ducts 140 and ducts 142 are used for handing cooling air in FIG. 4 when damper 190 3 is closed than in FIG. 2 when damper 190 2 is closed. Note that each of the grain columns 115 and the respective ducts 175 adjacent to grain columns 115 may be as described below in conjunction with FIGS. 3 and 4 .
Portion 485 is subjected to heating in FIG. 4 in that it is above closed damper closed damper 190 3 . For example, portion 485 might include the zones 200 1 and 200 2 shown in FIG. 2 . Note that zones 200 1 to 200 3 above closed damper 190 4 are subjected to heating in FIG. 2 . Therefore, FIGS. 2 and 4 illustrate how closing different dampers (damper 190 4 in FIG. 2 and damper 190 3 in FIG. 4 ) causes different portions (e.g., different lengths) of a grain column 115 to be subjected to heating. For example, the dampers 190 1 to 190 4 may be respectively configured to selectively close each of the respective the respective ducts 175 at different locations along a length of the respective ducts 175 .
In portion 480 of the grain column 115 below closed damper 190 3 in FIG. 4 , the closed damper 190 3 might cause cooling air to flow into a duct 142 from a respective air cavity 137 , as shown by arrows 410 , through the inlet/outlet 158 of that duct 142 that opens into the air cavity 137 and then to flow into grain column 115 from that duct 140 , as shown by arrows 415 , through the inlet/outlet 320 ( FIG. 3 ) of that duct 142 . The closed damper 190 3 might cause the cooling air to then flow into a duct 140 from grain column 115 , as shown by arrows 420 , through the inlet/outlet 310 ( FIG. 3 ) of that duct 140 and then to flow from that duct 140 , as shown by arrows 405 , into the region 486 of duct 175 (e.g., corresponding to the portion 480 of grain column 115 ) below the closed damper 190 3 through the inlet/outlet 144 of that duct 142 that opens into region 486 of duct 175 below the closed damper 190 3 . The cooling air flowing in the region 486 of duct 175 may then flow from region 486 , as shown by arrows 440 , into the region 135 that is below blower 130 and fluidly coupled to inlet 132 of blower 130 .
Grain in the grain column 115 may transfer heat to the cooling air so that the cooling air flowing in a duct 175 is heated. Note that the region 486 of duct 175 might be fluidly coupled to the inlet 132 , e.g., to the suction side, of blower 130 , and the region 486 of duct 175 might be at a lower pressure than air cavity 137 while blower 130 is operating. That is, blower 130 might cause the region 486 of duct 175 to be at vacuum pressure, for example.
During cooling of a zone 202 in FIG. 4 , the cooling air may flow into a duct 142 from air cavity 137 , as shown by an arrow 441 , through the inlet/outlet 158 of that duct 142 and may then flow into grain column 115 from that duct 142 , as shown by arrows 430 , through the inlet/outlet 320 ( FIG. 3 ) of that duct 142 . The cooling air may then flow into a duct 140 from the respective grain column 115 , as shown by arrows 425 , through the inlet/outlet 310 ( FIG. 3 ) of that duct 140 and may then flow from that duct 140 into the region 135 , as shown by arrow 435 , through the inlet/outlet 144 of that duct 140 .
Note that the grain in the grain column 115 transfers heat to the cooling air so that the cooling air flowing into region 135 from zone 202 is heated. Also note that zone 202 might be subjected to cooling during the operation of blower 130 , and thus grain dryer 100 , regardless of whether any of the dampers 190 are open or closed. For example, zone 202 might receive cooling air whenever blower 130 is operating.
In FIG. 4 , heating air might flow into a region 488 of duct 175 , as shown by arrows 470 , above closed damper 190 3 , e.g., from the upper portion of duct 110 ( FIG. 1 ). Note that region 488 of duct 175 corresponds to the portion 485 of grain column 115 above closed damper 190 3 . Closed damper 190 3 might cause the heating air flowing in region 488 of duct 175 to flow into a duct 140 from region 488 , as shown by arrows 450 , through the inlet/outlet 144 of that duct 140 and then to flow into grain column 115 from that duct 140 , as shown by arrows 455 , through the inlet/outlet 310 ( FIG. 3 ) of that duct 140 . Closed damper 190 3 might then cause the heating air to flow into a duct 142 from grain column 115 , as shown by arrows 460 , through the inlet/outlet 320 ( FIG. 3 ) of that duct 142 and then to flow from that duct 142 into air cavity 137 , as shown by arrows 465 , through the inlet/outlet 158 of that duct 142 .
Note that the region 488 of duct 175 might be fluidly coupled to the outlet, e.g., to the pressure side, of blower 130 , and the region 488 of duct 175 might be at a higher pressure than air cavity 137 , and thus region 486 of duct 175 , while blower 130 is operating.
During heating of the upper portion of a grain column 115 above duct 175 , and thus above the zones 200 in FIG. 2 and above portion 485 in FIG. 4 , heating air may flow into a duct 140 , as shown by an arrow 471 in FIG. 4 , from the upper portion of duct 110 through the inlet/outlet 144 of that duct 140 and may then flow into grain column 115 from that duct 140 , as shown by arrows 472 , through the inlet/outlet 310 ( FIG. 3 ) of that duct 140 . The heating air may then flow into a duct 142 , as shown by arrows 473 , from grain column 115 through the inlet/outlet 320 ( FIG. 3 ) of that duct 142 and may then flow from that duct 142 into air cavity 137 , as shown by arrow 474 , through the inlet/outlet 158 of that duct 142 .
Note that the portion of a grain column 115 above ducts 175 may be heated regardless of the configuration of dampers 190 . For example, the portion of a grain column 115 above ducts 175 is heated whenever grain dryer 100 is operation (e.g., blower 130 and burner 137 are in operation), regardless of whether dampers 190 are open or closed. Also note that the heating of portion 485 above the closed damper 190 3 , the cooling of portion 480 below the closed damper 190 3 , the cooling of zone 202 , and the heating of the portion of a grain column 115 above ducts 175 may occur concurrently while grain dryer 100 is operating.
An adjustable intake assembly 210 might be located below the lowermost ends of grain columns 115 , upstream of inlet 132 of blower 130 . Adjustable intake assembly 210 might be fluidly coupled to the suction side of blower 130 , for example. Adjustable intake assembly 210 might be configured to adjust the amount of outside air that is drawn into grain dryer 100 from the atmosphere external to grain dryer 100 . For example, adjustable intake assembly 210 might be configured to adjust the amount of outside air that enters region 135 . During operation of grain dryer 100 , blower 130 draws the adjusted amount of outside air into region 135 .
The outside air might be cooler than the cooling air from the grain columns 115 that enters region 135 from ducts 175 and/or zone 202 . The cooling air from grain columns 115 might mix with the outside air within region 135 . As such, the mixed air might be warmer than the outside air. Blower 130 then causes the warmer mixed air to flow through burner 127 .
The warmer mixed air acts to reduce the heating load on burner 127 , thereby reducing the fuel consumption of burner 127 by about 15 to 20 percent and reducing the combined fuel and power consumption by about 30 to 40 percent, e.g., compared to pressurized cooling systems used in conventional duct-type grain dyers that do not recycle cooling air to preheat outside air before the outside air reaches the burner. The warmer mixed air is lighter (e.g., has a lower density) than the outside air. This can reduce the load on, and thus the power consumption of, blower 130 , e.g., compared to pressurized cooling systems used in conventional duct-type grain dyers that do not recycle cooling air to preheat outside air before the outside air reaches the blower.
As such, adjustable intake assembly 210 might be configured to adjust the amount of outside air that is mixed with the cooling air from the grain columns 115 that is heated by the grain. For example, adjustable intake assembly 210 may be configured to adjust the amount outside air that enters region 135 through adjustable intake assembly 210 from zero percent of the cooling air that is heated by the grain, in which case adjustable intake assembly 210 does not allow any outside air to enter region 135 directly from adjustable intake assembly 210 , to about 15 to 25 percent of the cooling air that is heated by the grain.
FIG. 5 is a plan view of an example of an adjustable intake assembly 210 as viewed along line 5 - 5 in FIG. 2 . In the example of FIG. 5 , adjustable intake assembly 210 might include a selectively adjustable door (e.g., that might be referred to as an adjustable outside-air blend door) 510 that might be configured to selectively adjust a size of an inlet 520 to the region 135 of grain dryer 100 that is under blower 130 and between grain columns 115 .
For example, door 510 might be configured to selectively move (e.g., slide) over an opening 530 so as to selectively uncover a portion of opening 530 that is inlet 520 and to cover a remaining portion 540 of opening 530 , as shown in FIG. 5 . That is, for example, selectively sliding door 510 to different locations adjusts the size of inlet 520 . For example, door 510 might be configured to selectively uncover different portions of opening 530 , where the different uncovered portions of the opening 530 may respectively allow different amounts of outside air to be drawn therethrough into region 135 .
When door 510 is completely closed, door 510 covers the entire opening 530 , and little or no outside air is drawn directly into region 135 through adjustable intake assembly 210 . Door 510 might be configured to adjust the amount of opening 530 , that is inlet 520 , that is uncovered by door 510 from zero percent of the size of opening 530 when door 510 covers the entire opening 530 to 100 percent of the size of opening 530 when the entire opening 530 is uncovered by door 510 . When the entire opening 530 is uncovered by door 510 , the amount outside air that enters region 135 through adjustable intake assembly 210 might be about 85 percent of the cooling air that gets heated by the grain.
Grain dryer 100 might include a scalper drag 198 , as shown in FIG. 1 . For example, scalper drag 198 might be configured to separate large foreign materials (e.g., larger than the size of the grains) from the grain before the grain enters garner bin 118 and subsequently enters grain columns 115 from garner bin 118 . In one example, scalper drag 198 might include a conveyer that might drag the grain across a screen that allows the grain to pass through its mesh, but not any materials larger than the mesh, and thus the size of the grains. For example, the conveyer might include a plurality of scrapers coupled to a chain that might move in a continuous loop for moving (e.g., dragging) the scrapers over the screen. The scrapers might drag the grain and any larger materials over the screen, where the grain passes through the screen while the scrapers drag the larger materials that do not pass through the screen off the screen.
CONCLUSION
Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement that is calculated to achieve the same purpose may be substituted for the specific embodiments shown. Many adaptations of the embodiments will be apparent to those of ordinary skill in the art. Accordingly, this application is intended to cover any adaptations or variations of the embodiments. | A grain dryer has a grain column configured to receive grain to be dried and ducts extending from a first wall of the grain column to a second wall of the grain column. The grain dryer is configured so that different numbers of the ducts are selectable for handling cooling air used for cooling the grain. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation application of U.S. Ser. No. 07/710,860, filed Jun. 6, 1991 now U.S. Pat. No. 5,374,414, which is itself a continuation-in-part of United States Patent application, entitled DIAMOND-REINFORCED MATRIX COMPOSITES, to Natishan et al., filed May 10, 1991, U.S. Ser. No. 07/698,218 now abandoned and incorporates herein by reference the entirety of both predecessor applications.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the production and use of filaments and use of diamond-coated or diamond filaments, such as fibers, tubes and whiskers.
