Abstract:
The surgical instrument includes a shaft having a distal end portion and a proximal end portion; an operative device is disposed on the distal end portion. A hand mechanism has a first handle and a second handle and is disposed on the proximal end portion. Movement of the second handle relative to the first handle actuates the operative device. A ratchet, attached to the second handle, locks the operative device and moves with the second handle. The ratchet is pivotally attached to the second handle and pivots between a locked position and an unlocked position. A biasing device biases the ratchet toward the locked position and a release mechanism for moves the ratchet from the locked position. At least one of the release mechanism and the ratchet has a feature permitting relative movement between the release mechanism and the ratchet.

Description:
[0001]     This nonprovisional application claims priority to U.S. Provisional Application No. 60/613,158, filed on Sep. 24, 2004. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     This invention relates to an endoscopic surgical instrument.  
         [0003]     A surgical instrument, such as a clamp or suture retriever, may have jaws, a handle and a ratchet. Operation of the handle opens and closes the instrument&#39;s jaws, which are used to hold tissue or retrieve a suture. The ratchet allows the jaws to be locked in position once the ratchet is engaged. Generally, these instruments have a trigger that engages and disengages the ratchet. Consequently, a surgeon using the instrument must perform a two step process to operate the ratchet. First, the jaws of the instrument are opened or closed to a desired position. Second, the ratchet is engaged to lock the jaws in this position. It is desirable to simplify operation of this type of instrument.  
         [0004]     Some devices of this type locate the trigger for actuating the ratchet on a finger loop of one of the handles. Hence, to operate the ratchet, a surgeon must move his finger from a position on the back part of the loop to the front part of the loop, where the trigger for the ratchet is located. Accordingly, the surgeon must hold his finger out to release the ratchet and then move the handles to operate the jaw. When closing the jaws of the instrument, the surgeons&#39; hand must close while one of his fingers is held out to keep the ratchet released. This movement is awkward.  
         [0005]     Also, the jaws of the instrument may have teeth to grasp tissue or a suture. However, there may be instances where it is desirable to pull on a suture without holding the suture in place. Accordingly, a need exists for a jaw that permits this freedom of movement.  
       SUMMARY OF THE INVENTION  
       [0006]     Like existing surgical instruments, the present invention has handles, a ratchet, and jaws. The handles have a first handle and a second handle that operate in a scissor-like fashion to open and close the jaws. The ratchet is used to lock the jaws at a desired position.  
         [0007]     In contrast to existing handles, the surgical instrument engages and disengages the ratchet by movement of one of the handles. Accordingly, opening of the handles opens the jaws and locks the jaws in place. Closing of the handles closes the jaws and simultaneously locks the jaws in place. Hence, the inventive instrument automatically engages and disengages the ratchet, thereby facilitating the locking and unlocking of the ratchet. In addition, the locking and unlocking of the instrument is in the same direction at the movement of the handle. Operation of the instrument is greatly facilitated.  
         [0008]     The surgical instrument includes a shaft having a distal end portion and a proximal end portion; an operative device is disposed on the distal end portion. A hand mechanism has a first handle and a second handle and is disposed on the proximal end portion. Movement of the second handle relative to the first handle actuates the operative device. A ratchet, attached to the second handle, locks the operative device and moves with the second handle. The ratchet is pivotally attached to the second handle and pivots between a locked position and an unlocked position. A biasing device biases the ratchet toward the locked position and a release mechanism for moves the ratchet from the locked position. At least one of the release mechanism and the ratchet has a feature permitting relative movement between the release mechanism and the ratchet. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]     The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows:  
         [0010]      FIG. 1  illustrates a view of the surgical instrument, including handle assembly, ratchet assembly and jaw assembly.  
         [0011]      FIG. 2  illustrates an exposed cross-section of the instrument of  FIG. 1 , highlighting the features of the handle assembly, ratchet assembly and jaw assembly.  
         [0012]      FIG. 3  illustrates a close up view of the jaw assembly of  FIG. 2  with first jaw portion and second jaw portion closed to form an eyelet.  
