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US3390385A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic drum recording apparatus with replaceable sleeve

Assignee: Unisys Corp
•
Filing: 1966-02-01
•
Granted: 1968-06-25
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Expires: 1986-02-01
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Abstract

No abstract record available.

Inventors

  • 👤 Gregory J Ehalt

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 03:25
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/74; G11B5/76

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 115 words
IN A MAGNETIC RECORDING-REPRODUCING APPARATUS WHERE MAGNETIC TRANSDUCER MEMBERS RECORD AND REPRODUCE FROM A RECORD SURFACE COMPRISING: (A) A ROTATABLE MANDREL MEANS; (B) A DRIVING MEANS CONNECTED TO SAID MANDREL MEANS FOR EFFECTING ROTATION THEREOF; (C) A SEPARATE RECORDING SLEEVE MEANS HAVING AN INNER SURFACE AND CONTAINING ON A PERIPHERAL SURFACE THEREOF A MAGNETIZABLE COATING, SAID SLEEVE MEANS BEING ADAPTED TO BE RECEIVED BY A SURFACE OF SAID ROTATABLE MANDREL MEANS; AND (D) SAID ROTATABLE MANDREL MEANS SUPPORTING PRESSURE MEANS FOR APPLYING A POSITIVE PRESSURE DIRECTED OUTWARDLY FOR MAINTAINING SAID SLEEVE MEANS AND SAID MANDREL MEANS IN A NON-RELATIVE MOTIN RELATIONSHIP WITH RESPECT TO EACH OTHER WHEN SAID MANDREL MEANS IS IN A ROTATING CONDITION.
Claim 2
Dependent Claim 115 words
IN A MAGNETIC RECORDING-REPRODUCING APPARATUS WHERE MAGNETIC TRANSDUCER MEMBERS RECORD AND REPRODUCE FROM A RECORD SURFACE COMPRISING: (A) A ROTATABLE MANDREL MEANS; (B) A DRIVING MEANS CONNECTED TO SAID MANDREL MEANS FOR EFFECTING ROTATION THEREOF; (C) A SEPARATE RECORDING SLEEVE MEANS HAVING AN INNER SURFACE AND CONTAINING ON A PERIPHERAL SURFACE THEREOF A MAGNETIZABLE COATING, SAID SLEEVE MEANS BEING ADAPTED TO BE RECEIVED BY A SURFACE OF SAID ROTATABLE MANDREL MEANS; AND (D) SAID ROTATABLE MANDREL MEANS SUPPORTING PRESSURE MEANS FOR APPLYING A POSITIVE PRESSURE DIRECTED OUTWARDLY FOR MAINTAINING SAID SLEEVE MEANS AND SAID MANDREL MEANS IN A NON-RELATIVE MOTIN RELATIONSHIP WITH RESPECT TO EACH OTHER WHEN SAID MANDREL MEANS IS IN A ROTATING CONDITION.

References Cited (Backward Citations)

US793140A Cited
US2668718A Cited
US2753181A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1971-06-25 1971-12-25 1972-06-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1975-06-25 1975-12-25 1976-06-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1979-06-25 1979-12-25 1980-06-25 $7700.00 Window Closed / Lapsed

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