Fuel injector for common rail diesel injection for diesel engine, has nozzle needle which has steps in its shaft and damping chamber is formed in area of steps between shaft of nozzle needle and housing wall

摘要

Fuel injector has a nozzle needle (20) which has steps in its shaft, which is formed by the smaller first diameter (d1) and a larger second diameter (d2). A damping chamber (23) is formed in the area of steps between the shaft of the nozzle needle and a housing wall (11). An overflow channel (22) is provided, which connects damping chamber with nozzle area which is fixed below fuel pressure. The nozzle chamber is arranged below the area of the nozzle unit. The overflow channel accordingly the damping chamber can be closed in dependence on the relative position of the nozzle needle.