Patent US3655841A successfully refreshed from Google Patents.
US3655841A
Expired / Lapsed
US
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Heat treating sintered manganese-zinc ferrites to improve properties
Assignee: NEC Corp
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Filing: 1970-10-07
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Granted: 1972-04-11
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Expires: 1990-10-07
Abstract
Abstract THE PROPERTIES OF MANGANESE-ZINC FERRITIES ARE IMPROVED BY SUBJECTING PREVIOUSLY SINTERED FERRITIES TO A LOW-TEMPERATURE HEAT TREATMENT AT TEMPERATURES RANGING UP TO ABOUT 400*C. THE ACTUAL TEMPERATURES USED ARE DETERMINED BY THE IRON OXIDE CONTENT OF THE FERRITE.
Inventors
- 👤 Tsuneo Akashi
- 👤 Izuru Sugano
- 👤 Taneaki Okuda
- 👤 Yoshihiro Onodo
- 👤 Toshiro Tsuji
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:57
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/26; C04B35/2658
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-11 | 1975-10-11 | 1976-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-11 | 1979-10-11 | 1980-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-11 | 1983-10-11 | 1984-04-11 | $7700.00 | Window Closed / Lapsed |