JP7039423B2 - Superconducting magnet device - Google Patents

Description

The present invention relates to a superconducting magnet device that generates a strong magnetic field by passing a large current through a superconducting coil.

A superconducting magnet device that generates a very large electromagnetic force by supplying electric power to a superconducting coil has been developed. As a conventional superconducting magnet device provided with a superconducting coil, the one described in Patent Document 1 is known.

This superconducting magnet device has a pair of superconducting coils and a pair of refrigerators for cooling each of these superconducting coils. The pair of superconducting coils are arranged so as to face each other at positions separated from each other in the axial direction of these superconducting coils. As a result of each pair of superconducting coils being cooled by the pair of refrigerators, a superconducting state is reached, and a large current can flow through these superconducting coils. When a large current flows through these superconducting coils, a strong electromagnetic force is generated between these superconducting coils that acts to attract the pair of superconducting coils to each other.

Japanese Unexamined Patent Publication No. 60-36391

In order to keep the distance between the pair of superconducting coils against the above-mentioned electromagnetic force, a support for supporting these superconducting coils is required. This support needs to have high rigidity. On the other hand, in order to efficiently cool the pair of superconducting coils, a short heat transfer path from these superconducting coils to the pair of refrigerators is required.

It is an object of the present invention to provide a superconducting magnet device that supports a superconducting coil under high mechanical strength and transfers the heat of the superconducting coil to a refrigerator using a short heat transfer path.

The superconducting magnet devices according to one aspect of the present invention are arranged so as to face each other at positions separated from each other in the axial direction, and generate electromagnetic forces acting in directions of attracting each other, respectively, the first superconducting coil and the second superconducting coil. A conduction coil, a frame structure formed to support the first superconducting coil and the second superconducting coil, and a heat transfer portion formed to transfer the heat of the first superconducting coil. It is provided with a refrigerator thermally connected to the heat transfer unit. The frame structure is aligned with the end face of the first superconducting coil in the axial direction so that the plate thickness direction coincides with the axial direction, and the mounting plate to which the first superconducting coil is attached via the heat transfer portion. A first support having a portion and a protruding plate portion protruding in the axial direction from the mounting plate portion to the side to which the first superconducting coil is mounted is included. The first superconducting coil is attached to a surface of the mounting plate portion opposite to the surface facing the second superconducting coil. The protruding plate portion includes an inner surface facing the outer peripheral surface of the first superconducting coil and an outer surface opposite to the inner surface. A through hole is formed in the protruding plate portion. The heat transfer portion is a first heat connection portion arranged between the end face of the first superconducting coil and the mounting plate portion so as to be thermally connected to the end face of the first superconducting coil. Along with an extension portion forming a heat transfer path extending from the first heat connection portion along the mounting plate portion, and connecting to the extension portion through the through hole of the protrusion plate portion. Includes a second thermal connection portion that is bent from the extension portion in the projecting direction of the protrusion plate portion so as to overlap the outer surface of the protrusion plate portion and is thermally connected to the refrigerator.

According to the above configuration, the protruding plate portion protruding from the mounting plate portion aligned in the axial direction with the end face of the first superconducting coil so that the plate thickness direction coincides with the axial direction is the deformation of the mounting plate portion in response to the electromagnetic force. Can be suppressed. Since the heat transfer path formed along the mounting plate portion is directly connected to the second heat connecting portion through the through hole, the edge of the protruding plate portion (that is, the edge opposite to the side connected to the mounting plate portion). It is shorter than the route that bypasses the protruding plate part so as to pass through the part). Therefore, a superconducting magnet device with a short heat transfer path and high mechanical strength is formed.

With respect to the above configuration, the superconducting magnet device further includes a reinforcing portion formed to reinforce the frame structure, and the frame structure is formed to support the second superconducting coil and the first. The second support arranged at a position separated from the first support in the axial direction is connected to the first support and the second support to form a corner portion with the first support. Including a connecting structure, the reinforcing portion with the first support so as to suppress a change in the angle of the corner portion against the electromagnetic force acting to reduce the angle of the corner portion. It is preferable that it is arranged between the connecting structure and the connecting structure.

According to the above configuration, the reinforcing portion is between the first support and the connecting structure so as to suppress the change in the angle of the corner portion against the electromagnetic force acting to reduce the angle of the corner portion. Since it is arranged in, the deformation of the frame structure is suppressed.

With respect to the above configuration, it is preferable that the reinforcing portion is arranged at the corner portion and the through hole is formed so as to be aligned with the reinforcing portion in the axial direction.

According to the above configuration, since the through hole is formed so as to be aligned with the reinforcing portion arranged at the corner of the corner in the axial direction, the through hole and the reinforcing portion are arranged at close positions. The through hole reduces the strength of the first support, but the reinforcing portion arranged near the through hole compensates for the decrease in strength caused by the formation of the through hole. Therefore, regardless of the formation of the through hole, the deformation of the first support near the corner is suppressed.

With respect to the above configuration, it is preferable that the reinforcing portion is connected to the mounting plate portion at a position adjacent to the boundary between the protruding plate portion and the mounting plate portion.

According to the above configuration, since the reinforcing portion is connected to the mounting plate portion at a position adjacent to the boundary between the protruding plate portion and the mounting plate portion, the through hole formed in the mounting plate portion is located near the reinforcing portion. is doing. Therefore, the reinforcing portion can effectively compensate for the reduced mechanical strength due to the formation of the through hole.

With respect to the above configuration, the superconducting magnet device further comprises a bobbin having an outer peripheral surface around which the first superconducting coil is wound, and the bobbin regulates the positional deviation of the first superconducting coil in the axial direction. The restricting ring portion that protrudes from the outer peripheral surface and overlaps the end surface of the first superconducting coil is included, and the restricting ring portion includes a flat annular surface facing the first thermal connection portion, and the first thermal connection portion. Preferably has a flat surface formed so as to be in close contact with the entire annular surface.

