Superconducting coil

Abstract

A superconducting coil (10) comprises a winding frame (12), a coil body (14) that comprises a plurality of layers of superconducting wire (15) that are layered on the winding frame (12), each layer of the coil body (14) having a plurality of turns of the superconducting wire (15), a first fixation wall (16) that is provided to the winding frame (12) so as to be adjacent to a first turn (14a_1) of the plurality of turns of at least a first layer (14a) of the plurality of layers, and a first impregnation material (20) that contains a photocurable resin material and impregnates at least a portion of the space between the first turn (14a_1) and the first fixation wall (16).

Description

superconducting coil

[0001] The present invention relates to a superconducting coil.

[0002] A superconducting coil is formed by winding a superconducting wire. The wound superconducting wire is impregnated with a synthetic resin material to fix the superconducting wire and to improve the mechanical strength of the superconducting coil.

[0003] Japanese Patent Application Publication No. 4-91407

[0004] Generally, a thermosetting resin is used to impregnate the wound superconducting wire. The thermosetting process can take, for example, several hours to several tens of hours or more. Therefore, the manufacturing of a superconducting coil takes a long time.

[0005] An exemplary object of certain aspects of the present invention is to improve workability in the manufacture of superconducting coils.

[0006] According to one aspect of the present invention, a superconducting coil includes a reel, a coil body including multiple layers of superconducting wire stacked on the reel, each layer having multiple turns of the superconducting wire, a first fixed wall provided on the reel so as to be adjacent to a start turn of the multiple turns in at least a first layer of the multiple layers, and a first impregnating material containing a photocurable resin material and impregnating at least a portion between the start turn and the first fixed wall.

[0007] According to the present invention, the workability in manufacturing a superconducting coil can be improved.

[0008] 3(a) and 3(b) are diagrams schematically showing a superconducting coil according to an embodiment, a manufacturing process for a superconducting coil according to an embodiment, and a comparative example.

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the description and drawings, identical or equivalent components, parts, and processes are designated by the same reference numerals, and redundant explanations will be omitted as appropriate. The scale and shape of each part shown in the drawings are set for convenience to facilitate explanation, and should not be interpreted as limiting unless otherwise specified. The embodiments are merely examples and do not limit the scope of the present invention in any way. All features and combinations thereof described in the embodiments are not necessarily essential to the invention.

[0010] Fig. 1 is a diagram schematically showing a superconducting coil 10 according to an embodiment of the present invention, in which a cross section of the superconducting coil 10 taken along a plane including a center line C of the superconducting coil 10 is shown.

[0011] The superconducting coil 10 is configured to generate a strong magnetic field when current is applied while the coil is cooled to an extremely low temperature below the superconducting transition temperature. The superconducting coil 10 may be a known superconducting coil, for example, a low-temperature superconducting coil. Alternatively, the superconducting coil 10 may be a high-temperature superconducting coil. The superconducting coil 10 is installed in high-magnetic field equipment (not shown), for example, as a magnetic field source for accelerators such as NMR systems, MRI systems, cyclotrons, high-energy physics systems such as nuclear fusion systems, or other high-magnetic field equipment, and can generate the high magnetic field required for the equipment.

[0012] The superconducting coil 10 includes a bobbin 12 , a coil body 14 , a first fixed wall 16 , and a second fixed wall 18 .

[0013] The bobbin 12 supports the coil body 14. The bobbin 12 may be made of a non-magnetic metal material such as stainless steel or an aluminum alloy. Alternatively, the bobbin 12 may be made of a fiber-reinforced plastic (FRP) such as glass fiber-reinforced plastic (GFRP), or any other suitable material.

[0014] The reel 12 has an annular winding surface 13. The winding surface 13 is formed on the reel 12 along an imaginary plane that intersects with the center line C. For example, the winding surface 13 may be formed on the reel 12 along a plane perpendicular to the center line C. The winding surface 13 may be formed on the reel 12 along a curved surface that intersects with the center line C. The center line C may be parallel to the direction of gravity, that is, the vertical direction, and the upper surface of the reel 12 may be used as the winding surface 13. When viewed from the direction of the center line C, the winding surface 13 may have various planar shapes, such as a circle, an oval such as a racetrack shape, or a rectangle.

