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throughout the following description specific details are set forth in order to provide a more thorough understanding of the invention . however , the invention may be practiced without these particulars . in other instances , well known elements have not been shown or described in detail to avoid unnecessarily obscuring the present invention . accordingly , the specification and drawings are to be regarded in an illustrative , rather than a restrictive , sense . the invention in one embodiment is directed to implantable medical devices with a flexible thin film calcium phosphate bio - compatible and bio - resorbable coating that has the ability to act as a high capacity drug carrier . such cap coatings have no side - effects during coating dissolution into body fluids , and can be designed with a high level of control of coating dissolution rate and microstructure , which also determine the drug retention and release characteristics . of all the types of implantable medical devices that exist , the coronary stents utilized in balloon angioplasty procedures provide a useful model for testing the effectiveness of sol - gel deposited thin flexible cap coatings on such stents due to the fact that such stents are designed to be flexible . the use of such stents in the examples below should not , however , be considered as limiting the application of the cap coatings described only to stents . the invention has broad application to virtually any type of body implantable device . we have determined unexpectedly that the intrinsic brittle behaviour of cap ceases to limit the system strain capability if the strongly bonded coating is sol - gel deposited and is thinner than approximately 0 . 001 mm . experiments involving repeated contraction / expansion of such thin cap sol - gel coated stents reveal that there is no separation of the coating from the stent , nor visible damage to the coating , if the coating is thinner than about 0 . 001 mm and is strongly bonded to the substrate ( the tensile bond strength should be larger than about 40 mpa , as measured in model strength experiments according to astm c - 633 standard ). in addition , we have discovered that if the novel sol - gel process for deposition of calcium phosphates , in particular hydroxyapatite ( ha ) synthesis ( as previously disclosed in our u . s . pat . no . 6 , 426 , 114 b1 , jul . 30 , 2002 , “ sol - gel calcium phosphate ceramic coatings and method of making same ”, by t . troczynski and d . liu ) is used , the resulting thin flexible coating has controlled porosity which may be utilized to retain drugs within the coating , and release the drugs at a controlled rate . the invention pertains to a sol - gel ( sg ) process for synthesis of calcium phosphate , in particular , hydroxyapatite ( ha ), thin film coatings on implantable medical devices . the process allows the ha to be obtained in a controlled crystallized form , at a relatively low temperatures , i . e . starting at ≈ 350 ° c . this is an unexpectedly low crystallization temperature for ha sol - gel synthesis . the process provides excellent chemical and physical homogeneity , and bonding strength of ha coatings to substrates . the low process temperature avoids substrate metal degradation due to thermally - induced phase transformation , microstructure deterioration , or oxidation . disclosed herein is a method wherein uniform films of hydroxyapatite by the electro - phoretic deposition ( epd ) method ( epd - ha ) are deposited on complex stent surface , and there is no need to pursue sintering in excess of 500 ° c . to achieve substantial structural integrity of the film and its high bonding strength to the metallic substrate . in this method , the first step is the well - known epd of the ha film , for example as disclosed in u . s . pat . no . 5 , 258 , 044 , using suspension of sub - micrometer particles of ha in water . this film is dried and then heat treated at 500 ° c . for 10 - 60 minutes to initiate sintering of ha . the film is still too weak and too poorly bonded for practical use as a coating on stent or other medical device or implant , but is sufficiently strong to survive the subsequent processing step comprising impregnation by aero - sol - gel ha droplets . the droplets penetrate porosity of the previously deposited epd - ha , strongly aided by the capillary suction . thus , majority of the pores of the epd - ha film are penetrated by the sol - gel precursor of ha , all the way to the metallic substrate . this composite film can be now dried and sintered at a relatively low temperature or 400 - 500 ° c ., due to the very high activity of the sol - gel component of the film . the sol - gel film bonds the particles of ha deposited by epd , and bonds well to the metallic substrate during the heat treatment thus , both the film uniformity ( due to epd process ) and low - temperature sinterability ( due to sol - gel process ) have been achieved . this novel and inventive hybrid technology for uniform ha coatings on stents has the ability to produce films in thickness range from about 1 micron to above 100 microns , with porosity in the range from about 10 vol % to about 70 vol %. such porous thick ha films are excellent carriers for drugs loaded through impregnation into open porosity of the film . details of such hybrid process , and its several variants , for preparation of ha films on stents , are given in the examples below . problems with drug delivery in vivo are frequently related to the toxicity of the carrier agent , the generally low loading capacity for drugs , and the aim to control drug delivery resulting in self - regulated , timed release . with the exception of colloidal carrier systems , which support relatively high loading capacity for drugs , most organic systems deliver inadequate levels of bioactive drugs . sol - gel films heat - treated at relatively low temperatures closely resemble the properties of colloidal films , in terms of accessible surface area and porosity size . the sol - gel process according to the invention allows the calcium phosphate to be obtained in a crystallized form , at relatively low temperature , i . e . approximately 350 - 500 ° c . variation of the heat treatment temperature and time provides for control of coating crystallinity ( i . e . a more amorphous , more easily resorbable coating can be processed at lower temperatures ) as well as coating porosity ( higher porosity and smaller average pore size at lower temperatures ). variation of ca / p ratio in the sol - gel precursor mix allows one to obtain various calcium phosphate phases , for example , hydroxyapatite , dicalcium phosphate , tricalcium phosphate or tetracalcium phosphate . the invention in one embodiment is directed to a sol - gel process for preparing calcium phosphate , such as hydroxyapatite , which comprises : ( a ) hydrolysing a phosphor precursor in a water or alcohol based medium ; ( b ) adding a calcium salt precursor to the medium after the phosphite has been hydrolysed to obtain a calcium phosphate gel such as a hydroxyapatite gel ; ( c ) depositing the gel on the surface of an implantable medical device ; and ( d ) calcining the calcium phosphate , such as hydroxyapatite , at a suitable elevated temperature and for pre - determined time to achieve desired crystallinity , bonding and porosity characteristics for the coating on the device . the deposition of the gel can be done by any number of methods , such as aero - sol deposition , dip - coating , spin - coating , electrophoretic deposition . in a preferred embodiment , the phosphor precursor can be an alkyl phosphite and the alkyl phosphite can be triethyl phosphite . further the calcium precursor can be a water - soluble calcium salt and the water soluble calcium salt can be calcium nitrate . the crystallized calcium phosphate can be calcined at a temperature of at about 350 ° c . or higher . the metallic implantable medical device can be stainless steel , cobalt alloy , a titanium substrate or other metallic alloy substrate . we have discovered that if certain specific characteristics of the calcium phosphate coatings are maintained , the coatings become highly flexible while maintaining their chemistry , high bio - compatibility , and bio - resorbability . the most important characteristics are ( a ) coating thickness , and ( b ) the strength of the coating bonding to the metallic substrate . we have repeatedly demonstrated ( refer to the examples below ) that if cap coating thickness is maintained below about 0 . 001 mm , and its bonding strength to the metallic substrate is above approximately 40 mpa , the substrate - coating system retains the strain capabilities of the substrate alone , i . e . the system maintains its integrity during deformation . furthermore , we have discovered that thicker cap coatings deposited discontinuously on metallic substrate , i . e . in the form of separate “ islands ” and “ patches ” approximately 1 - 100 μm in diameter , retain high resistance against substrate deformation . our experiments have shown that stents coated with such 1 - 100 μm patches , about 1 - 10 μm thick , can be crimped and then expanded without damage to the patches of ceramic . these patches can be deposited on the substrate through a variety of methods discussed above , such as bm - ha , ecd - ha , cpc - ha ( all at room or near - room temperature ), or epd - ha , sg - ha and combinations thereof ( these two techniques including heat treatment at elevated temperatures ). these coating deposition techniques are illustrated in the following examples . the discontinuous cap film coated medical implant may have some fraction of an area of the metallic substrate exposed to living tissue , which may again lead to the adverse tissue reaction described above . this problem can be avoided by combining discontinuous cap films with a continuous bio - compatible and non - thrombogenic polymer . thus , a composite cap - polymer coating on medical implant is the result . furthermore , a thin (& lt ; 0 . 001 mm ) continuous cap coating can be combined with a thicker discontinuous cap coating . the effects of this process ( described in detail in the examples ) are shown in the representative fig1 and 2 . fig1 a illustrates stainless steel ( 316l ) stent coated with discontinuous asg - ha thin film ; fig1 b is a magnification of the sector of ( a ) indicated by the rectangle . fig2 a illustrates a stainless steel ( 316l ) stent coated with discontinuous asg - ha thin film and crimped , with no damage to the coating . fig2 b is the same stent after expansion , showing no damage to the coating . our discovery of flexible continuous / discontinuous cap films or cap / polymer films opens up a range of new applications of highly biocompatible cap coatings for medical implants , particularly , but not limited to those that require deformation capability such as coronary stents . a sol - gel ( sg ) process provides superior chemical and physical homogeneity of the final ceramic product compared to other routes , such as solid - state synthesis , wet precipitation , or hydrothermal formation . the sg process allows the desired ceramic phase , e . g . thin film cap coating , to be synthesized at temperatures much lower than some of the alternate processes . in the sg coating process substrate metal degradation due to thermally induced phase transformations and microstructure modification or oxidation , is avoided . sg widens green - shaping capability , for example , and it is a very convenient method for deposition of thin ceramic coatings . sol - gel deposition of ha ( sg - ha ) films at elevated temperatures ( 350 - 500 ° c .) was disclosed previously in u . s . pat . no . 6 , 426 , 114 b1 . sol - gel ( sg ) processing of ha allows molecular - level mixing of the calcium and phosphor precursors , which improves the chemical homogeneity of the resulting calcium phosphate . the crystallinity of the calcium phosphate phase can be enhanced by appropriate use of water treatment during processing . variation of ca / p ratio in the sol - gel precursor mix allows one to obtain any of a number of calcium phosphate phases , for example , hydroxyapatite , dicalcium phosphate , tricalcium phosphate or tetracalcium phosphate . the versatility of the sg method provides an opportunity to form thin film coatings , either continuous or discontinuous , in a rather simple process of dip - coating , spin - coating or aero - sol deposition . a high degree of ha crystallinity is frequently required for longer - term bioactive applications , because partially crystalline , or amorphous calcium phosphate , such as ha , coatings are rapidly resorbed by living tissue . for the presently disclosed application of thin ha films on implantable medical devices , control of crystallinity of the ha coating is possible through variation of the time / temperature history during processing . this allows control of the coating resorption rate and thus rate of release of the drugs impregnated into microporosity of the coating . ceramics produced by sol - gel processing can be designed to include high fraction of pores , with well - defined ( narrowly distributed ) pore size . this is a consequence of the chemical route to the final oxide ceramic produced through sg . only a small fraction of the original precursor mass is finally converted to the ceramic oxide , the remaining fraction being released during heat treatment , usually in the form of gas , is usually as a combination of water and carbon dioxide . thus , the released gases leave behind a large fraction of porosity , up to 90 % in some instances , depending on the drying conditions and heat treatment time and temperature . these pores can be as small as several nm in diameter , again depending on the drying conditions and heat treatment time and temperature . effectively , the accessible surface area of such sol - gel derived oxide ceramics can reach several hundred square meters per gram of the oxide , making it an excellent absorbent of gas or liquid substances , or solutions . for example , the average pore size in sol - gel ha treated at relatively low temperature of 400 ° c . is about 5 nm in diameter , with 90 % of pore diameters falling within the range of 1 - 30 nm . this unique porosity characteristic is widely utilized to produce desiccants , filters and membranes of sol - gel derived ceramic . in this respect sol - gel derived ceramic oxides have a great advantage over polymers , which are in general difficult to process to possess high porosity and high accessible surface area . in the present invention , we utilize this unique property of sol - gel derived cap coatings on medical implants , especially stents , possessing high accessible surface area to make it a high - capacity drug carrier . in the text of this application , it is understood that when appropriate , the term “ calcium phosphate ” ( cap ) is used generically and includes minerals such as hydroxyapatite , dicalcium phosphate , tricalcium phosphate , tetracalcium phosphate and amorphous or partially amorphous calcium phosphate . studies on the sol - gel route to thin film calcium phosphate coatings on implantable medical devices , particularly stents , performed by the inventors have led to an unexpected break - through in process development . the method according to the invention has produced cap coatings after heat treatment in air , starting at about 350 ° c . we have unexpectedly discovered that the film is highly flexible if it is thinner than about 0 . 001 mm , thereby allowing damage - free manipulation of a cap coated deformable implantable medical device , for example the contraction and expansion of a cap coated stent . preferably , the coating has a thickness between about 0 . 0001 and 0 . 001 mm . furthermore , in this application , we have discovered that the film can accept drugs into its fine porosity , thereby allowing it to address the adverse phenomena related to common medically implanted devices , i . e . the restenosis that occurs after placement of a coronary stent in a blood vessel . the calcium phosphate coating according to the invention has been deposited on stents and other metallic surfaces using variety of techniques , including dip - coating , spin - coating , aero - sol deposition electrophoretic deposition . the coatings were deposited on stents made of 316l stainless steel and tubes , and on other metallic substrates including cobalt - iron alloy and titanium . to demonstrate the feasibility of the unique processing concepts outlined above , the following examples are described below for stainless steel substrate and coronary stents . the procedures outlined below can be applied to other implantable medical devices . in the first stage of the process , phosphite sol was hydrolysed in a water - ethanol mixture ( a concentration of 3m ) in a sealed beaker until the phosphite was completely hydrolysed ( which is easily recognized by loss of a characteristic phosphite odour ), at ambient environment . a ca salt ( 2m ) was then dissolved in anhydrous ethanol , and the solution was then rapidly added into the hydrolysed phosphite sol . the sol was left at ambient environment for 8 hours , followed by drying in an oven at 60 ° c . as a result of this process , a white gel was obtained . for the sol containing ca / p ratio required to produce ha , the gel showed a pure ( single phase ) apatitic structure with a ca / p ratio of 1 . 666 , identical to stoichiometric ha , after calcining at a temperature as low as 350 ° c . varying the ca / p ratio allows other calcium phosphates , such as dicalcium phosphate ( ca / p = 1 ) or tricalcium phosphate ( ca / p = 1 . 5 ), to be obtained . a coating produced using this process , and applied to 316 ss substrate , showed adhesive strength of about 40 mpa after curing at a temperature & lt ; 450 ° c . the coating was crack - free and porous . in another variant of the process , a pure water - based environment was used . the aqueous - based sols were prepared in the same manner as described above in example 1 for the ethanol - based system . a higher rate of hydrolysis of the phosphite sol was observed . the mixed sol was dried while stirring . after 8 hours aging , a white gel appeared . for the sol containing a ca / p ratio required to produce ha an apatitic structure with ca / p ratio of 1 . 663 , close to stoichiometric ha , resulted after calcining the gel at a temperature of 350 ° c . both the ethanol - based and aqueous - based gels showed essentially the same apatitic structure at relatively low temperatures . this invention provides a method of synthesizing the ha ceramics via an aqueous - based sol - gel process . a cap coating was deposited on the surfaces of a group of electropolished stainless steel stents through aerosol - gel processing . the stents were first treated in 2 . 4 n phosphoric acid solution for 10 minutes at 70 ° c . to clean the surface and produce microroughness for increased bonding of the coating . the treated stents were ultrasonically cleaned and dried . the cap sol was prepared by ( a ) hydrolysing a phosphor precursor ( phosphite ); ( b ) adding a calcium salt precursor to the medium after the phosphite has been hydrolysed to obtain a calcium phosphate sol such as a hydroxyapatite sol . the sol was atomized into ˜ 4 μm large particles using ultrasonically assisted atomizer , and the resulting aerosol fed into a coating chamber . this specific deposition technique is referred to as aero - sol - gels ( asg ) deposition and the resulting hydroxyapatite film as asg - ha . the clean stent was inserted into the coating chamber filled with flowing cap aerosol - gel for a period of 30 seconds , while maintaining the aerosol flow at 0 . 1 liter / min and chamber temperature at 50 ° c . the temperature of the coating chamber affects the deposition mode of the coating , producing a uniform , film like coverage of the surface as evidenced by sem . the coating was dried at 60 ° c . and heat treated at 450 ° c . for 15 min to crystallize cap to form hydroxyapatite thin film . the procedure produces a thin coating covering uniformly the surface of the stent . the thickness of the coating is measured using ellipsometry in the range of 50 - 150 nm . the subsequent sem studies on the crimped and expanded coated stents show no evidence of cracking or delamination of the coating . this proves the reliability of the uniform , thin continuous cap coating during the deployment and implantation of the stent into the coronary artery . cap coating has been deposited on the surface of an electropolished stainless steel stents through aerosol - gel processing ( asg ), as described in example 3 . the chamber temperature was maintained at 25 ° c . the coating was dried at 60 ° c . and heat treated at 450 ° c . for 15 min to crystallize cap to form hydroxyapatite thin film . the procedure explained above produces a coating comprising of isolated island of approximately 2 - 6 μm in size and 0 . 1 - 2 μm in thickness , scattered uniformly on the surface of the stent , and covering about 70 % of the surface of the stent , as shown in fig1 a and 1b . subsequent sem studies on the crimped and expanded coated stents showed no evidence of cracking or delamination of the coating , as shown in fig2 a and 2b . this proves the reliability of the discontinuous cap coating of variable thickness during the deployment and implantation of the stent into the coronary artery . stainless steel metallic substrates ( 316l ) were coated with a 0 . 6 - 0 . 8 μm thin layer of apatite ( asg - ha ) as described in example 3 . one group of samples was annealed at 400 ° c . for 20 min to achieve crystalline sg - ha ( c ) film and another group at 375 ° c . for 60 min to achieve amorphous sg - ha ( a ) film . these films were used as nucleation site for precipitation of bm - ha film . the sg - ha coated samples were immersed into “ simulated body fluid ” ( sbf ) of ionic composition ( in units of mmol / l ) 142 na + , 5 . 0 k + , 2 . 5 c 2 + , 1 . 5 mg 2 + , 103 cl − , 25 hco 3 − , 1 . 4 hpo 4 2 − , and 0 . 5 so 4 2 − . the sbf was buffered at ph 7 . 4 with tris ( hydroxymethyl )- aminomethane and hcl . this in - vitro static deposition ( i . e . the sbf was not renewed during the deposition period ) at ˜ 24 ° c . produced good quality , dense 3 - 5 μm thick bm - ha film deposits on flat sg - ha substrates . the crystalline sg - ha ( c ) film is coated with dense bm - ha , whereas amorphous sg - ha ( a ) film is coated with porous bm - ha . the properties of the underlying sg - ha surface modification film can be used to vary the properties , e . g . porosity , of the nucleated and deposited top bm - ha film for drug encapsulation . stainless steel metallic stents ( 316l ) were coated with − 0 . 1 μm thin cap coatings as described in example 3 . an inorganic colloidal slurry containing calcium phosphate precursor ca ( oh ) 2 and calcium phosphate salt monocalcium phosphate anhydrate , was ball milled in ethanol . the two starting inorganic ingredients had particle size 0 . 3 - 2 μm and 0 . 5 - 4 μm , respectively . the initial ca / p ratio in the slurry was kept at 1 . 5 . as dissolution and precipitation are the principal mechanisms for apatite development in such system , 5 wt % of submicron , crystalline hydroxyapatite powder was used as seeds for heterogeneous nucleation of cpc - ha . the thin cap film surface - modified sample was dip coated in the ethanol suspension of the precursors . after single dip coating , an approximately 10 μm thick layer of porous precursor powder mixture developed on the substrate due to rapid evaporation of ethanol . due to the colloidal nature of the precursors slurry , this film develops sufficient structural integrity ( i . e . strength and hardness ) to accept the next processing step . in this step , the film is exposed to sodium phosphate water - based solution ( 0 . 25 m ), which is allowed to soak into the open pores of the film , and then placed in an incubator at 37 ° c ., 100 % relative humidity , for 24 h . during incubation , the colloidal precursors react with the phosphate liquid and precipitate ha . in order to assess the possibility of using this double - coating route for controlled drug release , amethopterin ( sigma chemicals , usa ) was employed as a model drug , in an amount of 5 % based on solid phase content of cpc - ha precursors . the drug was mixed with the colloidal suspension of the precursors , before dip coating was performed . during incubation period , 20 μm thick cpc - ha coating precipitated encapsulating the drug molecules within the nanopores of the crystallizing ha . after encapsulation , a drug release study was conducted by immersion of the substrates into 20 ml of phosphate buffer saline ( pbs , ph = 7 . 4 ) at constant ratio of ( cpc coating weight )/( volume of pbs ) of 1 mg / ml . a reference sample coated with hydrogel film was also tested for drug release kinetics . the hydrogel film was prepared by dipping the cpc - ha layer containing the drug into a polymer solution containing 3 % polyvinyl alcohol . after drying , the weight gain of the ˜ 20 mg cpc - ha layer due to the additional hydrogel coating was ˜ 0 . 5 mg , corresponding to the content of polymer film in the cpc - ha matrix of about 2 . 5 %. the samples of pbs liquid with released drug were periodically taken out ( i . e . entire liquid was emptied ) and refilled with the same amount of 20 ml of pbs . the drug concentration in the supernatant was determined via an uv - visible spectroscopy . although a burst effect was detected for both coatings over the initial period of about 8 h , a slower release is evident for the sample post - coated with hydrogel . a linear relationship was obtained between the amount of drug released and ( time ) 1 / 2 for the release time greater than 8 h . the stent was submerged into water - based , diluted suspension of sub - micron particles of hydroxyapatite , containing approximately 2 wt % of ha in the suspension . dc voltage of 5v was applied to the stent , for times varying from 5 seconds , to 10 minutes . as the particles of ha naturally attain positive charge in such solution , they are attracted to the stent surface which is also a negative electrode ( cathode ) in this system . the buildup of ha particles attracted to the stent ( cathode ) allows to produce an extremely uniformly coated surface , thickness of the coating varying as a function of time of application of voltage . the film uniformity is the biggest advantage of such electro - phoretic deposition ( epd ) processing , which is difficult to reproduce using other methods such as sol - gel processing . for the short time of 10 sec ., the epd - ha coating thickness is about 1 micrometer . this type of epd - ha coating on 316l stainless steel stent is illustrated in fig3 . for the longer times of several minutes , the coating thickness may exceed 10 micrometers . thus , in this epd process , a controlled thickness , uniform ha film may be produced . the as deposited film constitutes loosely bonded particles of ha , of porosity generally in excess of 50 vol %. in order to increase structural integrity and bonding strength to the substrate of such epd film , heat treatment is necessary at temperatures at least 500 ° c ., for times at least 10 minutes . the heat treatment of epd films proceeds at higher temperatures and longer times than sol - gel films , because ha particles deposited in the epd process are less reactive than those deposited in the sol - gel process . the goal of such heat treatment is to increase interparticle bonding , while providing sufficient residual porosity to maintain low stiffness and flexibility of the film , and to provide room for drug impregnation . the need for higher temperature and longer times heat treatment of epd films is a disadvantage , as the heat treatment process may adversely affect properties of the metallic substrate of the stent . the ha was deposited on a 316l stainless steel stent surface through epd process as described in the example 7 . the uniformly deposited epd film was heat treated at 500 ° c . for 10 minutes to achieve minimal structural integrity of the film , sufficient to survive handling and preventing re - fluxing of the film upon contact with liquid medium . such epd - coated stent was exposed to droplets of sol in the aero - sol - gel process described in example 3 . the sol droplets have penetrated open porosity of the epd film , and , by capillary attraction , located themselves mostly within negative curvature of the necks between epd deposited ha particles . such composite coating was heat treated again at 500 ° c . for 10 minutes . now the active sol - gel component of the coating allowed achieving high structural integrity of the film , while epd component of the coating allowed achieving high uniformity of coverage by the film . a uniform , porous ha film was achieved in this novel combined process . the electrochemical deposition ( ecd ) of hydroxyapatite ha has been conducted in the mixed aqueous solution of ca ( no 3 ) 2 4h 2 o and nh 4 — h 2 po 4 . in this process ha is deposited on the cathodic ( negatively biased ) surface of stent or implant by the following reaction : 10ca 2 + + 6po 4 3 − + 2oh → ca 10 ( po 4 ) 6 ( oh ) 2 ecd was conducted in the mixed aqueous solution of 0 . 02329 m ca ( no 3 ) 2 4h 2 o and 0 . 04347 m nh 4 h 2 po 4 . the stainless steel specimen , i . e . stent , was the cathode , and platinum was used as the anode . the ph was controlled at 4 . 0 with the addition of sodium hydroxide . the environment temperature was controlled at 40 ° c .± 1 ° c . the coating morphology deposited at low current density ( 1 ma / cm 2 ) was a thin uniform porous structure , 1 - 2 micrometers thick for deposition time of 0 . 5 - 1 minute , as illustrated in fig4 . the ha was deposited on a 316l stainless steel stent surface through asg - ha process as described in the example 4 . the discontinuous network of ha patches left some of the stent surface uncoated . 5v dc bias voltage was applied to such pre - coated stent , and the stent submerged into suspension of submicron ha particles . the uncoated metallic surface of the stent preferentially attracted ha particles leading to preferential electrophoretic deposition ( epd ) of ha in these areas , to build the coating about 1 micrometer thick in about 10 seconds . the coated stent was heat treated at 500 c for 10 minutes . the epd - ha coated areas show increased porosity as compared to asg - ha coated areas , suitable for impregnation with drug carrying liquid . such composite engineered ha coating shows unique properties regarding mechanical performance and drug release properties . the ha was deposited on a 316l stainless steel stent surface through asg - ha process as described in the example 3 , followed by the process of ecd - ha deposition as described in example 9 , but on top of the already heat treated asg - ha . such composite engineered coating allowed to achieve substantially higher bonding strength ( as compared to ecd - ha deposited directly on metallic surface ), and capability of drug encapsulation during deposition of ecd - ha on top of asg - ha . the ha was deposited on two 316l stainless steel stents surface through asg - ha process as described in the example 4 . the coated stents were evaluated in the standard thromboresistance test in dogs . minimal thrombosis with a grade of 1 ( defined as thrombus found at one location only ) was observed in one out of two test sites . in the second test site , no thrombosis ( grade 0 ) was observed . the process for coating of calcium phosphate , in particular ha , bioactive ceramics , on implantable medical devices disclosed herein offers the following advantages in comparison to other processes and other coating materials on implantable medical devices : ( 1 ) the coating process , including cap sol synthesis , can be completed in ambient environment ( i . e . air ), in less than 24 hours . ( 2 ) the thin (& lt ; 0 . 001 mm ) adhesive cap coatings exhibit sufficient flexibility to survive substantial strain , e . g . during crimping and expanding of a coated stent , without coating damage or spallation ( 3 ) porous cap coatings can be produced , with controlled amount and size of the pores , which allows design flexibility in choice and absorption / release characteristics for the drug impregnated into the coating ( 4 ) the synthesis requires low temperature (˜ 350 ° c .) and short time (& lt ; 1 hour ) of calcination for formation of high quality , highly adhesive cap coating . low temperature calcination of the novel cap coatings on metals permits thermal treatment in an air environment without the risk of metal oxidation and possible property degradation due to microstructural deterioration or phase transformations . it will be clear for the person skilled in the art of sol - gel processing that coating deposition parameters , such as time , the flow rate of the aerosol , temperature of the coating chamber or the concentration of the sol - gel solution can be customized for different implantable medical device materials and applications producing various degree of coverage on the surface . similar manipulation and optimization of process parameters may be applied to other coating methods disclosed , i . e . dip - and spin - coating and electrophoresis , biomimetic coating , electrochemical deposition coating , calcium phosphate cement coating , electrophoretic deposition coating , as well as coating porosity distribution and ratio of the inorganic phase ( cap ) to organic phase ( biodegradable polymer ). these parameters were optimized for the particular cap coatings on the implantable medical devices described in the foregoing examples . it is well known that crystallinity and microporosity of hydroxyapatite directly affects its dissolution rate in body fluids . different heat treatment regimes and temperatures can be adopted to produce various degrees of crystallinity and microporosity to control the degradation of the coating into the body environment . this advantage is of a great importance where drug delivery capabilities are added to the implantable medical device surface coated with sol - gel derived cap . similar deposition process can be applied to coating other metallic surfaces , such as ti substrates or other alloys , such as cobalt - chromium - nickel - molybdenum - iron . a thin uniform thin ha coating is obtained . the results of this experiment provide basic evidence of the feasibility of the as described coating on implantable medical devices composed of non - metallic materials such as polymers . the nature of the process for cap coatings deposition according to the invention is such that it can be easily incorporated into the current production practice of metallic implantable medical devices . the water - based liquid precursors to cap ceramic coatings , simple deposition technique ( e . g . dipping or spin - coating or aerosol deposition or electrophoretic deposition , and others ) and low - temperature heat treatment in air make the process not unlike simple painting - curing operation which can be commercialized with relatively small effort . as will be apparent to those skilled in the art in the light of the foregoing disclosure , many alterations and modifications are possible in the practice of this invention without departing from the scope thereof . accordingly , the scope of the invention is to be construed in accordance with the substance defined by the following claims .

