JP6567334B2 - Multilayer superconducting coil device - Google Patents

Description

  Embodiments described herein relate generally to a laminated superconducting coil device in which high-temperature superconducting coils are laminated.

In recent years, research on high-temperature superconducting coils using a high-temperature superconducting wire typified by REBCO wire using (RE) Ba ₂ Cu ₃ O ₇ including rare earth (RE) has been actively conducted.

In particular, a high-temperature superconducting wire (hereinafter referred to as “thin film tape wire”) produced by forming a plurality of types of layers on a substrate having a thickness of about 100 μm has a large current capacity under a high magnetic field. There is.
Therefore, realization of a high-temperature superconducting coil having a high current density and a high allowable stress necessary for generating a high magnetic field is expected.

The methods for forming high-temperature superconducting coils that are put into practical use can be broadly classified into several groups depending on the method of winding the thin film tape wire.
A typical example of these forming methods is a method of laminating a plurality of superconducting coils in which thin film tape wires are concentrically wound in the winding axis direction to form one laminated high temperature superconducting coil.
Adjacent superconducting coils are electrically connected with either one of the innermost circumference or the outermost circumference with a metal plate installed in a stepwise manner.
All the superconducting coils stacked form one path through which the superconducting current flows by this metal plate.

Generally, an external force is applied to a superconducting coil by a magnetic field generated by itself.
If the superconducting coil deviates from the specified position due to this external force, the intensity distribution of the magnetic field deviates from the designed intensity distribution.
In addition, even when the superconducting coil is deformed due to thermal contraction during cooling, the superconducting coil is displaced from the specified position, and the intensity distribution of the magnetic field deviates from the designed intensity distribution.
In addition, when quenching occurs due to such deviation or deformation of the superconducting coil, the generated magnetic field cannot be maintained.
In order to prevent this shift and deformation, when using a low-temperature superconducting coil as in the prior art, it is desirable to bond the superconducting coils that are stacked and adjacent to each other.
In addition to adhesion, the low temperature superconducting coil may reinforce the prevention of this shift by pressing flanges movably provided at the upper and lower ends in the central axis direction against the superconducting coil.
Note that it is desirable that adjacent superconducting coils are bonded to each other also from the viewpoint of improving the conductivity of the cold heat.

Fixation of the position of the superconducting coils laminated in this way is similarly required for a superconducting coil manufactured with a thin film tape wire.
In the thin film tape wire as well, it is necessary to prevent disappearance of the generated magnetic field due to quenching and to prevent the generated magnetic field from being distorted out of the designed intensity distribution.
When the generated magnetic field is distorted, a portion having a low strength such as a connection portion between the superconducting coils may be destroyed, and in the worst case, it is burned out.

Japanese Patent No. 2745780 JP 2010-219226 A

However, the above-described thin film tape wire has a high frequency of production, and thus the frequency of including defects is higher than that of the low temperature superconducting coil.
Therefore, the frequency at which the superconducting coil needs to be replaced increases even at the stage where the manufacturing process of the laminated superconducting coil device has advanced, such as during a magnetic field output test.

However, since each layer such as an oxide superconducting layer included in the thin film tape wire is fragile, the superconducting characteristics are easily deteriorated by a minute external force.
That is, if the superconducting coil is firmly bonded to another adjacent superconducting coil, there is a problem that all superconducting coils must be replaced without being able to be partially replaced.
Also, from the viewpoint of preventing separation of each layer due to deformation of the superconducting coil, it is not preferable to firmly bond the superconducting coils to inhibit free deformation.

  The present invention has been made in consideration of such circumstances, and a laminated superconducting coil device capable of suppressing deviation from a specified position of each laminated high temperature superconducting coil and easily exchanging a part thereof. I will provide a.

The laminated superconducting coil device according to the present embodiment is disposed along a winding member in which a plurality of superconducting coils each having a high-temperature superconducting wire wound thereon are laminated in the winding axis direction, and the innermost circumferential surface of the superconducting coil. A cylindrical member penetrating the winding member in the winding axis direction, a flange fixed to the cylindrical member so as to face at least one end surface of the winding member in the winding axis direction, and the flange in the winding axis direction A pressing member that is movably fixed and pressed against an end surface; and a dispersion plate that is provided on the end surface and disperses the pressure applied to the end surface by the pressing member. The distribution plate includes a coil spring and a thin plate. It is provided with at least one spring material selected from the group consisting of a spring and a disc spring, and at least a part of the contact surface that comes into contact with another adjacent high-temperature superconducting coil of the superconducting coil to be laminated is weakened by non-adhesion or demolding treatment. For bonding Is shall.

