Patent US2318721A successfully refreshed from Google Patents.
US2840819A
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US
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Reflecting surfaces
Assignee: Westinghouse Electric Corp
•
Filing: 1950-06-20
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Granted: 1958-06-24
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Expires: 1970-06-20
Abstract
No abstract record available.
Inventors
- 👤 Cyril E Mcclellan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:31
CPC Classifications
H; H01; H01Q; H01Q3/00; H01Q3/22; H01Q15/00; H01Q15/14
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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GB585460A
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US2412562A
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US2422189A
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FR952407A
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US2492358A
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US2603749A
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US2577619A
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US2510020A
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US2624003A
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US2538035A
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US2636125A
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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) | 1961-06-23 | 1961-12-23 | 1962-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-06-23 | 1965-12-23 | 1966-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-06-23 | 1969-12-23 | 1970-06-24 | $7700.00 | Window Closed / Lapsed |