JPH065645B2 - Superconductor magnetic device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention uses a superconductor to conduct magnetic flux without leakage or attenuation and to change the cross-sectional area to converge or disperse the magnetic field. The present invention relates to a magnetic device including a conduit.

<Prior Art> Conventionally, when conducting a magnetic flux or concentrating or converging the magnetic flux, a technique using a magnetic material having a high magnetic permeability such as silicon steel, permalloy, or ferrite has been generally used.
FIG. 3 shows a conventional example in which a magnetic field is converged by a high-permeability material 4. In the magnetic field 1, the cross-sectional area of the central portion 5 is reduced and the cross-sectional areas of both end portions 6 are increased. The magnetic permeability material 4 is placed and the magnetic flux is converged at the central portion thereof. As an example, even if soft iron is used for the high magnetic permeability material 4, its magnetic permeability is remarkably larger than that of air, so that the magnetic flux could be converged and conducted. As the high magnetic permeability material, there have been transformer cores made of silicon steel or the like, motor magnetic cores, or small coils or transformers made of ferrite or the like, or magnetic head cores.

<Problems to be Solved by the Invention> When a magnetic material having a high magnetic permeability conducts or converges a magnetic flux, the magnetic material has a considerably high magnetic permeability, but in reality, the magnetic material has a finite magnetic permeability. , The magnetic flux was leaking.
The ratio of the magnetic flux passing through the magnetic material and the magnetic flux leaking through the air is
It changes depending on the ratio of the magnetic permeability of the magnetic material and air, and the shape of the magnetic circuit composed of the magnetic material, so the magnetic flux transmissivity is reduced by the leakage magnetic flux, the external noise magnetic field is spread, and the frequency used is When it was high, it could be a source of harm such as loss due to eddy current in the core and noise generation due to electromagnetic induction.

The present invention solves the problems of the conventional magnetic circuit using a magnetic material, and provides a conduit for magnetic flux that does not cause problems such as leakage of magnetic flux and noise.

<Means for Solving the Problem> The present invention relates to a superconductor, particularly a recently developed high temperature superconductor,
Conduction without leakage of magnetic flux by the Meissner effect of
The present invention relates to a magnetic circuit that converges.

Since the superconductor is completely diamagnetic, the magnetic field does not penetrate.
Therefore, the superconducting conduit having a shape that does not reflect or scatter the magnetic flux can conduct the internal magnetic flux without leaking, and the magnetic flux density therein can be made inversely proportional to the cross-sectional area of the conduit. At least one place in this flux conduit,
By forming a thin insulating layer that blocks the current over the entire length along the magnetic flux, the current induced in the conduit due to the change in the magnetic flux does not flow in a loop through the tube diameter.

With the above-described magnetic flux conduit, it is possible to conduct the magnetic flux without leaking it, and to prevent the induction current from flowing through the conduit to affect the internal magnetic flux.

<Operation> In the present invention, at least the inside of a conduit that conducts magnetic flux is formed of a superconductor to prevent the magnetic flux from scattering and reflecting, thereby eliminating leakage and reflection of the magnetic flux from the conduit, and Since the induction current that influences the magnetic flux due to the magnetic flux does not flow, the magnetic flux can be effectively used in the superconductor magnetic device using this conduit. Also, noise due to electromagnetic induction is not emitted to the outside of this device, and no external noise radio wave is allowed to enter the inside of the conduit of the magnetic flux inside this device. Therefore, even if the device of the present invention is used in close proximity, problems such as crosstalk do not occur.

<Example> An example of the present invention will be described with reference to the drawings.

The longitudinal section in FIG. 1 and the aa 'transverse section in FIG. 1 show the first embodiment which is the basic constitution of the magnetic device of the present invention. This corresponds to the conventional example in the figure. These figures show a cylindrical flux conduit 2 with a thin insulating layer 3 along the length of the centrally tapered superconductor conduit 2.

The magnetic flux conduit 2 can be manufactured by a film forming technique because it only needs to have a superconductor layer having a thickness of about 10 ⁻⁷ m or more, which is equal to or more than the depth of penetration of a magnetic field into the superconductor.

In the embodiment, an yttrium-barium-copper oxide (Y-Ba-Cu-O) having a critical temperature Tc of about 90K is formed on the inner surface of an alumina molded product (not shown) having a shape in which a conduit is cut vertically.
Was deposited in the form of a film having a thickness of 10 μm by a sputtering method and heat-treated in air. The formed alumina molded product having the superconductor film was bonded at the thin insulating layer 3 portion with an insulating adhesive to prepare the conduit 2.