[0015] The coil body 14 is formed by winding a superconducting wire 15. The coil body 14 includes a plurality of layers of the superconducting wire 15 stacked on the bobbin 12. Each layer has a plurality of turns of the superconducting wire 15.

[0016] As an example, the coil body 14 may be a so-called multi-layer pancake coil. In this case, the multiple turns in each layer are wound in a spiral shape around the center line C. In other words, the multiple turns in each layer are wound around the center line C so that the distance from the center line C to each turn varies. The coil body 14 may have a cylindrical shape. Alternatively, the coil body 14 may have a saddle-shaped shape.

[0017] In the illustrated example, the coil body 14 has a first layer 14a and a second layer 14b. The first layer 14a of the coil body 14 is laminated on the winding surface 13 of the bobbin 12. The second layer 14b of the coil body 14 is laminated on the first layer 14a.

[0018] The first layer 14a has the first turn 14a_1 to the n-th turn 14a_n (where n can be any natural number greater than 1). The first turn 14a_1 is the first turn of the first layer 14a, and the n-th turn 14a_n is the last turn of the first layer 14a. In this example, the first layer 14a is wound around the center line C along the winding surface 13 so that the first turn 14a_1 is located on the outer periphery of the coil body 14 (i.e., the side farther from the center line C) and the n-th turn 14a_n is located on the inner periphery of the coil body 14 (i.e., the side closer to the center line C). Note that the winding method may be reversed, and the first layer 14a may be wound around the center line C so that the first turn 14a_1 is located on the inner periphery and the n-th turn 14a_n is located on the outer periphery.

[0019] The second layer 14b has a first turn 14b_1 at the start of winding to an n-th turn 14b_n at the end of winding. In this example, the second layer 14b is wound around the center line C along the winding surface 13 in the opposite direction to the first layer 14a, with the first turn 14b_1 located on the inner periphery of the coil body 14 and the n-th turn 14a_n located on the outer periphery of the coil body 14. Therefore, the first turn 14b_1 of the second layer 14b is located above the n-th turn 14a_n of the first layer 14a. In another example, the second layer 14b may be wound such that the first turn 14b_1 of the second layer 14b is located above the first turn 14a_1 of the first layer 14a.

[0020] For simplicity, the coil body 14 has been described as having two layers, a first layer 14a and a second layer 14b, but the coil body 14 may have at least one additional layer laminated on the second layer 14b. The coil body 14 may have at least 10 layers (e.g., several tens of layers). Furthermore, one layer of the coil body 14 may have at least 10 turns (e.g., several tens of turns).

[0021] The superconducting wire 15 may be a non-tape-shaped superconducting wire. For example, the superconducting wire 15 may be a round wire or a rectangular wire (e.g., a rectangular wire). The superconducting wire 15 includes a superconductor. When the superconducting coil 10 is a low-temperature superconducting coil, the superconducting wire 15 may include a superconductor formed of a superconducting material such as a niobium-titanium alloy (NbTi) or a niobium-tin alloy (NbSn). When the superconducting coil 10 is a high-temperature superconducting coil, the superconducting wire 15 may include a superconductor formed of, for example, magnesium diboride, a bismuth-based superconductor, a copper oxide superconductor, or another high-temperature superconducting material.

[0022] The first fixed wall 16 is provided on the winding frame 12 so as to be adjacent to the initial turn (first turn 14a_1) of the multiple turns in at least the first layer 14a of the multiple layers of the coil body 14. In this example, the first turn 14a_1 of the first layer 14a is located on the outer periphery of the coil body 14, and therefore the first fixed wall 16 is adjacent to the outer periphery of the coil body 14.

