US2640137A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Temperature control system
Assignee: AT&T Inc
•
Filing: 1950-11-15
•
Granted: 1953-05-26
•
Expires: 1970-11-15
Abstract
No abstract record available.
Inventors
- 👤 Raymond W Ketchledge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:47
CPC Classifications
G; G05; G05D; G05D23/00; G05D23/19; G05D23/27; G05D23/1906
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2324525A
Cited
US1976461A
Cited
US1970103A
Cited
US1985805A
Cited
US2096323A
Cited
US2136682A
Cited
US2404147A
Cited
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 |