Abstract: A piezoelectric valve, having superior responsiveness during valve opening and capability to stabilize gas supply at an early stage, includes a gas pressure chamber receiving compressed gas and an exhaust path discharging the compressed gas from the gas pressure chamber; a valve disc placed in the gas pressure chamber to open and close the exhaust path; a piezoelectric element generating a driving force for operation of the valve disc, as a displacement; a displacement magnifying mechanism magnifying the displacement of the piezoelectric element and applying the magnified displacement to the valve disc; and driving means including a signal generator generating a signal including a first prepulse, a second prepulse, and a main pulse, applies a drive voltage to the piezoelectric element using the signal generated by the signal generator, as an input signal to a drive circuit, and drives and opens the valve disc by expanding the piezoelectric element.

Abstract: The piezoelectric actuator includes a piezoelectric element; a power supply applying a voltage to the piezoelectric element; a drive circuit that applies a voltage from the power supply to the piezoelectric element by a pulse charge signal and a discharge signal to charge, and discharges the charge charged in the piezoelectric element to drive the piezoelectric element; an abnormality detection circuit that detects an abnormality due to insulation failure of the piezoelectric element, and a control unit that determines whether or not the piezoelectric element is normal based on an abnormality detection signal. The abnormality detection circuit outputs the abnormality detection signal that detects a time corresponding to a period from when a current starts to flow to the piezoelectric element during charging to when a current stops to flow, and it is determined that the piezoelectric element is abnormal when the time is equal to or more than a set time.

Abstract: A piezoelectric valve, having superior responsiveness during valve opening and capability to stabilize gas supply at an early stage, includes a gas pressure chamber receiving compressed gas and an exhaust path discharging the compressed gas from the gas pressure chamber; a valve disc placed in the gas pressure chamber to open and close the exhaust path; a piezoelectric element generating a driving force for operation of the valve disc, as a displacement; a displacement magnifying mechanism magnifying the displacement of the piezoelectric element and applying the magnified displacement to the valve disc; and driving means including a signal generator generating a signal including a first prepulse, a second prepulse, and a main pulse, applies a drive voltage to the piezoelectric element using the signal generated by the signal generator, as an input signal to a drive circuit, and drives and opens the valve disc by expanding the piezoelectric element.