this invention relates to novel calcium phosphate - coated implantable medical devices and processes of making same . the calcium - phosphate coatings are designed to minimize the immune response to the implant and can be used to store and release a medicinally active agent in a controlled manner . such coatings can be applied to any implantable medical devices and are useful for a number of medical procedures including balloon angioplasty in cardiovascular stenting , ureteral stenting and catheterisation . the calcium phosphate coatings can be applied to a substrate as one or more coatings by a sol - gel deposition process , an aerosol - gel deposition process , a biomimetic deposition process , a calcium phosphate cement deposition process , an electro - phoretic deposition process or an electrochemical deposition process . the coating can contain and elude a drug in an engineered manner .

preferred embodiments of the invention are illustrated and described in connection with a stapler for applying staples to an exterior wound or incision across a layer of skin , although the invention is not limited to such a surgical stapler . the embodiment of the stapler illustrated in fig1 - 9 comprises as depicted in fig1 a rear housing portion 10 and a front housing portion 11 . the front housing portion 11 is mounted to the rear housing position for rotation of the front housing portion about its longitudinal axis . the mechanism 12 for actuating the stapler is contained in the rear housing portion 11 . a slide 13 which advances a driver 15 is guided in the front housing portion 10 for longitudinal displacement but is prevented from rotating . the slide 13 comprises a forwardly projecting flexible tongue 14 which also cooperates with the driver 15 , as described more fully below . the driver 15 comprises an elongated rigid strip of material which is displaceable in its longitudinal direction in a channel or duct 16 . the strip has a central recess 17 ( fig4 ) at the forward end of which is disposed a bent - up section 18 having an enlarged head . a leaf spring 19 extends in the channel 16 substantially parallel to the driver 15 . the leaf spring 19 has an inclined surface 20 ( fig2 ) and is provided with a central slot 21 ( fig4 ) closed on all sides which extends forwardly and rearwardly of the region of the inclined surface 20 . the enlarged head of the bent section 18 of the driver 15 protrudes through the slot 21 and is pressed against the upper side of the leaf spring 19 . the forward end of the leaf spring 19 is bent downwardly to form the anvil surface 22 . the rear end of leaf spring 19 is fixed to the front housing portion 11 . when the driver 15 is in its retracted position , as depicted in fig2 the bent section 18 is positioned at the base of the inclined surface 20 . due to the inherent tension in the front region of the leaf spring 19 , the leaf spring positions itself in the channel 16 as depicted in fig2 . since the height of the channel 16 is greater than the height of the anvil 22 , there is a clearance between the anvil 22 in its retracted position and the lower region 16 &# 39 ; at the front of the channel 16 . a staple magazine 26 ( fig1 and 6 ) extends parallel to the channel 16 in the front housing portion 11 . staples 24 are arranged in the magazine standing upright side by side and extending along the feed passage of the magazine parallel to the channel 16 . a helical spring 25 braced against the housing contacts the rearmost staple and urges the rearmost staple and with it the entire stack of staples forward under constant tension . the forward section 26 &# 39 ; of the staple magazine 26 is curved upwardly at an angle of 90 ° and opens into the channel 16 . the staples are urged into the curved section 26 &# 39 ; of the magazine and extend along the arc of the curve as depicted in fig6 with the forwardmost staple 24 &# 39 ; being disposed lying flat in the channel 16 . the lower region 16 &# 39 ; in the forward portion of the channel 16 in which the leaf spring 19 can move vertically is of greater width than the region above it . the height of the wider , lower channel portion 16 &# 39 ; is only slightly greater than the thickness of the staples 24 so that channel portion 16 &# 39 ; forms a guide channel for the advance of the forwardmost staple 24 &# 39 ; and for the driver 15 . this guide channel is defined by the lower guide face 16a , the two upper guide faces 16b , ( fig6 ), and by the lateral guide faces 16c ( fig4 ). the staples 24 , whose undeformed configuration is depicted in broken lines by the staple 24 &# 39 ; in fig5 have arcuate side portions 24a connected via a straight leg region 24b to a central base or crown portion 24c . the straight leg regions 24b extend obliquely outwardly from the base portion to the side portions 24a . the base portion 24c is semicircular with the circumference of the semicircle facing in the direction of the side portions . the base portion is engaged by the anvil surface 22 during forward motion of the staple . in order to insure centering of the staple 24 , the anvil surface 22 is provided with a vertical slot 22 &# 39 ;. in the arcuate section 26 &# 39 ; of the staple magazine 26 , the side portions 24a of adjacent staples 24 are spaced apart while the straight leg regions 24b are in contact with adjacent leg regions due to the difference in radii of the curves for the upper and lower surfaces of the arcuate section 26 &# 39 ;. thus , the force of the spring 25 can be transmitted through the staples in the arcuate section 26 &# 39 ; to the forwardmost staple 24 &# 39 ;. at the opening 27 ( fig5 ) of the magazine 26 into the channel 16 , the underside of the upper guide face 16b is embossed ( not shown ) to hold the forwardmost staple 24 &# 39 ; in a well - defined position . as the driver 15 is advanced from retracted position shown in fig2 ; its front end abuts the forwardmost staple 24 &# 39 ; and pushes it forward in the channel section 16 &# 39 ;. at the same time , the bent section 18 moves along the inclined surface 20 of the leaf spring 19 so that the anvil surface 22 at the forward end of the leaf spring is brought from its retracted position into the operative position shown in fig3 . the staple designated 24 &# 34 ; in fig3 and 4 is now situated between the forward end of driver 15 and the anvil surface 22 in a position in which the tips of the staple side portions protrude slightly forwardly from the instrument . as the driver 15 is advanced further , the staple side portions emerge from the front end of the instrument , with staple 24 &# 34 ; being deformed and closed to the solid line configuration depicted in fig5 in which the base 24c of the staple has been bent flat on the inner side of the anvil surface 22 . to obtain as long a guide path as possible during deformation of staple 24 &# 34 ;, the guide faces 16a , 16b and 16c extend into projections 28 which define the exit gap of channel 16 out of the housing and which protrude slightly beyond the anvil surface 22 . as soon as the driver 15 has carried the forwardmost staple 24 &# 39 ; away from the opening 27 of the magazine into the channel , the opening 27 is closed by the driver so that the next staple cannot be advanced into the channel 16 . the next staple can only be advanced into the channel after the driver 15 has returned to its retracted position where it is clear of the opening 27 . fig7 - 9 illustrate control of the driver 15 by the slide 13 . slide 13 , which is supported to the front housing portion 11 for longitudinal displacement but is prevented from rotating , comprises at its forward end a forwardly projecting , flexible tongue 14 which is vertically springloaded . a laterally projecting guide wing or cam surface 30 is disposed at the end of the tongue 14 and cooperates with a control cam 31 fixed to the housing portion 11 . when the slide 13 is advanced by the actuating mechanism 12 , its front face strikes driver 15 , pushing it in the direction of the tool tip . a bevel formed on wing 30 causes wing 30 to abut on a rearward bevel of the control cam 31 . the tongue 14 then flexes upwardly and wing 30 slides on the upper cam surface 32 . if the slide 13 is retracted before its forward end position is reached corresponding to the operating position of the driver , the wing 30 slides back on to the upper cam surface 32 , which maintains the slide and correspondingly the driver in the advanced position they assumed . only after the slide 13 reaches the position shown in fig8 and the wing 30 has gone beyond the front end of the control cam 31 is the stamping operating completed and staple 24 &# 34 ; closed . as the slide 13 is thereafter being moved back , the rear surface of the wing 30 , which is inclined , contacts the correspondingly inclined forward surface of the control cam 31 . as a result , the tongue 14 is forced downward , and a projection of the tongue 14 enters into the slot 17 of the driver 15 . as the slide 13 is further retracted , the wing 30 is pulled beneath the control cam 31 , and the driver 15 is drawn rearward . referring to fig7 after the wing 30 has passed along the underside of the control cam 31 , the tongue 14 springs upward , releasing the driver 15 at its starting position . until the driver 15 is pulled back to its starting position , it does not clear the opening 27 of the staple magazine 26 into the channel 16 . fig1 depicts an embodiment in which a counting mechanism 33 is secured to the front housing portion 11 . the counting mechanism is stepped by movement of the tongue 14 of the slide 13 . the counting mechanism 33 comprises a hollow cylinder 34 fixed in the housing portion 11 in which is rotatably mounted a cylinder 35 having ratchet teeth 36 disposed about the periphery of the lower end thereof . a projection 37 disposed at the front end of tongue 14 engages the teeth 36 when the wing 30 is raised by the guide cam 31 during a feed movement . in this manner the cylinder 35 is rotated towards the forward end of the instrument by a predetermined angle with each feed movement of the driver 15 . the top of the cylinder 35 is provided with a mark and the periphery of the hollow cylinder 34 is provided with a scale so that the mark indicates on the scale the number of staples 24 remaining in the magazine 26 . at the rear end of the front housing portion 11 is disposed a cylindrical bushing 40 ( fig1 ) in which slide 13 is coaxially mounted . the cylindrical bushing 40 can be removed from the rear housing portion 10 so that the magazine can be loaded with staples . the rear end of the slide 13 is coupled to a part 39 slidably movable along a track 42 in the interior of the rear housing portion 10 . the sliding part 39 includes a sleeve 43 disposed about a shank 44 of the slide 13 which is bounded on both sides by flanges . the sliding part 39 is provided with a rack 45 having teeth or serrations which are engaged by corresponding serrations on a toothed disc segment 46 . the toothed disc segment 46 forms one lever arm of a two - armed lever which pivots about a pivot pin 47 in the housing portion 10 . the other lever arm 48 is engaged by a pin 49 disposed in a transverse slot 50 of a trigger lever 51 . the trigger 51 is guided in a recess 52 of the handle 53 extending approximately parallel to channel 16 , and is urged outwardly of the handle by a spring 54 . trigger 51 is dimensioned so that it can be actuated with the index finger when the handle 53 is gripped . the trigger , upon being pushed into the handle 53 , causes the lever 46 , 48 to be pivoted about the pivot pin 47 so that the sliding part 39 is advanced forwardly , and with it slide 13 . near the end position of the lever 46 , 48 where it extends almost at right angles with the slide 13 , leverage is the greatest , and corresponds to the stamping action of the driver . thus , for a constant actuating force , the maximum force applied to the driver occurs during stamping . an actuating mechanism 12 &# 39 ; similar to mechanism 12 of fig1 is illustrated in fig1 and 12 . fig1 depicts the retracted position of the slide 13 and fig1 its advanced position . spring 54 urges the trigger 51 out of the handle 53 and at the same time brings the sliding part 39 , and with it the slide 13 , into the retracted position . in the embodiment of fig1 the transverse slot 50 of the trigger 51 has an angular shape , while in the embodiment of fig1 and 12 , the transverse slot 50 is straight . certain changes and modifications of the embodiments of the invention disclosed herein will be readily apparent to those skilled in the art . it is the applicants &# 39 ; intention to cover by their claims all those changes and modifications which could be made to the embodiments of the invention herein chosen for the purpose of disclosure without department from the spirit and scope of the invention .

a stapler , particularly for suturing skin wounds or incisions , is disclosed which comprises a channel in which a driver is advanced by a slide in the direction of an anvil surface . a staple magazine which extends substantially parallel with the driver includes a curved section which opens into the channel to deliver staples into the channel for engagement by the driver . during forward displacement of the driver , a projection on the driver presses a leaf spring to which the anvil surface is connected . the anvil surface at the forward end of the leaf spring is thereby brought into its operating position and is automatically moved back into its retracted position upon release of the spring after the driver is retracted . the curved section in the staple magazine enables the stapler to have a slim profile which does not obscure the working area during a stapling operation . after completion of a stapling operation , the anvil surface is automatically retracted from a closed , implanted staple .

