Patent US4301353A successfully refreshed from Google Patents.
US4301353A
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US
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Method for producing magnetic head
Assignee: Hitachi Ltd
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Filing: 1980-02-28
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Granted: 1981-11-17
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Expires: 2000-02-28
Abstract
Abstract A method for producing a magnetic head, comprising the step of irradiating peripheral parts other than a track portion and/or a slider portion with a laser beam so as to selectively remove surface parts of the irradiated parts, thereby to form the track portion and/or the slider portion. According to this method, the track portion and/or the slider portion of the magnetic head can be worked at high working rate, at high precision and with low working deformation, with the result that the magnetic head of excellent reproduced output and crosstalk characteristics can be readily manufactured.
Inventors
- 👤 Masahide Suenaga
- 👤 Noboru Shimizu
- 👤 Mitsuhiro Kudo
- 👤 Hiroshi Yamaguchi
- 👤 Masao Mitani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 13:44
CPC Classifications
B; B23; B23K; B23K26/00; B23K26/02; B23K26/06; B23K26/064; B23K26/066; B23K26/36; B23K26/361; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49021; Y10T29/49032; Y10T29/49036; Y10T29/49041
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
85 words
A method for producing a magnetic head comprising the steps of irradiating peripheral parts other than a track portion of a magnetic head core with a laser beam so as to selectively remove a portion of the surface of the irradiated parts, thereby to form said track portion including passing said laser beam through a slit having a predetermined pattern to shape said beam and then focusing the shaped beam onto said magnetic head core to thereby irradiate said peripheral parts with said laser beam.
Claim 2
Independent Claim
85 words
A method for producing a magnetic head comprising the steps of irradiating peripheral parts other than a track portion of a magnetic head core with a laser beam so as to selectively remove a portion of the surface of the irradiated parts, thereby to form said track portion including passing said laser beam through a slit having a predetermined pattern to shape said beam and then focusing the shaped beam onto said magnetic head core to thereby irradiate said peripheral parts with said laser beam.
Claim 3
Dependent Claim
19 words
A method for producing a magnetic head as defined in claim 1, wherein said core is made of ferrite.
Claim 4
Dependent Claim
19 words
A method for producing a magnetic head as defined in claim 1, wherein said slit is made of ceramics.
Claim 5
Dependent Claim
21 words
A method for producing a magnetic head as defined in claim 1, wherein said core is made of a high-permeability alloy.
Claim 6
Dependent Claim
23 words
A method for producing a magnetic head as defined in claim 1, wherein said slit is made of a high-melting point metal material.
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) | 1984-11-16 | 1985-05-18 | 1985-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-16 | 1989-05-18 | 1989-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-16 | 1993-05-18 | 1993-11-17 | $7700.00 | Window Closed / Lapsed |