Abstract: A surgical instrument includes an end effector, a shaft assembly, and a torque wrench integrally connected with the shaft assembly. The shaft assembly has an acoustic waveguide extending therethrough and the end effector projects distally from the shaft assembly. The acoustic waveguide has a proximal end portion configured to rotatably couple with an ultrasonic transducer assembly. The torque wrench is configured to transmit torque applied to the acoustic waveguide up to a predetermined torque. A portion of the torque wrench is configured to deflect upon receipt of torque greater than the predetermined torque. Accordingly, the portion of the torque wrench slips relative to the acoustic waveguide for limiting coupling of the acoustic waveguide to the ultrasonic transducer assembly to the predetermined torque.

Abstract: An insertion part of an endoscope and an insertion part of a treatment tool, which are inserted in an outer tube, can be synchronously moved in the axial direction, and, even when the insertion part of the treatment tool is slightly moved in the axial direction, an excellent endoscopic image without shake is obtained. When a treatment tool of an endoscopic surgery device moves by a displacement amount over an allowance amount, an endoscope moves in interlock with the movement of the treatment tool. Moreover, the treatment tool 50 moves in the axial direction with the allowance amount t with respect to the endoscope 10. Therefore, when the treatment tool is moved by a displacement amount of allowance amount or less, the endoscope does not move. By providing such allowance amount, slight movement of the treatment tool is not transmitted to the endoscope.