Fuel injector for use in common rail injection system of internal combustion engine of motor vehicle, has borehole for connection of sealing gap with compression chamber, where guide piece is partially/completely arranged in chamber

摘要

The injector has a piezoelectric actuator (3) arranged in a low pressure chamber (8) such that a piston section (5.1) of small diameter is guided from a coupling chamber (6) into the low pressure chamber by a guide piece (4) for sealing a sealing gap (9) between the piston section and the guide piece. A borehole (10) is arranged in the guide piece for hydraulic connection of the sealing gap with a compression chamber (11) that possesses system pressure, where the guide piece is partially or completely arranged in the compression chamber.