         [0013]      FIG. 4  illustrates an exploded view of one of the handles of the instrument of  FIGS. 1-2 , highlighting the ratchet assembly.  
         [0014]      FIG. 5  illustrates the ratchet assembly of  FIG. 4  in a locked position.  
         [0015]      FIG. 6  illustrates the ratchet assembly of  FIG. 4  in an unlocked position.  
         [0016]      FIG. 7  illustrates the ratchet assembly of  FIG. 4  in another unlocked position.  
         [0017]      FIG. 8  illustrates in detail the unlocked position of  FIG. 7 .  
         [0018]      FIG. 9  illustrates an exposed section of the ratchet assembly incorporated into a wishbone handle design. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0019]      FIG. 1  illustrates a perspective view of surgical instrument  10 . Here, instrument  10  has handle assembly  14 , ratchet assembly  18 , and jaw assembly  22 . Body assembly  26  connects an operative device, such as a jaw assembly  22 , to handle assembly  14  through transmitting rod  30 . The jaw assembly  22  connects to the distal end of the transmitting rod  30  and the handle assembly  14  connects to the proximal end. Handle assembly  14 , or other such hand mechanism, has first handle  42  and second handle  46 . Jaw assembly  22  has first jaw portion  92  and second jaw portion  96 , which are pivotally connected at jaw pivot  180 . As will be explained in further detail, opening of first handle  42  in the direction of arrow A causes first jaw portion  92  to open relative to second jaw portion  96  in the direction of arrow C. Conversely, closing of first handle  42  in the direction of arrow B causes first jaw portion  92  to close in the direction of arrow D relative to second jaw portion  96 .  
         [0020]     Inventive instrument  10  has locking mechanism, such as a ratchet assembly  18 , that locks first handle  42  relative to second handle  46  to thereby lock first jaw portion  92  relative to second jaw portion  96  at any position between a completely closed position as shown in  FIG. 3  to a completely open position. When first handle  42  is moved in either the direction of arrow A or arrow B, ratchet assembly  18  is disengaged. When movement is stopped, ratchet assembly  18  is automatically engaged. Hence, instrument  10  automatically operates to lock jaw assembly  22  without additional effort to engage or disengage ratchet assembly  18 .  
         [0021]     As shown in  FIG. 3 , jaw assembly  22  has first jaw portion  92  and second jaw portion  96 . First jaw portion  92  has first teeth section  100  located at the distal end of transmitting rod  30  and back portion  124  located more proximal to transmitting rod  30 . Between first teeth section  100  and back portion  124  is provided first gap portion  112 , a length of first jaw portion  92  that has no teeth and is provided with a gap. Similarly, second jaw portion  96  has second teeth section  104 , second gap portion  116 , and back portion  124 . When first jaw portion  92  is closed relative to second jaw portion  96 , an eyelet  108  is formed by first gap portion  112  and second gap portion  116  between teeth sections  100 ,  104  and back portion  124 . Eyelet  108  is sized larger than suture  120  so that suture  120  may slide through eyelet  108 , thereby permitting movement through eyelet  108  of suture  120  along the Y axis but preventing movement of suture  120  along the X axis, as shown.  
         [0022]     The operation of instrument  10  will now be explained in detail with reference to  FIGS. 2 and 4 - 8 . Instrument  10  is shown in partial cross-section in  FIG. 2 . As shown, jaw assembly  22  is linked to handle assembly  14  by transmitting rod  30  housed within a shaft, such as transmitting rod housing  32 . Transmitting rod  30  is linked to first jaw portion  92  at jaw link  184 . Handle assembly  14  has first handle  42  and second handle  46 , which is formed as part of body assembly  26 . At body assembly  26 , first handle  42  is pivotally connected to second handle  46  through handle pivot  160 . Accordingly, first handle  42  may pivot relative to the second handle  46  in the direction of either arrow A or arrow B. Transmitting rod  30  is linked to first handle  42  at handle link  182 . Therefore, movement of first handle  42  in the direction of arrow A causes transmitting rod  30  to move in the direction of arrow G. First jaw portion  92  is pulled in the same direction and pivots first jaw portion  92  relative to second jaw portion  96  on jaw pivot  180 . First jaw portion  92  moves in the direction of arrow C relative to second jaw portion  96 . Movement of first handle  42  in the direction of arrow B causes transmitting rod  30  to move in the direction of arrow H, thereby pivoting first jaw portion  92  to close- in the direction of arrow D. It should be noted that first handle  42  is provided with well  176  that engages stop  172  on body assembly  26 . In this way, first handle  42  is prevented from closing or opening jaw assembly  22  beyond predetermined points to safeguard jaw assembly  22 .  
