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US3987487A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic transducer with single turn winding structure

Assignee: Sagem SA
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Filing: 1974-12-19
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Granted: 1976-10-19
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Expires: 1994-12-19
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Abstract

Abstract The transducer device for reading or writing information on a magnetic surt comprises an insulating plate on one surface of which is deposited in thin layer form a magnetic circuit having an air gap and a conducting metal forming a turn. The turn is short circuited and the transducer device comprises a discrete magnetic circuit whereon is wound a winding and the turn is a primary or secondary winding of the circuit. It can be used as a reading or writing head for a magnetic disc.

Inventors

  • 👤 Henri Berger

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 07:06
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/17; G11B5/31; G11B5/3103

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 253 words
A trandsucer device for reading or writing information on a magnetic medium comprising: an insulating plate including at least one substantially planar surface that terminates at an edge which, in operation, is disposed in proximity to the said magnetic medium, a plurality of thin layers deposited on the substantially planar surface, said layers comprising: a first layer of magnetic material deposited on the said substantially planar surface near said edge thereof; a layer of conducting metal, having a substantially zero permeability, deposited (1) on a portion of said first layer which is adjacent to said edge so as to cover said portion and to leave a further portion of said first layer which is not covered and (2) on said substantially planar surface of the plate, said layer of conducting material forming a turn which is closed upon itself; and a second layer of said magnetic material deposited (1) on the portion of the layer of conducting material which covers the first layer of magnetic material and (2) on the portion of the first layer of magnetic material which is not covered by the layer of conducting material, and a discrete magnetic circuit whereon is wound a reading/writing winding, said discrete circuit including a longitudinally extending branch which is surrounded by said turn, said plate including at least one opening therein one end of which terminates in said substantially planar surface, said layer of conducting material surrounding said end, and said longitudinally extending branch of said discrete magnetic circuit extending through said opening.
Claim 2
Dependent Claim 253 words
A trandsucer device for reading or writing information on a magnetic medium comprising: an insulating plate including at least one substantially planar surface that terminates at an edge which, in operation, is disposed in proximity to the said magnetic medium, a plurality of thin layers deposited on the substantially planar surface, said layers comprising: a first layer of magnetic material deposited on the said substantially planar surface near said edge thereof; a layer of conducting metal, having a substantially zero permeability, deposited (1) on a portion of said first layer which is adjacent to said edge so as to cover said portion and to leave a further portion of said first layer which is not covered and (2) on said substantially planar surface of the plate, said layer of conducting material forming a turn which is closed upon itself; and a second layer of said magnetic material deposited (1) on the portion of the layer of conducting material which covers the first layer of magnetic material and (2) on the portion of the first layer of magnetic material which is not covered by the layer of conducting material, and a discrete magnetic circuit whereon is wound a reading/writing winding, said discrete circuit including a longitudinally extending branch which is surrounded by said turn, said plate including at least one opening therein one end of which terminates in said substantially planar surface, said layer of conducting material surrounding said end, and said longitudinally extending branch of said discrete magnetic circuit extending through said opening.
Claim 3
Dependent Claim 17 words
A device according to claim 1 wherein the general configuration of the said turn is substantially square.
Claim 4
Dependent Claim 16 words
A device according to claim 1 wherein the general configuration of the said turn is circular.
Claim 5
Dependent Claim 17 words
A device according to claim 1 wherein the general configuration of the said turn is substantially rectangular.
Claim 6
Dependent Claim 14 words
A device according to claim 1 wherein the plate is made from ceramic material.
Claim 7
Dependent Claim 17 words
A device according to claim 1 wherein the discrete magnetic circuit is made from a ferrite-based material.
Claim 8
Dependent Claim 35 words
A device according to claim 1 wherein the conducting metal forming the said turn is copper and wherein the magnetic material is an alloy containing about 80% by weight nickel and 20% by weight iron.
Claim 9
Dependent Claim 55 words
A device according to claim 1 wherein said plate has a second opening therein one end of which terminates in said substantially planar surface, said one end of said second opening being located externally of said turn, and wherein the discrete magnetic circuit includes a further longitudinally extending branch which extends through said second opening.
Claim 10
Dependent Claim 39 words
A device according to claim 8 wherein the discrete magnetic circuit has a first transverse branch which interconnects first ends of said longitudinally extending branches so that first traverse branch forms an unitary member with said longitudinally extending branches.
Claim 11
Dependent Claim 48 words