According to the above configuration, both the regulation ring portion and the first heat connection portion have a flat surface, so that a close contact structure that achieves good heat transfer between the regulation ring portion and the first heat connection portion is provided. Obtained between these flat surfaces. Since the entire annular surface of the regulation ring portion is in close contact with the first heat connection portion, the amount of heat flowing from the first superconducting coil to the first heat connection portion does not excessively fluctuate in the circumferential direction of the first superconducting coil. As a result, the occurrence of temperature unevenness of the first superconducting coil in the circumferential direction is suppressed.

With respect to the above configuration, the first thermal connection portion is between the base plate arranged between the mounting plate portion and the annular surface, and between the base plate and the annular surface so as to be in close contact with the entire annular surface. It is preferable that the thickness and rigidity of the aluminum sheet are smaller than those of the base plate, including the arranged aluminum sheet.

According to the above configuration, the wall thickness and rigidity of the aluminum sheet are smaller than those of the base plate, so that the aluminum sheet can be slightly deformed according to the surface shape of the annular surface of the base plate and the bobbin and adhere to them. Therefore, the aluminum sheet can be in closer contact with the entire annular surface as compared to the base plate in direct contact with the entire annular surface. As a result, the heat of the first superconducting coil is substantially uniformly transferred to the aluminum sheet through the bobbin portion, and the occurrence of temperature unevenness of the first superconducting coil in the circumferential direction is suppressed.

With respect to the above configuration, it is preferable that the aluminum sheet is compressed by the bobbin and the base plate in the presence of the electromagnetic force.

According to the above configuration, the aluminum sheet is compressed by the bobbin and the base plate in the presence of electromagnetic force, so that the aluminum sheet can be well adhered to the annular surface of the bobbin and the base plate. As a result, the heat of the first superconducting coil is transmitted substantially uniformly to the base plate via the bobbin portion and the aluminum sheet, and the occurrence of temperature unevenness of the first superconducting coil in the circumferential direction is suppressed.

With respect to the above configuration, the through hole is an elongated hole extended along the boundary between the projecting plate portion and the mounting plate portion, and the base plate has the extending portion and the second thermal connection portion. It is preferable that it is formed.

According to the above configuration, a long hole extending along the boundary between the projecting plate portion and the mounting plate portion is formed as a through hole, while the extending portion extends along the mounting plate portion. It forms a heat path. Therefore, the base plate and the elongated hole forming the extension portion are located on a common virtual plane along the mounting plate portion. Since these are located on a common virtual plane, a heat transfer path connecting the extension portion to the second heat connection portion is formed only by bending the base plate with an elongated hole. Since the base plate forming the extension portion and the second heat connection portion is relatively thick, the heat transferred to the base plate through the aluminum sheet is efficiently transferred to the second heat connection portion.

With respect to the above configuration, the width of the elongated holes is preferably complementary to the thickness of the base plate.

According to the above configuration, the width of the elongated hole is complementary to the thickness of the base plate, so that the elongated hole is substantially filled by the cross section of the base plate and the mechanical strength of the protruding plate portion is reduced due to the formation of the elongated hole. Is supplemented by the base plate.

The above-mentioned superconducting magnet device can support the superconducting coil under high mechanical strength and transfer the heat of the superconducting coil to the refrigerator using a short heat transfer path.

It is a schematic perspective view of the internal structure of an exemplary superconducting magnet device. It is a schematic external perspective view of a superconducting magnet device. It is a schematic perspective view of a part of the internal structure of a superconducting magnet device. It is a schematic cross-sectional view of the coil part of a superconducting magnet device. It is a schematic development perspective view of the 1st thermal connection part thermally connected to the coil part.

FIG. 1 is a schematic perspective view of the internal structure of an exemplary superconducting magnet device 100. FIG. 2 is a schematic external perspective view of the superconducting magnet device 100. The superconducting magnet device 100 will be described with reference to FIGS. 1 and 2. In the following description, terms such as "right", "left", "front", "rear", "top" and "bottom" are used. Terms that describe these directions should not be construed in a limited way for the sole purpose of clarifying the explanation.

Directional indicators such as "right", "left", "front" and "rear" are shown in FIG. In addition, FIG. 1 shows a horizontal axis HAX, an orthogonal axis PAX extending in the horizontal direction so as to be orthogonal to the horizontal axis HAX, and a vertical axis VAX orthogonal to the horizontal axis HAX and the orthogonal axis PAX. The horizontal axis HAX extends in the left-right direction. The orthogonal axis PAX extends in the front-rear direction. The vertical axis VAX extends in the vertical direction.

A virtual horizontal plane that includes an orthogonal axis PAX and a horizontal axis HAX that are orthogonal to the vertical axis VAX is referred to as a "reference horizontal plane" in the following description. The part below the reference horizontal plane is referred to as the "lower part" in the following description. The part above the reference horizontal plane is referred to as the "upper part" in the following description. A hypothetical vertical plane orthogonal to the reference horizontal plane on the horizontal axis HAX (ie, a vertical plane including the horizontal axis HAX and the vertical axis VAX) is referred to as a "reference vertical plane" in the following description. The part behind the reference vertical plane is referred to as the "rear" in the following description. The superconducting magnet device 100 will be described below with reference to a reference vertical plane, a reference horizontal plane, a horizontal axis HAX, an orthogonal axis PAX, and a vertical axis VAX.

The internal structure of the superconducting magnet device 100 receives heat from a pair of coil portions 151 and 152 that generate electromagnetic force, a frame structure formed to support the coil portions 151 and 152, and the coil portions 151 and 152. It is provided with heat transfer portions 153 and 154 formed so as to transmit. The coil portions 151 and 152 are arranged on the horizontal axis HAX at positions separated so that the central axes coincide with each other. The electromagnetic force generated from the coil portions 151 and 152 acts in the direction in which the coil portions 151 and 152 are attracted to each other. The frame structure is formed so that the separated positional relationship between the coil portions 151 and 152 is maintained against the electromagnetic force. The frame structure forms a C shape that opens forward in a plan view. The frame structure consists of a first support 161 to which the coil portion 151 and the heat transfer portion 153 are attached, a second support 162 to which the coil portion 152 and the heat transfer portion 154 are attached, and the first support 161 and the second. Includes a connecting structure coupled to the support 162. The connecting structure includes a first connecting member 191 and a second connecting member 192 whose both ends are connected to the rear ends of the first support body 161 and the second support body 162.

