JP2011210421A - Method and device for connecting superconductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device in which superconductors are connected by a simple connection work by maintaining a low resistance of the connection part of the superconductors.SOLUTION: The superconductor has a channel formed in the central part and superconductive element wire bundle is arranged at the surrounding. The portion exposed from the end part of conduit of the superconductive element wire bundle is covered by a conductive member in the condition lacking the channel. Then, using a plurality of molding dies which are arranged separated with prescribed intervals in circumference direction of the conductive member, and have a pressing surface recessed in arc shape with a prescribed curvature, the conductive member is arranged in a cavity formed by these plurality of molding dies. Then, the conductive member is pressed by the pressing surface of the plurality of molding dies to reduce the diameter, and the diameter-reduced conductive member and the conductive member which is reduced in diameter covering the surrounding of the superconductive element wire bundle of the another superconductor formed by the process are insertion engaged with a groove formed in the conductive connection body, and are jointed electrically and mechanically.

Description

  The present invention relates to a superconducting conductor connection method and a superconducting conductor connection apparatus.

  Large superconducting coils that generate high magnetic fields, such as fusion devices and superconducting energy storage system devices, and superconducting coils used for power transmission lines, etc. are generally prepared by connecting multiple superconducting conductors to each other. Manufacture.

  For example, in Patent Document 1, the conduits of both superconducting conductors are removed to expose a filament of a certain length from the superconducting wire with nitric acid and the like, and both filaments are stacked for each appropriate number of bundles. Is covered with a connecting piece, a predetermined temperature and pressure are applied to solid-phase-bond the filament and the stabilized copper, and both conductors are integrated. Further, Patent Document 2 discloses a method in which a stabilizer is removed from both superconducting wires to expose a filament, and a heat treatment is performed while applying pressure by superposing each other.

  In Patent Document 3, the stabilizer at the connection end is removed from both compound-based superconducting wires, and then the tube-shaped filaments are superposed on each other to apply pressure and temperature, so that a solid phase is formed between the tube-shaped filaments. A method for diffusion bonding is disclosed. Patent Document 4 discloses a connection method using a butt joint method in which both ends of a superconducting conductor to be connected are swaged and integrated with a copper sleeve, and these ends are connected together. .

  Further, in Patent Document 5, 49 strands having a structure in which about 10,000 superconducting filaments are embedded are bundled and further covered with a conduit to form a composite conductor having a predetermined outer diameter. Peel off the inner wire by removing it at a length of 200 mm, process each strand so that the cross section has a hexagonal shape with a processing roll, and then insert each processed strand into a copper mold Thus, a total of seven blocks are formed. Thereafter, the seven blocks are swaged into a regular hexagonal shape to obtain a plurality of sixth-order rotationally symmetric composite conductors, and the ends of the plurality of composite conductors are brought into contact with each other, whereby the plurality of composite conductors are obtained. That is, a method of connecting superconducting filaments is disclosed.

  Further, in Patent Document 6, a superconducting filament is inserted into a sleeve, and then the sleeve is inserted into a mold composed of, for example, an upper frame and a lower frame, and the contact surfaces of the upper frame and the lower frame hit each other. A method is disclosed in which superconducting filaments are connected to each other within the sleeve by pressing the sleeve until the diameter is reduced.

JP-A-6-163140 JP-A 63-55875 Japanese Patent Application Laid-Open No. 2-197017 JP-A-10-21976 Japanese Patent Laid-Open No. 8-13821 JP-A-6-196341

  However, in the connection methods disclosed in Patent Documents 1 to 6 described above, although there is an advantage in reducing the resistance and compactness of the connection portion compared to the method by soldering, both are stabilized from both superconducting wires. Since the material was a method that required the step of exposing the filament by dissolving and removing the stabilized copper using an acid such as a nitric acid solution, the handling of the superconducting wire filament and the stabilizing material became complicated, The work efficiency was not always good.

  For example, since the filament is an ultrathin wire of several tens of μm, the filament may ignite due to friction between the filaments in handling, or if the cleaning after connection is poor, the filament in the connection part is oxidized and the connection resistance There was a problem that the specification value of the connection resistance required from the device design was not cleared because the value increased. In addition, when removing the stabilizer, a process using a strong acid such as a nitric acid solution was indispensable, so there were many restrictions on the handling of the solution and the work environment in the connection work area, and the workability was efficient. It was not a thing.

  In addition, the connection method described in Patent Document 4 is such that a heat-treated superconducting conductor is subjected to advanced processing (flatness, perpendicularity, roughness, cleanliness, etc.) on the end face to be connected, and a vacuum or an inert gas atmosphere Inside, a connection with a predetermined low resistance can be obtained under conditions of heating (for example, around 700 ° C.) and pressurization (for example, 1 to 10 MPa). Therefore, extremely advanced technology and connection devices have been required.

  Furthermore, in the method described in Patent Document 5, when the composite conductor described above is obtained, each element wire exposed from the conduit is processed by a processing roll, so that the process becomes complicated. Further, in the method described in Patent Document 6, the diameter of the superconducting filament in the sleeve can be reduced only until the contact surfaces of the upper frame and the lower frame come into contact with each other. As a result, there is a problem that the resistance increases and sufficient superconducting characteristics cannot be obtained.

  An object of the present invention is to provide a method and an apparatus for connecting superconducting conductors with a simple connection operation while maintaining a low resistance of the connecting portion of the superconducting conductors.

