US2921280A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable coupling transformer device
Assignee: Unisys Corp
•
Filing: 1957-05-13
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Granted: 1960-01-12
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Expires: 1977-05-13
Abstract
No abstract record available.
Inventors
- 👤 Walter J Litwin
- 👤 Frank E Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:55
CPC Classifications
H; H01; H01F; H01F27/00; H01F27/28; H01F29/00; H01F29/08
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) | 1963-01-11 | 1963-07-13 | 1964-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-01-11 | 1967-07-13 | 1968-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-01-11 | 1971-07-13 | 1972-01-12 | $7700.00 | Window Closed / Lapsed |