US2528632A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency control system
Assignee: Smith-Meeker Engineering Co
•
Filing: 1947-03-13
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Granted: 1950-11-07
•
Expires: 1967-03-13
Abstract
No abstract record available.
Inventors
- 👤 Frederick B Woodworth
- 👤 Jr Frederick A Lindley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 15:07
CPC Classifications
H; H04; H04K; H04K3/00; H04K3/40; H04K3/45; H04K3/42
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2138042A
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US2209273A
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US2304377A
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US2317547A
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US2369268A
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US2419527A
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US2408791A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-11-06 | 1954-05-08 | 1954-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-11-06 | 1958-05-08 | 1958-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-11-06 | 1962-05-08 | 1962-11-07 | $7700.00 | Window Closed / Lapsed |