Patent US2638879A successfully refreshed from Google Patents.
US2638879A
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Apparatus for heat treatment of fluent substances
Assignee: Selas Corp of America
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Filing: 1947-06-30
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Granted: 1953-05-19
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Expires: 1967-06-30
Abstract
No abstract record available.
Inventors
- 👤 Frederic O Hess
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:14
CPC Classifications
B; B01; B01J; B01J19/00; B01J19/24; B01J19/2415; B01J19/2425; B01J2219/00; B01J2219/00049; B01J2219/00051; B01J2219/00054; B01J2219/00056; B01J2219/00058; B01J2219/0006; B01J2219/0015; B01J2219/00155; B01J2219/00157; B01J2219/00159; B01J2219/00162
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2191273A
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US2127815A
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US2046897A
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US2105820A
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US2215079A
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US2215080A
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US2215081A
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US2306818A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-05-18 | 1956-11-17 | 1957-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-18 | 1960-11-17 | 1961-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-18 | 1964-11-17 | 1965-05-19 | $7700.00 | Window Closed / Lapsed |