Patent US2999305A successfully refreshed from Google Patents.
US2999305A
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US
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Spiral heat exchanger
Assignee: Reynolds Metals Co
•
Filing: 1955-12-27
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Granted: 1961-09-12
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Expires: 1975-12-27
Abstract
No abstract record available.
Inventors
- 👤 William G Reynolds
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:39
CPC Classifications
B; B21; B21D; B21D53/00; B21D53/02; B21D53/04; B21D53/045; F; F28; F28D; F28D9/00; F28D9/04; F28F; F28F3/00; F28F3/02; F28F3/025; F28F3/027; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/4935; Y10T29/49366; Y10T29/49369; Y10T29/49371; Y10T29/49805
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1775819A
Cited
US1712085A
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US2088391A
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US2289685A
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US2312451A
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US2375334A
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US2657018A
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US2662273A
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US2759247A
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US2845695A
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US2766514A
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US2779173A
Cited
US2859509A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-09-11 | 1965-03-13 | 1965-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-09-11 | 1969-03-13 | 1969-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-09-11 | 1973-03-13 | 1973-09-12 | $7700.00 | Window Closed / Lapsed |