[0023] The first fixed wall 16 extends upward from the bobbin 12 in the stacking direction of the coil body 14 (i.e., the direction of the center line C), and is also adjacent to the second layer 14 b. In this example, the final turn of the second layer 14 b (the n-th turn 14 b_n) is located above the first turn 14 a_1 of the first layer 14 a, and therefore the first fixed wall 16 is adjacent to the n-th turn 14 b_n of the second layer 14 b.

[0024] In this embodiment, the first fixing wall 16 has a structure divided into sections for each layer of the coil body 14. The first fixing wall 16 includes a first wall member 16a adjacent to the first layer 14a of the coil body 14, and a second wall member 16b attached to the first wall member 16a and adjacent to the second layer 14b of the coil body 14.

[0025] The height of each wall material (e.g., first wall material 16a or second wall material 16b) constituting first fixed wall 16 corresponds to the height of superconducting wire 15. For example, the height of each wall material may be equal to or greater than the height of superconducting wire 15. The height of each wall material may be 1.1 times or less the height of superconducting wire 15. Here, the height of a wall material refers to the dimension of the wall material in the direction of center line C. The height of superconducting wire 15 refers to the dimension of superconducting wire 15 in the direction of center line C, for example, the diameter of superconducting wire 15.

[0026] The second fixed wall 18 is provided on the winding frame 12 so as to be adjacent to the final turn (the n-th turn 14a_n) of the multiple turns in the first layer 14a of the coil body 14. In this example, the n-th turn 14a_n of the first layer 14a is located on the inner circumferential side of the coil body 14, and therefore the first fixed wall 16 is adjacent to the inner circumferential side of the coil body 14.

[0027] The second fixed wall 18 extends upward from the bobbin 12 in the stacking direction of the coil body 14 (i.e., the direction of the center line C) and is also adjacent to the second layer 14b. In this example, the first turn (first turn 14b_1) of the second layer 14b is located above the n-th turn 14a_n of the first layer 14a, and therefore the second fixed wall 18 is adjacent to the first turn 14b_1 of the second layer 14b. Note that, as described above, the last turn (n-th turn 14b_n) of the second layer 14b may be located above the n-th turn 14a_n of the first layer 14a, in which case the second fixed wall 18 may be adjacent to the n-th turn 14b_n of the second layer 14b.

[0028] Similar to the first fixed wall 16, the second fixed wall 18 has a structure divided into sections for each layer of the coil body 14. The second fixed wall 18 includes a first wall material 18a adjacent to the first layer 14a of the coil body 14, and a second wall material 18b attached to the first wall material 18a and adjacent to the second layer 14b of the coil body 14.

[0029] The height of each wall material (e.g., first wall material 18a or second wall material 18b) constituting second fixed wall 18 corresponds to the height of superconducting wire 15. For example, the height of each wall material may be equal to or greater than the height of superconducting wire 15. The height of each wall material may be 1.1 times or less the height of superconducting wire 15. Furthermore, the height of each wall material constituting second fixed wall 18 may be equal to the height of each wall material constituting first fixed wall 16.

[0030] When the coil body 14 has at least one additional layer laminated to the second layer 14b, the first fixed wall 16 may include at least one additional wall material attached to the second wall material 16b. Similarly, the second fixed wall 18 may include at least one additional wall material attached to the second wall material 18b. Each of the at least one additional wall material may be adjacent to a corresponding one of the at least one additional layers of the coil body 14.

[0031] The first fixed wall 16 may be provided on the winding frame 12 so as to be adjacent to the coil body 14 around the center line C over the entire circumference of the coil body 14. In this case, the first fixed wall 16 may be continuous along the circumference of the coil body 14. Alternatively, the first fixed wall 16 may be divided along the circumference of the coil body 14. For example, the first fixed wall 16 may include a plurality of wall pieces each adjacent to the coil body 14, and these wall pieces may be arranged without gaps along the circumference of the coil body 14. Similarly, the second fixed wall 18 may be provided on the winding frame 12 so as to be adjacent to the coil body 14 over the entire circumference of the coil body 14 around the center line C.

