PURPOSE: To perform pilot injection at a normal timing by bleeding pressure in a variable volume chamber of an actuator when a port is shut off, and thereby eliminating fuel injection when the fuel injection is unnecessary, and fuel injection unrelated to jetting.
CONSTITUTION: When fuel in a high pressure chamber 32 is pressurized by moving a plunger 4 in a direction of an arrow Y, a port 48 leading to the high pressure chamber 32 is communicated with a passage 53 connected to a variable volume chamber 52. A voltage is applied to an actuator 5, and the variable volume chamber 52 is pressurized by extending a piezoelectric element 51. The pressure passes through the passage 53, the port 48, a discharge port 43 and a distribution passage 24 to open a delivery valve 25, so that fuel is injected from an injection nozzle 10. On the other hand, when the port is shut off, residual high pressure fuel in the variable volume chamber 52 is flowed once to a delivery chamber 27. The pressure in the variable volume chamber 52 does not reach a thresh hold level, so that unnecessary fuel injection is eliminated which otherwise may effect and internal combustion engine out of timing.
KATO NOBUO
TAKEMOTO HIDETSUGU
