Abstract:
An instrument for applying clips in surgery having an operating handle with operating components and a clip cartridge with clip applying mechanism. The handle operating components generate reciprocal linear motion imparted to the clip applying mechanism and accommodate rotation of the cartridge about a cartridge axis. An anti-backup mechanism constrains operating components to complete first and second strokes of reciprocal linear motion.

Description:
PRIOR APPLICATION  
       [0001]     This application is a division of U.S. patent application Ser. No. 10/315,969 filed Dec. 10, 2002, now abandoned. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The present invention relates to surgical clip appliers embodied as an instrument having a supply of clips for rapidly deploying several clips in closing severed blood vessels and other small fluid carrying ducts in surgical procedures. There are many different designs for surgical clip applicators for a variety of surgical procedures including both open surgery and laparoscopy in which a clipping appliance fits through a trocar tube into a body cavity where the clips are applied.  
         [0003]     A surgical clip applicator comprises an operating handle and clip applying mechanism having an operating cycle in which operating levers are squeezed together and released. In this operating cycle, a clip is applied in surgery and the clip applicator jaws are reloaded with a single clip from a clip supply channel for clip application in the next cycle. The applicator provides a moveable clip supply channel containing a line of clips that are released seriatim. The supply channel integrates a clip pusher and an escapement or clip stop spring in a single unit.  
         [0004]     A well-known hazard with clip appliers is a condition of releasing a partially closed clip in a surgical site. This condition results when operating handles are given a partial pull or closing and then released. The partial pull crimps but does not close a clip located in the instrument jaws. When partially pulled handles of some older instruments are released, the instrument jaws re-open and the partially closed clip falls from the jaws into the surgical site.  
         [0005]     This invention provides an anti-backup mechanism for a repeating multi-clip applier to prevent this operating hazard.  
       SUMMARY OF THE INVENTION  
       [0006]     A preferred embodiment of repeating multi-clip applier according to the present invention comprises an instrument having an operating handle housing and a removable, fully rotatable and disposable clip applying cartridge. A full squeeze and release of operating handles applies a clip to a surgical site and reloads another clip into clip applying jaws of the instrument.  
         [0007]     The operating handle housing accommodates an anti-backup mechanism to prevent a partial pull and release of the operating handles to prevent the hazard of a partially closed clip falling into the surgical site. The present invention prevents occurrence of this condition by means of an anti-backup mechanism to ensure that when the appliance handles are pulled, the handles must be given a full pull to execute a complete cycle of the clip applier mechanism. If a partial pull of the appliance handles occurs, the anti-backup mechanism retains or holds the clip applier mechanism in fixed position without possibility of backup or reverse. The anti-backup “hold” is released simply by giving the handles a complete pull. When a partial pull occurs and the anti-backup mechanism holds the clip applying mechanism in place, the instrument jaws remain partially closed holding a partially closed clip thereby preventing the clip from falling into a surgical site. The anti-backup mechanism also functions in the opposite, or release, motion of operating handles. That is, the operating handles when being released are constrained by the anti-backup mechanism to undergo a full release motion. The anti-backup mechanism prevents partial release and re-pull of the trigger thereby to prevent double loading of a clip into the crimping jaws, a condition that would jam the instrument.  
         [0008]     Specific examples are included in the following description for purposes of clarity, but various details can be changed within the scope of the present invention.  
       OBJECTS OF THE INVENTION  
       [0009]     An object of the invention is to provide a clip applicator having an operating handle that provides anti-backup linear reciprocating motion of a clip applying cartridge.  
         [0010]     Another object of the invention is to provide a clip applicator having an operating handle with an anti-backup mechanism that permits full forward and reverse strokes of a clip applying cartridge to avoid the hazard of releasing a partially crimped clip at a surgical site.  
         [0011]     Another object of the invention is to provide a clip applicator having an operating handle with an anti-backup mechanism that permits full forward and reverse strokes of a clip applying cartridge to prevent double loading of a clip into the crimping jaws, a condition that would jam the instrument.  
