| 摘要 |
PURPOSE:To compensate for the change in speed due to the change in temperature and the fluctuation of the load by variably controlling the voltage and the frequency which are applied to a piezoelectric body, a driving source of an ultrasonic motor. CONSTITUTION:An oscillation condition detecting device 6 is installed on an oscillating body 3. And, a voltage control device 8 which controls the voltage to be applied to a piezoelectric body so that the detected voltage may be kept at the set value and a frequency tracking device 7 which controls the frequency of the voltage to be applied to the piezoelectric body so that the phase difference between the detected voltage and the applied voltage may be kept at the set value are installed on the entire device. |
