Patent US2708472A successfully refreshed from Google Patents.
US4055901A
Expired / Lapsed
US
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Gyrocompass
Assignee: Tokyo Keiki Inc
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Filing: 1976-01-19
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Granted: 1977-11-01
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Expires: 1996-01-19
Abstract
Abstract A gyrocompass including first and second follow-up means wherein the second follow-up means corrects for various errors without effecting the accuracy of the gyrocompass which eliminates the need of expensive correction signal generators used in the prior art.
Inventors
- 👤 Susumu Ishii
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 01:36
CPC Classifications
G; G01; G01C; G01C19/00; G01C19/02; G01C19/34; G01C19/38
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
207 words
A gyrocompass comprising, a housing, a follow-up ring, vertical shafts attached to said follow-up ring and rotatably supported by said housing to rotate about a vertical axis, a directional gyro case including a rotor supported by said follow-up ring by a gimbel system mounted thereon and adapted to indicate direction, a first electrical pick-up having a null position mounted on said gyro case and said gimbel system in opposed relationship to detect relative movement therebetween about said vertical axis, a first servo motor mounted on said housing to receive a signal from said first pick-up, said first servo motor operatively connected to said follow-up ring to drive it until the output of said first electrical pick-up indicates its null position, a first gear rotatably mounted on one of said vertical shafts attached to said follow-up ring, a compass card attached to rotate with said first gear, a second electrical pick-up having a null position mounted to detect displacement between said first gear and said one vertical shaft, and a second servo motor mounted on said housing and receiving the output of said second electrical pick-up and operatively connected to drive said first gear to reduce the output of said second electrical pick-up to indicate its null position.
Claim 2
Dependent Claim
207 words
A gyrocompass comprising, a housing, a follow-up ring, vertical shafts attached to said follow-up ring and rotatably supported by said housing to rotate about a vertical axis, a directional gyro case including a rotor supported by said follow-up ring by a gimbel system mounted thereon and adapted to indicate direction, a first electrical pick-up having a null position mounted on said gyro case and said gimbel system in opposed relationship to detect relative movement therebetween about said vertical axis, a first servo motor mounted on said housing to receive a signal from said first pick-up, said first servo motor operatively connected to said follow-up ring to drive it until the output of said first electrical pick-up indicates its null position, a first gear rotatably mounted on one of said vertical shafts attached to said follow-up ring, a compass card attached to rotate with said first gear, a second electrical pick-up having a null position mounted to detect displacement between said first gear and said one vertical shaft, and a second servo motor mounted on said housing and receiving the output of said second electrical pick-up and operatively connected to drive said first gear to reduce the output of said second electrical pick-up to indicate its null position.
Claim 3
Dependent Claim
33 words
A gyrocompass according to claim 1 including a signal generator mounted on said housing and being operatively driven by said first gear, and an indicator connected to said signal generator to indicate azimuth.
Claim 4
Dependent Claim
27 words
A gyrocompass according to claim 1 including a correction circuit connected between said second electrical pick-up and said second servo motor for correcting speed and latitude errors.
Claim 5
Dependent Claim
205 words
In a gyrocompass comprising a housing, a gyro case, a gimbal supporting the gyro case, a follow-up shaft, a follow-up ring rotatably supported by said housing to rotate about a vertical axis on said follow-up shaft, and said gimbal is mounted within the follow-up ring, a first follow-up system including detecting means mounted on the gimbal support and the gyro case to detect a relative movement therebetween about the vertical axis, the improvement comprising a second follow-up detecting means mounted to said housing and said follow-up shaft, wherein said second follow-up detecting means includes a first gear rotatably mounted on said follow-up shaft, a signal generator mounted on said housing and having a rotary shaft, an indicator connected to said signal generator, a second gear in mesh with said first gear, and said rotary shaft of said signal generator fixed to said second gear, a pick-up mounted for detecting a displacement between said follow-up shaft and said first gear, a third gear in mesh with said first gear, a servo motor mounted on said housing and its rotary shaft fixed to said third gear and supplied the output from said pick-up and driving said first gear and a compass card attached to said first gear.
Claim 6
Dependent Claim
205 words
In a gyrocompass comprising a housing, a gyro case, a gimbal supporting the gyro case, a follow-up shaft, a follow-up ring rotatably supported by said housing to rotate about a vertical axis on said follow-up shaft, and said gimbal is mounted within the follow-up ring, a first follow-up system including detecting means mounted on the gimbal support and the gyro case to detect a relative movement therebetween about the vertical axis, the improvement comprising a second follow-up detecting means mounted to said housing and said follow-up shaft, wherein said second follow-up detecting means includes a first gear rotatably mounted on said follow-up shaft, a signal generator mounted on said housing and having a rotary shaft, an indicator connected to said signal generator, a second gear in mesh with said first gear, and said rotary shaft of said signal generator fixed to said second gear, a pick-up mounted for detecting a displacement between said follow-up shaft and said first gear, a third gear in mesh with said first gear, a servo motor mounted on said housing and its rotary shaft fixed to said third gear and supplied the output from said pick-up and driving said first gear and a compass card attached to said first gear.
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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) | 1980-10-31 | 1981-05-02 | 1981-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-31 | 1985-05-02 | 1985-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-31 | 1989-05-02 | 1989-11-01 | $7700.00 | Window Closed / Lapsed |