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A perpendicular magnetic recording and reproducing head apparatus and a magnetic recording system using the same

Assignee: Panasonic Holdings Corp
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Filing: 1981-12-09
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Granted: —
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Expires: 2001-12-09
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Abstract

Abstract A magnetic recording and/or reproducing head comprises a ring-shaped core (41) provided with a gap (43). A pair of coils (421, 422) are wound on the core and connection means (44) are connected to the coils (421, 422) for changing the mode of connection of the coils from between a first condition in which homopolar poles are formed across the gap (43) for recording and a second condition in which heteropoles are formed across the gap (43) for reproduction. The first condition can be achieved with the coils either inversely in parallel or inversely in series. The construction permits recording in a perpendicular direction in a recording medium (11) which can either be a conventional medium or a continuous film of Co-Cr which is perpendicularly anisotropic.

Inventors

  • 👤 Hozumi Hirota
  • 👤 Katsutoshi Iwahara
  • 👤 Tomi Sato

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-06 06:23
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/187; G11B5/245; G11B5/1278

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 102 words
1 . A perpendicular magnetic recording and reproducing head apparatus characterized in that said apparatus is provided with a magnetic core (41) having a gap (43) in the magnetic path in part, at least a pair of coils (421, 422) wound on said magnetic core (41), and a connecting means (44) capable of changing said coils into a connecting condition for generating homopolar magnetic charges in a pair of magnetic poles opposite each other through said gap and into that of generating heteropolar magnetic charges in the same magnetic poles, with respect to a common signal current flowing simultaneously in said coils.
Claim 2
Dependent Claim 102 words
1 . A perpendicular magnetic recording and reproducing head apparatus characterized in that said apparatus is provided with a magnetic core (41) having a gap (43) in the magnetic path in part, at least a pair of coils (421, 422) wound on said magnetic core (41), and a connecting means (44) capable of changing said coils into a connecting condition for generating homopolar magnetic charges in a pair of magnetic poles opposite each other through said gap and into that of generating heteropolar magnetic charges in the same magnetic poles, with respect to a common signal current flowing simultaneously in said coils.
Claim 3
Dependent Claim 26 words
Apparatus according to claim 1, characterised in that the connecting means (44) is arranged to connect said coil inversely in parallel to each other during recording.
Claim 4
Dependent Claim 26 words
Apparatus according to claim 1, characterised in that the connecting means (44) is arranged to connect said coils inversely in series with each other during recording.
Claim 5
Dependent Claim 81 words
A magnetic recording, system which uses a magnetic head having a gap in a magnetic path in member so as to magnetize a medium moving in proximity to said gap, characterised in that a pair of magnetic poles opposite to each other through a gap (43) generate homopolar magnetic charges so that a signal magnetic field is generated in said gap to magnetize said medium (11), said signal magnetic field performing magnetization thicknesswise of said medium, that is, of vertical component.
Claim 6
Dependent Claim 81 words
A magnetic recording, system which uses a magnetic head having a gap in a magnetic path in member so as to magnetize a medium moving in proximity to said gap, characterised in that a pair of magnetic poles opposite to each other through a gap (43) generate homopolar magnetic charges so that a signal magnetic field is generated in said gap to magnetize said medium (11), said signal magnetic field performing magnetization thicknesswise of said medium, that is, of vertical component.
Claim 7
Dependent Claim 39 words
A magnetic recording system according to claim 4, characterised in that said medium (11) is composed of one or more magnetic layers (12) comprising magnetic particles mixed in a binding material, said magnetic layers being coated onto a substrate.
Claim 8
Dependent Claim 28 words
A magnetic recording system according to claim 4, characterised in that said medium (11) comprises a magnetic layer (12) formed on a substrate by means of vapor coating.
Claim 9
Dependent Claim 27 words
A magnetic recording system according to claim 4, characterised in that said medium (11) comprises a magnetic layer (12) formed on said substrate by means of depositing.
Claim 10
Dependent Claim 27 words
A magnetic recording system according to claim 4, characterised in that said medium (11) comprises a magnetic layer (12) formed on said substrate by means of transfer.

References Cited (Backward Citations)

DE1177206B Cited
GB1323093A Cited
DE2034164B2 Cited
US4172171A Cited
JPS5434219A Cited
GB2006509A Cited

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