US Patent 10117649 Surgical instrument assembly comprising a lockable articulation system

A surgical stapling apparatus is disclosed which comprises a shaft, an end effector, and an articulation joint, wherein the end effector is rotatable relative to the shaft about the articulation joint. The stapling apparatus further comprises a firing drive responsive to an input, an articulation drive, and a switch assembly configured to selectively couple the articulation drive to the input. The switch assembly is configured to lock the articulation drive in position when the articulation drive is not coupled to the input.