Patent US3731303A successfully refreshed from Google Patents.
US3731303A
Expired / Lapsed
US
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Magnetic latching indicator
Assignee: EMICO Inc
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Filing: 1970-05-05
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Granted: 1973-05-01
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Expires: 1990-05-05
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 19:24
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.
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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 |