Patent US2461253A successfully refreshed from Google Patents.
Patent US4896235A successfully refreshed from Google Patents.
US4896235A
Expired / Lapsed
US
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Magnetic transducer head utilizing magnetoresistance effect
Assignee: Sony Corp
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Filing: 1989-01-17
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Granted: 1990-01-23
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Expires: 2009-01-17
Abstract
Abstract A MR magnetic head with a sensing element which comprises a plurality of superposed magnetic layers which have a magnetoresistance effect in at least one and a nonmagnetic intermediate layer sandwiched between the magnetic layers, and a sensing current is fed so as to flow in the sensing element in the same direction as a signal magnetic field which is applied to the element. Each of the magnetic layers is formed so as to have an easy axis of magnetization which is substantially perpendicular to the signal magnetic field or to have an isotropic magnetic characteristic in the magnetic film plane, which eliminates Barkhausen noise.
Inventors
- 👤 Hiroshi Takino
- 👤 Shigeyoshi Imakoshi, deceased
- 👤 Nobuhiro Terada
- 👤 Norio Saito
- 👤 Hideo Suyama
- 👤 Kenichiro Tsunewaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:47
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/33; G11B5/39; G11B5/3903; G11B5/3906; G11B5/3916; G11B5/3919; G11B5/3922; G11B5/3925; G11B5/3929; G11B5/3935; G11B5/3941; G11B5/3945; G11B5/3948; G11B5/3951; G11B5/3954; G11B5/3958; G11B5/3961; G11B5/3964; G11B5/398; G11B5/399; G11B5/31; G11B5/3109; G11B5/313; G11B5/3143; G11B5/3146; G11B5/3153; G11B5/3156
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
229 words
A magnetic transducer head utilizing magnetoresistance effect comprising; first and second sensing elements arranged parallel to each other and each subject to a common signal magnetic field, each of said first and second sensing elements being composed of first and second soft magnetic layers which are superimposed and a nonmagnetic layer mounted between said first and second soft magnetic layers and forming a track width (TW), at least one of said first and second soft magnetic layers having a magnetoresistance effect and said first and second soft magnetic layers magnetostatically coupled through said nonmagnetic layer, a pair of electrodes connected to each of said first and second sensing elements at first and second end portions of each of said first and second sensing elements and said first and second sensing elements connected in series, a sense current flows through said first and second sensing elements in opposite directions, said first and second sensing elements receiving a signal magnetic field which is parallel to said sense current, and said first and second soft magnetic layers having an easy axis of magnetization which is substantially perpendicular to said sense current, at least one slit formed in said first and second sensing elements in a direction perpendicular to said track width and a coupling layer 29 extending between said first and second sense elements in a direction parallel to said track width.
Claim 2
Dependent Claim
229 words
A magnetic transducer head utilizing magnetoresistance effect comprising; first and second sensing elements arranged parallel to each other and each subject to a common signal magnetic field, each of said first and second sensing elements being composed of first and second soft magnetic layers which are superimposed and a nonmagnetic layer mounted between said first and second soft magnetic layers and forming a track width (TW), at least one of said first and second soft magnetic layers having a magnetoresistance effect and said first and second soft magnetic layers magnetostatically coupled through said nonmagnetic layer, a pair of electrodes connected to each of said first and second sensing elements at first and second end portions of each of said first and second sensing elements and said first and second sensing elements connected in series, a sense current flows through said first and second sensing elements in opposite directions, said first and second sensing elements receiving a signal magnetic field which is parallel to said sense current, and said first and second soft magnetic layers having an easy axis of magnetization which is substantially perpendicular to said sense current, at least one slit formed in said first and second sensing elements in a direction perpendicular to said track width and a coupling layer 29 extending between said first and second sense elements in a direction parallel to said track width.
Claim 3
Dependent Claim
190 words
A magnetic transducer head utilizing magnetoresistance effect comprising; a plurality of sensing elements arranged parallel to each other and receiving a common signal magnetic field across a track width (TW), each of said plurality of sensing elements each comprising first and second superimposed soft magnetic layers and a nonmagnetic layer between said first and second soft magnetic layers, at least one of said soft magnetic layers having a magnetoresistance effect and said first and second soft magnetic layers magnetostatically coupled to each other through said nonmagnetic layer, electrodes connected to each of said plurality of sensing elements which are connected in series so that a sense current flows through said sensing elements in opposite directions, said plurality of sensing elements receiving said signal magnetic field which is parallel to said sense currents, and said first and second soft magnetic layers having an easy axis of magnetization which is substantially perpendicular to said sense currents, a slit formed in said plurality sensing elements in a direction perpendicular to said track width and a coupling layer (29) extending between said plurality of sensing elements in a direction parallel to said track width.