  According to the present invention, there is provided a laminated superconducting coil device capable of suppressing deviation from a specified position of a plurality of laminated high temperature superconducting coils and easily exchanging a part thereof.

The composition perspective view of the thin film tape wire of the superconducting coil concerning an embodiment. The schematic perspective view of the superconducting coil used suitably by embodiment. 1 is a schematic cross-sectional perspective view of a multilayer superconducting coil device according to a first embodiment. (A) is a schematic front sectional view of the multilayer superconducting coil device according to the second embodiment, and (B) is a schematic front sectional view showing a modification of the multilayer superconducting coil device according to the second embodiment. (A) is a schematic front sectional view of the multilayer superconducting coil device according to the third embodiment, and (B) is a top sectional view of the I-I section of the multilayer superconducting coil device shown in (A). The schematic front sectional drawing of the laminated superconducting coil apparatus concerning 4th Embodiment. (A) is a schematic perspective view of a double pancake coil, (B) is a schematic perspective view of a solenoid coil, and (C) is a schematic top view of a racetrack coil.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
First, the thin film tape wire 20 is demonstrated using the structure perspective view of the thin film tape wire 20 of the superconducting coil 11 concerning embodiment of FIG.
The thin film tape wire 20 is a tape-like wire material including an oxide superconducting layer 25 made of, for example, a second generation RE-based high-temperature superconducting material.

  The thin film tape wire 20 is formed on the substrate 22 made of a high-strength metal material such as a nickel-base alloy, stainless steel, or copper, and when the substrate 22 and the oxide superconducting layer 25 are thermally contracted. An intermediate layer 24 that prevents thermal distortion caused by it, an alignment layer 23 made of magnesium or the like for aligning the intermediate layer 24 on the surface of the substrate 22, and an oxide superconducting layer made of an oxide formed on the intermediate layer 24 25, a protective layer 26 that is composed of silver, gold, platinum, or the like, protects the oxide superconducting layer 25 by preventing oxygen contained in the oxide superconducting layer 25 from diffusing from the oxide superconducting layer 25, and copper Alternatively, the stabilization layer 21 is a highly conductive metal such as aluminum and serves as a detour path for excess current to the oxide superconducting layer 25 to prevent a quench phenomenon.

However, the kind and number of each layer which comprise the thin film tape wire | line 20 are not limited to this, You may increase or decrease as needed. Also, the present invention is not limited to the REBCO wire having such a layer structure, but may be a BSCCO wire made of an oxide superconductor filament or an MgB2 wire.
These layers constituting the thin film tape wire 20 are easily peeled off by a minute stress, and the superconductivity becomes unstable.

FIG. 2 is a schematic perspective view of a superconducting coil 11 that is preferably used in the embodiment.
As shown in FIG. 2, the thin film tape wire 20 is wound around the winding frame 13 concentrically around the winding axis C with both side edges in the tape width direction aligned, and is called a so-called pancake coil. The superconducting coil 11 is used.
A plurality of the high-temperature superconducting coils 11 (hereinafter simply referred to as “superconducting coils 11”) are stacked in the winding axis direction C and accommodated in, for example, a cooler (not shown) to form a superconducting high-field magnet.

(First embodiment)
FIG. 3 is a schematic cross-sectional perspective view of the multilayer superconducting coil device 10 (hereinafter simply referred to as “device 10”) according to the first embodiment.
As shown in FIG. 3, the device 10 according to the first embodiment includes a winding member 12 including a plurality of superconducting coils 11 stacked in the winding axis direction C.
Contact surfaces of adjacent superconducting coils 11 are insulated from each other, and are electrically connected only at the innermost circumference or the outermost circumference of the thin film tape wire 20.

Since the superconducting coil 11 is normally wound along the winding frame 13, it has a circular cavity centered on the winding axis C.
Therefore, the winding member 12 on which the superconducting coil 11 is laminated also has a cylindrical cavity portion 14 with the winding axis C as the center.
The hollow portion 14 is provided with a cylindrical member 35 having a diameter approximately equal to or slightly smaller than the diameter of the hollow portion 14 so as to penetrate the hollow portion 14.
In addition, by making the difference between the diameter of the hollow portion 14 and the diameter of the tubular member 35 within an allowable range of deviation in the normal direction D of the superconducting coil 11, the tubular member 35 is in the normal direction D of the superconducting coil 11. It becomes a stopper for deviation.

