Patent US3601899A successfully refreshed from Google Patents.
US3601899A
Expired / Lapsed
US
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Single core solid-state compass
Assignee: United States Department of the Navy
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Filing: 1969-07-03
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Granted: 1971-08-31
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Expires: 1989-07-03
Abstract
Abstract A compass with no moving parts, the sensing element consisting of four coils equally spaced around a single toroidal core. Diametrically opposite coils are connected to opposite sides of a center-tapped transformer so that in the absence of an external magnetic field the signals cancel out. The presence of an external magnetic field will then unbalance the coils and produce a directional signal.
Inventors
- 👤 Mahlon R Artz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:46
CPC Classifications
G; G01; G01C; G01C17/00; G01C17/02; G01C17/28; G01C17/30
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
66 words
A compass comprising: a sensing element consisting of four coils equally spaced around a single toroidal core; the four coils connected essentially in parallel whereby the flux from each coil adds to the total flux; means for applying a square wave to the sensing element; means connected to the coils to pickoff any output generated by the coils; and amplifying means connected to the pickoff means.
Claim 2
Dependent Claim
66 words
A compass comprising: a sensing element consisting of four coils equally spaced around a single toroidal core; the four coils connected essentially in parallel whereby the flux from each coil adds to the total flux; means for applying a square wave to the sensing element; means connected to the coils to pickoff any output generated by the coils; and amplifying means connected to the pickoff means.
Claim 3
Dependent Claim
31 words
The compass of claim 1 wherein the pickoff means is two center-tapped transformers, one being connected to the North-South coil pair and the other being connected to the East-West coil pair.
Claim 4
Dependent Claim
38 words
The compass of claim 2 wherein, in the presence of an external magnetic field, the output of each coil pair is a pulse whose amplitude corresponds to a cosinusoidal function of the direction of the external magnetic field.
Claim 5
Dependent Claim
38 words
The compass of claim 3 wherein the output of one coil pair is shifted 90* and added to the output of the other coil pair to produce a signal corresponding to the direction of the external magnetic field.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-30 | 1975-03-01 | 1975-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-30 | 1979-03-01 | 1979-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-30 | 1983-03-01 | 1983-08-31 | $7700.00 | Window Closed / Lapsed |