Patent US2781645A successfully refreshed from Google Patents.
US2781645A
Expired / Lapsed
US
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Heat exchanger
Assignee: Motors Liquidation Co
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Filing: 1952-09-17
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Granted: 1957-02-19
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Expires: 1972-09-17
Abstract
No abstract record available.
Inventors
- 👤 Edward C Simmons
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 08:33
CPC Classifications
F; F25; F25B; F25B39/00; F25B39/02; F25B39/022; F25B39/024; B; B21; B21D; B21D53/00; B21D53/02; B21D53/04; B21D53/045; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/4935; Y10T29/49366; Y10T29/49368; Y10T29/49369
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2143169A
Cited
US2156544A
Cited
US2212481A
Cited
US2451744A
Cited
US2690002A
Cited
US2662273A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-02-19 | 1960-08-20 | 1961-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-02-19 | 1964-08-20 | 1965-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-02-19 | 1968-08-20 | 1969-02-19 | $7700.00 | Window Closed / Lapsed |