US2974401A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Three-phase core for electrical transformers and method of manufacturing the same
Assignee: McGraw Electric Co
•
Filing: 1956-06-01
•
Granted: 1961-03-14
•
Expires: 1976-06-01
Abstract
No abstract record available.
Inventors
- 👤 Martin I Zwelling
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:24
CPC Classifications
H; H01; H01F; H01F41/00; H01F41/02; H01F41/0206; H01F41/0213; H01F27/00; H01F27/24; H01F27/25; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49071
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2344294A
Cited
US2431128A
Cited
US2407391A
Cited
US2404016A
Cited
US2542806A
Cited
US2516164A
Cited
US2543089A
Cited
US2579578A
Cited
US2908880A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-03-13 | 1964-09-12 | 1965-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-03-13 | 1968-09-12 | 1969-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-03-13 | 1972-09-12 | 1973-03-14 | $7700.00 | Window Closed / Lapsed |