Patent US2989476A successfully refreshed from Google Patents.
US2989476A
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Ferrite with constricted magnetic hysteresis loop
Assignee: Steatit Magnesia AG
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Filing: 1956-11-05
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Granted: 1961-06-20
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Expires: 1976-11-05
Abstract
No abstract record available.
Inventors
- 👤 Eckert Oskar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:56
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/26; C04B35/2608; C04B35/2625; C04B35/265
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
134 words
A COBALT-MODIFIED FERRITE WITH A CONSTRICTED MAGNETIC HYSTERESIS LOOP, SAID FERRITE BEING OF THE CLASS CONSISTING OF NICKEL-COPPER-IRON AND NICKEL-MAGNESIUM-IRON SYSTEMS CONTAINING 0.1 TO 5% BY WEIGHT OF COBALT OXIDE, THE IRON OXIDE CONTENT OF SAID COMPOSITION BEING AT LEAST 50 MOL PERCENT EXPRESSED IN METAL OXIDES, SAID FERRITE EXCLUSIVE OF THE COBALT OXIDE CONTENT CONTAINING ABOUT 72.5 TO 90% BY WEIGHT OF FERRIC OXIDE, ABOUT 10 TO 27.5% BY WEIGHT OF NIO AND THE REMAINDER CONSISTING ESSENTIALLY OF A METAL OXIDE SELECTED FROM THE GROUP CONSISTING OF UP TO 25% BY WEIGHT OF CUO AND UP TO 22.5% BY WEIGHT OF MGO, SAID FERRITE BEING FORMED BY SINTERING AT ABOUT 1180*C. TO ABOUT 1400*C. AND COOLING THE SINTERED FERRITE FROM 700*C. DOWN TO ROOM TEMPERATURE OVER A PERIOD OF AT LEAST TWELVE HOURS.
Claim 2
Dependent Claim
134 words
A COBALT-MODIFIED FERRITE WITH A CONSTRICTED MAGNETIC HYSTERESIS LOOP, SAID FERRITE BEING OF THE CLASS CONSISTING OF NICKEL-COPPER-IRON AND NICKEL-MAGNESIUM-IRON SYSTEMS CONTAINING 0.1 TO 5% BY WEIGHT OF COBALT OXIDE, THE IRON OXIDE CONTENT OF SAID COMPOSITION BEING AT LEAST 50 MOL PERCENT EXPRESSED IN METAL OXIDES, SAID FERRITE EXCLUSIVE OF THE COBALT OXIDE CONTENT CONTAINING ABOUT 72.5 TO 90% BY WEIGHT OF FERRIC OXIDE, ABOUT 10 TO 27.5% BY WEIGHT OF NIO AND THE REMAINDER CONSISTING ESSENTIALLY OF A METAL OXIDE SELECTED FROM THE GROUP CONSISTING OF UP TO 25% BY WEIGHT OF CUO AND UP TO 22.5% BY WEIGHT OF MGO, SAID FERRITE BEING FORMED BY SINTERING AT ABOUT 1180*C. TO ABOUT 1400*C. AND COOLING THE SINTERED FERRITE FROM 700*C. DOWN TO ROOM TEMPERATURE OVER A PERIOD OF AT LEAST TWELVE HOURS.
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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) | 1964-06-19 | 1964-12-19 | 1965-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-06-19 | 1968-12-19 | 1969-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-06-19 | 1972-12-19 | 1973-06-20 | $7700.00 | Window Closed / Lapsed |