Patent US2981521A successfully refreshed from Google Patents.
US2981521A
Expired / Lapsed
US
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Rotary disc regenerator
Assignee: Alstom Power Inc
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Filing: 1957-08-23
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Granted: 1961-04-25
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Expires: 1977-08-23
Abstract
No abstract record available.
Inventors
- 👤 Ted C Evans
- 👤 Charles A Lyle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:57
CPC Classifications
F; F28; F28D; F28D19/00; F28D19/04; F28D19/047; Y; Y02; Y02E; Y02E20/00; Y02E20/34; Y10; Y10S; Y10S165/00; Y10S165/009; Y10S165/013; Y10S165/016; Y10S165/02; Y10S165/021; Y10S165/022
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-04-24 | 1964-10-24 | 1965-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-04-24 | 1968-10-24 | 1969-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-04-24 | 1972-10-24 | 1973-04-25 | $7700.00 | Window Closed / Lapsed |