US4590530A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic head
Assignee: Panasonic Holdings Corp
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Filing: 1982-11-24
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Granted: 1986-05-20
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Expires: 2002-11-24
Abstract
Abstract A magnetic head a core having a front core and a back core. The front core has a wear-resistant non-magnetic base and a soft magnetic thin film disposed on the base. The thin film is divided into halves by a magnetic gap therein. The back core has a U-shaped block of soft magnetic material and a wear-resistant non-magnetic member connected between the legs of the soft magnetic block. The front and back cores are coupled with each other with the thin film sandwiched therebetween, the magnetic gap in the thin film facing the wear-resistant non-magnetic member, and the soft magnetic thin film and the soft magnetic block being in face-to-face contact with each other out of the neighborhood of the magnetic gap to form a closed magnetic path across the magnetic gap.
Inventors
- 👤 Hiroshi Sakakima
- 👤 Mitsuo Satomi
- 👤 Yukihiro Yanagiuchi
- 👤 Harufumi Senno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 22:11
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/31; G11B5/3103; G11B5/3106
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
194 words
A magnetic head comprising: a front core having a wear-resistant non-magnetic base and a soft magnetic thin film on said base, said thin film being in two parts and having a magnetic gap therebetween; a back core having a U-shaped block of soft magnetic material having magnetic characteristics inferior to those of said thin film and wear resistance characteristics superior to those of said thin film, and a wear-resistant non-magnetic member mounted between the ends of the leg portions of said block, said front core being against the lateral face of said back core adjacent the ends of said legs and having said thin film sandwiched between said back core and said non-magnetic base, the ends of said legs, said non-magnetic member, the edge of said thin film and the side face of said non-magnetic base forming a tape contact face, said magnetic gap facing said wear-resistant non-magnetic member on said back core, said soft magnetic thin film and said soft magnetic block being in face-to-face contact with each other out of the neighborhood of said magnetic gap for forming a closed magnetic path across said magnetic gap; and a winding on said block.
Claim 2
Dependent Claim
194 words
A magnetic head comprising: a front core having a wear-resistant non-magnetic base and a soft magnetic thin film on said base, said thin film being in two parts and having a magnetic gap therebetween; a back core having a U-shaped block of soft magnetic material having magnetic characteristics inferior to those of said thin film and wear resistance characteristics superior to those of said thin film, and a wear-resistant non-magnetic member mounted between the ends of the leg portions of said block, said front core being against the lateral face of said back core adjacent the ends of said legs and having said thin film sandwiched between said back core and said non-magnetic base, the ends of said legs, said non-magnetic member, the edge of said thin film and the side face of said non-magnetic base forming a tape contact face, said magnetic gap facing said wear-resistant non-magnetic member on said back core, said soft magnetic thin film and said soft magnetic block being in face-to-face contact with each other out of the neighborhood of said magnetic gap for forming a closed magnetic path across said magnetic gap; and a winding on said block.
Claim 3
Dependent Claim
18 words
A magnetic head as claimed in claim 1, wherein soft magnetic thin film comprises Sendust or amorphous alloy.
Claim 4
Dependent Claim
27 words
A magnetic head as claimed in claim 1, wherein said soft-magnetic thin film is a multi-layer film comprising soft magnetic layers and an insulator layer or layers.
Claim 5
Dependent Claim
16 words
A magnetic head as claimed in claim 3, wherein said insulator layer is a wear-resistive material.
Claim 6
Dependent Claim
17 words
A magnetic head as claimed in claim 4, wherein said insulator layer comprises a ceramic or glass.
Claim 7
Dependent Claim
19 words
A magnetic head as claimed in claim 3, wherein said insulator layer is thinner than said soft magnetic layer.
Claim 8
Dependent Claim
18 words
A magnetic head as claimed in claim 1, wherein said wear-resistant non-magnetic base comprises a ceramic or glass.
Claim 9
Dependent Claim
15 words
A magnetic head as claimed in claim 1, wherein said U-shaped block comprises a ferrite.
Claim 10
Dependent Claim
22 words
A magnetic head as claimed in claim 1, wherein said wear-resistant non-magnetic member of said back core comprises a ceramic or glass.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-05-19 | 1989-11-18 | 1990-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-19 | 1993-11-18 | 1994-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-19 | 1997-11-18 | 1998-05-20 | $7700.00 | Window Closed / Lapsed |