Patent US2539581A successfully refreshed from Google Patents.
US2539581A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Adjustable spring hold-down for radio tubes
Assignee: Individual
•
Filing: 1946-01-08
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Granted: 1951-01-30
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Expires: 1966-01-08
Abstract
No abstract record available.
Inventors
- 👤 Lawrence T Holden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:50
CPC Classifications
H; H01; H01R; H01R33/00; H01R33/975
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1169497A
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US1429952A
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US1568995A
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US1579832A
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US1616176A
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US1637864A
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US1665095A
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US1985459A
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US1897852A
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US2449646A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-01-29 | 1954-07-31 | 1955-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-29 | 1958-07-31 | 1959-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-29 | 1962-07-31 | 1963-01-30 | $7700.00 | Window Closed / Lapsed |