US4843507A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic head with laminated structure
Assignee: Siemens AG
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Filing: 1987-11-30
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Granted: 1989-06-27
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Expires: 2007-11-30
Abstract
Abstract A magnetic head having layered structure for a recording medium for vertical magnetization contains a conductor body on a non-magnetic substrate for conducting the magnetic flux with two magnet legs, the end pieces of which form a thin main pole and a comparatively thicker auxiliary pole. The two magnetic poles are separated by an insulating gap layer of at least 5 μm. This magnetic head and particularly its gap layer should be relatively simple to produce. Recesses are provided in the substrate to submerge at least the end piece of the auxiliary pole of one magnet leg and an adjoining part of this leg as well as at least part of the gap layer.
Inventors
- 👤 Herbert Schewe
- 👤 Dietrich Stephani
- 👤 Armin Lenhart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:52
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/187; G11B5/23; G11B5/1278
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
185 words
A laminated magnetic head for perpendicularly or vertically magnetizing a recording medium, comprising: a non-magnetic substrate; a magnetic conductor body for carrying magnetic flux, said conductor body having first and second magnetic legs disposed on one side of said substrate; a thin main pole formed on said magnetic conductor body at a first end piece thereof, said first end piece including said first magnetic leg; an auxiliary pole formed on said magnetic conductor body at a second end piece thereof, said second end piece including said second magnetic leg, said first and second end pieces being aligned behind each other along a direction of travel of said head; an insulating gap layer positioned between said first and second end pieces and extending at least 5 μm between said end pieces; a read/write coil winding coil having conductor windings extending between said legs; and a recess in said substrate into which at least said second end piece of said second magnetic leg forming said auxiliary pole, at least one further part of said second leg and at least a part of said gap layer are received.
Claim 2
Dependent Claim
185 words
A laminated magnetic head for perpendicularly or vertically magnetizing a recording medium, comprising: a non-magnetic substrate; a magnetic conductor body for carrying magnetic flux, said conductor body having first and second magnetic legs disposed on one side of said substrate; a thin main pole formed on said magnetic conductor body at a first end piece thereof, said first end piece including said first magnetic leg; an auxiliary pole formed on said magnetic conductor body at a second end piece thereof, said second end piece including said second magnetic leg, said first and second end pieces being aligned behind each other along a direction of travel of said head; an insulating gap layer positioned between said first and second end pieces and extending at least 5 μm between said end pieces; a read/write coil winding coil having conductor windings extending between said legs; and a recess in said substrate into which at least said second end piece of said second magnetic leg forming said auxiliary pole, at least one further part of said second leg and at least a part of said gap layer are received.
Claim 3
Dependent Claim
25 words
A magnetic head as claimed in claim 1, wherein said recess completely receives said second magnet leg, said second end piece and said gap layer.
Claim 4
Dependent Claim
22 words
A magnetic head as claimed in claim 1, wherein said gap layer is formed from glass or Al 2 O 3 .
Claim 5
Dependent Claim
20 words
A magnetic head as claimed in claim 1, wherein said substrate comprises a TiC-AL 2 0 3 mixed ceramic material.
Claim 6
Dependent Claim
39 words
A magnetic head as claimed in claim 1, wherein said auxiliary pole has an area facing the recording medium that is greater in magnitude by at least two orders of magnitude than a corresponding area of said main pole.
Claim 7
Dependent Claim
47 words
A magnetic head as claimed in claim 1, wherein said auxiliary pole has a thickness, measured in the direction of travel of the magnetic head, which is greater than a permissible flux change distance that is determined with respect to a recording code on the recording medium.
Claim 8
Dependent Claim
30 words
A magnetic head as claimed in claim 1, wherein said auxiliary pole has a thickness, measured in the direction of travel of the magnetic head, between 2 and 30 μm.
Claim 9
Dependent Claim
40 words
A magnetic head as claimed in claim 1, wherein said auxiliary pole has a thickness, measured in the direction of travel of the magnetic head, that is at least three times greater than a corresponding thickness of said main pole.
Claim 10
Dependent Claim
38 words
A magnetic head as claimed in claim 8, wherein said auxiliary pole has a thickness, measured in the direction of travel of the magnetic head, at least five times greater than a corresponding thickness of said main pole.
Claim 11
Dependent Claim
23 words
A magnetic head as claimed in claim 1, wherein said first and second magnet legs comprise discrete lamina to form laminated magnetic layers.
Claim 12
Dependent Claim
26 words
A magnetic head as claimed in claim 10, further comprising a thin, electrically nonconducting layer between each of said discrete lamina of said laminated magnetic layers.
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) | 1992-06-26 | 1992-12-26 | 1993-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-26 | 1996-12-26 | 1997-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-26 | 2000-12-26 | 2001-06-27 | $7700.00 | Window Closed / Lapsed |