초록 ▼

An electronic digital control system monitors and controls the operation of an engine fueling system. Signals activating injection for a plurality of cylinders are transmitted through a single line to a driving circuit for a single injector solenoid valve, while signals controlling accumulator fuel

An electronic digital control system monitors and controls the operation of an engine fueling system. Signals activating injection for a plurality of cylinders are transmitted through a single line to a driving circuit for a single injector solenoid valve, while signals controlling accumulator fuel pumps are transmitted to pumping control solenoids. Injection signals are controlled to vary fuel delivery rate during an injection event. A back EMF sensing circuit measures valve opening delay and the control system compensates for valve delay. Variable cylinder-specific delays in the injection solenoid output signal pulses are programmed to compensate for a varying fuel line length to each injector nozzle. At startup, the control system pulses the pumping control solenoids to begin pressurizing the accumulator before engine angular position sensors provide an accurate indication of engine angular position to allow precise timed control of the pump. Pressure variations in the high pressure accumulator are monitored by the control system in conjunction with injection events, and pump equipment failures or weaknesses are detected based on the pressure variations. In alternative embodiments of the invention, a pre-biasing current using battery voltage is provided to the injection control valve prior to the desired time of an injection event, and the current is increased at the desired time of opening. An input allows signaling the control system when a load is to be applied to cause an immediate change in fueling levels, to prepare for load increases in electrical generation and other non-motive-power applications.

대표청구항 ▼

An integrated electronic control system for an internal combustion engine fuel injection system in which at least first and second pumping chambers selectively supply fuel to a high pressure accumulator in pumping events of variable duration having a variable starting time and a defined termination

An integrated electronic control system for an internal combustion engine fuel injection system in which at least first and second pumping chambers selectively supply fuel to a high pressure accumulator in pumping events of variable duration having a variable starting time and a defined termination time relative to an angular position of engine rotation, and in which fuel flows from the high pressure accumulator to individual combustion chambers at selected times through a distributor upon activation of an electrically controlled solenoid valve, comprising: engine position sensor means for generating a position signal indicating the angular position of engine rotation relative to a point of reference; accumulator pressure sensor means for generating a pressure signal indicative of fuel pressure in said high pressure accumulator; pressure transfer actuating means for selectively initiating said pumping events transferring fuel to said high pressure accumulator from said first and second pumping chambers, respectively, in response to pump control signals; solenoid valve actuating means for opening said electrically controlled solenoid valve in response to a valve control signal; a control line connected to said solenoid valve actuating means for carrying said valve control signal; control means including memory means for storing a program, and a microprocessor having electrical inputs and outputs and connected to said memory means to read and execute said program, with said control means connected to said engine position sensor means, said accumulator pressure sensor means, said pressure transfer actuating means, and through said control line to said solenoid valve actuating means, for: monitoring said engine rotation angular position and monitoring said accumulator pressure synchronously with said angular position and selectively generating a plurality of said solenoid valve control signals and transmitting said plurality of solenoid valve control signals over said control line at calculated times synchronous with said angular position when injection of fuel into one of the combustion chambers is required, and selectively generating said pump control signals to start said pumping events at calculated times varying relative to an angular position of engine rotation, thus varying the duration of said pumping events to maintain a desired pressure range in said accumulator.