Trocar Seal with Retraction Induced Hinge

Abstract

A trocar comprising an alignment channel and an instrument seal comprising a bending portion and a base portion. The bending and base portions of the instrument seal are spaced relative the alignment channel such that when a surgical instrument is retracted the bending portion inverts and the lip does not enter the alignment channel.

1 - 20 . (canceled) 
     
     
         21 . An instrument seal for use in a trocar with an alignment channel, the instrument seal comprising a mounting seal, a base portion extending medially and distally from the mounting seal, and a bending portion extending medially from the base portion, wherein the base portion has a thickness greater than a thickness of the bending portion. 
     
     
         22 . The instrument seal of  claim 21 , wherein the base portion and bending portion have respective wall thicknesses with a ratio between about 1.5:1 and about 4:1. 
     
     
         23 . The instrument seal of  claim 21 , wherein the bending portion has a generally frusto-conical geometry. 
     
     
         24 . The instrument seal of  claim 23 , wherein the base portion has a generally cylindrical geometry. 
     
     
         25 . The instrument seal of  claim 21 , wherein the bending portion further comprises a lip defining an opening. 
     
     
         26 . The instrument seal of  claim 21 , further comprising a hinge area adjacent the base and bending portions. 
     
     
         27 . The instrument seal of  claim 21 , wherein the mounting seal is annular. 
     
     
         28 . A instrument seal for use in a trocar having a cannula with a distal end, a housing with a proximal end, and an alignment channel aligned with the cannula and positioned distally relative to the housing proximal end, the alignment channel having a length and an inside diameter, the length being greater than the inside diameter, the instrument seal comprising: a lip defining an opening adapted to be aligned with the alignment channel and positioned distally relative to the alignment channel, a bending portion extending laterally and proximally from the lip, a base portion, a hinge area adjacent the base and bending portions, and a mounting seal positioned laterally from the base portion, wherein the base and bending portions have respective wall thicknesses and the base portion is thicker than the bending portion. 
     
     
         29 . The instrument seal of  claim 28 , wherein the thickness ratio of the base portion and bending portion is between about 2:1 and about 3:1. 
     
     
         31 . The instrument seal of  claim 28 , wherein the base portion is adapted to abut the alignment channel.