DRIVING CIRCUIT FOR COMPOSITE OSCILLATOR TYPE ULTRASONIC MOTOR

摘要

PURPOSE: To provide a driving circuit wherein possibility of thermal destruction is eliminated by input power wasted under no-load condition to suppress generation of heat in an ultrasonic motor. ;CONSTITUTION: In a circuit for driving an ultrasonic motor comprising a stator having torsional oscillators 2, 3 and a longitudinal oscillator and a rotor, the circuit is constituted by parallelly connecting a high frequency oscillating circuit 15 and a DC power supply 14 to the torsional oscillators 2, 3 through a transformer 13 and by building a constant current supply means 16 for making constant a current, applied to the torsional oscillators 2, 3, between the transformer 13 and the DC power supply 14. Accordingly, by generating a fixed current by the constant current supply means at no-load time, continuously inputting of excessive power to the ultrasonic motor is eliminated.;COPYRIGHT: (C)1993,JPO&Japio