Patent US3700827A successfully refreshed from Google Patents.
US3700827A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic head including thin magnetic film separated by a gap spacer
Assignee: NEC Corp
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Filing: 1971-01-27
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Granted: 1972-10-24
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Expires: 1991-01-27
Abstract
Abstract A thin film magnetic head includes a substrate on which thin film core portions are formed. The core films overlap at one end and a gap spacer is interposed between the overlying ends of the core portions to form a gap having a width defined by a reduced width end portion of one of the core portions and corresponding to the track width.
Inventors
- 👤 Morimasa Nagao
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:29
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/31; G11B5/3176; G11B5/3179; G11B5/3186
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
163 words
A thin film magnetic head comprising a substrate having a side surface facing a magnetic recording medium, a polepiece including first and second opposing magnetic thin films formed on one surface of said substrate and spaced from one another by a gap and terminating flush with said side surface, a magnetic member for coupling between said first and second magnetic thin films, a gap spacer of thin nonmagnetic film interposed between said first and second magnetic thin films and terminating flush with said side surface, and a coil mounted about said magnetic member. said first magnetic thin film extending on one surface of said substrate and having a preselected length in the normal direction to said magnetic recording medium and a width corresponding to a write track width, said gap spacer overlying said first magnetic thin film and said second magnetic thin film overlying said gap spacer on said first magnetic thin film and extending therefrom on said one surface of said substrate.
Claim 2
Dependent Claim
163 words
A thin film magnetic head comprising a substrate having a side surface facing a magnetic recording medium, a polepiece including first and second opposing magnetic thin films formed on one surface of said substrate and spaced from one another by a gap and terminating flush with said side surface, a magnetic member for coupling between said first and second magnetic thin films, a gap spacer of thin nonmagnetic film interposed between said first and second magnetic thin films and terminating flush with said side surface, and a coil mounted about said magnetic member. said first magnetic thin film extending on one surface of said substrate and having a preselected length in the normal direction to said magnetic recording medium and a width corresponding to a write track width, said gap spacer overlying said first magnetic thin film and said second magnetic thin film overlying said gap spacer on said first magnetic thin film and extending therefrom on said one surface of said substrate.
Claim 3
Dependent Claim
64 words
The thin film magnetic head of claim 1, wherein said magnetic member comprises a rigid U-shaped bulk magnetic core, one leg of said U-shaped core being coupled to said first magnetic thin film and the other leg of said U-shaped core being coupled to said second magnetic thin film, said coil being mounted about the portion of said U-shaped core bridging the legs thereof.
Claim 4
Dependent Claim
95 words
The thin magnetic head of claim 1, wherein said substrate includes a hole formed therein from said one surface to an opposed surface, said magnetic member comprising a third magnetic thin film extending on said one surface of said substrate around said hole with one end of said third magnetic thin film being integrally connected to said second magnetic thin film, the other end of said third magnetic thin film partially overlapping and contacting said first magnetic thin film, said coil being mounted about said substrate and said third magnetic thin film through said hole.
Claim 5
Dependent Claim
40 words
THe thin film magnetic head of claim 1, in which said one end portion of said one of said magnetic portions has a reduced width with respect to the remainder thereof, said reduced width corresponding to the write track width.
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) | 1975-10-24 | 1976-04-24 | 1976-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-24 | 1980-04-24 | 1980-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-24 | 1984-04-24 | 1984-10-24 | $7700.00 | Window Closed / Lapsed |