Patent US2452391A successfully refreshed from Google Patents.
US2452391A
Expired / Lapsed
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Heat exchanger
Assignee: NAT RADIATOR Co
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Filing: 1946-01-18
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Granted: 1948-10-26
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Expires: 1966-01-18
Abstract
No abstract record available.
Inventors
- 👤 Frederick J O'sullivan
- 👤 Pont Mary A Du
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:04
CPC Classifications
F; F28; F28D; F28D7/00; F28D7/08; F28D7/082; F28D7/085; F28D7/087; F28D7/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1505576A
Cited
US1623617A
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US1838105A
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US1757136A
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US2022173A
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US2053780A
Cited
US2338040A
Cited
US2432362A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-10-26 | 1952-04-26 | 1952-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-10-26 | 1956-04-26 | 1956-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-10-26 | 1960-04-26 | 1960-10-26 | $7700.00 | Window Closed / Lapsed |