US3913143A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic head face assembly using chemically machinable glass ceramic bonding means
Assignee: Eastman Kodak Co
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Filing: 1974-01-10
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Granted: 1975-10-14
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Expires: 1994-01-10
Abstract
Abstract Precision-lapped pieces of ceramic and ferrite are stacked together with pieces of ceramic-convertible glass. Firing of the stack causes the glass to devitrify and results in a comb-less track array assembly having precise track and track-to-track dimensions. The assembly is then processed to form part of a magnetic record and/or reproduce head.
Inventors
- 👤 Robert A Schneider
- 👤 Willem L Kroon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:25
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/29; G11B5/187; G11B5/193; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49021; Y10T29/49032; Y10T29/49048; Y10T29/49055; Y10T29/49057
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
109 words
A face assembly for a magnetic record and/or reproduce head having: a. first and second members, each comprising first and second ferrite laminations, glass ceramic between said ferrite laminations and bonding said ferrite laminations, together with said glass ceramic, into an integral assembly said assembly having at least one face exposing parts of both said ferrite laminations; b. means bonding said first and second members together so that the ferrite laminations of said first member align with the ferrite laminations of said second member; and c. means disposed between the aligned ferrite laminations for prividing non-magnetic gaps between the aligned ferrite laminations, said glass ceramic being comprised of Fotoceram.
Claim 2
Dependent Claim
109 words
A face assembly for a magnetic record and/or reproduce head having: a. first and second members, each comprising first and second ferrite laminations, glass ceramic between said ferrite laminations and bonding said ferrite laminations, together with said glass ceramic, into an integral assembly said assembly having at least one face exposing parts of both said ferrite laminations; b. means bonding said first and second members together so that the ferrite laminations of said first member align with the ferrite laminations of said second member; and c. means disposed between the aligned ferrite laminations for prividing non-magnetic gaps between the aligned ferrite laminations, said glass ceramic being comprised of Fotoceram.
Claim 3
Dependent Claim
123 words
A MAGNETIC RECORD AND/OR REPRODUCE HEAD, COMPRISING A. FACE ASSEMBLY AND REAR ASSEMBLY FOR COMPLETING MAGNETIC CIRCUITS DEFINED BY SAID FACE ASSEMBLY, SAID FACE ASSEMBLY COMPRISING: A. FIRST AND SECOND MEMBERS, EACH COMPRISING FIRST AND SECOND FERRITE LAMINATIONS, GLASS CERAMIC BETWEEN SAID FERRITE LAMINATIONS, AND BONDING SAID FERRITE LAMINATIONS, TOGETHER WITH SAID GLASS CERAMIC, INTO AN INTEGRAL ASSEMBLY SAID ASSEMBLLY HAVING LEAST ONE FACE EXPOSING PARTS OF BOTH SAID FERRITE LAMINATIONS, B. MEANS BONDING SAID FIRST AND SECOND MEMBERS TOGETHER SO THAT THE FERRITE LAMINATIONS OF SAID FIRST MEMBER ALIGN WITH THE FERRITE LAMINATIONS OF SAID SECOND MEMBER, AND C. MEANS DISPOSED BETWEEN THE ALIGNED FERRITE LAMINATIONS FOR PROVIDING NON-MAGNETIC GAPS BETWEEN THE ALIGNED FERRITE LAMINATIONS, SAID GLASS CERAMIC BEING COMPRISED OF FOTOCERAM.
Claim 4
Dependent Claim
123 words
A MAGNETIC RECORD AND/OR REPRODUCE HEAD, COMPRISING A. FACE ASSEMBLY AND REAR ASSEMBLY FOR COMPLETING MAGNETIC CIRCUITS DEFINED BY SAID FACE ASSEMBLY, SAID FACE ASSEMBLY COMPRISING: A. FIRST AND SECOND MEMBERS, EACH COMPRISING FIRST AND SECOND FERRITE LAMINATIONS, GLASS CERAMIC BETWEEN SAID FERRITE LAMINATIONS, AND BONDING SAID FERRITE LAMINATIONS, TOGETHER WITH SAID GLASS CERAMIC, INTO AN INTEGRAL ASSEMBLY SAID ASSEMBLLY HAVING LEAST ONE FACE EXPOSING PARTS OF BOTH SAID FERRITE LAMINATIONS, B. MEANS BONDING SAID FIRST AND SECOND MEMBERS TOGETHER SO THAT THE FERRITE LAMINATIONS OF SAID FIRST MEMBER ALIGN WITH THE FERRITE LAMINATIONS OF SAID SECOND MEMBER, AND C. MEANS DISPOSED BETWEEN THE ALIGNED FERRITE LAMINATIONS FOR PROVIDING NON-MAGNETIC GAPS BETWEEN THE ALIGNED FERRITE LAMINATIONS, SAID GLASS CERAMIC BEING COMPRISED OF FOTOCERAM.
References Cited (Backward Citations)
US3760494A
Cited
US3770403A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-13 | 1979-04-14 | 1979-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-13 | 1983-04-14 | 1983-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-13 | 1987-04-14 | 1987-10-14 | $7700.00 | Window Closed / Lapsed |