| 摘要 |
PURPOSE:To prevent a piezoelectric actuator from being displacement-drifted, by returning operation voltage to desired voltage, after the operation voltage exceeding the desired voltage is applied to the piezoelectric actuator for a given time and the directions of inductive polarization in a piezoelectric element are aligned. CONSTITUTION:The input of latch signal is provided, and at the same time, from a timer 16, the output of the pulse of a specified pulse width is generated, By the pulse, an analog switch 19 is turned ON, and an analog switch 17 is turned OFF, and to an operation amplifier 20, the output voltage of a D/A converter 12 and an operation amplifier 15 is applied. Then, on a piezoelectric actuator, the output of operation voltage exceeding desired voltage is generated. When the pulse output of the timer 16 is completed, then the switch state of the analog switches 17, 19 is reversed and to the operation amplifier 20, the output voltage of the D/A converter 12 and earth potential are applied. As a result, o the piezoelectric actuator, the output of the operation voltage of the desired voltage is generated. |
