Patent ID: 6830201
Filing Date: 2004-12-14
Classification: F02M

Abstract:
A fuel injector for an internal combustion engine comprising:a pump body defining a cylindrical opening, a piston plunger in the cylindrical opening defining with the cylindrical opening a pumping chamber; a fuel inlet passage and a fuel return passage; a cam follower connected to the piston plunger, the engine having a camshaft that drives the follower during a fuel pumping stroke of the piston plunger; a fuel injection nozzle for fueling the engine; a fuel delivery passage connecting the pumping chamber and the nozzle; a movable control valve communicating with the fuel delivery passage, the control valve having a valve land and a cooperating valve seat defining in part a spill flow path from the fuel delivery passage to the fuel return passage when the control valve is moved in one direction and interrupting the spill flow path when the control valve is moved in the opposite direction; a valve spring for shifting the control valve in the one direction and an electromagnetic actuator for shifting the control valve in the opposite direction; the inlet passage communicating with the pumping chamber through the control valve when the control valve is moved in the one direction whereby the pumping chamber is filled as the piston plunger is retracted following its pumping stroke; and a stop assembly in the pump body adjacent one end of the control valve including a stop body, a stop piston in the stop body engageable with the control valve when it is moved in the one direction to a first stop position of the control valve, the stop piston engaging the stop body when the control valve is moved to a second stop position thereby limiting stroking of the control valve in the one direction; the control valve being separated from the stop piston by a calibrated gap when the valve land engages the valve seat; the control valve being engageable with the stop piston as it is moved to the second stop position without engaging the stop body regardless of misalignment of the stop assembly relative to the control valve.