Patent ID: 6439204
Filing Date: 2002-08-27
Classification: F02M

Abstract:
A fuel injector unit pump being driven by a cam and functioning to supply fuel to an injector for an injection event, comprising:a body; a pumping plunger reciprocably disposed within the body and comprising a driven end; a cam follower assembly engaging the cam and comprising a cam follower body defining an advance piston bore, an advance piston which engages the driven end of the pumping plunger for advancing or retarding the timing of the injection event, the advance piston being movable in said advance piston bore relative to said follower body in response to fluid pressure controlled by an advance control, said advance piston comprising bleed means for relieving said fluid pressure; a follower return spring disposed between the body and the cam follower assembly; and a plunger return spring nested with the follower return spring and between the body and the advance piston.