Abstract: A fuel injector including a filter 30 provided within the tip portion 12 of the injector body 10, down stream of the fuel inlet port 14 and upstream of the spray aperture 14. The filter 30 is in the form of a hollow truncated cone with a base region 32 having an outer diameter dimensioned to be a press fit against the inner sides of the tip portion 12 such that the filter is a press fit within the tip portion. The top or upper region of the cone terminates in an aperture 34 through which the pintle 16 passes, the aperture having an inner diameter dimensioned to be a close sliding fit over the pintle 16.

Abstract: An electromagnetic fuel injector comprises a body having a fuel inlet and a fuel outlet and a base comprising a valve seat sealably connected to the body. A disk-shaped armature disposed at the fuel outlet for controlling the flow of fuel has an upper surface and a lower surface that comprises a sealing interface with the valve seat. A ring-shaped flexural element comprising a plurality of spaced flexural legs is in contact with the injector body and the upper surface of the armature and provides a spring bias between the body and armature upper surface. When the injector is closed, spring bias between the body and armature upper surface maintains the armature in a sealing position with the valve seat, and when the injector is open, increased spring bias between the body and armature upper surface impels the armature to return to a sealing position with the valve seat.

Abstract: A fuel injector includes a flexural element connected to a valve armature for restricting radial movement of the armature within a fuel passage. The flexural element is flat and exerts no force on the valve when it is closed but is flexed when the valve is opened and supplements the valve spring force during closing of the valve. The flexural element also is used to set the valve stroke length equal to the element's thickness. A flat tool presses a valve ball into the armature while the ball is seated on a valve seat until the flexural element engages a seat related surface. Engagement of the tool with the flexural element fixed to the armature assures that the flexural element is in an unloaded flat position when the valve is closed and establishes the valve stroke when the valve assembly and seat are installed in the injector body.

Abstract: The present invention is directed to a fuel injector for an internal combustion engine wherein components external to the tubular body are positioned, joined, and retained on the body, and wherein the tubular body is structurally reinforced, by being encapsulated together in a molded shroud formed of a structural adhesive polymer.

Abstract: A method is provided for assembling a pole piece into an internal fuel passage of a fuel injector. The assembly method includes the steps of: (a) providing an endoskeletal injector tube, where the injector tube provides the fuel passage for the fuel injector; (b) forming at least one depression into an outer surface of the injector tube; (c) inserting an injector valve into the injector tube; (d) inserting the pole piece into the injector tube, wherein the pole piece is adjustable thereafter; and (e) affixing the pole piece within the injector tube, where an outer surface of the pole piece is in contact with an inner surface of the injector tube corresponding to the depressions, thereby creating a spring fit between the pole piece and the tube.

Abstract: A fuel injector for an engine includes a continuous endoskeletal injector tube enclosing an imperforate continuous passage for fuel flow from an inlet end to an outlet end of the tube. A valve seat, injection valve, tubular magnetic pole, biasing spring and adjusting sleeve are mounted within the tube, optionally with other elements, all being exposed to fuel in the passage defined by the tube. A solenoid coil and a magnetic body together with mounting components and seals are mounted on the exterior of the tube where they are protected from exposure to the fuel, which is restricted to passage within the continuous tube. 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. The solenoid coil may be preassembled with its connector in a body forming a separate coil assembly for subsequent installation on the injector tube.

Abstract: A fuel injector includes a tubular injector body which has an open, upper end and defines an axial fuel passage. A solenoid actuator assembly is disposed in the injector body and includes a spool-like bobbin with a central through-bore and a wound wire coil supported thereon. A magnetic circuit pole subassembly includes a fuel tube, a valve guide, and a pole piece. The fuel tube has a tubular portion and a lower circular flange portion radially extending from a lower terminal end of the tubular portion to contact the open, upper end of the injector body. The nonmagnetic valve guide has a guide cylindrical portion, extending axially downward through the central throughbore and is closely encircled by the bobbin, and a guide circular flange portion radially extending from an upper end of the guide cylindrical portion and mating with the lower circular flange portion of the fuel tube.

Abstract: The present invention relates to a fuel injector for delivery of fuel to an internal combustion engine comprising an injector body and a fuel discharge opening having a valve seat extending thereabout. A valve element is normally seated on the valve seat to close the fuel discharge opening and is operable to move inwardly off of the valve seat to open the fuel discharge opening allowing fuel to pass through. An annular valve guide is seated upstream of the valve seat in spaced relationship thereto and extends about the valve element to guide it as the valve element moves relative to the valve seat. The valve guide has fuel passages to pass fuel. An annular filter shelf located in the injector body, extends circumferentially about the valve seat intermediate of the valve guide and the valve seat.

Abstract: A fuel injector for discharging fuel to an internal combustion engine is disclosed. The injector includes a nozzle body having a solenoid actuator, a pole piece with an axial extending fuel passage, a valve assembly including a reciprocably moveable armature operable against the bias of a spring member, a calibration tube extending through the pole piece fuel passage and operable to load the spring, an axially extending, drawn metal fuel tube having a first end defining an injector fuel inlet and a second end in communication with the axially extending fuel passage of the pole piece. The fuel tube includes features which extend radially inwardly in the wall of the fuel tube to define depressions in the outer surface of the wall which function, with a molded composite jacket to deter rotation of the tube.