         [0023]     Ratchet assembly  18  is provided on instrument  10  to lock jaw assembly  22  in a particular position. Ratchet assembly  18  has ratchet arm  62 , which is pivotally linked to first handle  42  at pivot pin  72  through pivot hole  76  on ratchet arm  62 . Accordingly, ratchet arm  62  pivots in the direction of arrow E or in the direction of arrow F, as shown in  FIG. 2 . Ratchet arm  62  is provided with spring  68 , a leaf spring, that engages first handle top portion  50 . Spring  68  is biased in the direction of arrow E so that ratchet arm  62  is engaged to an engagement plate  66  of second handle  46 . The engagement plate  66  is mounted to second handle  46  by pins  140 . When first handle  42  and second handle  46  are not moved relative to each other, spring  68  biases ratchet arm  62  into engagement with the engagement plate  66  so that first handle  42  is locked in position relative to second handle  46  and accordingly first jaw portion  92  is locked in position relative to second jaw portion  96 .  
         [0024]     As shown in  FIG. 4 , first handle  42  comprises first handle top portion  50  and first handle bottom portion  54 . First handle top portion  50  has pivot base  52 , which is received on handle pivot  160  of body assembly  26  through pivot hole  51 . First handle top portion  50  further has first upper portion leg  144  and second upper portion leg  148 . Each leg  144 ,  148  is provided with first upper holes  128  and second upper holes  132 . First upper portion leg  144  and second upper portion leg  148  are sized to receive ratchet arm  62  so that spring  68  is nestled between first upper portion leg  144  and second upper portion leg  148  against first handle top portion  50 . Also, ratchet arm  62  has pivot hole  76  and release hole  84 , which are arranged to align with first upper hole  128  and second upper hole  132 , respectively, when ratchet arm  62  is received between first upper portion leg  144  and second upper portion leg  148 .  
         [0025]     First handle bottom portion  54  has finger loop  34  sized to receive a finger as well as support shoulder  40 , which is shaped to receive another finger. First handle bottom portion  54  further has first lower portion leg  152  and second lower portion leg  156 . Each leg  152 ,  156  has first lower holes  136  and second lower holes  142 . First lower portion leg  152  and second lower portion leg  156  are sized to receive first upper portion leg  144  and second upper portion leg  148 . Accordingly, when first handle  42  is fully assembled, as shown in  FIG. 2 , first upper holes  128  align with pivot hole  76  and first lower holes  136  while second upper holes  132  align with release hole  84  and second lower holes  142 .  
         [0026]     When the holes are aligned, pivot pin  72  is placed through first lower holes  136 , first upper holes  128 , and pivot hole  76 . Release pin  80  is placed through second lower holes  142 , second upper holes  132 , and release hole  84 . Pivot pin  72  and release pin  80 , or similar feature, are capped at each end to retain their position within these holes.  
         [0027]     The size of the holes relative to each other and to pins  72  and  80  assist ratchet assembly  18  in its engagement and disengagement with the engagement plate  66 . Referring again to  FIG. 4 , first lower holes  136  and second lower holes  142  have about the same diameter as pivot pin  72  and release pin  80 , say 0.062 inches. First upper holes  128  and second upper holes  132  of first handle top portion  50  have different diameters. For example, first upper holes  128  may have a diameter of 0.0620 inches while second upper holes  132  may have a larger diameter, say 0.072 inches. Also, ratchet arm  62  has holes of differing sizes. Pivot hole  76  has a diameter of, say 0.0620 inches. Release hole  84  has a diameter, say 0.072 inches. Accordingly, because of the size of pivot pin  72  and release pin  80 , ratchet arm  62  may not only pivot on pivot  72  but has some freedom of movement to move about pivot pin  72  and release pin  80 , particularly release pin  80 , which is in this case about 0.01 inches smaller than release hole  84 .  
