Patent ID: 7111613

Claim:
A fuel injector for an internal combustion engine, comprising: a plunger reciprocatingly disposed within a bore of the fuel injector to displace fuel from the bore; an electronically controlled spill valve associated with the bore and having a valve element movable between a first position at which the displaced fuel is allowed to drain from the fuel injector, and a second position at which the displaced fuel is retained within the fuel injector and increases in pressure in response to the displacement; a nozzle member having at least one orifice; a valve needle having a base end and tip end, being disposed within the nozzle member, and movable against a spring bias to selectively inject the pressurized fuel through the at least one orifice into the internal combustion engine; and an electronically controlled check valve in fluid communication with the bore and the base end of the valve needle, the electronically controlled check valve having a valve element movable between a first position at which the bore is fluidly communicated with the base end of the valve needle, and a second position at which the base end of the valve needle is fluidly communicated with a drain, wherein: the valve needle is automatically moved to inject the pressurized fuel when the pressure of the fuel within the fuel injector reaches a predetermined valve opening pressure determined by a spring bias; the valve elements of the electronically controlled spill and check valves are both in the second position before the pressure of the fuel within the fuel injector reaches the predetermined valve opening pressure; and the injection terminates when the valve element of the electronically controlled check valve is moved to the first position.