PCT No. PCT / DE98 / 00945 Sec. 371 Date Jun. 30, 1999 Sec. 102(e) Date Jun. 30, 1999 PCT Filed Apr. 3, 1998 PCT Pub. No. WO99 / 15783 PCT Pub. Date Apr. 1, 1999A
fuel injection device for internal
combustion engines is proposed in which a
fuel injection valve is controlled by the pressure in a pressure chamber, which acts on a pressure shoulder in its opening and closing direction. The pressure supply to the a pressure chamber is controlled by a control valve member which in turn is moved by a pressure in a working chamber. The pressure in the working chamber is controlled by a pre-control valve which has a closing body which, through the influence of the piezoelectric drive mechanism, is moved from a second
valve seat to a first
valve seat and thereby momentarily opens a relief line of the working chamber. This movement results in an opening of the control valve member and a supplying of high fuel pressure to the pressure chamber for purposes of injection. Thus a very small pre-injection quantity is produced. In order to produce a main injection quantity, the closing body is positioned in an intermediate position between the valve seats and a longer connection of the high-pressure
fuel supply to the pressure chamber is consequently produced.