A device according to claim 9 wherein the said discrete magnetic circuit has a second transverse branch whereon is wound the said winding whereby this second transverse branch interconnects the second ends of the two longitudinal branches in such a way as to close the said magnetic circuit.
Claim 12
Dependent Claim 231 words
A transducer device for reading or writing information on a magnetic medium comprising: an insulating plate including at least one substantially planar surface which terminates at an edge which, in operation, is located near the said magnetic medium, said plate including at least one opening therein which terminates at one end thereof in said substantially planar surface, a plurality of thin layers deposited on the substantially planar surface, said layers comprising: a first layer of magnetic material deposited on the said substantially planar surface near said edge thereof; a layer of a conducting metal, having substantially zero permeability, deposited (1) on a portion of said first layer which is adjacent to said edge so as to cover said portion and to leave a further portion of said layer which is not covered, and (2) on the said substantially planar surface of the plate, said layer of conducting metal forming a turn which is closed upon itself and surrounds said end of said opening; and a second layer of said magnetic material deposited on the portion of the layer of conducting metal which covers the first layer of magnetic material and on the portion of said first layer which is not covered by the layer of conducting metal, and a discrete magnetic circuit whereon is wound a reading/writing winding, said discrete magnetic circuit including a longitudinal branch which extends through said opening.
Claim 13
Dependent Claim 231 words
A transducer device for reading or writing information on a magnetic medium comprising: an insulating plate including at least one substantially planar surface which terminates at an edge which, in operation, is located near the said magnetic medium, said plate including at least one opening therein which terminates at one end thereof in said substantially planar surface, a plurality of thin layers deposited on the substantially planar surface, said layers comprising: a first layer of magnetic material deposited on the said substantially planar surface near said edge thereof; a layer of a conducting metal, having substantially zero permeability, deposited (1) on a portion of said first layer which is adjacent to said edge so as to cover said portion and to leave a further portion of said layer which is not covered, and (2) on the said substantially planar surface of the plate, said layer of conducting metal forming a turn which is closed upon itself and surrounds said end of said opening; and a second layer of said magnetic material deposited on the portion of the layer of conducting metal which covers the first layer of magnetic material and on the portion of said first layer which is not covered by the layer of conducting metal, and a discrete magnetic circuit whereon is wound a reading/writing winding, said discrete magnetic circuit including a longitudinal branch which extends through said opening.
Claim 14
Dependent Claim 173 words
A transducer element for a transducer which is adapted to read or write information on a magnetic medium, said element comprising: an insulating plate including, at least one substantially planar surface which terminates at an edge which, in operation, is to be located adjacent to the said magnetic medium, and a plurality of thin layers deposited on the substantially planar surface, said layers comprising: a first layer of magnetic material deposited on the said substantially planar surface near said edge thereof; a layer of a conducting metal, having substantially zero permeability, deposited on a portion of said first layer adjacent to the said edge and on said substantially planar surface of the plate, said layer of conducting metal defining a turn having a closed geometrical configuration; and a second layer of said magnetic material deposited on the portion of the layer of conducting metal which covers the first layer of magnetic material and on the portion of the first layer of magnetic material which is not covered by the layer of conducting metal.
Claim 15
Dependent Claim 173 words
A transducer element for a transducer which is adapted to read or write information on a magnetic medium, said element comprising: an insulating plate including, at least one substantially planar surface which terminates at an edge which, in operation, is to be located adjacent to the said magnetic medium, and a plurality of thin layers deposited on the substantially planar surface, said layers comprising: a first layer of magnetic material deposited on the said substantially planar surface near said edge thereof; a layer of a conducting metal, having substantially zero permeability, deposited on a portion of said first layer adjacent to the said edge and on said substantially planar surface of the plate, said layer of conducting metal defining a turn having a closed geometrical configuration; and a second layer of said magnetic material deposited on the portion of the layer of conducting metal which covers the first layer of magnetic material and on the portion of the first layer of magnetic material which is not covered by the layer of conducting metal.
Claim 16
Dependent Claim 27 words
An element according to claim 12 wherein said plate has at least one opening therein which terminates within said turn so that said turn surrounds said opening.
Claim 17
Dependent Claim 31 words
An element according to claim 13 wherein the said plate has at least one further opening which opens into said planar surface at a location which is external of said turn.

References Cited (Backward Citations)

US3789158A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-10-19 1980-04-19 1980-10-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-10-19 1984-04-19 1984-10-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-10-19 1988-04-19 1988-10-19 $7700.00 Window Closed / Lapsed

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