2. Description of the Prior Art
Small diameter tubes are utilized in many areas of both commerce and research. They are found in biomedical applications as probes and medicinal dispensers, as filtration media in chemical and purification processes, and in such esoteric areas as chaff media for jamming RF frequencies. As described in the parent, copending United States Patent application, entitled DIAMOND-REINFORCED MATRIX COMPOSITES, to Natishan et al., filed May 10, 1991, U.S. Ser. No. 07,698,218, the entirety of which is incorporated herein by reference, diamond and diamond-coated filaments, including diamond and diamond-coated fibers, tubes and whiskers are also useful as reinforcement materials for composites, including, but not limited to thermal management materials. In all of these areas, research continues in an effort to develop tubules or fibers with enhanced properties (increased hardness, lower chemical reactivity, increased thermal conductivity, etc.).
Diamond is inert in a variety of environments including inorganic acids, bases and organic solvents, including solutions such as hot aqua-regia (2/3 HCl and 1/3 HNO 3 ), hot aqua-fortis (2/3 H 2 SO 4 and 1/3 HNO 3 ) and hot caustic solutions (KOH). Additionally, diamond has a very high thermal conductivity (a factor of 5 greater than copper), it is an electrical insulator which can be doped to become a semi-conductor, it has an excellent resistance to wear, and it has a frictional co-efficient similar to that of Teflon™. These materials properties provide many opportunities for use in the areas described above.
SUMMARY OF THE INVENTION
Accordingly, it is an object of this invention to make diamond and diamond-coated filaments.
It is another object of the present invention to make diamond and diamond-coated filaments with useful thermal, electrical and mechanical properties.
It is a further object of the present invention to make diamond and diamond-coated filaments by a process which permits great variation of the ratio of core to diamond diameter.
It is yet another object of the present invention to make diamond tubules.
These and additional objects of the invention are accomplished by coating filamentous substrates with diamond by a chemical vapor deposition process. If desired, the substrate may then be etched or dissolved to convert the diamond-coated filament into a diamond filament.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Generally, diamond or diamond-coated filaments made according to this invention are tubes (hollow), fibers or whiskers having a substantially greater length than diameter, and having a cross-sectional thickness of about 5 to about 200 μm, and typically about 100 μm to about 200 μm. The terms "filament" and "fiber", "tube" and "whisker", as used herein, are intended to encompass, in addition to forms having the traditional round cross-section, forms having other than the traditional round cross-section, such as star-shaped, square, hexagonal, octagonal, etc. In this specification and the claims that follow, the term "filament" is generic and encompasses tubes, fibers, and whiskers; the terms "fiber" and "whisker" refer to non-hollow (i.e., solid) structures; and the term "tube" refers to a hollow structure which may have the dimensional characteristics of either fibers or whiskers. Fibers are short in two dimensions and essentially continuous in one dimension. Whiskers are short in two dimensions, and of relatively small length. The diamond coating on the fibers is in the form of a sheath which completely or partially encompasses the substrate, or, if it lacks a substrate, is self-supporting.
Diamond tubes have been created using a hot filament assisted chemical vapor deposition (FACVD) method. Due to the way in which the tubes are produced, there is no inherent reason why the tubes cannot be made such that the wall thickness can be varied from a very small fraction of the total diameter to a fraction approaching unity which will essentially produce a fiber.
The diamond or diamond-coated filaments of this invention are made by depositing diamond on an appropriate filamentous substrate by chemical vapor deposition and then optionally removing the substrate. Chemical vapor deposition is typically performed according to the process described by Morrish et al. in U.S. Ser. No 07/516,585, filed Apr. 30, 1990, the entirety of which is incorporated herein by reference. For example, the surface of substrate filaments may be scratched with diamond and coated with oil prior to depositing diamond thereon by fiber assisted chemical vapor deposition (FACVD). While preferable for high nucleation, scratching and oil-coating of substrate filaments are not absolutely required for the process according to the present invention. If the substrate filaments are to be prepared for deposition by scratching, scratching may be done by any method. One possible method scratches the substrate filaments by placing them in an ultrasonic cleaner containing diamond grit.
The filamentous substrate upon which the diamond is grown may be any material, such as Cu, W, SiC, quartz, graphitic carbon and Cu-coated graphite, suitable as a substrate for FACVD deposition of diamond thereon, which can be fabricated as a filament. Materials suitable as substrates for the FACVD deposition of diamond typically can withstand a predominantly hydrogen atmosphere at ˜600-1000° C., preferably ˜800-1000° C., for a sufficient time to permit diamond nucleation and growth thereon. If diamond tubes or completely diamond filaments are to be made, the substrate filament should be of a material which may be easily removed without damaging the diamond deposited thereon. For example, copper provides an excellent substrate for the preparation of diamond tubes, since, after diamond deposition, the copper may be dissolved in a strong acid.
In principle diamond filaments can be produced by this method on any diameter filament. The major constraint on the wire is that its radius of curvature should be such that sufficient diamond particles can fit around it to form a tube. The crystal size of the diamond particles can be controlled to sub-micron levels. Within these constraints, diamond tubes can be formed which will range from those where the wall thickness is a very small fraction of the diameter and the void is large, to those where the void is a very small fraction of the diameter and the tube essentially becomes a fiber. Tubes have been produced to date where the walls are very small fractions of the total diameter: wall thickness=2-5 μm, void ˜130 μm and length of up to one inch.
Diamond filaments can also be produced by growing on a graphite fiber and then etching the graphite away. The graphite, which normally would be immediately etched away by the atomic hydrogen, is passivated by a passivating material, for example a metal such as copper, long enough for diamonds to nucleate on the surface of the graphite fiber. It is possible to grow filaments and tubes of arbitrary length by controlling the degree to which the tube is allowed to form before etching the graphite core away. Further growth will then thicken and/or fill in the partial tubes or fibers. By this method, a completely diamond, non-hollow (i.e., solid) filament may be produced.
If desired, the diamond-coated or diamond filament may be doped by including a dopant, such as B 2 O 3 , P 2 O 5 , etc., in the feed gas. The amount of dopant incorporated into the diamond will depend upon the concentration of dopant in the feed gas.
Having described the invention, the following examples are given to illustrate specific applications of the invention including the best mode now known to perform the invention. These specific examples are not intended to limit the scope of the invention described in this application. For example, other methods of diamond deposition by chemical vapor deposition, such as the use of an RF plasma torch, may be used in conjunction with the present invention.
EXAMPLES
Example 1
Production of Diamond Tube by FACVD of Diamond on Copper Followed by Chemical Etching
Diamond tubes were produced in a filament assisted chemical vapor deposition, FACVD, reactor by passing hydrogen and methane gases over a hot filament. The diamond tubes were grown on wires that were placed in the deposition system. This discussion will concentrate on tubes grown on copper wires but any material which could withstand a predominantly hydrogen atmosphere at ˜600-1000° C., typically between ˜800 and 1000° C., for a sufficient time to permit diamond nucleation and growth thereon, would be suitable. Copper wires were scratched by placing them in an ultrasonic cleaner with a slurry of 0.1 mm diamond particles for ˜15 minutes. The wires were then coated with a hydrocarbon oil (hydrocarbon vacuum pump oil, specifically HE-175 Leybold vacuum pump oil), using a cotton swab dipped in oil and applying sufficient oil to saturate the wire surfaces, to enhance growth. The wires were placed in the deposition chamber and the diamond was grown under the following conditions: Pressure=40 torr, filament temperature=2100-2200° C., substrate temperature=850±50° C., gas flow=100 SCCM H 2 /1.01 SCCM CH 4 and deposition time of approximately 4 hours. The result was series of copper wires coated with diamond. The copper was then chemically removed using a solution of concentrated nitric acid which left the diamond sheath (tube) undamaged.
Scanning electron microscopy showed that the tubule had an inner diameter of approximately 100 μm and a wall thickness of approximately 2 μm. The length of this tubule was approximately 3 cm. The tubule was formed by first depositing diamond onto a 100 μm diameter copper wire whose surface was properly prepared, followed by dissolving the copper wire in concentrated nitric acid. The micrographs illustrate the following observations: The cross-section of the fiber was uniformly circular, conforming to the original shape of the copper wire. The wall thickness is uniform around the circumference and down the length of the tubule--the gap in the tubule is breakage due to excessive tweezer force.
Micrographs taken of the tubule surfaces normal to the tubule long axis showed the uniformity of diameter along the length of the tubule. These micrographs also showed that the outer surface of the tubule, although somewhat rougher than the inside face of the tubule, is still fairly uniform. The inner surface of the tubule, as evidenced by the micrographs, was extremely smooth and uniform. These micrographs also demonstrated the tubules were free of pores and holes and are uniform.
Example 2
Growth of Diamond on Graphite Filaments Overcoated with Copper
Deposition of diamond was carried out as described above for the copper samples, except that no chemical etch was employed. Micrographs of diamond tubules formed by depositing diamond on copper-coated graphite fibers while simultaneously etching the graphite away were taken. In this process, as the diamond is deposited on the properly prepared surfaces of the copper-coated graphite, the hydrogen simultaneously etches the graphite away, leaving a tubule of diamond with an inner copper coating, which copper coating is also quickly etched away by further active hydrogen, leaving simply a tubule of diamond. These micrographs showed that the coatings were uniform and continuous, indicating that the diamond has successfully deposited onto the entire surface. In micrographs of incompletely coated fibers, the hollow core was observable through gaps along the length of the fibers.
The advantage of diamond tubule growth via the two-step copper wire technique for growing tubules is the increase in uniformity and lack of pores. The advantage of the diamond tubule formed by deposition onto copper-coated graphite is that the tubule is formed in one step, i.e. by simultaneous deposition and etching.
Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. | Filamentous substrates are coated with diamond by a chemical vapor deposition process. The substrate may then be etched away to form a diamond filament, such as a diamond tube or a diamond fiber. In a preferred embodiment, the substrate is copper-coated graphite. The copper initially passivates the graphite, permitting diamond nucleation thereon. As deposition continues, the copper-coated graphite is etched away by the active hydrogen used in the deposition process. As a result a substrate-less diamond fiber is formed. Diamond-coated and diamond filaments are useful as reinforcement materials for composites, is filtration media in chemical and purification processes, in biomedical applications as probes and medicinal dispensers, and in such esoteric areas as chaff media for jamming RF frequencies. | 3 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority from Great Britain Application Serial Nos. 0423463.9, 0423470.4, 0423474.6, 0423483.7, and 0423517.2, all filed Oct. 22, 2004.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to an amphibious vehicle and, in particular, to a vehicle which can function as an all-terrain vehicle “ATV” (sometimes called “a quadbike”) on land and as personal watercraft “PWC” (sometimes called a “jetski” or a “wave runner”) on water.
