Patent attributes
A fuel injection valve introduces a fuel into an engine and controlling fuel flow to reduce variability between injection events. The fuel injection valve employs an arrangement for a valve nozzle that cooperates with a valve needle to provide a range of needle movement within which the fuel mass flow rate is substantially constant. This can be achieved by providing a restriction with a constant flow area for a predetermined range of needle movement. The method comprises commanding a valve needle to a position within the predetermined range of needle movement to reduce variability in the fuel mass flow rate, particularly when the engine is idling or operating under low load conditions. Valve needle lift is variable during an injection event and from one injection event to another injection event.