Patent US2731241A successfully refreshed from Google Patents.
US2731241A
Expired / Lapsed
US
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Heat exchange device
Assignee: Individual
•
Filing: 1955-09-07
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Granted: 1956-01-17
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Expires: 1975-09-07
Abstract
No abstract record available.
Inventors
- 👤 Joseph D Christian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:05
CPC Classifications
F; F28; F28F; F28F5/00; F28F5/06; F28D; F28D11/00; F28D11/02; Y; Y10; Y10S; Y10S165/00; Y10S165/135; Y10S165/139; Y10S165/147; Y10S165/148; Y10S165/149
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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Cited
US375165A
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US409409A
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DE438007C
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US1987952A
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US2148205A
Cited
US2231357A
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US2321185A
Cited
US2313705A
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US2434707A
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US2610033A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-01-16 | 1959-07-18 | 1960-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-01-16 | 1963-07-18 | 1964-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-01-16 | 1967-07-18 | 1968-01-17 | $7700.00 | Window Closed / Lapsed |