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Patent US3368142A successfully refreshed from Google Patents.
US3368142A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-testing variable transformer
Assignee: Northrop Grumman Corp
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Filing: 1965-11-15
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Granted: 1968-02-06
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Expires: 1985-11-15
Abstract
No abstract record available.
Inventors
- 👤 John R Bouchard
- 👤 Packard Henry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 06:20
CPC Classifications
H; H01; H01F; H01F29/00; H01F29/08; H01F29/10
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
75 words
IN A VARIABLE TRANSFORMER, FIRST AND SECOND FERROMAGNETIC POLE PIECES, MEANS CONNECTING SAID POLE PIECES TOGETHER IN SPACED RELATIONSHIP, A THIRD POLE PIECE MOVABLY MOUNTED ADJACENT TO AND CONFRONTING SAID FIRST AND SECOND POLE PIECES, A PRIMARY WINDING LINKING SAID FIRST AND SECOND POLE PIECES, A SECONDARY WINDING LINKING SAID FIRST POLE PIECE, A TERTIARY WINDING LINKING SAID SECOND POLE PIECE, MEANS FOR ENERGIZING SAID PRIMARY WINDING WITH ALTERNATING CURRENT AT A PREDETERMINED FREQUENCY, A
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) | 1971-02-05 | 1971-08-07 | 1972-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-02-05 | 1975-08-07 | 1976-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-02-05 | 1979-08-07 | 1980-02-06 | $7700.00 | Window Closed / Lapsed |