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US4660770A Expired / Lapsed US ⏱️ 0.0 years remaining

Electromagnetic fuel injector

Assignee: AIL Corp
•
Filing: 1985-09-25
•
Granted: 1987-04-28
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Expires: 2005-09-25
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Abstract

Abstract An electromagnetically-actuated fuel injector of the type having a spring-biased flat armature and a ball valve element is provided with an improved arrangement for preventing wobble or flutter of the armature, particularly during operation. The armature and ball valve are urged to the closed position by a helical coil spring coaxially aligned with and acting in compression against the armature. The end of the spring in engagement with the armature is modified or formed such that it includes a portion which is inclined axially from a plane normal to the axis of the armature so as to concentrate most of the axial spring force at the location where it engages the armature. As that location is to one side of the axis of the armature, the remote, or opposite, edge of the armature forms a pivot with a stationary part of the injector and reduces or eliminates armature wobble.

Inventors

  • 👤 John H. Gieseking

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 07:34
CPC Classifications
B; B05; B05B; B05B12/00; B05B12/02; B05B12/06; F; F02; F02M; F02M51/00; F02M51/06; F02M51/061; F02M51/0625; F02M51/0635; F02M51/0642; F02M51/0646; F02M51/065; F02M51/08; Y; Y10; Y10S; Y10S239/00; Y10S239/90

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 169 words
In an electromagnetic fuel injector for an internal combustion engine having a valve axis and including a housing, a flat armature connected to a movable valve element arranged to cooperate with a valve seat, spring means for exerting a force in an axial direction on said armature, and electromagnetic means for exerting a force in an opposite direction on said armature when electrically energized, the improvement comprising: said spring means being a helical coil spring disposed in substantially coaxial alignment with the valve axis and having an end in compressive engagement with said armature, the final coil which includes said end of said coil spring being inclined axially outward at an angle relative to a plane normal to the axis of the spring so as to apply to said armature a greater axial spring force to one side of the valve axis than the other thereby to effect pivoting of said armature about a pivot, said pivot being determined by the location of said end of said coil spring.
Claim 2
Dependent Claim 169 words
In an electromagnetic fuel injector for an internal combustion engine having a valve axis and including a housing, a flat armature connected to a movable valve element arranged to cooperate with a valve seat, spring means for exerting a force in an axial direction on said armature, and electromagnetic means for exerting a force in an opposite direction on said armature when electrically energized, the improvement comprising: said spring means being a helical coil spring disposed in substantially coaxial alignment with the valve axis and having an end in compressive engagement with said armature, the final coil which includes said end of said coil spring being inclined axially outward at an angle relative to a plane normal to the axis of the spring so as to apply to said armature a greater axial spring force to one side of the valve axis than the other thereby to effect pivoting of said armature about a pivot, said pivot being determined by the location of said end of said coil spring.
Claim 3
Dependent Claim 15 words
The fuel injector of claim 1 wherein said angle is in the range of 10°-25°.
Claim 4
Dependent Claim 35 words
The fuel injector of claim 1 wherein said spring is initially of the type having both ends squared and in which an end has been subsequently bent outward to provide said end of said spring.
Claim 5
Dependent Claim 54 words
The fuel injector of claim 1 wherein said armature is substantially circular, said electromagnetic means includes a magnetic frame member having an annular portion in axial alignment with the outer circumference of said armature and said pivot is provided by an edge at the circumference of said armature in engagement with said frame member.
Claim 6
Dependent Claim 38 words
The fuel injector of claim 4 wherein said end of said spring engages said armature to one side of said valve axis to provide said greater spring force thereat and said pivot is located substantially diametrically opposite thereto.
Claim 7
Dependent Claim 13 words
The fuel injector of claim 5 wherein said valve element is a ball.

References Cited (Backward Citations)

US1960709A Cited
US4354640A Cited
US4390130A Cited
US4394973A Cited
US4556028A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-04-27 1990-10-27 1991-04-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-04-27 1994-10-27 1995-04-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-04-27 1998-10-27 1999-04-28 $7700.00 Window Closed / Lapsed

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