Delphi Technologies, Inc.

Lucas Industries Limited

Robert Stephen Bond

Daniel Jeremy Hopley

William Robert Burborough

An advance arrangement for use in controlling timing of fuel delivery by a fuel pump comprises an advance piston which is moveable within a first bore and which cooperates, in use, with a cam arrangement of a fuel pump to adjust the timing of fuel delivery by the pump, a surface associated with the advance piston being exposed to fuel pressure within an advance piston control chamber. The advance arrangement also includes a servo-piston which is slidable within a further bore provided in the advance piston to control the pressure of fuel within the advance piston control chamber, a surface associated with the servo-piston being exposed to fuel pressure within a servo control chamber. A non-drift arrangement, in the form of a drilling on or in the advance piston, is provided for preventing fuel pressure variations in the advance piston control chamber which would otherwise occur due to fuel leakage into or out of the advance piston control chamber whilst the servo control piston remains in a substantially fixed position. The advance arrangement may also include a damping arrangement for damping movement of the servo-piston in a direction to retard timing which occurs as a result of movement of the advance piston in a direction to advance timing at the end of a pumping event.

Advance arrangement

A pressure regulator for use with a low pressure fuel pump comprises a pressure relief valve connected between the inlet and outlet of the pump to permit fuel flow from the outlet to the inlet upon the pressure difference therebetween exceeding a predetermined level, and an accumulator independent of the pressure relief valve communicating with the outlet of the pump.

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Challock, United Kingdom

Robert Stephen Bond