JPS6142403B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a superconducting magnet used in a superconducting magnetically levitated vehicle or the like.

In recent years, research and development regarding superconducting magnetic levitation vehicles has shown remarkable progress, and the superconducting electromagnets used therein have continued to be improved in order to meet the strict requirements of greater strength, larger capacity, lighter weight, and smaller size. However, as superconducting electromagnets become more powerful and have a larger capacity, the ampere-turns of superconducting electromagnets are increasing rapidly, and the electromagnetic force is becoming more powerful than we can imagine. For this, for example
When using an 800 KAT racetrack-shaped (elliptic) superconducting coil, an electromagnetic repulsive force of 26 tons/m acts between the opposing long sides of the coil, and the question is how to absorb this repulsive force. Stably fixing the coil has become a major technical issue in the production of superconducting electromagnets. If this coil is not stably fixed, the superconducting electromagnet will no longer be able to maintain its superconducting state, leading to the quench phenomenon.

Here, an example of a currently planned superconducting electromagnet will be described with reference to Figures 1 and 2. In the figure, 1 is an inner tank with a racetrack-like structure and a slightly flat cross section, which is not shown in the figure. It is insulated and stored inside the outer tank using a load support material with low heat transfer, vacuum and special heat insulating material. Further, the upper and lower opposing long sides are connected to each other by a bonding material 2 to prevent deformation. Reference numeral 3 denotes a superconducting coil housed inside the inner tank 1 in an elliptical shape, and this is usually formed into a rigid structure by integrally molding and solidifying it by means such as molding. , such superconducting coils 3 are provided with appropriate intervals in the longitudinal direction.
An insulating plate such as FRP is fitted, and a spacer 5 is placed around the outer periphery of the insulating plate, and the coil 3 is fixedly held in the inner tank 1 by the spacer 5. In addition, inner tank 1
If the spacer 5 etc. are not divided, the superconducting coil 3
Since it is not possible to store the superconducting coil 3, we are considering constructing it by dividing it into two parts vertically or horizontally, and assembling them by covering the superconducting coil 3 and joining them by welding or the like. Further, although not shown in the drawings, it is a matter of course that various equipment, piping, etc. necessary for configuring the superconducting electromagnet are incorporated. As described above, the inner tank 1 is insulated and supported inside the outer tank to suppress the amount of heat intrusion to an extremely low level, and the inner tank 1 is filled with liquid helium, so that the superconducting coil 3
The superconducting state is maintained by cooling the superconductor to an extremely low temperature, and a persistent current is obtained by excitation.
In addition, so that the liquid helium can flow to fill the entire area inside the inner tank 1 during the excitation, and so that the helium gas vaporized by heat penetration can rise.
A hole 6 is formed in the spacer 5.

In the case of a superconducting electromagnet having the above structure, if the spacer 5 does not sufficiently hold the superconducting coil 3 fixedly, the coil 3 may become loose or deformed or moved due to electromagnetic repulsion due to excitation or some kind of vibration. As a result, the superconducting state collapses, leading to a problem of quench development. For this reason, stably fixing the coil is a major technical challenge when manufacturing superconducting electromagnets.

The present invention has been made in view of the above circumstances, and its purpose is to fix a superconducting coil extremely reliably and stably inside the inner tank, completely prevent deformation and movement of the coil, and achieve a very stable high-speed The object of the present invention is to provide a superconducting electromagnet that has excitation ability and is optimal for superconducting magnetic levitation vehicles and the like.

An embodiment of the present invention will be described below with reference to FIGS. 3 and 5. Note that only the main parts are shown here, and the rest are the same as those in FIGS. 1 and 2, so illustrations are omitted for the sake of simplification.

