US4375657A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic head assembly
Assignee: International Business Machines Corp
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Filing: 1980-11-03
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Granted: 1983-03-01
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Expires: 2000-11-03
Abstract
Abstract A magnetic head assembly useful as a write head is formed with a ferrite substrate, having a recessed channel on one surface in which a conductive coil is deposited, and a ferrite closure having a planar surface that is joined to the substrate surface to establish a transducing gap and to enclose the recessed coil. In operation, pulsed write current is applied to the write head and a significant reduction in Joule heating is realized. A low resistance substrate is employed to provide a high saturation flux density.
Inventors
- 👤 George W. Brock
- 👤 Robert N. Hyland
- 👤 Edward J. Pawlowski
- 👤 Frank B. Shelledy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 12:38
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/133; G11B5/17
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
83 words
A ferrite magnetic head assembly comprising: a ferrite magnetic substrate having a configured surface; a recessed channel formed on said configured surface of said substrate; a conductive thin film coil disposed in said channel; a rectangular ferrite magnetic closure section having a planar surface coextensively contiguous with said configured surface for engaging said configured surface and for enclosing said conductive coil; and an insulating layer deposited on said configured surface and between said coil and said configured surface for providing a transducing gap.
Claim 2
Dependent Claim
83 words
A ferrite magnetic head assembly comprising: a ferrite magnetic substrate having a configured surface; a recessed channel formed on said configured surface of said substrate; a conductive thin film coil disposed in said channel; a rectangular ferrite magnetic closure section having a planar surface coextensively contiguous with said configured surface for engaging said configured surface and for enclosing said conductive coil; and an insulating layer deposited on said configured surface and between said coil and said configured surface for providing a transducing gap.
Claim 3
Dependent Claim
26 words
A ferrite magnetic head assembly as in claim 1, wherein said substrate and said closure section serve as pole pieces to define a transducing gap therebetween.
Claim 4
Dependent Claim
20 words
A ferrite magnetic head assembly as in claim 1, wherein said insulating layer determines the length of said transducing gap.
Claim 5
Dependent Claim
36 words
A ferrite magnetic head assembly as in claim 1, including conductive studs attached to the ends of said conductive coil, and electrical leads attached to said studs for conducting signals to and from said head assembly.
Claim 6
Dependent Claim
28 words
A ferrite magnetic head assembly as in claim 1, including a back gap portion delineated by said recessed channel for providing a bearing surface for said closure section.
References Cited (Backward Citations)
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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) | 1986-02-28 | 1986-08-30 | 1987-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-28 | 1990-08-30 | 1991-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-28 | 1994-08-30 | 1995-03-01 | $7700.00 | Window Closed / Lapsed |