Patent ID: 6196193
Filing Date: 2001-03-06
Classification: F02D,F02M

Abstract:
A fuel injection device for internal combustion engines, comprising a high-pressure fuel source (5, 8) that is connected to a fuel injection valve (14), said fuel injection valve has an injection valve member (21) for controlling an injection opening (25) and has a control chamber (36), said control chamber is defined by a movable wall (34) which is at least indirectly connected to the fuel injection valve member (21), and with an inlet conduit (53) through which fuel from a high-pressure source (8) communicates with the control chamber (36), and with an outflow conduit (57) by way of which the control chamber (36) is connected to a relief chamber (6), wherein the above-mentioned connections to and from the control chamber are controlled by way of a valve (40), which has a valve member (43) with a closing body (42) that is disposed so that the closing body moves coaxial to first and second valve seats (54, 55) in a valve chamber (41), the valve chamber continuously communicates with the control chamber (36) by way of a conduit (37) and with a tappet (45) that is moved by an electrically actuated drive mechanism (59), by means of the drive mechanism the closing body (42) is moved between the first and second valve seats (54, 55) and is guided in a guide bore (50) that coaxially adjoins one of the first and second valve seats (54, 55), wherein between the first valve seat (54), the tappet (45, 48) and the guide bore (50), a through flow conduit (51) is embodied in the housing (19) of the valve and is connected to the outflow or inflow conduit and, adjacent to the second valve seat (55), the inflow or outflow conduit continues coaxially, and a throttle (58, 60) that controls the through flow is disposed in at least one of the conduits (53, 57), a piezoelectric element or a magnetostrictive element is provided as the drive mechanism (59) of the tappet (45), of the drive mechanism excitation can be controlled so that the valve body (42) assumes a position in which one of the first and second valve seats (54, 55) is completely opened or completely closed, or assumes an intermediary position in which both of the valve seats (54, 55) are open in a controlled manner and the control chamber (36) experiences a partial relief by means of which the injection valve member (21) is moved into a partially open position.