[0003] Known PWCs are all consistent in dimension and typically have a beam of 1.15 m-1.23 m, a length of 2.93 m-3.34 m and a planing hull with a maximum dead rise angle of less than 9°.
[0004] Known ATVs are also consistent in dimension and have a maximum track width of 1220 mm (and typically have a track width of around 1150 mm) and a maximum length of 2085 mm (and typically a length of around 1850 mm).
[0005] In the past the creators of amphibious vehicles have either adapted existing PWC designs to provide limited land mode capability or have adapted existing ATV designs to provide limited marine capabilities. For instance, in U.S. Pat. No. 5,690,046 of GRZECH a PWC design is adapted with the resulting vehicle have the same dimensions as a PWC, in particular the track width of the vehicle is kept within the beam of the hull and the dead rise of the hull is conventional.
SUMMARY OF THE INVENTION
[0006] The present invention provides in a first aspect an amphibious vehicle comprising:
[0007] a sit-astride seat;
[0008] a planing hull;
[0009] at least four wheels, all of which are movable between a lowered ground-engaging land mode location and a raised water mode location, two of the four wheels being front steerable wheels which are, at least in the land mode of vehicle, connected to handlebars which can be operated by the driver to steer the vehicle;
[0010] an engine which in the land mode of the vehicle is connected to at least one of the wheels to drive the wheel; and
[0011] marine propulsion means to propel the vehicle in water; wherein the hull has a beam of at least 1250 mm.
[0012] The unique beam of the vehicle, larger than for a conventional PWC gives a vehicle with sufficient displacement to give adequate freeboard on water while also allowing sufficient ground clearance for land use off-road.
[0013] The present invention provides in a second aspect an amphibious vehicle comprising:
[0014] a sit-astride seat;
[0015] a planing hull
[0016] at least four wheels, all of which are movable between a lowered ground-engaging land mode location and a raised water mode location, two of the four wheels being front steerable wheels which are, at least in the land mode of vehicle, connected to handlebars which can be operated by the driver to steer the vehicle;
[0017] an engine which in the land mode of the vehicle is connected to at least one of the wheels to drive the wheel; and
[0018] marine propulsion means to propel the vehicle in water; wherein
[0019] the front steerable wheels are spaced apart by an outer track of at least 50 mm greater than a beam of the hull.
[0020] The applicant has adopted an approach of having four wheels, mounted on suspension arms which place them at a track width outside the beam of the hull when in land mode; this gives good land mode operation including off-road land mode operation. Since the suspension arms extend through the hull the effective planing area of the hull is reduced and so the beam must be chosen with a certain minimum. The track width of the vehicle is then at a width much greater than that conventionally chosen for ATVs. The vehicle of the present invention is uniquely dimensioned and this provides a vehicle which is both capable on land and on water.
[0021] The present invention provides in a third aspect an amphibious vehicle comprising:
[0022] a sit-astride seat;
[0023] a planing hull;
[0024] at least four wheels, all of which are movable between a lowered ground-engaging land mode location and a raised water mode location, two of the four wheels being front steerable wheels which are, at least in the land mode of vehicle, connected to handlebars which can be operated by the driver to steer the vehicle;
[0025] an engine which in the land mode of the vehicle is connected to at least one of the wheels to drive the wheel; and
[0026] marine propulsion means to propel the vehicle in water; wherein
[0027] a planing surface of the planing hull has a dead rise angle of above 10°.
[0028] The vehicle has a planing surface with a dead rise angle unusually high for a planing PWC; this keeps the vehicle manoeuvrable despite a wide beam.
[0029] The present invention provides in a fourth aspect an amphibious vehicle comprising:
[0030] a sit-astride seat;
[0031] a planing hull;
[0032] at least four wheels, all of which are movable between a lowered ground-engaging land mode location and a raised water mode location, two of the four wheels being front steerable wheels which are, at least in the land mode of vehicle, connected to handlebars which can be operated by the driver to steer the vehicle;
[0033] an engine which in the land mode of the vehicle is connected to at least one of the wheels to drive the wheel; and
[0034] marine propulsion means to propel the vehicle in water; wherein
[0035] the vehicle has a length L and the handlebars are located between 0.5L and 0.63L along the vehicle length as measured from the transom to the bow.
[0036] The handlebars are far nearer the stern/rear of the vehicle than is normal in a PWC or a ATV. This gives good handling on water and land for a vehicle somewhat heavier than a usual PWC or ATV.
[0037] The handlebars of the ATV are typically located near the very front of the vehicle. The handlebars of a PWC are typically located two thirds of the way along the vehicle (measured from the stern). The applicant has realised that for manoeuvrability both on land and water the handlebars are best placed about half way along the vehicle (as measured from the transom). The enclosed volume in front of the vehicle gives buoyancy to the vehicle on water and also allows for the front wheels to be at least partly enclosed when retracted (which helps the aerodynamics of the vehicle) and further allows for a vehicle cooling system to have a forwardly located radiator, i.e. an air/water heat exchanger; such a radiator is not needed by a PWC and the radiator located in front of the engine in an ATV (this being a position exposed to air flow in an ATV).
[0038] These and other features and advantages of the present invention will become apparent from the following detailed description of preferred embodiments which, taken in conjunction with the accompanying drawings, illustrate by way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] FIG. 1 is a perspective view from above of an amphibious vehicle according to the present invention;
[0040] FIG. 2 is a perspective view from below of the vehicle of FIG. 1 ;
[0041] FIG. 3 is a plan view from above of the vehicle of FIGS. 1 and 2 ;
[0042] FIG. 4 is a plan view from below of the vehicle of FIGS. 1 to 3 ;
[0043] FIG. 5 is a side elevation view of the vehicle of FIGS. 1 to 4 ;
[0044] FIG. 6 is a front elevation view of the vehicle of FIGS. 1 to 5 ;
[0045] FIG. 7 is a rear elevation view of the vehicle of FIGS. 1 to 6 ;
[0046] FIG. 8 is the same perspective view as FIG. 1 , but with the vehicle's wheels in raised positions; and
[0047] FIG. 9 is the same perspective view as FIG. 2 , but with the vehicle's wheels in raised positions.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0048] FIG. 1 shows an amphibious vehicle 10 having a body formed from a deck panel 11 and a hull 12 which are joined at a join line 13 . The vehicle has four wheels 14 , 15 , 16 , 17 which are each rotatable for wheel retraction about an axis running longitudinally fore and aft along the vehicle 10 . A retraction mechanism can rotate the suspension arms 18 , 19 , 20 , 21 to thereby rotate the wheels 14 , 15 , 16 , 17 to retracted positions (see FIGS. 8,9 ) for marine use.
[0049] The vehicle has a bow 22 and a stern 23 . A jet drive 24 powers the vehicle on water, an inter 25 being provided in the hull 12 . The rear wheels 15 , 16 of the vehicle are driven.
[0050] The wheels 14 , 15 , 15 , 17 are in land mode operation positioned at least in part outside the beam of the hull 12 (see FIGS. 3 and 4 ). The beam B is 1400 mm (this being the maximum beam of the vehicle) while the outer track width T 1 of the front wheels (measured from one tyre's outer extremity to the other tyre's outer extremity) is 1500 mm and the outer track width T 2 of the rear wheels is 1600 mm. The track width T 2 is greater than the track width T 1 ; the front wheels are connected to their wheel hubs in a different orientation to the rear wheels to achieve at least part of this difference. The track width T 1 and T 2 give good stability in land use. The track width T 1 is smaller to allow for easier steering of the front wheels and a tighter turning circle.
[0051] The vehicle has an overall length of 3050 mm. A length of from about 2400 mm to about 3050 mm has been found to be most advantageous for amphibious applications as such length provides for adequate planing area for waterborne operation without being overly large for use on land.
[0052] The vehicle has an overall length L 1 of 3050 mm as measured from the transom and a relatively short wheelbase WB of 1380 mm, and optionally up to about 1500 mm. This corresponds to a ratio of the wheelbase to the overall length of between about 48% and 53%. While such ratio sacrifices approach and departure angles, improvement gained in terms of breakover angle and hydrodynamic bow shape have been found to most advantageous for amphibious applications.
[0053] The beam choice is important for several reasons. First, the vehicle should have a reasonable amount of freeboard when afloat. The vehicle is heavier than a PWC and so would sit deeper in the water if of the same beam. On land the vehicle needs a certain ground clearance which dictates that the draft should not be increased. Hence ensuring that the beam is above 1250 mm ensures that sufficient displacement is achieved whilst achieving adequate freeboard and whilst achieving adequate ground clearance. Secondly, the need for rotating suspension arms means that the hull surface is not uninterrupted; instead apertures must be provided through which the suspension arms rotate. Covers 30 , 31 , 32 , 33 rotatable with the suspension arms are provided which at least in part cover the aperture when the wheels are retracted. However the planing area of the hull is nevertheless somewhat reduced and the beam must be adequate to provide for sufficient planing area that the vehicle can rise on the plane easily.
[0054] The unusually wide beam of the vehicle dictates against the use of a shallow dead rise angle for the planing area of the vehicle. In PWCs the dead rise angles of the planing surfaces are typically below 9°. In contrast the dead rise angle α of the vehicle is consistently 20.7° along the centre line (see FIG. 7 ) in a planing surface of the vehicle. This resists the vehicle planing transversely when cornering on water, which would be a problem due to wide beam otherwise. Angles above 15° are preferred.
[0055] The overall length L 1 of the vehicle is 3050 mm, whilst the length L 2 to of the handlebars (measured from the transom) is 1634 mm; thus the handlebars are located 0.55 along the length of the vehicle. In PWCs usually the handlebars are at least 0.6L along their length and in ATVs the handlebars are usually at least 0.66L along their length. The positioning of the handlebars is unusual so as to position the driver in a location on the vehicle which meets the requirements of manoeuvrability on land and on water while also positioning the driver in a location to give good weight distribution to assist the vehicle getting on to the plane on water. Furthermore the bow part of the vehicle in front of the handlebars gives extra displacement to ensure good freeboard and allow the positioning of a radiator (an air/water heat exchanger) in front of the handlebars in a good position for airflow. The part of the vehicle body in front of the handlebars also allows the front wheels to be partly enclosed when retracted and this assists the aerodynamics of the vehicle.
[0056] The minimum ground clearance of the vehicle on land (see FIG. 6 ) is 220 mm.
[0057] The present invention proposes a vehicle with a unique set of dimensions. This stems from designing a vehicle for good capabilities both on land and water, rather than adapting existing PWC and ATV designs.
