Patent attributes
An apparatus comprises a body, an ultrasonic transducer assembly, a shaft assembly, and a coupling assembly. The shaft assembly comprises an acoustic waveguide that is operable to selectively couple with the ultrasonic transducer assembly. The coupling assembly is operable to selectively transition between a first mode and a second mode. The acoustic waveguide is configured to rotate with the transducer assembly relative to the body when the coupling assembly is in the first mode. The acoustic waveguide is configured to rotate relative to the transducer assembly and relative to the body when the coupling assembly is in the second mode. The coupling assembly is further configured to prevent the transducer assembly from rotating relative to the body when the coupling assembly is in the second mode. The shaft assembly and the end effector are also together configured to transition between an operational mode and a cleaning mode.