embodiments of the present invention provide ngcs with integrated spiral structured porous sheets decorated with surface channels and electrospun fibers . such ngcs provide superior mechanical strength compared to ngcs in the prior art , along with integrated multiple channels , stable aligned fibrous layers , good inter - cell communication , and high surface / volume ratios within the ngcs . chambers at the distal and proximal ends of the ngc provide additional space for fitting nerve stumps in order to reduce the tension at the suture line between the ngc and the nerve stump . a dense outer fibrous tube on the outside of the spiral structured porous sheet can prevent the infiltration of scar tissue while the regeneration process takes place . one embodiment of the ngc of the present invention comprises a three - dimensional ( 3 - d ) spiral structured porous sheet having two chambers at the ends thereof . the spiral structure includes a highly porous polycaprolactone ( pcl ) sheet , which may be formed as a spiral - wound sheet using known methods and decorated with surface channels on a surface of the spiral wound sheet , coated with a thin layer of aligned electrospun fibers on the surface channels , and a dense randomly - oriented fibrous tube on the outside of the ngc . other bioresorbable materials known for use in the biomedical arts may be used in place of pcl for the sheet and fibers ( e . g ., collagen / pcl blends for the fibers ). other embodiments of the present invention provide a process for fabricating an implantable ngc , such as the embodiment of an ngc described above , which can be used as a medical device for facilitating the repair and regeneration of nerve tissues . several features of ngcs according to embodiments of the present invention are discussed herein below . 1 . three - dimensional ( 3 - d ) integrated spiral structured porous sheet with proximal and distal reserved chambers collagen tubes , which have been approved by the fda , lack sufficient mechanical strength to support nerve regeneration . as for multi - channel ngcs , the major drawback is that cells / axons in each channel do not interact well with those in the other channels , which adversely affects nerve regeneration and would affect nerve function recovery even if the nerve gap were bridged . in comparison , the integrated spiral structure makes the ngc of the present invention superior to those in the prior art in that mechanical properties are greatly improved and favorable for inter - cellular interaction and neural myelination . this is important for nerve regeneration because of the time required for nerve regeneration to bridge large nerve gaps . further , a ngc should have enough mechanical strength to provide structural support to the nerve during regeneration . also , the proximal and distal chambers in the ends of the ngc provide an optimal initial environment for nerve ingrowth . these chambers can prevent stress from accruing when the nerve tissue is sutured with the conduit in an end - to - end fashion . moreover , the increased surface / volume ratio and the highly porous intermediate layers of the pcl sheet are preferred for cell attachment and nutrient transportation during nerve regeneration . 2 . decorated surface channels on the spiral porous sheet with additional electrospun aligned fibers and and an outer fibrous tube electrospinning is an approach for polymer biomaterial processing that provides an opportunity to control morphology , porosity and composition of an ngc using relatively unsophisticated equipment . unlike conventional fiber spinning processes that produce fibers with diameters in the micrometer range , electrospinning is capable of producing fibers in the nanometer diameter range , which are typically deposited in the form of nonwoven fabrics . nanofibers provide a connection between the nanoscale and the macroscale world , since , although their diameters are in the nanometer range , the fibers are very long , sometimes having lengths of the order of kilometers . a major problem of all hollow tubes is misdirection of cellular migration : since transected axons produce axon sprouts proceeding in a distal direction , a neuroma is always formed which consists of minifascicles proceeding in an abnormal manner , proliferating schwann cells ( scs ), fibroblasts and capillaries . if there is a directional factor of any kind ( e . g ., an artificial nerve tube which usually provides no endoneurial structure ), the neuroma proceeds in the desired direction . this phenomenon has been called “ neuromateous neurotization ”. in consequence , only a few dispersed axons are able to enter the right fascicle and endoneurial tube in the distal nerve stump once they have reached the end of the conduit in the interior of the ngc . one successful tissue engineering strategy for nerve repair is to create aligned features on the conduit to provide guidance for cell migration and directional axonal regeneration across the glial scar and lesion site in both central nervous system and peripheral nervous system injuries . such features may include aligned surface channels and electrospun fiber - based conduits for nerve repair , according to embodiments of the present invention . consequently , the construction of a spiral structure conduit with highly aligned surface channels and nano - fibers is very helpful for nerve proliferation and neurite extension . meanwhile , the intricate aligned structure can also influence the growth and distribution of seeded scs , which further directs the longitudinal extension of the neural axons . further , there is a wide range of polymers available that are suitable for deposition on the spiral sheet to meet the individualized specifications for the ngc ( e . g ., collagen / pcl copolymer nanofibers , rather than pure pcl sheets ). fibers spun along the outside of the ngc not only assist in stabilizing the spiral structure , but also inhibit infiltration of scar tissue through the inter - connective pores . by increasing the mechanical strength of the ngc , the risk of structural failure can be minimized , promoting more uniform and natural regeneration of nerve tissue . in order to solve the conflict between optimizing the mechanical properties of the ngc and maximizing its length , many techniques may be used to reinforce the ngc . in a method according to an embodiment of the present invention , a spiral conduit ( e . g ., a spiral structured porous sheet ) is placed onto a rotator and a nanofiber is spun in random orientations along the spiral structure to form an outer fibrous tube . the thickness of the outer fibrous tube can be controlled . this dense layer of randomly - oriented fibers deposited on the outside of the spiral conduit can improve the mechanical properties of the entire structure , and meanwhile provide a stable structural support during nerve regeneration . in a method according to an embodiment of the present invention , depositing the outside layer of fibers on the spiral conduit is the final and separate step of fabricating the ngc , so it is practical to modify the polymers used to form the fibers before the electrospinning step . the outer fibrous tube can be made from polymers that are different from that of the spiral sheet or the aligned fibers . in another aspect , the process of the present invention is tunable in that the sizes of the spiral conduit are controllable , and both the length and the outside diameter are dependent on the size of the spiral - wound sheet . therefore , in order to fabricate a spiral conduit with a particular size , ( e . g ., a length larger than 15 mm , which is the maximum length of nerve regeneration achieved with silicone tubes in rats ), it is only necessary to cut a polymer sheet to the appropriate size . fig1 is a schematic illustration in cutaway view of a nerve guidance conduit ( ngc ) 10 according to an embodiment of the present invention bridging the stumps 12 , 14 of damaged nerve 16 . the stumps 12 , 14 are received in reserved chambers 18 , 20 at the proximal and distal ends 22 , 24 of the ngc 10 , and held in place with sutures 26 , 28 , or by other means known in the art . the reserved chambers 18 , 20 allow the nerve stumps 12 , 14 to be placed in the ngc 10 and sutured without tension by housing the nerve stumps 12 , 14 in place with an optimal grip . fig2 is a schematic cross - sectional view of the ngc 10 showing that the ngc 10 includes an outer fibrous tube 30 surrounding one or more spiral wound sheets 32 the fibrous tube 30 includes a dense structure of randomly oriented polymer fibers ( not shown ). the spiral wound sheets 32 define a lumen 34 inside the ngc 10 . the lumen 34 is bounded by an inner surface 36 of the spiral wound sheets 32 . the ngc 10 further includes an integrated guidance spiral 38 having a plurality of surface channels 40 . the guidance spiral 38 is are composed of multiple layers ( e . g ., layers 42 , 44 ), and together define a spiral guidance channel 46 within the lumen 34 . in some embodiments of the present invention , the surface channels 40 are arranged such that they are substantially parallel to each other and to a longitudinal axis ( not shown ) of the ngc 10 . the layers 42 , 44 may be extensions of the spiral - wound sheets 32 , or may be formed separately therefrom , then integrated with the spiral - wound sheets 32 . the plurality of surface channels 40 increases the surface area of the guidance spiral 38 that is available for cell migration and may reduce the length of time needed for nerve regeneration . additionally , the integrated layers 42 , 44 may reduce the wear and tear that can occur in ngcs known in the art . such wear and tear is often observed with single lumen tubular ngcs . in some embodiments of the present invention , a highly aligned orientation of electrospun nanofibers ( not shown ) are provided as coats on the surface channels 40 , and on both layers 42 , 44 of the spiral sheet 38 , and dense randomly - oriented fibers are provided on an outer surface 48 of the ngc 10 , which greatly improves the mechanical properties of the ngc 10 , as discussed above . in some embodiments , the aligned fibers are substantially parallel to each other . in some embodiments , the aligned fibers are substantially parallel to a longitudinal axis of the ngc 10 . the presence of aligned fibers ensures that all areas of the regenerating axon will come into contact with aligned fibers . the ngc 10 is tunable such that its size can be varied in a controlled fashion depending on how it is to be used . the length and the outer diameter of the ngc 10 are dependent on the size of guidance spiral 38 . an ngc 10 according to the present invention may have any length , thus enabling it to be used to repair long gaps in the axon for the repair or regeneration of peripheral nerves . fig3 and 4 are scanning electromicrograph ( sem ) images a first side and a second side opposite the first side of a portion of a porous polymeric sheet 50 of a type that may be used to fabricate the spiral - wound sheets 32 or guidance spiral 38 of an ngc of the same type as ngc 10 , before the application of electrospun nanofibers . interconnected pores ( e . g ., pores 52 ) are present throughout the polymeric sheet 50 . fig5 is an sem image of a porous polymeric sheet 54 of the same type as polymeric sheet 50 , showing aligned nanofibers 56 that have been deposited on the polymeric sheet 54 by electrospinning . fig6 is an sem image of a porous polymeric sheet 58 of the same type as polymeric sheets 50 , 54 showing randomly - distributed nanofibers 60 that have been deposited on the polymeric sheet 58 by electrospinning . fig7 - 9 are stereomicroscopic images of an ngc 62 according to an embodiment of the present invention . ngc 62 is of the same general type as the ngc 10 discussed with respect to fig1 and 2 . fig7 is an image of the intact ngc 62 showing its outer fibrous tube 64 . fig8 is an image of the interior of the ngc 62 after it has been cut lengthwise , showing an interior surface 66 of the outer fibrous tube 64 , the guidance spiral 66 , and the reserved chambers 68 , 70 . fig9 is an end view of the ngc 62 showing the outer spiral wall 64 , the guidance spiral 66 and the channels 72 of the guidance spiral 66 . fig1 is a sem image of a portion of polymer sheet 74 , which is of a type for making an ngc according to an embodiment of the present invention , showing the substantially parallel alignment of channels 76 , which are separated by ridges 78 . in a method of fabricating an ngc according to an embodiment of the present invention , a polycaprolactone ( pcl ) sheet was fabricated using a combination of the solvent evaporation method and the salt - leaching method . an 8 % ( w / v ) pcl solution was poured onto a glass petri dish , and acupuncture needles having a diameter of 150 μm were placed on top of the pcl solution to form multi - channels having widths of about 180 μm . the dish was moved to a hood to let it air dry . after an hour , the resulting pcl sheet was immersed into deionized water so that the salt was dissolved , producing pores in the pcl sheet . the needles were also removed , having formed multi - channels on the pcl sheet with widths of about 180 μm . after 30 minutes , the pcl sheet was taken out and dried on a paper towel . subsequently , 2 hours later , the fully dried pcl sheet was cut into a rectangular shape having dimensions of about 12 mm by 10 . 5 mm to bridge a 10 mm nerve gap in an animal study . referring to fig1 , in an exemplary embodiment of the method , the cut pcl sheet 80 had opposite longer edges 82 , 84 ( i . e ., the 12 mm edges ), and opposite shorter edges 86 , 88 ( i . e ., the 10 . 5 mm edges ). it may be noted that the channels 90 are substantially parallel to the longer edges 82 , 84 . two rectangular areas 92 , 94 were cut out from the opposite corners 96 , 98 of the edge 82 , such that edge 82 was then shorter than edge 84 . pcl aligned nanofibers were spun on the cut pcl sheet 80 using a conductible rotation disk method known in the art . a 16 % ( w / v ) solution of pcl in 1 , 1 , 1 , 3 , 3 , 3 hexafluoroisopropanol ( hfip ) ( oakwood products , inc ) was prepared for electrospinning . aligned fibers were deposited on the 12 mm × 10 . 5 mm pcl sheet longitudinally on the edge of the rotating disk such that the fibers were substantially parallel to channels 90 . the fibers were deposited such that they would be substantially longer than the cut pcl sheet 80 . the sheet was carefully removed from the disk to ensure the fibers deposited remained aligned . the excess lengths of fiber ( i . e ., the portions of the fibers that extended beyond the edges of the cut pcl sheet 80 were collected and folded onto the back of the cut pcl sheet 80 . turning back to fig1 , the cut pcl sheet 80 with the aligned nanofibers thereon was then wound in a spiral fashion from the edge 82 to the edge 84 , such that the edge 82 was in the interior of the resulting spiral ngc and the channels 90 were substantially parallel to a longitudinal axis of the spiral ngc . in the spiral ngc , the cutaway areas 92 , 94 become reserved chambers ( e . g . reserved chambers 68 , 70 of spiral ngc 64 of fig7 - 9 , or reserved chambers 18 , 20 of spiral ngc 10 of fig1 ). random nanofibers were then spun onto the outside of the spiral ngc to form an outer fibrous tube on the spiral ngc . the thickness of the outer fibrous tube was approximately 150 μm . the outer fibrous tube is intended to secure the entire spiral structure , enhance the mechanical strength , and prevent tissue infiltration during nerve regeneration . the resulting spiral ngc with its outer fibrous tube was 1 . 8 mm in diameter and 12 mm in length , suitable for bridging a 10 mm nerve gap . fig1 is a plot of stress versus strain for several ngcs fabricated according to a method of the present invention : an outer fiber tube comprising a dense layer of randomly - oriented nanofibers ; the outer fiber tube with a spiral sheet therein , and the outer fiber tube with the spiral sheet and aligned nanofibers (“ af ”). the following tensile properties were measured : young &# 39 ; s modulus , percent elongation to failure , and tensile strength of the different ngcs . the young &# 39 ; s modulus , calculated through the stress - strain curve shown fig1 , ranged between 0 . 262 - 0 . 7625 mpa . all three of the ngcs yielded a young &# 39 ; s modulus that can stand force stretching and be applicable for in vivo use . the values reported for the outer fibrous tube and the other ngcs all in a useful range for use in nerve regeneration and repair . high tensile strength will provide a mechanically strong ngc that can be sutured well during coaptation of the nerve stump and ngc , and preserve the suture after surgery . the measured physical properties of the ngcs of fig1 are summarized in table 1 , below . the measured porosity values for the outer fibrous tube ( hereinafter , ngc - t ), outer fibrous tube + spiral ( hereinafter , ngc - t - s ), and outer fibrous tube + spiral + af ( hereinafter , ngc - t - s - af ) were respectively 71 . 98 ± 1 . 22 %, 75 . 01 ± 2 . 69 %, and 78 . 41 ± 3 . 64 %. the differences in porosities for these three types of ngcs are not statistically significant ( p & lt ; 0 . 05 ). schwann cells were adopted as the model for evaluation of cellular response on the fiber - based spiral ngcs . at day 4 , ngc - t - s - af showed significantly greater cell proliferation than ngc - t and ngc - t - s . the cell numbers for each type of ngc are shown in fig1 . the degrees of cell proliferation for the ngc - t and ngc - t - s are significantly lower ( p & lt ; 0 . 05 ) than for the ngc - t - s - af . the ngcs were tested in a 10 mm sprague dawley ( sd ) rat sciatic nerve defect to evaluate the effect of nanofibers on peripheral nerve regeneration through porous spiral ngcs . the sciatic nerve of each rat was cut , then bridged with one of the ngcs . one group received an autograft rather than a ngc . one group received no grafts . all rats were in good condition during the survival weeks . there were no obvious signs of systemic or regional inflammation and surgical complications after implantation the recovery of motor function was assessed based on the walking track evaluation referring to fig1 , normal sciatic functional index ( sfi ) value of − 9 . 4 ± 1 . 4 was measured from all healthy rats ( n = 30 ) before surgery . all experimental animals had decreased sfi of values between − 85 . 6 and − 94 . 5 ( n = 30 ) by week 2 after surgery . during the initial 4 weeks , there was no significant improvement in any of the groups . at 6 weeks after surgery , the overall sfi reached the levels between − 72 . 2 and − 91 . 7 , which was equivalent to an improvement of 2 . 8 - 13 . 4 index points from week 2 . each group &# 39 ; s 6 - week sfi value was recorded as follows : autograft (− 72 . 2 ± 6 . 6 ), t - s - af (− 81 . 5 ± 3 . 2 ), t - s (− 88 . 4 ± 4 . 9 ), and t (− 91 . 7 ± 4 . 2 ). the autograft sfi revealed a significant difference ( p & lt ; 0 . 05 ) as compared to the t - s and t groups . the sfi in the t - s - af group was significantly higher than for the t groups ( p & lt ; 0 . 05 ). functional recovery was further evaluated with electrophysiological assessment to determine whether functional recovery occurred through the ngcs . six weeks post - surgery , compound muscle action potentials ( cmap ) were evoked by stimulation at the surgical limbs and recorded from gastrocnemius muscle following by measurements of amplitude and nerve conduction velocity ( ncv ). signals were absent and no muscle contractions were observed in the non - grafted group . referring to fig1 , for the amplitude measurements , each group &# 39 ; s value was recorded as follows : autograft ( 5 . 25 ± 1 . 51 mv ), t - s - af ( 4 . 96 ± 1 . 58 mv ), t - s ( 3 . 6 ± 1 . 39 mv ), and t ( 2 . 0 ± 0 . 64 my ). significant differences in amplitude were observed in the t group as compared to the autograft and t - s - af groups ( p & lt ; 0 . 05 ). however , the difference between the autograft , t - s - af , and t - s groups ( p & gt ; 0 . 05 ) was not statistically significant . similar results were found in ncv measurement : autograft ( 31 . 57 ± 4 . 13 m / s ), t - s - af ( 26 . 47 ± 6 . 87 m / s ), t - s ( 18 . 28 ± 4 . 16 m / s ), and t ( 13 . 3 ± 5 . 65 m / s ) ( see fig1 ). significant differences in ncv were observed in the autograft group as compared to the t - s and t groups ( p & lt ; 0 . 05 ). the ncv result in the t group also showed a significant difference as compared to autograft and t - s - af groups ( p & lt ; 0 . 05 ). however , there were no significant differences when the ncv values of the autograft group were compared to those of the t - s - af group , which may indicate that nanofibers can accelerate the level of muscle reinnervation as well as autograft . after 6 weeks post - surgery , the distal nerve segment from each group was explored and carefully isolated from the surrounding tissues . a pinch reflex test was performed distally . a reflex movement of the back muscles indicates that the sensory fibers are positively regenerated through the ngcs , while no movement was considered as lack of sensory fibers in the ngcs . the results are presented in table 2 , below . further histological evaluations of nerve regeneration behavior with ngcs were investigated under a light microscope . the results clearly demonstrated the potential of the ngcs of the present invention to house a large number of supportive cells , both with and without nanofibers to enhance the surface area of the channel . the ngcs possessed durable mechanical strength to support the entire regeneration process . low magnifications of micrographs showed that neural tissues , including myelinated axons and myelin sheath , were all successfully presented among the groups . angiogenesis occurred through which new blood vessels were formed during the nerve regeneration process . normal axons were nearly all surrounded by uniform thicknesses of myelin sheaths and presented large fiber diameters . nevertheless , the studied groups presented premature morphologies ( i . e ., diverse nerve fiber sizes and thinner myelin sheaths ). quantitative analysis of the total occupied neural tissue coverage in the ngcs compared to those of normal rat nerves ( 70 . 57 ± 3 . 81 %) further confirmed the above findings . referring to fig1 , each group &# 39 ; s value was recorded as follow : autograft ( 29 . 29 ± 4 . 61 %), t - s - af ( 26 . 52 ± 3 . 77 %), t - s ( 17 . 37 ± 2 . 97 %), and t ( 5 . 88 ± 1 . 43 %). no significant differences were found among autograft and t - s - af groups . however , the area occupied by neural tissue in t - s group showed significantly lower values than the autograft , and t - s - af groups . high significance was observed in the t group as compared to the other groups ( p & lt ; 0 . 01 ). finally , it should be noted that the cross - sectional micrograph of t group was covered with a large white area . that implied the single lumen repair limited the nerve regeneration . when severe nerve injury occurs , the muscle is denervated and the balance of muscle metabolism could be shifted from protein synthesis toward protein degradation . as a consequence , the target muscle presents a decreased muscle cell size , muscle weight loss , hyperplasia of connective tissues , and new blood vessel formation . to evaluate the reinnervation of the gastrocnemius muscle , masson trichrome staining was applied to the section followed by measurements of muscle weight ratio , diameter of muscle fibers , and muscle fiber coverage per cross section . referring to fig1 , for comparisons of muscle weight ratio , each group &# 39 ; s value was recorded as follows : autograft ( 39 . 73 ± 4 . 19 %), t - s - af ( 25 . 64 ± 3 . 01 %), t - s ( 22 . 31 ± 2 . 18 %), and t ( 19 . 2 ± 2 . 03 %). the muscle weight ratio of the autograft group was greater than that of the other groups by a statistically significant amount ( p & lt ; 0 . 05 ). however , there were no significant differences between the t - s - af and t - s groups ( p & gt ; 0 . 05 ). the t group revealed a significant lower ratio than the t - s - af group . referring to fig1 , for comparisons of muscle fiber diameter , each group &# 39 ; s value was recorded as follows : autograft ( 34 . 62 ± 1 . 05 μm ), t - s - af ( 31 . 81 ± 2 . 18 μm ), t - s ( 25 . 5 ± 6 μm ), and t ( 21 . 56 ± 2 . 98 μm ). although the autograft group showed a significant difference from the t - s and t groups , it was not significantly higher than the t - s - af group . also , there were no significant differences between the t - s and t groups ( p & gt ; 0 . 05 ). further findings showed that the value for the t group was significantly lower than that for the autograft , and t - s - af groups . referring to fig2 , for comparisons of muscle fiber coverage , each group &# 39 ; s value was recorded as follows : autograft ( 96 . 84 ± 4 . 1 %), t - s - af ( 93 . 72 ± 4 . 63 %), t - s ( 86 . 99 ± 10 . 31 %), and t ( 58 . 42 ± 4 . 69 %). there were no significant differences between the values for the autograft , t - s - af , and t - s groups ( p & gt ; 0 . 05 ); however , they were all significantly greater than the value for the t group ( p & lt ; 0 . 05 ). from qualitative analyses and histological observations discussed above , spiral ngcs of the present invention , with or without nanofibers , revealed the potential to prevent muscle atrophy as well as the effect of autograft . both the surface channels and the aligned fibers provide good topographical cues for nerve regeneration , and thus allow muscle reinnervation faster than single lumen ngcs , thus suggesting that the surface channels and nanofibers further assisted ngc structures in promoting nerve regeneration . it should be understood that the embodiments described herein are merely exemplary in nature and that a person skilled in the art may make many variations and modifications thereto without departing from the scope of the present invention . all such variations and modifications , including those discussed above , are intended to be included within the scope of the invention , as defined by the appended claims .