A flange 33 having a diameter approximately equal to the diameter of the outermost periphery of the superconducting coil 11 is fixed to the cylindrical member 35.
The flange 33 is fixed so as to face one side or both sides of the end face 32 in the winding axis direction C of the winding member 12.

A pressing member 34 is fixed to at least one of the flanges 33 so as to be movable in the winding axis direction C.
When the flange 33 is provided for both end surfaces 32, the pressing member 34 may be provided on only one of them.
The pressing member 34 is, for example, a bolt or the like provided through the flange 33 as shown in FIG.
The pressing member 34 is pressed against the end surface 32 of the winding member 12 via a dispersion plate 37 that distributes the pressure generated by the pressing.

By using the dispersion plate 37 for the pressing of the pressing member 34, it is possible to prevent the thin film tape wire 20 from being deteriorated due to the pressure being concentrated on a part of the thin film tape wire 20 forming the end face 32.
The pressing member 34 and the dispersion plate 37 may be integrally formed.
The tubular member 35 may be provided with, for example, a ring-shaped stopper 38 that prevents the flange 33 from jumping up due to the repulsive force caused by the pressing of the pressing member 34, by integration or retrofitting.

For the cylindrical member 35, the flange 33, and the dispersion plate 37 described above, for example, a nonmagnetic metal such as copper, aluminum, stainless steel, or brass is preferably used.
In addition, a non-magnetic material such as fiber reinforced plastic or polycarbonate, which has a high insulating property, is also preferably used.

Of the superconducting coils 11 to be laminated, some of the superconducting coils 11 are not bonded or weakly bonded to other superconducting coils 11.
Weak adhesion means that one of the superconducting coils 11 that have been adhered is adhered to such an extent that they can be pulled apart without causing damage that would degrade the superconducting characteristics of the other superconducting coil 11.
For example, when the increasing rate of the resistance value of the superconducting coil 11 after being separated is 1% or less, it can be said that the superconducting characteristic of the superconducting coil 11 is not damaged.

In order to adhere the superconducting coil 11 to weak adhesion, for example, a release agent 42 is bonded or applied to the adhesive surface 41 between the adhesive 39 such as an epoxy resin and the superconducting coil 11 to form the release layer 42.
As the release agent, a fluororesin tape, paraffin, grease, silicone oil, or the like is preferably used.
Hereinafter, in each embodiment, the fact that the superconducting coils 11 are non-adhered or weakly bonded is expressed as “non-adhered” including that they are bonded to weakly bonded.

Such non-adhesive portions are provided in every several superconducting coils 11, for example.
For example, if twelve superconducting coils 11 are stacked and non-adhered portions are provided every three, the winding member 12 can be divided into three blocks composed of four superconducting coils 11.
That is, when the superconducting coil 11 needs to be replaced, if one block is replaced, it is not necessary to replace all of them.
Of course, all superconducting coils 11 may be laminated in a non-adhesive manner.

As described above, when the low-temperature superconducting coil is used, the adjacent low-temperature superconducting coils are firmly bonded in order to prevent the characteristic deterioration due to the shift of the low-temperature superconducting coil.
However, when using a high-temperature superconducting coil, it is necessary to be able to easily replace some high-temperature superconducting coils that are not problematic when using a low-temperature superconducting coil.
Thus, in the apparatus 10 according to the first embodiment, the superconducting coils 11 are not bonded, while the pressing member 34 presses the end surface 32 of the winding member 12 in the winding axis direction C.
The superconducting coil 11 can be prevented from shifting in the winding axis direction C and the direction perpendicular to the winding axis direction C of the superconducting coil 11.

  Further, by making the superconducting coils 11 non-bonded, excessive restraint of the thin film tape wire 20 is avoided, and deterioration of the thin film tape wire 20 due to peeling of each layer (21 to 26) of the thin film tape wire 20 is also avoided. You can also.

  As described above, according to the device 10 according to the first embodiment, it is possible to suppress the deviation of the plurality of stacked superconducting coils 11 from the specified position and easily exchange a part thereof.

