Patent ID: 6522049
Filing Date: 2003-02-18
Classification: F02D,H02N

Abstract:
An apparatus for detecting a short circuit from a piezoelectric element (10, 20, 30, 40, 50, or 60) to a battery voltage when driving the piezoelectric element (10, 20, 30, 40, 50, or 60), the apparatus characterized by:an element selection switch for selecting the piezoelectric element for operation; an operation selection switch for selecting a charging or discharging circuit to be connected to the piezoelectric element (10, 20, 30, 40, 50, or 60); and a control unit (D) that activates the element selection switch for a predetermined time interval before activating the operation selection switch, the control unit (D) further generating an error signal if a current measurement is greater than a predetermined maximum during the predetermined time interval.