Patent ID: 6776139
Filing Date: 2004-08-17
Classification: F02B,F02M

Abstract:
A fuel injector for an internal combustion engine having at least one air-fuel combustion chamber, the fuel injector including a fuel injection nozzle assembly for injecting fuel into the combustion chamber during an injection event for each engine cycle, an engine-driven injector pump for developing injector pressure for distribution to the nozzle assembly and a control valve assembly for controlling fuel delivery to the nozzle assembly, the control valve assembly comprising:a pair of control valves in a nozzle pressure feed passage, the feed passage extending from a high pressure pumping chamber of the injector pump to the nozzle assembly; a low pressure fuel spill passage communicating with one control valve of the pair, the one control valve opening communication between the nozzle feed passage and the low pressure spill passage when it is moved toward an open position and closing communication between the nozzle feed passage and closing communication between the nozzle feed passage and the low pressure spill passage when it is moved toward a closed position whereby pressure pulses with controlled timing are developed during an injection event; the nozzle assembly including injection orifices and a needle valve element for controlling opening and closing of the injection orifices to establish controlled fuel injection rate and pressure pulse timing; a second control valve of the pair opening and closing communication between the nozzle feed passage and the needle valve element as the second control valve is actuated between an open position and a closed position whereby the timing of the pressure pulses and the shape of a pressure time trace for the one control valve are modified by the second control valve; and a single solenoid actuator for the one control valve and the second control valve, the solenoid actuator comprising a single stator with solenoid windings and at least one armature adjacent the windings whereby the armature is subjected to electromagnetic forces when the windings are energized to develop a magnetic flux field; the armature developing control valve actuating forces on the control valves when the windings are energized whereby pressure pulse timing and fuel injection rate are controlled.