The internal structure of the superconducting magnet device 100 is placed in a low temperature environment (for example, 4K) in order to reduce the electrical resistance of the coil portions 151 and 152. In order to create a low temperature environment, the superconducting magnet device 100 includes a pair of refrigerators 141 and 142 (see FIG. 2). In addition, the superconducting magnet device 100 includes a vacuum vessel 110 formed to maintain a vacuum around the internal structure to maintain a low temperature environment (see FIG. 2). The vacuum vessel 110 and the refrigerators 141 and 142 are described before the detailed description of the internal structure of the superconducting magnet device 100.

The vacuum vessel 110 is formed so as to surround the internal structure shown in FIG. The internal space formed by the vacuum vessel 110 is kept in a vacuum state by a vacuum device (not shown).

The vacuum vessel 110 has a substantially U-shaped top plate 111 in a plan view, a bottom plate 112 arranged at a position downwardly separated from the top plate 111, and a peripheral wall portion substantially vertically erected from the bottom plate 112 to the top plate 111. 113 and. In addition, the vacuum vessel 110 includes four legs 114 attached to the underside of the bottom plate 112 (FIG. 2 shows two legs 114).

The top plate 111 of the vacuum vessel 110 has an inner edge 121 forming a U-shape that opens forward in a plan view, a right edge 122 extending in the front-rear direction at a position separated to the right from the inner edge 121, and an inner edge. Includes a left edge 123 extending in the front-rear direction at a position separated to the left from 121. In addition, the top plate 111 includes a trailing edge 124 extending in the left-right direction so as to connect the trailing edges of the right edge 122 and the left edge 123. Further, the top plate 111 is a front end extending in the left-right direction so as to connect the leading edge 125 extending in the left-right direction so as to connect the front ends of the inner edge 121 and the right edge 122, and the front end extending in the left-right direction so as to connect the front ends of the inner edge 121 and the left edge 123. Includes edges 126 and. The inner edge 121, right edge 122, left edge 123, trailing edge 124, and leading edge 125, 126 of the top plate 111 are arranged at substantially equal height positions. Therefore, the top plate 111 is in a substantially horizontal posture.

The bottom plate 112 is arranged substantially in parallel with the top plate 111. The bottom plate 112 is substantially equal to the top plate 111 in shape and size. The name given to the edge of the top plate 111 is applied to the bottom plate 112.

One of the four legs 114 attached to the lower surface of the bottom plate 112 is located in the leading edge region surrounded by the leading edge, right edge and inner edge of the bottom plate 112. Another leg 114 is located in the leading edge region surrounded by the leading edge, left edge and inner edge of the bottom plate 112. The other leg 114 is located at the corner formed by the trailing edge and the right edge of the bottom plate 112. The remaining one leg 114 is located at the corner formed by the trailing edge and the left edge of the bottom plate 112. These legs 114 separate the lower surface of the bottom plate 112 from the floor surface on which the superconducting magnet device 100 is installed.

The peripheral wall portion 113 forming a substantially vertical surface between the bottom plate 112 and the top plate 111 is formed of a plurality of plate members. One of the plurality of plate members is a U-shaped plate 131 forming a U-shaped surface connecting the inner edge 121 of the top plate 111 and the inner edge of the bottom plate 112. The other of the plurality of plate members is the right plate 132 forming a rectangular surface connecting the right edge 122 of the top plate 111 and the right edge of the bottom plate 112. The other of the plurality of plate members is the left plate 133 forming a rectangular surface connecting the left edge 123 of the top plate 111 and the left edge of the bottom plate 112. The other of the plurality of plate members is the rear plate 134 forming a rectangular surface connecting the trailing edge 124 of the top plate 111 and the trailing edge of the bottom plate 112. The other of the plurality of plate members is a rectangular surface connecting the leading edge 125 of the top plate 111 and the leading edge of the bottom plate 112 extending in the left-right direction below the leading edge 125 of the top plate 111. The front plate 135 forming the above. The remaining one of the plurality of plate members has a rectangular surface connecting the leading edge 126 of the top plate 111 and the leading edge of the bottom plate 112 extending in the left-right direction below the leading edge 126 of the top plate 111. It is the forming front plate 136.

The edges of the front plate 136, 135, the rear plate 134, the left plate 133, the right plate 132, the U-shaped plate 131, the bottom plate 112, and the top plate 111 are welded linearly to form a sealed internal space. Therefore, the vacuum state of the internal space surrounded by these plate-shaped members is maintained. In the internal space surrounded by these plate-shaped members, in addition to the internal structure shown in FIG. 1, a shield container (not shown) formed so as to surround the internal structure is one of the superconducting magnet devices 100. It is arranged as a department. The shielded container is used to prevent heat transfer from the external environment outside the vacuum container 110 to the internal structure arranged in the shielded container.

A part of the refrigerators 141 and 142 protruding upward from the top plate 111 of the vacuum vessel 110 is shown in FIG. The refrigerators 141 and 142 are arranged so that the vertical central axis of the refrigerators 141 and 142 is located behind the rearmost end of the inner edge 121 of the top plate 111. The refrigerator 141 is located near the corners formed by the right edge 122 and the trailing edge 124 of the top plate 111, while the refrigerator 142 is formed by the left edge 123 and the trailing edge 124 of the top plate 111. It is located near the corner of the corner.

The refrigerators 141 and 142 each have a two-stage cooling mechanism. The first stage of each of the refrigerators 141 and 142 is thermally connected to the above-mentioned shielded container. The second stage of each of the refrigerators 141 and 142 is thermally connected to the heat transfer portions 153 and 154. The phrase "thermally connected" not only means a direct connection between the two members, but also such that heat transfer occurs between the two members in the presence of intervening members intervening between the two members. It also means that these members are connected to.

The internal structure cooled in the vacuum vessel 110 by the refrigerators 141 and 142 will be described below with reference to FIGS. 1 to 3. FIG. 3 is a schematic perspective view of a part of the internal structure.