[0032] Alternatively, the first fixed wall 16 may be provided on the bobbin 12 so as to be adjacent to the coil body 14 along a portion of the entire circumference of the coil body 14. For example, the first fixed wall 16 may include a plurality of wall pieces, each of which is adjacent to the coil body 14, and these wall pieces may be arranged at intervals (e.g., equal intervals) from one another along the circumference of the coil body 14. Similarly, the second fixed wall 18 may be provided on the bobbin 12 so as to be adjacent to the coil body 14 along a portion of the entire circumference of the coil body 14.

[0033] The first fixed wall 16 and the second fixed wall 18 may be formed of the same material as the reel 12, or may be formed of a material different from that of the reel 12. Thus, the fixed walls may be formed of a non-magnetic metal material such as stainless steel or an aluminum alloy. Alternatively, the fixed walls may be formed of a fiber reinforced plastic (FRP) such as glass fiber reinforced plastic (GFRP), or any other suitable material.

[0034] The first fixed wall 16 and the second fixed wall 18 may be mechanically fixed to the reel 12 using fastening members such as bolts or screws. Alternatively, the first fixed wall 16 and the second fixed wall 18 may be fixed to the reel 12 by adhesive or any other appropriate method. Furthermore, the wall materials constituting the fixed walls may also be fixed to each other mechanically or by any other appropriate method.

[0035] The coil body 14 also includes a first impregnation material 20 , a second impregnation material 22 , and a sheet material 24 .

[0036] The first impregnating material 20 contains a photocurable resin material, and in this example, is made of a photocurable resin material. The photocurable resin material may be a known UV-curable resin material, such as an acrylic UV-curable resin material or an epoxy UV-curable resin material. Alternatively, the photocurable resin material may be a visible light-curable resin material.

[0037] The first impregnating material 20 is impregnated into at least a portion of the space between the coil body 14 and the first fixing wall 16. In the illustrated example, the first impregnating material 20 is impregnated into at least a portion of the space between the first turn 14a_1 of the first layer 14a and the first fixing wall 16, and at least a portion of the space between the n-th turn 14b_n of the second layer 14b and the first fixing wall 16. The first impregnating material 20 may be impregnated over the entire circumference of the coil body 14 along the first fixing wall 16, or may be impregnated into a portion (or multiple portions) of the entire circumference of the coil body 14 along the first fixing wall 16. In this manner, the coil body 14 is fixed to the first fixing wall 16 by the first impregnating material 20.

[0038] The first impregnation material 20 also permeates at least a portion of the space between the coil body 14 and the second fixing wall 18. In the illustrated example, the first impregnation material 20 permeates at least a portion of the space between the n-th turn 14a_n of the first layer 14a and the second fixing wall 18, and at least a portion of the space between the first turn 14b_1 of the second layer 14b and the second fixing wall 18. The first impregnation material 20 may be permeated over the entire circumference of the coil body 14 along the second fixing wall 18, or may be permeated into a portion (or multiple portions) of the entire circumference of the coil body 14 along the second fixing wall 18. In this manner, the coil body 14 is fixed to the second fixing wall 18 by the first impregnation material 20.

[0039] The first impregnating material 20 also permeates at least a portion of the space between the first layer 14a of the coil body 14 and the winding surface 13 of the bobbin 12. In this way, the coil body 14 is fixed to the bobbin 12 by the first impregnating material 20. Furthermore, in order to fix the first layer 14a and the second layer 14b of the coil body 14, the first impregnating material 20 also permeates at least a portion of the space between the first layer 14a and the second layer 14b of the coil body 14. In the illustrated example, a sheet material 24 is provided between the first layer 14a and the second layer 14b, and therefore the first impregnating material 20 permeates at least a portion of the space between the sheet material 24 and the second layer 14b.

