Engine fuel injector

A method of assembling a fuel injector for use in an engine, comprising the steps of:

• providing an endoskeletal injector tube having an inlet end and an outlet end;
• affixing a valve seat assembly to the outlet end of the tube;
• inserting an injector valve assembly into the inlet end of the tube;
• sliding a coil assembly over the tube;
• sliding a support element over the tube;
• and
• affixing a seal retainer onto the inlet end of the tube, thereby assembling the fuel injector;
• wherein the step of inserting an injector valve assembly further comprises the steps of:
• sliding an injector valve into the inlet end of the tube;
• sliding a magnetic pole into the inlet end of the tube, wherein the pole is adjustable thereafter for setting the stroke of the injector valve;
• and
• affixing the pole within the tube, thereby setting the stroke for the injector valve.

A method of assembling a fuel injector for use in an engine, comprising the steps of:

• providing an endoskeletal injector tube having an inlet end and an outlet end;
• affixing a valve seat assembly to the outlet end of the tube;
• inserting an injector valve assembly into the inlet end of the tube;
• sliding a sealing member over the tube;
• positioning the sealing member into close proximity to the outlet end of the tube;
• sliding a spacer ring over the tube;
• positioning the spacer ring against the sealing member, and thereafter;
• sliding a coil assembly over the tube;
• sliding a support element over the tube;
• and
• affixing a seal retainer onto the inlet end of the tube, thereby assembling the fuel injector.

A fuel injector for use in an engine and comprising:

• a tube enclosing a continuous passage for fuel flow from an inlet end to an outlet end of the tube;
• a valve seat fixed in the outlet end of the tube and including a discharge opening;
• an injection valve including a magnetic armature reciprocably movable in the tube between closed and open positions and biased toward the closed position, said valve engaging the valve seat and closing the discharge opening in the closed position, the valve being spaced from the valve seat and allowing fuel flow out of the discharge opening in the open position;
• a tubular magnetic pole fixed within said tube and engagable by the valve in the open position;
• a solenoid coil mounted on the tube and extending around said pole;
• and
• a magnetic body at least partially enclosing the coil and having upper and lower ends mounted on the tube;
• wherein the body, pole and armature form a magnetic flux concentrating path operative to attract the armature to the pole and open the valve when the coil is energized, and the tube prevents fuel passing therethrough from contacting the coil which actuates the valve.

A fuel injector for use in an engine, comprising:

• an injector body having an axially extending fuel passage therein;
• an injection valve movable in the passage;
• a magnetic pole fixed within the passage of the body;
• a solenoid assembly extending around said pole and at least partially enclosed by said body;
• a valve seat fixed at an outlet end of the passage and having a discharge opening therethrough and a recess opening outward from the discharge opening;
• and
• a director with multiple openings for directing spray delivery from the injector, wherein the director is a cup-shaped member pressed into the recess of the valve seat.

A fuel injector for use in an engine, comprising:

• an injector body having an axially extending fuel passage therein;
• an injection valve movable in the passage;
• a magnetic pole fixed within the passage of the body;
• a solenoid assembly extending around said pole and at least partially enclosed by said body;
• a valve seat fixed at an outlet end of the passage and having a discharge opening therethrough and a recess opening outward from the discharge opening;
• and
• a director with multiple openings for directing spray delivery from the injector, wherein the director is a cup-shaped member pressed into the recess of the valve seat and supplementally fixed within the recess.

A fuel injector for use in an engine and comprising:

• a tube enclosing a continuous passage for fuel flow from an inlet end to an outlet end of the tube;
• a valve seat fixed in the outlet end of the tube and including a discharge opening, said valve seat carrying a director with multiple openings for directing spray delivery from the injector;
• an injection valve including a magnetic armature reciprocably movable in the tube between closed and open positions and biased toward the closed position, said valve engaging the valve seat and closing the discharge opening in the closed position, the valve being spaced from the valve seat and allowing fuel flow out of the discharge opening in the open position;
• a tubular magnetic pole fixed within said tube and engagable by the valve in the open position, the pole being adjustable within the tube prior to being fixed therein for setting the operating stroke of the valve;
• a solenoid coil extending around said pole and included in a separate coil assembly mounted on the tube, the coil assembly including an attached electrical connector and having a central opening through the coil for sliding the coil assembly onto the tube;
• a support element mounted on the tube and having retaining means for connecting the injector to an associated fuel rail and a back-up surface for supporting a seal ring on the tube for insertion in a cup of a fuel rail;
• a seal retainer fixed on said inlet end of the tube and spaced from said back-up surface to form with the tube an annular recess for receiving a seal ring, the seal retainer being adapted for push-on installation on the tube after application of the seal ring;
• and
• a magnetic body at least partially enclosing the coil and having upper and lower ends mounted on the tube;
• wherein the body, pole and armature form a magnetic flux concentrating path operative to attract the armature to the pole and open the valve when the coil is energized, and the tube prevents fuel passing therethrough from contacting the coil which actuates the valve.