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US2549468A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic sound recording medium

Assignee: General Electric Co
•
Filing: 1947-11-20
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Granted: 1951-04-17
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Expires: 1967-11-20
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Abstract

No abstract record available.

Inventors

  • 👤 Goodwin H Howe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 20:18
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/64; G11B5/642; Y; Y10; Y10S; Y10S29/00; Y10S29/028

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 107 words
THE METHOD OF PREPARING A STAINLESS STEEL MAGNETIC RECORDING WIRE HAVING GOOD MAGNETIC SOUND RECORDING PROPERTIES, WHICH METHOD COMPRISES MECHANICALLY WORKING A SOFTENED AUSTENITIC STAINLESS STEEL WIRE CONTAINING 17-20 PERCENT CHROMIUM, 7-10 PERCENT NICKEL, AND 0.03 TO 0.25 PERCENT CARBON BY A COLD DRAWING PROCESS TO REDUCE ITS CROSS-SECTIONAL AREA BY AT LEAST ABOUT 94 PERCENT TO A DIAMETER OF ABOUT 4 MILES THEREBY TO PRODUCE AN ELONGATED CRYSTALLINE STRUCTURE IN SAID STEEL AND AGING THE WORK WIRE AT A TEMPERATURE BETWEEN 500* C. AND 700* C. FOR A PERIOD SUFFICIENT TO BRING THE WIRE TO TEMPERATURE AND CAUSE A PRECIPITATION OF CARBIDES PRESENT IN SAID STEEL.
Claim 2
Independent Claim 107 words
THE METHOD OF PREPARING A STAINLESS STEEL MAGNETIC RECORDING WIRE HAVING GOOD MAGNETIC SOUND RECORDING PROPERTIES, WHICH METHOD COMPRISES MECHANICALLY WORKING A SOFTENED AUSTENITIC STAINLESS STEEL WIRE CONTAINING 17-20 PERCENT CHROMIUM, 7-10 PERCENT NICKEL, AND 0.03 TO 0.25 PERCENT CARBON BY A COLD DRAWING PROCESS TO REDUCE ITS CROSS-SECTIONAL AREA BY AT LEAST ABOUT 94 PERCENT TO A DIAMETER OF ABOUT 4 MILES THEREBY TO PRODUCE AN ELONGATED CRYSTALLINE STRUCTURE IN SAID STEEL AND AGING THE WORK WIRE AT A TEMPERATURE BETWEEN 500* C. AND 700* C. FOR A PERIOD SUFFICIENT TO BRING THE WIRE TO TEMPERATURE AND CAUSE A PRECIPITATION OF CARBIDES PRESENT IN SAID STEEL.

References Cited (Backward Citations)

US2080367A Cited
US2044743A Cited
FR875148A Cited
US2489520A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1954-04-16 1954-10-16 1955-04-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1958-04-16 1958-10-16 1959-04-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1962-04-16 1962-10-16 1963-04-17 $7700.00 Window Closed / Lapsed

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