Patent ID: 7334741

Claim:
A closed nozzle fuel injector for injecting fuel at high pressure into the combustion chamber of an engine, comprising: an injector body containing an injector cavity and an injector orifice communicating with one end of said injector cavity to discharge fuel into the combustion chamber; a fuel transfer circuit at least partially formed in said injector body to deliver supply fuel to said injector orifice, said fuel transfer circuit including a first circuit and a second circuit in parallel with said first circuit; a nozzle valve element positioned in said injector cavity adjacent said injector orifice, said nozzle valve element movable between an open position in which fuel may flow through said injector orifice into the combustion chamber and a closed position in which fuel flow through said injector orifice is blocked; a rate shaping sleeve mounted on said nozzle valve element for movement between a first position blocking flow through said second circuit and a second position permitting flow through said second circuit, said rate shaping sleeve including a valve surface positioned in sealing contact with said nozzle valve element when said rate shaping sleeve is in said first position to block flow through said second circuit.