a nerve guidance conduit includes a spiral structured porous sheet decorated with channels on its surface and electrospun nanofibers in a parallel alignment with the channels and an outer tubular structure including randomly - oriented nanofibers . such a structure provides augmented surface areas for providing directional guidance and augmented surfaces for enhancing and peripheral nerve regeneration . the structure also has the mechanical and nutrient transport requirements required over long regeneration periods . to prepare a nerve guidance conduit , porous polymer sheet is prepared by a solvent casting method while using a template of thin rods to form parallel channels on a surface of the sheet . aligned nanofibers are deposited on the sheet parallel to the channels . the polymer sheet is then wound to form a spiral structure . a dense layer of randomly - oriented nanofibers may be deposited on the outside of the spiral .

referring now to the drawings , and particularly to fig1 and 2 , a portion of the back end of a furniture seat base is illustrated generally at 10 . the seat base 10 comprises spring band assemblies 15 , only one of which is shown , extending in parallel relationship between the front rail ( not shown ) and back rail 16 of the base frame . each assembly 15 includes a normally arced sinuous spring band 20 of standard loop size ; i . e ., a seven - eighths ( 2 / 3 ) inch interval between linear segments 25 and semi - circular segments 26 of the band . each band 20 is connected to the back frame rail 16 by a first form of rail connector 30 embodying features of the invention . the rail connector 30 is fabricated of eleven ( 11 ) gauge wire , similar to standard helicals . it comprises a section 35 of three coils tightly wound on an axis transverse to that of the band 20 and the axis of expansion and contraction of the connector 30 . extending from the coil section 35 , at their uppermost extremity , tangent to the arc of the coils and in opposite directions , are a rail - attachment leg 38 and a spring - attachment leg 39 . the rail - attachment leg 38 terminates in a transversely disposed anchor section 40 which seats in a conventional &# 34 ; g &# 34 ; clip 41 , while the spring - attachment leg 39 seats on and grips the spring band 20 . the spring attachment leg 39 is inclined slightly upwardly from the horizontal , in contrast to the rail - attachment leg 38 , and includes an upwardly formed shoulder 45 and a terminal hook 46 . the shoulder is formed approximately mid - way between the hook 46 and tangency with the coil 35 , seven - eighths ( 2 / 3 ) inches each way in the case where the band 20 is regular sinuous . as seen best in fig1 the downwardly opening hook 46 is designed to seat over the penultimate linear segment 25b in the spring band 20 , while the ultimate linear segment 25a seats against the shoulder 45 . the result is to lock the end of the band 20 and the connector 30 together . in operation , the attachment - arm 39 reaching up into the band 20 sets up a torsioning effect in the back of the band . the arm 39 is spring loaded upwardly by the strength of the coil section 35 and produces dynamic uplift . at the same time the coil section 35 permits of longitudinal expansion - contraction of the connector 30 . the coil section 35 and rail - attachment leg 38 extending outwardly of the band 20 end amplify the leverage induced torque . in an alternative construction of the first form of the invention , as seen in fig3 the rail connector 130 is attached to the rail 116 through a gang bore 142 . the rail - attachment leg 138 of the connector has a shorter anchor section 140 which can pass through the bore 142 from front to back of the rail 116 and then seats against the back of the rail to lock the connector 130 to the rail . the spring - attachment leg 139 in this form of the connector is much shorter and has an upwardly formed hook 146 at its inner end . the hook 146 is so formed that when it seats upwardly , onto the ultimate linear segment 125a of the spring band 120 , it cannot slip off during seat base operation . the connector 130 provides both dynamic uplift and resilient expansion - contraction at the band end . it does not induce torsion or leverage amplification . the connector 130 can also be connected to the ultimate linear segment 125a of the band 120 by a conventional vle clip , as seen at 150 in fig4 . as such , the single spring attachment leg 139 obtains a wider purchase area on the band 120 end . the effect is to enhance lateral stability of the spring band assembly . turning now to fig5 a modified coil section for a connector otherwise identical to that hereinbefore discussed is illustrated at 235 . as illustrated , the coil section 235 is tightly wound in five ( 5 ) coils on an axis longitudinally aligned with the sinuous spring band span ( not shown ). this form of the connector 130 produces the same salutary effects , the dynamic uplift being produced by a torquing expansion - contraction of the coil section 235 in contrast to the loop compression - expansion of the coil section 35 , however . fig6 and 7 illustrate a portion of a furniture seat base 310 comprising spring band assemblies 315 ( only one shown ) in which a second form of spring band 320 connector is illustrated at 330 . the connector 330 uses a cantilever principle to provide dynamic uplift to the band 320 at the back rail 316 . the rail connector 330 is fabricated of spring steel wire of relatively heavy gauge ; i . e ., eight ( 8 ) gauge or heavier . as best illustrated in fig7 it includes a pair of identical connector arms 331 extending parallel to each other between the rail 316 and the band 320 . as seen once again in fig6 each connector arm 331 includes a generally v - shaped body 335 made up of a rail - attachment leg 338 and a spring - attachment leg 339 . the legs 338 are vertically oriented and preferably four ( 4 ) inches long . the legs 338 are joined at their upper ends by a base leg 340 which seats in a conventional eks clip 341 stapled to the top of the rail 316 . curving upwardly and inwardly from the lower end of each rail - attachment leg 338 is a corresponding spring - attachment leg 339 . the spring - attachment legs 339 are approximately eight ( 8 ) inches long . formed on the free ends of the legs 339 are attachment hooks 346 identical to the hooks 146 hereinbefore discussed . the connector 330 is a variation of the second form of the invention wherein the hooks 346 receive and seat on the ultimate linear segment 325a of the spring band 320 . in operation the legs 338 are braced against the rail 316 with the spring - attachment legs 339 extending inwardly and upwardly therefrom to the hooks 346 . in unloaded position the hooks are disposed approximately one ( 1 ) inch above the level of the eks clip 341 . the connector 330 thus is effective to dynamically urge the spring band 320 end upwardly when a subject is seated . at the same time longitudinal resilient expansion - contraction can and does take place in the connector 330 , enhancing seat base softness . fig8 illustrates a sinuous spring band assembly 415 which incorporates a connector 430 identical to the connector 330 hereinbefore discussed . in the spring band assembly 415 the connector hooks 446 are seated on a linear segment 425f of the band 420 which is sixth from the end of the band ; i . e ., the ultimate linear segment 425a . the linear segment 425a is connected to the rail by a swing anchor connector clip 460 such as illustrated in fig1 of the aforementioned u . s . pat . no . 3 , 790 , 149 . the base of the clip 460 is seated , together with the base leg 440 of the connector 430 , in the conventional eks clip stapled to the top of the rail 416 . the spring band 420 immediately inwardly of its ultimate linear segment 425a , at the penultimate linear segment , is bent upwardly for the length of one semi - circular band segment 426a and then bent back into the normal arc of the band . this creates a torsion inducing moment arm configuration in the end of the band as illustrated at fig1 in the aforementioned u . s . pat . no . 3 , 525 , 514 . in operation of this spring band assembly 415 the connector 430 performs the same functions as previously ascribed to the connector 330 . further , however , its dynamic uplift is effected inwardly of the band end . this uplift , coupled with the torsion inducing band 420 configuration and the articulate connection provided by the clip 460 produces a highly sophisticated and luxurious seat base . fig9 illustrates a sinuous spring band assembly 515 which also incorporates a connector 530 identical to the connector 330 hereinbefore discussed . in the assembly 515 the sinuous band 520 is a de - arced band , however ; i . e ., it has very little inherent upward resilience . in this assembly the connector 530 pre - loads the band 520 upwardly at the fourth linear segment 525d from the ultimate linear segment 525a . the ultimate linear segment 525a is seated in the eks clip 540 on the rail 516 , together with the base leg 540 of the connector 530 . the connector leg 539 thus preloads the band 520 upwardly with the seat base 10 in its relaxed state as a subject is seated and rises , the connector provides a dynamic uplift which would otherwise not be present . all of the connectors hereinbefore discussed are also used to connect other forms of seat base support means to the frame rails . as will readily be understood , wire grids such as manufactured under the trademark perma - mesh by flexolators , inc ., chord - rubber webbing such as manufactured by the pirelli , s . p . a ., of italy , and flat steel bands , for example , do not have stored upward resilience in the sense that arced sinuous spring bands do . when connected to the back frame rail by connectors embodying the inventions disclosed herein , however , they are provided with a dynamic uplift adjacent the back rail . in this sense they are similar to a de - arced sinuous spring band . while several embodiments described herein are at present considered to be preferred , it is understood that various modifications and improvements may be made therein , and it is intended to cover in the appended claims all such modification and improvements as fall within the true spirit and scope of the invention .

a rail connector and improvement in seat base support assembly . the connector takes two basic forms . in the first a pre - stressed , close wound coil , disposed either transversely or longitudinally of the connector , is effective to continuously bias the seat base support means upwardly . in the second a cantilevered , curved spring arm serves the same purpose . the connector may be configured to reach into the body of a sinuous spring band , for example , and define a torque arm in the band , at the back rail . all forms are applicable to wire mesh , chord rubber webbing , flat steel bands and sinuous , both arced and dearced .

exemplary embodiments of the presently disclosed damage resistant anvil assembly will now be described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views . in this description , the term “ proximal ” is used generally to refer to that portion of the stapler that is closer to a clinician , while the term “ distal ” is used generally to refer to that portion of the stapler that is farther from the clinician . in addition , the term “ endoscopic ” is used generally to refer to procedures performed through a small incision or a cannula inserted into a patient &# 39 ; s body including endoscopic , laparoscopic , and arthroscopic procedures . finally , the term clinician is used generally to refer to medical personnel including doctors , nurses , and support personnel . the presently disclosed anvil assembly includes an anvil head assembly , an anvil shaft , and a stabilizing collet . in embodiments , the stabilizing collet may be formed of a substantially rigid material . alternately , other materials of construction that provide support to the anvil shaft are envisioned . the anvil shaft includes a plurality of flexible legs that flex outwardly in response to insertion of a trocar of a surgical stapling device into the anvil shaft to releasably couple the anvil shaft to the trocar . the collet is received within a longitudinal bore defined by the flexible legs of the anvil shaft at a location to support the flexible legs and minimize the likelihood of damage to the anvil shaft caused by engagement of the anvil shaft with a grasper . the collet is also positioned in a location not to interfere with flexing of the legs during coupling of the anvil shaft to the trocar of the stapling device . fig1 illustrates a manually powered surgical stapler 10 including a stapling device 12 supporting an exemplary embodiment of anvil assembly 100 . the stapling device 12 includes a handle assembly 14 , a body portion 16 that extends distally from the handle portion 14 , and a shell assembly 18 that supports a staple cartridge 20 . the staple cartridge 20 supports a plurality of staples ( not shown ) that are arranged in an annular configuration within the shell assembly 18 . the stapling device 12 also includes a trocar 22 that extends from the distal end of the body portion 16 through the shell assembly 18 . the trocar 22 is configured to releasably engage the anvil assembly 100 as described in further detail below . for a more detailed description of a suitable stapling device , see u . s . pat . nos . 7 , 234 , 624 , 7 , 364 , 060 and 7 , 857 , 187 (“ the incorporated patents ”) which are incorporated herein by reference in their entirety . referring also to fig2 - 4 , the anvil assembly 100 includes an anvil head assembly 102 and an anvil shaft 104 . although not specifically described in this application , the anvil head assembly 102 can be pivotally or fixedly attached to the anvil shaft 104 . examples of pivotally attached anvil head assemblies are described in the incorporated patents . the anvil head assembly 102 includes a housing 106 that supports an anvil plate 108 ( fig2 ) and a cut ring assembly 110 . the housing 106 has a smoothly curved distal surface 112 that facilitates atraumatic entry of the anvil assembly 100 into and through a body orifice or lumen . a proximal side of the housing 106 defines a cavity ( not shown ) that is configured to receive the anvil plate 108 and the cut ring assembly 110 . for a more detailed description of the components of the anvil head assembly 102 , see the incorporated patents . the anvil shaft 104 includes a longitudinal body portion 116 that includes a tubular portion 118 and a plurality of flexible legs 120 that extend proximally from the tubular portion 118 . each of the flexible legs 120 has a semi - cylindrical configuration such that the legs 120 cooperate to define a longitudinal bore 122 ( fig3 ) that is dimensioned to receive the trocar 22 of the stapling device 12 ( fig1 ) when the anvil assembly 100 is secured to the stapling device 12 . the bore 122 extends from the proximal end of the flexible legs 120 at least partially into the tubular portion 118 of the anvil shaft 104 . in embodiments , the anvil shaft 104 may include a plurality of splines 126 positioned about the anvil shaft 104 . as is known in the art , the splines 126 mate with recesses ( not shown ) defined within the shell assembly 16 fig2 ) of the surgical stapling device 12 to properly orient the staple cartridge 20 in relation to the anvil plate 108 of the anvil assembly 100 when the anvil assembly 100 and the shell assembly 18 are approximated . the anvil shaft 104 may also include one or more stabilization rings 130 ( only one is shown ) positioned about the anvil shaft 104 at a position to engage the shell assembly 16 when the anvil assembly 100 and the shell assembly 18 are approximated to provide added stability to the anvil assembly 100 . for a more detailed description of an anvil assembly including a stabilization ring , see u . s . pat . no . 8 , 424 , 535 which is incorporated herein by reference in its entirety . although the splines 126 and the stabilization ring 130 are shown to be formed integrally with the anvil shaft 104 , it is contemplated the either or both could be formed separately from the anvil shaft 104 and secured to the anvil shaft 104 using any known fastening technique including welding , crimping gluing or the like . referring to fig4 and 5 , each of the flexible legs 120 of the anvil shaft 104 defines a longitudinal channel 134 with an adjacent leg 120 . each longitudinal channel 134 includes an enlarged cutout or hole 136 formed at the distal end of the longitudinal channel 134 . the holes 136 are configured to secure a collet 150 within the longitudinal bore 122 of the anvil shaft 104 . in embodiments , the hole 136 is substantially circular although other configurations are envisioned . one or more of the flexible legs 120 may also include a bore 140 which is configured to receive a suture or the like ( not shown ). the suture can be used to allow a clinician to retrieve or position the anvil assembly 100 from or within a surgical site . the proximal end of each of the flexible legs 120 has an inner surface that defines a recess 160 ( fig7 ) such that the recesses 160 collectively define an annular recess 160 a ( fig9 ). the annular recess 160 a facilitates releasable engagement of the anvil assembly 100 to the stapling device 12 . referring also to fig6 , the collet 150 may be substantially rigid and is positioned within the longitudinal bore 122 defined by the anvil shaft 104 . the collet 150 is substantially cylindrical and defines a longitudinal bore 152 ( fig7 ) that is dimensioned to receive the trocar 22 ( fig1 ). a distal portion 154 of the collet 150 includes a plurality of cantilevered fingers 156 . each of the fingers 156 includes a protrusion 158 that is dimensioned and configured to be received in a respective one of the holes 136 ( fig5 ) formed in the anvil shaft 104 as described in further detail below . referring to fig7 - 9 , in order to assemble the collet 150 within the anvil shaft 104 , the distal end of the collet 150 is inserted into the proximal end of the longitudinal bore 122 of the anvil shaft 104 and slid distally in the direction indicated by arrow “ a ” in fig7 and 8 . the collet 150 is positioned to align the protrusions 158 with the longitudinal channels 134 positioned between the flexible legs 120 . when the protrusions 158 engage an inner wall of the flexible legs 120 , the fingers 156 are deflected inwardly in the direction indicated by arrow “ b ” in fig8 to facilitate passage of the collet 150 through the longitudinal bore 122 . when the protrusions 158 are moved into alignment with the holes 136 , the fingers 156 spring outwardly in the direction indicated by arrow “ c ” in fig9 to move the protrusions 158 into the holes 136 to secure the collet 150 within the longitudinal bore 122 . referring to fig1 , the trocar 22 includes a pointed distal end 30 and an enlarged proximal portion 32 that defines a shoulder 32 a . as known in the art , the proximal end of the trocar 22 is secured to an approximation mechanism ( not shown ) of the stapling device 12 ( fig1 ) to facilitate movement of the trocar 22 between retracted and advanced positions . when the trocar 22 is inserted into the longitudinal bore 122 of the anvil shaft 104 and the longitudinal bore 152 of the collet 150 in the direction indicated by arrow “ d ” in fig1 , the enlarged proximal portion 32 of the trocar 22 engages a proximal end of the flexible legs 120 of the anvil shaft 104 to urge the flexible legs 120 outwardly in the direction indicated by arrows “ e ”. when the enlarged proximal portion 32 of the trocar 22 is moved distally in the direction indicated by arrow “ d ” into alignment with the recess 160 defined at the proximal end of the flexible legs 120 , the flexible legs 120 return to their undeformed configuration to receive the enlarged proximal portion 32 of the trocar 22 . when the enlarged proximal portion 32 is received within the recess 160 , the shoulder 32 a on the enlarged proximal portion 32 of the trocar 32 engages a proximal wall 161 defining the recess 160 to secure the anvil shaft 104 to the trocar 22 . during an endoscopic surgical procedure , the anvil assembly 100 is grasped with a grasper ( not shown ) that is inserted through a small incision in the skin to position the trocar 22 within the longitudinal bore 122 of the anvil shaft 104 and secure the anvil assembly 100 to the trocar 22 of the surgical stapling device 12 . the collet 150 is positioned within the longitudinal bore 122 of the anvil shaft 104 and extends from a distal end of the flexible legs 120 towards the proximal end of the flexible legs 120 to support the flexible legs 120 and inhibit radial compression or other deformation of the flexible legs 120 that may result from pressure applied to the flexible legs 120 by a manipulating instrument ( not shown ). collet 150 may be formed from any suitable , medical grade material having a stiffness to perform the functions described herein . suitable materials include , for example , stainless steel or nylon . the collet 150 is secured within the longitudinal bore 122 of the anvil shaft 104 in a position that does not interfere with outward flexing of the flexible legs 120 and , thus , allows the anvil assembly 100 to be readily connected to the trocar 22 . persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non - limiting exemplary embodiments . it is envisioned that the elements and features illustrated or described in connection with one exemplary embodiment may be combined with the elements and features of another without departing from the scope of the present disclosure . as well , one skilled in the art will appreciate further features and advantages of the disclosure based on the above - described embodiments . accordingly , the disclosure is not to be limited by what has been particularly shown and described , except as indicated by the appended claims .

