Patent US2992474A successfully refreshed from Google Patents.
US2992474A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic tape recorder heads
Assignee: Individual
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Filing: 1958-11-17
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Granted: 1961-07-18
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Expires: 1978-11-17
Abstract
No abstract record available.
Inventors
- 👤 Adams Edmond
- 👤 William M Hubbard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:03
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; G; G11; G11B; G11B5/00; G11B5/127; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9265; Y10S428/928; Y10T; Y10T428/00; Y10T428/12; Y10T428/12229; Y10T428/12236; Y10T428/12243; Y10T428/12333; Y10T428/12493; Y10T428/12535; Y10T428/12556; Y10T428/12569; Y10T428/12771; Y10T428/12861; Y10T428/12951
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
70 words
A CORE OF MAGNETIC MATERIAL FORMED TO DEFINE A SUBSTANTIALLY CLOSED MAGNETIC LOOP INTERRUPTED BY A NONMAGNETIC SPACER, SAID CORE BEING COMPRISED OF A SINCERED TERNARY ALLOY HAVING AN ALUMINUN CONTENT FROM 4% TO 6.5%, A SILICON CONTENT FROM 8% TO 11% WITH THE REMAINDER ESSENTIALLY IRON, SAID ALLOY BEING CHARACTERIZED BY A PHYSICAL HARDNESS OF 70 TO 7K ROCKWELL A AND AN ELECTRICAL RESISTIVITY OF 75 TO 85 MICRO-OHM-CENTIMETERS.
Claim 2
Dependent Claim
70 words
A CORE OF MAGNETIC MATERIAL FORMED TO DEFINE A SUBSTANTIALLY CLOSED MAGNETIC LOOP INTERRUPTED BY A NONMAGNETIC SPACER, SAID CORE BEING COMPRISED OF A SINCERED TERNARY ALLOY HAVING AN ALUMINUN CONTENT FROM 4% TO 6.5%, A SILICON CONTENT FROM 8% TO 11% WITH THE REMAINDER ESSENTIALLY IRON, SAID ALLOY BEING CHARACTERIZED BY A PHYSICAL HARDNESS OF 70 TO 7K ROCKWELL A AND AN ELECTRICAL RESISTIVITY OF 75 TO 85 MICRO-OHM-CENTIMETERS.
References Cited (Backward Citations)
US2864734A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-07-17 | 1965-01-16 | 1965-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-07-17 | 1969-01-16 | 1969-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-07-17 | 1973-01-16 | 1973-07-18 | $7700.00 | Window Closed / Lapsed |