Fuel injector

摘要

A fuel injector comprising a valve needle (10) which is slidable within a bore (12) and engageable with a seating to control fuel delivery through first and second outlet openings. The valve needle (10) is moveable between a closed position and first and second fuel injecting positions. The fuel injector further comprises a fuel supply passage (18) for supplying fuel under pressure to the bore (12) and a control chamber (38, 40) which is arranged to receive fuel from the fuel passage (18), in use. The valve needle (10) is acted upon in use by a force due to fuel pressure within the control chamber (38, 40). An actuator arrangement (46, 48) controls fuel pressure within the control chamber (38, 40), and damping means (42; 42a, 42b, 42c) are provided for damping movement of the valve needle (10) away from the seating into the first or second fuel injecting position. The supply passage (18) for fuel may be provided with a restricted flow passage (18a) which serves to limit the amplitude of pressure waves within the supply passage (18). <IMAGE>