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US4644431A
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Magnetic head for a perpendicular magnetic recording system
Assignee: Kao Corp
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Filing: 1984-11-30
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Granted: 1987-02-17
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Expires: 2004-11-30
Abstract
Abstract A magnetic head for recording and reading out of a magnetic recording medium in a perpendicular magnetic recording system is described in which the surface which is close to or in contact with the recording medium are covered with a film of a glasslike carbon material. This film improves the lubrication properties with respect to the adjacent recording medium and serves to prevent abrasion.
Inventors
- 👤 Nobuyuki Kishine
- 👤 Tetsuya Imamura
- 👤 Hideyuki Minami
- 👤 Michihide Yamauchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:13
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/1278; G11B5/187; G11B5/255; G11B5/31; G11B5/3103; G11B5/3106
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
116 words
A magnetic head for use in a perpendicular magnetic recording system which records with a vertical magnetic field component onto a magnetic recording medium with a plane surface and having a receiving circuit axis for easy magnetization which is vertical to the plane, said magnetic head comprising a main pole including soft magnetic thin film having a high magnetic permeability and a high saturated magnetic flux density, and an auxiliary pole which is disposed opposite said main pole so as to be separated via said magnetic recording medium, said magnetic head having at least the portion of said auxiliary pole confronting said magnetic recording medium covered with a non-magnetic film surface comprising a glasslike carbon material.
Claim 2
Dependent Claim
116 words
A magnetic head for use in a perpendicular magnetic recording system which records with a vertical magnetic field component onto a magnetic recording medium with a plane surface and having a receiving circuit axis for easy magnetization which is vertical to the plane, said magnetic head comprising a main pole including soft magnetic thin film having a high magnetic permeability and a high saturated magnetic flux density, and an auxiliary pole which is disposed opposite said main pole so as to be separated via said magnetic recording medium, said magnetic head having at least the portion of said auxiliary pole confronting said magnetic recording medium covered with a non-magnetic film surface comprising a glasslike carbon material.
Claim 3
Dependent Claim
29 words
The magnetic head for a perpendicular magnetic recording system as claimed in claim 1 in which the material of the film surface is an aggregate of glasslike carbon material.
Claim 4
Dependent Claim
36 words
The magnetic head for a perpendicular magnetic recording system as claimed in claim 1 in which the material of the film surface is an aggregate of a composite material consisting mainly of a glasslike carbon material.
Claim 5
Dependent Claim
55 words
The magnetic head for a perpendicular magnetic recording system as claimed in claim 1 in which the film surface is arcuate-shaped on the side adjacent the magnetic recording medium and has a thickness at the center in cross-section parallel to the advancing direction of the magnetic recording medium of from about 3 to 20 μm.
Claim 6
Dependent Claim
41 words
The magnetic head for a perpendicular magnetic recording system as claimed in claim 1 in which the main pole has a surface arranged for contacting said magnetic recording medium also covered with a non-magnetic film surface comprising a glasslike carbon material.
References Cited (Backward Citations)
JPS5334898A
Cited
JPS53132322A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-02-16 | 1990-08-18 | 1991-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-16 | 1994-08-18 | 1995-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-16 | 1998-08-18 | 1999-02-17 | $7700.00 | Window Closed / Lapsed |