Actuation mechanism for use with an ultrasonic surgical instrument

Abstract

An ultrasonic surgical instrument is disclosed including an end effector, a shaft assembly extending proximally from the end effector, and a housing extending proximally from the shaft assembly. The end effector includes a clamp arm assembly pivotable between an open position and a closed position. The clamp arm assembly includes a clamp arm including a slot, a tissue pad secured to the clamp arm, and a tab. The tissue pad includes a flange positioned in the slot. The tissue pad extends proximally to a proximal end. The tab is positioned to engage the proximal end to stop proximal displacement of the tissue pad relative to the clamp arm. Relative movement between an outer tube and an inner tube is configured to pivot the clamp arm assembly. Actuation of a trigger is configured to effect relative movement between the inner tube and the outer tube.

1 - 13 . (canceled) 
     
     
         14 . An ultrasonic surgical instrument, comprising:
 an end effector, comprising:
 a clamp arm assembly pivotable between an open position and a closed position, the clamp arm assembly comprising:
 a clamp arm comprising a slot; 
 a tissue pad secured to the clamp arm, the tissue pad comprising a flange positioned in the slot, wherein the tissue pad extends proximally to a proximal end; and 
 a tab positioned to engage the proximal end to stop proximal displacement of the tissue pad relative to the clamp arm; 
 
   a shaft assembly extending proximally from the end effector, the shaft assembly comprises:
 an outer tube; and 
 an inner tube, wherein relative movement between the outer tube and the inner tube is configured to pivot the clamp arm assembly between the open position and the closed position; and 
   a housing extending proximally from the shaft assembly, the housing comprising a trigger, wherein actuation of the trigger is configured to effect relative movement between the inner tube and the outer tube.   
     
     
         15 . The ultrasonic surgical instrument of  claim 14 , wherein the tab curves toward the proximal end of the tissue pad. 
     
     
         16 . The ultrasonic surgical instrument of  claim 14 , wherein the tab hooks at least partially around the proximal end of the tissue pad. 
     
     
         17 . The ultrasonic surgical instrument of  claim 14 , wherein the flange comprises:
 a first extension extending in a first lateral direction; and   a second extension extending in a second lateral direction.   
     
     
         18 . The ultrasonic surgical instrument of  claim 17 , wherein the slot is configured to receive the first extension and the second extension, and wherein the slot further comprises:
 a first ledge configured to abut the first extension; and   a second ledge configured to abut the second extension.   
     
     
         19 . The ultrasonic surgical instrument of  claim 14 , further comprising a nozzle coupled to the shaft assembly, wherein rotation of the nozzle is configured to rotate the shaft assembly. 
     
     
         20 . The ultrasonic surgical instrument of  claim 14 , wherein the tissue pad comprises a plurality of tissue-gripping teeth. 
     
     
         21 . The ultrasonic surgical instrument of  claim 14 , wherein the end effector further comprises an ultrasonic blade. 
     
     
         22 . The ultrasonic surgical instrument of  claim 21 , wherein the housing comprises a switch, and wherein a transducer is configured to apply ultrasonic vibrations to the ultrasonic blade based on actuation of the switch. 
     
     
         23 . An ultrasonic surgical instrument, comprising:
 an end effector comprising a clamp arm assembly rotatable between an open position and a closed position, the clamp arm assembly comprising:
 a clamp arm comprising a longitudinal recess; 
 a tissue pad secured to the clamp arm, the tissue pad comprising a longitudinal projection positioned in the longitudinal recess; and 
 a stop positioned proximal to the tissue pad, wherein the stop is structured and positioned to restrain proximal displacement of the longitudinal projection within the longitudinal recess. 
   
     
     
         24 . The ultrasonic surgical instrument of  claim 23 , wherein the stop curves toward a proximal end of the tissue pad. 
     
     
         25 . The ultrasonic surgical instrument of  claim 23 , wherein the stop extends at least partially around a proximal end of the tissue pad. 
     
     
         26 . The ultrasonic surgical instrument of  claim 23 , wherein the longitudinal projection comprises:
 a first extension extending in a first lateral direction; and   a second extension extending in a second lateral direction.   
     
     
         27 . The ultrasonic surgical instrument of  claim 26 , wherein the longitudinal recess is configured to receive the first extension and the second extension, and wherein the longitudinal recess further comprises:
 a first ledge configured to abut the first extension; and   a second ledge configured to abut the second extension.   
     
     
         28 . The ultrasonic surgical instrument of  claim 23 , wherein the tissue pad comprises a tissue-engaging surface comprising teeth. 
     
     
         29 . The ultrasonic surgical instrument of  claim 23 , wherein the end effector further comprises an ultrasonic blade. 
     
     
         30 . An ultrasonic end effector, comprising:
 a clamp arm assembly, comprising:
 a clamp arm comprising a longitudinal cavity, wherein the longitudinal cavity comprises a first lateral ledge and a second lateral ledge; and 
 a tissue pad comprising a proximal end and a longitudinal projection positioned in the longitudinal cavity, wherein the longitudinal projection comprises:
 a first lateral extension in abutting contact with the first lateral ledge; and 
 a second lateral extension in abutting contact with the second lateral ledge; and 
 
 a hook extending at least partially around the proximal end of the tissue pad, wherein the hook is structured and positioned to restrain proximal displacement of the longitudinal projection with the longitudinal cavity. 
   
     
     
         31 . The ultrasonic end effector of  claim 30 , wherein the first lateral extension and the second lateral extension form a portion of a T-shaped flange. 
     
     
         32 . The ultrasonic end effector of  claim 30 , wherein the tissue pad comprises tissue-gripping teeth. 
     
     
         33 . The ultrasonic end effector of  claim 30 , further comprising an ultrasonic blade, wherein the clamp arm assembly is movable relative to the ultrasonic blade between an unclamped position and a clamped position.