(Second Embodiment)
FIG. 4A is a schematic front sectional view of the device 10 according to the second embodiment.
FIG. 4B is a schematic front sectional view showing a modification of the device 10 according to the second embodiment.
4A and 4B are front cross-sectional views at the same position as in FIG. 3 shown in the first embodiment, but only a cross-sectional portion is shown for simplicity. The same applies to the subsequent drawings.

In the apparatus 10 according to the second embodiment, as shown in FIGS. 4A and 4B, the dispersion plate 37 or the pressing member 34 has a spring material 43 such as a coil spring, a thin plate spring, and a disc spring. It is provided and has elasticity in the winding axis direction C.
FIG. 4A shows an example in which the spring material 43 is provided on the dispersion plate 37, and FIG. 4B shows an example in which the spring material 43 is provided on the pressing member 34.

The superconducting coil 11 itself is deformed by thermal contraction or the like regardless of whether or not the pressing member 34 is pressurized.
Therefore, when the pressing member 34 or the dispersion plate 37 is not elastic at all, even if the pressing member 34 is pressed at an optimum pressure at room temperature, it becomes non-contact when the superconducting current is generated.
Therefore, the pressing member 34 or the dispersion plate 37 needs to have a displacement tolerance larger than the sum of the amount of thermal contraction and the amount of displacement of the winding member 12 due to electromagnetic force.

Therefore, as described above, the length, type, number, and the like of the spring member 43 are adjusted to give the dispersion plate 37 a displacement margin that is larger than the total amount of displacement.
By applying pressure with such a highly elastic dispersion plate 37 or pressing member 34, even if there is a non-adhered superconducting coil 11 in the adjacent superconducting coil 11, the displacement of the superconducting coil 11 due to external force is reduced.

In addition, since 2nd Embodiment becomes the same structure as 1st Embodiment except providing sufficient elasticity to the dispersion plate 37 or the pressing member 34, the overlapping description is abbreviate | omitted.
Also in the drawings, portions having a common configuration or function are denoted by the same reference numerals, and redundant description is omitted.

  As described above, according to the second embodiment, even when the adjacent superconducting coils 11 are not bonded, it is possible to reliably pressurize in the winding axis direction C and reduce the deviation of the superconducting coil 11.

(Third embodiment)
FIG. 5A is a schematic front cross-sectional view of the device 10 according to the third embodiment, and FIG. 5B is a top cross-sectional view taken along the line II of the device 10 shown in FIG.
As shown in FIG. 5, the device 10 according to the third embodiment winds a part or all of the superconducting coils 11 to be non-adhered between specific turns 20 _n and 20 _{n + 1} facing each other. .

Usually, the thin film tape line 20 and the first k-th revolution of the turn 20 _k and the k + 1 week of the turn 20 k _{+ 1} that faces wound, is insulated by an insulating material 44 disposed on these gaps.
The method of arranging the insulating material 44 can be roughly divided into the following two, for example.
One is a method of insulating the turns 20 _k (k = 1, 2,..., N,...) By impregnating the superconducting coil 11 with resin after winding the thin film tape wire 20 alone.

The other is a method in which an insulating tape having the same shape as the thin film tape wire 20 is wound on the thin film tape wire 20 while being wound.
Even when an insulating tape is used, the superconducting coil 11 is often fixed by impregnating the resin after the superconducting coil 11 is formed.
In any case, each turn 20 _k is insulated, thereby preventing the superconducting current from being short-circuited in the normal direction D.

The contraction or expansion of the superconducting coil 11 during cooling or the like generates a stress that displaces the relative position of these turns at each of the opposing turns 20 _k .
However, if the opposing turns 20 _k and 20 _{k + 1} are insulated and firmly bonded as applied to the conventional low-temperature superconducting coil, free displacement of the thin film tape wire 20 in accordance with the stress is hindered.
Therefore, the thin film tape wire 20 may be deteriorated by peeling or breaking each layer (21 to 26) of the thin film tape wire 20 that is weak and easily peels off.

Therefore, for some or all of the superconducting coils 11 having a high risk of deterioration, a release layer 42 is formed on the insulating material 44 that is wound and disposed between the opposing turns 20 _n and 20 _{n + 1.} To release the mold.
As described in the first embodiment, since the deformation of the superconducting coil 11 changes the shape of the magnetic field, it is desirable to perform such a separation process between specific turns 20 _n and 20 _{n + 1 of the} entire turn. .

