US2668040A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Furnace system
Assignee: Selas Corp of America
•
Filing: 1950-01-26
•
Granted: 1954-02-02
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Expires: 1970-01-26
Abstract
No abstract record available.
Inventors
- 👤 Frederic O Hess
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:13
CPC Classifications
F; F27; F27B; F27B9/00; F27B9/14; F27B9/20; F27B9/24; F27B9/2407; C; C21; C21D; C21D9/00; C21D9/0081; F27B9/02; F27B9/021; F27B9/025
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-02-01 | 1957-08-03 | 1958-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-02-01 | 1961-08-03 | 1962-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-02-01 | 1965-08-03 | 1966-02-02 | $7700.00 | Window Closed / Lapsed |