The conduit 2 of the present invention can use zirconia, silica, etc. in addition to the alumina used in the first embodiment,
In addition, a CVD method, a vapor deposition method, or the like can be used for forming the film, and a superconductor other than Y-Ba-Cu-O can be used.

In the produced conduit 2, when the magnetic flux 1 is introduced from the left side as shown in FIG. 1, the magnetic flux 1 does not leak even in the central portion of the conduit due to the Meissner effect, so that the magnetic flux density can be increased. (However, the critical magnetic field is not more than the critical magnetic field.) Since the thin insulating layer 3 is provided on the superconductor of the conduit 2 over the entire length thereof, even if the internal magnetic flux 1 changes, the magnetic field that affects the magnetic flux 1. The induced current for generating does not flow. Since the insulating layer 3 is thin, there is no problem such as leakage of the magnetic flux 1.

4 and 5 are a sectional view of a second embodiment in which the present invention is applied to the transformer 14 and a sectional view taken along the line bb 'of the conduit. A hollow donut-shaped superconductor conduit 2 has an insulating layer 3 of the conduit formed on the entire length of the conduit.

When a current i _{1 is} passed through this input coil 7, a magnetic flux 1 generated
Are completely reflected by the inner surface of the hollow donut-shaped conduit 6, so that they all penetrate the output coil 8 and generate an induced current i ₂ .

Since the transformer 14 of the present invention has no conventional magnetic core, there is no loss due to the eddy current generated in the conventional core. Since the conduit 2 is provided with the insulating layer 3, no induced current affecting the magnetic flux 1 flows in the conduit 2. Moreover, due to the leakage of magnetic flux from the transformer 14, no noise electromagnetic wave is emitted to the outside of the transformer, and no electromagnetic wave is entered from the outside.
If the input coil 7 and the output coil 8 of this transformer are made of the same superconducting wire or foil, no loss occurs in the current of the coil or in the conduit of the magnetic flux, so that the conversion efficiency is 1
A 00% transformer can be produced.

Also in the transformer 14 of the second embodiment, the magnetic flux conduit 2 of the superconductor can be manufactured by the method of the first embodiment.

FIG. 6 is a sectional view of a third embodiment in which the present invention is applied to a magnetic head, and FIG. 7 is a sectional view taken along the line cc 'of FIG. The conduit 2 of the magnetic head 15 was also manufactured by the method of bonding after forming the superconductor film in the insulating layer 3 portion as in the first embodiment. The magnetic head 15 of FIG. 6 is used for writing and reading the magnetic recording film 10 of the magnetic tape 9, and at least the inner surface except the magnetic fine opening 13 and the insulating layer 3 on the contact side with the magnetic tape. Is composed of a magnetic conduit 2 made of a superconductor. The magnetic flux 1 generated by the magnetic pole recorded on the magnetic tape 9 enters through one of the openings 13 of the magnetic head and exits through the other without leaking. Therefore, if the coil 11 is provided in the conduit 1 of the superconductor, the magnetic tape can be recorded with the magnetic flux 1.
Changes and is detected as an induced current in the coil 11. When recording on the magnetic tape 9, contrary to the above, if a recording current is passed through the coil 11, the magnetic flux 1 in the magnetic head 15
Thus, the magnetic flux 1 is completely guided to the magnetic tape by the superconducting conduit to magnetize and record the magnetic recording material. When the magnetic head 15 is read-only, the coil 11 can be a small magnetic sensor, and the magnetic head 15 can be downsized. 8th
FIG. 9 and FIG. 9 show another embodiment of the magnetic head (FIG. 9 is a sectional view taken along the line d--d 'in FIG. 8), which is the fourth embodiment. A block of a superconductor is processed, and an insulating layer 3 is provided inside the path of the magnetic flux 1 and the entire length along the magnetic flux 1, and the opening on the side that comes into contact with the tape 9 is moved relative to the tape.
In this configuration, a small magnetic sensor 12 is incorporated into a superconducting conduit 2 which is a superconducting partition wall divided into two parts. The magnetic flux 1 of the magnetic tape entering from one opening completely exits from the other opening, but the magnetic head 15 can be small in size, have a short path for the magnetic flux 1, and be efficient.