         [0028]     The functioning of ratchet assembly  18  with respect to these holes will now be explained with reference to  FIG. 5-8 .  FIG. 5  illustrates a close-up view of handle assembly  14  in cross-section. As shown, ratchet arm  62  is mounted to pivot pin  72  by pivot hole  76  and pivots about pivot pin  72  in the direction of arrow E or F. In addition, release pin  80  is shown mounted through release hole  84  of ratchet arm  62 . As shown, there is space between release pin  80  and release hole  84  so that release pin  80  does not touch the sides of release hole  84  in the position shown in  FIG. 5 , which is the position where no force is applied to first handle  42 . In this position, the ratchet arm  62  is decoupled from movement with the first handle bottom portion  54 . Ratchet arm  62  has spring  68 , which engages first handle top portion  50 . Spring  68  is biased so that ratchet arm  62  engages the engagement plate  66  as shown. In addition, there is a ratchet opening  58  provided that permits movement of ratchet arm  62  in the direction of arrow F away from engagement with the engagement plate  66 . As shown in  FIG. 6 , when pressure is applied to first handle bottom portion  54 , release pin  80  contacts release hole  84  in the direction of arrow A overcoming the bias of spring  68 . Thus, first handle bottom portion  54  acts as a release mechanism for the ratchet arm  62 . In this position, the ratchet arm  62  is coupled with the first handle bottom portion  54  thereby linking movement of the first handle bottom portion  54  with the ratchet arm  62 . As a consequence, ratchet arm  62  pivots about pivot pin  72  in the direction of arrow F into ratchet opening  58 . Hence, ratchet arm  62  is disengaged from the engagement plate  66 . As a consequence, further movement of first handle bottom portion  54  in the direction of arrow A is permitted and causes ratchet arm  62  to move generally in the same direction. First jaw portion  92  may then open relative to second jaw portion  96  in the direction of arrow C. When force is no longer applied to first handle bottom portion  54 , then handle assembly  14  releases pressure on spring  68 , allowing spring  68  to bias ratchet arm  62  into engagement with the engagement plate  66  as shown in  FIG. 5 .  
         [0029]     On the other hand, as shown in  FIG. 7 , if a surgeon wishes to close jaw assembly  22 , first handle bottom portion  54  is moved back in the direction of arrow B. Movement in this direction compresses spring  68 . This pressure on spring  68  is released as ratchet arm  62  is moved back generally in the direction of arrow B. Ratchet teeth  64  are angled relative to the engagement plate teeth  68  so as to permit ratchet arm  62  to slide across engagement plate teeth  68  in the direction of arrow B as shown in  FIG. 8 . It should be noted that here, release pin  80  does not contact the side of release hole  84  because spring  68  will cause ratchet arm  62  to slide across the engagement plate teeth  68  and engagement plate detents  67  without engagement until pressure on first handle bottom portion  54  is stopped. Once stopped, ratchet arm  62  engages the engagement plate  66  by engaging ratchet teeth  64  to the engagement plate teeth  68  and engagement plate detents.  
         [0030]     In addition to the heretofore described handles  14  having ring-type profiles, instrument  10  may utilize a set of wishbone type handles  16  as shown in  FIG. 9 . The ratchet assembly  18  interfaces with the wishbone handles  16  in the same manner as the ring handles  14 . Movement of a first wishbone handle bottom portion  56  relative to a second wishbone handle  48  actuates the ratchet assembly  18 .  
         [0031]     Although a preferred embodiment of this invention has been disclosed, a worker of ordinary skill in the art might recognize that certain modifications are possible that would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope of protection given for this invention.