Patent attributes
An apparatus for operating on tissue includes a body, a shaft, an ultrasonic blade, and an acoustic assembly. The shaft extends distally from the body. The blade is disposed at the distal end of the shaft. The acoustic assembly comprises an acoustic waveguide coupled with the blade, a piezoelectric transducer element, a fastener, and a coupling member. The transducer element defines an inner diameter surface and an outer diameter surface. The fastener is configured to secure the transducer element relative to the waveguide. The coupling member is configured to provide electrical continuity between the fastener and the inner diameter surface of the transducer element. The outer diameter surface of the transducer element includes an annular recess. Another coupling member is configured to provide electrical continuity between the annular recess of the piezoelectric transducer element and a power source while permitting the piezoelectric transducer element to rotate relative to the body.