  One aspect of the present invention is a method of connecting a superconducting conductor in which a superconducting wire bundle in which a channel of a refrigerant passage is formed in a central portion is accommodated in a conduit, and a portion of the superconducting wire bundle exposed from a conduit end is A covering step of covering with a conductive member in a state lacking the channel, and a plurality of molds having pressing surfaces that are spaced apart at predetermined intervals in the circumferential direction of the conductive member and recessed in an arc shape with a predetermined curvature And a step of arranging the conductive member in a cavity formed by the plurality of molds, and a step of reducing the diameter by pressing the conductive member with the pressing surfaces of the molds. The reduced-diameter conductive member and the reduced-diameter conductive member covering the periphery of the superconducting wire bundle of another superconducting conductor formed in the above process are fitted into the groove formed in the conductive connector. Combine A bonding step of electrically and mechanically joined, characterized in that it comprises a related method for connecting a superconducting conductor (first connection).

  Further, according to one aspect of the present invention, a superconducting conductor bundle of superconducting conductors is covered with a covering step in which a portion exposed from the end of the conduit is covered with a conductive member, and spaced apart at a predetermined interval in the circumferential direction of the conductive member. An arrangement step of arranging the conductive member in a cavity formed by the plurality of molding dies using a plurality of molding dies having a pressing surface recessed in an arc shape with a predetermined curvature; and The diameter reducing step of pressing the conductive member with the pressing surface to reduce the diameter, the reduced diameter of the conductive member, and the diameter of the superconducting wire bundle of another superconducting conductor formed in the above step. A superconducting conductor connection method comprising: a step of fitting the conductive member into a groove formed in a conductive connection body to electrically and mechanically join the conductive member. 2nd connection method).

  Furthermore, according to one aspect of the present invention, a superconducting wire bundle in a superconducting conductor is disposed at predetermined intervals in the circumferential direction of a conductive member that covers a portion exposed from the end of the conduit, and has a circular shape with a predetermined curvature. A plurality of molds for reducing the diameter of the conductive member having a pressing surface recessed in an arc shape, and a pressing force for reducing the diameter of the conductive member to the plurality of molds And a cylindrical holding member for holding the plurality of molds and the pressure supply means. The present invention relates to a superconducting conductor connection device.

  According to the first connection method and the second connection method described above, a portion exposed from the conduit end of the superconducting wire bundle in the superconducting conductor is covered with the conductive member, and then predetermined in the circumferential direction of the conductive member. Are pressed with a plurality of molds having a pressing surface that is recessed in an arc shape with a predetermined curvature, that is, a R-shaped pressing surface, so as to reduce the diameter. Therefore, it is possible to reduce the gaps between the plurality of superconducting wires constituting the superconducting wire exposed from the conduit, and to realize a reduction in resistance of the superconducting wire. That is, the resistance of the superconducting wire bundle used for connection of the superconducting conductor can be reduced.

  In addition, since the diameter of the superconducting wires exposed from the conduit is reduced at a time instead of every wire, the process of reducing the resistance accompanying the diameter reduction can be simplified.

  Furthermore, for superconducting conductor connection, after reducing the resistance of the superconducting conductor as described above, a conductive member having a reduced diameter covering the superconducting wire bundle is fitted into a groove formed in the conductive connecting body. In addition, a conductive member having a reduced diameter of another superconducting conductor formed in the same manner is fitted into a groove formed in the connection body, and indirectly connected through the connection body. Yes. Therefore, the superconducting conductor and another superconducting conductor can be joined very easily.

  In addition, although the basic connection method in the 1st connection method and the 2nd connection method which were mentioned above, and the effect accompanying it are mutually the same, it provides for a connection in the 1st connection method and the 2nd connection method. The basic configuration of the superconducting conductor is different. That is, in the first connection method, the superconducting conductor provided for connection has a structure in which a channel is formed at the center and a superconducting wire bundle is disposed around the channel. In the second connection method, The superconducting conductor provided for connection has a structure in which a channel is not formed in the central part but a superconducting wire bundle is formed.

  In one example of the present invention, the diameter reducing step includes rotating a plurality of molding dies at least once at a predetermined angle around the conductive member by using a predetermined rotating mechanism to reduce the diameter of the plurality of conductive members. A step of pressing a non-pressing portion caused by a gap generated between adjacent molds of the molds with the pressing surfaces of the plurality of molds.

  In both of the first connection method and the second connection method described above, the conductive member covering the superconducting element wire bundle exposed from the conduit is shrunk at once to a predetermined diameter using a plurality of molds. Since it is difficult to reduce the diameter, the diameter reduction is usually performed in multiple steps. At this time, in the initial diameter reduction, when pressing the conductive member with a plurality of molds, adjacent molds are separated from each other without being in close contact with each other. In such a case, the non-pressing part resulting from the gap which arises between adjacent molds will be formed. This non-pressing portion is formed as a protrusion with respect to the pressing surface (reduced diameter surface) of the conductive member.

  In the conductive member with a reduced diameter of the superconducting conductor, if there is a protruding non-pressing portion as described above, the conductive member cannot be fitted into the groove formed in the connection body as described above. In some cases, it may be difficult to connect the superconducting conductors via the connection body.

  Therefore, as described above, by using a predetermined rotation mechanism, the plurality of molds are rotated at a predetermined angle around the conductive member at a predetermined angle to reduce the diameter of the plurality of molds of the conductive member. The formation of the non-pressing portion can be suppressed by pressing the non-pressing portion caused by the gap generated between the adjacent forming dies with the pressing surfaces of the plurality of forming dies. As a result, the above-mentioned disadvantage can be suppressed.

  Further, in an example of the present invention, the diameter reducing step may be performed such that at least a part of the plurality of molding dies overlaps the previously reduced diameter portion of the conductive member so that the plurality of molding dies are in a predetermined axial direction. Using the moving mechanism, the conductive member can be moved in the axial direction, and the conductive member can be continuously reduced in diameter in the axial direction of the conductive member by a plurality of molds.

  That is, when moving a plurality of molds, because at least a part of the plurality of molds overlap with the portion of the conductive member having a reduced diameter, the conductive member is long, Even when a long diameter reduction is performed on the conductive member, it is possible to suppress the occurrence of a step between the previously reduced diameter portion and the continuously reduced diameter portion. Can be fitted into the groove of the connection body. Therefore, the above-described diameter-reducing operation can be performed also on a long conductive member, and the electrical and mechanical connection between the superconducting conductors having such a long conductive member is connected to the connection body. It will be possible to perform well through.

