US3928908A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of magnetic heads
Assignee: Individual
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Filing: 1973-12-07
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Granted: 1975-12-30
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Expires: 1993-12-07
Abstract
Abstract A method is disclosed in which a pair of electrically nonconducting ferrite pole pieces for use in a magnetic transducing head are assembled together with a non-magnetic separator which defines a transducing gap and in which an electrically conductive film is applied around the pole pieces and the gap. The pole pieces are subsequently encased in non-magnetic material to produce a working face in which the pole pieces and gap are surrounded firstly by the conductive layer and then by the nonmagnetic material. A ferrite block is similarly built up surrounded by a conductive layer and non-magnetic material and the block is then grooved to assume a U-shaped configuration. The assemblies containing the pole pieces and the grooved ferrite block are then brought together so that the U-shaped block forms a yoke for the pole pieces. The block assembly may be further grooved to permit a coil to be introduced over at least one limb of the yoke.
Inventors
- 👤 Derek Frank Case
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:54
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/29; G11B5/187; G11B5/1871; G11B5/193; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49021; Y10T29/49027; Y10T29/4903; Y10T29/49032; Y10T29/49036; Y10T29/49041; Y10T29/49048
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
202 words
A METHOD OF MANUFACTURING A TRANSDUCING HEAD FOR USE IN CONJUNCTION WITH A MAGNETIC RECORDING MEDIUM, THE HEAD HAVING A WORKING FACE ARRANGED TO BE POSITIONED IN USE ADJACENT THE MEDIUM TO CO-OPERATE THEREWITH, THE METHOD INCLUDING THE STEPS OF ASSEMBLING A PAIR OF ELECTRICALLY NON-CONDUCTIVE FERRITE ELEMENTS AND A NON-MAGNETIC SPACER SO AS TO PROVIDE AT THE WORKING FACE MAGNETIC POLE PIECES SEPARATED BY THE NON-MAGNETIC SPACER THE LATTER DEFINING A TRANSDUCING GAP; DEPOSITING AN ELECTRICALLY CONDUCTIVE LAYER OVER THE ASSEMBLED FERRITE ELEMENTS TO PROVIDE A CLOSED ELECTRICALLY CONDUCTIVE LOOP ABOUT AN AXIS SUBSTANTIALLY PERPENDICULAR TO THE WORKING FACE AND SUCH AS TO CIRCUMSCRIBE ONLY THE POLE PIECES AND THE TRANSDUCING GAP AT LEAST IN THE VICINITY OF THE WORKING FACE, FORMING A NON-MAGNETIC BLOCK GROOVED TO RECEIVE THE ASSEMBLED ELEMENTS; INSERTING THE ASSEMBLED ELEMENTS WITH THE CONDUCTIVE LAYER THEREON INTO THE GROOVE WITH THE SPACER BETWEEN THE FERRITE ELEMENTS LAYER PARALLEL TO THE AXIS OF THE GROOVE; APPLYING A PLATE OF NON-MAGNETIC MATERIAL TO BRIDGE THE GROOVE; AND BONDING THE ELEMENTS IN THE BLOCK AND THE PLATE TO FORM AN ASSEMBLY HAVING A FACE IN WHICH THE FERRITE ELEMENTS ARE SEPARATED BY THE TRANSDUCING GAP AND SURROUNDED BY NON-MAGNETIC MATERIAL.
Claim 2
Independent Claim
202 words
A METHOD OF MANUFACTURING A TRANSDUCING HEAD FOR USE IN CONJUNCTION WITH A MAGNETIC RECORDING MEDIUM, THE HEAD HAVING A WORKING FACE ARRANGED TO BE POSITIONED IN USE ADJACENT THE MEDIUM TO CO-OPERATE THEREWITH, THE METHOD INCLUDING THE STEPS OF ASSEMBLING A PAIR OF ELECTRICALLY NON-CONDUCTIVE FERRITE ELEMENTS AND A NON-MAGNETIC SPACER SO AS TO PROVIDE AT THE WORKING FACE MAGNETIC POLE PIECES SEPARATED BY THE NON-MAGNETIC SPACER THE LATTER DEFINING A TRANSDUCING GAP; DEPOSITING AN ELECTRICALLY CONDUCTIVE LAYER OVER THE ASSEMBLED FERRITE ELEMENTS TO PROVIDE A CLOSED ELECTRICALLY CONDUCTIVE LOOP ABOUT AN AXIS SUBSTANTIALLY PERPENDICULAR TO THE WORKING FACE AND SUCH AS TO CIRCUMSCRIBE ONLY THE POLE PIECES AND THE TRANSDUCING GAP AT LEAST IN THE VICINITY OF THE WORKING FACE, FORMING A NON-MAGNETIC BLOCK GROOVED TO RECEIVE THE ASSEMBLED ELEMENTS; INSERTING THE ASSEMBLED ELEMENTS WITH THE CONDUCTIVE LAYER THEREON INTO THE GROOVE WITH THE SPACER BETWEEN THE FERRITE ELEMENTS LAYER PARALLEL TO THE AXIS OF THE GROOVE; APPLYING A PLATE OF NON-MAGNETIC MATERIAL TO BRIDGE THE GROOVE; AND BONDING THE ELEMENTS IN THE BLOCK AND THE PLATE TO FORM AN ASSEMBLY HAVING A FACE IN WHICH THE FERRITE ELEMENTS ARE SEPARATED BY THE TRANSDUCING GAP AND SURROUNDED BY NON-MAGNETIC MATERIAL.
Claim 3
Dependent Claim
28 words
A method of manufacturing a transducing head as claimed in claim 1 further including the step of shaping the face of said assembly to form the working face.
Claim 4
Dependent Claim
41 words
A method of manufacturing a transducing head as claimed in claim 2 further including the step of removing material from that face opposite said working face parallel to and around the spacer to shape the pole pieces into a required configuration.
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) | 1978-12-29 | 1979-06-30 | 1979-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-29 | 1983-06-30 | 1983-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-29 | 1987-06-30 | 1987-12-30 | $7700.00 | Window Closed / Lapsed |