an anvil assembly is disclosed that includes an anvil shaft including a proximal portion and a distal portion and defining a first longitudinal bore . the proximal portion includes a plurality of flexible legs that define the first longitudinal bore dimensioned to receive a trocar of a stapling device . an anvil head assembly is secured to the distal portion of the anvil shaft and supports an annular anvil plate that a plurality of staple deforming pockets . the anvil assembly also includes a rigid collet defining a second longitudinal bore that is configured to receive the trocar of the stapling device . the rigid collet is supported within the first longitudinal bore and is positioned to prevent crushing of the plurality of flexible legs when the anvil assembly is manipulated with a grasper .

fig1 illustrates an optical ablation system 15 according to the present invention including an ablation instrument 10 and an electro - optic generator 11 . in fig1 optical energy in the form of light is supplied to ablation instrument 10 by electro - optical generator 11 . as used herein , the term &# 34 ; optical &# 34 ; is intended to include that portion of the electromagnetic spectrum including radiation in the ultraviolet , visible and infrared wavelengths . electro - optical generator 11 includes an optical energy source 12 , one or more energy coupling devices 14 , one or more optical filters 16 , one or more variable attenuators 18 which may also comprise a variable neutral density filter , one or more fiber optic bundles 20 , one or more thermocouple inputs 24 and control circuitry 22 . optical energy source 12 may be , for example , a laser , a halogen lamp , a conventional incandescent lamp or other optical energy source . optical energy source 12 may be a single source which provides light which is white or spectrally pure at a specific wavelength . alternatively , optical energy source 12 may include a plurality of light sources having any combination of wavelengths and power levels . optical energy source 12 is coupled to fiber optic bundle 20 by energy coupling lens 14 , optical filter 16 and variable attenuator 18 . energy coupling lens 14 focuses optical energy from optical energy source 12 through optical filter 16 and variable attenuator 18 onto the proximal end of fiber optic bundle 20 . the intensity and / or wavelength of optical energy source 12 may be controlled by , for example , signals from control circuit 22 transmitted through control line 72 . optical filter 16 may be a single frequency filter adapted to filter out all but one of the wavelengths generated by optical energy source 12 . alternatively , optical filter 16 may be a plurality of selectable filters from which a filter effective at one or more wavelengths may be chosen to selectively filter optical energy generated by optical energy source 12 . optical filter 16 may also be a spectral filter adapted to pass energy within a band of wavelengths . optical filter 16 may also be a filter wheel which contains a number of band pass filters . the wavelength of light filtered by optical filter 16 may be controlled by , for example , signals from control circuit 22 transmitted through control line ( s ) 70 . after passing through optical filter 16 , energy from optical energy source 12 passes through variable attenuator 18 . variable attenuator 18 may also be referred to as a variable neutral density filter . variable attenuator 18 is adapted to control the energy level of the light which is focused on to the proximal end of fiber optic bundle 20 . the setting of variable attenuator 18 may be controlled by , for example , signals from control circuit 22 transmitted through control line ( s ) 74 . the energy passed by variable attenuator 18 may be controlled by signals from control circuit 22 to ensure that the appropriate energy level is input to the proximal end of fiber optic bundle 20 . energy coupling lens 14 may include a plurality of energy coupling lenses , for example the three energy coupling lenses 14a , 14b and 14c illustrated in fig1 . optical filter 16 may include a plurality of optical filters , for example , the three optical filters 16a , 16b and 16c illustrated in fig1 . variable attenuator 18 may include a plurality of variable attenuators , for example , the three variable attenuators 18a , 18b and 18c illustrated in fig1 . in addition , fiber optic bundle 20 may include a plurality of fiber optic bundles , for example , the three fiber optic bundles illustrated in fig1 . the number of energy coupling lenses , optical filters , variable attenuators and fiber optic bundles will depend upon the design of the ablation system 15 , however , the number of coupling lenses , optical filters , variable attenuators and fiber optic bundles will generally correspond to the number of regions the ablation instrument is designed to separately heat within the body cavity being treated . electro - optic generator 22 includes temperature signal wires 24 which are adapted to relay signals representative of the temperature at selected points at the distal end of ablation instrument 10 to control circuit 22 . the number of temperature signal wires 24 will depend upon the design of ablation system 15 , however , the number of thermocouple inputs will generally correspond to a multiple of the number of regions the ablation instrument is designed to separately heat . in the embodiment of the ablation instrument illustrated in fig1 the electro - optic generator includes three temperature signal wires 24a , 24b and 24c . in one embodiment of the present invention , temperature signal wires 24 comprise a pair of wires which are connected through ablation instrument 10 to a thermocouple at a distal end of the ablation instrument . fiber optic bundles 20 and temperature signal wires 24 terminate at generator connector 19 which is adapted to mate with instrument connector 26 . in fig1 instrument connector 26 is shown in cutaway view to show fiber optic bundles 21a , 21b and 21c and to show thermocouple inputs 25a , 25b and 25c which are positioned within instrument connector 26 and flexible sleeve 27 . fiber optic bundles 20 exit electro - optic generator 11 at generator connector 19 where each fiber optic bundle 20a , 20b and 20c is butt - coupled to a corresponding fiber optic bundle 21a , 21b and 21c such that optical energy is transmitted from fiber optic bundles 20a , 20b and 20c to fiber optic bundles 21a , 21b and 21c , respectively . temperature signal wires 24 also exit electro - optic generator 11 at generator connector 19 where temperature signal wires 24a , 24b and 24c are connected to temperature signal wires 25a , 25b and 25c , respectively . fiber optic bundles 21 and temperature signal wires 25 pass through flexible sleeve 27 to instrument handle 28 and through instrument handle 28 to rigid sleeve 34 . instrument handle 28 includes connector 35 , fluid source connector 29 , sleeve retractor 32 , sleeve retractor stop 33 and fluid line 36 . flexible sleeve 27 , terminates at connector 35 while fiber optic bundles 21 and temperature signal wires 25 pass through connector support 27 and the central portion of instrument handle 28 to the central annulus of rigid sleeve 34 . fluid source connector 29 , which is adapted to receive a fluid source such as , for example , syringe 30 , is connected to fluid line 36 . in the embodiment of fig1 syringe 30 includes plunger 31 which is adapted to force fluid , for example air , through fluid line 36 . fluid line 36 extends from fluid source connector 29 to the annulus of rigid sleeve 34 . in instrument handle 28 as illustrated in fig1 sleeve retractor 32 is connected to sleeve collar 37 which is connected to rigid sleeve 34 such that rigid sleeve 34 may be retracted in the proximal direction by moving sleeve retractor 32 in the proximal direction . the travel of sleeve retractor 32 is limited by sleeve retractor stop 33 , thus limiting the proximal travel of rigid sleeve 34 . as rigid sleeve 34 is retracted , expandable sleeve tip 40 at the distal end of rigid sleeve 34 opens , releasing the balloon or other device positioned in the central annulus of rigid sleeve 34 at the distal end of sleeve 34 . fig2 is a cross sectional view of the ablation instrument illustrated in fig1 along view line 2 -- 2 . in fig2 fluid line 36 is surrounded by fiber optic bundles 21a , 21b and 21c and by temperature signal wires 25a , 25b and 25c . as illustrated in fig2 fiber optic bundles 21a , 21b and 21c each include one or more fiber optic fibers 38 which are adapted to transmit optical energy . temperature signal wires 25 are adapted to transmit signals representative of temperature . fluid line 36 is adapted to transmit fluid such as , for example , air . fig3 illustrates an optical ablation system according to the present invention including an ablation instrument and an alternative embodiment of an electro - optic generator . in the embodiment of electro - optic generator 11 illustrated in fig3 optical energy source 12 of fig1 is divided into a plurality of controllable optical energy sources 12a , 12b and 12c . in one embodiment of the present invention , the intensity of optical energy sources 12 is controllable and the energy from optical energy sources 12a , 12b and 12c is controlled by energy control signals from control circuit 22 which are transmitted through , for example , control lines 72 . each of energy sources 12a , 12b and 12c pass optical energy through energy coupling lenses 14a , 14b and 14c respectively . energy coupling lenses 14a , 14b and 14c focus optical energy on fiber optic bundles 20a , 20b and 20c through optical filters 16a , 16b and 16c respectively . in one embodiment of the present invention , optical filters 16 may include a plurality of selectable optical filters which may be selected by filter selection signals from control circuit 22 which are transmitted through , for example , control lines 70 . the number of energy coupling lenses , optical filters and fiber optic bundles will depend upon the design of ablation system 15 , however , the number of coupling lenses , optical filters and fiber optic bundles will generally correspond to the number of regions the ablation instrument is designed to separately heat within the body cavity being treated . in all other respects , the ablation system 15 illustrated in fig3 is substantially identical to the ablation system 15 illustrated in fig1 . fig4 is a cutaway view of a cross section of an expandable diffusing web 46 according to the present invention . in fig3 expandable defusing web 46 includes reflective coating 42 , balloon 44 , optical fiber mesh 47 and an adhesive layer 50 for attaching the fiber optic mesh to the balloon . reflective coating 42 may be , for example , a coating of silver or other reflective material which covers the outer surface of balloon 44 . balloon 44 may be constructed of , for example , mylar or other expandable balloon material . optical fiber mesh 47 may include optical fibers 48 , reflective fiber terminator 52 and fill threads 49 . fill threads 49 may be solid as illustrated in fig4 . alternatively , fill threads 49 may be made of an optically conductive material . optical fiber mesh 47 may be , for example , a light emitting woven light emitting panel which is manufactured by ploy - optic or by lumitex . reflective fiber terminator 52 is located at the end of optical fiber 48 to reflect any optical energy which reaches the end of optical fiber 48 without being diffused . fig5 is a cutaway side view of the distal end of ablation instrument 10 according to the present invention prior to deployment of expandable diffusing web 46 . in fig5 the distal end of rigid sleeve 34 , including expandable diffusing web 46 is disposed within uterus 56 . expandable diffusing web 46 is folded to fit within rigid sleeve 34 . the interior of uterus 56 is covered by an endometrial layer 58 . as rigid sleeve 34 is withdrawn , by , for example moving sleeve retractor 32 , expandable diffusing web 46 forces expandable sleeve tip 40 open , exposing expandable diffusing web 46 . fluid line 36 is connected to the proximal end of expandable diffusing web 46 such that a fluid , such as air , supplied at fluid source connector 29 fills the interior of expandable diffusing web 46 , forcing expandable diffusing web 46 to expand . fig6 is a cutaway side view if the distal end of ablation instrument 10 according to the present invention after deployment of expandable diffusing web 46 . in fig6 rigid sleeve 34 has been retracted , exposing expandable diffusing web 46 . expandable diffusing web 46 , which includes balloon 44 and optical fiber mesh 47 is expanded to fit against endometrial lining 58 of uterus 56 by filling balloon interior 60 with a fluid such as air . fluid line 46 connects balloon interior 60 to fluid source connector 29 . fig7 is a side view of a balloon 44 for use in the present invention . it will be recognized that balloon 44 may be shaped to fit within any body cavity , however , in the embodiment of the invention described herein , expandable diffusing web 46 is designed to be used within the uterus to destroy the endometrial lining . thus , balloon 44 illustrated in fig7 is shaped to fit within the uterus and to hold the optical fiber mesh firmly against at least a substantial portion of the endometrial lining . nor is it necessary that the invention be limited to the use of a balloon as an expandable element since any means of expanding expandable diffusing web 46 to position optical fiber mesh near or adjacent the interior lining ( e . g . the endometrium ) of the body cavity to be treated is within the scope of the present invention . in fig7 balloon 44 has been expand ed by filling interior 60 with an appropriate fluid , such as air , and the expanded balloon 44 takes on the shape of the interior of a uterus . fig8 is a side view of the distal end of ablation instrument 10 according to the present invention illustrating a portion of expandable diffusing web 46 which includes a first optical fiber mesh 47a . the embodiment of the invention illustrated in fig8 further includes a first thermocouple 62a . in fig8 optical fiber mesh 47a is disposed on the distal end of balloon 44 . in fig8 optical fiber mesh 47a includes optical fibers 48a which are interwoven with fill threads 49a . at their proximal end , optical fibers 48a of optical fiber mesh 47a are connected to the distal end of one of fiber optic bundles 21 which extend through rigid sleeve 34 , alternatively , optical fibers 48a of optical fiber mesh 47a may be a continuation of one of the optic fiber bundles 21 . for example , the proximal ends of fiber optics 48a may be gathered together to form an optical fiber bundle 51a which is connected to , for example , the distal end of fiber optic bundle 21a using , for example a butt - connector such as the one used to connect fiber optic bundle 20a with fiber optic bundle 21a , alternatively , fiber bundle 51a may be a continuation of the distal end of fiber optic bundle 21a . fiber optic bundle 21a is joined to or disperses to form optical fibers 48a such that optical energy is passed from fiber optic bundle 21a to optical fibers 48a , thus optical energy generated at optical energy source 12 may be transmitted through fiber optic bundle 20a to fiber optic bundle 21a and through fiber optic bundle 21a to optical fibers 48a of optical fiber mesh 47a . thermocouple 62a is positioned to detect the temperature of tissue adjacent optical fiber mesh 47a . temperature signal wires 25a , being connected to thermocouple 62a , relay a signal representative of the temperature at thermocouple 62a to temperature signal wires 24a which , in turn relay the signal to control circuit 22 . optical fiber mesh 47a , being positioned on balloon 44 , is held in place against the tissue to be treated by the expansion of balloon 44 as a result of the fluid supplied through fluid line 36 . fig9 is a side view of the distal end of ablation instrument 10 according to the present invention illustrating a portion of expandable diffusing web 46 which includes a first optical fiber mesh 47a and a second optical fiber mesh 47b . the embodiment of the invention illustrated in fig9 further includes a first thermocouple 62a and a second thermocouple 62b . in fig9 a second optical fiber mesh 47b has been wrapped around the distal end of the balloon illustrated in fig8 to increase the surface area of balloon 44 covered by optical fiber mesh 47 . thus , the previous description of the instrument with respect to fig8 is applicable with respect to like elements of fig9 . in addition to the elements described with respect to fig8 fig9 illustrates optical fiber mesh 47b which includes optical fibers 48b which are interwoven with fill threads 49b . at their proximal end , optical fibers 48b of optical fiber mesh 47b are connected to the distal end of one of fiber optic bundles 21 which extend through rigid sleeve 34 . for example , the proximal ends of fiber optics 48b may be gathered together to form an optical fiber bundle 51b which is connected to , for example , the distal end of fiber optic bundle 21b using , for example , a butt - connector such as the one used to connect fiber optic bundle 20b with fiber optic bundle 21b , alternatively , fiber bundle 51b may be a continuation of the distal end of fiber optic bundle 21b . fiber optic bundle 21b is joined to optical fibers 48b such that optical energy is passed from fiber optic bundle 21b to optical fibers 48b , thus optical energy generated at optical energy source 12 may be transmitted through fiber optic bundle 20b to fiber optic bundle 21b and through fiber optic bundle 21b to optical fibers 48b of optical fiber mesh 47b . thermocouple 62b is positioned on balloon 44 to detect the temperature of tissue adjacent optical fiber mesh 47b . temperature signal wires 25b , being connected to thermocouple 62b , relay a signal representative of the temperature at thermocouple 62b to temperature signal wires 24b which , in turn , relay the signal to control circuit 22 . optical fiber mesh 47b , being positioned on balloon 44 , is held in place against the tissue to be treated by the expansion of balloon 44 as a result of the fluid supplied through fluid line 36 . fig1 is a side view of the distal end of ablation instrument 10 according to the present invention illustrating a portion of expandable diffusing web 46 which includes a first and optical fiber mesh 47a , a second optical fiber mesh 47b and a third optical fiber mesh 47c . the embodiment of the invention illustrated in fig1 further includes a first thermocouple 62a , a second thermocouple 62b and a third thermocouple 62c . in fig1 , a third optical fiber mesh 47c has been wrapped around the distal end of the balloon illustrated in fig8 and fig9 to increase the surface area of balloon 44 covered by optical fiber mesh 47 . thus , the previous description of the instrument with respect to fig8 and fig9 is applicable with respect to like elements of fig1 . in addition to the elements described with respect to fig8 and fig9 fig1 illustrates an optical fiber mesh 47c which includes optical fibers 48c which are interwoven with fill threads 49c . at their proximal end , optical fibers 48c of optical fiber mesh 47c are connected to the distal end of one of fiber optic bundles 21 which extend through rigid sleeve 34 . for example , the proximal ends of fiber optics 48c may be gathered together to form an optical fiber bundle 51c which is connected to , for example , the distal end of fiber optic bundle 21c using , for example , a butt - connector such as the one used to connect fiber optic bundle 20c with fiber optic bundle 21c , alternatively fiber bundle 51c may be a continuation of the distal end of fiber optic bundle 21c . fiber optic bundle 21c is joined to optical fibers 48c such that optical energy is passed from fiber optic bundle 21c to optical fibers 48c , thus optical energy generated at optical energy source 12 may be transmitted through fiber optic bundle 20c to fiber optic bundle 21c and through fiber optic bundle 21c to optical fibers 48c of optical fiber mesh 47c . thermocouple 62c is positioned on balloon 44 to detect the temperature of tissue adjacent optical fiber mesh 47c . temperature signal wires 25c , being connected to thermocouple 62c , relay a signal representative of the temperature at thermocouple 62c to temperature signal wires 24c which , in turn , relay the signal to control circuit 22 . optical fiber mesh 47c , being positioned on balloon 44 , is held in place against the tissue to be treated by the expansion of balloon 44 as a result of the fluid supplied through fluid line 36 . the embodiment of the invention illustrated in fig1 is adapted to controllably heat three separate regions within the uterus of a human patient to selectively destroy the endometrial layer within those regions . the energy and depth of penetration of the optical energy may be controlled by controlling the energy level and wavelength of the energy transmitted to the proximal end of each fiber optic bundle 20a , 20b and 20c . longer wavelengths penetrate deeper into tissue . shorter wavelengths , for example , blues and greens , may be used to achieve surface heating . thus , depending on the effect that is desired , different wavelength of optical energy may be selected . optical energy is transmitted through optical bundles 20 to optical bundles 21 and optical bundles 51 . optical energy which passes through optical bundles 51 is diffused by optical fiber mesh 47 of expandable diffusing web 46 . reflective coating 42 acts to reflect optical energy away from balloon 44 and into tissue surrounding expandable diffusing web 46 . the depth of penetration of the optical energy into surrounding tissue will be a function of a number of factors , including the wavelength of the optical energy radiated by expandable diffusion web 46 and the distance from the expandable diffusion web 46 to the tissue to be treated . the rate at which the tissue is heated will also depend upon a number of factors , including the output energy generated by optical energy source 12 , the losses in electro - optic generator 11 and ablation instrument 10 , the distance from the expandable diffusion web 46 to the tissue to be treated and the wavelength of the optical energy . however , by monitoring the tissue as it is treated using , for example , thermocouples 62 , the surgeon may control the temperature of the tissue being treated with relative accuracy . in use a surgeon will introduce the distal end of ablation instrument 10 into the body cavity of a patient such that expandable sleeve tip 40 is positioned at a predetermined depth within the body cavity . for the purposes of this discussion , the body cavity to be treated will be the uterus of a female human being . it will be recognized that , with slight modification , the present invention may be used to treat other body cavities . once sleeve tip 40 is inserted into the uterus 56 as illustrated in fig5 sleeve retractor 32 may be used to slide rigid sleeve 34 back away from expandable diffusing web 46 . as rigid sleeve 34 is retracted , expandable diffusing web 46 forces expandable sleeve tip 40 open . once sleeve retractor 32 reaches its proximal most travel point it is stopped by sleeve retractor stop 33 which prevents rigid sleeve 34 from retracting further . once rigid sleeve 34 is retracted , expandable diffusing web 34 may be expanded to contact the interior of the uterus by , for example inflating balloon 44 by injecting an appropriate fluid , such as , for example air into balloon interior 60 . fluid is introduced into balloon 44 through fluid line 36 which is connected to fluid source connector 29 which , in the embodiment illustrated in fig1 is connected to a syringe and plunger which may be used to inflate or deflate balloon 44 . expandable diffusing web 46 , being shaped to fit the body cavity , e . g . the uterus , being treated , is designed to force optical fiber mesh 47 against a substantial portion of the interior surface of the body cavity . thus , when expandable diffusing web 46 is fully expanded , optical fiber mesh 47 is positioned directly adjacent or in direct contact with endometrium 58 of uterus 56 . once expandable diffusing web 46 is positioned within uterus 56 , optical energy may be supplied to optical fiber mesh 47 by turning on optical energy source 12 . once optical energy source 12 is turned on , the light radiated by optical energy source 12 is focused on the proximal end of optical fiber bundle 20 by energy coupling lens 14 . as optical energy passes through optical filter 16 , it is filtered to remove unwanted wavelengths . as optical energy passes through variable attenuator 18 the energy level is attenuated . therefore , the optical energy focused upon fiber optic bundle 20 is filtered and attenuated such that it is optical energy of a selected wavelength and energy level . optical energy focused upon the proximal end of fiber optic bundle 20 is transmitted through fiber optic bundle 20 to fiber optic bundle 21 and from fiber optic bundle 21 to expandable diffusing web 46 where it is radiated into the endometrial layer from optical fiber mesh 47 . where different optical energy levels or wavelengths are to be transmitted to different regions of the endometrium , a plurality of energy coupling lenses 14a - 14c , optical filters 16a - 16c and variable attenuators 18a - 18c may be used to focus filtered optical energy onto a plurality of fiber optic bundles 20a - 20c as illustrated in fig1 . alternatively , where different optical energy levels or wavelengths are to be transmitted to different regions of the endometrium , a plurality of optical energy sources 12a - 12c , energy coupling lenses 14a - 14c and optical filters 16a - 16c may be used to focus filtered optical energy onto a plurality of fiber optic bundles 20a - 20c as illustrated in fig2 . the optical energy focused on optical bundles 20a - 20c may then be transmitted through optical fiber bundles 21a - 21c to each optical fiber mesh 47a - 47c . once the optical energy reaches expandable diffusing web 46 , it is radiated by optical fibers 48 which are woven with fill threads 49 to form optical fiber mesh 47 . radiation from optical fibers 48 which is not directed into the tissue adjacent optical fiber mesh 47 is reflected by reflective coating 42 as illustrated in fig4 . thus , both the energy radiated toward the tissue and the reflected energy is absorbed by the tissue adjacent to fiber optic mesh 47 . further , since the energy is transmitted optically , it is not necessary for the tissue to be directly adjacent fiber optic mesh 47 as the radiated energy will be absorbed by any tissue illuminated by the energy from the mesh . this arrangement provides for uniform escape or emission of energy focused on the fiber optic bundles 20 in fiber optic generator 11 . further , in an arrangement according to the present invention , energy is evenly radiated from the outside of the expandable diffusing web , and is , therefore absorbed by the endometrial lining of the uterus causing temperature of the tissue to rise . the control sequence for control circuit 22 of the electro - optic generator illustrated in fig1 is illustrated in fig1 . once expandable diffusing web 46 has been positioned and inflated as described previously , optical energy may be supplied to expandable web 46 to heat endometrial lining 58 . the first step in supplying optical energy to endometrial lining 58 is to select an appropriate wavelength . in particular , red and near infrared wavelengths would be selected for heating deep ( e . g . 0 - 10 millimeters ) into uterine tissue . ultraviolet , blue or green wavelengths would be used for heating uterine tissue to a depth of , for example , ( 0 - 3 millimeters ). once the appropriate optical energy wavelength has been selected by , for example , adjustment of optical filter 16 or by appropriate selection of optical energy source 12 , optical energy may be supplied to expandable web 46 . the energy level or intensity of the optical energy supplied to expandable web 46 may be controlled by controlling the attenuation of variable attenuators 18 or by controlling the intensity of optical energy source 12 . temperature feedback from thermocouple 62 may be used to adjust the energy level supplied to fiber optic bundles 20 . thus , the temperature of the body lining being treated is controlled by controlling the energy level supplied to expandable web 18 while the depth of penetration of the energy supplied to expandable web 46 is controlled by controlling the wavelength of the optical energy supplied to fiber optic bundles 20 . the flow diagram of fig1 illustrates the control sequence for the electro - optic generator illustrated in fig1 . the temperature of endometrial lining 58 is sensed by , for example , thermocouple 62 which provides a signal to control circuit 22 through temperature signal wires 24 and 25 . as illustrated in fig1 , control circuit 22 , in step 67 , senses the temperature at thermocouple 62 and produces a signal 100 which is representative of the temperature measured at thermocouple 62 . in step 68 , signal 100 is compared to a predetermined set point temperature such as , for example , any temperature between 42 ° c . and 100 ° c . for a time sufficient to destroy the inner lining of the organ in question . if the temperature represented by signal 100 is lower than the set point temperature , control circuit 22 generates a signal 103 . in step 71 , signal 103 causes control circuit 22 to decrease the attenuation of the optical energy focused on optical fiber bundle 20 , thus increasing the optical energy supplied to expandable web 46 . once the attenuation has been reduced , control circuit 22 generates a signal 105 which causes control circuit 22 to return to step 67 where the temperature is measured again and a new signal 100 is generated . once the temperature represented by signal 100 reaches the set point temperature control circuit 22 , in step 69 , generates a signal 106 which is representative of the time the endometrium has been at the desired temperature . the time represented by signal 106 is compared , in step 72 to a predetermined set time and if the time represented by signal 106 is less than the predetermined set time , control circuit 22 generates signal 107 which returns control circuit 22 to step 67 . if during the control cycle , the signal 100 rises above the set point temperature , then signal 102 is generated , causing control circuit 22 to increase attenuation at variable attenuators 18 , thus decreasing the optical energy delivered to expandable diffusing web 46 . once the actual time at the desired temperature , represented by signal 106 , reaches the predetermined set time in step 72 , signal 108 is generated indicating , in step 73 , that the procedure is complete and generating signal 109 which turns off optical energy source 12 in step 74 . the flow diagram of fig1 illustrates the control sequence for the electro - optic generator illustrated in fig2 . the temperature of endometrial lining 58 is sensed by , for example , thermocouple 62 which provides a signal to control circuit 22 through temperature signal wires 24 and 25 . as illustrated in fig1 , control circuit 22 , in step 80 , senses the temperature at thermocouple 62 and produces a signal 200 which is representative of the temperature measured at thermocouple 62 . in step 81 , signal 200 is compared to a predetermined set point temperature . if the temperature represented by signal 200 is lower than the set point temperature , control circuit 22 generates a signal 203 . in step 84 , signal 203 causes control circuit 22 to increase the optical energy from optical energy source 12 which increases the intensity of the optical energy focused on optical fiber bundle 20 , thus increasing the optical energy supplied to expandable web 46 . once optical energy has been increased , control circuit 22 generates a signal 205 which causes control circuit 22 to return to step 80 where the temperature is measured again and a new signal 200 is generated . once the temperature represented by signal 200 reaches the set point , temperature control circuit 22 , in step 82 , generates a signal 206 which is representative of the time the endometrium has been at the desired temperature . the time represented by signal 206 is compared , in step 85 to a predetermined set time and , if the time represented by signal 206 is less than the predetermined set time , control circuit 22 generates signal 207 which returns control circuit 22 to step 80 . if during the control cycle , the signal 200 rises above the set point temperature , then signal 202 is generated , causing control circuit 22 to decrease the optical energy from optical energy source 12 , which decreases the intensity of the optical energy focused on optical fiber 20 , decreasing the energy delivered to expandable diffusing web 46 . once the actual time at the desired temperature , represented by signal 206 , reaches the predetermined set time in step 85 , signal 208 is generated indicating , in step 86 , that the procedure is complete and generating signal 209 which turns off optical energy source 12 in step 87 . in operation , ablation instrument 10 would be connected to electro - optic generator 11 and the distal end of instrument 10 would be inserted into the appropriate body organ , for example , into the uterus 56 . rigid sleeve 34 would then be retracted using sleeve retractor 32 , thereby exposing expandable diffusing web 46 which includes balloon 44 . balloon 44 is inflated using , for example , balloon inflator syringe 30 which includes plunger 30 . once balloon 44 is inflated forcing expandable diffusing web 46 to conform to the interior of uterus 56 , electro - optic generator 11 is activated , thus delivering optical energy to optical fibers 48 of optical fiber mesh 47 on expandable diffusing web 46 . control circuit 22 is then used to monitor the heating of endometrial layer 58 of uterus 56 through thermocouple ( s ) 62 . control circuit 22 acts to bring endometrial layer 58 up to a desired temperature , hold endometrial layer 58 at that temperature for a predetermined length of time and then turn off optical energy to the endometrial layer . expandable diffusing web 46 may then be collapsed by deflating balloon 44 using , for example syringe 30 . once expandable diffusing web 46 is deflated , it may be retracted from uterus 56 . use of an ablation instrument according to the present invention may be advantageous , when compared to electrosurgical or other apparatus for use in endometrial ablation , for example : light energy may be less likely to interfere with the operation of the thermocouples ; a light diffusing fiber - optic web may be more adaptable to expansion than rf electrodes ; contact with the uterine wall is not required as it may be in an rf device ; it is possible to control the depth of heating by controlling the wavelength of the optical energy applied to the endometrial lining . according to one embodiment of the present invention , light energy from optical energy source 12 , which may be , for example , common projection lamps , may be used to uniformly heat the endometrium 58 ° to 70 ° c . and thereby ablate the endometrium . the array of fiber - optic mesh or webs 47 are connected individually to an array of high intensity lamps 12 via fiber - optic cables 20 and 21 . fiber optic mesh 47 may heating of the endometrium 58 is achieved through absorption of the optical radiation transmitted through fiber optic cables 20 and 21 . the temperature of each fiber optic web , for example fiber optic webs 47a - 47c , is monitored by a thermocouple , for example 62a - 62c , which , through a feedback loop including temperature signal wires 24 and 25 which are connected to control circuitry 22 , controls the intensity of its associated lamp 12 . in this embodiment , fiber - optic mesh 47 and thermocouples 62 cover the outside of an inflatable silvered mylar pouch or balloon 44 . balloon 44 is inserted into the uterus and then inflated . inflation brings fiber - optic webs 47 and thermocouples 62 into contact with the endometrium or endometrial layer 58 . lamps 12 are then turned on and the temperature of the endometrium is monitored intensity of the optical energy supplied to fiber optic webs 47 is controlled by monitoring feedback from thermocouples 62 until therapy is complete . the silvered surface of mylar balloon 44 directs all the optical radiation into the endometrium for heating . while preferred embodiments of the present invention have been shown and described herein , it will be obvious to those skilled in the art that such embodiments are provided by way of example only . numerous variations , changes , and substitutions will now occur to those skilled in the art without departing from the invention . accordingly , it is intended that the invention be limited only by the spirit and scope of the appended claims .