  Furthermore, in an example of the present invention, in the arrangement step, a plurality of molds are arranged at equal intervals around the conductive member, and in the diameter reduction step, the plurality of molds are held at an equal interval arrangement, The conductive member can be pressed by the pressing surfaces of a plurality of molds to reduce the diameter. In this case, as described above, when the conductive member is reduced in diameter a plurality of times, the arrangement of a plurality of molding dies for each diameter reduction can be easily determined, and the diameter reduction over a plurality of times can be performed. Can be implemented efficiently. In particular, in the above-described example, the non-pressing portion caused by the gap generated between the adjacent molds of the plurality of molds is rotated by a predetermined angle, and the non-pressing portion is pressed again by their pressing surfaces. In the operation of suppressing the formation of the part, the arrangement of the plurality of molds can be easily determined. Further, the diameter of the superconducting conductor can be reduced in a state where the superconducting wire bundle is focused in the center without being deviated.

  In one example of the present invention, the plurality of molds are a first plurality of molds and a second plurality of molds, and the first plurality of molds are recessed in an arc shape with a first curvature. The second plurality of molds has a second pressing surface that is recessed in an arc shape with a second curvature smaller than the first curvature, and the diameter reducing step includes a first pressing surface. After the first diameter reducing step of reducing the diameter by pressing the conductive member with the first pressing surface of one of the plurality of molds, and after the first diameter reducing step, the second of the second plurality of molds A second diameter reducing step of pressing the conductive member with the pressing surface to reduce the diameter can be included.

  In this case, the first diameter reduction process corresponds to a coarse diameter reduction process, and the second diameter reduction process corresponds to a fine diameter reduction process. That is, the diameter of the conductive member is reduced to some extent using the first plurality of molds, and then the conductive member is reduced to the target diameter using the second plurality of molds. Thus, by using two types of molds and reducing the diameter of the conductive member in two stages, even if the diameter of the conductive member is large, the desired diameter can be obtained with high accuracy by the reduced diameter. it can.

  In this example, the first plurality of molds and the second plurality of molds are used to reduce the diameter of the conductive member in two stages, but three or more types of molds are used. It is possible to reduce the diameter of the conductive member in three or more stages.

  In addition, even when the first plurality of molds and the second plurality of molds are used, all of the above-described examples can be applied to the respective molds. Can play.

  In the connection method and connection device of the present invention, the length of one superconducting conductor is several hundred meters, and a plurality of superconductors having such a length are connected to form a superconducting conductor having a length of several thousand meters. It is effective when obtaining.

  As described above, according to the present invention, it is possible to provide a method and an apparatus for connecting superconducting conductors with a simple connection operation while maintaining the resistance of the connecting portion of the superconducting conductors.

It is a block diagram of the superconducting conductor provided for connection of 1st Embodiment. Similarly, it is a block diagram of a superconducting conductor provided for connection in the first embodiment. Similarly, it is a block diagram of a superconducting conductor provided for connection in the first embodiment. It is a perspective view which shows schematic structure of the superconducting conductor connection apparatus used by 1st Embodiment. It is sectional drawing at the time of cutting the connection apparatus shown in FIG. 4 by the plane perpendicular | vertical to a length direction. It is process drawing for demonstrating the connection method of the superconducting conductor in 1st Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 1st Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 1st Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 1st Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 1st Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 1st Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 1st Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 1st Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 1st Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 1st Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 1st Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 1st Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 1st Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 2nd Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 2nd Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 2nd Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 2nd Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 2nd Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 2nd Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 2nd Embodiment. It is process drawing for demonstrating the connection method of the superconducting conductor in 2nd Embodiment.

  The details of the present invention as well as other features and advantages are described below.

(First embodiment)
1 to 3 are configuration diagrams of a superconducting conductor provided for connection in the present embodiment, FIG. 4 is a perspective view illustrating a schematic configuration of a superconducting conductor connecting device used in the present embodiment, and FIG. FIG. 5 is a cross-sectional view of the connection device shown in FIG. 4 taken along a plane perpendicular to the length direction. In all the drawings shown in the embodiments, similar and identical components are denoted by the same reference numerals.

  As shown in FIG. 1, the superconducting conductor 10 in the present embodiment has a plurality of superconducting wires 11 separated in blocks by a stainless steel tape 12, for example, so that a predetermined refrigerant flows in the length direction of the superconducting conductor 10. The channel hole 14 is formed to surround the periphery of the channel hole 14 to form a bundle. The plurality of superconducting wires 11 are covered with a conduit 13.

  Alternatively, as shown in FIG. 2, a superconducting structure in which a plurality of superconducting wires 11 are covered with a conduit 13 without being separated into a block shape by a tape and without having a channel hole for flowing a coolant. It is good also as the conductor 10-1.

  Each of the superconducting wires 11 shown in FIGS. 1 and 2 is obtained by twisting a total of three wires, for example, by twisting one superconducting wire 111 and two copper wires into three further. The twisted wire can be further twisted into three, and the resulting twisted wire can be twisted into two again.

  For example, as shown in FIG. 3, the superconducting wire 111 is coated with a stabilizing copper 111B around the superconducting filament 111A, and a plurality of these are embedded in the copper material 111C, and the surroundings are tubular members such as copper or aluminum. It can be obtained by coating with 111D.

  In the present embodiment, the plurality of superconducting element wires 11 are synonymous with a superconducting element wire bundle. Therefore, in the following, the reference numeral 11 may appropriately mean a single superconducting element wire, or may mean the superconducting element wire bundle.

  In the superconducting conductor 10, the number of superconducting wires 11 is six, but the number can be arbitrarily determined as necessary. Further, the channel hole 14 can be omitted if necessary.

