US3893189A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic record/reproduce head and manufacturing method therefor
Assignee: Eastman Kodak Co
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Filing: 1974-01-14
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Granted: 1975-07-01
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Expires: 1994-01-14
Abstract
Abstract Arrays for use in the manufacture of magnetic record and/or reproduce heads are provided by stacking laminations of ceramicconvertible glass which has been chemically machined to provide apertures in the laminations. The ''''apertured'''' laminations act as holders for ferrite and ceramic pieces. When the glass is fired, it devitrifies, resulting in the laminations, ferrite, and ceramic fusing into an integral assembly which may then be further processed into one or more magnetic heads.
Inventors
- 👤 Willem L Kronn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:08
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/133; G11B5/1335; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49021; Y10T29/49032; Y10T29/49055; Y10T29/49057
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
113 words
An assembly for a magnetic record and/or reproduce head made by the process of: a. machining at least one aperture in a lamination of ceramic-convertible glass of the type which is machineable; b. placing a ferrite member within said aperture; c. sandwiching said glass and ferrite assemblage between a pair of laminations of ceramic-convertible glass; d. machining at least one aperture in each of said pair of laminations of ceramic-convertible glass; e. placing a ceramic spacer within each of the laSt-named apertures so that said spacers may abut against said ferrite member; and f. firing the whole assemblage to cause said glass to devitrify into ceramic while pressing said spacers against said ferrite.
Claim 2
Dependent Claim
113 words
An assembly for a magnetic record and/or reproduce head made by the process of: a. machining at least one aperture in a lamination of ceramic-convertible glass of the type which is machineable; b. placing a ferrite member within said aperture; c. sandwiching said glass and ferrite assemblage between a pair of laminations of ceramic-convertible glass; d. machining at least one aperture in each of said pair of laminations of ceramic-convertible glass; e. placing a ceramic spacer within each of the laSt-named apertures so that said spacers may abut against said ferrite member; and f. firing the whole assemblage to cause said glass to devitrify into ceramic while pressing said spacers against said ferrite.
Claim 3
Dependent Claim
26 words
The assembly of claim 1 modified by the additional step of shaping said ferrite member, before it is placed within its aperture, to provide pole projections.
Claim 4
Independent Claim
156 words
The method of making an array useful in the manufacture of a magnetic record and/or reproduce head, comprising the steps of: a. abutting a first lamination of ceramic-convertible glass having an aperture, and a ceramic spacer within said aperture, against a base; b. placing a second lamination of ceramic-convertible glass having an aperture, and a ferrite member within said aperture, in contact with said first lamination so that said spacer and ferrite are in contact with each other; c. placing a third lamination of ceramic-convertible glass having an aperture, and a ceramic spacer within said aperture, so that (1) the spacer within the aperture of said third lamination and said ferrite are in contact with each other, and (2) said second lamination is sandwiched between said first and third laminations; d. sandwiching said three laminations between said base and a cap; and e. devitrifying said glass into ceramic, whereby said sandwiches fuse into an integral assembly.
Claim 5
Independent Claim
156 words
The method of making an array useful in the manufacture of a magnetic record and/or reproduce head, comprising the steps of: a. abutting a first lamination of ceramic-convertible glass having an aperture, and a ceramic spacer within said aperture, against a base; b. placing a second lamination of ceramic-convertible glass having an aperture, and a ferrite member within said aperture, in contact with said first lamination so that said spacer and ferrite are in contact with each other; c. placing a third lamination of ceramic-convertible glass having an aperture, and a ceramic spacer within said aperture, so that (1) the spacer within the aperture of said third lamination and said ferrite are in contact with each other, and (2) said second lamination is sandwiched between said first and third laminations; d. sandwiching said three laminations between said base and a cap; and e. devitrifying said glass into ceramic, whereby said sandwiches fuse into an integral assembly.
Claim 6
Dependent Claim
134 words
The method of claim 3, including the additional steps of: a. so placing a fourth lamination of ceramic-convertible glass having an aperture that the spacer within the aperture of said third lamination extends into the aperture of said fourth lamination; b. placing a fifth lamination of ceramic-convertible glass having an aperture, and a ferrite member within said aperture, in contact with said spacer extending through the aperture of said fourth lamination; and c. placing a sixth lamination of ceramic-convertible glass having an aperture, and a ceramic spacer within said aperture, in contact with said fifth lamination so that the ferrite member thereof is sandwiched between the spacer extending through the aperture of said fourth lamination and the spacer of said sixth lamination; whereby when said glass laminations are devitrified, a multitrack array is formed.
Claim 7
Dependent Claim
36 words
The method of claim 4, including the additional step of placing spacer material between said third and fourth laminations for defining a space within said array which may house a magnetic shield between said ferrite members.
Claim 8
Dependent Claim
18 words
The method of claim 4, including the additional step of pre-forming both said ferrite members with pole projections.
Claim 9
Dependent Claim
17 words
The method of claim 3, including the additional step of pre-forming said ferrite member with pole projections.
Claim 10
Independent Claim
151 words
The method of making a batch of arrays useful in the manufacture of magnetic record and/or reproduce heads, comprising the steps of: a. producing first and second laminations of ceramic-convertible glass having respective pluralities of apertures therein; b. placing ceramic spacers in at least some of the apertures of both said laminations; c. producing a third lamination of ceramic-convertible glass having a plurality of apertures; d. placing ferrite members in at least some of said apertures of said third lamination; e. sandwiching said third lamination between said first and second laminations so that at least some of said ferrite members are contacted by a ceramic spacer from both of said first and second laminations; f. firing said sandwich so that said glass devitrifies into ceramic, thereby causing said sandwich to fuse into an integral assemblage; and g. dicing said assemblage into a plurality of elements comprising ferrite sandwiched between ceramic parts.
Claim 11
Independent Claim
151 words
The method of making a batch of arrays useful in the manufacture of magnetic record and/or reproduce heads, comprising the steps of: a. producing first and second laminations of ceramic-convertible glass having respective pluralities of apertures therein; b. placing ceramic spacers in at least some of the apertures of both said laminations; c. producing a third lamination of ceramic-convertible glass having a plurality of apertures; d. placing ferrite members in at least some of said apertures of said third lamination; e. sandwiching said third lamination between said first and second laminations so that at least some of said ferrite members are contacted by a ceramic spacer from both of said first and second laminations; f. firing said sandwich so that said glass devitrifies into ceramic, thereby causing said sandwich to fuse into an integral assemblage; and g. dicing said assemblage into a plurality of elements comprising ferrite sandwiched between ceramic parts.
Claim 12
Dependent Claim
21 words
The method of claim 8, including the additional step of pre-forming at least some of said ferrite members with pole projections.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-30 | 1978-12-30 | 1979-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-30 | 1982-12-30 | 1983-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-30 | 1986-12-30 | 1987-07-01 | $7700.00 | Window Closed / Lapsed |