| 摘要 |
PROBLEM TO BE SOLVED: To easily set common rail pressure to the specified value by providing a passage for communicating a high pressure supply pump with a low pressure fuel passage, with a solenoid valve for force-feeding fuel from a pumping chamber to a common rail at the time of the valve being closed, and providing a pressure control valve between the common rail and the low pressure passage side. SOLUTION: During the operation of an engine, an ECU 12 discriminates and obtains a cylinder bottom dead center signal of a high pressure supply pump 7 from signals of a cylinder discriminating sensor and a cam angle sensor, and while control signals are sent from the ECU 12 to a spill control solenoid valve 9 at specified timing, the solenoid valve 9 is closed. While the solenoid valve 9 is closed, fuel pressurized in a pumping chamber of the pump 7 is fed into a common rail 4 via a check valve 6 and accumulated in the common rail 4. A solenoid type pressure control valve 16 is provided between the common rail 4 and a low pressure side fuel tank 11, and its electromagnetic coil is controlled according to the engine speed, load and fuel pressure of the engine 1 so as to maintain the common rail 4 to requested common rail pressure. |
