Patent ID: 6832601
Filing Date: 2004-12-21
Classification: F02D

Abstract:
A control device for controlling a fuel injection valve comprising:an auxiliary power supply for stepping up voltage from a main power supply mounted on a vehicle; a first switching element for conducting voltage from said auxiliary power supply to an electromagnetic solenoid for driving a fuel injection valve; a second switching element for conducting voltage from said main power supply to said electromagnetic solenoid; a third switching element that possesses a withstanding voltage limiting characteristic larger than a maximum output voltage from said auxiliary power supply, and interrupts a supply current to said electromagnetic solenoid at a high speed; current detection means for detecting conduction current to said electromagnetic solenoid; valve-opening signal generation means for inputting an operation information of an internal combustion engine and outputting a valve-opening signal and a valve-opening drive signal corresponding to a valve-opening time and a valve-opening time period of said fuel injection valve; and conduction control means for controlling a power feed to said electromagnetic solenoid in response to a signal of said valve-opening signal generation means; wherein said conduction control means performs a rapid power feed from said auxiliary power supply to said electromagnetic solenoid by means of said first switching element in response to the valve-opening drive signal from said valve-opening signal generation means; said conduction control means performs a continuous power feed from said main power supply by means of said second switching element; said conduction control means performs a hold power feed under ON/OFF control of said second switching element by feedback control based on a current value detected by said current detection means during continuance of said valve-opening signal after said valve-opening drive signal has ended; said conduction control means interrupts a power feed to said electromagnetic solenoid at a high speed by means of said third switching element immediately after said valve-opening signal has ended; and minimum value of an output voltage from said auxiliary power supply is set to be larger than a maximum value of voltage of said main power supply, and a step-up operation of said auxiliary power supply is stopped during said rapid power feed.