  The superconducting conductor 10 is assumed to be used for a large superconducting coil that mainly generates a high magnetic field such as a fusion device or a superconducting energy storage system device by flowing a coolant through the channel hole 14. 1 assumes the case where it uses mainly for a power transmission line etc. which do not need to flow a refrigerant | coolant. In the connection method and the connection device described below in this embodiment, the length of one superconducting conductor is several hundred meters, and a length of several thousand meters is formed by connecting a plurality of superconductors having such a length. Therefore, it is assumed that the superconducting conductor 10 shown in FIG. 1 is mainly connected. However, the superconducting conductor 10-1 shown in FIG. 2 is not excluded.

  As shown in FIGS. 4 and 5, the connection device 20 used in the present embodiment includes a plurality of molding dies 21, a plurality of hydraulic cylinders 22 provided according to these molding dies 21, and a cylindrical holding member. 23. Each of the plurality of molds 21 has a pressing surface 21 </ b> A that is recessed in a circular arc shape with a predetermined curvature, and is attached to the tip of the corresponding hydraulic cylinder 22. The hydraulic cylinder 22 is fitted into a through hole formed in the side surface of the holding member 23 and is fixed to the holding member 23 via a fixing member such as a screw (not shown). In addition, the holding member 23 is fixed on the support base 25 via the rotating roller 24, and the holding member 23 is rotated in the circumferential direction by the rotating roller 24, thereby connecting the superconducting conductors as shown below. It can be used.

  A flange 231 having flange holes 231A formed at equal intervals is connected to one end surface of the holding member 23 by welding or the like. The flange 231 (flange hole 231A) is used for adjusting the arrangement angle of the plurality of molds 21 in the connection method described below. For example, if twelve flange holes 231A are formed at equal intervals, the angle formed by the adjacent flange holes 231A is 30 degrees. Therefore, the arrangement angle of the plurality of molds 21 can be determined with reference to the angles. it can.

  A hydraulic unit and a hydraulic control device (not shown) are connected to the hydraulic cylinder 22, and an appropriate hydraulic pressure is supplied to the hydraulic cylinder 22 through the hydraulic unit and the hydraulic control device.

  In the present embodiment, the number of molding dies 21 is set to 3, and the number of hydraulic cylinders connected thereto is also set to 3, but these numbers are not particularly limited. However, these numbers are preferably 3 or more. In addition, it is preferable that the conductive members are pressed by the pressing surfaces of the plurality of molding dies in a state where the conductive members described below are arranged at regular intervals around the conductive members and the plurality of molding dies are held at regular intervals. Thereby, the diameter reduction process in the connection method described below can be performed efficiently and effectively. Further, the diameter of the superconducting conductor can be reduced in a state where the superconducting wire bundle is focused in the center without being deviated.

  Next, a method of connecting the superconducting conductors 10 and 10-1 having the configuration shown in FIGS. 1 to 3 when the connecting device 20 shown in FIGS. 4 and 5 is used will be described. 6-18 is a figure for demonstrating the connection method in this embodiment. 7, 8, and 13 to 16 are cross-sectional views of the superconducting conductor used for connection when cut along a plane including the center line in the length direction, and FIGS. FIG. 9 is a cross-sectional view of the superconducting conductor shown in FIG. 8 when cut along a line I-I perpendicular to the length direction including the mold.

  In the present embodiment, as shown in FIGS. 4 and 5, the connection device 20 has three molds, which form an angle of 120 degrees with each other, and are arranged at equal intervals along the side surface of the holding member 23. The case will be described. In the present embodiment, a connection method related to the superconducting conductor 10 will be described. The superconducting conductor 10-1 is the same as the connection method for the superconducting conductor 10 except that the channel hole 14 is not provided.

  First, as shown in FIG. 6, the end of the conduit 13 is removed, and the superconducting element bundle 11 is exposed. At this time, the stainless steel tape 12 exposed on the surface may be removed if necessary, or may be retracted into the conduit 13 if possible. Further, the channel hole 14 in the exposed portion of the superconducting wire bundle 11 is also removed. As a result, in the superconducting element wire bundle 11, a hole portion 14 </ b> A is formed (residual) due to the removal of the channel hole 14. When the superconducting element wire 11 is coated with chromium plating, nickel plating or the like, this coating is removed as appropriate by chemical treatment or mechanical treatment.

  Next, as shown in FIG. 7, the exposed superconducting wire bundle 11 is covered with a conductive member 16. In FIG. 7, the entire exposed superconducting wire bundle 11 is covered with the conductive member 16, but it is sufficient to cover at least the end portion that contributes to the connection between the superconducting conductors described below.

  Next, the superconducting conductor 10 in the state shown in FIG. 7 is disposed in the holding member 23 of the connecting device 20 shown in FIGS. 4 and 5 so as to be positioned in the cavity defined by the mold 21. Next, an appropriate hydraulic pressure is supplied to the hydraulic cylinder 22 via a hydraulic unit and a hydraulic control device (not shown), and the conductive member 16, that is, the superconducting conductor 21 is pressed on the pressing surface 21 </ b> A of the molding die 21 as shown in FIG. 8. Press the circumferential surface.

  At this time, since it is difficult to reduce the diameter of the conductive member 16 so as to have a predetermined diameter at a time using the molding die 21, as shown in FIGS. To reduce the diameter. For example, as shown in FIG. 9, first, three molds 21 are used to press a predetermined portion of the conductive member 16 to reduce the diameter. At this time, since the adjacent molding dies 21 are separated from each other without being in close contact with each other, a gap is formed between the adjacent molding dies 21, and the non-pressing portion 16 </ b> A is formed based on the gap without being pressed. Will be. Although not particularly illustrated, the non-pressing portion 16A is convex with respect to the pressing surface (reduced diameter surface) of the conductive member 16, and is formed as a protrusion.

