Patent US2639686A successfully refreshed from Google Patents.
US2639686A
Expired / Lapsed
US
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Indicator
Assignee: Individual
•
Filing: 1946-03-12
•
Granted: 1953-05-26
•
Expires: 1966-03-12
Abstract
No abstract record available.
Inventors
- 👤 Richard L Duncan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 13:09
CPC Classifications
G; G01; G01K; G01K1/00; G01K1/02; Y; Y10; Y10S; Y10S116/00; Y10S116/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US1513680A
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US1571390A
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US1792319A
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US1878035A
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US2090160A
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US2151976A
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US2112704A
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US2237530A
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US2291610A
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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) | 1956-05-25 | 1956-11-24 | 1957-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-25 | 1960-11-24 | 1961-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-25 | 1964-11-24 | 1965-05-26 | $7700.00 | Window Closed / Lapsed |