For example, it is possible to perform a release treatment by previously applying the release agent shown in the first embodiment to the thin film tape wire 20.
By this release treatment, when a strong stress is applied to the thin film tape wire 20, the turn _20n is peeled off and can be deformed into a shape that relaxes the stress.
Note that the position of the turn 20 _n to be non-adhered is appropriately determined depending on the position where the superconducting coil 11 is laminated.
For example, depending on the stacking position, all the turns 20 _k of the superconducting coil 11 may be unbonded.

Since the third embodiment has the same structure as that of the first embodiment except that the bonding between the turns 20 _n and 20 _{n + 1 of} the superconducting coil 11 is weakly bonded, the redundant description is omitted.
Also in the drawings, portions having a common configuration or function are denoted by the same reference numerals, and redundant description is omitted.

Thus, according to the device 10 according to the third embodiment, in addition to the effects of the first embodiment, by allowing the displacement of the relative position between some or all of the turns 20 _n and 20 _{n + 1} , It is possible to prevent deterioration of superconducting characteristics due to peeling of the respective layers (21 to 26) constituting the thin film tape wire 20.

(Fourth embodiment)
FIG. 6 is a schematic front sectional view of the device 10 according to the fourth embodiment.

In the apparatus 10 according to the fourth embodiment, as shown in FIG. 6, a cooling foil 45 that transfers cold heat to the superconducting coil 11 is disposed in the gap between the superconducting coils 11 that are stacked and adjacent to each other.
When the adhesive 39 is disposed in the gap, the cooling foil 45 is disposed so as to be embedded in the adhesive 46.

As described above, the device 10 is often housed in a cooler (not shown) and cooled into a superconducting high field magnet.
A refrigerator 47 serving as a cooling heat source for cooling the superconducting coil 11 is installed in the cooler.
One end of a cooling foil 45 that transfers the cold heat of the refrigerator 47 to the superconducting coil 11 is connected to the refrigerator 47.

Conventionally, the other end of the cooling foil 45 is provided on the outer surface of the winding member 12 such as the end surface 32 of the winding member 12.
And the superconducting coil 11 which adjoined from this end surface 32 was transferred in order, and the internal superconducting coil 11 was cooled.
However, when the winding member 12 is cooled only from a part of the outer surface of the winding member 12 in this way, the winding member 12 is not uniform until the superconducting coil 11 in the middle of the winding member 12 is sufficiently cooled. Temperature distribution is possible.
Similarly, such a cooling method generates a non-uniform temperature distribution even within one superconducting coil 11.

Such a temperature distribution causes the stress generated in the superconducting coil 11 to be localized, and causes the stress to deform nonuniformly.
Therefore, in the fourth embodiment, the other end of the cooling foil 45 is inserted into the bonding portion between the superconducting coils 11 to directly cool the superconducting coils 11 in the middle part.

Moreover, the cooling foil 45 is arrange | positioned so that the side surface of the superconducting coil 11 in which the adhesive 39 is arrange | positioned may be coat | covered without lack.
Thus, the cooling foil 45 covers the side surface of the superconducting coil 11 without deficiency, so that the temperature distribution generated in the same superconducting coil 11 is maintained to be uniform and cooled.

In addition, it is preferable to use the cooling foil 45 having a higher thermal conductivity than the superconducting coil 11 so that the temperature distribution does not occur in the cooling foil 45 itself.
In addition, insulation treatment such as coating the cooling foil 45 is performed as necessary so that the cooling foil 45 is not electrically connected to the superconducting coil 11 and the superconducting current is short-circuited.

Since the fourth embodiment has the same structure as that of the first embodiment except that the cooling foil 45 is inserted between the adjacent superconducting coils 11, a duplicate description is omitted.
Also in the drawings, portions having a common configuration or function are denoted by the same reference numerals, and redundant description is omitted.

  As described above, according to the device 10 according to the fourth embodiment, in addition to the effects of the first embodiment, it is possible to prevent the stress caused by the non-uniform temperature distribution during the cooling and the deformation due to the stress from occurring. Can do.

  According to the apparatus 10 of at least one embodiment described above, it is possible to suppress the deviation of the plurality of stacked superconducting coils 11 from the specified position and to easily replace a part thereof.

Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention.
These embodiments can be implemented in various other forms, and various omissions, replacements, changes, and combinations can be made without departing from the scope of the invention.
These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

For example, FIG. 7A is a schematic perspective view of the double pancake coil 51.
The double pancake coil 51 is a coil integrated by stacking two stages of superconducting coils 11 in which thin film tape wires 20 are concentrically wound and electrically connecting the innermost circumference.
FIG. 7B is a schematic perspective view of the solenoid coil 52.
The solenoid coil 52 is a coil formed by winding one thin film tape wire 20 while shifting in the winding axis direction C, and repeating this winding and folding at the end.
The superconducting coil 11 to be laminated may be a double pancake coil 51 or a solenoid coil 52.

Further, FIG. 7C is a schematic top view of the racetrack coil 53.
The racetrack type coil 53 is a coil obtained by winding the thin film tape wire 20 concentrically without shifting in the winding axis direction C, like the superconducting coil 11 described above.
The racetrack type coil 53 is entirely formed into a racetrack shape by being wound around a racetrack-shaped winding frame 13.
The superconducting coil 11 to be laminated may be such a racetrack type coil 53.

DESCRIPTION OF SYMBOLS 10 ... Laminated superconducting coil apparatus (apparatus), 11 ... High temperature superconducting coil (superconducting coil), 12 ... Winding member, 13 ... Winding frame, 14 ... Cavity, 20 { _20k ( _20n )} ... Thin film tape wire (High-temperature superconducting wire) {turn (non-adhesive turn)}, 21 ... stabilization layer, 22 ... substrate, 23 ... alignment layer, 24 ... intermediate layer, 25 ... oxide superconducting layer, 26 ... protective layer, 32 ... end face 33 ... Flange 34 ... Pressing member 35 ... Cylinder material 37 ... Distributing plate 38 ... Stopper 39 ... Adhesive material 41 ... Adhesive surface (contact surface) 42 ... Releasing layer 43 ... Spring material 44 ... insulating material, 45 ... cooling foil, 46 ... adhesive, 47 ... refrigerator, C ... winding axis (winding axis direction), D ... normal direction.

Claims (9)

A winding member in which a plurality of superconducting coils formed by winding a high-temperature superconducting wire are laminated in the winding axis direction;
A cylindrical material that is disposed along the innermost circumferential surface of the superconducting coil and penetrates the winding member in the winding axis direction; and
A flange fixed to the cylindrical member so as to face at least one of the end surfaces of the winding member in the winding axis direction;
A pressing member fixed to the flange movably in the winding axis direction and pressed against the end face;
A dispersion plate that is provided on the end surface and disperses the pressure applied to the end surface by the pressing member;
The dispersion plate includes at least one spring material selected from the group consisting of a coil spring, a thin plate spring, and a disc spring,
A laminated superconducting coil device characterized in that at least a part of a contact surface in contact with another adjacent high-temperature superconducting coil of the superconducting coil to be laminated is made non-adhesive or weakly bonded by a release process. The multilayer superconducting coil device according to claim 1, wherein the pressing member is a bolt provided through the flange. The pressing displacement during pressing member Te is according to claim 1 or claim 2 greater than the sum of the winding axis direction of the displacement due to thermal shrinkage amount and the electromagnetic force generated by the cooling of the winding member Multilayer superconducting coil device. The multilayer superconducting coil device according to any one of claims 1 to 3 , wherein the cylindrical member is provided in contact with the innermost peripheral surface. The multilayer superconducting coil device according to any one of claims 1 to 4 , wherein the releasing treatment is formation of a releasing layer on an adhesive surface of the adhesive with the superconducting coil. The laminated superconducting coil according to any one of claims 1 to 5 , wherein at least one of the superconducting coils is wound and the release treatment is performed on an insulating material disposed between opposing turns. apparatus. The multilayer superconducting coil device according to claim 6 , wherein the release treatment is adhesion or application of at least one release agent selected from the group consisting of fluororesin tape, paraffin, grease and silicone oil. The laminated superconducting coil device according to any one of claims 1 to 7 , wherein a cooling foil that transfers cold heat to the superconducting coils is disposed in a gap between the adjacent superconducting coils. The stacked superconducting coil device according to claim 8 , wherein the cooling foil has higher thermal conductivity than the superconducting coil.

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