Fuel pump for high-pressure fuel injection system
A fuel pump for a high-pressure fuel injection system includes a high-pressure fuel pump 4 for supplying high-pressure fuel to injectors 8 for injecting high-pressure fuel into cylinders of an engine, a pressure control valve 10 for controlling the fuel pressure of the high-pressure fuel pump 4, a high-pressure fuel supply pipe 16 connecting the high-pressure fuel pump 4 and the injectors 8, a high-pressure fuel control pipe 17 connecting the injectors 8 and the pressure control valve 10, and a pump-control valve communication passage 18 formed to communicate the high-pressure fuel pump 4 with the pressure control valve 10 and bypass the injectors 8, the sectional area of the pump-control valve communication passage 18 being smaller than those of the high-pressure fuel supply pipe 16 and the high-pressure fuel control pipe 17. Owing to the provision of the pump-control valve communication passage 18, the high-pressure fuel pump of the fuel pump for a high-pressure fuel injection system can secure a pressure relief function without separate installation a relief valve.