The frame structure of the internal structure includes a first support 161 arranged in the space between the right plate 132 and the U-shaped plate 131 of the vacuum vessel 110. The first support 161 is a substantially rectangular box body that opens to the right. The first support 161 has a substantially rectangular mounting plate portion 171 substantially parallel to the right plate 132 of the vacuum vessel 110, and a peripheral wall connected to the outer edge of the mounting plate portion 171 in a posture bent to the right from the outer edge of the mounting plate portion 171. Includes part 172. The plate thickness direction of the mounting plate portion 171 coincides with the circular direction of the horizontal axis HAX. A substantially circular through hole 173 is formed in the mounting plate portion 171. The horizontal axis HAX is drawn in FIG. 1 so as to pass through the center of the through hole 173 of the mounting plate portion 171. The upper and lower edges of the mounting plate portion 171 extend substantially horizontally in the front-rear direction. The leading edge and the trailing edge of the mounting plate portion 171 extend substantially vertically.

The mounting plate portion 171 is substantially vertically erected on a part of the heat transfer portion 153 and on the left side of the left end surface of the coil portion 151. The mounting plate portion 171 is arranged at a position separated from the left end surface of the coil portion 151 by the thickness of the heat transfer portion 153 in the extending direction of the horizontal axis HAX. The mounting plate portion 171 is used for mounting the heat transfer portion 153 and the coil portion 151. The mounting plate portion 171 and the peripheral wall portion 172 partially surround a part of the heat transfer portion 153 and the coil portion 151, and form a storage space in which a part of the heat transfer portion 153 and the coil portion 151 are housed.

The peripheral wall portion 172 includes three projecting plate portions 174, 175, 176. The protruding plate portions 174, 175, and 176 are mounted so as to be located on the right side of the upper edge, the lower edge and the leading edge of the mounting plate portion 171 (that is, the side to which the heat transfer portion 153 and the coil portion 151 are mounted). It protrudes from the plate portion 171. The protruding plate portion 176 on the front side is substantially parallel to the front plate 135 of the vacuum vessel 110. The upper and lower protruding plate portions 174, 175 are substantially parallel to the top plate 111 and the bottom plate 112 of the vacuum vessel 110.

A through hole 177 is formed in the rear portion of the upper protruding plate portion 174 (see FIG. 1). The through hole 177 is a long hole extending in the front-rear direction along the boundary between the mounting plate portion 171 and the protruding plate portion 174 (that is, the ridge line formed by the mounting plate portion 171 and the protruding plate portion 174). Is. The through hole 177 is formed between the boundary between the mounting plate portion 171 and the protruding plate portion 174 and the refrigerator 141.

The lower surface of the upper protruding plate portion 174 faces in a direction facing the outer peripheral surface of the coil portion 151 fixed in the accommodation space formed by the mounting plate portion 171 and the peripheral wall portion 172. The lower surface of the protruding plate portion 174 is referred to as "inner surface 178" in the following description. The surface opposite to the inner surface 178 (that is, the upper surface of the protruding plate portion 174) is referred to as "outer surface 179" in the following description.

A coil portion 151 arranged in the accommodation space formed by the projecting plate portions 174, 175, 176 and the mounting plate portion 171 is fixed to the right surface of the mounting plate portion 171 (see FIG. 3). A schematic cross-sectional view of the coil portion 151 is shown in FIG. The coil portion 151 will be described with reference to FIGS. 1, 3 and 4.

The coil portion 151 includes a pair of bobbins 156,158 and a pair of superconducting coils 155,157 wound around the outer peripheral surfaces of these bobbins 156,158. The bobbins 156 and 158 have a central axis that substantially coincides with the horizontal axis HAX. That is, the bobbin 156 is arranged substantially concentrically with the bobbin 158. The inner diameter of the bobbin 156 is larger than the outer diameter of the bobbin 158. The bobbin 158 is arranged in the bobbin 156. The bobbins 156 and 158 have a substantially C-shaped cross section that opens in the outer peripheral direction.

The bobbin 156 has a cylindrical portion 211 extending along the horizontal axis HAX, and a regulation ring portion 212 protruding from the left end and the right end of the outer peripheral surface of the cylindrical portion 211 so as to overlap the left end surface and the right end surface of the superconducting coil 155. 213 and. A superconducting coil 155 is wound around the outer peripheral surface of the cylindrical portion 211. The regulating ring portions 212 and 213 are formed so as to regulate the positional deviation of the superconducting coil 155 in the extending direction of the horizontal axis HAX. The regulation ring portion 212 on the left side has a flat annular surface. The annular surface of the regulating ring portion 212 forms a part of the left end surface of the bobbin 156 and is in close contact with the heat transfer portion 153.

The bobbin 158 in the bobbin 156 includes a cylindrical portion 214 extending along the horizontal axis HAX, and restricting ring portions 215 and 216 protruding outward from the left and right ends of the outer peripheral surface of the cylindrical portion 214. A superconducting coil 157 is wound around the outer peripheral surface of the cylindrical portion 211 of the bobbin 158. The axial length of the cylindrical portion 214 of the bobbin 158 is substantially equal to the axial length of the cylindrical portion 211 of the bobbin 156, while the cylindrical portion 214 of the bobbin 158 is thinner than the cylindrical portion 211 of the bobbin 156. The regulation ring portions 215 and 216 of the bobbin 158 are formed so as to regulate the positional deviation of the superconducting coil 157 in the extending direction of the horizontal axis HAX. The regulation ring portions 215 and 216 of the bobbin 158 are smaller in outer diameter and inner diameter than the regulation ring portions 212 and 213 of the bobbin 156. The regulation ring portion 215 on the left side has a flat annular surface. The annular surface of the regulation ring portion 215 forms a part of the left end surface of the bobbin 158 and is in close contact with the heat transfer portion 153.

Superconducting coils 155 and 157 are formed from superconducting wires wound around the outer peripheral surfaces of the cylindrical portions 211 and 214 of the bobbins 156 and 158, respectively. Like the bobbins 156 and 158, the superconducting coils 155 and 157 have a central axis that substantially coincides with the horizontal axis HAX. The superconducting coil 157 wound around the bobbin 158 is arranged in the superconducting coil 155 wound around the bobbin 156.

