Fuel-injection system for internal combustion engines

A fuel injection apparatus (1) for internal combustion engines with a high-pressure fuel source (1) from which fuel is supplied to an injection opening (7) by means of a control valve (6), which can be actuated by a piezoelectric unit (9), where the control valve (6) has a valve member (8), which is disposed in a valve body (10) and can be moved axially with a valve head (12) between a first valve seat (13) and a second valve seat (14), which define a first valve chamber (15);

• a line (5) conveying fuel from the high-pressure fuel source (1) feeds into a second valve chamber (16), which is defined by the first valve seat (13) and a first guide (18) of the valve member (8) in the valve body (10);
• a line (22), which leads to the injection opening (7), branches from the first valve chamber (15);
• a second guide (28) of the valve member (8) is provided in a region of the valve member (8) adjacent to the second valve seat (14);
• a respective leakage line (21, 30) is provided on the side of each of the guides (18, 28) remote from the first valve chamber (15);
• and the diameters of the valve seats (13, 14) and the guides (18, 28) are respectively selected to be the same so that a force compensation is achieved in the control valve (6).