Patent ID: 7677872

Claim:
A fuel pump assembly comprising: a pump bushing containing a dual-chambered pumping cavity that is in fluid communication with a supply of fuel; a first fluid channel connecting a first chamber and a second chamber of the dual-chambered pumping cavity, the first fluid channel allowing an unused portion of the supply of fuel to shuttle between the first chamber and the second chamber; a plunger disposed within the pump bushing and having a primary axis of motion, wherein movement of the plunger in one direction along the primary axis of motion defines an intake stroke of the fuel pump assembly, and wherein movement of the plunger in another direction along the primary axis defines a pressurization stroke of the fuel pump assembly; a plurality of fluid control valves including: a first check valve adapted for inhibiting propagation of a pressure pulsation from the pump bushing to the supply of fuel, wherein the first check valve has an inlet side that is oriented toward the supply of fuel and an outlet side that is oriented toward the first chamber and the second chamber, and wherein the first check valve is adapted to close during the pressurization stroke; a second check valve having an inlet side that is oriented toward the first chamber and an outlet side that is oriented toward a high-pressure fuel line, the second check valve being adapted to open during the pressurization stroke; and an inlet valve adapted for selectively admitting fuel from the first check valve into the first chamber during the intake stroke; and a second fluid channel connecting the outlet side of the second check valve with the inlet side of the first check valve.