Patent attributes
A fuel injector for an internal combustion engine has a nozzle body (36) provided with a nozzle bore (42), an inner valve (16) which is engageable with an inner valve seating (48) to control fuel delivery through one or more first nozzle outlets (38), and an outer valve (18) which is received within the nozzle bore (42) and engageable with an outer valve seating (48) to control fuel delivery through one or more second nozzle outlets (40). An actuator (14) for controlling movement of the inner and outer valves (16, 18) transmits an actuation force to the valves (16, 18) so as to permit either movement of the inner valve (16) only to provide a first injection state in which fuel is delivered through only the or each of the first outlets (38), or movement of the outer valve (18) only to provide a second injection state in which fuel is delivered through only the or each of the second outlets (40). A coupling means (54, 54a, 52d) is provided for coupling movement of the outer valve (18) to the inner valve (16) in circumstances in which the outer valve (18) is moved away from the outer valve seating (48) through an amount exceeding a predetermined threshold amount, thereby to cause the inner valve (16) to lift away from the inner valve seating (48) to provide a third injection state in which fuel is delivered through both the first and the second nozzle outlets (38, 40) together.