Figure 3 shows the relationship between the superconducting coil insulating plate and the spacer in the same cross section as Figure 2, Figure 4 shows the shape of the insulating plate, and Figure 5 shows pre-compression using a tool to make the spacer and insulating plate stick together. The superconducting coil 3A shown in FIG. Insulating plates 4A, 4B, 4C, and 4D such as FRP are placed around the outer periphery of the insulating plates 4A, 4B, 4C, and 4D, and spacers 5A and 5B that are divided into upper and lower halves are placed around the outer periphery of the superconducting coil 3A. The insulating plate prevents the surface of the superconducting wire from being damaged and short-circuited by direct contact with the superconducting wire, and also has sufficient insulation to prevent short-circuiting when excitation or quenching occurs. I am trying to earn a lot of creepage.

Here, the upper and lower insulating plates 4A and 4B have a cross-sectional shape having flanges 11 and 11 on both sides as shown in FIG. has been done. That is, the inner bottom surface of the groove facing the spacers 5A, 5B is a chevron-shaped surface consisting of a high central portion 9 and tapered surfaces 10, 10 that gradually become lower from there toward both ends. In this way, the insulating plates 4A and 4B have spacers 5A and 5B sandwiched between the flanges 11 and 11 on both sides to prevent displacement, while the insulating plates themselves have a structure that is thick in the center and becomes thinner toward the ends. There is. Spacers 5A and 5B divided into upper and lower halves are provided surrounding the upper and lower insulating plates 4A and 4B and the both side insulating plates 4C and 4D.
A, 7B are provided, and holes 6A, 6 are provided near them.
A is arranged, and holes 6B, 6B are also arranged at both ends, and these grooves and holes form a structure that can be elastically deformed. be combined. The tightening tool 12 that applies pre-compression force to the spacer is made up of upper and lower arch-shaped members 12A, 12B and bolts 13A, 13B that tighten these members, and the upper and lower arch-shaped members 12A, 12B elastically deform the spacers 5A, 5B. Tighten the spacer 5
A and 5B are welded together so that they are completely in close contact with the chevron-shaped bottom surfaces of the insulating plates 4A and 4B. The positions where the upper and lower arch-shaped members 12A, 12B of the tool 12 come into pressure contact with the spacers 5A, 5B are designed to be near both ends of the insulating plates 4A, 4B. A superconducting electromagnet is assembled by covering the outside of the combined spacers 5A and 5B with a two-part inner tank (not shown) and welding them together, and then storing the inner tank with insulation support inside the outer tank. It consists of

To explain the function of the present invention, the holes 6A and 6B of the spacers 5A and 5B are connected to the superconducting coil 3.
In addition to the hole, there is a fairly large groove 7 that serves as a passage for the liquid helium injected into the inner tank to cool A and the gas helium vaporized by the cooling effect.
Since A and 7B are arranged one above the other, the inflow of liquid helium and the outflow of gas helium become smoother.
In addition, the grooves 7 of the spacers 5A and 5B can be used as needed for the inner tank.
If it is divided at the location facing A and 7B, it will be extremely convenient from a functional point of view, as it can also be used as a mounting space for a backing plate.

Here, spacers 5A and 5B of insulating plates 4A and 4B
Since the part in contact with is formed into a chevron-shaped surface, the center part contacts, but there is a slight gap at both ends. By determining this gap based on the amount calculated from the elasticity of the spacers 5A and 5B and the force that applies precompression, the upper and lower arch-shaped members 12A and 12 of the tool 12
When a pressing force is applied to the corners of both ends of the outer periphery of the upper and lower spacers 5A, 5B using B and the bolts 13A, 13B, the spacers 5A, 5B close to the grooves 7A, 7B and the hole 6A.
The spacers 5A, 5 form a fairly strong spring structure that is curved due to elastic deformation at the part connecting the spacers 5A, 5.
The inner circumferential surface of B is curved along the groove-inner mountain-shaped bottom surfaces of the insulating plates 4A and 4B, and comes into close contact. In addition, the pressing force applied by the tightening tool 12 at that time is
If the force is made to be approximately equal to or greater than the electromagnetic force acting on the superconducting coil 3A, even if the electromagnetic force acts on the superconducting coil 3A, there will be no gap between the spacers 5A and 5B, and such precompression force can be reduced. If you weld 8A and 8B with the spacer 5
The superconducting coil 3A is better fixed and held by A and 5B. At this time, the taper angle of the chevron-shaped surfaces of the insulating plates 4A and 4B can be estimated to some extent by calculation, but
In the end, it is necessary to use the values confirmed through experiments, so that the chevron-shaped surfaces of the insulating plates 4A, 4B and the spacers 5A, 5B begin to come into contact at a point where the precompression force is slightly lower than the electromagnetic force. Good results can be obtained. By covering the outer periphery of the spacers 5A and 5B configured in this manner with the inner tank divided into two parts and joining them by tightening and welding, the superconducting coil 3A is kept in an extremely stable state within the inner tank by the spacers 5A and 5B. This completely prevents deformation or movement even when subjected to large electromagnetic force, making it possible to obtain a stable, large-capacity superconducting magnet.

