Patent ID: 6123058
Filing Date: 2000-09-26
Classification: F02D,F02M,F02P

Abstract:
An injector drive circuit for driving, in response to an injection command signal having a time width corresponding to fuel injection time, an injector which includes a valve for operating an injection port and a solenoid coil for driving the valve and is constructed so as to open the valve to inject fuel into a fuel injection space of an internal combustion engine when the solenoid coil is fed with a predetermined drive current, comprising:a power circuit for outputting a first DC voltage having a level equal to or above a level of a drive voltage required to be applied to said solenoid coil when said valve is rendered open while using a magneto driven by said internal combustion engine as a power supply therefor;a voltage accumulation means for accumulating said first DC voltage therein;a capacitor charged by means of the voltage accumulated in said voltage accumulation means during a period of time for which said injection command signal is kept from being generated;a drive current feed circuit for applying a voltage across said capacitor to said solenoid coil to feed the drive current to said solenoid coil when it is fed with said injection command signal; anda holding current feed power supply section for feeding said solenoid coil with a holding current required to keep said valve open after the drive current fed from said capacitor to said solenoid coil passes a peak value.