EP0071489A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
A perpendicular magnetic recording and reproducing head
Assignee: Fujitsu Ltd
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Filing: 1982-07-30
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Granted: —
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Expires: 2002-07-30
Abstract
Abstract A perpendicular magnetic recording and reproducing head is disclosed which comprises a spiral coil (16) consisting of at least one electrically conductive thin film, and a main pole (10) consisting of a first thin magnetic film and having an end (11) for recording and reproducing information, the main pole and the spiral coil being electromagnetically coupled to each other. Such a perpendicular magnetic head can be reasonably easily manufactured, can be adapted not only to floppy disks but also to rigid disks, can be suitable for high-frequency operation, and can have an improved recording/reproducing efficiency as compared with conventional magnetic recording and reproducing heads.
Inventors
- 👤 Junzo Toda
- 👤 Masao Hiyane
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 19:23
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/1278
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
54 words
A perpendicular magnetic recording and reproducing head, comprising: a spiral coil consisting of at least one electrically conductive thin film; and a main pole consisting of a first thin magnetic film and having an end for recording information on a medium, said main pole and said spiral coil being electromagnetically coupled to each other.
Claim 2
Dependent Claim
54 words
A perpendicular magnetic recording and reproducing head, comprising: a spiral coil consisting of at least one electrically conductive thin film; and a main pole consisting of a first thin magnetic film and having an end for recording information on a medium, said main pole and said spiral coil being electromagnetically coupled to each other.
Claim 3
Dependent Claim
38 words
A perpendicular magnetic recording and reproducing head as set forth in claim 1, further comprising an insulating film for covering said spiral coil, said main pole extending under said insulating film and under half of said spiral coil.
Claim 4
Dependent Claim
60 words
A perpendicular magnetic recording and reproducing head as set forth in claim 2, further comprising a second thin magnetic film magnetically in contact with the other end of said main pole at the central portion of said spiral coil, said second thin magnetic film extending over said insulating film and at least over the other half of said spiral coil.
Claim 5
Dependent Claim
42 words
A perpendicular magnetic recording and reproducing head as set forth in claim 3, wherein said second thin magnetic film extends over the entire diameter of said spiral coil, said main pole and said second thin magnetic film forming a closed flux structure.
Claim 6
Dependent Claim
32 words
A perpendicular magnetic recording and reproducing head as set forth in claim 3 or 4, wherein said second thin magnetic film has a width larger than the width of said main pole.
Claim 7
Dependent Claim
33 words
A perpendicular magnetic recording and reproducing head as set forth in claim 3, 4 or 5 wherein said second thin magnetic film has a thickness larger than the thickness of said main pole.
Claim 8
Dependent Claim
41 words
A perpendicular magnetic recording and reproducing head as set forth in any preceding claim, wherein said end of said main pole for recording and reproducing information has a width smaller than the width of an opposite end of said main pole.
Claim 9
Dependent Claim
40 words
A perpendicular magnetic recording and reproducing head as set forth in any preceding claim, wherein said end of said main pole for recording and reproducing information has a thickness smaller than the thickness of other portions of said main pole.
Claim 10
Dependent Claim
29 words
A perpendicular magnetic recording and reproducing head as set forth in any preceding claim, wherein said spiral coil comprises one electrically conductive thin film spirally formed in a plane.
Claim 11
Dependent Claim
43 words
A perpendicular magnetic recording and reproducing head as set forth in any one of claims 1 to 8, wherein said spiral coil comprises a number of stacked thin circular films each of said stacked thin circular films being insulated by said insulating film.
Claim 12
Dependent Claim
24 words
A perpendicular magnetic recording and reproducing head as set forth in any preceding claim, further comprising a magneto-resistive element for use in reproducing information.
Claim 13
Dependent Claim
124 words
A perpendicular magnetic recording and reproducing head, comprising: an electrical coil (16) having a plurality of turns made each of substantially planar thin-film electrically conductive material the plane of which is substantially perpendicular to the coil axis, around with the turns extend; and a main pole member (10) which is made of thin-film magnetic material and has an operative end (11) for presentation to a magnetic recording medium (12) when the head is in use and extends, substantially perpendicular to the said coil axis, adjacent to the coil so that electromagnetic coupling between the coil and the main pole member when the head is in use enables recording to be effected in such a medium in accordance with signal currents passed through the coil.
Claim 14
Dependent Claim
124 words
A perpendicular magnetic recording and reproducing head, comprising: an electrical coil (16) having a plurality of turns made each of substantially planar thin-film electrically conductive material the plane of which is substantially perpendicular to the coil axis, around with the turns extend; and a main pole member (10) which is made of thin-film magnetic material and has an operative end (11) for presentation to a magnetic recording medium (12) when the head is in use and extends, substantially perpendicular to the said coil axis, adjacent to the coil so that electromagnetic coupling between the coil and the main pole member when the head is in use enables recording to be effected in such a medium in accordance with signal currents passed through the coil.
References Cited (Backward Citations)
No citation records indexed.
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