[0058] While a particular form of the present invention has been illustrated and described, it will also be apparent to those skilled in the art that various modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is not intended that the invention be limited except by the appended claims. | A planing amphibious vehicle with retractable wheels and a sit-astride seat having dimensions that impart enhanced capability in both land as well as water modes of operation. The beam, track, dead rise angle and the location of the handlebars cooperate to enhance freeboard and ground clearance without sacrificing manoeuvrability. The length is at least 2400 mm; the beam is at least 1250 mm; the deadrise angle at least 10°; and the handlebars are located only slightly forward of the halfway distance from transom to bow. | 1 |
TECHNICAL FIELD
[0001] This document relates generally to methods for determining the ambient air humidity of a vehicle, for preventing window misting and for determining whether an evaporator of a vehicle air-conditioning system is damp or dry, and corresponding devices for completing these methods.
BACKGROUND
[0002] In motor vehicles, knowledge of the relative humidity in the ambient air is necessary or useful, in particular for regulating the ventilation or air-conditioning system such that the relative humidity in the passenger compartment is as comfortable as possible without the vehicle windows misting up from the outside or inside.
[0003] Normally, the ambient air humidity is measured by means of dedicated moisture sensors. Thus DE 10 2009 019 128 A1 discloses determining, by means of moisture sensors, the absolute or relative humidity of the air before and after it flows through the evaporator of a vehicle air-conditioning system, in order to take any necessary measures for drying the evaporator and hence preventing misting of the windows.
[0004] Relative humidity sensors, including psychrometers used to measure the relative air humidity, are however relatively costly, provide rather imprecise measurement values and are not always reliable.
[0005] The current method is based on the object of simplifying the control and regulation of vehicle air-conditioning systems, in particular to be able to determine the relative humidity in the ambient air of the vehicle with as little cost as possible, to be able to prevent window misting in a simple manner, and also to be able to determine easily whether or not the evaporator is damp.
SUMMARY
[0006] This object is achieved according to the invention with the methods and devices as set forth herein.
[0007] The method according to the invention for determining the ambient air humidity is based on the knowledge that, in vehicles with air-conditioning systems, it is possible to conclude the relative humidity from the temperature behavior of the evaporator outlet air after switching off the compressor when the evaporator is damp and while the air-conditioning system is in fan mode, and from the temperature of the ambient air, because there is a clear and reproducible correlation between said temperature measurement values and the actual ambient air humidity as long as the evaporator is damp.
[0008] Therefore only very simple and reliable temperature sensors are required to determine the relative humidity of the ambient air.
[0009] It is advantageous to obtain the measurement values of the ambient air temperature and air outlet temperature of the evaporator while the vehicle is moving forward at a speed typical of road traffic. In this case, it is guaranteed that the fresh air for the air-conditioning system is at the temperature of the ambient air at its inflow point. It has been found that, on its path to the evaporator through any ducts, the fresh air absorbs a defined heat quantity which results from the drive motor and other vehicle ancillaries such as e.g. the air delivery fan, so that the temperature of the fresh air has risen by a defined value—which is also constant if the air delivery quantity remains the same—when it enters the evaporator. This temperature rise is a vehicle-specific value which is typically around 3K, e.g. between 2K and 4K.
[0010] When the air-conditioning system is switched on and the compressor is then switched off while the evaporator is damp, i.e. condensation water has been deposited on the heat exchange surface exposed to the aspirated ambient air, after around one minute all refrigerant in the evaporator of the air-conditioning system will have evaporated. After this one minute, the evaporator is then only cooled by the condensation water still evaporating in the air flow through the evaporator, and hence assumes an approximately constant temperature which depends on the humidity of the ambient air. Only when all condensation water in the evaporator has evaporated—which is typically the case after around 10 minutes—does its temperature rise again, namely to the ambient air temperature plus the abovementioned temperature increase from heat absorption in the vehicle front region.
[0011] The greater cooling of the evaporating water film in the evaporator, whose temperature essentially assumes the temperature of the air exiting the evaporator, compared with the temperature of the air entering the evaporator which is known to be the ambient air temperature plus the temperature increase from heat absorption, thus constitutes a measure of the relative humidity of the ambient air. This method of measuring the relative humidity is similar to measurement by means of psychrometers, and the relative humidity can easily be read from a reference table in the same manner as for psychrometer measurements, or be determined using a suitable function or similar.
[0012] The air outlet temperature from the evaporator is usually measured as early as possible e.g. after around one or two minutes after switching off the compressor.
[0013] The knowledge that the temperature of the fresh air on its path to the evaporator rises during travel by a predefined value, also forms the basis for a method according to the invention for preventing window misting in a vehicle with an air-conditioning system. When the compressor of the air-conditioning system was switched on and has then been switched off, while the air-conditioning system remains in fan mode, it is determined whether the evaporator is damp by monitoring the air outlet temperature from an evaporator of the air-conditioning system, and if it is damp, a currently set dewpoint temperature threshold value for compressor activation is reduced.
[0014] Both said methods are based on the knowledge of whether or not the evaporator is damp. It is known from DE 197 28 577 A1 to obtain this knowledge by comparison of the evaporator temperature with the dewpoint temperature of the fresh air, but a dedicated dewpoint sensor or a temperature and humidity sensor pair is required for this.
[0015] The knowledge that the temperature of the fresh air on its path to the evaporator rises by a predefined value during driving, forms the basis of a particularly simple method for determining whether an evaporator of a vehicle air-conditioning system is damp or dry, in that the state of the evaporator is simply regarded as damp if the air outlet temperature of the evaporator, around one or two minutes after switching off the compressor while the air-conditioning system remains in fan mode, lies closer to a measured ambient air temperature than the sum of the measured ambient air temperature and a vehicle-specific temperature rise value, and otherwise is simply regarded as dry. This method is admittedly relatively rough but is sufficient for the purposes described herein and possibly further purposes.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0016] FIG. 1 is an example of the temporal development of the evaporator air outlet temperature after switching off a vehicle air-conditioning system.
[0017] FIG. 2 is a sketch illustration to demonstrate the determination of the evaporator state.
[0018] FIG. 3 is a sketch illustration to demonstrate the determination of the ambient air humidity.
DETAILED DESCRIPTION
[0019] In a wind tunnel, a travel of a motor vehicle with internal combustion engine and air-conditioning system was simulated at a speed of 50 kph, wherein the air flowing through the wind tunnel had a temperature of 14° C. and a relative humidity of 60%. A temperature sensor was provided in the air outlet from the evaporator of the air-conditioning system, to measure the air outlet temperature from the evaporator.
[0020] The simulated travel was continued with the air-conditioning system running until a stationary state was reached in which the air outlet temperature from the evaporator had assumed a constant value of around 3 to 4° C. Under said conditions, the evaporator is damp and the condensation water quantity deposited on the heat exchange surface of the evaporator is substantially constant since surplus water drips off.
[0021] At a certain time—in FIG. 1 at experiment time 67 minutes—the compressor of the air-conditioning system was deactivated and within a period of around one minute, all refrigerant present in the evaporator of the air-conditioning system had evaporated. This phase is marked in FIG. 1 with a vertically elongated, dotted rectangle.
[0022] After this around one minute, the evaporator is then cooled only by the evaporating condensation water and assumes an approximately constant temperature. The condensation water here evaporates with a substantially constant drying rate (i.e. quantity per time unit), wherein the air outlet temperature of the evaporator rises only slightly. This phase is indicated in FIG. 1 with a horizontally elongated, dotted rectangle. The air outlet temperature of the evaporator rises only slightly and does not remain fully constant because the evaporator surface dries unevenly.
[0023] The level of the air outlet temperature from the evaporator, which is set during this phase of substantially constant water evaporation, is determined by the temperature, speed and humidity of the air flowing over the evaporator surface. Its temperature is the sum of the ambient air temperature and a vehicle-specific temperature rise value from heat absorption from the vehicle, which in this vehicle is 3K, i.e. for this test drive 17° C. Also the speed of the air flowing over the evaporator surface under said conditions is constant or is held as constant as possible.
[0024] Thus the resulting air outlet temperature of the evaporator in practice depends only on the relative humidity of the ambient air, and therefore knowledge of the air inlet temperature of the evaporator—which is the ambient air temperature plus a constant temperature rise of here 3K—and measurement of the air outlet temperature of the evaporator at a time around one or a few minutes from switching off the compressor while the evaporator is damp, allows conclusion of the relative ambient air humidity. The drier the air flowing into the evaporator, the lower the resulting temperature level of the evaporator outlet air; therefore the greater cooling of the evaporating water film in the evaporator is a measure of the relative humidity of the air flowing through the evaporator.
[0025] When all the condensation water in the evaporator has evaporated, which in the test example was the case after 15 minutes, the air outlet temperature of the evaporator rises again and finally, when the evaporator is completely dry, reaches the 17° C. of the air intake temperature.
[0026] Naturally, it is only possible to draw a conclusion about the relative ambient humidity from the ambient air temperature and air outlet temperature of the evaporator if the evaporator is damp when the compressor is switched off.
[0027] A particularly simple method of determining the evaporator state as damp or dry when the compressor of the air-conditioning system is switched off but in fan mode, so fresh air still flows through the air-conditioning system, while the vehicle is in motion, is now described with reference to FIG. 2 . This method is admittedly relatively rough but adequate for the present purposes.
[0028] According to FIG. 2 , half the temperature rise value (1.5 K) is deducted from the air inlet temperature of the evaporator—which is equal to the air outlet temperature when the evaporator is fully dry (in the above example 17° C.). It should be appreciated that the air outlet temperature is the ambient air temperature (14° C.) plus 3K temperature increase from heat absorption—in order to define a threshold temperature (15.5° C.). If the air outlet temperature from the evaporator, around one minute after switching off the air-conditioning system, lies below the threshold temperature, the state of the evaporator can be regarded as damp, whereas if it lies above this temperature, it is dry.
[0029] With reference to FIG. 3 , an example is now explained for how the relative ambient humidity can be determined in concrete terms, wherein the measurement curves shown in FIG. 3 were determined under the conditions given above (travel speed 50 kph, ambient air temperature 14° C., evaporator air intake temperature 17° C., compressor switched off after around 1 minute, fresh air fan set to 3/7), wherein however the ambient air humidity varied.
[0030] FIG. 3 shows the air outlet temperature of the evaporator as a thick line and the relative humidity of the ambient air as a thinner line, each depending on the relative humidity of the evaporator inlet air, wherein both lines are evenly rising functions.
[0031] For example, if the level of the air outlet temperature of the evaporator which results during the phase marked with the horizontally elongated, dotted rectangle in FIG. 1 , is 12° C., we move from the point on the thick line corresponding to 12° C. vertically upward along arrow P to the thinner line, and on the left-hand scale read the relative humidity of the ambient air belonging to this intersection point, around 73%.
