| 摘要 |
PROBLEM TO BE SOLVED: To suppress excessive pressure rise in a pump chamber of a high pressure fuel pump. SOLUTION: A high pressure fuel pump 3 compresses fuel in a pump chamber 39 synchronously with the rotation of a crankshaft of an engine. A valve element 56 of a solenoid valve 5 is controlled to open/close so as to allow or impede communication between the pump chamber 39 and a low pressure fuel chamber 41. An axially piercing hollow part 59 is formed in the valve element 56 of the solenoid valve 5. A stopper 60 is fixed to the hollow part 59, and a ball 62 always energized into a closed position (downward in a figure) by a compression coil spring 61 is accommodated in the hollow part 59. The hollow part 59 is communicated with low pressure side passages 53, 42 through a communicating path 63. Pressure of fuel in the pump chamber 39 acts upon the ball 62 accommodated in the hollow part 59, through a passage of a plate. A valve member formed of the compression coil spring 61 and the ball 62 opens when fuel pressure of the pump chamber 39 exceeds the specified value so as to communicate the pump chamber 39 with the low pressure side. |
