US4802050A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recording medium
Assignee: Brother Industries Ltd
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Filing: 1987-02-19
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Granted: 1989-01-31
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Expires: 2007-02-19
Abstract
Abstract A magnetic recording medium is disclosed wherein the data tracks are formed of magnetic layers and the non-data tracks are formed of non-magnetic layers. The data tracks and non-data tracks are alternately disposed and the non-data tracks do not effect recording/reproducing/erasing of the data tracks. Another medium is disclosed wherein the magnetic and non-magnetic layers are alternately disposed in the direction of recording/reproducing and the magnetizing transition width is shortened so that the bit length may be shortened. A reproducing apparatus is also disclosed which includes a discriminator for discriminating the magnetizing direction of the magnetic layer on the data tracks on the basis of a detection signal fed from the reproducing head.
Inventors
- 👤 Takeshi Miyabayashi
- 👤 Takemi Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:41
CPC Classifications
B; B82; B82Y; B82Y10/00; G; G11; G11B; G11B5/00; G11B5/012; G11B5/48; G11B5/54; G11B5/55; G11B5/5521; G11B5/74; G11B5/743; G11B5/82
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
68 words
A magnetic recording medium comprising data tracks formed of magnetic layers, and non-data tracks formed of non-magnetic layers, said data tracks and said non-data tracks being disposed alternately and formed on a surface of a disc, and said data tracks having respective widths gradually reduced as the position of the data track comes far from a center of said disc toward an outer circumferential part of said disc.
Claim 2
Dependent Claim
68 words
A magnetic recording medium comprising data tracks formed of magnetic layers, and non-data tracks formed of non-magnetic layers, said data tracks and said non-data tracks being disposed alternately and formed on a surface of a disc, and said data tracks having respective widths gradually reduced as the position of the data track comes far from a center of said disc toward an outer circumferential part of said disc.
Claim 3
Dependent Claim
20 words
A magnetic recording medium according to claim 1, in which said data tracks and said non-data tracks are formed annularly.
Claim 4
Dependent Claim
29 words
The magnetic recording medium in accordance with claim 1 wherein said data tracks formed of magnetic layers and non-magnetic layers are disposed alternatively respectively in the direction of recording/reproducing.
Claim 5
Dependent Claim
118 words
A magnetic recording medium comprising data tracks formed of magnetic layers, and non-data tracks formed of non-magnetic layers, said data tracks and said non-data tracks being disposed alternately and formed annularly, in which the respective widths of said data tracks formed so as to be gradually reduced as the position of the respective data track comes far from the center of said disc toward the outer circumferential part of said disc is selected on the basis of at least one of a linear velocity taken in a radical direction of said disc, a recording electric current, intensity of leakage magnetic field from a head at the surface of said disc, and a rate of change in magnetic flux.
Claim 6
Dependent Claim
118 words
A magnetic recording medium comprising data tracks formed of magnetic layers, and non-data tracks formed of non-magnetic layers, said data tracks and said non-data tracks being disposed alternately and formed annularly, in which the respective widths of said data tracks formed so as to be gradually reduced as the position of the respective data track comes far from the center of said disc toward the outer circumferential part of said disc is selected on the basis of at least one of a linear velocity taken in a radical direction of said disc, a recording electric current, intensity of leakage magnetic field from a head at the surface of said disc, and a rate of change in magnetic flux.
Claim 7
Dependent Claim
29 words
The magnetic recording medium in accordance with claim 4 wherein said data tracks formed of magnetic layers and non-magnetic layers are disposed alternatively respectively in the direction of recording/reproducing.
Claim 8
Dependent Claim
115 words
A magnetic recording system comprising: a magnetic recording medium provided with data tracks composed of magnetic layers and non-magnetic layers, and non-data tracks formed of non-magnetic layers, said data tracks and said non-data tracks being disposed alternatively and formed angularly: a magnetic head for recording information onto said data tracks with one bit of information corresponding to each magnetic layer on the data tracks and for reproducing information; moving means for moving said data tracks of said recording medium relative to a reproducing magnetic head; and discriminating means for discriminating the magnetizing direction of the respective magnetic layer on said data tracks on the basis of a detection signal fed from said reproducing magnetic head.
Claim 9
Dependent Claim
115 words
A magnetic recording system comprising: a magnetic recording medium provided with data tracks composed of magnetic layers and non-magnetic layers, and non-data tracks formed of non-magnetic layers, said data tracks and said non-data tracks being disposed alternatively and formed angularly: a magnetic head for recording information onto said data tracks with one bit of information corresponding to each magnetic layer on the data tracks and for reproducing information; moving means for moving said data tracks of said recording medium relative to a reproducing magnetic head; and discriminating means for discriminating the magnetizing direction of the respective magnetic layer on said data tracks on the basis of a detection signal fed from said reproducing magnetic head.
Claim 10
Dependent Claim
41 words
A magnetic recording medium comprising a large plurality of data tracks radially formed on a surface of a disc and composed of magnetic layers and non-magnetic layers, said magnetic layers and non-magnetic layers being disposed alternately in the direction of recording/reproducing.
Claim 11
Dependent Claim
41 words
A magnetic recording medium comprising a large plurality of data tracks radially formed on a surface of a disc and composed of magnetic layers and non-magnetic layers, said magnetic layers and non-magnetic layers being disposed alternately in the direction of recording/reproducing.
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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) | 1992-01-31 | 1992-08-01 | 1993-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-31 | 1996-08-01 | 1997-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-31 | 2000-08-01 | 2001-01-31 | $7700.00 | Window Closed / Lapsed |