[0032] Similarly, for the example of FIG. 1 , the ambient air humidity is 60%.
[0033] The example of FIG. 3 , in which the measurement curves were obtained in relation to the relative humidity of the evaporator inlet air, serves merely for illustration. We see that it is not necessary to know the relative humidity of the evaporator inlet air, and also it is not necessary to carry out the method described here as illustration in order to determine the ambient air humidity.
[0034] Rather in practice, an empirically obtained reference table is stored in the air-conditioning system control unit or computing device, which gives the relative humidity of the ambient air belonging to a given ambient air temperature and a given air outlet temperature from the evaporator, in the same way as a table of relative humidity as a function of temperatures at the dry and damp thermometer is used with a psychrometer.
[0035] The method described with reference to FIG. 2 for determining whether the evaporator state is damp or dry, also allows a particularly simple method for preventing window misting from condensing moisture from the evaporator when the compressor of the air-conditioning system was in operation but has been switched off while the vehicle is still in motion. This method, like that above, also requires the air-conditioning system to be operating in fan mode and also not in defrost mode.
[0036] If by monitoring the air outlet temperature from the evaporator, it is determined in this way that the evaporator is damp, a corresponding marker “evaporator damp” is set.
[0037] If the marker “evaporator damp” is set, the current dewpoint temperature threshold value for compressor activation is reduced.
[0038] The air outlet temperature continues to be monitored, and if the evaporator is detected as dry, the marker “evaporator damp” is deleted.
[0039] If the vehicle is parked and later re-started, it is checked whether the marker “evaporator damp” is set, and if so, the air-conditioning system is automatically switched on immediately and operated so that the windows do not mist up at all.
[0040] The foregoing has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the embodiments to the precise form disclosed. Obvious modifications and variations are possible in light of the above teachings. All such modifications and variations are within the scope of the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled. | A method for determining relative humidity in ambient air of a motor vehicle with an air-conditioning system is provided. That method includes determining, from measurement values of ambient air temperature and the air outlet temperature of an evaporator of the air-conditioning system, the ambient air humidity. Further, that method includes measuring the air outlet temperature of the evaporator at a time at which the compressor of the air-conditioning system was switched on and then has been switched off while the air-conditioning system remains in fan mode, and also after waiting until the evaporator contains no further liquid refrigerant of the air-conditioning system but is still damp. | 1 |
TECHNICAL FIELD
[0001] The present invention relates to a new retargeted virus, to corresponding permissive propagation cells and to a new system for the propagation of native tropism-ablated adenoviral vectors by using a different ligand/pseudo-receptor pair, allowing retargeting of said vectors.
BACKGROUND OF THE INVENTION
[0002] Adenoviruses (Ad) are able to infect a variety of cell types, but their wide tropism is a limitation for certain applications such as cancer therapy, because both the normal and diseased cells are transduced. The unspecific transduction has not only the negative effect on normal cell function, but also decreases the amount of therapeutic viruses delivered to the diseased cells. Therefore, targeted vectors have been developed in order to selectively localize gene expression to the tissue of interest.
[0003] Uptake of the Ad vectors (AdV) derived from serotypes 2 and 5 is a two-stage process, which involves an initial interaction of the viral fiber protein with cellular receptors such as CAR (coxsackievirus and Ad receptor) (Bergelson J M, et al., Science, 275(5304): 1320-1323,1997; and Defer C, B. M., et al., J Virol., 64(8): 3661-3673,1990). The CAR binding domain is localized on the knob region of fiber (Santis G, et al., J Gen Virol, 80: 1519-1527, 1999). Ad binding is then followed by the internalization of the virus, which is mediated by the interaction of the RGD motif of the penton base (viral protein) with secondary cellular receptors identified as αv integrins. This step allows virus internalization via receptor-mediated endocytosis (Wickham T J, et al., Cell, 73(2): 309-319, 1993). Based on the virus entry mechanisms, several strategies were developed to create new CAR-independent entry pathway for the re-targeting of AdVs.
[0004] Several studies were undertaken using either chimeric fibers or exchanging fibers from different serotypes as a simple way to alter AdV tropism (Shayakhmetov D M, et al., J Virol, 74(6): 2567-2583, 2000) since it was suggested that they might recognize different receptors and consequently have different tropism. However, true targeting of AdVs requires the ablation of the vector interaction with their natural receptors, as well as the redirection of the vector to another type of receptor, which is specific to the target cells.. Mutagenesis of the fiber has been done to ablate virus-CAR interaction in vitro. Substitutions within knob region of fiber dramatically reduce the transduction of various CAR-positive cell lines (Alemany R and C. D T., Gene Ther, 8(17): 1347-1353, 2001; Jakubczak J L, et al., J virol, 75(6): 2972-2981, 2001; Roelvink P W, et al., Science, 286(5444): 1568-1571, 1999; and Leissner P, et al., Gene Ther, 8(1): 49-57, 2001). The shaft domain of the fiber has also been changed to modify Ad natural tropism. It was shown that the high transduction efficiency of the liver and the spleen was dramatically reduced by the replacement of a shorter shaft within the fiber (Nakamura T, et al., J Virol, 77(4): 2512-2521, 2003). On the other hand, in order to redirect AdVs to target cells, viral capsid proteins (fiber, penton base, and hexon) were genetically modified by insertion of new ligands or chemically combined with ligands of specific receptors. Ligands such as poly-lysine, RGD motif, NGR peptides, epithelium growth factor (EGF) and gastrin releasing peptide (GRP), respectively targeting heparan sulfates, integrins, aminopeptidase N (CD13), EGF and GRP receptors, have been evaluated for their capacity to alter viral tropism (Wickham T J, et al., Cell, 73(2): 309-319, 1993; Krasnykh V, et al., J Virol, 72(3): 1844-1852, 1998; Vanderkwaak T J, et al., Gynecol Oncol, 74(2): 227-234, 1999; Dmitriev I, et al., J Virol, 74(15): 6875-6884, 2000; and Hong S S, et al., Virology, 262(1): 163-177, 1999). Recently, a synthetic 33-amino-acid immunoglobulin G (IgG)-binding domain derived from staphylococcal protein A was inserted into the Ad fiber making possible a directed gene transfer to a wide variety of cell types by simply changing the target-specific antibody (Volpers C, et al., J Virol, 77(3): 2093-2104, 2003).
[0005] As a result of the ablation of binding to its native receptors, AdV can no longer be produced in the current complementing cell lines; hence the need for new packaging cells. One approach is to construct cell lines expressing an alternate pseudoreceptor, which allows the binding and uptake of targeted vectors. Thus, in addition to the targeting ligand incorporated into the AdV capsid for cell-specific transduction, another pseudoreceptor-binding ligand should also be inserted in the vector for their entry and propagation in packaging cells. This pair of de novo designed pseudoreceptor-ligand would be completely artificial, such that no natural receptors could be used for entry of the vector through the new ligand in vivo. For example, a cell line expressing the pseudoreceptor made of a membrane-anchored single-chain antibody against hemagglutinin (HA) was shown to be able to support HA-tagged AdV production (Einfeld D A, et al., J Virol, 73(11): 9130-9136, 1999). Another cell line expressing the pseudoreceptor, which contains an anti-His sFv, allowed the infection of AdV carrying histidine-incorporated fiber (Douglas J T, et al., Nat Biotechnol, 17(5): 470-475,1999).
[0006] The overall strategy for the development of Ad vectors (AdV) for the delivery of transgenes in specific tissues relies both on the ablation of Ad native tropism and the introduction of new tropism for target cells. In the process, AdVs ablated for their natural receptor interactions would be unable to grow in current cell lines. Consequently such ablated AdVs require new packaging cells for their generation.
[0007] It would be highly desirable to be provided with a new modified virus ablated of its native tropism, which could be used as a “universal virus” that could be retargeted to specific targets.
SUMMARY OF THE INVENTION
[0008] One aim of the present invention is to provide a new modified virus ablated of its native tropism, which could be used as a “universal virus” that could be retargeted to specific targets.
[0009] Another aim of the present invention is to provide a new modified virus ablated of its native tropism, which cannot replicate in most naturally-occurring cells.
[0010] It is thus an object of the invention to establish a new modified virus ablated of its native tropism and so modified as to be propagation or replication incompetent in most cells.
[0011] Another aim of the present invention is to provide new cells that have been modified to be infection permissive and to allow replication of the virus of the present invention.
[0012] In accordance with the present invention there is provided a modified virus ablated of its natural receptors interactions with an unmodified or non-naturally occurring cell, said modified virus comprising a non-native polypeptide, said modified virus having an altered tropism conferred by said non-native peptide, and replicating only in cells that can interact with said non-native peptide, said virus being incapable of infecting a cell through a CAR-dependent entry pathway.
[0013] The modified virus can be made from or derived from, for example a virus selected from the group consisting of adenovirus, retrovirus, lentivirus, adeno-associated virus, Reoviridae, Picornaviridae, Parvoviridae, Papovaviridae and Caliciviridae, more preferably from human adenovirus such as human adenovirus serotype 2 or 5.
[0014] In one embodiment of the invention, the non-native polypeptide replaces, is incorporated into, or forms a fusion protein with, a viral protein component (such as an adenoviral fiber protein) of the wild type virus.
[0015] In one embodiment of the invention, the non-native polypeptide is incorporated into an adenoviral fiber protein such that the wild-type fiber knob or cell binding domain thereof is removed.
[0016] In one embodiment of the invention, the non-native polypeptide is or comprises a combinatorial protein or an affibody.
[0017] In one embodiment of the invention, the non-native polypeptide comprises one or more sequence from a bacterial receptor ligand.
[0018] In one embodiment of the invention, the non-native polypeptide comprises at least one repeat of a sequence as set forth in SEQ ID NO:1.
[0019] In another embodiment of the invention, the non-native polypeptide comprises at least one repeat of a sequence as set forth in SEQ ID NO:2.
[0020] In one embodiment of the invention, the non-native polypeptide binds a non-naturally occurring production cell or permissive cell.
[0021] In one embodiment of the invention, the modified virus further comprises a retargeting adapter comprising i) a binding moiety for binding the non-native polypeptide and ii) a further binding moiety of a receptor for retargeting said virus on cells expressing said receptor.
[0022] In a further embodiment of the invention, the non-native polypeptide comprises at least one repeat of a sequence as set forth in SEQ ID NO:1 and said binding moiety for binding the non-native polypeptide comprises at least one repeat of SEQ ID NO:2.
[0023] In another embodiment of the invention, the non-native polypeptide comprises at least one repeat of a sequence as set forth in SEQ ID NO:2 and said binding moiety for binding the non-native polypeptide comprises at least one repeat of SEQ ID NO:1.