As described above, since the magnetic head 15 of the present invention has no magnetic core, there is no loss due to the eddy current generated by the signal magnetic flux as in the prior art, and the insulating layer 3 is provided. Since there is no induced current due to the internal magnetic flux,
In principle, sensitivity does not decrease even at extremely high frequencies.

Further, since the magnetic head 15 is constituted by the superconducting conduit 2, no noise electromagnetic wave is emitted to the outside or noise electromagnetic wave from the outside enters. The gap of the magnetic head 15 currently used is about μm. This is manufactured by a method in which molten glass is sandwiched between magnetic materials, but the magnetic head 15 of the present invention may also be formed of a magnetic material only in the portion of the gap 13 in contact with the magnetic tape.

The above is the description of the magnetic head 15 for horizontal recording.
By changing the shape and arranging the openings of the conduit 2 above and below the magnetic tape, the magnetic head 15 for perpendicular recording can be obtained.

FIG. 10 shows an example of a cross section of the superconductor conduit 2 other than the above example. FIG. 10 (a) is an example in which the superconductor of the conduit 2 has a portion overlapping with the insulating layer 3 interposed therebetween, and FIG. 10 (b) shows the insulating layer 3 obliquely with respect to the center of the superconductor layer conduit 2. This is an example in which the number of conduits is increased and the number of conduits is also increased. FIG. 7C is an example of the conduit 2 having a rectangular cross section. By forming the insulating layer 3 as in the cross section of the example of FIG. 10, the leakage of magnetic flux can be further reduced.

<Effects of the Invention> The superconductor magnetic device of the present invention uses a magnetic flux conduit of a superconductor having an insulating layer that does not flow an induction current due to the magnetic flux, thereby conducting the magnetic flux without leaking it. There is no need, and there is no mixing of electromagnetic waves from the outside. Therefore, the magnetic flux can be efficiently transmitted up to the high-frequency region, and a superconductor magnetic device in which noise is not mixed can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of a first embodiment of the present invention, and FIG.
FIG. 3 is a sectional view taken along the line aa 'in FIG. 3, FIG. 3 is an explanatory view of a conventional example using a magnetic material, FIG. 4 is a sectional view of a second embodiment of the present invention, and FIG. Sectional view, FIG. 6 is a sectional view of a third embodiment of the present invention, FIG. 7 is a sectional view taken along the line cc 'of FIG. 6, and FIG.
FIG. 9 is a sectional view of a fourth embodiment of the present invention, FIG. 9 is a sectional view taken along the line d--d 'of FIG. 8, and FIGS. 10 (a), (b) and (c) are sectional views of other conduits. It is the figure which showed the example of. 1 is a magnetic flux, 2 is a superconductor conduit, 3 is an insulating layer, 4 is a magnetic material, 5 is a central portion of the magnetic material, 6 is an end portion of the magnetic material, 7
Is the input coil of the transformer, 8 is the output coil of the transformer,
Reference numeral 9 is a magnetic tape, 10 is a magnetic recording film, 11 is a coil of a magnetic head, 12 is a magnetic sensor, 13 is a gap of the magnetic head, 14 is a transformer, and 15 is a magnetic head.

Claims (5)

[Claims] 1. A superconducting tube having at least an inner surface having a thickness of a superconductor which is equal to or greater than the depth of an intrusion magnetic field of the Meissner effect, and which allows a magnetic flux entering from one side to pass without being scattered or reflected. A superconducting magnetic device, characterized in that the body is provided with a thin insulating layer for interrupting current at least at one location along the length of the conduit along the magnetic flux. 2. The superconductor magnetic device according to claim 1, wherein the cross-sectional area or shape of the magnetic flux conduit is not constant. 3. The superconductor magnetic device is formed in an annular shape, and is provided with a set of input and output coils through which all magnetic fluxes in the superconductor magnetic device penetrate. The superconductor magnetic device according to claim 1 or 2. 4. The structure according to claim 1, wherein the openings at both ends of the conduit of the superconductor magnetic device are arranged so as to have both polarities of magnetic polarization recorded on the magnetic recording medium.
The superconductor magnetic device according to the second aspect. 5. The superconductor according to claim 1, 2, 3, or 4, wherein a magnetic sensor for detecting magnetic flux is provided in the superconductor magnetic device. Body magnetic device.