Alignment features for ultrasonic surgical instrument

Abstract

An ultrasonic instrument comprises a body, a shaft assembly, an ultrasonic blade, and a pivoting member. The shaft assembly extends distally from the body. The ultrasonic blade is positioned distal to the shaft assembly. The pivoting member is pivotable with respect to the blade from an open position to a closed position to thereby clamp tissue between the pivoting member and the blade. One or both of the shaft assembly or the pivoting member comprise a guide feature. The guide feature is configured to provide lateral alignment of the distal portion of the pivoting member with the blade as the pivoting member is pivoted to the closed position.

1 - 20 . (canceled) 
     
     
         21 . An ultrasonic instrument comprising:
 (a) a shaft assembly;   (b) an ultrasonic blade positioned distal to the shaft assembly;   (c) a clamp arm assembly comprising:
 (i) a clamp arm, wherein the clamp arm is pivotable with respect to the ultrasonic blade from an open position to a closed position to thereby clamp tissue between the clamp arm and the ultrasonic blade, 
 (ii) a first member extending proximally from the clamp arm, and 
 (iii) a second member extending proximally from the clamp arm, wherein the first member and the second member are spaced away from each other such that a portion of the shaft assembly extends between the first member and the second member; and 
   (d) a guide feature configured to laterally align the clamp arm relative to the ultrasonic blade as the clamp arm is pivoted toward the ultrasonic blade, wherein the guide feature comprises:
 (i) a first resilient guide member interposed between the first member of the clamp arm assembly and the shaft assembly, and 
 (ii) a second resilient guide member interposed between the second member of the clamp arm assembly and the shaft assembly, wherein the first resilient guide member and the second resilient guide member are configured to bear against the shaft assembly and respective portions of the first member and the second member to guide the clamp arm into alignment with the ultrasonic blade. 
   
     
     
         22 . The ultrasonic instrument of  claim 21 , wherein the first resilient guide member comprises a first spring having a first stiffness. 
     
     
         23 . The ultrasonic instrument of  claim 22 , wherein the second resilient guide member comprises a second spring having a second stiffness. 
     
     
         24 . The ultrasonic instrument of  claim 23 , wherein the first stiffness of the first resilient guide member is different than the second stiffness of the second resilient guide member. 
     
     
         25 . The ultrasonic instrument of  claim 23 , wherein the first member of the clamp arm assembly defines a first pocket, wherein the first resilient guide member is at least partially housed within the first pocket. 
     
     
         26 . The ultrasonic instrument of  claim 25 , wherein the second member of the clamp arm assembly defines a second pocket, wherein the second resilient guide member is at least partially housed within the second pocket. 
     
     
         27 . The ultrasonic instrument of  claim 23 , wherein the first spring comprises a first leaf spring, wherein the second spring comprises a second leaf spring. 
     
     
         28 . The ultrasonic instrument of  claim 23 , wherein the first spring comprises a first wave spring, wherein the second spring comprises a second wave spring. 
     
     
         29 . The ultrasonic instrument of  21 , wherein the clamp arm assembly comprises a proximal thumb ring. 
     
     
         30 . The ultrasonic instrument of  claim 29 , wherein the clamp arm assembly comprises an arm extending between the proximal thumb ring and the first member. 
     
     
         31 . The ultrasonic instrument of  claim 21 , further comprising a body comprises a proximal finger ring. 
     
     
         32 . The ultrasonic instrument of  claim 21 , wherein the clamp arm comprises a clamp pad. 
     
     
         33 . The ultrasonic instrument of  claim 21 , further comprising an activation button. 
     
     
         34 . The ultrasonic instrument of  claim 32 , further comprising a second activation button. 
     
     
         35 . The ultrasonic instrument of  claim 21 , further comprising a pin extending through the clamp arm assembly and the shaft assembly. 
     
     
         36 . ultrasonic instrument comprising:
 (a) a shaft assembly;   (b) an ultrasonic blade positioned distal to the shaft assembly;   (c) a clamp arm assembly comprising:
 (i) a clamp arm, wherein the clamp arm is pivotable with respect to the ultrasonic blade from an open position to a closed position to thereby clamp tissue between the clamp arm and the ultrasonic blade, 
 (ii) a first member extending proximally from the clamp arm, and 
 (iii) a second member extending proximally from the clamp arm, wherein the first member and the second member are disposed on opposite sides of the shaft assembly; and 
   (d) a guide feature configured to laterally align the clamp arm relative to the ultrasonic blade as the clamp arm is pivoted toward the ultrasonic blade, wherein the guide feature comprises:
 (i) a first resilient guide member interposed between an interior surface of the first member of the clamp arm assembly and the shaft assembly, and 
 (ii) a second resilient guide member interposed between an interior surface of the second member of the clamp arm assembly and the shaft assembly, wherein the first resilient guide member and the second resilient guide member are configured to bear against the shaft assembly to guide the clamp arm into alignment with the ultrasonic blade. 
   
     
     
         37 . The ultrasonic instrument of  claim 36 , wherein the interior surface of the first member defines a pocket, wherein the first resilient guide member is housed within the pocket. 
     
     
         38 . The ultrasonic instrument of  claim 36 , wherein the first resilient guide member comprises a leaf spring. 
     
     
         39 . The ultrasonic instrument of  claim 36 , wherein the clamp arm assembly comprises a clamp pad. 
     
     
         40 . An ultrasonic instrument comprising:
 (a) a shaft assembly;   (b) an ultrasonic blade positioned distal to the shaft assembly;   (c) a clamp arm assembly comprising:
 (i) a clamp arm, wherein the clamp arm is pivotable with respect to the ultrasonic blade from an open position to a closed position to thereby clamp tissue between the clamp arm and the ultrasonic blade, 
 (ii) a first member extending proximally from the clamp arm, and 
 (iii) a second member extending proximally from the clamp arm, wherein the first member and the second member are spaced away from each other such that a portion of the shaft assembly extends between the first member and the second member; and 
   (d) a resilient guide assembly configured to laterally align the clamp arm relative to the ultrasonic blade as the clamp arm is pivoted toward the ultrasonic blade, wherein the resilient guide assembly comprises:
 (i) a first leaf spring contacting the first member of the clamp arm assembly and the shaft assembly, and 
 (ii) a second leaf spring contacting the second member of the clamp arm assembly and the shaft assembly, wherein the first leaf spring and the second leaf spring are configured to bear against the shaft assembly and respective portions of the first member and the second member to guide the clamp arm into alignment with the ultrasonic blade.