a method of performing endometrial ablation comprising heating entire surface of the endometrium to a temperature of between 45 ° c . and 70 ° c . to destroy the cells of the endometrial lining while maintaining the average temperature of the myometrium at a temperature below approximately 42 ° c . an apparatus for performing an endometrial ablation comprising an expandable membrane such as a balloon adapted to fit within the uterus and contact the endometrial lining when expanded . a web of light diffusing fiber - optic cables arranged on the outer surface the balloon such that the web contacts the endometrial lining of the uterus when the balloon is expanded . the fiber - optic web is connected to an array of high intensity lamps via a series of fiber - optic cables . the temperature of the endometrium is monitored by a of a series of temperature sensors arranged upon the surface of the balloon .

1 indicates the tank containing the mixture of vegetable and / or animal natural products , each one in a clean and fragmented state , containing one or more primary mineral elements in addition to those in smaller quantities , combined with organic substances to be eliminated ; 2 indicates the heated cell , normally at a temperature included between 200 ° and 900 ° c ., in which the mixture coming from container 1 is mineralised , therefore the organic portion is normally separated in vapours and fumes . the mineralised complex in container 3 is a mineral complex characterised by a qualitative and quantitative composition of the chosen primary mineral elements , each one combined with a plurality of mineral elements already present , sometimes in minimum measures , on the vegetal and / or animal products from which they are originally produced and contained . the product coming out from group 3 is in one case conveyed directly to chamber 6 , and in the other case conveyed to mixer 4 in which it is mixed with other active principles coming from container 5 in order to originate in chamber 6 the mixture that is to be transformed into capsules or tablets , then to be packed and after distributed on the market . in the general formulation the production process of a mineral complex first foresees the quantitative determination of the metals that one wishes to integrate , hence a selection of the vegetal and / or animal raw materials that present a particularly high content of the above - mentioned metals . after having accomplished the choice of the organic raw materials to be used , the process through which the wanted mineral complex is obtained , can be described in a detailed way as follows : the chosen raw materials are analysed to make sure that the element is to be integrated is constant in them . the selected raw materials are dried , then individually cut and sieved until obtaining a uniform granulometry that is adapted for being mineralised . the previously processed raw materials as described above , are eventually mixed between them in the right proportion in order to obtain in the final complex the content of principal elements as wanted in the ratio . the aforesaid mixture is distributed on trays of stainless steel until reaching a layer of 5 cm . for each tray . the trays are stacked in a muffle one on top of the others , with some space between them for combustion fumes to escape . the normally methane operating muffle is programmed in such a way to reach within it a temperature of approximately 200 - 400 ° c . for 1 - 3 hours , then it is raised to a temperature of about 500 - 900 ° c . for 3 - 5 more hours , or anyway until the complete removal of the organic portion from the mixture of drugs introduced . the first period of time , at a temperature of 200 - 400 ° c ., is essential in order to obtain a perfect light coloured mineralised product , without any carbonised organic products . the mineralised product obtained from the muffle is subjected to a quantitative analysis for being titrated , at least in its main elements , and to a control in order to verify the absence of elements recognised as toxic . it can be conveyed in the packaging division , or first mixed with additional chosen active principles , and hence sent to the packaging . however , the invention is illustrated here as follows with reference to two applications for the production of different highly concentrated mineralised natural complexes . the proportion for the mixing has been chosen according to the content of iron in the single drugs above - indicated , in particular : the selected vegetal drugs have been cut until reaching a uniform granulometry that is adequate to be mineralised . the optimal granulomethy is the following : the aforesaid fragmented mixture has been distributed on the stainless steel trays until reaching a layer of about 5 cm . of drug for each tray . the trays are stacked one on top of the other , with some space between them for the combustion fumes to escape . the methane operating muffle is programmed to reach within it a temperature of approximately 300 ° c . for a time of 2 hours at first , then it is raised and kept at a temperature of approximately 700 ° c . for 4 more hours . the first step at 300 ° c . is essential in order to obtain a perfect white coloured final product completely inorganic . the mineralised product is encapsulated in gelatine capsules with a final weight of about 500 mg . in this process the obtained mineralised complex contains all the mineral substances originally contained in the raw materials in form of oxides and other salts . the composition of the mineralised complex is the following : ______________________________________element concentration in the complex in mg / g______________________________________iron 7 . 73 calcium 109 . 8 zinc 0 . 19 magnesium 21 . 75 potassium 85 . 0 sodium 9 . 3 copper 0 . 03 manganese 0 . 49______________________________________ due to the high concentration of iron and the relatively high specific weight of the mineralised complex , only four capsules a day are sufficient to obtain a good daily integration of such element ( the daily recommended ration of iron is 14 mg . according to the italian law ). as a matter of fact , the solubility , and therefore the bio - availability with a ph : 1 , is extremely high : in fact 2 g . of product are 93 . 05 % soluble in one litre of hydrochloric acid with a ph : 1 at 37 ° c . ( liquid simulating gastric juice ). the proportions for the mixing have been chosen according to the calcium content in the single above - mentioned drugs , in particular : the selected vegetable drugs have been cut until reaching a uniform granulometiy , adequate for being mineralised . the optimal granulometry for each drug is the following : after having mixed the drugs , separately chopped up by following the above - mentioned granulometry , the mixture is distributed on steel trays until reaching a layer of 5 cm . of drug for each tray . the trays are stacked one on top of each other , with some space between them for the combustion fumes to escape . the muffle , normally heated with methane , is programmed in such a way to reach within it a temperature of approximately 300 ° c . for 2 hours , then it is raised and kept at a temperature of about 700 ° c . for 4 more hours . the first step at 300 ° c . is essential in order to obtain a perfect white coloured final product and completely inorganic . the mineralised product is encapsulated in gelatine capsules with a final weight of about 500 mg . in this process the obtained mineralised complex contains all the mineral substances originally contained in the raw materials in form of oxides and other salts . the composition of the obtained mineralised complex is the following : ______________________________________element concentration in the complex in mg / g . ______________________________________iron 1 . 9 calcium 299 . 5 zinc 0 . 46 magnesium 33 . 74 potassium 94 . 6 sodium 8 . 5 copper 2 . 5 manganese 4 . 08______________________________________ due to the high concentration of calcium and the relatively high specific weight of the mineralised complex , only five capsules per day are sufficient to obtain a good daily integration of calcium ( in italy the recommended daily ration of calcium is of 800 mg .). in fact , the solubility , and so the bio - availability with a ph : 1 , is extremely high : 2 g . of product are 77 . 15 % soluble in a little of hydrochloric acid with a ph : 1 at 37 ° c . ( liquid simulating gastric juice ). the process is repeated for any other individually chosen vegetal and / or animal product , or in combination with other organic products characterised by a high content of metal or metals , through which the integration of mineral oligoelements in humans , animals or plants is intended to be operated .

the invention concerns a highly concentrated mineralised natural complex , characterised by at least one main mineral element quantified with nutritional and / or dietetic integrator properties and by other mineral elements obtained in the complex from the mineralization of vegetal and / or animal products . moreover , it concerns the method for its production consisting in using vegetal and / or animal organic substances , having a high content of oligominerals , in carrying out their fragmentation , their mixing and the mineralization until the inorganic part is completely separated from the organic part , and then in transforming the aforesaid inorganic part in forms of easy commercialization .

