US2961221A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat exchange apparatus
Assignee: Babcock and Wilcox Co
•
Filing: 1955-09-07
•
Granted: 1960-11-22
•
Expires: 1975-09-07
Abstract
No abstract record available.
Inventors
- 👤 George F Friese
- 👤 Justin P Winkin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:54
CPC Classifications
F; F22; F22B; F22B3/00; F22B3/02; F22B1/00; F22B1/02; F22B1/021; F22B1/08; Y; Y10; Y10S; Y10S165/00; Y10S165/051; Y10S165/052; Y10S165/053; Y10S165/054; Y10S165/055
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US314559A
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US344586A
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US1326277A
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US1884778A
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US1919029A
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US1883605A
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US2549093A
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US2647495A
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US2640686A
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US2664346A
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US2697420A
Cited
US2655347A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-11-22 | 1964-05-23 | 1964-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-11-22 | 1968-05-23 | 1968-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-11-22 | 1972-05-23 | 1972-11-22 | $7700.00 | Window Closed / Lapsed |