| 摘要 |
PURPOSE:To effectively prevent a hysteresis from generating upon elongation or shrinkage of a ceramic actuator by controlling a charging current to a reverse piezoelectric effect ceramic actuator or a discharge current from from the actuator constantly. CONSTITUTION:When the level of a control signal from control signal generating means 30 is higher than a charging voltage Vc of a capacitor 20, charging current control means 110 so controls that a charging current to a ceramic actuator 10 from a DC power source B becomes constant in response to the difference of a charge detection voltage and a constant voltage due to the inhibition of the control operation of discharge current control means 120. On the other hand, when the level to the control signal is lower than a charging voltage Vc, the means 120 so controls that a discharge current from the actuator 10 becomes constant in response to the difference of the discharge detection voltage and the constant voltage due to the inhibition of the control operation of the means 110. |