[0024] The adapter in one embodiment binds to the non-native polypeptide through non-covalent physical forces selected from the group consisting of van der waals forces, electrostatic forces, stacking interactions, hydrogen bonding and steric fit.
[0025] The non-native polypeptide may optionally comprise a cleavage site positioned in a location that enables a further binding moiety of a receptor to be added on the modified virus for retargeting said virus on cells expressing said receptor.
[0026] The binding moiety is preferably capable of binding to a cell specific ligand.
[0027] In one embodiment of the invention, the modified virus further comprises a site for insertion of one or more desired therapeutic genes or nucleic acid molecules.
[0028] In accordance with the present invention, there is provided a cell containing a modified virus as defined above.
[0029] Still in accordance with the present invention, there is provided a permissive cell for a modified virus as defined above, which is capable of being cultured to propagate said modified virus.
[0030] Further in accordance with the present invention, there is still provided a non-naturally occurring permissive cell expressing a surface receptor recognizing or binding a non-native polypeptide as defined above.
[0031] In accordance with the present invention, there is also provided a non-naturally occurring permissive cell expressing a surface receptor recognizing or binding a non-native polypeptide as defined above, wherein said surface receptor comprises at least one copy of the amino acid sequence as set forth in SEQ ID NO:2 or SEQ ID NO:1, as the case may be, depending on the other element of the binding pair.
[0032] In accordance with the present invention, there is also provided a method for producing a modified virus as defined above in cell culture, comprising the steps of: i) genetically modifying a virus to produce a modified virus ablated of its natural receptors interactions with an unmodified or non-naturally occurring cell, said modified virus comprising a non-native polypeptide, said modified virus having an altered tropism conferred by said non-native peptide, and replicating only in cells that can interact with said non-native peptide; ii) infecting permissive cells with said modified virus; and iii) culturing said cells to produce the virus. The method may further comprise a step of iv) harvesting the modified virus produced. The method may additionally comprise a step of v) purifying the modified virus produced.
[0033] The modified virus of the present invention can be use in therapy.
[0034] In accordance with the present invention there is also provided the use of the modified virus as defined above in the preparation of a medicament for the treatment of tumor cells or proliferating cells.
[0035] Still in accordance with the present invention, there is further provided a pharmaceutical composition comprising a modified virus as defined above and a pharmaceutically acceptable carrier or excipient.
[0036] There is also provided in accordance with the present invention a reagent kit comprising a modified virus and a cell, both as defined herein.
[0037] In accordance with the present invention, there is also provided a medicament or a precursor thereof comprising a virus as defined herein.
[0038] Still in accordance with the present invention, there is also provided the use of a virus as defined herein for the preparation of a medicament or a precursor thereof for treating or preventing genetic diseases, tumor diseases, autoimmune diseases or infectious diseases.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] FIG. 1 is a schematic diagram of the EGFR-Ecoil pseudoreceptor;
[0040] FIGS. 2A and 2B illustrate the stable expression of the pseudoreceptor EGFR-Ecoil by flow cytometry analysis ( FIG. 2A ) and by Western blot analysis ( FIG. 2B );
[0041] FIG. 3 illustrates the growth profile of 293E cells;
[0042] FIG. 4 illustrates an analysis of fiber-Kcoil transit-expression by western blot;
[0043] FIG. 5 illustrates the transduction of 293 and 293E cells by AdFK4m/GFP and Ad/GFP;
[0044] FIGS. 6A and 6B illustrates specific transduction of 293 and 293E cells by AdFK4m/GFP and Ad/GFP;
[0045] FIG. 7 illustrates the virus growth kinetics in cells 293E;
[0046] FIG. 8 illustrates immunoblot analysis showing the trimer form of modified-fiber;
[0047] FIGS. 9A and 9B illustrate the gene transfer profile of AdFK4m/GFP and AdK4mmRGD/GFP in 293 and 293E cells respectively; and
[0048] FIGS. 10A and 10B illustrate the gene transfer profile of AdFK4m/GFP and AdK4mmRGD/GFP in HeLa and A549 cells respectively.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0049] In accordance with the present invention, there is provided a new modified virus and its replicating cell. The idea behind the present invention for modifying the virus was to render the virus incompetent in duplicating in naturally-occurring cells, such as mammalian cells. Therefore the virus was modified to prevent binding to its natural receptors. However, without binding to its natural receptors on cells, the modified virus could not be reproduced or replicated. Thus, the virus was further modified to have a first artificial binding element of a binding pair, and a new cell was also constructed to have on its surface the other element of the binding pair. The binding pair was carefully chosen to have an appropriate affinity with each other to ensure efficient delivery of the viral vector.
[0050] Therefore, according to one aspect of the invention, two de novo-designed peptides (E-coil and K-coil), which interact with each other with high affinity were constructed to establish a new receptor-ligand system. These peptides each contains from 1 to 5 repeats of EVSALEK (SEQ ID NO: 1) and kVSALKE (SEQ ID NO:2) sequences, respectively. A pseudoreceptor, composed of E-coil fused with the transmembrane and cytoplasmic domains of EGFR was developed. 293 cells expressing such pseudoreceptor (293E) were shown to efficiently propagate a CAR-ablated AdV containing the complementary K-coil motif incorporated in. its fiber knob (AdFK4m). Furthermore, it has been shown herein that virus entry is mediated in a CAR-independent pathway via E-coil/K-coil interaction. Furthermore, the fiber of such modified virus could be further modified by the insertion of a ligand (RGD motif) for targeting to new tropism. These results demonstrate that the packaging cell line 293E and AdFK4m constitute a useful platform for the generation of re-targeted AdVs.
[0051] The new virus and its corresponding propagation cells constitute a useful tools in gene therapy and more particularly in cancer therapy. One skilled in the art will appreciate that a further ligand can be attached to the virus so as to retarget the virus to a specific cell that bears the receptor for this further ligand. This further ligand can be inserted in the virus through genetic manipulation for the virus to express this further ligand. Alternatively, the further ligand can be attached to a linker which would recognize the first element of the binding pair and bind thereto. In such an embodiment, the linker comprises for example the other element of the binding pair to which is attached the further ligand. Thus, the first element of the binding pair now binds in the presence of the linker to the other element of the binding pair exposing at the end of said linker the further ligand. In such an embodiment, the modified virus do not normally replicate in a natural environment, but requires the modified cells to replicate. Once replication is achieved to a desired level, a linker comprising the other element of the binding pair and the further ligand specifically chosen for a specific application is attached to the modified virus for targeting the virus to a specific type of cells determined by the further ligand chosen.
[0052] It will also be appreciated that specificity of the binding elements can be modified by either increasing the length of the sequence of the elements of by repeating in tandem the elements on the virus and at the surface of the modified cells or on the linker.
[0053] The present invention will be more readily understood by referring to the following example which is given to illustrate the invention rather than to limit its scope.
EXAMPLE I
[0000] Methods and Materials
[0000] Plasmids
[0000] pMPG-EGFR-Ecoil
[0054] The EGFR signal sequence was amplified by PCR with the primers 5′-ATMGMTGC GGCCGCATGC GACCCTCCGG GACG-3′ (SEQ ID NO:3) and 5′-GGACTAGTCT TTTCCTCCAG AGCCCG-3′ (SEQ ID NO:4), which allowed the insertion of a Notl site at the 5′ terminus and Spel site at the 3′ terminus. pcDNA3-ErB1 (Lenferink et al., J. Biol. Chem., 275(35), 26748-26753, 2000) was used as template. 6 His and E-coil sequence were amplified by PCR using the primers 5′-CTAGCTAGCC ATCACCACCA TCATCAC-3′ (SEQ ID NO:5) and 5′-CCGCTCGAGT GATCCTCCAC C-3′ (SEQ ID NO:6) with the insertion of Nhel site at the 5′ terminus and Xhol site at the 3′ terminus. pcDNA3-E5coil was used as template (De Crescenzo G, et al., J Mol Biol. 328(5): 1173-1183, 2003). The transmembrane and cytoplasmic parts of EGFR were amplified with the primers 5′-CCGCTCGAGC CGTCCATCGC CACTGGG-3′ (SEQ ID NO:7) and 5′-CGGATATCTC ATGCTCCMT AAATTC-3′ (SEQ ID NO:8) with the insertion of Xhol site at the 5′ terminus and EcoRV site at the 3′ terminus. pcDNA3-ErB1 was used as template. The three fragments were cut with appropriate enzymes and ligated, then inserted into Notl and EcoRV sites of the vector pMPG, which express both BFP and hygromycin-resistant genes from independent cassettes.
[0000] CMV-FBK3/K4/K5
[0055] The oligonucleotide 5′-GGATCTGGAT CAGGTTCAGG AGTGGATCC-3′ (SEQ ID NO:9) containing a linker of 5 gly-ser and BamHl site was inserted at C terminus of the fiber gene under the control of CMV5 promoter in pCMV-FB-BFP plasmid. K-coil sequences were amplified with the primers 5′-CGCGGATCCA AGGTATCCGC TTTAAAG-3′ (SEQ ID NO:10) and 5′ CGCGGATCCC AATTGTTACT CCTTCAGAGC ACT-3′ (for K3: SEQ ID NO:11), or 5′-CGGGATCCCA ATTGTTATTC CTTCMGGCT GACAC-3′ (for K4: SEQ ID NO:12), or 5′-CGGGATCCCA ATTGTTACTC TTTAMGTGCT GA-3′ (for K5: SEQ ID NO:13), using pcDNA3-K5coil (also referred to sometimes as pcDNA3-HaKR1) (De Crescenzo et al., J Biol Chem, 279(25): 26013-26018, 2004) as template, digested by BamHI then inserted in the BamHI site of previously constructed plasmid pCMV-FB-BFP. A Munl site was incorporated in the amplified K-coil sequences after the stop codon.
[0000] CMV-FK4m and pE4-FK4m
[0056] A quikchange site-directed mutagenesis kit (Stratagene) was used for the mutation of fiber at aa 408. CMV-FK4 was amplified using the primers 5′-ACCACACCAG CTCCAGAGCC TMCTGTAGA CTAAATGC-3′ (SEQ ID NO:14) and 5′-GCATTTAGTC TACAGTTAGG CTCTGGAGCT GGTGTGGT-3′ (SEQ ID NO:15), which contain the mutation. The PCR condition is 1 cycle of 30 seconds at 95C.° and 16 cycles of 30 seconds at 95C,°, 1 minute at 55C° and 25 minutes at 68C.°. The methylated and no-mutated parental DNA template was then digested by Dpnl, while the mutated neo-synthesized plasmids are unmethylated, therefore uncleaved by Dpnl. They were then amplified in DH5α bacterial cells after transformation. For pE4-FBK4m, the plasmid CMV-FBK4m was then cut by Mun1 and Nhe1, digested fragment containing the modified part of fiber gene was inserted into MunI and Nhel-digested pE4 plasmid, which contains Ad sequence (84,5 mu to 100 mu) including fiber gene. The modified part of the fiber replaced the wildtype (wt) fiber in pE4 plasmid.
