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US2823691A
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Assignee: Individual
•
Filing: 1955-12-13
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Granted: 1958-02-18
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Expires: 1975-12-13
Abstract
No abstract record available.
Inventors
- 👤 George N Chatham
- 👤 O O Shurtleff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 20:17
CPC Classifications
F; F25; F25B; F25B41/00; F25B41/20; F25B41/26; Y; Y10; Y10T; Y10T137/00; Y10T137/2496; Y10T137/2544; Y10T137/2554; Y10T137/8593; Y10T137/87265; Y10T137/87322; Y10T137/87507; Y10T137/877; Y10T137/87829
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US668202A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-02-17 | 1961-08-19 | 1962-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-02-17 | 1965-08-19 | 1966-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-02-17 | 1969-08-19 | 1970-02-18 | $7700.00 | Window Closed / Lapsed |