Patent attributes
A fuel injector having an injection nozzle comprising a nozzle body being provided with a nozzle bore, an outer valve received within the nozzle bore and being engageable with a first seating to control fuel delivery through a first set of one or more nozzle outlets. The outer valve is provided with an outer valve bore within which an inner valve is received the inner valve being engageable with a second seating to control fuel delivery through a second set of one or more nozzle outlets. The fuel injector further includes an injection control chamber for fuel and pressure control means for controlling the pressure of fuel within the injection control chamber. A first surface associated with the inner valve and a second surface associated with the outer valve are exposed to fuel pressure within the injection control chamber, wherein the first and second surfaces are arranged such that when the pressure of fuel within the injection control chamber is increased to a relatively high pressure, one of the outer valve or the inner valve is caused to disengage its respective seating and when the pressure of fuel with the injection control chamber is reduced to a relatively low pressure, the other of the outer valve or the inner valve is caused to disengage its respective seating.