The heat transfer section 153 is formed so as to obtain a heat transfer path from the superconducting coils 155 and 157 to the refrigerator 141. The heat transfer section 153 has a substantially rectangular shape that is thermally connected to the second stage of the refrigerator 141 and the annular first heat connection section 183 that is thermally connected to the superconducting coils 155, 157 and the bobbins 156, 158. The second thermal connection portion 182 of the above is provided. In addition, the heat transfer section 153 includes a substantially triangular extending section 184 forming a heat transfer path extending from the first heat connecting section 183 along the mounting plate section 171. The extension portion 184 is not only connected to the first heat connection portion 183 but also to the second heat connection portion 182 via the through hole 177 of the upper protruding plate portion 174. The first heat connection portion 183 is formed of a plurality of heat conductive materials, while the extension portion 184 and the second heat connection portion 182 are formed of a single heat conductive material. The first heat connection portion 183 is arranged between the right surface of the mounting plate portion 171 and the left end surface of the bobbins 156,158. The second heat connection portion 182 is bent from the extension portion 184 in the projecting direction of the projecting plate portion 174 and overlaps with the outer surface 179 of the projecting plate portion 174. The second heat connection portion 182 is arranged between the second stage of the refrigerator 141 and the outer surface 179 of the upper protruding plate portion 174. The second heat connection portion 182 is fixed to the outer surface 179 of the protrusion plate portion 174 together with the second stage of the refrigerator 141. The second heat connection portion 182 is located at the downstream end of the heat transfer path from the superconducting coils 155 and 157. On the other hand, the upstream end of the heat transfer path is formed by the first heat connection portion 183.

A schematic developed perspective view of the first thermal connection portion 183 is shown in FIG. A schematic cross-sectional view (cross-sectional view on a reference horizontal plane) of the first thermal connection portion 183 is shown in FIG. The heat transfer unit 153 will be described with reference to FIGS. 1, 3 to 5.

The heat transfer unit 153 includes a base plate 186 having a predetermined thermal conductivity and an aluminum sheet 187 (see FIG. 5) which is thinner and has lower rigidity than the base plate 186. The base plate 186 has a thickness complementary to the width of the elongated hole formed as the through hole 177. For example, the base plate 186 may be a copper plate having a thickness of about 10 mm. The base plate 186 may be formed of electrolytic copper or oxygen-free copper. The base plate 186 was bent from the upstream plate portion 188 through the through hole 177 and overlapped with the outer surface 179 of the upper protruding plate portion 174 and the upstream plate portion 188 forming the first heat connection portion 183 and the extension portion 184. Includes the downstream plate portion 189. The downstream plate portion 189 forms a second thermal connection portion 182.

The right edge of the downstream plate portion 189 is substantially flush with the right edge of the protruding plate portion 174. The downstream plate portion 189 extends to the left from the right edge of the protruding plate portion 174. The dimension in the front-rear direction of the protrusion plate portion 174 is slightly smaller than the dimension in the front-rear direction of the through hole 177 formed in the protrusion plate portion 174. The left edge of the protruding plate portion 174 is located on the through hole 177. The base plate 186 is bent downward on the through hole 177. The lower portion of the through hole 177 is the upstream plate portion 188.

The through hole 177 is formed near the left surface of the mounting plate portion 171. The upstream plate portion 188 located below the through hole 177 takes a vertical posture along the mounting plate portion 171 and overlaps with the mounting plate portion 171. The upstream plate portion 188 is fixed to the mounting plate portion 171 using bolts or other fixing tools.

The upstream plate portion 188 extends forward from the position below the through hole 177 to form an extension portion 184. Further in front of the extension portion 184, the upstream plate portion 188 forms the first heat connection portion 183. An aluminum sheet 187 is superposed on the portion of the upstream plate portion 188 forming the first heat connection portion 183. The upstream plate portion 188 is located between the aluminum sheet 187 and the mounting plate portion 171. A part of the upstream plate portion 188 (that is, a portion located in front of the extension portion 184) and the aluminum sheet 187 form the first heat connection portion 183.

The aluminum sheet 187 is arranged on the right side of the upstream plate portion 188, and is sandwiched between the upstream plate portion 188 and the coil portion 151 (that is, the left end surface of the bobbins 156, 158). Both the left surface of the aluminum sheet 187 and the right surface of the upstream plate portion 188 are flat, and these surfaces are in close contact with each other. The right surface of the aluminum sheet 187 is also flat, and is in close contact with the flat annular surface of the regulation ring portions 212 and 215 of the bobbins 156 and 158. The aluminum sheet 187 is made of high-purity aluminum of 99.999%. The aluminum sheet 187 is much thinner than the base plate 186 and has a thickness of about 0.25 mm.

The aluminum sheet 187 is annular, and the center of the aluminum sheet 187 is arranged so as to substantially coincide with the horizontal axis HAX. The inner diameter of the aluminum sheet 187 substantially matches the inner diameter of the bobbin 158. The outer diameter of the aluminum sheet 187 substantially matches the outer diameter of the bobbin 156. Therefore, the right surface of the aluminum sheet 187 is in close contact with the entire left end surface of the coil portion 151. The entire left surface of the aluminum sheet 187 is in close contact with the right surface of the upstream plate portion 188.

The assembly including the coil portion 151, the heat transfer portion 153, and the first support 161 has a mirror image relationship with the assembly including the coil portion 152, the heat transfer portion 154, and the second support 162 with respect to the reference vertical plane. Therefore, the description of the coil portion 151, the heat transfer portion 153, and the first support 161 is incorporated into the assembly including the coil portion 152, the heat transfer portion 154, and the second support 162 in consideration of the mirror image relationship. The assembly including the coil portion 152, the heat transfer portion 154, and the second support 162 is arranged in the space between the U-shaped plate 131 and the left plate 133 of the vacuum vessel 110, and the coil portion 151, the heat transfer portion 153, and the second support portion 162 are arranged. It is separated from the assembly composed of one support 161 in the extending direction of the horizontal axis HAX.

