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Dual track magnetic recording method

Assignee: International Business Machines Corp
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Filing: 1982-06-15
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Granted: 1984-11-20
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Expires: 2002-06-15
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Abstract

Abstract A unique dual track recording technique is described in which complementarily magnetically poled regions are simultaneously written in adjacent positions in two parallel tracks. Multi-track recording of magnetic data transitions in oppositely poled matched zones in the separate tracks provides a high flux coupling to a magnetic sensor. The sensor is exposed to the combined flux from both tracks. This also provides a high degree of data redundancy in the event of small physical anomalies in the magnetic medium or writing anomalies in one track or the other. Because a large magnetic field may be coupled, a magnetic sensor may be positioned at some substantial distance above the magnetic medium on which the data is recorded. This overcomes a significant problem in data reading and writing. The present limits of proximity to the magnetic medium of the sensor head or write head have been reached and still higher data density is desired. A high data density recording method is thus described which creates a significant field coupled to a sensor position at a substantial distance above the magnetic storage medium. Reading and writing data at densities upwards of 50,000 flux changes per inch and with channel densities of 4000 per inch may be achieved.

Inventors

  • 👤 Albert W. Vinal

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 11:26
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/02; G11B5/09

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 47 words
A magnetic recording method, comprising steps of: writing a magnetizable magnetic medium with two tracks of magnetic polarities to represent data by simultaneously polarizing said tracks on said medium with laterally adjacent corresponding areas thereof having complementary magnetic poles whose combined track to track properties represent data.
Claim 2
Dependent Claim 47 words
A magnetic recording method, comprising steps of: writing a magnetizable magnetic medium with two tracks of magnetic polarities to represent data by simultaneously polarizing said tracks on said medium with laterally adjacent corresponding areas thereof having complementary magnetic poles whose combined track to track properties represent data.
Claim 3
Dependent Claim 26 words
A method as described in claim 1, wherein: said parallel tracks are written with vertically oriented magnetic polarization vectors relative to the surface of said medium.
Claim 4
Dependent Claim 25 words
A method as described in claim 1, wherein: said parallel tracks are written with horizontally oriented magnetization polarizations relative to the surface of said medium.
Claim 5
Dependent Claim 34 words
A method as described in claim 1 or 2 or 3, wherein: said writing in said two parallel tracks is conducted at a spacing between tracks of approximately 1/2 the width of either track.

References Cited (Backward Citations)

GB792314A Cited
US3281804A Cited
US3287713A Cited
US3665430A Cited
US3962726A Cited
US4303956A Cited
DE3131069A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-11-20 1988-05-21 1988-11-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-11-20 1992-05-21 1992-11-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-11-20 1996-05-21 1996-11-20 $7700.00 Window Closed / Lapsed

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