Patent ID: 7331329

Claim:
A fuel injector comprising: an injector body including a nozzle supply passage always in fluid communication with a needle control chamber via a pressure balancing passage, and the needle control chamber being fluidly connected to a control passage; a direct control needle valve movably positioned in said injector body to open and close a nozzle outlet, and including a closing hydraulic surface exposed to fluid pressure in the needle control chamber and movable to a position that interacts with the control passage to produce a hydraulic stop when the direct control needle valve is in an open position; and a needle control valve attached to said injector body, and including a valve member trapped to move between a low pressure seat corresponding to an off position at which the needle control chamber is fluidly disconnected from a low pressure passage to expose the closing hydraulic surface to high pressure fuel in said needle control chamber, and a high pressure seat corresponding to an on position fluidly connecting the needle control chamber to a low pressure passage to expose said closing hydraulic surface to low pressure fuel in said needle control chamber.