Patent US4562503A successfully refreshed from Google Patents.
US4562503A
Expired / Lapsed
US
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Perpendicular magnetic recording head
Assignee: Toshiba Corp
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Filing: 1983-07-20
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Granted: 1985-12-31
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Expires: 2003-07-20
Abstract
Abstract A main magnetic pole member and an auxiliary magnetic pole member of a perpendicular magnetic recording head are disposed such that they are opposed to each other with a recording medium for recording a signal thereon (i.e., a magnetic tape) interposed therebetween. In the central portion of a holder of the main magnetic pole member, a magnetic pole film is embedded such that its upper end edge is exposed on a sliding contact surface of the holder. The magnetic tape is brought into sliding contact with the magnetic pole film. A pair of electrodes are embedded in such a manner as to sandwich an upper end portion of the magnetic pole film within the holder, and at positions spaced by a suitable distance from such upper end portion of the magnetic pole film. The auxiliary magnetic pole member causes the generation of a uniform magnetic flux directed from the auxiliary magnetic pole member toward the magnetic pole film. The magnetic pole film is formed of a magnetic material which has its permeability varied upon application thereto of an electric field. When a voltage is applied to the electrodes in accordance with the signal, an electric field is formed in the magnetic pole film to increase or decrease the permeability thereof, thereby causing an increase or decrease in density of the magnetic flux in the vicinity of the magnetic pole film. Thus, the magnetization of the magnetic tape is inverted or noninverted with the result that perpendicular magnetic recording of the signal is effected.
Inventors
- 👤 Yoshiharu Fujioka
- 👤 Akio Onuki
- 👤 Shushi Takei
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:15
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/1278; G11B5/48; G11B5/52; G11B5/53; G11B5/538
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
106 words
A perpendicular magnetic recording head for recording a signal onto a recording medium comprising: a main magnetic pole means having a magnetic pole film formed of magnetic material and having the main magnetic pole means permeability varied when an electric field is applied thereto, and an electrode means being able to form an electric field in the magnetic pole film corresponding to a signal; and an auxiliary magnetic pole means disposed such that it opposes the main magnetic pole means with the recording medium interposed therebetween and having the capability of forming a magnetic field between the auxiliary magnetic pole means and the magnetic pole film.
Claim 2
Dependent Claim
106 words
A perpendicular magnetic recording head for recording a signal onto a recording medium comprising: a main magnetic pole means having a magnetic pole film formed of magnetic material and having the main magnetic pole means permeability varied when an electric field is applied thereto, and an electrode means being able to form an electric field in the magnetic pole film corresponding to a signal; and an auxiliary magnetic pole means disposed such that it opposes the main magnetic pole means with the recording medium interposed therebetween and having the capability of forming a magnetic field between the auxiliary magnetic pole means and the magnetic pole film.
Claim 3
Dependent Claim
29 words
The perpendicular magnetic recording head according to claim 1, wherein said magnetic pole film is formed of a magnetic material having a piezoelectric effect and inverse effect of magnetostriction.
Claim 4
Dependent Claim
24 words
The perpendicular magnetic recording head according to claim 1, wherein said magnetic pole film is formed of a magnetic material having a magnetoelectric effect.
Claim 5
Dependent Claim
37 words
The perpendicular magnetic recording head according to claim 1, wherein said auxiliary magnetic pole means has an electromagnet having a magnetic member disposed opposing the main pole means, and an exciting coil wound around the magnetic member.
Claim 6
Dependent Claim
26 words
The perpendicular magnetic recording head according to claim 1, wherein said auxiliary magnetic pole means has a permanent magnet disposed opposing the main magnetic pole means.
Claim 7
Dependent Claim
90 words
The perpendicular magnetic recording head according to claim 1, wherein said main magnetic pole means has a rotary member consisting of a circular plate-like non-magnetic material member having a sliding contact surface brought into sliding contact with the recording medium, on its circumferential surface, and a rotating means for allowing said rotary member to rotate about a center thereof; and the magnetic pole film is provided within said rotary member and is exposed on the sliding contact surface thereof so that it may make sliding contact with the recording medium.
Claim 8
Dependent Claim
69 words
The perpendicular magnetic recording head according to claim 6, wherein said electrode means has a pair of electrode embedded within said rotary member in such a manner that said pair of electrodes have the magnetic pole film interposed therebetween and are located at the positions a suitable distance from the magnetic pole film, and a signal source for applying a voltage to the electrodes in accordance with the signal.
Claim 9
Dependent Claim
70 words
The perpendicular magnetic recording head according to claim 1, wherein said main magnetic pole means has a holder formed of non-magnetic material and having a sliding contact surface which can be brought into sliding contact with the recording medium; and said magnetic pole film is provided within the holder and exposed on the sliding contact surface of the holder so that it may make sliding contact with the recording medium.
Claim 10
Dependent Claim
66 words
The perpendicular magnetic recording head according to claim 8, wherein said electrode means has a pair of electrodes embedded within the holder in such a manner that the paired electrodes have the magnetic pole film interposed therebetween and are located at positions a suitable distance from the magnetic pole film, and a signal source for supplying a voltage to the electrodes in accordance with the signal.
Claim 11
Dependent Claim
125 words
A perpendicular magnetic recording head for recording a signal onto a recording medium comprising: a main magnetic pole means having a magnetic pole film consisting of magnetic material and having the main magnetic pole means permeability varied when subjected to distortion, a piezoelectric element capable of causing a distortion in the magnetic pole film when the piezoelectric element is subjected to an electric field, and an electrode means capable of forming an electric field in the piezoelectric element in accordance with the signal; and an auxiliary magnetic pole means disposed such that it opposes the main magnetic pole means with the recording medium interposed therebetween, and having the capability of forming a magnetic field between the auxiliary magnetic pole means and the magnetic pole film.
Claim 12
Dependent Claim
125 words
A perpendicular magnetic recording head for recording a signal onto a recording medium comprising: a main magnetic pole means having a magnetic pole film consisting of magnetic material and having the main magnetic pole means permeability varied when subjected to distortion, a piezoelectric element capable of causing a distortion in the magnetic pole film when the piezoelectric element is subjected to an electric field, and an electrode means capable of forming an electric field in the piezoelectric element in accordance with the signal; and an auxiliary magnetic pole means disposed such that it opposes the main magnetic pole means with the recording medium interposed therebetween, and having the capability of forming a magnetic field between the auxiliary magnetic pole means and the magnetic pole film.
Claim 13
Dependent Claim
71 words
The perpendicular magnetic recording head according to claim 10, wherein said main magnetic pole means has a holder formed of non-magnetic material and having a sliding contact surface which can be brought into sliding contact with the recording medium; and said magnetic pole film is provided within the holder and is exposed on the sliding contact surface of the holder so that it may make sliding contact with the recording medium.
Claim 14
Dependent Claim
88 words
The perpendicular magnetic recording head according to claim 11, wherein the piezoelectric element is embedded within the holder such that it is in contact with the magnetic pole film; and said electrode means has a pair of electrodes embedded within the holder in such manner that one of the pair of electrodes is in contact with the magnetic pole film while the other is in contact with the piezoelectric element, and a signal source for applying a voltage to the pair of electrodes in accordance with the signal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-12-30 | 1989-07-01 | 1989-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-30 | 1993-07-01 | 1993-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-30 | 1997-07-01 | 1997-12-31 | $7700.00 | Window Closed / Lapsed |