Fuel injection valve for vehicle of common rail type, has three way valve and main and secondary apertures to connect channels to high or low pressure lines according to valve position

摘要

The valve (10) has a control chamber (3) for a nozzle needle (2). A three way valve (4) has a valve body (41) driven by a piezoelectric drive unit (5). First (22) and second (23) channels connect first (43) and second (44) valve connections to low (17) and high (15) pressure lines, respectively. A third channel (24) is connected to a main aperture (61) to connect a third valve connection (45) to the control chamber. A fourth channel (25) is connected to a secondary aperture (62) to connect the control chamber to the high pressure line. If the first connection is open and the second connection is shut, the control chamber is connected to the low-pressure line through the third channel, the valve chamber and the first channel. If the first connection is closed and the second connection is open, the control chamber is connected to the high pressure line through the third channel, the valve chamber and the second channel.