  When the reduced-diameter conductive member 16 includes the protruding non-pressing portion 16A as described above, the conductive member 16, that is, the superconducting conductor 10 is placed in the groove formed in the connection body as described below. In some cases, the superconducting conductors 10 cannot be connected to each other, and it becomes difficult to connect the superconducting conductors 10 via the connection body.

  Therefore, by rotating the holding member 23 by a predetermined angle using the rotation roller 24 as a rotation mechanism, the three molds 21 are rotated around the conductive member 16 by the same angle, and as shown in FIG. The non-pressing portion 16A caused by the gap generated between the adjacent molds 21 of the diameter conductive member 16 is pressed by the pressing surface 21A of the mold 21 so that the conductive member 16 is the same as the mold 21. If the pressing surface 21A is pressed again, the non-pressing portion 16A can be eliminated. The holding member 23 can be rotated manually or by a motor (not shown) or the like.

  Even in the state shown in FIG. 10, since a gap is formed between the adjacent molds 21, the protruding non-pressing portion 16A is formed again based on this gap. Therefore, also in this case, similarly to the above, by rotating the holding member 23 by a predetermined angle using the rotating roller 24, the three molds 21 are rotated around the conductive member 16 by the same angle, and FIG. As shown, the non-pressing portion 16A due to the gap generated between the adjacent molds 21 of the reduced-diameter conductive member 16 is pressed by the pressing surface 21A of the mold 21 so that the conductive member 16 is Similarly, if the pressing surface 21A of the mold 21 is pressed again, the non-pressing portion 16A can be eliminated.

  After repeating the above operation and reducing the diameter of the conductive member 16, that is, the superconducting conductor 10, while eliminating the non-pressing portion 16A, as shown in FIG. 12, there is a gap between the adjacent molds 21. Press so that it does not occur. In this case, the non-pressing portion 16A due to the gap is not formed, and the adjacent molding dies 21 come into contact with each other, so that the conductive member 16 is pressed with a pressure higher than this. Therefore, the diameter reduction of the conductive member 16, that is, the superconducting conductor 10, is completed.

  9 to 12 is performed after the pressing of the conductive member 16 by the molding die 21 is once released. When the process is shifted in a pressed state, that is, when the mold 21 is rotated by a predetermined angle, a huge external force is required for the rotation of the mold 21, and the conductive surface is formed by the pressing surface 21 </ b> A of the mold 21. Since the surface of 16 will be damaged, there is a case where the connection of the connecting body described later cannot be performed and the superconducting conductors 10 cannot be joined.

  In the present embodiment, since the three molding dies 21 are arranged at equal intervals around the conductive member 16, a plurality of reduced diameters of the conductive member 16 are provided as shown in FIGS. In the case of carrying out divided times, in particular, referring to the flange hole 231A formed in the flange 231 of the holding member 23, it is possible to easily determine the arrangement of the molding die 21 for each reduced diameter in FIGS. The diameter reduction over a plurality of times can be carried out efficiently. Further, the non-pressing portion 16A caused by the gap generated between the adjacent molding dies 21 is rotated by a predetermined angle, and the pressing surface 21A is pressed to extinguish the non-pressing portion 16A. In the operation of reducing the diameter again, the arrangement of the mold 21 can be easily determined.

  As is clear from FIG. 8, generally, the length of the conductive member 16 in the same direction as that of the pressing surface 21 </ b> A in the length direction of the superconducting conductor 10 of the molding die 21 is generally greater. Is getting bigger. Therefore, the operation of reducing the diameter of the conductive member 16 shown in FIGS. 9 to 12 is only performed on the circumferential surface of a specific portion in the length direction of the conductive member 16.

  Therefore, in the present embodiment, the conductive member 16 is sequentially moved in the axial direction, that is, the length direction thereof by an axial movement mechanism (not shown), and the entire length direction of the conductive member 16 is shown in FIGS. 12 is carried out to reduce the overall diameter of the conductive member 16. Such a diameter reduction is performed based on an operation as shown in FIGS.

  First, as shown in FIG. 13, after the diameter reduction is performed by the operation shown in FIGS. 9 to 12, for example, in the portion A in the length direction of the conductive member 16 and close to the conduit 13, The molding die 21 is moved in the length direction of the conductive member 16 so that the diameter-reduced portion A and the next-reduced portion B are partially overlapped, and the operations shown in FIGS. 9 to 12 are performed again. The diameter of the part B is reduced. Subsequently, as shown in FIG. 14, the mold 21 is moved in the length direction of the conductive member 16 so that the reduced diameter portion B and the next diameter reduction portion C partially overlap, and again. The operation as shown in FIGS. 9 to 12 is performed to reduce the diameter of the part C. Similarly, as shown in FIG. 15, the molding die 21 is moved in the length direction of the conductive member 16 so that the portion C having a reduced diameter and the portion D to be reduced next overlap partially, and again. The operation as shown in FIGS. 9 to 12 is performed to reduce the diameter of the part D.

  By repeating the above operation, the diameter of the conductive member 16 can be reduced over the entire length direction, and the superconducting conductor 10 formed by reducing the diameter of the conductive member 16 as shown in FIG. Get.

  As apparent from FIGS. 13 to 16, the hole 14 </ b> A is crushed by the pressing of the mold 21 and disappears at the portion where the diameter reduction has been completed.

  Next, as shown in FIG. 17, a connection body 31 made of a conductive material is prepared, and the shrinkage of the superconducting conductor 10 in which the conductive member 16 as shown in FIG. The conductive member 16 having a reduced diameter of the same superconducting conductor 10 manufactured in the same manner is fitted into the other groove 31A. As a result, the two superconducting conductors 10 are electrically and mechanically connected by the connection body 31.

