Patent ID: 7654431

Claim:
A surgical instrument, comprising: an end effector including a proximal camming surface; an elongate shaft, wherein the elongate shaft defines a longitudinal axis, the elongate shaft further including a frame defining a lateral recess aligned with the longitudinal axis, wherein the lateral recess is proximate to a distal end of the elongate shaft; an articulation joint pivotally attaching the end effector to the distal end of the elongate shaft comprising a pivot axis distal to the proximal camming surface; a slide bar sized for lateral movement within the lateral recess and having a distal portion engaged to the proximal camming surface of the end effector to effect articulation of the end effector, wherein the slide bar is movable laterally relative to the longitudinal axis to effect articulation of the end effector; a lateral guide mechanism engaging the slide bar to the frame, wherein the lateral guide mechanism is operable to move the slide bar laterally relative to the longitudinal axis while maintaining parallel alignment of the slide bar to the longitudinal axis of the elongate shaft; and a handle portion proximally attached to the elongate shaft and operably configured to produce an articulation motion to laterally move the slide bar; wherein the proximal camming surface of the end effector comprises a gear segment and the distal portion of the slide bar comprises a gear rack; wherein the lateral guide mechanism comprises a channel formed laterally in the frame and a rib received in the channel, perpendicularly attached to the slide bar further comprising a flexible longitudinal portion connecting the rib to the gear rack, wherein manipulating the end effector causes backdriving of the gear segment that flexes the longitudinal portion, cocking the rib into binding engagement in the channel.