Patent US4633352A successfully refreshed from Google Patents.
US4633352A
Expired / Lapsed
US
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Magnetic field noise shield for a magnetic head
Assignee: YE Data Inc
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Filing: 1985-03-29
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Granted: 1986-12-30
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Expires: 2005-03-29
Abstract
Abstract A magnetic head which includes a head piece, a gimbal movably supporting the headpiece and a layer of low electrical resistance metal formed on the surface of the gimbal so as to shield the head piece from relatively high frequency magnetic field noise.
Inventors
- 👤 Toshiaki Mizoguchi
- 👤 Shinichiro Wadaya
- 👤 Kunihiro Hashimoto
- 👤 Shinichi Takase
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:58
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/4806; G11B5/4826; G11B5/10; G11B5/11
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
105 words
A magnetic head, comprising: a head piece; and a gimbal spring having a first portion, and a second portion elastically movably supported by and connected to said first portion, said head piece being mounted on said second portion so that said head piece is movably directly supported on said second portion, said second portion of said gimbal being formed of a layer of low electrical resistance metal and a material having a resistivity substantially greater than that of said layer of metal, said layer being oriented and positioned sufficiently close to said head piece so as to shield said head piece from magnetic field noise.
Claim 2
Dependent Claim
105 words
A magnetic head, comprising: a head piece; and a gimbal spring having a first portion, and a second portion elastically movably supported by and connected to said first portion, said head piece being mounted on said second portion so that said head piece is movably directly supported on said second portion, said second portion of said gimbal being formed of a layer of low electrical resistance metal and a material having a resistivity substantially greater than that of said layer of metal, said layer being oriented and positioned sufficiently close to said head piece so as to shield said head piece from magnetic field noise.
Claim 3
Dependent Claim
18 words
A magnetic head as in claim 1, wherein a portion of said layer directly opposes said head piece.
Claim 4
Dependent Claim
25 words
A magnetic head as in claim 1, wherein said second portion is movably supported by said first portion on opposite sides of said second portion.
Claim 5
Dependent Claim
40 words
A magnetic head as in claim 1, wherein said gimbal is formed from an elastic plate having an upper surface and a lower surface opposite said upper surface, said layer being formed on both said upper and said lower surfaces.
Claim 6
Dependent Claim
119 words
A magnetic head as in claim 4, wherein said plate has an outer fixed portion having a first outer periphery, a first hinge portion and a swingable inner portion having a center and a second outer periphery, surrounded by said outer portion and connected to said outer portion by said first hinge portion, said inner portion being spaced from said outer portion by a first narrow slit extending all about said second periphery except at said first hinge portion, said head piece being fixed to said inner portion, the dimension of said first narrow slit being small in relation to the dimensions of said inner and outer portions measured in directions from said center toward said first outer periphery.
Claim 7
Dependent Claim
104 words
a magnetic head as in claim 5, wherein said inner portion includes an internal portion having a third outer periphery, an external portion surrounding said internal portion, and a second hinge portion hingedly connecting said internal portion to said external portion, said internal and external portions being spaced from each other by a second narrow slit all about said third periphery of said internal portion except at said second hinge portion, said head piece being fixed to said internal portion, the dimension of said second narrow slit being small in relation to the dimensions of said internal and external portions measured in said directions.
Claim 8
Dependent Claim
19 words
A magnetic head as in claim 4, wherein said layer completely covers said upper surface and said lower surface.
Claim 9
Dependent Claim
41 words
A magnetic head as in claim 1, wherein said first and second portions are formed from an integral plate, having upper and lower surfaces, said layer completely covering at least one of said upper surface and lower surface of said plate.
Claim 10
Dependent Claim
39 words
A magnetic head as in claim 1, wherein said second portion comprises a flat plate-shaped member having an upper surface and a lower surface, said layer completely covering at least one of said upper surface and said lower surface.
Claim 11
Dependent Claim
21 words
A magnetic head as in claim 1, wherein said low electrical resistance metal consists substantially of one of copper and aluminum.
Claim 12
Dependent Claim
13 words
A magnetic head as in claim 1, wherein said gimbal spring is planar.
Claim 13
Dependent Claim
32 words
A magnetic head as in claim 1, wherein said head piece is mounted on said second portion so as to allow said head piece to flex relative to a gimbal support mechanism.
Claim 14
Dependent Claim
27 words
A magnetic head as in claim 1, wherein said layer is formed on and is coextensive with an outer surface of said second portion on said material.
Claim 15
Dependent Claim
45 words
A magnetic head as in claim 1, wherein a portin of said gimbal is formed from an elastic plate having an upper surface and a lower surface opposite said upper surface, said layer being formed on at least one of said upper and lower surfaces.
Claim 16
Dependent Claim
129 words
A magnetic head, comprising a head piece, and a gimbal spring having a first portion, a second portion elastically supported by and connected to said first portion, said head piece being mounted on said second portion so that said head piece is movably directly supported on said second portion, said second portion of said gimbal being formed of a layer of low electrical resistance metal and a metal material having a resistivity substantially greater than that of said layer of metal, said layer and said metal material being oriented and positioned sufficiently close to said head piece, so as to shield said head piece respectively from first and second ranges of frequency of magnetic field noise, the second range of frequencies being higher than the first range of frequencies.
Claim 17
Dependent Claim
129 words
A magnetic head, comprising a head piece, and a gimbal spring having a first portion, a second portion elastically supported by and connected to said first portion, said head piece being mounted on said second portion so that said head piece is movably directly supported on said second portion, said second portion of said gimbal being formed of a layer of low electrical resistance metal and a metal material having a resistivity substantially greater than that of said layer of metal, said layer and said metal material being oriented and positioned sufficiently close to said head piece, so as to shield said head piece respectively from first and second ranges of frequency of magnetic field noise, the second range of frequencies being higher than the first range of frequencies.
Claim 18
Dependent Claim
14 words
A magnetic head as in claim 15, wherein said metal material consists of steel.
Claim 19
Dependent Claim
14 words
A magnetic head as in claim 15, wherein said metal material comprises phosphor bronze.
Claim 20
Dependent Claim
13 words
A magnetic head as in claim 15, wherein said gimbal spring is planar.
Claim 21
Dependent Claim
32 words
A magnetic head as in claim 15, wherein said head piece is mounted on said second portion so as to allow said head piece to flex relative to a gimbal support mechanism.
Claim 22
Dependent Claim
27 words
A magnetic head as in claim 15, wherein said layer is formed on and is coextensive with an outer surface of said second portion on said material.
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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) | 1989-12-29 | 1990-06-30 | 1990-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-29 | 1994-06-30 | 1994-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-29 | 1998-06-30 | 1998-12-30 | $7700.00 | Window Closed / Lapsed |