ULTRASONIC MOTOR

PURPOSE:To obtain an ultrasonic motor which can remarkably improve its output torque while the motor has the same hardware constitution as the conventional motor has. CONSTITUTION:A rotor is pressed against a vibrating body with such a pressing force that an amplitude belonging to the area (second resonance mode area) after a point of time when the resonance amplitude changes from a decrease to an increase when the rotor pressing force against the vibrating body is increased. In other words, the rotor is pressed against the vibrating body with such a pressing force that can generate an amplitude belonging to the area after the point of time when the resonance frequency abruptly changes.