Patent ID: 6378498
Filing Date: 2002-04-30
Classification: F02D

Abstract:
An accumulator type fuel injection system having an accumulator adapted to store therein a fuel pressurized by a fuel pump, and a fuel injection valve to which the fuel stored in said accumulator is supplied, the fuel stored in said accumulator being injected from said injection valve into a combustion chamber, said fuel injection system comprising:a first accumulator adapted to store therein a high-pressure fuel pressurized by said fuel pump, a plurality of fuel injection valves connected to said first accumulator via a plurality of fuel passages and having nozzles for injecting the fuel into said combustion chambers of said engine, a plurality of first control valves provided in said fuel passages and adapted to control the discharging of the high-pressure fuel in said first accumulator to a downstream side of said fuel passages, a second accumulator adapted to store therein a fuel the pressure of which is lower than that of the high-pressure fuel in said first accumulator and connected via branch passages to a plurality of portions of said fuel passages which are on a downstream side of said first control valves, a second control valve adapted to control the discharging of the low-pressure fuel in said second accumulator to an atmosphere-opened side, a failure detecting device that detects the occurrence of failure in said accumulator type fuel injection system, and a fuel control device adapted to control, during a regular operation of said engine, an operation for opening said first control valves in the midst of a period of time in which said fuel injection nozzles are opened and an operation for closing said first control valves simultaneously with the closure of said fuel injection nozzles, and set, when the occurrence of failure in said accumulator type fuel injection system is detected by said failure detecting device, a pressure of the fuel discharged from said fuel pump so that a fuel pressure in said fuel passages becomes not higher than a permissible pressure in said second accumulator.