Patent US4071868A successfully refreshed from Google Patents.
US4071868A
Expired / Lapsed
US
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Narrow track MR head with side shields
Assignee: Panasonic Holdings Corp
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Filing: 1975-12-16
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Granted: 1978-01-31
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Expires: 1995-12-16
Abstract
Abstract A magnetic head consists of a magnetic flux converging core having a magnetic gap and a magnetoresistive effect element which forms a magnetic circuit and which is arranged in the same plane as the magnetic gap. The direction of thickness of the magnetic circuit is aligned with the direction of width of a track of a record medium, and shielding plates of ferromagnetic material are arranged on both sides of the plane.
Inventors
- 👤 Nobuyuki Kaminaka
- 👤 Kenji Kanai
- 👤 Norimoto Nouchi
- 👤 Noboru Nomura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:59
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/33; G11B5/39; G11B5/3903; G11B5/10; G11B5/11
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
78 words
A magnetic head for use with a record medium having at least one track therein, comprising: a magnetic circuit element including, a ferromagnetic material section having a magnetic gap, and a magnetoresistive effect element section situated in the same plane as said ferromagnetic material section, and ferromagnetic shielding plates positioned on both sides of said magnetic circuit element, the thickness direction of said magnetic circuit element coinciding with the width direction of a track in said record medium.
Claim 2
Dependent Claim
78 words
A magnetic head for use with a record medium having at least one track therein, comprising: a magnetic circuit element including, a ferromagnetic material section having a magnetic gap, and a magnetoresistive effect element section situated in the same plane as said ferromagnetic material section, and ferromagnetic shielding plates positioned on both sides of said magnetic circuit element, the thickness direction of said magnetic circuit element coinciding with the width direction of a track in said record medium.
Claim 3
Dependent Claim
27 words
A magnetic head according to claim 1, wherein said shielding plates are substantially parallel to a surface of said magnetic head which abuts against said record medium.
Claim 4
Dependent Claim
27 words
A magnetic head according to claim 1, wherein said shielding plates are each laminated in a direction substantially parallel to the plane of said magnetic circuit element.
Claim 5
Dependent Claim
25 words
A magnetic head according to claim 1, wherein the spacing between said shielding plates increases with the distance from said surface of the record medium.
Claim 6
Dependent Claim
44 words
A magnetic head according to claim 1, wherein said shielding plates are of generally concave shape with the surface thereof which abuts against said record medium being a bottom, and the most deeply recessed portion of said concave shape being aligned with said gap.
Claim 7
Dependent Claim
40 words
A magnetic head according to claim 1 which further includes a non-magnetic substrate having a groove formed in the surface thereof and wherein said shielding plates comprise layers of ferromagnetic material, said ferromagnetic material layers being formed in said groove.
Claim 8
Dependent Claim
46 words
A magnetic head according to claim 6, wherein insulating material layers are disposed on said ferromagnetic material layers in said groove, the surfaces of said insulating material layers and the surface of said substrate being smooth, and saidmagnetic circuit element is disposed on said smooth surfaces.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-01-30 | 1981-08-01 | 1982-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-30 | 1985-08-01 | 1986-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-30 | 1989-08-01 | 1990-01-31 | $7700.00 | Window Closed / Lapsed |