[0040] The second impregnating material 22 is impregnated between two adjacent layers of the multiple layers of the coil body 14. The second impregnating material 22 is impregnated into at least a portion of the space between the first layer 14a and the second layer 14b of the coil body 14. In the illustrated example, a sheet material 24 is provided between the first layer 14a and the second layer 14b, so the second impregnating material 22 is impregnated into at least a portion of the space between the first layer 14a and the sheet material 24. The second impregnating material 22 may be, for example, a thermosetting resin material, an adhesive, or any other appropriate synthetic resin material. In this way, the two adjacent layers of the coil body 14 are fixed to each other by the second impregnating material 22.

[0041] The sheet material 24 is provided between two adjacent layers of the multiple layers of the coil body 14 so as to separate the two layers. The sheet material 24 may be formed, for example, of fiber-reinforced plastic (FRP) such as glass fiber-reinforced plastic (GFRP), or other suitable insulating material. As shown in the figure, when the first fixing wall 16 and the second fixing wall 18 have a divided structure, the sheet material 24 may be sandwiched between two stacked wall materials (e.g., the first wall material 16a and the second wall material 16b).

[0042] 2 is a diagram schematically showing a manufacturing process of the superconducting coil 10 according to the embodiment. In this manufacturing process, first, as shown in S10 in FIG. 2, the bobbin 12 is prepared, and the first wall material 16a of the first fixed wall 16 is placed on the bobbin 12. The first turn 14a_1 of the first layer 14a of the coil body 14 is wound onto the winding surface 13 of the bobbin 12 so as to be adjacent to the first wall material 16a. The first impregnation material 20 is applied between the first turn 14a_1 of the first layer 14a and the first wall material 16a.

[0043] Then, a light source 30 is prepared that can emit light 32 that cures the photocurable resin material contained in the first impregnating material 20. The light source 30 is positioned above the first wall material 16a and the first turn 14a_1 of the first layer 14a so as to irradiate the light 32 perpendicularly toward the winding surface 13. The light 32 is irradiated downward from the light source 30 toward the first wall material 16a and the first turn 14a_1. This cures the first impregnating material 20 between the first wall material 16a and the first turn 14a_1.

[0044] 2, the first layer 14a of the coil body 14 is wound up to the n-th turn 14a_n. The first wall material 18a of the second fixed wall 18 is placed on the bobbin 12 adjacent to the n-th turn 14a_n. Note that the first wall material 18a of the second fixed wall 18 may be placed on the bobbin 12 in advance (together with the first wall material 16a of the first fixed wall 16, for example) before the n-th turn 14a_n is wound. The first impregnation material 20 is applied to each turn of the first layer 14a.

[0045] As shown by the dashed arrow in S11 of FIG. 2 , the light source 30 moves above the first layer 14a, irradiating the n-th turn 14a_n with light 32 in order. The light source 30 irradiates each turn with light 32 in the same direction. That is, the light source 30 irradiates each turn of the first layer 14a with light 32 vertically from above. The irradiation of light 32 hardens the first impregnating material 20 between the first layer 14a and the winding surface 13. The first impregnating material 20 also hardens between the first wall material 18a of the second fixed wall 18 and the n-th turn 14a_n. In this way, the first layer 14a is fixed to the reel 12, the first fixed wall 16, and the second fixed wall 18.

[0046] 2, a second impregnating material 22 is applied onto the first layer 14a so as to cover the first layer 14a. The second impregnating material 22 is applied to the same height as the first wall material 16a of the first fixed wall 16 and the first wall material 18a of the second fixed wall 18. Then, a sheet material 24 is laid on the second impregnating material 22 and these fixed walls. As the second impregnating material 22 hardens, the first layer 14a is completely fixed to the reel 12 and the fixed walls.