illustrated in fig1 and 3 is the exterior box or container 10 for the curtain puller . the box 10 may be constructed of metal or plastic halves that merely snap together or are fastened together with mechanical fasteners . adjacent to the top of the box is a separate cover piece 12 open at the top and affixed to the front of the box 10 . within the cover 12 is a drive pulley 14 mounted on a motor drive shaft extending from a small electric motor 16 within the box 10 . the pulley 14 engages the drapery or curtain cord 18 in turn extending downwardly about the pulley 14 and upwardly to the curtain rod ( not shown ). thus , the electric motor 16 drives the curtain cord 18 to open or close the curtains or drapes . in other words , the motor 16 moves the object or curtains from an open first position to a closed second position or vice versa . below the box is a bracket 20 that may be attached to the wall of a house adjacent a window with mechanical fasteners through the holes 22 in the bracket . within the bracket 20 is a transverse rod 24 to which a pair of springs 26 are attached at their lower end . the upper ends of the springs 26 are attached to a second transverse rod 28 in turn affixed to the inside of the back of the box 10 . the springs 26 provide suitable tensioning for the curtain cord 18 . atop the box 10 is a small shield 30 which may be manually rotated about a vertical axis . the shield 30 has an opening 32 to permit light to enter therein . inside the shield is a photocell connected to the internal circuitry of the curtain puller . a 110 volt ac power supply cord as indicated at 34 extends into the box 10 and is attached to a rectifier and motor power circuit indicated at 36 . also inside the box 10 is a printed circuit board 38 to which are attached the electric elements comprising the control circuit for the curtain puller . as shown the box 10 encloses the entire electric control and power supply for the curtain puller . the box 10 is not substantially larger than a conventional spring tensioner for a curtain cord loop . fig4 a , 4b , and 4c illustrate the control and power circuitry for the curtain puller . with the exception of the 110 volt ac power supply cord 34 and plug for the electrical power to the curtain puller , the control and power circuitry is entirely contained within the box 10 . referring in particular to fig4 c , a fuse f1 and transformer t1 in the 110 volt ac supply provide power to a regulator circuit comprising a diode bridge 40 and an integrated circuit regulator reg - 1 . the regulator circuit provides 12 volts dc power to the control circuit illustrated in fig4 a and 4b and to the isolator circuit including opto - isolators ic1 and ic2 shown in fig4 c . the transformer t1 also provides ac power at reduced voltage to the pulley drive motor 16 through the triacs q1 and q2 . triacs q1 and q2 are in turn triggered by signals respectively from opto - isolators ic1 and ic2 . in other words , the transformer and regulator circuit act as a power supply means for supplying power from the 110 ac power source to the control circuit and motor . a suitable motor 16 is a reversible 24 volt 60 cycle ac motor . a reversible dc motor might be substituted for motor 16 with suitable changes in the power supply to provide dc current and solid state switching means in substitution for triacs q1 and q2 . the opto - isolators or optical couplers ic1 and ic2 provide electrical isolation between the ac power for the motor 16 and the low voltage substantially dc control signals in the control circuit shown in fig4 a and 4b . the signal through the opto - isolators ic1 and ic2 is provided by a 12 volt dc signal in turn controlled by a pair of transistors q3 and q4 . the pair of optically isolated connection circuits is between transistor q4 and triac q1 and between transistor q3 and triac q2 . thus , the control of rotational direction of the motor 16 is determined by a signal from opto - isolator ic1 to triac q1 , or for the other direction , by the signal from opto - isolator ic2 to triac q2 . the control circuit identified by the reference 38 to a printed circuit board within the box 10 comprises in fig4 a and 4b a photo - electric cell q5 which is contained within the hooded cover 30 at the top of the box 10 . in response to a sufficient increase or decrease in light the photo cell q5 provides an input to an integrated circuit ic3 which in turn provides an output at pin 7 of a sudden up or down voltage change as indicated by arrows 42 and 44 . in other words , the photoelectric cell q5 is a light sensing means for detecting changes in levels of light , i . e ., presence or absence of light in the daytime and nighttime , respectively . the sudden change in voltage up 42 or down 44 is provided as an input to pin 4 of integrated circuit ic4 which in turn massages the signal to provide through integrated circuit ic7 a reset and start signal illustrated by the &# 34 ; one shot &# 34 ; 46 at pin 4 of integrated circuit ic7 . the reset and start &# 34 ; one shot &# 34 ; 46 in turn is provided to pin 6 of a dual timer integrated circuit ic5 . a suitable integrated circuit ic4 is a motorola monostable multivibrator mc14538b or equivalent . integrated circuit ic5 is a national semiconductor dual timer lm556 or equivalent . the reset and start &# 34 ; one shot &# 34 ; 46 is also provided through integrated circuit ic8 from pin 3 to the base of transistor q6 , which with the associated circuitry and dual timer ic5 provides a ramp function timing signal that increases in voltage continuously from the moment that the &# 34 ; one shot &# 34 ; reset and start signal is received . typically , this ramp function , as indicated schematically by arrow 48 on the xy plot adjacent transistor q6 , constantly increases the charge on capacitor c6 until a prespecified voltage is reached . each time the signal from the photocell q5 passes a threshold of increasing light or decreasing light an up or down voltage change is generated by integrated circuit ic3 and sensed at the base of transistor q6 to reset the ramp function output 48 by discharging capacitor c6 . typically the ramp function circuit elements connected between transistor q6 and pins 1 , 2 and 3 of integrated circuit ic5 are specified to provide about a 15 minute time period from start or reset until a specified voltage is reached . thus , short term changes in light level sensed by the photo electric cell q5 do not result in actuation of the control circuit beyond resetting the ramp function output 48 . once the specified ramp function voltage is reached , the second timer of integrated circuit ic5 is actuated by the output 1 at pin 5 to t2 pin 8 . the second timer includes the circuit elements connected to pins 7 , 11 , 12 and 13 of integrated circuit ic5 . the potentiometer p1 provides adjustable means for setting the length of time the motor 16 operates by setting the specified ramp function maximum voltage for the second timer . with actuation of the second timer an output 2 signal at pin 9 is provided to pin 3 of integrated circuit ic6 which acts as a flip - flop or latch to determine the current state or position of the motor 16 and thereby determine the current position of the curtain . a suitable integrated circuit ic6 is motorola dual flip - flop mc14013b or equivalent . the flip - flop integrated circuit ic6 thereby permits or does not permit the motor to operate depending upon the direction of operation of the motor the previous time the motor was actuated to move the curtain . in other words , the flip - flop or latch acts as a latching means for determining the current position of the motor in either of the first and second positions and for actuating the motor to move the object or curtain to the position opposite the current position of the object or curtain . the status of the integrated circuit ic6 can be easily determined by the light emitting diode d8 which is connected to pin 9 of integrated circuit ic6 and illuminated when the curtain is in the closed position . a by - pass or a manual switch s2 is also provided so that the curtain can be conveniently opened or closed as desired during the night or during the day . the manual closure or opening of the curtain is sensed through the connection to pins 2 and 5 of integrated circuit ic6 . the output from integrated circuit ic6 pins 1 and 2 respectively provide one - half of the control to the base of transistor q4 or the base of transistor q3 thereby determining the direction of rotation . the other half of the control is provided by the output at pin 9 of the dual timer ic5 . once actuated by the output at pin 9 of integrated circuit ic5 the motor operates for a period of time necessary to move the curtain as set by the exterior circuitry and potentiometer p1 of the second timer of dual timer ic5 . the second timer circuit is also actuated by engaging the manual switch s2 to also start the motor running with the second timer . in either case the motor runs for a set period of time sufficient to open or close the curtain . in summary , the flip - flop circuitry only permits the motor to operate when either the signal from integrated circuit ic3 or from the manual switch s2 , if thrown , provides for movement of the curtain opposite to that of the previous movement of the curtain .

an automatic electro - mechanical device for opening and closing a curtain or drapery in response to changed light striking a photoelectric cell on the device . the device comprises a miniature high torque reversible electric motor and control packaged in a container of substantially the same size as a conventional cord tensioner of curtains or draperies . to close the drapes at sun - down and open the drapes at sun - up automatically without actuation if the lighting changes for short periods of time , the device comprises a dual timer circuit with individual ramping circuits . one timer circuit monitors the sustained presence or absence of light for a predetermined amount of time . the other timer regulates the motor drive run time . a flip flop circuit signals the current state of the curtains or drapes by providing memory of the last directional movement of the motor .

as shown in fig3 , the present invention is a container includes a cup ( 1 ), a rigid lining ( 2 ) mounted inside the cup ( 1 ). the lining ( 2 ) is a prefabricated component combined to the cup ( 1 ) by injection molding . in other words , the lining ( 2 ) is first placed in the mode and then a transparent or translucent acrylic cup ( 1 ) is formed to wrap over the circumference of the lining ( 2 ) integrally as a whole by injection molding ; finally , they are never detached from each other . lining ( 2 ) is shaped as a half - mask , that is , the lining ( 2 ) only shields the lower half portion of the cup ( 1 ) but the upper half portion of the cup ( 1 ) is not shielded by the lining ( 2 ). users can see vegetable or fruit cubes are whipped or thrashed in the cup ( 1 ). if the lining ( 2 ) is shaped as a whole - mask ( as shown in fig1 ), the upper and lower half portions of the cup are shielded by the lining ( 2 ). users only look down on the vegetable or fruit cubes whipped or thrashed in the cup ( 1 ). lining ( 2 ) is combined to the inner wall of the cup ( 1 ) to form a shield screen characterized in that a number of teeth ( 21 ) projected from the inner wall of the lining ( 2 ) applied to grate fibers of vegetable and fruit . teeth ( 21 ) can be arranged in parallel with one another , but they are all arrayed in alignment with each other finally to form a crossed or columned shape of teeth array . rather , the lining ( 2 ) can be made of metal , glass , alloy , or non - alloy material , which is with a hardness rather rigid than the acrylic cup ( 1 ). lining ( 2 ) is an annular member formed integrally as a whole one , but which is preferred in the shape of polygon . a lining base ( 21 ) can be added to the bottom of the cap ( 1 ) as a shield screen thereof . the top end of the lining ( 2 ) has an l type wall ( 25 a ) bended outward and upward , the bottom end of the lining ( 2 ) has an l type wall ( 25 b ) bended inward and downward respectively . both l type walls ( 25 a , 25 b ) are embedded into the inner wall of the cup ( 1 ) to eliminate the permeation of liquid through a chink on the wall . cup ( 1 ) has a handle ( 12 ) and a spout ( 13 ). several vertical ribs ( 11 ) are protruded from the inner wall of the cup ( 1 ); several vertical stopper members ( 22 ) corresponding to the ribs ( 11 ) are also formed on the obverse side of the wall of the lining ( 2 ), hollowed troughs opposed to the stopper members ( 22 ) are formed on the reverse side of the wall of the lining ( 2 ), the hollowed troughs are suitable for matching up and receiving the vertical rib ( 11 ). as shown in fig6 , look down on the cup ( 1 ), and the lining ( 2 ), a facet ( 111 ) of the rib ( 11 ) and a facet ( 221 ) of the stopper members ( 22 ) can be formed as perpendicular spoilers which dampen vibration of the vegetable and fruit fibers ( as shown in fig7 ) but sweep them in the whirlpool ( 4 ) as much as possible to the center thereof ; and then to the lower half portion of the cup ( 1 ) being crumbled by the straight blades . but only a few rough and long fibers ( 41 ) are forced into the center of the whirlpool , most of them still left outside the inner circle of the whirlpool ( 4 ). as shown in fig7 , when the straight blades ( not shown ) is rotated in high speed , rough and long fibers ( 41 ) in the whirlpool ( 4 ) remained in the teeth ( 21 ) on the surrounding inner wall of the lining ( 2 ) will soon be grated and chopped into pieces . possibility of the rough and long fibers being grated is greatly improved . though the fibers all are not easily forced into the whirlpool center at once , they can be chopped into pieces by the teeth ( 21 ) as well . therefore , the duration for the blender stirring the chopped fibers is reduced ; meanwhile , possibility of oxidization of the stirred juice is also reduced . rather , the top end of the stopper members ( 22 ) has a number of teeth ( 21 ′) projected up thereof , by means of the projected teeth ( 21 ′), the fibers of vegetable and fruit can be further grated and chopped into pieces . the teeth ( 21 ′) projected up from the top end of the stopper members ( 22 ) are advantageous to the grinding . as shown in fig8 , the container of the blender includes a cup ( 1 ), and a rigid lining ( 2 ) mounted inside the cup ( 1 ). first , each of the cup ( 1 ) and lining ( 2 ) are prefabricated components , and then the lining ( 2 ) is mounted inside the cup ( 1 ) and combined to the cup ( 1 ) integrally as a whole . after combination , the assembled view of the container is illustrated as shown in fig9 . the lining ( 2 ) is shaped as a half - mask . but several prop stands ( 23 ) extended from the top rim of the hood ( 2 ) to a height adjacent to the top rim of the cup ( 1 ), a horizontal ring ( 24 ) is connected to the top ends of the prop stands ( 23 ). the horizontal ring ( 24 ) is convenient for the users to hold , and when the lining ( 2 ) is mounted inside the cup ( 1 ), the horizontal ring ( 24 ) placed on the l - shape ( i . e . like a top step of a ladder ) top rim of the container which is suitable for a lid ( not shown ) capped over the container , then the horizontal ring ( 24 ) is sandwiched between the container and the lid . therefore the lining ( 2 ) can be mounted inside the container without any movements . as shown in fig1 , the container of the blender includes a cup ( 1 ), and a rigid lining ( 2 ) mounted inside the cup ( 1 ). the cup ( 1 ) and the lining ( 2 ) are prefabricated separately , and then the lining ( 2 ) is embedded into the cup ( 1 ) and combined to the cup ( 1 ) integrally as a whole . after combination , the assembled view is illustrated as shown in fig1 . the lining ( 2 ) is shaped as a half mask , which is composed of a number of lining pieces ( 2 a ). a stopper member ( 22 ) is formed on the obverse side of the lining piece ( 2 a ) as well as the teeth ( 21 ) are arrayed on the same side . the first facet of the stopper member ( 22 ) is bended inward to form a buckled piece ( 222 ). a groove ( 113 ) is defined on the first facet of the rib ( 11 ) of the cup ( 1 ), the buckled piece ( 222 ) can be led into the groove ( 113 ) in place and then the rib ( 11 ) enclosed inside the hollowed trough formed on the reverse side of the stopper member ( 22 ). the second facet of the lining pieces ( 22 ) is a flat facet directly leads into a trench ( 112 ) defined on the second facet of the rib ( 11 ) of the cup ( 1 ). a number of teeth ( 21 ′) can also be arranged on the top end of stopper member ( 22 ). rather , the lip ( 26 ) is extended radially outwardly from the top rim of the lining pieces ( 2 a ) is convenient for the user to hold when the lining pieces ( 2 a ) are assembled or disassembled with each other . as shown in fig1 , the container of the blender includes a cup ( 1 ), and a rigid lining ( 2 ) mounted inside the cup ( 1 ). the cup ( 1 ) and the lining ( 2 ) are prefabricated components . the lining ( 2 ) is embedded into the cup ( 1 ) and then combined to the cup ( 1 ) integrally as a whole . after combination , the assembled view is illustrated as shown in fig1 . the lining ( 2 ) is shaped as a whole mask . the lining ( 2 ) is composed of a number of lining pieces ( 2 b ), but the top rim of the lining ( 2 ) is bended outward to form a horizontal ring ( 27 ). the horizontal ring ( 27 ) is not only convenient for the user to hold to assemble or disassemble the lining pieces ( 2 b ), but the horizontal ring ( 27 ) can be placed on the top step of the ladder like top rim of the container so as the horizontal ring ( 27 ) can be sandwiched between the cup ( 1 ) and the lid ( not shown ) without any movements .

the present invention is aimed to provide a container of the blender . it can prevent the inner wall of the container from abrasions and blemishes . further , the time - consuming for fibers of the fruit and vegetable being grated and chopped can be reduced . the container of the blender includes a cup , a lining mounted inside the cup characterized in that the lining as a shield screen on the inner wall of the cup , the inner wall of the lining has a number of teeth projected thereof for grating the fibers of the vegetable and fruit .

the catheter comprises a calibrator oval 10 , a flexible shaft 12 , a manifold 14 which serves for the connection of a syringe 16 to the instrument , a balloon 18 which is longitudinally extensible from the oval 10 under the fluid pressure applied by syringe 16 and thereafter laterally expansible under increased fluid pressure , and a guide wire 20 to be pulled to re - invert the balloon 18 within the oval 10 . a blood vessel 22 partially occluded by occlusion 24 is provided with an incision 26 for the introduction into the vessel of the catheter . the catheter is moved along the vessel until the oval 10 bears against the end of occlusion 24 , as shown in fig1 . the syringe 16 is then attached to manifold 14 and actuated to evert the balloon 18 and extend it into the restricted lumen of occlusion 24 . the fluid pressure is then increased to radially expand the balloon and compress the occlusion . the fluid pressure is then reduced by reverse operation of the syringe and the syringe is removed from manifold 14 . wire 20 is then manually pulled to re - invert the balloon within the oval . the oval is then moved within the compressed occlusion 24 . ready movability of the oval through the occlusion indicates that the occlusion has been adequately compressed . if the oval is not readily movable through the occlusion the instrument is used to further compress the occlusion . once the occlusion has been suitably compressed the instrument may be moved further along the vessel 22 , as indicated in fig4 if there is a further occlusion to be treated . the details of construction of the instrument are shown in fig5 - 6 . the oval 10 and shaft 12 are formed by a tightly wound helical spring 28 which provides the catheter with sufficient flexibility to enable its movement through tortuous arteries . the oval and shaft are provided with an overcoating 30 of silicone , heat - shrink tubing , teflon , or the like . the balloon element 18 is made of an elastomeric material such as latex . one end of the balloon is attached to the end of the oval 10 and the other end of the balloon is attached with suture 32 to guide wire 20 . the wire 20 is small in diameter relative to the internal diameter of spring 28 to provide an annular fluid passage between the syringe 16 and balloon 18 . expansion of the balloon element out of the end of the catheter takes place in anisotropic fashion , with the balloon element first everting out of the catheter in advance of substantial lateral expansion , and then , after eversion , laterally expanding in response to the continued exertion of fluid pressure internally of the catheter . optimal dimensional data for the catheter and the balloon element are set forth in my co - pending application ser . no . 060 , 408 . while the invert - evert form of balloon is preferred , other types and forms of balloons may be used as long as they do not impede the movability of the catheters through the arteries and as long as they do not interfere with the use of the calibrator ovals to measure or calibrate the inside diameters of the arterial lumens .

a catheter is provided with an inflatable - deflatable balloon element to radially enlarge a partially occluded artery lumen and the catheter is provided with a calibrator oval to internally gauge the enlarged lumen .