When electric power is supplied to the coil portions 151 and 152, an electromagnetic force acting substantially parallel to the horizontal axis HAX acts to attract the above-mentioned pair of assemblies to each other. In order to maintain the mirror image positional relationship of these assemblies under the generation of electromagnetic force, the first connecting member 191 and the second connecting member 192 form a connecting structure that connects these assemblies. The first connecting member 191 and the second connecting member 192 are arranged at positions separated rearward from the horizontal axis HAX (that is, in the extending direction of the orthogonal axis PAX). The first connecting member 191 and the second connecting member 192 extend substantially parallel to the horizontal axis HAX.

The first connecting member 191 has a lower surface that is substantially flush with the lower surfaces of the first support 161 and the second support 162, while the second connecting member 192 is the upper surface of the first support 161 and the second support 162. It has an upper surface that is substantially flush with each other. The intermediate position in the height direction between the lower surface of the first connecting member 191 and the upper surface of the second support 162 substantially coincides with the reference horizontal plane. The first connecting member 191 extends substantially horizontally in the left-right direction so as to be connected to the rear ends of the lower portions of the first support body 161 and the second support body 162. The second connecting member 192 is substantially horizontally extended in the left-right direction so as to be connected to the rear ends of the upper portions of the first support body 161 and the second support body 162 at a position separated upward from the first connecting member 191. There is. General square pipes can be used as the first connecting member 191 and the second connecting member 192.

The first connecting member 191 and the second connecting member 192 maintain a mirror image positional relationship between the first support body 161 and the second support body 162 to some extent. It was attached to the first support 161 and the second support 162 so that the first connecting member 191 and the second connecting member 192 alone could not obtain sufficient structural strength to maintain the above-mentioned positional relationship. When the electromagnetic force acting between the coil portions 151 and 152 is very strong, the superconducting magnet device 100 is formed by the first connecting member 191 and the second connecting member 192, the first support body 161 and the second support body 162. It is preferable to have a reinforcing structure for reinforcing the frame structure.

Four reinforcing portions 201 are used as the reinforcing structure. One of the four reinforcing portions 201 is arranged at a corner formed by the first connecting member 191 and the left surface of the mounting plate portion 171 of the first support 161 and welded to them (FIG. 3). reference). The weld line between the reinforcing portion 201 and the mounting plate portion 171 extends substantially parallel to the boundary near the boundary between the mounting plate portion 171 and the upper protruding plate portion 174, and the boundary is between the weld line and the through hole 177. Is located in. Therefore, the reinforcing portions 201 are lined up in the extending direction of the horizontal axis HAX of the through hole. The other of the four reinforcing portions 201 is arranged at a corner formed by the second connecting member 192 and the left surface of the mounting plate portion 171 of the first support 161 and welded to them (). See Figure 1). The other of the four reinforcing portions 201 is arranged at a corner formed by the second connecting member 192 and the right surface of the mounting plate portion of the second support 162 and welded to them (FIG. FIG. See 1). The remaining one of the four reinforcing portions 201 is arranged and welded to the corner portion formed by the first connecting member 191 and the right surface of the mounting plate portion of the second support 162 (FIG. 1). See).

The structure of the reinforcing portion 201 welded to the right surface of the mounting plate portion of the first connecting member 191 and the second support 162 will be described below. The reinforcing portion 201 welded to the right surface of the mounting plate portion of the first connecting member 191 and the second support body 162 is a reinforcement welded to the right surface of the mounting plate portion of the second connecting member 192 and the second support body 162. It is common in shape and size to the part 201. Therefore, the following description of the reinforcing portion 201 welded to the right surface of the mounting plate portion of the first connecting member 191 and the second support 162 is described on the right surface of the mounting plate portion of the second connecting member 192 and the second support body 162. It is used for the reinforcing portion 201 welded to and. The other two reinforcing portions 201 are in a mirror image relationship with the two reinforcing portions 201 welded to the second support 162 with respect to the reference vertical plane. Therefore, the following description of the reinforcing portion 201 welded to the right surface of the mounting plate portion of the first connecting member 191 and the second support 162 is two welded to the first support 161 in consideration of the mirror image relationship. It is used for the reinforcing portion 201.

The reinforcing portion 201 welded to the right surface of the mounting plate portion of the first connecting member 191 and the second support 162 includes two horizontal plates 202 and 203 in a horizontal posture and a vertical plate 204 in a vertical posture. The horizontal plates 202 and 203 are equal in shape and size, and are substantially right triangle-shaped plates. The hypotenuses of the substantially right triangles formed by the horizontal plates 202 and 203 are curved so as to follow the curvature of the U-shaped plate 131 of the vacuum vessel 110. One of the other sides of the substantially right triangle formed by the horizontal plates 202 and 203 extends in the extending direction of the first connecting member 191 and is welded to the outer peripheral surface of the first connecting member 191. The remaining sides of the substantially right triangle formed by the horizontal plates 202 and 203 extend forward and are welded to the right surface of the mounting plate portion of the second support 162.

The water plate 202 is separated upward from the horizontal plate 203. A vertical plate 204 is arranged between the water plates 202 and 203. The vertical plate 204 is a substantially rectangular flat plate. The upper edge of the vertical plate 204 is welded to the lower surface of the horizontal plate 202. The lower edge of the vertical plate 204 is welded to the upper surface of the horizontal plate 203. The trailing edge of the vertical plate 204 is welded to the outer peripheral surface of the first connecting member 191.

The reinforcing portion 201 formed by the vertical plate 204 and the horizontal plates 202 and 203 deforms the frame structure formed by the first connecting member 191 and the second connecting member 192, the first support 161 and the second support 162. Effectively prevent. A strong electromagnetic force generated under the power supply to the coil portions 151 and 152 acts so as to attract the first support body 161 and the second support body 162. At this time, at the connecting portion of the first support body 161 and the first connecting member 191 (and the second connecting member 192), the left surface of the mounting plate portion 171 of the first support body 161 and the first connecting member 191 (and the second connecting member 191) are connected. A moment that tries to narrow the narrowing angle (that is, the angle of the corner portion) formed in the plan view with the member 192) acts. Similarly, at the connecting portion of the second support 162 and the first connecting member 191 (and the second connecting member 192), the right surface of the mounting plate portion of the second support 162 and the first connecting member 191 (and the second connecting member 191) are connected. A moment that tries to narrow the sandwiching angle formed in the plan view with the member 192) acts. When these sandwiches change, the axes of the coil portions 151 and 152 deviate from the horizontal axis HAX. However, the four reinforcing portions 201 arranged at the formation sites of these pinching angles resist the above-mentioned moments.