[0047] Next, as shown in S20 of FIG. 2 , the second wall material 18b of the second fixing wall 18 is installed on the first wall material 18a. A sheet material 24 is sandwiched between the first wall material 18a and the second wall material 18b. The first turn 14b_1 of the second layer 14b of the coil body 14 is wound on the first layer 14a so as to be adjacent to the second wall material 18b. A first impregnating material 20 is applied between the first turn 14b_1 of the second layer 14b and the second wall material 18b. Then, the light source 30 irradiates light 32 vertically from above the first turn 14b_1 of the second layer 14b. This hardens the first impregnating material 20 between the second wall material 18b and the first turn 14b_1.

[0048] Next, as shown in S21 of FIG. 2 , the second layer 14b of the coil body 14 is wound up to the nth turn 14b_n. The second wall material 16b of the first fixed wall 16 is placed on the first wall material 16a adjacent to the nth turn 14b_n. The sheet material 24 is sandwiched between the first wall material 16a and the second wall material 16b. The first impregnating material 20 is applied to each turn of the first layer 14a. As schematically indicated by the dashed arrow, the light source 30 moves above the second layer 14b and irradiates light 32 sequentially up to the nth turn 14b_n. The light source 30 irradiates each turn with light 32 in the same direction. That is, the light source 30 irradiates light 32 vertically from above each turn of the second layer 14b. The irradiation of light 32 hardens the first impregnating material 20 between the second layer 14a and the sheet material 24. The first impregnating material 20 is hardened between the second wall material 16b of the first fixing wall 16 and the n-th turn 14b_n. In this way, the second layer 14b is fixed to the first layer 14a, the first fixing wall 16, and the second fixing wall 18.

[0049] A second impregnating material 22 may be applied to the second layer 14b, and a sheet material 24 may be laid on top of that. If the coil body 14 has additional layers, multiple layers can be stacked by repeating the steps S10 to S12 described above.

[0050] As mentioned at the beginning of this book, existing superconducting coils generally use thermosetting resins as impregnation materials. The thermosetting process can take, for example, several hours to several tens of hours or longer, making the manufacture of superconducting coils long. In particular, in the impregnation method, also known as "paint winding," in which the resin material is applied while the superconducting wire is being wound around a bobbin, a thermosetting resin with a relatively long curing time is sometimes intentionally used to prevent the thermal curing of the resin material from interfering with the winding of the superconducting wire around the bobbin. In this case, the thermosetting process takes even longer.

[0051] In contrast, in the superconducting coil 10 according to the embodiment, a photocurable resin material is used as the first impregnating material 20. Photocurable resin materials typically require a photocuring process that takes at most a few minutes. By using the first impregnating material 20, the superconducting wire 15 can be quickly fixed. Furthermore, the second impregnating material 22 that is applied after the wire 15 has been fixed in this manner can be one that has a relatively short curing time. Therefore, the manufacturing time for the superconducting coil 10 according to the embodiment can be dramatically reduced compared to that for existing superconducting coils.

[0052] Moreover, it is easy to selectively apply the light 32 to a local region of the coil body 14. It is also easy to apply the light 32 at any timing while the superconducting wire 15 is being wound around the bobbin 12. In contrast, the thermal curing process has a small degree of freedom in this regard.

[0053] The photocuring process offers a high degree of freedom in determining the irradiation location and timing, making it suitable for manufacturing coils with more complex shapes, such as saddle-shaped coils. Unlike circular coils, coils with complex shapes can present manufacturing challenges, such as the tension acting on the wire during the process of winding the wire around the bobbin causing the wire to shift, making it difficult to maintain the desired coil shape. However, according to the embodiment, by hardening the first impregnation material 20 at a specific location at a desired timing during the wire winding process, the wire can be temporarily fixed in place during the winding, allowing the wire to be wound while maintaining the desired coil shape. Therefore, the superconducting coil 10 according to the embodiment is advantageous for winding coils with complex shapes.

[0054] 3(a) and 3(b) are diagrams schematically illustrating a part of a manufacturing process for a superconducting coil according to a comparative example. In this comparative example, no fixed wall is provided on the bobbin 112. In this case, the inventors noticed that the hardening conditions for the first impregnation material 120 differ between the first turn of the superconducting wire 115 and the second and subsequent turns.

