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US2520535A
Expired / Lapsed
US
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Control system for air-conditioning apparatus
Assignee: UNITED STATES AIR CONDITIONING Corp
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Filing: 1948-06-19
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Granted: 1950-08-29
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Expires: 1968-06-19
Abstract
No abstract record available.
Inventors
- 👤 Ewald Warren
- 👤 Charles E Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:31
CPC Classifications
F; F24; F24F; F24F11/00; F24F11/30; F24F11/88
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2242728A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-08-28 | 1954-02-27 | 1954-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-08-28 | 1958-02-27 | 1958-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-08-28 | 1962-02-27 | 1962-08-29 | $7700.00 | Window Closed / Lapsed |