Fuel injection device for an internal combustion engine comprises a filling chamber connected to a fuel feed line and arranged at each of the ends of two pistons facing away from an actuator

摘要

Fuel injection device (1) comprises an injection valve (9), a control valve (41) controlling the pressure in a control chamber (43) and having a moving valve part (51) operated by an actuator (31) via a hydraulic coupler (35) having two pistons (36, 37) arranged behind each other and interacting with a coupler volume of the coupler, and devices for filling the coupler volume with fuel under pressure via guide gaps (65, 67) of the pistons. A filling chamber (80, 81) connected to a fuel feed line (5) is arranged at each of the ends of the pistons facing away from the actuator. One of the pistons with a cross-sectional area at its end facing the actuator is mechanically coupled to the actuator via a rod (61) with a smaller cross-sectional area. The other piston with a cross-sectional area operates the control valve at its end facing away from the actuator via a rod (63) with a smaller cross-sectional area. The two ends of the pistons facing the actuator engage in associa ted combination chambers (82, 83) which are connected via a channel (84). The direction of the opening movement of the moving valve part coincides with the direction of the fuel flowing out of the control chamber so that a force compensation is at least partly achieved for the control valve because of the pressure acting on the other piston in its combination chamber.