[0055] In the comparative example, in order to fix the first turn of the superconducting wire 115 to the bobbin 112 below it, it is necessary to harden the first impregnating material 120 applied between the first turn of the superconducting wire 115 and the bobbin (i.e., below the first turn). When light 132 from the light source 130 is irradiated vertically from above, a portion 134 of the first impregnating material 120 that is shaded by the first turn is generated below the first turn, as schematically shown by the black portion in FIG. 3( a). This portion 134 of the first impregnating material 120 is less likely to be hit by the light 132, and therefore the first impregnating material 120 is less likely to harden. In other words, the first impregnating material 120 may not adequately bond the first turn to the bobbin 112.

[0056] One way to address this problem is to change the irradiation direction of the light source 130, as shown schematically by the dashed line in Figure 3(a) . By irradiating the first turn with light 132 from the light source 130 at an angle rather than perpendicularly, the light 132 can be made to reach a lower portion 134 of the first turn effectively, thereby effectively curing the first impregnating material 120 in this portion 134.

[0057] However, such oblique irradiation is hardly effective for bonding the second turn and beyond. The second turn is adjacent to the first turn. Therefore, with oblique irradiation, it is difficult for the light to reach the first impregnation material 120 between the adjacent turns. This, in turn, can result in insufficient bonding of the second turn.

[0058] To avoid this, it is considered desirable to change the irradiation direction again from the second turn onwards and irradiate the light 132 vertically from above. This allows the light 132 to reach the first impregnating material 120 between adjacent turns effectively, thereby effectively curing the first impregnating material 120. Furthermore, it is considered desirable to irradiate the nth turn at the end of the winding and the first turn above it from an oblique direction opposite to that of the first turn, as shown in Figure 3(b). However, changing the irradiation direction from the light source 130 for each turn in this way complicates the irradiation work, which is a concern as it reduces workability.

[0059] In contrast, according to the embodiment, the first fixing wall 16 is provided adjacent to the first turn 14a_1 of the first layer 14a. The first fixing wall 16 can be considered a wall that simulates the superconducting wire 15. When light 32 is irradiated perpendicularly from the light source 30 onto each turn, the positional relationship between the light source 30 and the first impregnating material 20 between the first turn 14a_1 and the first fixing wall 16 is the same as the positional relationship between the light source 30 and the first impregnating material 20 between the first turn 14a_1 and the adjacent second turn. The curing conditions for the first turn 14a_1 and the first fixing wall 16 can be made the same as the curing conditions for the first turn 14a_1 and the second turn. This improves adhesion of the first turn 14a_1 and makes the adhesion between the first turn 14a_1 and the other turns uniform.

[0060] Furthermore, according to the embodiment, the second fixing wall 18 is provided adjacent to the n-th turn 14a_n of the first layer 14a. For the same reason, the adhesion of the n-th turn 14a_n can be improved and the adhesion between the n-th turn 14a_n and the other turns can be made uniform. The first fixing wall 16 and the second fixing wall 18 also make the adhesion between each turn of the second layer 14b and subsequent layers uniform.

[0061] In order to manufacture the superconducting coil 10 according to design, it is desirable that the second impregnating material 22 be applied so as to form a flat surface as a base for the layers to be stacked thereon. When there is no fixed wall, as in the comparative example, the flatness of the second impregnating material 22 depends on the skill of the worker, and variations may occur.

[0062] In contrast, according to the embodiment, the second impregnating material 22 can be applied to match the height of the first fixed wall 16 and the second fixed wall 18. If these fixed walls are divided into layers of the coil body 14, for example, for the first layer 14a, the second impregnating material 22 is applied to match the height of the first wall material 16a of the first fixed wall 16 and the first wall material 18a of the second fixed wall 18. Therefore, the second impregnating material 22 can be easily applied evenly regardless of the skill of the worker. In addition, a sheet material 24 is laid on the flattened second impregnating material 22, and the next layer of the coil body 14 is formed on top of that. This also helps to flatten the next layer. Therefore, according to the embodiment, the workability in manufacturing the superconducting coil 10 can be improved.

