US3544884A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Load tap changer apparatus employing parallel circuits comprising vacuum and no-load switches
Assignee: Westinghouse Electric Corp
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Filing: 1968-12-27
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Granted: 1970-12-01
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Expires: 1988-12-27
Abstract
No abstract record available.
Inventors
- 👤 Herbert L Prescott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:43
CPC Classifications
H; H01; H01F; H01F29/00; H01F29/02; H01F29/04
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) | 1973-11-30 | 1974-06-01 | 1974-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-11-30 | 1978-06-01 | 1978-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-11-30 | 1982-06-01 | 1982-12-01 | $7700.00 | Window Closed / Lapsed |