Patent ID: 8604667

Claim:
An ultrasonic motor comprising: a disc-shaped or an annular piezoelectric element; a plurality of divided electrodes mounted on one surface of the piezoelectric element, the divided electrodes being equidistantly arranged in the circumferential and radial directions and having equal areas; an inner peripheral electrode arranged on an inner peripheral side of the divided electrodes; an outer peripheral electrode arranged on an outer peripheral side of the divided electrodes; a plurality of inner peripheral short-circuiting electrodes mounted on every other divided electrode out of the divided electrodes and on the inner peripheral electrode so as to make said every other divided electrode short-circuited with the inner peripheral electrode in the radial direction of the piezoelectric element; a plurality of outer peripheral short-circuiting electrodes mounted on the divided electrodes which are not short-circuited with the inner peripheral electrodes out of the divided electrodes and on the outer peripheral electrode so as to make the divided electrodes which are not short-circuited with the inner peripheral electrode short-circuited with the outer peripheral electrode in the radial direction of the piezoelectric element; an oscillating body connected to the piezoelectric element; a moving body in contact with the oscillating body; and a pressurizing member which brings the oscillating body and the moving body into pressure contact with each other.