[0063] The present invention has been described above based on examples. It will be understood by those skilled in the art that the present invention is not limited to the above-described embodiments, and that various design changes and modifications are possible, and that such modifications are also within the scope of the present invention. Various features described in relation to one embodiment can also be applied to other embodiments. A new embodiment created by combining embodiments will have the combined effects of the respective combined embodiments.

[0064] The coil body 14 of the superconducting coil 10 can have various shapes. For example, the coil body 14 may be a cylindrical coil body formed by aligned multilayer winding. In this case, the bobbin 12 may have a cylindrical winding surface 13 centered on the center line C.

[0065] In the above embodiment, the first fixed wall 16 and the second fixed wall 18 are prepared as separate components and attached to the reel 12, but the present invention is not limited to this. The first fixed wall 16 (and / or the second fixed wall 18) may be integral with the reel 12.

[0066] In the above embodiment, the first impregnating material 20 is made of a photocurable resin material, but the first impregnating material 20 may contain other materials in addition to the photocurable resin material. For example, the first impregnating material 20 may be a mixture of a photocurable resin material and another synthetic resin material, such as a thermosetting resin material or a thermoplastic resin material. In this case, the first impregnating material 20 may be cured by using both light irradiation and heat on the coil body 14.

[0067] The second impregnating material 22 may contain a photocurable resin material. The second impregnating material 22 may be made of the same material as the first impregnating material 20.

[0068] The present invention has been described using specific terms based on the embodiments, but the embodiments merely illustrate one aspect of the principles and applications of the present invention, and many modifications and changes in arrangement are permitted to the embodiments as long as they do not deviate from the concept of the present invention as defined in the claims.

[0069] The present invention can be used in the field of superconducting coils.

[0070] 10 Superconducting coil, 12 Winding frame, 14 Coil body, 14a First layer, 14b Second layer, 15 Superconducting wire, 16 First fixed wall, 16a First wall material, 16b Second wall material, 18 Second fixed wall, 18a First wall material, 18b Second wall material, 20 First impregnated material, 22 Second impregnated material, 24 Sheet material.

Claims

1. A superconducting coil comprising: a bobbin; a coil body having a plurality of layers of superconducting wire laminated on the bobbin, each layer having a plurality of turns of the superconducting wire; a first fixed wall provided on the bobbin so as to be adjacent to a start turn of the plurality of turns in at least a first layer of the plurality of layers; and a first impregnating material containing a photocurable resin material and impregnating at least a portion of the space between the start turn and the first fixed wall.

2. A superconducting coil as claimed in claim 1, characterized in that the first fixed wall is also adjacent to a second layer of the plurality of layers that is stacked on the first layer, and the first impregnation material is impregnated into at least a portion of the space between the second layer and the first fixed wall.

3. A superconducting coil as claimed in claim 2, characterized in that the first fixed wall comprises a first wall material adjacent to the first layer and a second wall material attached to the first wall material and adjacent to the second layer.

4. A superconducting coil according to claim 1, wherein said coil body comprises a sheet material between two adjacent layers of said plurality of layers.

5. A superconducting coil according to claim 4, wherein said sheet material is laid on top of a second impregnating material impregnated between said two adjacent layers.

6. The superconducting coil according to claim 1, wherein said coil body comprises a second impregnating material between two adjacent layers of said plurality of layers.

7. A superconducting coil as claimed in claim 6, characterized in that the second impregnating material forms a flat surface on which the upper layer of the two adjacent layers is laminated on the lower layer of the two adjacent layers.

8. A superconducting coil as described in any one of claims 1 to 7, further comprising a second fixed wall provided on the bobbin adjacent to the final turn of the plurality of turns in the first layer, and wherein the first impregnation material is impregnated into at least a portion of the space between the final turn and the second fixed wall.

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