         [0012]     Other and further objects of the invention will become apparent with an understanding of the following detailed description of the invention or upon employment of the invention in practice. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0013]     A preferred embodiment of the invention has been chosen for detailed description to enable those having ordinary skill in the art to which the invention appertains to readily understand how to construct and use the invention and is shown in the accompanying drawing in which:  
         [0014]      FIG. 1  is a side elevation view of the applicator of  FIG. 1  with the operating handle housing partially in section and with handles in release position.  
         [0015]      FIG. 2  is a side elevation view of the applicator of  FIG. 1  with the operating handle housing partially in section and with handles in pull position.  
         [0016]      FIG. 3  is a side elevation of a rotary translator.  
         [0017]      FIG. 4   a  is a side elevation view of the rotary drum.  
         [0018]      FIG. 4   b  is a longitudinal section view of the rotary drum of  FIG. 4   a.    
         [0019]      FIG. 5  is a front elevation of anti-backup disc.  
         [0020]      FIGS. 6    a - g  are sequential views of anti-backup mechanism with disc in (a) rear groove, (b)&amp;(c) between grooves, (d) in front groove, (e)&amp;(f) between grooves, and (g) again in rear groove, and with arrows indicating directions of permitted and prevented movement of operating handle and cartridge mechanism. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0021]     Referring to the drawing, a preferred embodiment of the repeating multi-clip applier  10  comprises operating handle housing  12  and clip applicator cartridge  14 .  
         [0022]     The operating handle housing  12  shown in  FIGS. 1-2  comprises handle members including a depending grip  12   c , a center section defining a central chamber  12   e , and a forward cylindrical portion  12   f  defining a forward chamber  12   g.    
         [0023]     A trigger  18  for actuating applier mechanisms is mounted on the housing for pivotal movement about axis A-A′, normal to  FIG. 1 . The trigger includes a depending grip portion  18 .  
         [0024]     The trigger when pulled transmits motion to the clip cartridge mechanism (not shown) through the intermediation of fixed translator slide  20  and a rotary translator  22 . The trigger acts against the forward bias of bar spring  16  with its end  16   a  held by translator slide recess  20   a.    
         [0025]     The rotary translator  22  ( FIGS. 1, 2 , and  3 ) forms a subassembly with an anti-backup mechanism  24 , a rotatable drum  26 , and a thumb wheel hub  28  which subassembly interconnects the fixed translator  20  and the clip cartridge  14  for performing the functions of transmitting reciprocating rectilinear motion with a fixed excursion, accommodating rotary motion of the clip cartridge, enabling mounting and disconnecting of the clip cartridge from the operating handle, and providing an anti-backup capability for the operating handle and cartridge mechanism.  
         [0026]     The rotary drum subassembly  22 ,  24 ,  26  comprises the rotary translator  22  positioned axially within the drum  26 . An anti-backup disc  24  ( FIGS. 2, 3  and  5 ), defined by an open center  24   a  and extending radially from the center to define a plurality of inwardly directed spring fingers  24   c , fits onto the rotary translator  22  and is assembled to the enlarged rear end flange  26   h  of the rotary drum by means of a drum cap  26   i  ( FIGS. 1 and 2 ). In normal position of the clip applicator with the trigger released, the anti-backup spring fingers  24   c  are located in the rear anti-backup groove as shown in  FIG. 1 .  
         [0027]     The rotary drum subassembly is assembled into the forward chamber  12   g  of the operating handle housing. The center section  22   c  ( FIG. 3 ) of the rotary translator shaft has spaced anti-backup grooves  22   d ,  22   e  with the distance between the grooves being approximately equal to the distance of reciprocating rectilinear motion of the fixed translator and equal to the rectilinear excursion of the clip applicator mechanism.  
         [0028]     The operation of the anti-backup mechanism is illustrated in  FIGS. 6   a - g.    