  In the present embodiment, the groove portions 32A and 33A are provided at corresponding portions of the groove portion 31A so that the superconducting conductor 10 fitted with the conductive member 16 having a reduced diameter in the groove portion 31A is not detached from the groove portion 31A. The upper mold 32 and the lower mold 33 thus prepared are prepared, and the conductive member 16 of the superconducting conductor 10 is divided into the groove 31A of the connection body 31, the groove 32A of the upper mold 32, and the groove 33A of the lower mold 33. It is pinched and fastened. In this case, if the upper mold 32 and the lower mold 33 are also made of a conductive material, electrical connection between the superconducting conductors 10 can be realized in a better state.

  As described above, the portion of the superconducting wire bundle 11 in the superconducting conductor 10 that is exposed from the conduit end 13 is covered with the conductive member 16, and then the conductive member 16 is spaced apart at a predetermined interval in the circumferential direction. The pressure is reduced by a plurality of (three) molding dies 21 having a pressing surface 21A that is recessed in an arc shape, that is, a rounded pressing surface 21A. Therefore, gaps between the plurality of superconducting wires 111 constituting the superconducting wire 11 exposed from the conduit 13 can be reduced, and the resistance of the superconducting wire 11 can be reduced. That is, the resistance of the superconducting wire bundle 11 used for connection of the superconducting conductor 10 can be reduced.

  In addition, since the diameter of the superconducting element wires 11 exposed from the conduit 13 is reduced at a time, not for each element line, the process of reducing the resistance accompanying the diameter reduction can be simplified.

  Furthermore, the superconducting conductor 10 is connected to the conductive connecting member 31 by forming the conductive member 16 having a reduced diameter covering the superconducting wire bundle 11 after reducing the resistance of the superconducting conductor 10 as described above. In addition, the conductive member 16 having a reduced diameter of another superconducting conductor 10 formed in the same manner is fitted into the groove 31A formed in the connection body 31 and the connection body 31 is interposed. To connect indirectly. Therefore, the superconducting conductors 10 can be joined very easily.

(Second Embodiment)
19 to 26 are diagrams for explaining a method of connecting superconducting conductors in the present embodiment. The configuration of the superconducting conductor provided for connection is the same as that shown in FIGS. The configuration of the apparatus used for connection is basically the same as that of the apparatus shown in FIGS. 4 and 5, but the size and shape of the mold are different.

  That is, in the first embodiment, the diameter of the conductive member 16 of the superconducting conductor 10 is reduced by using one type of mold having a pressing surface recessed in an arc shape with a predetermined curvature. Then, compared with the mold used in the first embodiment, the diameter of the conductive member 16 of the superconducting conductor 10 is reduced by additionally using another type of mold having a pressing surface recessed in an arc shape with a smaller curvature. Do. In other words, after reducing the diameter of the conductive member 16 of the superconducting conductor 10 with a forming die having a pressing surface recessed in an arc shape having a large curvature, as described in the first embodiment. The diameter of the superconducting conductor 10 is reduced again with another type of mold having a pressing surface recessed in an arc shape with a smaller curvature.

  In this case, the diameter reduction performed in the first embodiment corresponds to a rough diameter reduction, and the diameter reduction performed in this embodiment corresponds to a fine diameter reduction. That is, the diameter of the conductive member is reduced to some extent using the first plurality of molds, and then the conductive member is reduced to the target diameter using the second plurality of molds. Thus, by using two types of molds and reducing the diameter of the conductive member in two stages, even if the diameter of the conductive member is large, the desired diameter can be obtained with high accuracy by the reduced diameter. it can.

  In the present embodiment, as described above, the three molding dies 41 having the pressing surface 41A that is recessed in an arc shape with a curvature smaller than the curvature of the pressing surface 21A of the molding die 21 used in the first embodiment are provided. A case will be described in which they form an angle of 120 degrees with each other and are arranged at equal intervals along the side surface of the holding member 23 to reduce the diameter.

  First, the steps shown in FIGS. 6 to 16 in the first embodiment are performed, and the narrowed hole 14B remains without completely annihilating the hole 14A after removing the channel hole 14. In this way, the coarse diameter reduction of the conductive member 16 of the superconducting conductor 10 is performed.

  Next, as shown in FIGS. 19 and 20 to 23, the diameter of the conductive member 16 roughly reduced in diameter is reduced in the circumferential direction of a specific portion in the length direction. This step is basically performed in the same manner as the steps shown in FIGS. 8 and 9 to 12 in the first embodiment. That is, the conductive member 16, that is, the superconducting conductor 10 is reduced in diameter so as to have a predetermined diameter at once using the molding die 41 having the arc-shaped pressing surface 41 </ b> A that is recessed with a smaller curvature than the molding die 21. Therefore, as shown in FIGS. 20 to 23, the diameter is reduced in multiple times.

  At this time, as shown in FIG. 20, when the predetermined portion of the conductive member 16 is pressed and reduced in diameter using the three molds 41, the adjacent molds 41 are separated from each other without being in close contact with each other. Therefore, a gap is generated between the adjacent molding dies 41, and the non-pressing portion 16 </ b> B is formed based on the gap without being pressed. Therefore, as shown in FIGS. 21 and 22, the three molding dies 21 are formed around the conductive member 16 by rotating the holding member 23 by a predetermined angle using the rotating roller 24 shown in FIGS. 4 and 5. The diameter is reduced while the non-pressing portion 16B caused by the gap generated between the adjacent molding dies 41 is sequentially disappeared by sequentially rotating by a predetermined angle.

  Next, as shown in FIG. 23, pressing is performed so that no gap is formed between adjacent molds 41. In this case, the non-pressing portion 16B due to the gap is not formed, and the adjacent molding dies 41 come into contact with each other, so that the conductive member 16 is pressed with a pressure higher than this. Therefore, the diameter reduction of the conductive member 16, that is, the superconducting conductor 10, is completed.

  20 to 23 is performed after the pressing of the conductive member 16 by the molding die 41 is once released.

