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US4227100A Expired / Lapsed US ⏱️ 0.0 years remaining

Dual output force motor

Assignee: Schneider Electric Systems USA Inc
•
Filing: 1979-02-26
•
Granted: 1980-10-07
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Expires: 1999-02-26
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Abstract

Abstract An electric force motor includes two movable and independently actuatable coils energized by a single magnetic circuit. Air gaps are formed at respective ends of a tubular permanent magnet between a core of magnetically permeable material mounted within the magnet and pole pieces attached to opposite ends of the magnet. Such a configuration thus establishes a serial magnetic circuit connecting the magnet and the core through each of the air gaps. The two coils, each positioned within the respective air gaps, receive independent electrical input signals to develop corresponding output forces. Interactions between each coil that would tend to affect accuracy are minimized by choosing a magnet of high coercivity and by limiting the amount of input current applied to each coil.

Inventors

  • 👤 Frederick D. Ezekiel
  • 👤 Alf L. Carroll, Jr.

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 16:07
CPC Classifications
H; H02; H02K; H02K41/00; H02K41/02; H02K41/035; H02K41/0352; H02K41/0354; H02K41/0356; G; G01; G01D; G01D5/00; G01D5/12; H02K16/00; H02K16/02

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 161 words
An electrical force motor comprising: an elongate tubular structure of magnetic material; an elongate cylindrical structure of magnetic material positioned within said tubular structure and spaced therefrom; pole piece means attached to opposite ends of said structures forming coaxial circular air gaps of equal diameter and width at the respective ends; one of said structures including permanent magnet means establishing a single magnetic flux path which serially passes through both said tubular and cylindrical structures and across each air gap at the respective ends of said structures; first and second movable coils of equal diameter positioned within said air gaps respectively and adapted to be actuated by independent electrical signals; said permanent magnet means being formed of a material exhibiting high coercive forces that are sufficient to substantially minimize the effect on the output force of one coil that is produced by an electrical signal applied to the other of said coils, whereby said coils may develop corresponding non-interactive output forces.
Claim 2
Dependent Claim 161 words
An electrical force motor comprising: an elongate tubular structure of magnetic material; an elongate cylindrical structure of magnetic material positioned within said tubular structure and spaced therefrom; pole piece means attached to opposite ends of said structures forming coaxial circular air gaps of equal diameter and width at the respective ends; one of said structures including permanent magnet means establishing a single magnetic flux path which serially passes through both said tubular and cylindrical structures and across each air gap at the respective ends of said structures; first and second movable coils of equal diameter positioned within said air gaps respectively and adapted to be actuated by independent electrical signals; said permanent magnet means being formed of a material exhibiting high coercive forces that are sufficient to substantially minimize the effect on the output force of one coil that is produced by an electrical signal applied to the other of said coils, whereby said coils may develop corresponding non-interactive output forces.
Claim 3
Dependent Claim 38 words
Apparatus as claimed in claim 1 wherein said tubular structure comprises an axially-magnetized permanent magnet; said cylindrical structure being formed of magnetically permeable material and serving as a return path for the flux generated by said permanent magnet.
Claim 4
Dependent Claim 15 words
Apparatus as claimed in claim 2 wherein said permanent magnet is formed from Alnico 8.

References Cited (Backward Citations)

US2931925A Cited
US3018467A Cited
US3924146A Cited
US4075517A Cited
US4136293A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-10-07 1984-04-07 1984-10-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-10-07 1988-04-07 1988-10-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-10-07 1992-04-07 1992-10-07 $7700.00 Window Closed / Lapsed

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