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US3731303A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic latching indicator

Assignee: EMICO Inc
•
Filing: 1970-05-05
•
Granted: 1973-05-01
•
Expires: 1990-05-05
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Abstract

Abstract In an indicator having a moving permanent magnet mounted on an arbor, a pointer is mounted on the arbor for rotation independent of the rotation of the moving magnet. This moving permanent magnet engages a projection on the pointer during a portion of its rotation. A control permanent magnet is positioned with its poles lying in the plane of the first permanent magnet poles to latch the moving permanent magnet by repulsion upon rotation in one direction or the other.

Inventors

  • 👤 H Wohlbach

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 17:13
CPC Classifications
G; G08; G08B; G08B5/00; G08B5/22; G08B5/24

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 157 words
An indicator comprising: an indicating element mounted on an arbor, a moving permanent magnet mounted on said arbor for rotation which is independent of the rotation of said indicating element, within fixed limits, means for engagement between said indicating element and said moving permanent magnet said means driving said indicating element during only a portion of the rotation of said moving permanent magnet, said engagement defining said fixed units within which said permanent magnet rotates independent of the rotation of said pointer, an electrically energized operating coil which drives said moving permanent magnet in one rotational direction or the other upon energization with sufficient current, and a control permanent magnet having poles which latch said moving permanent magnet upon rotation in one direction or the other, said permanent magnet being driven past the poles and overcoming the repelling force of said poles in the portion of rotation which is independent of the rotation of said indicating element.
Claim 2
Dependent Claim 157 words
An indicator comprising: an indicating element mounted on an arbor, a moving permanent magnet mounted on said arbor for rotation which is independent of the rotation of said indicating element, within fixed limits, means for engagement between said indicating element and said moving permanent magnet said means driving said indicating element during only a portion of the rotation of said moving permanent magnet, said engagement defining said fixed units within which said permanent magnet rotates independent of the rotation of said pointer, an electrically energized operating coil which drives said moving permanent magnet in one rotational direction or the other upon energization with sufficient current, and a control permanent magnet having poles which latch said moving permanent magnet upon rotation in one direction or the other, said permanent magnet being driven past the poles and overcoming the repelling force of said poles in the portion of rotation which is independent of the rotation of said indicating element.
Claim 3
Dependent Claim 38 words
The indicator recited in claim 1 wherein said control permanent magnet forms one portion of an outer housing for said indicator and wherein another portion of said outer housing is a protective shield constructed of soft magnetic material.
Claim 4
Dependent Claim 51 words
The indicator recited in claim 1 further comprising a flanged bushing projecting through said indicating element said indicating element being positioned on said bushing between said moving permanent magnet and the flange on the bushing so that said magnet and said bushing define the plane of rotation of said indicating element.
Claim 5
Dependent Claim 25 words
The indicator recited in claim 1 wherein said moving permanent magnet is a truncated circle, one side of said truncated circle actuating said engagement means.
Claim 6
Dependent Claim 89 words
The indicator recited in claim 1 wherein rotation of said moving permanent magnet in one direction engages one side with said engagement means after an initial rotation to drive said indicating element to one extreme position, and wherein rotation of the moving magnet in the other direction disengages said one side from the engagement means to allow initial rotation in the other direction before the other side of said moving magnet re-engages said engagement means to drive said indicating element in the other direction to its other extreme position.
Claim 7
Dependent Claim 18 words
The indicator recited in claim 1 wherein said means for engagement includes a projection on said indicating element.
Claim 8
Dependent Claim 28 words
The indicator recited in claim 1 wherein said permanent magnet is positioned with its poles lying approximately in the plane of the poles of the moving permanent magnet.
Claim 9
Dependent Claim 27 words
The indicator recited in claim 7 wherein the poles of said control permanent magnet repel the poles of said moving permanent magnet when in the latched position.

References Cited (Backward Citations)

US2359546A Cited
US2866965A Cited
US3267455A Cited
US3309696A Cited
US3573812A Cited
US3553619A Cited
US3560966A Cited
US3524358A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-04-30 1976-10-30 1977-05-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-04-30 1980-10-30 1981-05-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-04-30 1984-10-30 1985-05-01 $7700.00 Window Closed / Lapsed

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