turning now to the drawings wherein several preferred embodiments of the invention are shown , in fig1 , a conventional , well known agricultural cutting machine , which is a combine 20 , is shown including a header 22 . header 22 is shown supported in the conventional , well - known manner on a forward end 24 of combine 20 , and is operable for cutting or severing crops such as , but not limited to , small grains such as wheat and soybeans , and inducting the severed crops into a feeder 26 for conveyance into combine 20 for threshing and cleaning , in the well known manner , as combine 20 moves forwardly over a field , as denoted by arrow f . referring also to fig2 , which is a side view of header 22 , header 22 includes a pan or floor 28 which is supported in desired proximity to the surface of the field during the harvesting operation , and an elongate , sidewardly extending sickle 30 along a forward edge portion 32 of floor 28 , sickle 30 being operable for severing the crop for induction into header 22 , as will be explained . header 22 additionally includes an elongate , sidewardly extending reel 34 ( shown in outline form in fig1 ) disposed above sickle 30 and rotatable in a direction for facilitating induction of the severed crops into header 22 . an elongate , rotatable auger 36 ( also shown in outline form in fig1 ) that extends in close proximity to a top surface 38 of floor 28 and has helical flights therearound is operable in cooperation with reel 34 for conveying the severed crops toward an inlet opening of feeder 26 for induction into combine 20 , in the well - known manner . referring more particularly to fig1 , sickle 30 extends in a sideward direction along the width of floor 28 , between a first side edge portion 40 of the floor , and an opposite second side edge portion 42 . sickle 30 includes an elongate , sidewardly extending cutter bar assembly 44 supported in substantially longitudinally aligned relation adjacent to forward edge portion 32 of floor 28 , along the length thereof . referring also to fig3 , 4 and 5 , cutter bar assembly 44 includes a plurality of forwardly extending , elongate guards 46 arranged in a sidewardly extending , spaced apart array , along the forward edge portion of header 22 . each guard 46 is preferably of cast metal and includes a rearwardly located base 48 , which is suitably attached , here by a bolt 50 and a nut 52 , to a fixed bar 54 or other fixed structure of assembly 44 . here , it can be observed that guards 46 are provided in pairs connected together by a crossmember , although it should be understood that , alternatively , they could be provided individually , or connected together in a greater number , with equal utility for the purposes of the present invention . each guard 46 additionally includes a forwardly extending finger 56 attached to base 54 , finger 56 having a forwardly located forward tip 58 . each finger 56 includes oppositely facing side surfaces 60 and 62 which extend forwardly from adjacent base 48 to tip 58 , and which taper convergingly as they approach tip 58 . each finger 56 also includes an upwardly facing surface 64 which extends from base 48 to tip 58 . each finger 56 includes a slot 66 extending therethrough between side surfaces 60 and 62 , intermediate base 48 and tip 58 , slots 66 of the respective fingers 56 being aligned along the length of sickle 30 . referring more particularly to fig2 and 5 , cutter bar assembly 44 supports an elongate sickle knife 68 for reciprocating longitudinal movement within slots 66 , knife 68 including a row of knife sections 70 including oppositely facing , angularly related knife edges 72 which , in conjunction with site surface 60 or 62 of adjacent guards 50 , respectively , effect a shearing or cutting action which severs plant stems and stalks or other material captured between the knives and the guards as the knife sections are reciprocatingly moved sidewardly , as denoted by arrow a in fig5 . guards 46 will typically extend beyond sickle knife 68 by no more than 12 inches , as it may be desired under some conditions to have a capability to point the guards downwardly at a small acute angle to the ground , for instance , with the sickle close to the ground , for harvesting downed crops , without the guard tips entering the ground . it is also desirable for the guards to have a smooth streamlined shape , which is relatively narrow , so as to smoothly guide the crops into the spaces therebetween , for cutting . as noted above under the background art heading , as combine 20 is moved forwardly over a field containing crops , sickle knife 68 will be moved reciprocatingly sidewardly relative to guards 46 , to sever the crops which enter the spaces between guards 46 . knife edges 72 will capture and cut the stems or stalks of the crop plants against the side surface 60 or 62 of the adjacent guard , in an area denoted as a cutting zone 74 illustrated in relation to the leftmost guard 46 in fig5 . as a result of the cutting action , and particularly if the crop is dry and / or knife edges 72 are dull , and / or the side edge of the slot is worn and rounded , and also as a result of being batted by reel 34 , grain can be loosened from the crop plants , e . g ., pods shattered , such that the loose grain will fall onto sickle 30 , and onto any plant material thereon , so as to be in danger of falling to the ground and being lost . grain can also be shaken loose if the guards are large , or are not sufficiently streamlined for smooth crop flow therepast , or have obstructions that extend into the crop flow path , so as to shake or jar the crops as they are inducted into the sickle . this can be particularly problematic in drilled crops which lack defined rows and thus increase the possibility of guards 46 being propelled directly into plants during the cutting operation . referring more particularly to fig2 , loose soybeans 76 are depicted in the area above sickle 30 , as would be typically present during the harvesting of crops such as soybeans or other legumes , as well as other small grains . if not captured , at least some of loose grains 76 would typically be lost , for instance by falling through the spaces between knife sections 70 and guards 46 , or by falling forwardly over the front edge of the sickle . to avoid or reduce the occurrence of grain loss in the above described manner , an air discharge system 78 is incorporated into some and preferably all of guards 46 of sickle 30 , according to the present invention . air discharge system 78 includes at least one rearwardly facing air discharge nozzle 80 incorporated into upwardly facing surface 64 of each finger 56 , and an air flow passage 82 extending internally through each finger 56 from an air inlet 84 located adjacent to base 48 , to nozzle 80 , for delivering a flow of pressurized air thereto . the pressurized air is provided by a suitable source thereof , such as , but not limited to , an air pump or air compressor 86 disposed at a suitable location , such as on header 22 , and which is suitably powered , for instance , by a fluid motor , belt , shaft , chain , or the like , in the well - known manner . compressor 86 is connected to air inlets 84 , for delivering pressurized air thereto , via an air distribution system which will preferably include a main air manifold 88 extending sidewardly beneath floor 28 of header 22 , and including a plurality of nipples or small air distribution tubes 90 emanating therefrom at appropriately spaced locations therealong corresponding to the locations of air inlets 84 . smaller air distribution tubes 90 are shown extending from manifold 88 individually to air inlets 84 . alternatively , it should be recognized that a variety of different air distribution system configurations can be utilized according to the present invention . the configuration and location of air discharge nozzles 80 on surfaces 64 of respective fingers 56 can be varied according to the preferences and / or requirements for a particular application . generally , it will be an objective of the invention for nozzles 80 to be minimally if at all obstructive to crop and plant flow over and passed fingers 56 , such that little or no resultant additional jarring or disturbing of the plants passing over the nozzle occurs so as to result in additional loosening of grain from the plants . additionally according to the invention , an objective will be to generate rearwardly directed pressurized air flows that will be effective in blowing and directing loose grain on to floor 28 to capture the loose grain and prevent loss thereof . further according to the invention , it will be an objective to minimize susceptibility of plugging of nozzles 80 by plant material and the like . still further , it will be an objective when incorporating nozzles 80 and air flow passages 82 into fingers 56 , to maintain and not significantly degrade the structural integrity of the fingers , or to materially change the operability thereof . in accordance with the above objectives , several embodiments of nozzle configurations of the invention are illustrated in fig2 through 9 . referring more particularly to fig2 , 4 , 5 , and 7 through 9 , nozzles 80 are illustrated as rearwardly directed and recessed into upwardly facing surface 64 of fingers 56 . of these , nozzles 80 of fig2 , 4 , 5 and 8 are circular shaped , and nozzles 80 of fig8 and 9 are diamond shaped . this represents a range of acceptable nozzles and is thus not intended to be limiting . each nozzle 80 is also illustrated disposed at a forward end of a rearwardly extending recessed channel 92 , which , in cooperation with the nozzle configuration , facilitates and guides the pressurized air flow in a desired pattern , without significantly disrupting crop flow over upwardly facing surface 64 of the finger . however , it should be noted that other locations , including a more forward location , can be utilized according to the invention . referring more particularly to fig2 , the pressurized air flow , denoted by arrows 94 , is illustrated as flowing along a relatively low , rearwardly directed trajectory over sickle 30 and forward edge portion 32 of floor 28 . referring in particular also to fig5 , fig5 and 6 , air flow 94 is also illustrated from the side in fig8 . here , it should be recognized that the configuration , including , but not limited to , size , shape , and angular orientation , of nozzles 80 can be determined for a particular application , as can the configuration , e . g ., size , shape and angular orientation of the channel 92 if used . fig5 illustrates possible air flow patterns that can be achieved with the nozzles of the invention , including a narrower pattern that generally extends over the base region of the guard in which the nozzle is located , as defined by lines 96 emanating from the respective nozzles , and a wider fan shape pattern that extends over a greater portion of the sickle knives also , as defined generally be lines 98 . referring in particular to fig3 , a nozzle 80 which is substantially flush with surface 64 is shown , the nozzle having a generally oval or tear drop sectional shape when viewed from above . again , this illustrates the variety of nozzle configurations that can be used according to the invention . referring more particularly to fig6 , still another nozzle configuration is illustrated , which is a multiple nozzle arrangement including an array of three nozzles 80 disposed in surface 64 , facing in slightly offset directions , and configured to discharge streams of pressurized air in a wide ranging fan pattern , illustrated again by lines 98 emanating from each of the nozzles . here , it should be noted that the number of nozzles , positions , and orientations , on a finger can be varied , as desired or required for a particular application . in the fore and aft direction , nozzles 80 are preferably disposed so as to most advantageously direct the pressurized air for recovering or protecting from the loss of loose grain , without degrading the integrity and strength of the fingers . in the embodiments shown , nozzles 80 are generally located above a forward region of slot 66 through which the sickle knife reciprocates . to achieve this location , air flow passage 82 has a generally v shape , including a lower portion 100 which is routed forwardly through the finger below slot 66 , and an upper portion 102 which connects with lower portion 100 and extends rearwardly therefrom to the nozzle , or nozzles , as variously shown in the figs . air flow passage 82 can be cast in place in the finger . essentially , the fore and aft location selected here has been found to be advantageous as it places the nozzles close to the cutting zone where the largest portion of the loose grain has been typically found to be present , such that the air will be at its greatest pressure where the grain is found , and will be less likely to be dissipated by intervening plant material such as leaves , stems and the like which will be passing through the cutting zone also . it will be understood that changes in the details , materials , steps , and arrangements of parts which have been described and illustrated to explain the nature of the invention will occur to and may be made by those skilled in the art upon a reading of this disclosure within the principles and scope of the invention . the foregoing description illustrates the preferred embodiment of the invention ; however , concepts , as based upon the description , may be employed in other embodiments without departing from the scope of the invention . accordingly , the following claims are intended to protect the invention broadly as well as in the specific form shown .

a guard for a sickle of an agricultural plant cutting machine includes a forwardly extending finger including a longitudinally extending , upwardly facing surface extending over the sickle , which includes a rearwardly facing air discharge nozzle therein located above and / or forwardly of the sickle , and the finger includes an air flow passage extending internally therethrough from an air inlet adjacent to a base of the finger to the nozzle , for delivering a flow of pressurized air thereto , the nozzle being at least mostly flush with or recessed into the upwardly facing surface . as a result , the nozzle is operable for discharging the flow of air rearwardly over the finger without obstructing plant material flow thereover , the air flow being sufficient to blow at least a substantial amount of loose grain and other plant material located forwardly of the front edge of a header floor of the machine , onto the floor for collection by a conveyor of the header for processing .

referring now to the drawings , and particularly to fig1 a two - level storage and display rack , adapted for mounting on a store counter , is shown generally at 10 . the storage rack shown in fig1 has only two tiers , but more tiers may be provided using vertical spacers , as shown in fig3 and 5 , to space the additional tiers apart . each shelf , or tier , of the two - tiered display rack example of fig1 may be provided of a size , to have supported thereon , the goods - containing portion of a box of counter goods , such as chocolate bars , chewing gum , or other goods that the store keeper may be offering for sale . a five - tiered rack , using structural elements as disclosed hereinafter , has been constructed and has been demonstrated to be of stable construction . the horizontally elongated shelf of the lowermost tier of display rack 10 is generally indicated by numeral 12 , with an upper , second , horizontally elongated tier shelf 14 spaced above said lowermost tier shelf 12 . each of the tier shelves 12 and 14 has associated , elongated , edge rails that are similarly constructed , so that a detailed description of the edge rail elements , and other features of construction of the lower tier shelf 12 will operate to provide a description of similar elements shown associated with the second tier shelf 14 . some elements , such as the specific vertical , columnar , side spacers 16 , that are positioned to extend between side rails associated with the two shelves 12 and 14 are shown assembled only in fig1 - 3 , in position on vertically aligned side rails to serve as a spacer and a support . the exploded view of fig5 illustrates how these vertical spacers may be used either above or below a tier that includes one horizontal tier shelf for supporting another tier shelf , and these spacers may , for example , be used below the tier shelf 12 shown in fig5 or between a pair of tier shelves 12 and 14 , to serve to either support the lowermost tier above a counter , or to space a next higher tier above a next lower tier . in the specific illustrations in the figures , the lower tier includes a flat , planar , horizontal support shelf member 12 . the forwardmost end of shelf member 12 is provided with a transverse abutment wall 20 that lies in a plane transverse to the plane of shelf member 12 , and is secured to shelf member 18 by any means , such as by being glued or melded thereto . the portion of the transverse , forward abutment wall 20 that extends above the upper surface of shelf 12 , is positioned to serve as an abutment against which a wall of a body , or box , that is supported on shelf 12 may abut . the rear end of the storage and display rack 10 , that is opposite forward wall 20 , is open , so that an attendant may easily withdraw an empty box supported on the shelf 12 , and insert onto the shelf 12 , from rearwardly of the rack 10 , a fresh , or replacement , box with goods therein . the lower tier shelf 12 is provided , along each of its longitudinal edges , with associated , elongated , upper and lower rail members , respectively 22 and 24 , whose assembled structural portions are best seen in fig1 - 4 , and whose overall shape may be seen in perspective in fig5 . an upper rail member 22 , located adjacent to the left edge of shelf member 12 , as viewed in fig1 and 3 , includes an elongated , upper side rail , or body , that is provided with an elongated upwardly - opening groove means 25 in the upper edge of rail member 22 that is bounded by spaced , upright , inner and outer , longitudinal side walls , 28 and 30 , that are spaced by transverse end walls 32 and 33 . the upper side rail along the right hand longitudinal edge of shelf 12 is of similar construction and is designated 22 &# 39 ;, and with the parts thereof using the same identifying numeral with a prime (&# 39 ;) mark . as seen in fig3 when a shelf , such as shelf 12 , and its side rails are assembled , only a portion of the total height of upper rails 22 and 22 &# 39 ; extend above the upper surface of shelf 12 . the lower rails 24 and 24 &# 39 ; each are of mirror image construction relative to its adjacent upper side rails 22 and 22 &# 39 ;. but while upper rails 22 and 22 &# 39 ; have only portions thereof located vertically above the plane of adjacent shelf 12 , the lower edge rails 24 and 24 &# 39 ; have all portions thereof located below the plane of shelf 12 . the lower edge rails 24 and 24 &# 39 ; each also include a downwardly opening elongated recess or groove 27 that is located in a mirror - image relation to the similar structures provided in upper rails 22 and 22 &# 39 ;, but as seen in fig3 all portions of lower side rails 24 and 24 &# 39 ; are located below the plane in which shelf 18 is located . one purpose of having a pair of laterally spaced upper rails 22 located adjacent the two longitudinal edges of shelf 12 is to provide a pair of longitudinal elements that may be moved toward or away from each other to engage , or accommodate , the width of the box that rests on shelf 12 , where the box is at least as wide as , or or wider than , the shelf 12 . if the width of a rectangular box on shelf 12 is less than the width of shelf 12 , then , at most , only one side wall of the box might be engaged by the innermost side of one of the two upper rails 22 or 22 &# 39 ;. since each of the two upper rails 22 and 22 &# 39 ; are mirror images of each other , the similar elements on rail 22 &# 39 ; carry the same identifying numeral as appears on rail 22 , but with a prime mark (&# 39 ;) added . it will now be seen , from fig1 and 5 together , that the upper and lower rail members adjacent the side edges of shelf 12 have an exterior shape that is essentially the same . it will be understood that , if desired or necessary , the rail members themselves may be provided with selected interior shapes and walls for receiving and cooperating with spacer members of different size as may be necessary , or desired . however , for purposes of the description herein , it is to be understood that all rail members will be fundamentally of the same shape and size , except as may be needed to provide a modification . fig1 and 3 illustrate how a pair of upper , side rail members , 22 and 22 &# 39 ;, are each assembled alongside the two longitudinal edges of both lower shelf 12 and upper shelf 14 . the underside of each shelf , 12 and 14 , includes the same structure as shown on the underside of shelf 22 in the exploded perspective view of fig5 . thus , the underside of each tier shelf , 12 and 14 , is provided with two pairs of spaced angle sections 26a and 26b that are secured , or otherwise adhered to , or melded with , the undersurface of said shelves to make an integral structure adjacent each of the two lateral edges of the shelf . also , and so that shelf 12 will not tilt , or slope , from front to back , the rear end of shelf 12 is provided with a rail 20 &# 39 ;, seen in exploded fig5 which extends below shelf 12 the same distance that the lower portion 20a , of transverse abutment wall 20 , extends below shelf 12 . as best seen in fig5 a shelf , such as either the planar support shelf 12 or 14 , has affixed to the underside thereof , such as by gluing , or melding , two sets of socket angle sections , 26a and 26b , that lie respectively adjacent the lateral shelf edges 12a and 12b . although aligned sets of separated socket angle sections 26a and 26b are shown , elongated angle - shaped sections , of the cross - section seen in fig4 could be used instead , and then the end portions of said elongated sections would be the equivalent of the structures shown . the said socket angle sections , together with the underside of the shelf 12 to which the socket angle sections attach , provide generally socket - like , or generally rectangular , tubular - like , sockets , or tongue - holding means , indicated at 26c , for slidably receiving thereinto , or therethrough , lateral extensions , or tongues , 22a and 22b , that extend from an upper rail 22 . the same sockets , or tongue - holding means , also receive lateral extensions 24a and 24b that extend from a lower rail 24 , as is seen in fig3 . as best seen in fig3 when a shelf 12 or 14 has its rails 22 or 24 assembled thereon , the socket angle sections 26a and 26b are of a size and spacing from the underside of the associated shelf 12 , so that the two adjacent tongues , 22a and 24a , or 22 &# 39 ; a and 24 &# 39 ; a , of the two rails 22 and 24 are held by the tongue - holding means against the undersurface of a planar support , such as 12 or 14 , in each socket space 26c provided between spaced , angled , flange sections 26a and 26b . the cross - sectional view of fig3 shows the upper rails 22 and 22 &# 39 ;, when moved to their closest spacing , which is controlled or dictated , by the fact that upper rails 22 and 22 &# 39 ;, as seen in fig1 and 3 , abut opposite lateral edges of shelf 12 , with rail 22 abutting shelf edge 12a while rail 22 &# 39 ; abuts an opposite shelf edge 12b , as seen in fig3 . the lower rails 24 and 24 &# 39 ; are not so constrained , but lower rails 24 and 24 &# 39 ;, are preferably to be selectively moved into a position of vertical alignment with a set of upper rails 22 and 22 &# 39 ;, as best seen in fig1 . alternatively , lower rails 24 and 24 &# 39 ;, may be selectively moved laterally inwardly until said rails abut the edges of angle flange sections 26a and 26b , or may be moved laterally outwardly of the position shown in fig3 provided that some portion of tongues 24a and 24 &# 39 ; a are not moved outwardly to a position where all portions of tongues 24a and 24 &# 39 ; a escape the tongue holding means provided by socket angle sections 26a and / or 26b . considering the structure shown in fig3 the lower rails , 24 and 24 &# 39 ;, could be moved inwardly toward each other until an innermost portion of those rails abut an edge of the socket angle sections 26a and 26b . referring now to the manner of effecting selective vertical spacing between the support shelves 12 and 14 , or between shelf 12 and the top of a counter upon which the tiered display of fig1 is supported , or between upper shelf 14 and a third shelf thereabove , the means for effecting such spacing utilizes the fact that each rail member 22 , 24 , 22 &# 39 ; and 24 &# 39 ; is provided with an interior groove means , such as the upwardly opening groove means 26 of rail 22 , that is bounded longitudinally , such as by side walls 28 and 30 as described above , and as seen in fig1 - 3 and 5 . more specifically , the groove means 26 does not provide a continuous slot along the length of its rail . instead , each rail , such as rail 22 seen in fig2 and 4 , and rail 24 as seen in fig3 and 5 , includes , in the groove means for the rail , one or more transverse ribs such as 40 and 42 , that are clearly shown in fig2 . to cooperate with such groove means and its transverse ribs 40 and / or 42 , there are provided vertical spacers , or columnar spacer means , in the form of planar , spacer plates 16 , referred to earlier above . these planar spacer plates 16 are of a thickness to slidably fit into the longitundinal space between spaced side walls 28 and 30 of a rail member 22 or 24 . within the longitundinal space between the spaced side walls 28 and 30 of the rail member , there are provided one or more transverse ribs 40 and 42 as seen in fig2 . the shape of spacer plates 16 are most clearly seen in fig1 and 5 . spacer plates 16 are rectangular in elevation as seen in fig5 with their length edges 46 being greater than their height edges 48 . as will appear from the following description , the rectangular spacer plates provide for two alternative spacings between shelves 12 and 14 . a pair of opposed notches , 44 , extending from the length edges of spacer plate 16 , are provided in alignment with each other and extend toward each other from the long edges 46 of the rectangular plate 16 . the length of the short edges 48 and 48 &# 39 ; of plate 16 provides an effective measure of one spacing between an aligned upper rail 22 , associated with lower shelf 12 , and a lower rail 24 , associated with upper shelf 14 , spaced thereabove as seen in fig1 . the notches 44 are of a size and shape to permit a spacer plate 16 to fit over a transverse rib 40 or 42 , here shown , in fig2 to be rectangular in cross section . the spacing of notch 44 from the distal short edge 48 &# 39 ; is selected so that when a notch 44 receives therein a rib 40 , as seen in fig2 the distal short edge 48 &# 39 ; of plate 16 will slide against , and engage the closest edge 42 &# 39 ; of rib 42 , as shown in fig2 . similar ribs provided in an opposite rail member , such as rail members 24 or 24 &# 39 ; ( seen in fig5 ) permits the spacer plate to provide for firm engagement and interconnection between a pair of oppositely facing rail members , such as between one lower rail 22 and an opposed upper rail 24 , as seen in fig1 . if a greater spacing is desired between a pair of shelves 12 and 14 , the spacer plates 16 are to be rotated ninety degrees ( 90 °) from their length position seen in fig1 to a width position where edges 48 and 48 &# 39 ; take the positions shown for long edges 46 as seen in fig5 . the length of edges 48 and 48 &# 39 ; are selected so that long edges 46 of a spacer plate 16 will slidingly fit between ribs 40 and 42 . in this latter arrangement , since a shorter edge of spacer plate 16 is captured in a groove , the spacing between a pair of spaced shelves 12 and 14 will be greater . the spacer plates may also be used as a pair of free legs to support lower rail members 24 and 24 &# 39 ; upon the surface of a flat counter , as suggested by the lower truncated spacer plates shown extending downwardly in fig3 . by inclining , or beveling the lower edges , of a pair of laterally spaced support legs extending downwardly from lower rail members 24 and 24 &# 39 ;, the tiered display stand may be converted to a stand wherein the goods supported thereon are displayed at an inclined attitude , with the goods on a shelf , such as shelf 12 , engaging the upper front flange 20 located at the forward end of a support shelf plate 12 or 14 . the material used in making the various parts shown in the figures of the drawings are a transparent plastic , thereby creating a tiered display stand that is eye - catching and attractive , while at the same time providing the rigidity and strength needed to serve the purpose as a display stand . the nature of the plastic material permits ease in forming and assembly , yet provides for inexpensiveness of construction and strength for the intended purposes . while a particular embodiment of this invention has been shown and described , it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention and , therefore , it is intended in the appended claims to cover all such changes and modifications which fall within the true spirit and scope of the invention .

a variable width tiered display stand , which may be supplied in knocked - down condition , and which may be readily assembled at the site of use , is disclosed . the stand provides multiple tiers , each adapted for support of a box of boxed goods thereon , to provide an attractive means for display , and offer , of goods to prospective customers , while permitting the shopkeeper to easily withdraw empty boxes of goods from the tiers and to insert fresh boxed goods on the tiers as may be required or desired . the stands are preferably made of transparent plastic parts which may be easily fit together , and which do not require additional fastener means for keeping the tiered display stand assembled .