         [0029]     In the mechanism position of  FIGS. 1 and 6   a , the handle trigger  18  is in released position with the anti-backup disc  24  in registry with the rear anti-backup groove  22   d  of the rotary translator  22 . When the trigger is pulled ( FIG. 2 ) (for crimping and applying a clip at a surgical site), the rotary translator moves in the direction of arrow  6   a . As the rotary translator continues movement, the spring fingers  24   c  of the disc engage the outer surface  22   c  of the rotary translator in the manner shown in  FIGS. 6   b - c . The anti-backup mechanism applied by the canted spring fingers  24   c  ( FIGS. 6   b - c ) to the outer surface  22   c  of the rotary translator permits continued movement in the direction of arrow  6   a  and prevents movement in the opposite direction of arrow  6   b . If a surgeon releases the trigger with less than a full pull stroke leaving anti-backup components in the position of  FIG. 6   c , for example, the anti-backup mechanism holds the rotary translator in position against the bias of bar spring  16  which tends to return the trigger to release position. In this  FIG. 6   c  hold position, the applicator jaws retain the partially crimped clip preventing it from falling into a surgical site. A continuing pull of the trigger (in direction of arrow  6   a ) moves the rotary translator through the position of  FIG. 6   c  to the position of  FIG. 6   d  in which the spring fingers  24   c  enter the forward groove  22   e.    
         [0030]     In this position ( FIG. 6   d ), the rotary translator may now be moved forward (by releasing the trigger and by force of return spring  16 ) in the direction of arrow  6   c . In this forward movement, the spring fingers  24   c  are effective to allow continued forward movement while preventing movement in the direction of arrow  6   e . If the handle trigger is held by a surgeon with components as in  FIG. 6   f , the anti-backup mechanism will prevent the surgeon from pulling the trigger in the direction of arrow  6   e . The surgeon must allow full release of the trigger to component position of  FIG. 6   g . Direction of movement can be changed again when the spring fingers  24   c  enter the rear groove  22   e  as in  FIG. 6   g.    
         [0031]     A pull on the trigger against the force of bar spring produces unitary rearward rectilinear movement of the fixed translator, the rotary translator passing through the stationary spring fingers of the anti-backup disc, and the puller bar emerging from within the cartridge casing until the trigger and fixed translator reach the end of travel and with the anti-backup disc spring fingers positioned at the front groove. The rearward excursion is now complete, and when the trigger is released, the bar spring urges the fixed translator forward until all components reach normal position.  
         [0032]     In the event a pull on the trigger is released without reaching the full extent of rectilinear motion, the anti-back up spring fingers will not have reached their front groove remaining instead in contact with the outer surface of the rotary translator. The spring fingers in contact with outer surface function as a brake against the action of the bar spring tending to force the released components to return to normal position. In this partial pull condition of the trigger a clip has been crimped in the instrument jaws which clip will fall out of the jaws into a surgical site if the jaws reopen by return of the mechanism to normal position. So the anti-backup mechanism retains the instrument in “partial pull position” against the normalizing force of the bar spring and most importantly prevents fallout from the jaws of a partially crimped clip. The anti-backup device retaining action is removed simply by means of a full pull on the trigger causing the spring fingers to enter the forward groove where they can go “over center” thereafter permitting the rotary translator to pass through the spring fingers. It is to be noted that the anti-backup mechanism is effective in both directions. The anti-backup mechanism has effect when the trigger is released after a full pull so that if there is a “partial release” of the trigger, the trigger must nonetheless return to normal position with full release of the trigger before allowing the trigger to be pulled. The design requirement for full release achieved by the anti-backup mechanism prevents double loading of clips into cartridge jaws.  
         [0033]     It is a further aspect of the anti-backup mechanism that the cartridge may be rotated on the B-B′ axis as the anti-backup mechanism holds the instrument in partial pull position enabling a surgeon to adjust cartridge or jaw position even after a partial pull has occurred.  
         [0034]     Various changes may be made to the structure embodying the principles of the invention. The foregoing embodiments are set forth in an illustrative and not in a limiting sense. The scope of the invention is defined by the claims appended hereto.