Trigger mechanism for surgical instruments

Abstract

A linear surgical stapler having clamping and firing triggers pivotally mounted to the frame of the instrument for pivotal rotation toward a hand grip is disclosed. The clamping trigger is positioned between the firing trigger and the hand grip. Each of the triggers are pivotally mounted to pivot pins spaced from each other within the body portion of the frame. Pivotal rotation of the first trigger is independent of pivotal rotation of the second trigger. When the clamping trigger is pivotally rotated toward the hand grip, the clamping and firing transmission assemblies move distally in tandem. Before the first trigger is pivoted, the firing transmission assembly blocks pivotal rotation of the second trigger. When the first trigger is pivoted, the initial distal movement of the firing transmission assembly enables the firing trigger to be in a position to pivotally rotate, and therefore cause the firing of staples. Additionally, a feature enabling the retention of the clamping trigger in intermediate and fully clamped positions is disclosed, where upon release of the retention feature, the clamping trigger can return to its original position by overriding the intermediate position. Finally, although the invention is described with particular reference to a linear stapler containing clamping and firing triggers, it has broader applicability to any surgical instrument which has first and second triggers pivotally actuated to transmit work to an end effector for performing first and second surgical functions during a desired surgical procedure.