Ultrasonic motor driving device and ultrasonic diagnosis apparatus

摘要

An ultrasonic motor drive device capable of prolong the service life of an ultrasonic motor by preventing the motor from being unstably operated when the motor is driven at a lower speed of at least two speeds. When the ultrasonic motor (3) is driven at a rather low speed in normal driving, the motor can be prevented from being unstably operated by its driving at a rather low speed by driving the motor at a rather high speed for each specified interval. Thus, the service life of the ultrasonic motor can be increased.