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US2889525A
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Three-phase core for transformers
Assignee: Central Transformer Corp
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Filing: 1954-12-13
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Granted: 1959-06-02
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Expires: 1974-12-13
Abstract
No abstract record available.
Inventors
- 👤 George A Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:06
CPC Classifications
H; H01; H01F; H01F27/00; H01F27/24; H01F27/245; H01F27/2455; H01F41/00; H01F41/02; H01F41/0206; H01F41/0233; H01F41/024
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2467868A
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US2516164A
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US2523072A
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US2579578A
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US2594002A
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US2634321A
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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) | 1962-06-01 | 1962-12-01 | 1963-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-06-01 | 1966-12-01 | 1967-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-06-01 | 1970-12-01 | 1971-06-02 | $7700.00 | Window Closed / Lapsed |