US4783711A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetoresistive sensor having magnetic shields of ferrite
Assignee: Hitachi Ltd
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Filing: 1986-06-27
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Granted: 1988-11-08
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Expires: 2006-06-27
Abstract
Abstract In a magnetoresistive sensor having a magnetoresistive effect element which is held between two sheets of high permeability magnetic ferrite with insulating layers interposed between them, a ferromagnetic metal film is provided adherently to the high permeability magnetic ferrite between the ferrite and the insulating layer, a rise in temperature of the magnetoresistive effect element thereby being held down and a reproduced waveform being made sharp, and thus the characteristics of the element being improved with the life thereof prolonged.
Inventors
- 👤 Masahiro Kitada
- 👤 Hideo Tanabe
- 👤 Noboru Shimizu
- 👤 Hitoshi Nakamura
- 👤 Kazuhiro Momata
- 👤 Shigeyoshi Kato
- 👤 Tooru Takeura
- 👤 Tetsuo Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:12
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; B; B82; B82Y; B82Y25/00; G01; G01R; G01R33/00; G01R33/02; G01R33/06; G01R33/09; G01R33/093; G11B5/33; G11B5/39; G11B5/3903
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
82 words
In a magnetoresistive sensor in which a magnetoresistive effect element having a magnetoresistive film is held between two magnetic shields formed of high permeability magnetic ferrite, with insulating layers interposed between the element and the shields, a magnetoresistive sensor characterized in that, between each of the magnetic shields formed of said high permeability magnetic ferrite and said insulating layer, a ferromagnetic metal film having a higher thermal conductivity than that of said high permeability magnetic ferrite is formed adherently to said ferrite.
Claim 2
Dependent Claim
82 words
In a magnetoresistive sensor in which a magnetoresistive effect element having a magnetoresistive film is held between two magnetic shields formed of high permeability magnetic ferrite, with insulating layers interposed between the element and the shields, a magnetoresistive sensor characterized in that, between each of the magnetic shields formed of said high permeability magnetic ferrite and said insulating layer, a ferromagnetic metal film having a higher thermal conductivity than that of said high permeability magnetic ferrite is formed adherently to said ferrite.
Claim 3
Dependent Claim
36 words
A magnetoresistive sensor according to claim 1, characterized in that the permeability and the saturation flux density of said ferromagnetic metal film are substantially equal to or higher than those of said high permeability magnetic ferrite.
Claim 4
Dependent Claim
32 words
A magnetoresistive sensor according to claim 2, characterized in that the permeability and/or the saturation flux density of said ferromagnetic metal film are higher than those of said high permeability magnetic ferrite.
Claim 5
Dependent Claim
22 words
A magnetoresistive sensor according to claim 2, characterized in that the thickness of said ferromagnetic metal film is 0.1 to 3 μm.
Claim 6
Dependent Claim
22 words
A magnetoresistive sensor according to claim 3, characterized in that the thickness of said ferromagnetic metal film is 0.8 to 3 μm.
Claim 7
Dependent Claim
22 words
A magnetoresistive sensor according to claim 3, characterized in that the thickness of said ferromagnetic metal film is 0.2 to 3 μm.
Claim 8
Dependent Claim
22 words
A magnetoresistive sensor according to claim 1, characterized in that the thickness of said ferromagnetic metal film is 0.1 to 3 μm.
Claim 9
Dependent Claim
19 words
A magnetoresistive sensor according to claim 1, characterized in that said ferromagnetic metal film is a magnetic crystalline material.
Claim 10
Dependent Claim
19 words
A magnetoresistive sensor according to claim 1, characterized in that said ferromagnetic metal film is a magnetic amorphous material.
Claim 11
Dependent Claim
17 words
A magnetoresistive sensor according to claim 9, wherein said magnetic amorphous material is a Co-Mo-Zr amorphous alloy.
Claim 12
Dependent Claim
27 words
A magnetoresistive sensor according to claim 1, wherein said high permeability magnetic ferrite is a material selected from the group consisting of Ni-Zn ferrite and Mn-Zn ferrite.
Claim 13
Dependent Claim
32 words
A magnetoresistive sensor according to claim 1, wherein said ferromagnetic metal film is made of a material selected from the group consisting of Ni-Fe alloy, Fe-Si alloy, Co-Ni alloy and Fe-Si-Al alloy.
Claim 14
Dependent Claim
19 words
A magnetoresistive sensor according to claim 1, wherein said ferromagnetic metal film is made of Ni-19 wt% Fe alloy.
Claim 15
Dependent Claim
18 words
A magnetoresistive sensor according to claim 1, wherein said magnetoresistive film is made of Ni-19 wt% Fe alloy.
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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) | 1991-11-08 | 1992-05-09 | 1992-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-11-08 | 1996-05-09 | 1996-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-11-08 | 2000-05-09 | 2000-11-08 | $7700.00 | Window Closed / Lapsed |