Patent US3440704A successfully refreshed from Google Patents.
US3440704A
Expired / Lapsed
US
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Method of constructing a continuous tube finned heat exchanger
Assignee: Sundstrand Heat Transfer Inc
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Filing: 1967-12-26
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Granted: 1969-04-29
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Expires: 1987-12-26
Abstract
No abstract record available.
Inventors
- 👤 William A Collins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 01:51
CPC Classifications
B; B21; B21D; B21D53/00; B21D53/02; B21D53/08; B21D53/085; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/4935; Y10T29/49366; Y10T29/49368; Y10T29/49826; Y10T29/49838; Y10T29/51; Y10T29/5188; Y10T29/53; Y10T29/53113; Y10T29/53122
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2181108A
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US2462511A
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US2458189A
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US2494548A
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US2747258A
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US2941569A
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US3140533A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-04-28 | 1972-10-28 | 1973-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-04-28 | 1976-10-28 | 1977-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-04-28 | 1980-10-28 | 1981-04-29 | $7700.00 | Window Closed / Lapsed |