Patent ID: 7455243
Filing Date: 2008-11-25
Classification: F02M

Abstract:
1. A method of operating a fuel injector, comprising the steps of: raising fuel pressure in a nozzle chamber at least in part by energizing a first electrical actuator; opening a single nozzle outlet set of the fuel injector for each of a first injection event, a second injection event and a third injection event respectively at a selected timing at least in part by positioning a needle control valve at a first position that fluidly connects a needle control chamber to a low pressure passage; closing the single nozzle outlet set at a selected timing after the opening step for the first injection event including de-energizing the first electrical actuator to move a pressure control valve to a first position that opens the nozzle chamber to a spill passage while maintaining the needle control valve in the first position; closing the single nozzle outlet set at a selected timing after the opening step for the second injection event including equalizing opening and closing hydraulic pressure forces on a needle valve member to move the needle valve member toward a closed position with a spring force by moving the needle control valve to a second position that fluidly closes the needle control chamber to the low pressure passage before de-energizing the first electrical actuator; closing the single nozzle outlet set at a selected timing after the opening step for the third injection event including equalizing opening and closing hydraulic pressure forces on the needle valve member to move the needle valve member toward the closed position with the spring force by moving the needle control valve to the second position after de-energizing the first electrical actuator.