Method and device for driving a supersonic motor.

摘要

A method for driving a supersonic motor comprises the steps of: driving the supersonic motor by supplying a driving voltage of a fully higher frequency than a resonant point to the driving piezoelectric element, decreasing a driving frequency when a waveform distortion does not generate in an output signal of the oscillation detection piezoelectric element provided in the elastic body, and increasing the driving frequency when the waveform distortion generates in the output signal of the oscillation detection piezoelectric element.