Patent ID: 7179060
Filing Date: 2007-02-20
Classification: F02M,F04B

Abstract:
1. A pump comprising: a pump housing including a first barrel including a first pumping chamber, and a second barrel including a second pumping chamber; a first plunger positioned to reciprocate in said first barrel; a second plunger positioned to reciprocate in said second barrel out of phase with said first plunger; first and second cams positioned in said pump housing and being operably coupled to move the first and second plungers, respectively; first and second inlet check valves fluidly positioned between a low pressure gallery and said first and second pumping chambers, respectively; a shuttle member having a first hydraulic surface exposed to fluid pressure in said first pumping chamber, and a second hydraulic surface oriented in opposition to said first hydraulic surface and being exposed to fluid pressure in said second pumping chamber; a spill control valve fluidly positioned between said low pressure gallery and a first and second spill passage, which include a common segment between said shuttle valve member and said spill control valve, and said spill control valve being a latching valve with a latching valve member held in a closed position contacting a seat by fluid pressure in one of said first and second pumping chambers; said shuttle member being moveable between a first position in which said first pumping chamber is fluidly connected to said spill control valve and a second position in which said second pumping chamber is fluidly connected to said spill control valve; an electrical actuator operably coupled to said spill control valve, and being operable to move said latching valve member away from said first and second spill passage toward said seat to a closed position when energized; and a spring operably positioned to bias said latching valve member toward said shuttle valve member.