Since the vertical plate 204 arranged between the water plates 202 and 203 prevents bending deformation of the horizontal plates 202 and 203 upward or downward, the reinforcing portion 201 can sufficiently resist the moment. The reinforcing portion 201 maintains the shape of the frame structure even in the presence of a strong electromagnetic force.

One of the four reinforcing portions 201 is arranged at the corner portion formed by the mounting plate portion 171 of the first connecting member 191 and the first support body 161. A through hole 177 is formed near the reinforcing portion 201. That is, the reinforcing portion 201 and the through hole 177 are arranged at substantially the same height position and substantially the same rear position. In other words, the through hole 177 is formed closer to the reinforcing portion 201 than the reference horizontal plane (a virtual horizontal plane including the horizontal axis HAX and the orthogonal axis PAX) in the extending direction of the vertical axis VAX. In addition, the through hole 177 is formed closer to the reinforcing portion 201 than the reference vertical plane (virtual vertical plane including the horizontal axis HAX and the vertical axis VAX) in the extending direction of the orthogonal axis PAX. The through hole 177 slightly reduces the strength of the frame structure around the corners of the frame structure, while the reinforcing portion 201 improves the strength of the frame structure around the corners of the frame structure. Therefore, the formation of the through hole 177 does not pose a particular problem in terms of the strength of the frame structure.

Since the frame structure is reinforced by the reinforcing portion 201, the risk that the axes of the coil portions 151 and 152 deviate from the horizontal axis HAX is reduced even if a large electromagnetic force is generated from the coil portions 151 and 152. In order to generate a large electromagnetic force from the coil portions 151 and 152, the refrigerators 141 and 142 operate to take heat from the coil portions 151 and 152. The flow of heat from the coil portion 151 to the refrigerator 141 will be described below. The description of the heat flow from the coil unit 151 to the refrigerator 141 is incorporated into the heat flow from the coil unit 152 to the refrigerator 142.

The left end surface of the coil portion 151 is in contact with the right surface of the aluminum sheet 187. The left surface of the aluminum sheet 187 is in contact with the right surface of the upstream plate portion 188. Since the aluminum sheet 187 is very thin and has low rigidity, the surface of the aluminum sheet 187 is slightly deformed according to the surface shape of the contact portion, and is in close contact with the left end surface of the coil portion 151 and the right surface of the upstream plate portion 188. Can be done. Since the aluminum sheet 187 is compressed by the coil portion 151 and the upstream plate portion 188 in the presence of electromagnetic force, the degree of adhesion of the aluminum sheet 187 to the coil portion 151 and the upstream plate portion 188 becomes very high. Therefore, the heat of the coil portion 151 is efficiently transferred to the upstream plate portion 188 through the aluminum sheet 187. Since the upstream plate portion 188 and the downstream plate portion 189 are relatively thick, the heat of the coil portion 151 is efficiently transferred from the upstream plate portion 188 to the downstream plate portion 189.

The heat of the coil portions 151 and 152 is taken away by the refrigerators 141 and 142 through the heat transfer portions 153 and 154. As a result, the coil portions 151 and 152 become extremely low temperature (for example, 4K), and the resistance to the electric power supplied to the coil portions 151 and 152 becomes very low. As a result of a large current flowing through the coil portions 151 and 152, a large electromagnetic force is generated between the coil portions 151 and 152. In the space between the first support 161 and the second support 162 to which the coil portions 151 and 152 are attached, for example, a crucible containing a molten material to be processed into a semiconductor wafer is moved in the vertical direction. As a result, the impurities in the molten material are collected on the inner wall surface of the crucible by the high electromagnetic force generated from the coil portions 151 and 152, while the high-purity semiconductor material is collected in the center of the crucible. The superconducting magnet device 100 may be used for purposes other than removing impurities. Therefore, the use of the superconducting magnet device 100 should not be construed in a limited way.

The attachment of the base plate 186 to the first support 161 of the superconducting magnet device 100 is simple. A copper flat plate processed into a predetermined shape may be prepared as the base plate 186. The copper plate is arranged so that a part of the copper plate protrudes upward through the through hole 177 while the rest of the copper plate is along the right surface of the mounting plate portion 171. After the portion overlapping the right surface of the mounting plate portion 171 is fixed to a bolt or other fixture, the portion protruding upward through the through hole 177 is bent to the right. As a result, the upstream plate portion 188 and the downstream plate portion 189 that overlap the right surface of the mounting plate portion 171 are formed.

The bent structure between the upstream plate portion 188 and the downstream plate portion 189 may be formed before the base plate 186 is fixed to the first support 161. When the upstream plate portion 188 is held so as to be substantially horizontal, the downstream plate portion 189 projects upward. After that, the base plate 186 is arranged so that the downstream plate portion 189 protruding upward is located below the through hole 177. When the base plate 186 is moved upward, the downstream plate portion 189 protruding upward is inserted into the through hole 177. After that, when the base plate 186 is rotated by about 90 ° around the boundary between the downstream plate portion 189 and the upstream plate portion 188, the upstream plate portion 188 follows the right surface of the mounting plate portion 171 while the downstream plate portion 189 is a protruding plate portion. Along the outer surface 179 of 174. After that, the upstream plate portion 188 is fixed to the mounting plate portion 171 while the downstream plate portion 189 is fixed to the protruding plate portion 174 together with the refrigerator 141.

The through hole 177 formed in the projecting plate portion 174 is an elongated hole having a width complementary to the thickness of the base plate 186. Therefore, the through hole 177 is almost filled with the cross section of the base plate 186. As a result of the formation of the through hole 177, the mechanical strength of the protruding plate portion 174 is slightly reduced, but the strength reduction is substantially offset by the base plate that fills the through hole 177.

