Surgical instrument having a power control circuit

Abstract

Various embodiments are directed to a powered surgical instrument for cutting and fastening tissue. The instrument may comprise an end effector comprising a first jaw member and a second jaw member. The second jaw member may be coupled to move relative to the first jaw member from an open position, where the jaw members are apart from one another, to a closed position. The end effector may also comprise a firing bar positioned to fire by translating within the end effector when the first and second jaw members are in the closed position. Additionally, the surgical instrument may comprise a drive device, a clamping trigger and a control circuit. The drive device may be mechanically coupled to the firing bar. The clamping trigger may be mechanically coupled to the end effector such that actuation of the clamping trigger causes the second jaw member to pivot towards the first jaw member. The control circuit may comprise a firing switch, a clamp switch, a latching device and an end-of-stroke sensor. The firing switch may be configured to be in electrical communication with a power supply for powering the drive device and in electrical communication with the drive device. The clamp switch may be in mechanical communication with the clamping trigger. The latching device may be in electrical communication with the clamp switch, the power supply and the drive device. The end-of-stroke switch may be in electrical communication with the latching device. Additionally, the firing switch may be electrically connected to, upon actuation, connect the power supply to the drive device via a first connection comprising the latching device and the firing switch. Further, the end-of-stroke switch may be electrically connected to, upon sensing an end of a stroke of the firing bar, cause a change in a state of the latching device to break the first connection between the power supply and the drive device.