[0000] pE4-FK4mmRGD
[0057] The plasmid pE4-FK4m is mutated at aa409 by quickchange site-directed mutagenesis kit as described for CMV-FK4m. The two primers used for this mutation are 5′-ACCACACCAG CTCCAGAGGC TMCTGTAGA CTAAATGC-3′ (SEQ ID NO:16) and 5′-GCATTTAGTC TACAGTTAGC CTCTGGAGICT GGTGTGGT-3′ (SEQ ID NO:17). This plasmid pE4-FK4mm is then used to create pE4-FK4mmRGD. A fragment containing RGD sequence at HI-loop of Fiber is constructed by 2 steps PCR: at first two fragments FA and FB were amplified using primers 5′-CCGGTCCTCC MCTGTG-3′ (SEQ ID NO:18) with 5′- CAGTCTCCGC GGCAGTCACA ACCTCCTGTT TCCTGTGTAC CG-3′ (SEQ ID NO:19) and 5′-TGTGACTGCC GCGGAGACTG TTTCTGCGGA GGTGACACM CTCCMGTGC A-3′ (SEQ ID NO:20) with 5′-GGCCMTTGT TATTATTCCT TCMGGCTGA CAC-3′ (SEQ ID NO:21). pE4-FK4mm was used as template. Then FA and FB, which contain overlapping sequences between them, were mixed together and amplified by PCR; the resulting fragment FC is composed by both FA and FB. FC was then digested by Nhel and Munl, and inserted into pE4-FK4mm cut by the same enzymes. Fragment FK4mm-RGD were also amplified by PCR, and inserted into plasmid pAdCMV5.
[0000] Cells
[0058] 293, HeLa and A549 cells were maintained in Dulbecco's Modified Eagle's Medium (DMEM) (Gibco), supplemented With 10% heat-inactivated calf serum. HeLa-rtTA and A549-tTA have been described previously (Massie B, et al., J Virol, 72(3): 2289-2296,1998).
[0059] Stable cell line 293E cells was generated by transfection of 293 cells with pMPG-EGFR-Ecoil/BFPq (5 μg). This transfection was done using the polyethylenimine (PEI) (7.5 μg) precipitation method. 48 h post-transfection, the cells were subjected to selection for 3 weeks with hygromycin (400μg/ml). The cells expressing the highest level of BFP reporter protein were distributed into 96-well plates and expanded under the selective pressure with hygromycin.
[0000] Viruses
[0000] Ad/GFP Viral Construction
[0060] AdEasy™ deleted in E1 and E3 regions (QBiogene) was used to produce Ad/GFP by homologous recombination with a transfer vector containing GFP gene under TR5/CuO promoter (Mullick, A., Konishi Y., Lau P., and Massie, B. A cumate-inducible system for regulated expression in mammalian cells (International publication WO02/088346). 100 ng of AdEasy and 1 μg of Pmel-linearized transfer vector were used for transformation of BJ5183 bacterial cells by electroporation (2.5 KV). The resultant Ad/GFP contains the reporter GFP gene in the E1 region.
[0000] AdFK4m Viral Construction
[0061] AdEasy deleted in E1 and E3 regions was cut with Munl, Pacl and Spel, and the digested fragments Munl/Pacl and Pacl/Spel were ligated with another fragment Munl/Spel derived from plasmid pE4-FK4m. This later plasmid contains Ad sequence (84.5 mu to 100 mu) including fiber gene, which has a mutation at aa 408 (S->E), and a K-coil sequence inserted at C-terminus.
[0000] AdFK4m/GFP Viral Construction
[0062] AdFK4m was used to produce AdFK4m/GFP by homologous recombination with a transfer vector containing GFP gene under TR5/CuO promoter 100 ng of AdFK4m and 1 ug of Pmel-linearized transfer vector were used for transformation of BJ5183 bacterial cells as described for Ad/GFP.
[0000] AdFK4mmRGD/GFP Viral Construction
[0063] pE4-FK4mmRGD. were cut by Kpnl and Pacl. 200 ng of digested fragments containing Fiber-RGD were cotransfected with 100 ng of AdEasyΔfibre/GFP digested by Srfl into BJ5183, the recombinant AdFK4mmRGD/GFP was then selected.
[0000] Rescue of Ad Viruses
[0064] 5 μg of viral DNA Ad/GFP and AdFK4m/GFP were cleaved with Pacl, then respectively transfected into 293E or 293 cells by PEI precipitation method. Cells were harvested after 21 days when they showed cytopathic effect. After three cycles of freeze-thaw to release Ad particles, 293E or 293 cells were infected with half of the cell lysate to propagate the viruses. The infectious titers were determined by measuring the GFP expression in 293E cells using flow cytometry (λ=525nm).
[0000] Proteins Expressing Analysis
[0065] 5 μg of DNA was used for cell transfection by PEI precipitation method. 48 h later, cells were collected, washed with phosphate buffered saline (PBS), lysed in 62.5 mM Tris-HCl (pH6.8), 10% glycerol, 2%SDS, 2.5% 2-mercaptoethanol (denaturing condition) or non-reducing buffer (the same buffer except 1%SDS without 2-mercaptoethanol, followed by sonication. 25-50 μg of total protein extract was loaded onto acrylamide gel. After transfer, the nitrocellulose membrane was blocked with PBS containing 5% dry milk, 0.1% tween 20™ during 1 h at room temperature, and then probed with a monoclonal antibody against EGFR (1:1000), fiber protein (1:500) (Neomarkers) or histidine (1:500) (Qiagen) overnight at 4° C. Proteins were then detected by using anti mouse peroxidase (1:5000) and the ECL™ chemiluminescence kit (Amersham).
[0000] Cytofluorometry
[0066] Cells were dislodged from tissue culture plate by cell dissociation solution (sigma), centrifuged at 1000 rpm, and resuspended at 1×10 6 cells/ml in complete medium containing 10% serum, then incubated with 10 μl antibody against to His, followed by incubation of 6 μl of Alexa green fluor 488 coat anti-mouse IgG (Molecular probes A-1100). Each incubation step was done during 1 h on ice. The cells were analyzed by FACScan™ cytometer at λ of 525nm.
[0000] Virus Transduction Assays
[0067] 5×10 5 Cells were seeded on 12-well plates and incubated with virus during 2 days at 37° C. Prior to infection, cells were incubated with or without K-coil peptide (2 μg) or soluble fiber protein (2 μg) in 200 μl DMEM medium for 1 h at 37° C. Peptides remained present during virus infection when 300p1 of virus were added. Transduction efficiency was evaluated by monitoring GFP expression by flow cytometry analysis.
RESULTS
[0000] Generation of a 293 Cell line (293E) Expressing a Pseudoreceptor (EGFR-Ecoil)
[0068] An artificial peptide E-coil (5 heptads of EVSALEK) was chosen for the construction of EGFR-Ecoil pseudoreceptor. Using such an artificial ligand should exclude the possibility of accidental in vivo binding of a modified AdV to receptors other than the selected target. Gene encoding the fusion protein EGFR-Ecoil ( FIG. 1 ) was cloned in a mammalian expression vector pMPG under the control of a modified CMV promoter. EGFR-Ecoil is composed of the signal sequence of EGFR, 6 His, E-coil sequence, the transmembrane and cytoplasmic parts of EGFR. The EGFR signal sequence directs Ecoil to the cell surface and the EGFR transmembrane domain anchors the receptor in the plasma membrane. The 6 His permit detection of the protein by immunoblot and flow cytometry analysis. The resultant plasmid contains also the gene for hygromycin selection and BFP (blue fluorescent protein) reporter expressed from independent cassettes.
[0069] Stable cell lines (293E) were generated by transfection of 293 cells with the plasmid pMPG-EGFR-Ecoil, followed by selection in the presence of hygromycin. The BFP positive cells were sorted using the multiwell automated cell deposition system and clonal distribution was visually checked.
[0070] Five of the best clones as assessed by BFP expression were further characterized for EGFR-Ecoil pseudoreceptor surface expression by flow cytometry of cells following incubation with the anti-His Ab. FIG. 2A shows the profile of the best clone displaying a marked increase in cell fluorescence (293E cells) as compared to 293 cells (without pMPG-EGFR-Ecoil). The median fluorescence for 293E cells was 732, versus 11 for 293 cells. Most of the other dories had a similar profile. This result demonstrated that the pseudoreceptors EGFR-Ecoil were displayed on the cell surface. In FIG. 2A , cells were detached by cell dissociation solution (sigma), resuspended at 1×10 6 cells/ml, and incubated with 10 ul of anti-his Ab, followed by the incubation of 6ul of anti-mouse Ab*. The fluorescence intensity is plotted on a logarithm scale on the x-axis. The empty peak represent 293 cells while the shadowed peak represent 293E cells.
[0071] The EGFR-Ecoil expression in two clones was confirmed by Western blotting using anti-EGFR-Ecoil antibody (anti-erb1), which can recognize the cytoplasmic part of EGFR. As shown in FIG. 2B , the expression of the pseudoreceptor is much stronger than the endogenous EGFR in 293E cells (line 2), while this pseudoreceptor is not detected in 293 parental cells (line 1). In FIG. 2B , 293 cells (1) and 293E cells (2) lysates were subjected to SDS-PAGE (10%), transferred to nitrocellulose, and probed with an anti-erb-1 antibody at dilution of 1:1000. The bands corresponding to EGFR and EGFR-Ecoil are identified.
[0072] The growth rate of the selected 293E cells was compared with. parental cells ( FIG. 3 ). Both cells showed similar profile, which indicate that the expression of EGFR-Ecoil pseudoreceptor did not significantly affected the cell physiology. In FIG. 3 , cells were seeded at 2×10 5 in DMEM medium supplemented with 10% of heat-inactivated fetal bovine serum, and counted on a daily basis until the monolayers reach confluency.
[0000] Construction of AdV Containing Chimeric Fiber Incorporating Kcoil in the knob (AdF4Km/GFP)
[0073] The artificial heptad K-coil (KVSALKE), which has high affinity to E-coil, was selected as the ligand to be inserted into the fiber knob of AdV. A crucial requirement for successful fiber modification by incorporation of a peptide is that this should neither change its conformation nor its normal function. Two questions have been therefore addressed: Is the 5 heptads (35 aa) segment of K-coil small enough to be incorporated into fiber without changing its trimerization, which is essential for fiber incorporation into the capsid and proper virus assembly? If the size of the K-coil motif was varied by eliminating 1 or 2 heptad sequences, will it then retain an affinity to E-coil peptide high enough to insure efficient binding of the AdV to the pseudoreceptor?