Claim 4
Dependent Claim
190 words
A magnetic transducer head utilizing magnetoresistance effect comprising; a plurality of sensing elements arranged parallel to each other and receiving a common signal magnetic field across a track width (TW), each of said plurality of sensing elements each comprising first and second superimposed soft magnetic layers and a nonmagnetic layer between said first and second soft magnetic layers, at least one of said soft magnetic layers having a magnetoresistance effect and said first and second soft magnetic layers magnetostatically coupled to each other through said nonmagnetic layer, electrodes connected to each of said plurality of sensing elements which are connected in series so that a sense current flows through said sensing elements in opposite directions, said plurality of sensing elements receiving said signal magnetic field which is parallel to said sense currents, and said first and second soft magnetic layers having an easy axis of magnetization which is substantially perpendicular to said sense currents, a slit formed in said plurality sensing elements in a direction perpendicular to said track width and a coupling layer (29) extending between said plurality of sensing elements in a direction parallel to said track width.
Claim 5
Dependent Claim
25 words
A magnetic transducer head utilizing magnetoresistance effect according to claim 1 or 2, wherein said nonmagnetic layer has a thickness between 5 and 10,000 Å.
Claim 6
Dependent Claim
29 words
A magnetic transducer head utilizing magnetoresistance effect according to claim 1 or 2, wherein each of said electrodes is connected to said first and second soft magnetic layers respectively.
Claim 7
Dependent Claim
29 words
A magnetic transducer head utilizing magnetoresistance effect according to claim 1 or 2, wherein said first and second soft magnetic layers are electrically connected together through said nonmagnetic layer.
Claim 8
Dependent Claim
38 words
A magnetic transducer head utilizing magnetoresistance effect according to claim 1 or 2, wherein said first soft magnetic layer has a relatively large magnetoresistance effect and said second soft magnetic layer has no or a small magnetoresistance effect.
Claim 9
Dependent Claim
64 words
A magnetic transducer head utilizing magnetoresistance effect according to claim 1 or 2, wherein said first soft magnetic layer has a relatively large magnetoresistance effect, said second soft magnetic layer has no or a small magnetoresistance effect, said first and second soft magnetic layers are electrically insulated by said nonmagnetic layer, and said pair of electrodes are connected to said first soft magnetic layer.
Claim 10
Dependent Claim
32 words
A magnetic transducer head utilizing magnetoresistance effect according to claim 1 or 2, further comprising means for applying a bias magnetic field to each of said sensing elements along said one direction.
Claim 11
Dependent Claim
43 words
A magnetic transducer head utilizing magnetoresistance effect according to claim 8, wherein said means for applying a bias magnetic field is a conductor provided adjacent to each of said sensing elements to cause a bias current to flow parallel to said sense currents.
Claim 12
Dependent Claim
31 words
A magnetic transducer head utilizing magnetoresistance effect according to claim 1 or 2, wherein said sensing elements are arranged to face at one ends thereof to a travelling magnetic recording medium.
Claim 13
Dependent Claim
56 words
A magnetic transducer head utilizing magnetoresistance effect according to claim 1 or 2, further comprising a magnetic substrate, a first magnetic yoke which makes a gap with said magnetic substrate, a second magnetic yoke magnetically connected to said magnetic substrate and each of said sensing element is provided to magnetically connect said first and second yokes.
Claim 14
Dependent Claim
30 words
A magnetic transducer head utilizing magnetoresistance effect according to claim 1 wherein each of said sensing elements is arranged to have one end face a adjacent travelling magnetic recording medium.
Claim 15
Dependent Claim
54 words
A magnetic transducer head utilizing magnetoresistance effect according to claim 1, further comprising a magnetic substrate, a first magnetic yoke which makes a gap with said magnetic substrate, a second magnetic yoke magnetically connected to said magnetic substrate and each of said sensing elements is provided to magnetically connect said first and second yokes.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-01-22 | 1993-07-24 | 1994-01-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-22 | 1997-07-24 | 1998-01-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-22 | 2001-07-24 | 2002-01-23 | $7700.00 | Window Closed / Lapsed |