A METHOD FOR OPERATION OF A HYDRAULICALLY ACTUATED FUEL PUMP FOR AN INTERNAL COMBUSTION ENGINE, AND A HYDRAULICALLY ACTUATED FUEL PUMP

摘要

A hydraulically actuated fuel pump (1) for an internal combustion engine has a pump piston (39), which is driven forwards in a delivery stroke by means of an actuator piston (36). Between each injection sequence the pump piston (39) is returned to a fixed starting position by the action of the fuel pressure on the end surface (61, 62) of the pump piston in the pump chamber (52). The delivery volume of the fuel pump is electronically controlled by the supply of hydraulic fluid to the pressure chamber being cut off by the control valve (11) at the moment when the pump piston has delivered the desired volume. The pump cylinder (25) and the actuator cylinder (24) are separate units, which are mutually separated by an intermediate spacing member (26).