After a part of the upstream plate portion 188 (that is, the portion forming the extension portion 184) is fixed to the mounting plate portion 171, the aluminum sheet 187 is overlapped with the upstream plate portion 188 and the first heat connection portion 183 is formed. It is formed. After that, the coil portion 151 is attached to the first heat connection portion 183. The coil portion 151 is fixed to the mounting plate portion 171 together with the aluminum sheet 187 and the upstream plate portion 188. As a result, a structure is formed in which the aluminum sheet 187 is interposed between the coil portion 151 and the upstream plate portion 188. However, if the smoothness of the left end surface of the coil portion 151 and the right surface of the upstream plate portion 188 is high and a high degree of adhesion between them can be obtained, the aluminum sheet 187 is not required.

The protruding plate portions 174, 175, and 176 are connected in a bent posture to the mounting plate portion 171 to which the coil portion 151 and the upstream plate portion 188 are attached. As a result of the bent structure of the mounting plate portion 171 and the protruding plate portions 174, 175, 176, the first support 161 has high mechanical strength. The bending structure of the mounting plate portion 171 and the protruding plate portions 174, 175, 176 may be formed by bending or welding.

If the bent structures of the mounting plate portion 171 and the protruding plate portions 174, 175, 176 have sufficiently high strength even under the formation of the through hole 177, the reinforcing portion 201 may not be used.

The technique of the above-described embodiment is suitably used in various technical fields in which a strong electromagnetic force is required.

100 ... Superconducting magnet device 141 ... Refrigerator 151 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Superconducting coil (1st superconducting coil)
156, 158 ... Bobbin 161 ... First support 162 ... Second support 171 ... Mounting plate 174 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Protruding plate 177 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Through hole 178 ・ ・ ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner surface 179 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outer surface 182 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ 2nd heat connection part 183 ・ ・ ・ ・ ・ ・ ・ ・ ・ 1st heat connection part 184 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ ・ Extension part 186 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Base plate 187 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ Aluminum sheet 188 ・ ・ ・ ・ ・ ・ ・ ・ ・ Upstream plate 189 ・ ・ ・ ・ ・ ・ ・ ・・ ・ Downstream plate part 201 ・ ・ ・ ・ ・ ・ ・ ・ ・ Reinforcement part 212,215 ・ ・ ・ ・ ・ Restriction ring part

Claims (9)

The first superconducting coil and the second superconducting coil, which are arranged so as to face each other at positions separated in the axial direction and generate electromagnetic forces acting in the directions of attracting each other, respectively.
A frame structure formed to support the first superconducting coil and the second superconducting coil, and
A heat transfer unit formed to transfer the heat of the first superconducting coil,
A refrigerator that is thermally connected to the heat transfer unit is provided.
The frame structure is aligned with the end face of the first superconducting coil in the axial direction so that the plate thickness direction coincides with the axial direction, and the mounting plate to which the first superconducting coil is attached via the heat transfer portion. A first support having a portion and a protruding plate portion protruding in the axial direction from the mounting plate portion to the side to which the first superconducting coil is mounted.
The first superconducting coil is mounted on a surface of the mounting plate portion opposite to the surface facing the second superconducting coil.
The protruding plate portion includes an inner surface facing the outer peripheral surface of the first superconducting coil and an outer surface opposite to the inner surface.
A through hole is formed in the protruding plate portion, and a through hole is formed.
The heat transfer portion is a first heat connection portion arranged between the end face of the first superconducting coil and the mounting plate portion so as to be thermally connected to the end face of the first superconducting coil. Along with an extension portion forming a heat transfer path extending from the first heat connection portion along the mounting plate portion, and connecting to the extension portion through the through hole of the protrusion plate portion. A superconducting magnet device including a second heat connection portion that is bent from the extension portion in the protrusion direction of the protrusion plate portion so as to overlap the outer surface of the protrusion plate portion and is thermally connected to the refrigerator. .. Further provided with a reinforcing portion formed to reinforce the frame structure,
The frame structure is formed so as to support the second superconducting coil, and has a second support arranged at a position axially separated from the first support, and the first support. Including a connecting structure that is connected to the second support and forms a corner portion with the first support.
The reinforcing portion is between the first support and the connecting structure so as to resist the electromagnetic force acting to reduce the angle of the corner portion and suppress the change in the angle of the corner portion. The superconducting magnet device according to claim 1, which is arranged. The reinforcing portion is arranged at the corner portion, and the reinforcing portion is arranged at the corner portion.
The superconducting magnet device according to claim 2, wherein the through hole is formed so as to be aligned with the reinforcing portion in the axial direction. The superconducting magnet device according to claim 3, wherein the reinforcing portion is connected to the mounting plate portion at a position adjacent to a boundary between the protruding plate portion and the mounting plate portion. A bobbin having an outer peripheral surface around which the first superconducting coil is wound is further provided.
The bobbin includes a regulating ring portion that protrudes from the outer peripheral surface and overlaps with the end surface of the first superconducting coil so as to regulate the positional deviation of the first superconducting coil in the axial direction.
The restricting ring portion comprises a flat annular surface facing the first thermal connection portion.
The superconducting magnet device according to any one of claims 1 to 4, wherein the first thermal connection portion has a flat surface formed so as to be in close contact with the entire annular surface. The first thermal connection portion is a base plate arranged between the mounting plate portion and the annular surface, and aluminum arranged between the base plate and the annular surface so as to be in close contact with the entire annular surface. Including the sheet,
The superconducting magnet device according to claim 5, wherein the thickness and rigidity of the aluminum sheet are smaller than those of the base plate. The superconducting magnet device according to claim 6, wherein the aluminum sheet is compressed by the bobbin and the base plate in the presence of the electromagnetic force. The through hole is an elongated hole extending along the boundary between the projecting plate portion and the mounting plate portion.
The superconducting magnet device according to claim 6 or 7, wherein the base plate forms the extension portion and the second thermal connection portion. The superconducting magnet device according to claim 8, wherein the width of the elongated hole is complementary to the thickness of the base plate.

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