Patent ID: 6406269
Filing Date: 2002-06-18
Classification: F02M

Abstract:
A fuel pump comprising a pumping plunger reciprocable within a plunger bore under the action of a cam drive arrangement, the cam drive arrangement comprising:first and second surfaces defining therebetween a chamber, the volume of which can be controlled to control the spacing of the first and second surfaces, thereby permitting control of the axial length of the cam drive arrangement; wherein the first surface is defined by a tappet member which acts to transmit a force from the cam drive arrangement to the pumping plunger; wherein the second surface is defined by a piston member slidable within a tappet bore formed in the tappet member; wherein the tappet member is shaped to define, at least in part, a relief passage which communicates with the chamber upon movement of the piston member beyond a predetermined position.