US4578728A
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Magnetic head
Assignee: Panasonic Holdings Corp
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Filing: 1982-11-30
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Granted: 1986-03-25
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Expires: 2002-11-30
Abstract
Abstract The invention provides a magnetic head having a core which includes a thin amorphous alloy film having a composition of Co a M b T c X d , for 70≦a≦95, 0≦b≦20, 3≦c≦20, 0≦d<10, and a+b+c+d=100, where M is at least one metal selected from the group consisting of Fe, Ni, Cr, Mo, W and Mn, T is at least one metal selected from the group consisting of Ti, Zr, Hf, Nb and Ta, and X is at least one material selected from the group consisting of Si, B, C, Al and Ge; and a substrate having excellent resistance to wear and having the thin amorphous alloy film on a major surface thereof, wherein the thin amorphous alloy film is located at least in a portion adjacent a magnetic gap portion of the core which slidably contacts a magnetic recording medium is made of an amorphous alloy.
Inventors
- 👤 Hiroshi Sakakima
- 👤 Mitsuo Satomi
- 👤 Yukihiro Yanagiuchi
- 👤 Harufumi Senno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:29
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/31; G11B5/3103; G11B5/3106
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
128 words
A magnetic head which slideably contacts a magnetic recording medium, said head comprising a core including a substrate having high resistance to wear, a thin amorphous alloy film formed on a major surface of the substrate and forming at least part of a magnetic path, and a magnetic gap provided at a portion of said thin amorphous alloy film which is adjacent to the magnetic recording medium, wherein the thin amorphous alloy film has a composition of Co a M b T c wherein 70≦a≦95, 0≦b≦20, 5≦c≦20 and a+b+c=100, where M is at least one metal selected from the group consisting of Fe, Ni, Cr, Mo, W and Mn, and T is at least one metal selected from the group consisting of Ti, Zr, Hf, Nb and Ta.
Claim 2
Dependent Claim
128 words
A magnetic head which slideably contacts a magnetic recording medium, said head comprising a core including a substrate having high resistance to wear, a thin amorphous alloy film formed on a major surface of the substrate and forming at least part of a magnetic path, and a magnetic gap provided at a portion of said thin amorphous alloy film which is adjacent to the magnetic recording medium, wherein the thin amorphous alloy film has a composition of Co a M b T c wherein 70≦a≦95, 0≦b≦20, 5≦c≦20 and a+b+c=100, where M is at least one metal selected from the group consisting of Fe, Ni, Cr, Mo, W and Mn, and T is at least one metal selected from the group consisting of Ti, Zr, Hf, Nb and Ta.
Claim 3
Dependent Claim
24 words
A magnetic head according to claim 1, wherein a portion of said core which slidably contacts the magnetic recording medium comprises the amorphous alloy.
Claim 4
Dependent Claim
28 words
A magnetic head according to claim 1, wherein the thin amorphous alloy film is located at least in a portion adjacent a magnetic gap of the magnetic core.
Claim 5
Dependent Claim
46 words
A magnetic head according to claim 1, wherein at least one thin ceramic film having excellent resistance to wear and a thickness smaller than a thickness of said thin amorphous alloy film is sandwiched between adjacent ones of a plurality of said thin amorphous alloy films.
Claim 6
Dependent Claim
20 words
A magnetic head according to claim 1, wherein said thin amorphous alloy film is sandwiched between a pair of substrates.
Claim 7
Dependent Claim
12 words
A magnetic head according to claim 1, wherein said substrate comprises ferrite.
Claim 8
Dependent Claim
12 words
A magnetic head according to claim 1, wherein said substrate comprises Sendust.
Claim 9
Dependent Claim
129 words
A magnetic head which slideably contacts a magnetic recording medium said head comprising a core including a substrate having high resistance to wear, a thin amorphous alloy film formed on a major surface of the substrate and forming at least part of a magnetic path, and a magnetic gap provided at a portion of said thin amorphous alloy film which is adjacent to the magnetic recording medium, wherein the thin amorphous alloy film has a composition of Co x Nb y M' z T' u wherein 75≦x≦92, 8≦y≦20, 0.1≦z≦10, 0≦u≦5, and x+y+z+u=100, where M' is at least one material selected from the group consisting of Fe, Ni, Cr, Mo, W and Mn, and T' is at least one material selected from the group consisting of Zr, Ta and Ti.
Claim 10
Dependent Claim
129 words
A magnetic head which slideably contacts a magnetic recording medium said head comprising a core including a substrate having high resistance to wear, a thin amorphous alloy film formed on a major surface of the substrate and forming at least part of a magnetic path, and a magnetic gap provided at a portion of said thin amorphous alloy film which is adjacent to the magnetic recording medium, wherein the thin amorphous alloy film has a composition of Co x Nb y M' z T' u wherein 75≦x≦92, 8≦y≦20, 0.1≦z≦10, 0≦u≦5, and x+y+z+u=100, where M' is at least one material selected from the group consisting of Fe, Ni, Cr, Mo, W and Mn, and T' is at least one material selected from the group consisting of Zr, Ta and Ti.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1989-03-24 | 1989-09-23 | 1990-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-24 | 1993-09-23 | 1994-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-24 | 1997-09-23 | 1998-03-25 | $7700.00 | Window Closed / Lapsed |