US2780415A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat pump operated system for house heating
Assignee: Individual
•
Filing: 1952-02-23
•
Granted: 1957-02-05
•
Expires: 1972-02-23
Abstract
No abstract record available.
Inventors
- 👤 Frazer W Gay
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:24
CPC Classifications
F; F28; F28D; F28D15/00; F28D15/02; F28D15/0233; F24; F24D; F24D11/00; F24D11/02; F24D11/0257; F24T; F24T10/00; F24T10/10; F24T10/30; F24T10/40; F25; F25B; F25B30/00; F25B30/02; F25B30/06; Y; Y02; Y02B; Y02B10/00; Y02B10/40; Y02B10/70; Y02B30/00; Y02B30/13; Y02E; Y02E10/00; Y02E10/10; Y10; Y10T; Y10T137/00; Y10T137/0318; Y10T137/0324
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US475226A
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US2327663A
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US2428876A
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US2484127A
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US2474304A
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US2513373A
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US2693939A
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US2689090A
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US2598397A
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US2584573A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-02-05 | 1960-08-06 | 1961-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-02-05 | 1964-08-06 | 1965-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-02-05 | 1968-08-06 | 1969-02-05 | $7700.00 | Window Closed / Lapsed |