Patent ID: 7444990

Claim:
A check valve configured for use in a fuel system including a fuel pump, a fuel rail that receives pressurized fuel from the fuel pump at an operating pressure, and a fuel line fluidly communicating the fuel pump and the fuel rail, the check valve comprising: a body defining a passageway therein, the passageway having an inlet end in fluid communication with the fuel pump and an outlet end in fluid communication with the fuel rail such that pressurized fuel flows in a first fuel-flow direction from the inlet end of the passageway to the outlet end of the passageway during fuel pump operation; a seat coupled to the body; a seal member moveable relative to the seat and selectively engageable with the seat; and a biasing member biasing the seal member toward the seat; wherein the seal member is movable between an unseated position during fuel pump operation, a first seated position in which the seal member is engaged with the seat and the fuel pressure in the fuel rail is substantially equal to the operating pressure after the fuel pump has been turned off, and a second seated position in which the seal member is engaged with the seat and a residual fuel pressure in the fuel rail is substantially less than the operating pressure after the fuel pump has been turned off; and wherein the seal member and the seat define a leak path between the fuel pump and the fuel rail permitting fuel to flow in a second fuel-flow direction opposite the first fuel-flow direction when the seal member is in the second seated position.