Patent US3770403A successfully refreshed from Google Patents.
US3770403A
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US
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Method of making magnetic head assembly having glass ceramic bonded parts
Assignee: Fujitsu Services Ltd
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Filing: 1971-06-11
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Granted: 1973-11-06
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Expires: 1991-06-11
Abstract
Abstract At least two parts of a magnetic head assembly are bonded together using glass-ceramic material in its ceramic phase.
Inventors
- 👤 K Maries
- 👤 D Case
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:53
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/10; G11B5/105; G11B5/127; G11B5/1272; G11B5/187; G11B5/23; G11B5/235; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49021; Y10T29/49032; Y10T29/49055; Y10T29/49057
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
117 words
A method of making a magnetic head assembly having at least two parts and comprising the steps of: accurately positioning the two parts relative to each other to form a narrow transducing gap between surfaces to be joined; placing a quantity of glassceramic forming material in its glass phase adjacent to or in the transducing gap; and bonding said parts together by subjecting the parts and the material to a heating regime to melt the material to cause the latter to form a glass film covering said surfaces; and continuing the heating so as to convert the film forming material from its glasS phase into the glass-ceramic phase so that the glass ceramic bonds said parts together.
Claim 2
Independent Claim
117 words
A method of making a magnetic head assembly having at least two parts and comprising the steps of: accurately positioning the two parts relative to each other to form a narrow transducing gap between surfaces to be joined; placing a quantity of glassceramic forming material in its glass phase adjacent to or in the transducing gap; and bonding said parts together by subjecting the parts and the material to a heating regime to melt the material to cause the latter to form a glass film covering said surfaces; and continuing the heating so as to convert the film forming material from its glasS phase into the glass-ceramic phase so that the glass ceramic bonds said parts together.
References Cited (Backward Citations)
US3495045A
Cited
US3681044A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-05 | 1977-05-07 | 1977-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-05 | 1981-05-07 | 1981-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-05 | 1985-05-07 | 1985-11-06 | $7700.00 | Window Closed / Lapsed |