Patent ID: 7249591

Claim:
A fuel injection apparatus for an internal combustion engine, said apparatus comprising: a pressure intensifier for intensifying pressure of fuel supplied from a fuel injection pump; a fuel injection nozzle for injecting fuel having pressure intensified by the pressure intensifier into a cylinder of the internal combustion engine; a solenoid valve for performing control of intensifying pressure of the pressure intensifier or control of opening or closing the fuel injection nozzle; a first fuel discharge path through which fuel flowing out of the pressure intensifier or the fuel injection nozzle bypasses the solenoid valve to return the fuel into a low pressure side of a fuel system; a second fuel discharge path through which fuel flowing out of the solenoid valve bypasses the first fuel discharge path to return the fuel to a low pressure side of the fuel system; a hydraulically operated type 2-position switching valve having a first position that can introduce fuel discharged from the the fuel injection pump into the pressure intensifier or the fuel injection nozzle and a second position that can return fuel flowing out of the pressure intensifier or the fuel injection nozzle to a lower pressure side of the fuel system, wherein the solenoid valve has a solenoid valve chamber provided therein and has a sealing part for preventing fuel from leaking from this solenoid valve chamber to the outside and performs control of increasing or descrasing hydraulic pressure of fuel applied to the 2-position switching valve to switch a position of the 2-position switching valve.