[0074] Different repeats of E-coil and K-coil have been synthesized and their interaction has been analyzed by BIACORE (De Crescenzo G, et al., Biochemistry, 42(6): 1754-1763, 2003). E5 (E-coil of 5 repeats) binds K5 (K-coil of 5 repeats) with very high affinity (Kd =63pM). The association capacity decreased with the number of the heptad: Kds are 14nM and 7 μM respectively for E5/K4 and E5/K3 interaction. Clearly, reducing the number of heptad by 2 in K-coil motif dramatically decreased it's binding to E-coil.
[0075] In the present invention, the suitable number of K-coil heptad was also investigated for their incorporation in fiber without disturbing the fiber trimerization. Chimeric fiber genes with 3, 4 or 5 heptads of K-coil motif (K3, K4 or K5) at the C-terminus were cloned respectively into the vector pAdCMV5K7BFP under the CMV5 promoter. In order to optimize the accessibility of the K-coil in fiber to the EGFR-Ecoil pseudoreceptor, a flexible linker made of 5 glycine residues was added between the fiber and K-coil. The recombinant proteins were analyzed by western blotting under denaturing ( FIG. 4 , lanes 1, 2, 4, 6, and 8) and non-denaturing conditions (lanes 3, 5, 7 and 9). In non-denaturing condition, the trimer forms of FB/K3 (lane 5) and FB/K4 (lane 7) are at same level as wt fiber (lane 3). In contrast, the overall expression of FB/K5 (lane 9) was dramatically decreased while its trimerization was slightly affected. Note that the anti-fiber antibody used in this western blot preferentially recognized the trimeric fiber. This result shows that, both 3 and 4 heptads of K-coil incorporated in fiber did not compromise the expression nor the trimerization of these proteins. In FIG. 4 , 293 cells were transiently transfected with pAd-CMV-GFP control plasmid (1), or plasmids expressing wt fiber (2 and 3), fiber/K3 (4 and 5), fiber/K4 (6 and 7) and fiber/K5 (8 and 9). Cells lysates in either denaturing (1, 2, 4, 6, and 8) or non-denaturing conditions (3, 5, 7 and 9) were run on SDS-PAGE (10%). The proteins were transferred to nitrocellulose, and detected by an anti-fiber antibody (1:500). At the left are shown the positions of molecular weight standards in kilodaltons.
[0076] Given its higher affinity for E-coil, K4 was selected as the ideal candidate to be inserted into virus capsid. An AdV was then constructed in which the fiber gene contained K4 at C terminus in addition to a mutation (S ->E) at aa 408 known to abolish the fiber interaction with CAR. This recombinant virus has also a reporter gene encoding for GFP in the E1 region (AdK4m/GFP). The viral DNA generated in E coi by homologuous recombination was transfected in 293E cells to produce the virus. A control virus Ad/GFP that contains wt fiber and GFP under the same promoter was also constructed.
[0000] Transduction of 293E Cells by AdF4Km/GFP
[0077] In order to test whether the membrane-anchored EGFR-Ecoil could serve as an artificial receptor for AdFK4m/GFP, both 293 and 293E cells were infected with this virus at MOI of 0.01; 0.05; 0.5, or 0.8. Although GFP expression is controlled by the tetracycline-regulated promoter in the expression cassette, due to leaky expression of the promoter and massive gene amplification following replication, GFP expression was easily detectable in 293 cells without the tetracycline trans-activator (tTA) as previously shown (Massie B, et al., J Virol, 72(3): 2289-2296, 1998). Transduction efficiencies were evaluated two days later by measuring GFP expression in infected cells using flow cytometry analysis. As shown in FIG. 5 , 293 cells without the pseudoreceptor are barely transduced by AdFK4m/GFP, in contrast to the wt Ad/GFP, especially at low MOls. In FIG. 5 , cells were infected with equal amounts of virus particles as indicated, 48 h later, GFP expression in infected cells was analyzed by flow cytometry. This result is consistent with the expected reduced transduction efficiency of AdFK4m/GFP with the fiber mutation at aa 408. In sharp contrast, the transduction efficiencies in 293E cells of AdFK4m/GFP, as compared with 293 cells, were increased 7-fold at MOI of 0.01, 24-fold at MOI 0.05, 11-fold at MOI 0.5 and 8-fold at MOI of 0,8, and they reach the same transduction level as wt virus Ad/GFP. As expected, the control Ad/GFP infects 293E cells at the same level as 293 cells._These results indicated that AdFK4m/GFP infects 293E cells via a CAR-independent cell entry pathway. The expression of trimer form of modified-fiber in infected 293E cells was confirmed by immunoblot.
[0078] Competitive inhibition assays were performed in order to confirm that 293E transduction by AdF4Km/GFP required the specific binding of the Ad vector to the pseudoreceptor via E-coil/K-coil interaction. In FIG. 6A and 6B, 293 (Black bar) and 293E (Grey bar) cells were infected with AdFK4m/GFP or Ad/GFP at a MOI of 0.05. Prior to addition of virus, cells were incubated for 1 h with 0 or 2 μg of K-coil soluble peptide (6A) or soluble Ad5 fiber (6B). GFP expression was monitored by flow cytometry analysis at 48 h pi. When cells were pre-incubated with K-coil, AdFK4m/GFP mediated GFP gene transfer in 293E cells was inhibited by 80% while no effect was observed for the transduction of 293 parental cells. For the control virus Ad/GFP meditated-transduction, no inhibition was observed in either 293 or 293E cells ( FIG. 6A ). By contrast, fiber inhibits the Ad/GFP transduction in both 293 and 293E cells, while it has not any effect for AdFK4m/GFP mediated-transduction in 293E cells ( FIG. 6B ). These results clearly demonstrated that binding of AdFK4m/GFP to the pseudoreceptor via E-coil/K-coil interaction mediates virus infection to 293E cells in the absence of fiber-CAR interaction.
[0079] In conclusion, the complementary components consisting of modified Ad virion and cell line together constitute a novel system that permits the fiber receptor-independent propagation of tropism-modified AdVs.
[0000] Characterization of Virus Growth Kinetics
[0080] Virus growth rate of the modified virus AdFK4m/GFP were tested in comparison with Ad/GFP ( FIG. 7 ). 293E cells were infected at an MOI of 2 active virus particles/cell with both virus, and the titers were determined by measuring the GFP expression at 1, 2, and 3 days post-infection. In FIG. 7 , on day 0, 293E cells were infected with Ad/GFP or AdFk4m/GFP at MOI of 2. At days 1, 2, or 3 post-infection, the cells were harvested and freeze-thawed, the infectious particles titers, which were expressed as GTU (GFP Transfer Unit) 1 ml of cell lysate, were determined measuring the GFP expression flow cytometry analysis. The growth curves for both virus showed similar shapes and no lag was observed in recombinant virus growth. However, the production of infectious modified virus was inferior to the virus with wt fiber. This could be due to suboptimal level of expression of the EGFR-Ecoil pseudoreceptbr in 293E cells or to suboptimal expression of K4-fiber in AdFK4m/GFP.
[0000] Gene Delivery by Genetically Modified-Ad Vector
[0081] Having generated a CAR-ablated AdV with a K-coil modified fiber and 293E cells for its amplification, a tropism-modified virus was then constructed. As an example, RGD motif was inserted into the HI-Loop of fiber in order to target virus to cellular proteins integrina. At same time, the aa409 of fiber-RGD was also modified (P->A) to further ablate fiber's interaction with it's natural receptor CAR. The trimerization of this modified-fiber was tested by immunoblot after transient transfection of 293 cells ( FIG. 8 ). In FIG. 8 , plasmids allowing the expression of wt fiber (1 and 2), RGD (3 and 4)-containing fiber were transfected into 293 cells, 48 h later, the trimer form of fiber-expression (1 and 3) was detected as described in FIG. 4 . The FK4mm-RGD modified fiber (lane 3) showed same trimer expression level as the wild-type fiber (lane 1). The AdK4mmRGD/GFP virus was then produced by transfection of 293E cells.
[0082] The effect of RGD incorporation in the modified fiber (FK4mm-RGD) was first tested by measuring the gene delivery efficiency of AdFK4mmRGD/GFP in E1-complementing cells. AdFK4mmRGD/GFP was incubated at different MOls with 293 ( FIG. 9A ) and 293E ( FIG. 9B ) cells, and GFP expression was analyzed by flow cytometry 2 or 3 days later as a measure of transduction efficiency. As compared with the CAR-ablated virus AdFK4m/GFP, AdFK4mmRGD/GFP showed, in 293 cells, a significant increase in GFP expression, especially at lower MOI, indicating that gene delivery was improved by the addition of RGD in the modified fiber. In Ecoil-containing 293E cells, AdFK4mmRGD/GFP transduced 2 to 3 times better than AdFK4m/GFP at both MOls used. As expected, the transduction level in 293E cells is higher than 293 cells, since the virus can also enter into cells via the pseudoreceptor EGFR-Ecoil.
[0083] AdFK4mmRGD/GFP's transduction efficiency was also tested in cells that do not support virus replication (HeLa and A549) ( FIGS. 10A and 10B ). In FIGS. 10A and 10B , 5×10 5 HeLa-rtTA ( 10 A) and A549-tTA cells ( 10 B) were infected, with equal amounts of virus particles AdFK4mmRGD/GFP and AdFK4m/GFP at indicated. MOls. The resulting GFP expression (y axis) was analyzed by flow cytometry 2 days later. Detection of GFP expression in such cells was facilitated by the expression of the tetracycline-inducible transactivators (tTA or rtTA). In both cell lines the transduction efficiency of AdFK4mmRGD/GFP was increased by a factor 3 to 6 fold as compared to AdFK4m/GFP depending on the MOI ( FIGS. 10A and 10B ). Taken together, these results demonstrated that the modified vector AdFK4mmRGD/GFP restore the cell transduction via the RGD motif-added in fiber.
[0084] In conclusion, the complementary components comprising modified Ad virion and cell line together constitute a novel system that permits the fiber receptor-independent propagation of tropism-modified AdVs. One of the main advantages of this system is the possibility of re-targeting, either through direct incorporation of ligands in the capsid, or through the construction of adapters (coil-fused ligands).
[0085] While the invention has been described in connection with specific embodiments thereof, it will be understood that it is capable of further modifications and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth, and as follows in the scope of the appended claims. | In accordance with the present invention, there is provided a modified virus ablated of its natural receptors interactions with an unmodified or non-naturally occurring cell, said modified virus comprising a non-native polypeptide, said modified virus having an altered tropism conferred by said non-native peptide, and replicating only in cells that can interact with said non-native peptide, said virus being incapable of infecting a cell through a CAR-dependent entry pathway. There is also provided a modified cell line for replicating the modified virus. These two together can be advantageously put into practice in the field of medicine and more particularly in gene therapy. | 2 |