Fuel injector

A fuel injector comprising:

• (a) a hollow elongate nozzle body having a closed distal end portion, said nozzle body having a guide hole, a fuel reservoir chamber provided forwardly of said guide hole, a tapered valve seat formed on an inner surface of the distal end portion of said nozzle body, and a plurality of pairs of first and second injection ports formed in the distal end portion of said nozzle body and spaced from one another in a direction of the periphery of said nozzle body, the angle of said first injection port relative to an axis of said nozzle body being different from the angle of said second injection port relative to the axis of said nozzle body, inner ends of said first injection ports being disposed at said valve seat, inner ends of said second injection ports being spaced from the inner ends of said first injection ports toward the distal end of said nozzle body in the direction of the axis of said nozzle body, and each pair of said first and second injection ports having a common outer end;
• (b) a needle valve received in said nozzle body, said needle valve having a slide portion slidably received in said guide hole, a pressure receiving portion received in said fuel reservoir chamber, and a tapered conical abutment portion formed at a distal end portion of said needle valve, and the inner ends of said first injection ports facing and sealed by an outer peripheral surface of said abutment portion of said needle valve when said abutment portion is seated on said valve seat;
• (c) urging means for urging said needle valve toward said valve seat, said needle valve lifting against the bias of said urging means when a fuel pressure received by said pressure receiving portion of said needle valve exceeds a predetermined pressure, so that said abutment portion is brought out of contact with said valve seat, the injection of fuel from said first injection ports being effected due to a throttle effect between said abutment portion and said valve seat until the amount of lift of said needle valve reaches a specified lift amount, and when the amount of lift of said needle valve exceeds said specified lift amount, said throttling effect being eliminated, so that the injection of the fuel from said second injection ports is effected;
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• (d) lift speed limiting means for lowering the speed of lift of said needle valve until the amount of lift of said needle valve reaches said specified lift amount.