US3860931A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ship-borne gravity stabilized antenna
Assignee: Post Office
•
Filing: 1973-11-26
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Granted: 1975-01-14
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Expires: 1993-11-26
Abstract
Abstract A gimballed-platform-mounted antenna arrangement for semistabilizing the orientation of the antenna of said arrangement on a ship, said arrangement being semi-stabilized in use by means of its having a long natural period of oscillation and a high moment of inertia as hereinbefore defined.
Inventors
- 👤 Donald Geoffrey Pope
- 👤 Rodney John Kirkby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:07
CPC Classifications
H; H01; H01Q; H01Q1/00; H01Q1/12; H01Q1/18
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
157 words
A system for semi-stabilizing orientation of a directional receiving antenna of an antenna arrangement of a ship, wherein said system comprises: a structure having a mass of M kg and including said antenna balanced about a point fixed with respect to said structure; bearing means which define axes of rotation for said structure, which axes intersect at a pivotal center; and a radome covering said structure; said structure being, in use, gimbally mounted pendulously upon said ship by said bearing means with the center of gravity of saId structure located below said pivotal center and spaced therefrom by a distance which, in meters, does not exceed 0.002 times the minimum value of the quotient I/M, where Ikg m2 is the moment of inertia of said structure about any of said axes, and said bearing means has a maximum total Coulomb friction torque about any of said axes which, in Newton-meters, is not greater than 0.00075 X I.
Claim 2
Independent Claim
157 words
A system for semi-stabilizing orientation of a directional receiving antenna of an antenna arrangement of a ship, wherein said system comprises: a structure having a mass of M kg and including said antenna balanced about a point fixed with respect to said structure; bearing means which define axes of rotation for said structure, which axes intersect at a pivotal center; and a radome covering said structure; said structure being, in use, gimbally mounted pendulously upon said ship by said bearing means with the center of gravity of saId structure located below said pivotal center and spaced therefrom by a distance which, in meters, does not exceed 0.002 times the minimum value of the quotient I/M, where Ikg m2 is the moment of inertia of said structure about any of said axes, and said bearing means has a maximum total Coulomb friction torque about any of said axes which, in Newton-meters, is not greater than 0.00075 X I.
Claim 3
Dependent Claim
15 words
An antenna arrangement according to claim 1 wherein said bearing means comprises a universal joint.
Claim 4
Dependent Claim
17 words
An antenna arrangement according to claim 2 wherein said universal joint is of the constant velocity type.
Claim 5
Dependent Claim
23 words
An antenna arrangement according to claim 1 including means for adjusting the location of said center of gravity relative to said pivotal centre.
Claim 6
Dependent Claim
24 words
An antenna arrangement according to claim 1 wherein said total Coulomb friction torque is of substantially the same magnitude about all of said axes.
References Cited (Backward Citations)
US1260181A
Cited
US1569325A
Cited
US2477574A
Cited
US2599381A
Cited
US2901208A
Cited
US3789414A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-13 | 1978-07-15 | 1979-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-13 | 1982-07-15 | 1983-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-13 | 1986-07-15 | 1987-01-14 | $7700.00 | Window Closed / Lapsed |