Patent US2820615A successfully refreshed from Google Patents.
US2820615A
Expired / Lapsed
US
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Heat exchanger
Assignee: Individual
•
Filing: 1955-01-18
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Granted: 1958-01-21
•
Expires: 1975-01-18
Abstract
No abstract record available.
Inventors
- 👤 Melville F Peters
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:39
CPC Classifications
F; F28; F28F; F28F1/00; F28F1/08; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/4935; Y10T29/49377; Y10T29/49378; Y10T29/4938
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2374609A
Cited
US1164075A
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US1984758A
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US2471317A
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US2446289A
Cited
US2621900A
Cited
US2642897A
Cited
FR1060659A
Cited
US2736533A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-01-20 | 1961-07-22 | 1962-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-20 | 1965-07-22 | 1966-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-20 | 1969-07-22 | 1970-01-21 | $7700.00 | Window Closed / Lapsed |