EP0141048A1 — Unitized fuel injection system

Claim 1

Independent Claim 364 words

A fuel injection system comprising a fuel rail (10), a fuel pressure regulator (18) connected to one end of the fuel rail (10) and a plurality of fuel injector valves (20.) connected to the fuel rail (10) at predetermined positions there along, wherein each fuel injector valve (20) comprises a generally cylindrical valve housing (80), a metering orifice (100), a stationary valve member (102) having a valve seat (106) disposed at one end of the housing, a movable valve member having an axial valve stem (110) attached to an axially movable armature (116), a stationary coaxial stator (124) separated a predetermined distance from said armature (116), a resilient member (138) disposed between said armature (116) and stator (124) to produce a force urging the end of said valve stem (110) against said valve seat (106), and a coil assembly (126) circumscribing said armature (116) and stator (124) for producing a magnetic force urging said armature (116) against the force of the resilient member (188) towards said stator (124) and unseating said valve stem (110) from said valve seat (106) permitting fuel to flow through said metering orifice (100) characterized in that: said valve housings (80) are tangentially and permanently attached to said fuel rail (10) and are an integral part thereof, each valve housing (80) having a fuel input port (94) interfacing with a mating port in the fuel rail (10) at the point of tangential attachment; said stationary valve member (102) having a conical valve seat (106); said valve stem (110) having a spherical end surface engaging said valve seat (106); said stator (124) axially separated from said armature (116) a distance sufficient so that when said valve stem (110) is fully retracted from said valve seat (106) the fuel flow through said metering orifice (100) is primarily dependent upon the diameter of said metering orifice (100) and independent of the position of the valve stem (110); and said coil assembly (126) having a relief vent (166) connecting a volume enclosed between said armature (116), stator (124) and coil assembly (126) with the remainder of the volume enclosed by the housing permitting a fuel flow therebetween with the movement of said armature (116).

Claim 2

Dependent Claim 364 words

A fuel injection system comprising a fuel rail (10), a fuel pressure regulator (18) connected to one end of the fuel rail (10) and a plurality of fuel injector valves (20.) connected to the fuel rail (10) at predetermined positions there along, wherein each fuel injector valve (20) comprises a generally cylindrical valve housing (80), a metering orifice (100), a stationary valve member (102) having a valve seat (106) disposed at one end of the housing, a movable valve member having an axial valve stem (110) attached to an axially movable armature (116), a stationary coaxial stator (124) separated a predetermined distance from said armature (116), a resilient member (138) disposed between said armature (116) and stator (124) to produce a force urging the end of said valve stem (110) against said valve seat (106), and a coil assembly (126) circumscribing said armature (116) and stator (124) for producing a magnetic force urging said armature (116) against the force of the resilient member (188) towards said stator (124) and unseating said valve stem (110) from said valve seat (106) permitting fuel to flow through said metering orifice (100) characterized in that: said valve housings (80) are tangentially and permanently attached to said fuel rail (10) and are an integral part thereof, each valve housing (80) having a fuel input port (94) interfacing with a mating port in the fuel rail (10) at the point of tangential attachment; said stationary valve member (102) having a conical valve seat (106); said valve stem (110) having a spherical end surface engaging said valve seat (106); said stator (124) axially separated from said armature (116) a distance sufficient so that when said valve stem (110) is fully retracted from said valve seat (106) the fuel flow through said metering orifice (100) is primarily dependent upon the diameter of said metering orifice (100) and independent of the position of the valve stem (110); and said coil assembly (126) having a relief vent (166) connecting a volume enclosed between said armature (116), stator (124) and coil assembly (126) with the remainder of the volume enclosed by the housing permitting a fuel flow therebetween with the movement of said armature (116).

Claim 3

Dependent Claim 30 words

The fuel injector system of Claim 1 wherein said fluid pressure regulator (18) is permanently attached to one end of said fuel rail (10) and is an integral part thereof.

Claim 4

Dependent Claim 20 words

'The fuel injector system of Claims 1 or 2 wherein said valve housings (80) are progressive die formed valve housings.

Claim 5

Dependent Claim 21 words

The fuel injector system of Claim 3 further including a non-magnetic spacer (142) disposed between said armature (116) and stator (124).

Claim 6

Dependent Claim 17 words

The fuel injector system of Claim 4 wherein said spacer (142) is attached to said stator (124).

Claim 7

Dependent Claim 55 words

The fuel injector system of Claim 4 wherein said resilient member (138) is a spring and said stator (124) has a shoulder (140) engaged by one end of said spring, said spacer (142) is a cup shaped member abutting said armature (116) and having a peripheral flange engaged by the opposite end of said spring.

Claim 8

Dependent Claim 38 words

The fuel injector system of Claim 5 wherein said predetermined distance between said armature (116) and stator (124) is sufficient to permit said valve stem (110) to be displaced from said conical valve seat (106) approximately 0.20 millimeters.

Claim 9

Dependent Claim 43 words

The fuel injector system of Claim 1 wherein said predetermined distance between said armature (116) and stator (124) is sufficient to permit the spherical end surface of said valve stem (110) to be displaced from said conical valve seat (106) approximately 0.20 millimeters.

Claim 10

Dependent Claim 45 words

The fuel injector system of Claim 1 wherein said each valve member (20) has an end cap (128) enclosing the other end of said housing (80), said stator (124) is permanently attached to said end cap (128) and supported therefrom coaxial with said armature (116).

Claim 11

Dependent Claim 70 words

The fuel injector system of Claim 4 wherein said resilient member (138) is a return spring and said stator (124) has a shoulder (140) engaged by one end of said return spring, said return spring and the position of said stator's shoulder (140) are preselected at assembly so that said return spring produces a predetermined force urging the spherical end of said valve stem (110) against said valve seat (106).

Claim 12

Dependent Claim 48 words

The fuel injector system of Claim 6 wherein said return spring (138) and the position of said stator's shoulder (140) are preselected at assembly so that said return spring (138) produces a predetermined force urging the spherical end of said valve stem (110) against said valve seat (106).

Unitized fuel injection system

Abstract

Inventors

Bibliographic Details

Claims Analysis

References Cited (Backward Citations)

USPTO Annuity & Maintenance Windows

Assigned Categories & Tags

Assign Category Tag