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US2184741A
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High frequency smelting furnace
Assignee: Kohle und Eisenforschung GmbH
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Filing: 1938-11-17
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Granted: 1939-12-26
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Expires: 1958-11-17
Abstract
No abstract record available.
Inventors
- 👤 Hartmann Fritz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:17
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/02; H05B6/22; H05B6/24; H05B6/28
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1942-12-25 | 1943-06-26 | 1943-12-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-12-25 | 1947-06-26 | 1947-12-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-12-25 | 1951-06-26 | 1951-12-26 | $7700.00 | Window Closed / Lapsed |