Direct Injection Pump Control Strategy For Noise Reduction

摘要

A pump may have a first chamber and a solenoid coil to control movement of a first valve member. A second chamber may have a second valve member to control fluid moving into a third chamber. A first fluid passageway may link the first and second chambers, a second passageway may link second and third chambers and a third passageway may link third and fourth chambers. After pressurizing the third chamber causing fluid to flow into and leave a fourth chamber, the third chamber depressurizes due to downward movement of a plunger. Upon depressurization with a solenoid coil energized, second valve member floats and then moves against a valve seat. While the second valve member is moving toward the valve seat, the solenoid coil is de-energized causing the first valve member to move and strike the second valve member when the second valve member is moving at maximum velocity.

主权项

1. A method of controlling a pump, comprising:
providing the pump with a casing that defines a first chamber, a second chamber, a third chamber and a fourth chamber; providing a fluid inlet in the first chamber and a fluid outlet in the fourth chamber; providing a first movable valve member in the first chamber and a second movable valve member in the second chamber; providing a third movable valve member in the fourth chamber; providing a solenoid coil; during a suction stroke of the pump, moving a plunger in the third chamber away from the third chamber so that a volume of the third chamber increases to move the second valve member toward a stop and to cause the second valve member to collide against the stop; moving the third valve member against a valve seat to prevent fuel from exiting through the fluid outlet; during a pumping stroke of the pump, energizing the solenoid coil a first time to attract the first movable valve member toward the solenoid coil; moving the second movable valve member against a second valve seat; maintaining energizing of the solenoid coil before and after a top dead center position of the plunger and then de-energizing the solenoid coil during the suction stroke.