It should be noted that another embodiment of the present invention having the structure shown in FIG. 6 can also achieve the same effect. Although not shown, the inner circumferential surface of this spacer 5C facing the insulating plate is a chevron-shaped surface consisting of a smooth and high central portion 14 and tapered surfaces 15A and 15B that become lower toward both end corners. The bottom surface of the groove on the insulating plate side may be flat, and it is possible to obtain exactly the same effect as in the above embodiment. Further, the tapered surfaces 15A and 15B may be formed of circular arcs, and can be processed extremely easily by NC processing or the like.

In addition, as another embodiment, a two-part spacer 5
Instead of joining A and 5B with weld beads 8A and 8B, the spacers 5A and 5B are stacked on top of each other and given an appropriate precompression force (not shown), then reamed and fixed by pushing in a pin. It is also possible to obtain the same effect as above.

Since the present invention is made as described in detail above, the superconducting coil can be very reliably and stably fixed inside the inner tank with the spacer, and the deformation and movement of the coil that would impede the superconducting state can be completely prevented.
It has extremely stable and high excitation ability, making it ideal for superconducting magnetic levitation vehicles and the like.

[Brief explanation of the drawing]

Figure 1 is a partially sectional side view showing the main structure of the racetrack-shaped inner tank of the currently planned superconducting electromagnet, Figure 2 is an enlarged sectional view taken along the - line in Figure 1, and Figures 3 to 5. The drawings show one embodiment of the present invention, in which Fig. 3 is an explanatory diagram of the relationship between the spacer and the cross section of the superconducting coil, Fig. 4 is a perspective view of the insulating plate, and Fig. 5
The figure is an explanatory diagram showing an example of the use of a tool that applies a precompression force when assembling a spacer, and FIG. 6 is a front view of only one side split spacer showing another embodiment of the present invention. 1... Inner tank, 2... Binding material, 3, 3A... Superconducting coil, 4, 4A, 4B, 4C, 4D... Insulating material, 5, 5A, 5B, 5C... Spacer, 6, 6
A, 6B...hole, 7A, 7B...groove, 8A, 8B
...Welding bead, 9,14...Central part of chevron surface,
10, 15A, 15B... Tapered surfaces on both sides of the chevron-shaped surface, 11... Flange.

Claims (1)

[Claims] 1. In superconducting electromagnets used in superconducting magnetic levitation vehicles, etc., an insulating plate is placed around a superconducting coil that is solidified and fixed using a mold, etc., and each insulating plate is made elastically deformable by a combination of grooves, holes, etc. on the outer periphery of the insulating plate. A spacer with a two-part structure is enclosed, and a chevron-shaped surface is formed on one of the facing surfaces of the insulating plate and the divided spacer, and the center is high and becomes lower toward both corners. A superconducting magnet characterized in that the divided spacers are provided with a precompression force so as to eliminate voids at the corners, and are connected to each other by welding or pins to prevent deformation and movement of the superconducting coil.