Endoscopic bipolar electrocautery instruments

Abstract

An endoscopic bipolar electrocautery instrument includes a proximal actuator coupled by a tube and push rod to a pair of distal graspers. The tube is covered with an insulating shrink wrap from its distal end up to an uncovered proximal portion. A stationary jaw with an integral clevis is mounted inside the distal end of the tube and electrically contacts the inner surface thereof. The clevis holds a pair of ceramic insulators between which a movable jaw is mounted on an insulated bushing with an axle pin. The movable jaw is electrically and mechanically coupled to the push rod which is covered with an insulating shrink wrap from a point just proximal of its connection with the movable jaw to a point near its proximal end. The uninsulated proximal end of the tube is mounted in a conductive bushing which rotates within a nonconductive handle. The proximal end of the push rod extends beyond the conductive bushing and a rubber insulator is fitted between the bushing and the push rod. A nonconductive actuating lever is hingedly attached to the handle and the push rod is rotatingly coupled thereto. A pair of Y-shaped electrical wiper contacts are insert molded in a nonconductive member mounted in the handle and respectively contact the bushing and uninsulated portion of the push rod on either side of the rubber insulator. A bipolar cable insert molded in the nonconductive member is coupled to these contacts and to a source of current.