PIEZOELECTRIC ACTUATOR CONTROLLER AND FUEL INJECTION CONTROLLER FOR DIESEL ENGINE WITH PIEZOELECTRIC ACTUATOR CONTROLLER

摘要

PURPOSE:To prevent the deterioration of the polarization of a piezoelectric actuator at low cost by applying high voltage to the piezoelectric actuator and conducting re-polarization operation when an expansion control means for the piezoelectric actuator is not operated. CONSTITUTION:When an ignition switch 19 is turned ON, a piezoelectric actuator mounted to a fuel injection pump is worked by an injection-rate controller drive circuit 15, and the operation of the fuel injection pump takes the type of pilot injection, etc. for reducing noises and vibrations. When the ignition switch 19 is turned OFF, a piezoelectric DC/DC converter 91 applies high voltage to the piezoelectric actuator for a fixed time by a timer 98, thus resulting in the re-polarization of the piezoelectric actuator.