Patent US2638921A successfully refreshed from Google Patents.
US2638921A
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US
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Control system
Assignee: Taylor Instrument Co
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Filing: 1951-01-13
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Granted: 1953-05-19
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Expires: 1971-01-13
Abstract
No abstract record available.
Inventors
- 👤 William I Caldwell
- 👤 Elliot H Woodhull
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 21:30
CPC Classifications
G; G05; G05B; G05B11/00; G05B11/44; G05B11/48; G05B11/50; Y; Y10; Y10T; Y10T137/00; Y10T137/2278; Y10T137/2365; Y10T137/2409; Y10T137/2452; Y10T137/7722; Y10T137/7758; Y10T137/7762; Y10T137/7769
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-05-18 | 1956-11-17 | 1957-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-18 | 1960-11-17 | 1961-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-18 | 1964-11-17 | 1965-05-19 | $7700.00 | Window Closed / Lapsed |