Patent US2981689A successfully refreshed from Google Patents.
US2981689A
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Square loop ferrites
Assignee: Steatite Research Corp
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Filing: 1954-07-12
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Granted: 1961-04-25
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Expires: 1974-07-12
Abstract
No abstract record available.
Inventors
- 👤 Albers-Schoenberg Ernst
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:07
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/26; C04B35/2608; C04B35/2625
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
57 words
A FIRE FERROMAGNETIC FERRITE BODY HAVING A SQUARE HYSTERSIS LOOP CONSISTING ESSENTIALLY OF A MANGANESEMAGNESIUM FERRITE AND CONSISTING ESSENTIALLY OF 8-55 MOL PERCENT OF MAGNESIA, 4-67 MOL PERCENT OF MANGANESE OXIDE AND FROM 25 TO ABOUT 47.5 MOL PERCENT OF FERRIC OXIDE, THE PROPORTIONS OF SAID COMPONENTS BEING WITHIN THE A-B-C-D-E-A OF FIG. 4 OF THE DRAWING.
Claim 2
Dependent Claim
57 words
A FIRE FERROMAGNETIC FERRITE BODY HAVING A SQUARE HYSTERSIS LOOP CONSISTING ESSENTIALLY OF A MANGANESEMAGNESIUM FERRITE AND CONSISTING ESSENTIALLY OF 8-55 MOL PERCENT OF MAGNESIA, 4-67 MOL PERCENT OF MANGANESE OXIDE AND FROM 25 TO ABOUT 47.5 MOL PERCENT OF FERRIC OXIDE, THE PROPORTIONS OF SAID COMPONENTS BEING WITHIN THE A-B-C-D-E-A OF FIG. 4 OF THE DRAWING.
References Cited (Backward Citations)
US2640813A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-04-24 | 1964-10-24 | 1965-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-04-24 | 1968-10-24 | 1969-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-04-24 | 1972-10-24 | 1973-04-25 | $7700.00 | Window Closed / Lapsed |