| 摘要 |
PURPOSE:To drive an ultrasonic wave motor steadily and efficiently, by using a result from exact detection of a mechanical arm current flowing into a piezoelectric body. CONSTITUTION:A circuit made up of a rectifying device 12 and a capacitor 13 is connected at the output side of a driving circuit. Also, a serial circuit as an oscillating element for an ultrasonic wave motor, made up of a piezoelectric element 14 and a resistor device 15, is connected at the output side of the driving circuit, and the DC current is fed back so that the output voltage from a driving circuit is kept almost constant. Then, a current flowing into the piezoelectric element 14 is detected and controlled by using a voltage across the resistor device 15. Consequently, a vibration element is always driven in a stable operation range. |