  Also in this embodiment, since the three molds 41 are arranged at equal intervals around the conductive member 16, a plurality of reduced diameters of the conductive member 16 are provided as shown in FIGS. In the case of carrying out divided times, particularly referring to the flange hole 231A formed in the flange 231 of the holding member 23, it is possible to easily determine the arrangement of the forming die 41 for each reduced diameter in FIGS. The diameter reduction over a plurality of times can be carried out efficiently. Further, the non-pressing portion 16B caused by the gap generated between the adjacent molding dies 41 is rotated by a predetermined angle, and the pressing surface 41A is pressed to eliminate the non-pressing portion 16B. In the operation of reducing the diameter again, the arrangement of the mold 41 can be easily determined.

  Next, in accordance with the steps shown in FIGS. 24 to 26, the diameter of the conductive member 16 is reduced in the axial direction, that is, in the length direction. This diameter reduction can be performed in the same manner as the steps shown in FIGS. 13 to 15 in the first embodiment.

  First, as shown in FIG. 24, in the portion A ′ in the length direction of the conductive member 16 and close to the conduit 13, for example, after performing the diameter reduction by an operation as shown in FIGS. 20 to 23, The mold 41 is moved in the length direction of the conductive member 16 so that the part A ′ having a reduced diameter partially overlaps the part B ′ to be reduced next, and again shown in FIGS. Then, as shown in FIG. 25 and FIG. 26, the mold 41 is made conductive so that the part B ′ having a reduced diameter and the part C ′ to be reduced next overlap partially. The member 16 is moved in the length direction and the operation as shown in FIGS. 20 to 23 is performed again so that the reduced diameter portion C ′ and the next reduced diameter portion D ′ partially overlap each other. The mold 41 is moved in the length direction of the conductive member 16, and the operation as shown in FIGS. Performed, performing diameter reduction portion D '.

  By repeating the above operation, the diameter of the conductive member 16 can be reduced over the entire length direction, and the superconducting conductor 10 formed by reducing the diameter of the conductive member 16 as shown in FIG. Get.

  Next, similarly to the first embodiment, as shown in FIG. 17, a connection body 31 made of a conductive material is prepared, and the conductive member 16 as shown in FIG. The reduced-diameter conductive member 16 of the superconductor 10 thus formed is fitted, and the reduced-diameter conductive member 16 of the same superconductor 10 manufactured in the same manner is fitted into the other groove 31A. . Thus, the two superconducting conductors 10 are electrically and mechanically connected by the connection body 31.

  Further, if necessary, groove portions 32A and 33A are provided at corresponding portions of the groove portion 31A so that the superconducting conductor 10 fitted with the conductive member 16 having a reduced diameter in the groove portion 31A is not detached from the groove portion 31A. The upper mold 32 and the lower mold 33 thus prepared are prepared, and the conductive member 16 of the superconducting conductor 10 is divided into the groove 31A of the connection body 31, the groove 32A of the upper mold 32, and the groove 33A of the lower mold 33. It can also be clamped and fastened.

  Therefore, in this embodiment, in addition to being able to achieve the same operational effects as those of the first embodiment, by using two types of molds and reducing the diameter of the conductive member in two stages, it is possible to conduct electricity. Even if the diameter of the conductive member is large, the effect of being able to obtain the target diameter with high accuracy by reducing the diameter can be obtained.

  In the present embodiment, the two types of molding dies 21 and 41 having different curvatures of the pressing surface are used to reduce the diameter of the conductive member 16 in two stages, but there are three or more types of molding dies. The diameter of the conductive member 16 can be reduced in three or more stages.

The present invention has been described in detail based on the above specific examples. However, the present invention is not limited to the above specific examples, and various modifications and changes can be made without departing from the scope of the present invention.

10, 10-1 Superconducting conductor 11 Superconducting wire (superconducting wire bundle)
12 Stainless steel tape 13 Conduit 14 Channel hole 16 Conductive member 20 Superconducting conductor connection device 21, 41 Mold 21A, 41A Press surface 22 Hydraulic cylinder 23 Holding member 24 Rotating roller 25 Support base 31 Connection body 31A Groove 32 Upper mold 33 Lower mold

Claims (20)

