US2725616A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming air gaps in a transformer
Assignee: LOUIS R DUMAN
•
Filing: 1952-04-11
•
Granted: 1955-12-06
•
Expires: 1972-04-11
Abstract
No abstract record available.
Inventors
- 👤 Epstein Bernard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 02:39
CPC Classifications
H; H01; H01F; H01F38/00; H01F38/08; H01F38/10; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49073
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US1661355A
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US1786422A
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US2385460A
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US2582291A
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US2624106A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-12-05 | 1959-06-06 | 1959-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-12-05 | 1963-06-06 | 1963-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-12-05 | 1967-06-06 | 1967-12-06 | $7700.00 | Window Closed / Lapsed |