Patent ID: 8267300

Claim:
A surgical instrument having a handle portion that is operably coupled to an end effector that has an end effector portion that is selectively movable between an open position and a closed position, said surgical instrument comprising: a closure system operably interfacing with said end effector portion to selectively transmit opening and closing motions thereto; a closure trigger movably coupled to said handle portion and being selectively movable between first and second positions, said closure trigger interacting with said closure system such that movement of said closure trigger from said first position to said second position causes said closure system to apply said closing motions to said movable end effector portion and wherein movement of said closure trigger from said second position to said first position causes said closure system to apply said opening motion to said movable end effector portion; and a dampening system supported by said handle portion and interacting with said closure trigger to retard movement of said closure trigger from said second position to said first position, wherein said dampening system comprises: a passage formed in said handle portion and having a first end with a first opening therein and a second end with a second opening therein; a protrusion on said closure trigger extending into said passage through said opening in said first end, said protrusion sized relative to said passage to establish a substantially fluid tight sliding seal therewith as said closure trigger is moved from said first position to said second position; a movable valve member mounted within said passage and movable between a first valve position wherein said movable valve member blocks said second opening when said closure trigger moves from said second position to said first position and a second valve position exposing said second opening when said closure trigger is moved from said first position to said second position; and a third opening in said valve member that is smaller than said second opening.