Partial Charging of Single Piston Fuel Pump
AssigneeStanadyne, Inc.
InventorRobert G. Lucas
Life of this patent
Estimating the term…
Abstract
The valve assembly and associated pump, direct a magnetic flux path such that a carefully timed magnetic force is directly applied to an inlet valve member when a coil is energized. As a result, direct actuation of the inlet valve is achieved. This accommodates a new partial charge operating strategy that has a significant benefit to inlet pressure pulsations. The benefit of a partial charging strategy is reduced inlet pulsations and noise, especially during vehicle idle conditions when it is most objectionable.
Claims11
A single piston fuel pump comprising:
- a pumping plunger reciprocally driven in a pumping chamber by a rotating cam, with the pumping chamber subject to intermittent charging of feed fuel by an inlet valve that is either directly coupled to a magnetic field or physically attached to an armature that is directly coupled to a magnetic field;
- and a control system responsive to the angular position of the cam, for controlling the inlet valve by altering the magnetic field to partially charge the pumping chamber before the plunger pressurizes the partially charged fuel while the pumping plunger driven along the nose of the cam.
A fuel pump comprising a pump housing, a fuel inlet connection on the housing for delivering feed fuel into an inlet flow path in the housing;
- a pumping chamber and associated pumping mechanism in the housing for receiving feed fuel from the inlet flow path through an inlet valve assembly, increasing the fuel pressure, and delivering fuel at said increased pressure to a discharge flow path;
- an outlet connection on the housing, in fluid communication with the discharge flow path through an outlet valve;
- wherein the inlet valve assembly includes a valve member directly magnetically coupled to an electromagnetic coil, whereby the coil is selectively energized to generate a magnetic flux path directly through the inlet valve member, thereby applying a magnetic force to said valve member to selectively open and close said valve member against a sealing surface in said inlet flow path;
- and a control system for altering the magnetic field to partially charge the pumping chamber before the pumping plunger pressurizes the partially charged fuel.
A method of controlling feed fuel in a charging phase of a high pressure fuel supply pump through an inlet flow valve assembly, which pump includes
- a cam-driven pumping plunger reciprocable in a pumping chamber;
- a valve assembly inflow path and valve assembly outflow path;
- a magnetic valve member situated in an intermediate position fluidly linking the inflow path and the outflow path;
- a magnetic pole confronting the valve member;
- a selectively energizable coil for generating a magnetic flux directly magnetically coupling the pole and the valve member;
- whereby the valve member opens and closes fluid communication between the inflow path and the outflow path in response to the energized state of the coil;
- and
- wherein said method comprises controlling the magnetic flux to partially charge the pumping chamber before the pumping plunger pressurizes the partially charged fuel while the pumping plunger is driven along the nose of the cam.
(canceled)
Dependencies are inferred from the claim text.