Abstract: An engine fuel injector body is assembled using a furnace brazing method to provide structural and hermetic internal joints at interior locations with minimum size and processing. The method of assembling an injector with such an internal hermetic and structural joint may include the steps of providing an annular body member with an annular inner recess having an inner cylindrical surface, forming an annular end recess adjoining the cylindrical surface, fitting a tubular member into the inner recess of the body member with an outer surface of the tubular member engaging the cylindrical surface of the inner recess, placing a brazing ring in the end recess of the body member adjacent the tubular member, and furnace brazing the members together to form the internal hermetic and structural joint. Additional joints may be joined during the same brazing step.

Abstract: A fuel cell system and a method of using a pressure regulator in a fuel cell system are disclosed herein. The method comprises controlling a purge gas pressure of a purge gas disposed in an enclosure disposed around a fuel cell stack and a waste energy recovery assembly, by seating a pressure plunger in a seating portion of a pressure regulator, wherein the purge gas unseats the pressure plunger when the purge gas pressure exceeds a desired pressure. The method further comprises passing a sufficient amount of the purge gas past the seating portion to reduce the purge gas pressure to at least the desired pressure.

Abstract: A cover for use with a fuel injector. The cover formed of at least two separate pieces that are assemble over the fuel injector. The pieces are held together by a detent member and cooperate to form a cavity that houses the fuel injector. A complaint member is positioned within the cavity to minimize relative movement between the cover and the fuel injector.

Abstract: A method of assembly of a fuel injector having a valve plunger reciprocable in a guide tube for movement from a closed position engaging a valve seat to an open position engaging a valve stop by energizing of a solenoid coil to move the plunger against a biasing spring, wherein the method includes setting the valve stop at a position effective to establish the desired valve stroke, and fixing the valve stop to the guide tube by first laser spot welding the valve stop in the guide tube to fix the position of the valve stop without changing the set gap, and then laser seam welding the valve stop in the guide tube at an axial location beyond the spot welds, relative to a plunger-engagable end of the valve stop, to provide a hermetic seal around the valve stop.

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 is provided for use in an internal combustion engine. The fuel injector includes an injector body having an axially extending fuel passage for fuel flow, an injection valve movable in the passage for controlling fuel flow therein, a valve seat adjustably positioned into an outlet end of the fuel passage, and a valve seat retainer for applying an axial load onto the valve seat and securely attaching the valve seat into the fuel passage of the injector body.

Abstract: An injector valve armature/spacer is formed as an integral tri-function multiple thickness member for an engine fuel injector. The member includes an armature having a center portion with an upper side engagable by a biasing spring and an outer portion with spaced radial openings extending outward from the center portion. An outer rim is connected to the inner portion of the armature by flexible legs extending radially through the radial openings. The rim has a thickness greater than that of the armature by a differential dimension establishing a stroke of the armature. The legs have a thickness less than that of the armature to permit flexing of the legs upon movement of the armature. The integral member is designed for manufacture in multiple layers using electroforming, optionally combined with metal etching.

Abstract: A method for locating an injector ball valve guide in alignment with a valve seat mounted in a common recess of an injector valve body. The valve guide is a disk that has a central opening which guides a valve ball of an associated valve member. During assembly, the guide disk is aligned with the valve seat by a locating tool having an oversized ball on a load rod. The oversized ball is fitted closely within the central opening of the guide and is seated on the ball seat to align the seat and opening. The valve seat and guide disk are then locked in the recess by crimping edges of the recess against the valve seat. The locating tool is removed and assembly of the remaining injector components is completed. The method simplifies alignment of the seat and guide components. In a variation of the method, the guide is aligned with and fixed to the valve seat with the oversized ball in place to form an aligned subassembly for subsequent installation into a fuel injector.

Abstract: An engine fuel injector (10) having a fuel inlet tube (12) and a biasing spring (56) loading a solenoid actuated injection valve (50) within the injector (10) is provided with a calibration assembly (58) combining the calibration member (74) or tube with an internally mounted fuel inlet filter (76). The calibration member (74) may include a body (78) with an enlarged end (88) that is interference fitted within the fuel inlet tube (12) and an opposite stepped in end (80) forming a seat (82) which is engaged by the biasing spring (56). The fuel filter (76) has an enlarged annular base (92) fixed within the enlarged end (88) of the calibration member (74) and having an associated filter screen (98) or element through which fuel passing through the calibration member is filtered for passage through the injector (10).

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.