To provide a high pressure plunger pump for fuel injection with such a structure as automatically venting air only by starting a pump without using a manual priming pump in discharging air in the piping from a fuel tank of the high pressure plunger pump for fuel injection to the pump.
The high pressure plunger pump has an air vent valve 30 with an intake port 35 communicating with a feed fuel pathway 8 between a feed pump 12 and an intake check valve 9, and an outlet port 21 of the air vent valve 30 communicates with a drain oil pathway 22. A poppet 31 energized by a valve spring 34 is disposed between the inlet port 35 and the outlet port 21 of the air vent valve 30. The poppet 31 has a first restriction pathway 32 between the intake port 35 and the outlet port 21 at a position where the poppet 31 is energized by the valve spring 34. At the start of operation, only the air in a fuel coil pathway 20 is discharged, and when discharge of the air is completed and the fuel oil is released, the poppet 31 automatically closes the outlet port 21 with the restriction resistance generated in the first restriction pathway 32.
EGAMI YUJI
SHIMOKUCHI TAMOTSU
