Patent US2490030A successfully refreshed from Google Patents.
US2490030A
Expired / Lapsed
US
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High-frequency tube structure
Assignee: Unisys Corp
•
Filing: 1940-06-28
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Granted: 1949-12-06
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Expires: 1960-06-28
Abstract
No abstract record available.
Inventors
- 👤 William T Cooke
- 👤 Jr Joe J Caldwell
- 👤 David G Clifford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:35
CPC Classifications
H; H01; H01J; H01J25/00; H01J25/02; H01J25/10; H01J25/12
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1923521A
Cited
US2163589A
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US2167201A
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US2222902A
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US2245627A
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US2227372A
Cited
US2250511A
Cited
US2261154A
Cited
US2263184A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-12-05 | 1953-06-06 | 1953-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-12-05 | 1957-06-06 | 1957-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-12-05 | 1961-06-06 | 1961-12-06 | $7700.00 | Window Closed / Lapsed |