| 摘要 |
PURPOSE:To stabilize the stroke amount of a piezoelectric element by applying the first set voltage to the element, and applying the second set voltage through the second switching element after the prescribed time is elapsed after the operation. CONSTITUTION:The voltage of a DC power source 1 is raised by a DC/DC converter 12, stored in a capacitor 13, and applied to a piezoelectric element 2. A drive circuit for applying a voltage to the element 2 is formed of thyristors 14, 15, capacitors 16, 17 and a resonance coil 18, and a trigger signal S is input to drive the gates of the both thyristors 14, 15. Thus, the signal S is applied to the thyristor 14 to operate it after the prescribed time is elapsed after the operation of the thyristor 15, and the voltage application to the element 2 is controlled by setting the lapse of time to the desired value. The opening time of an injecting hole of a fuel injection valve can be, for example, controlled to the desired time by the drive control of the element 2. |
