US2988508A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Copper containing ferrite cores
Assignee: US Philips Corp
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Filing: 1957-08-09
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Granted: 1961-06-13
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Expires: 1977-08-09
Abstract
No abstract record available.
Inventors
- 👤 Geldermans Pieter
- 👤 Ban Pieter Van Den
- 👤 Holthaus Gerardus Leonardus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:35
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; C; C04; C04B; C04B35/00; C04B35/01; C04B35/26; C04B35/265; H; H01; H01F; H01F41/00; H01F41/02; H01F41/0206; H01F41/0246
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
150 words
A METHOD OF MANUFACTURING AN ANNULAR CORE HAVING AN OUTER DIAMETER OF NOT MORE THAN 4 MMS. AND HAVING A SUBSTANTIALLY SQUARE HYSTERESIS LOOP COMPRISING THE STEPS, FORMING A MIXTURE OF COPPER, MANGANESE AND FERRIC OXIDES IN THE PROPORTIONS OF ABOUT 35 TO 51 MOL PERCENT OF FE2O3, 35 TO 62 MOL PERCENT OF MNO AND 3 TO 14 MOL PERCENT OF CUO, HEATING SAID MIXTURE TO A TEMPERATURE OF ABOUT 600 TO 1000*C. TO FORM A REACTION PRODUCT, FINELY-DIVIDING SAID REACTION PRODUCT, MOLDING THE FINELYDIVIDED REACTION PRODUCT INTO AN ANNULAR BODY OF DESIRED DIMENSIONS, HEATING SAID ANNULAR BODY IN AN ATMOSPHERE CONTAINING AT LEAST AS MUCH OXYGEN AS AIR AT A TEMPERATURE OF ABOUT 1150 TO 1350*C. TO SINTER SAID BODY, AND COOLING SAID BODY IN ABOUT 1 TO 60 MINUTES FROM AT LEAST 700*C. TO AMBIENT TEMPERATURE IN AN ATMOSPHERE CONTAINING ABOUT AS MUCH OXYGEN AS TECHNICAL NITROGEN.
Claim 2
Independent Claim
150 words
A METHOD OF MANUFACTURING AN ANNULAR CORE HAVING AN OUTER DIAMETER OF NOT MORE THAN 4 MMS. AND HAVING A SUBSTANTIALLY SQUARE HYSTERESIS LOOP COMPRISING THE STEPS, FORMING A MIXTURE OF COPPER, MANGANESE AND FERRIC OXIDES IN THE PROPORTIONS OF ABOUT 35 TO 51 MOL PERCENT OF FE2O3, 35 TO 62 MOL PERCENT OF MNO AND 3 TO 14 MOL PERCENT OF CUO, HEATING SAID MIXTURE TO A TEMPERATURE OF ABOUT 600 TO 1000*C. TO FORM A REACTION PRODUCT, FINELY-DIVIDING SAID REACTION PRODUCT, MOLDING THE FINELYDIVIDED REACTION PRODUCT INTO AN ANNULAR BODY OF DESIRED DIMENSIONS, HEATING SAID ANNULAR BODY IN AN ATMOSPHERE CONTAINING AT LEAST AS MUCH OXYGEN AS AIR AT A TEMPERATURE OF ABOUT 1150 TO 1350*C. TO SINTER SAID BODY, AND COOLING SAID BODY IN ABOUT 1 TO 60 MINUTES FROM AT LEAST 700*C. TO AMBIENT TEMPERATURE IN AN ATMOSPHERE CONTAINING ABOUT AS MUCH OXYGEN AS TECHNICAL NITROGEN.
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) | 1964-06-12 | 1964-12-12 | 1965-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-06-12 | 1968-12-12 | 1969-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-06-12 | 1972-12-12 | 1973-06-13 | $7700.00 | Window Closed / Lapsed |