Pilot injection control device for diesel engine

Abstract

Abstract PURPOSE:To properly perform pilot injection completely independently of main injection by decreasing reference voltage in accordance with an increase of engine speed, in case of performing the pilot injection when generated voltage of a piezoelectric element exceeds the reference voltage. CONSTITUTION:In a distributor-type fuel injection pump, fuel in a pressure fuel chamber 3 is pressurized following the movement of a plunger 2 and injected from a fuel injection valve 9 via a fuel delivery passage 8. While in a pilot injection control device 10, a piezoelectric element 13 generates voltage in accordance with a pressure of fuel in a variable volume chamber 15 communicating with inside the pressure fuel chamber 3. When the generated voltage exceeds the reference voltage, a driving circuit 22 extends the piezoelectric element 13 decreasing the volume in the variable volume chamber 15, and pilot injection is performed. In this device, the driving circuit 22 is controlled by an electronic control unit 30 being based on a detection signal from an engine speed sensor 23. And the reference voltage is decreased in accordance with an increase of an engine speed.

Inventors

• 👤 Hiromichi Yanagihara
• 👤 弘道 柳原
• 👤 Yoshimitsu Henda
• 👤 良光 辺田

Bibliographic Details