In the method of connecting a superconducting conductor in which a superconducting wire bundle in which a channel of a refrigerant passage is formed in the center is accommodated in a conduit,
A covering step of covering a portion of the superconducting wire bundle exposed from the conduit end with a conductive member in a state lacking the channel;
A plurality of molds having pressing surfaces recessed in an arc shape with a predetermined curvature are provided at predetermined intervals in the circumferential direction of the conductive member, and the conductive material is contained in a cavity formed by the plurality of molds. An arrangement step of arranging a sex member;
A diameter reducing step of reducing the diameter by pressing the conductive member with the pressing surfaces of the plurality of molds;
The reduced-diameter conductive member and the reduced-diameter conductive member that covers the periphery of the superconducting wire bundle of another superconductor formed in the above process are fitted into the groove formed in the conductive connector. A joining step of electrically and mechanically joining,
A method for connecting a superconducting conductor, comprising: A covering step of covering a portion exposed from the conduit end of the superconducting wire bundle in the superconducting conductor with a conductive member;
A plurality of molds having pressing surfaces recessed in an arc shape with a predetermined curvature are provided at predetermined intervals in the circumferential direction of the conductive member, and the conductive material is contained in a cavity formed by the plurality of molds. An arrangement step of arranging a sex member;
A diameter reducing step of reducing the diameter by pressing the conductive member with the pressing surfaces of the plurality of molds;
The reduced-diameter conductive member and the reduced-diameter conductive member that covers the periphery of the superconducting wire bundle of another superconductor formed in the above process are fitted into the groove formed in the conductive connector. A joining step of electrically and mechanically joining,
A method for connecting a superconducting conductor, comprising:   In the diameter reduction step, the plurality of molds are rotated at a predetermined angle around the conductive member at a predetermined angle to reduce the diameter between the adjacent molds of the plurality of molds. The method for connecting a superconducting conductor according to claim 1, further comprising a step of pressing a non-pressing portion caused by a gap generated in the step with the pressing surfaces of the plurality of molding dies.   In the diameter reducing step, the plurality of molds are moved in the axial direction of the conductive member such that at least a part of the plurality of molds overlaps a portion of the conductive member having a reduced diameter. The superconductivity according to any one of claims 1 to 3, further comprising a step of continuously reducing the diameter of the conductive member by the plurality of molds in the axial direction of the conductive member. Conductor connection method.   In the arranging step, the plurality of forming dies are arranged at equal intervals around the conductive member, and in the diameter reducing step, the plurality of forming dies are held in a state in which the plurality of forming dies are held at equal intervals. The method for connecting a superconducting conductor according to claim 1, wherein the diameter of the conductive member is reduced by pressing the conductive member with the pressing surface of the mold. The plurality of forming dies are a first plurality of forming dies and a second plurality of forming dies, and the first plurality of forming dies have a first pressing surface recessed in an arc shape with a first curvature. And the second plurality of molds have a second pressing surface that is recessed in an arc shape with a second curvature smaller than the first curvature,
The diameter reduction step includes a first diameter reduction step of reducing the diameter by pressing the conductive member with the first pressing surface of the first plurality of molds, and after the first diameter reduction step. 3. The method according to claim 1, further comprising a second diameter reducing step of reducing the diameter by pressing the conductive member with the second pressing surface of the second plurality of molds. Superconducting conductor connection method.   In the first diameter reducing step, the first plurality of molds are rotated at a predetermined angle around the conductive member at least once by a predetermined angle to reduce the diameter of the first plurality of conductive members. 7. The method includes a step of pressing a non-pressing portion caused by a gap generated between adjacent molding dies of the first molding die with the first pressing surfaces of the first plurality of molding dies. The connection method of the superconducting conductor as described in 2.   In the first diameter reducing step, at least a part of the first plurality of molds overlaps with a portion of the conductive member that has been reduced in diameter so that the first plurality of molds are The method includes a step of continuously moving in the axial direction of the conductive member by moving in the axial direction of the conductive member and continuously reducing the diameter of the conductive member by the first plurality of molds. Item 8. The superconducting conductor connection method according to Item 6 or 7.   In the second diameter reducing step, the second plurality of molds are rotated at a predetermined angle around the conductive member by a predetermined angle to reduce the diameter of the second plurality of conductive members. The method further comprises a step of pressing a non-pressing portion caused by a gap generated between adjacent molds of the molds with the second pressing surfaces of the second plurality of molds. The connection method of the superconducting conductor as described in any one of -8.   In the second diameter reducing step, at least a part of the second plurality of molds overlaps with a portion of the conductive member that has been reduced in diameter, so that the second plurality of molds are The method includes a step of moving in the axial direction of the conductive member and continuously reducing the diameter of the conductive member by the second plurality of molds in the axial direction of the conductive member. Item 10. The method for connecting a superconducting conductor according to any one of Items 6 to 9.   In the arranging step, the first plurality of molding dies are arranged at equal intervals around the conductive member, and in the first diameter reducing step, the equally spaced arrangement of the plurality of molding dies is maintained. The superconducting conductor according to any one of claims 6 to 10, wherein the diameter of the conductive member is reduced by pressing the conductive member with the first pressing surface of the first plurality of molds. Connection method.   In the arranging step, the second plurality of molding dies are arranged at equal intervals around the conductive member, and in the second diameter reducing step, the equally spaced arrangement of the plurality of molding dies is maintained. The superconducting conductor according to claim 6, wherein the diameter of the conductive member is reduced by pressing the conductive member with the second pressing surface of the second plurality of molds. Connection method. The superconducting conductor bundle in the superconducting conductor has a pressing surface that is spaced apart at a predetermined interval in the circumferential direction of the conductive member that covers the portion exposed from the end of the conduit, and is recessed in an arc with a predetermined curvature. A plurality of molds for reducing the diameter of the conductive member;
Pressure supply means for applying a pressing force for reducing the diameter of the conductive member with respect to the plurality of molds;
A cylindrical holding member that holds the plurality of molds and the pressure supply means;
A connection device for a superconducting conductor, comprising:   14. The superconducting conductor connection device according to claim 13, further comprising a rotation mechanism for rotating the plurality of molds at a predetermined angle around the conductive member at least once.   Axial movement for moving the plurality of molds in the axial direction of the conductive member such that at least a part of the plurality of molds overlaps a portion of the conductive member having a reduced diameter. 15. The superconducting conductor connecting device according to claim 13, further comprising a mechanism.   The plurality of forming dies are a first plurality of forming dies and a second plurality of forming dies, and the first plurality of forming dies have a first pressing surface recessed in an arc shape with a first curvature. The second plurality of molds has a second pressing surface that is recessed in an arc shape with a second curvature smaller than the first curvature. Superconducting conductor connection device.   The superconducting conductor connection device according to claim 16, wherein the rotating mechanism rotates the first plurality of molding dies at a predetermined angle at least once around the conductive member.   The superconducting conductor connection device according to claim 16 or 17, wherein the rotating mechanism rotates the second plurality of molding dies at a predetermined angle around the conductive member at least once. .   The axial movement mechanism is configured such that at least a part of the first plurality of molding dies overlaps a portion of the conductive member having a reduced diameter before the first plurality of molding dies. The superconducting conductor connecting device according to any one of claims 16 to 18, wherein the connecting member is moved in an axial direction of the member.   The axial direction moving mechanism is configured such that at least a part of the second plurality of molding dies overlaps a portion of the conductive member that has a reduced diameter before the second plurality of molding dies. The superconducting conductor connecting device according to any one of claims 16 to 19, wherein the superconducting conductor is moved in an axial direction of the member.

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