JPH0325868A - Superconducting wire - Google Patents

Abstract

PURPOSE:To fill a gap in a contact after press fitting, so as to obtain a superconducting wire whose critical current is stabilized at a high value by placing a cushion material between the contact and a clad cylinder. CONSTITUTION:Around a contact 3 for which filaments 2 are twisted with each other and spot-welded, a cushion material 10 is would, after which a clad cylinder 4 is inserted therein, and the contact 3 would with the cushion material 10 is press fitted by a clad golden mold 5, so as to form a first superconducting wire 1a and a second superconducting wire 1b, both of which connected to one another. As the cushion material 10, an indium sheet or a solder sheet, etc. is used. By placing the cushion material between them, pressure given to the filament at the time of press fitting or connecting is mitigated, whereby cutting of the filament does not occur, and high critical current can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a superconducting wire in which first and second superconducting wires each having a filament are connected to each other.

[Conventional technology]

Figure 3 shows an example of a conventional superconducting wire used by B.
a), (lb) are the first and second superconducting wires to be connected to each other, (2) is the filament after removing the stabilizing material, (3> is the first superconducting wire after exposing the filament)
and a connection part where a plurality of filaments (2) of the second superconducting I1 (Ia) and (Ib) are twisted together and spot welded, (4) is used to obtain the mechanical strength of the connection part (3), 2) to firmly tighten the connection part (3).
) is a copper crimp tube that covers the Figures 4A and 4B
The figure shows the crimping cylinder 〈4〉 covered with the connecting part (3) shown in Fig. 3, which has been crimped with the crimping die (5) which is the crimping means. Also, Fig. 5 is a cross-sectional view after the connection part (3> in Fig. 3 is crimped, and (6>) is the crimped fI (4) and filament (
2). Conventional superconducting wires are made by inserting a crimp tube (4) into a joint (3) where multiple filaments (2) are twisted together and spot welded, and then crimped onto the joint (3) using a crimp mold (5). Then, the first superconducting wire (1a) and the second superconducting wire (1b)
It is configured by connecting.

[Problem to be solved by the invention]

In conventional superconducting wires, if the compression ratio by the crimping mold (5) is low, a gap (6) is formed between the filament (2) and the copper tube (4).
), the filament (2) moves and the connection part (
3) There was a problem that variations occurred in the critical current. Furthermore, if the compression ratio of the crimping mold (5) is high, the filament (2) will break and a high critical current cannot be obtained.
) There was also the problem that the crimping conditions had to be controlled very strictly. This invention was made to solve the above-mentioned problems, and it provides a margin for the crimping rate of the crimping mold (5), eliminates voids in the connection part after crimping, and eliminates the filament. The aim is to obtain a superconducting wire that is firmly connected throughout without cutting, and whose critical current is stabilized at a high value. [Means for Solving the Problems] A superconducting wire according to the present invention includes a cushioning material provided on the outer periphery of a connecting portion, and a crimping tube provided on the outer periphery of the cushioning material and crimped together with the connecting portion and the cushioning material. It is something. [Function] In the superconducting wire of the present invention, the cushioning material is interposed between the connecting portion and the crimping portion, so that the connecting portion, the crimping tube, and the cushioning material are crimped by the crimping means and are connected to the first superconducting wire. When the second superconducting wire is connected, a pressure equal to Wl is applied to the filament, and no gap is created between the connection part and the crimping tube after crimping. [Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

FIGS. 1A and 1B show an embodiment of the present invention, and the same or corresponding parts as in FIGS. 3 to 5 are designated by the same reference numerals, and the explanation thereof will be omitted.

In the figure, (IO) is a cushioning material made of very soft and highly conductive indium sheet interposed between the connection part (3) and the crimp tube (4). Cushioning material (10) is wound around the joint (3) where the filaments (2) are twisted together and spot welded, and then the crimp tube (4) is inserted, and then the cushioning material ('0) is wrapped around the connection. The part (3) is crimped with a crimping die (5) to form the first superconducting wire (1a) and the second superconducting wire (1a).
It is omitted by connecting it with b). Figure 2 shows the connection part (3
) after crimping. In the above embodiment, the crimping cylinder (4) was made of copper, but it may be made of soft material with good crimping properties, such as aluminum. Also, cushion material (10)
Although indium sheet was used as the material, it is of course possible to use a soft and conductive material such as solder sheet. Furthermore, in the above embodiment, superconducting wires (
Although la) and (lb) are shown connected to each other in a parallel stacked state, the present invention is not limited to this, and it goes without saying that the present invention can also be applied to cases in which superconducting wires are connected in a straight line.

〔Effect of the invention〕

As explained above, in the superconducting wire of the present invention, a cushioning material is interposed between the connecting portion and the crimping tube, and the connecting portion, the crimping tube, and the cushioning material are crimped to form a first superconducting wire and a second superconducting wire. The effect is that the pressure applied to the filament during crimping and connection is relaxed, the filament does not break, and a high critical current can be obtained. In addition, since there are no gaps in the connection after crimping, there is no minute movement of the filament, and as a result, a stable critical current can be obtained.

[Brief explanation of drawings]

FIG. IA is a partial side sectional view showing an embodiment of the present invention, FIG. IB is a front sectional view of FIG. IA, and FIG. 2 is a front sectional view of the superconducting wire after the superconducting wire of FIG. 1 is crimped. Figure 3 is a partial side sectional view showing a conventional superconducting wire in the middle of connection, Figure 4A is a surface view showing the state in which the superconducting wire in Figure 3 is crimped with a crimping die, and Figure 4B is a 4A is a front sectional view, and FIG. 5 is a sectional view of the superconducting wire after the superconducting wire of FIG. 3 is crimped. In the figure, Ha) and (lb) are the first and second superconducting wires, (2) is the filament, (3> is the connection part, and (4)
(10) is a crimping tube, and (10) is a cushioning material. In each figure, the same reference numerals indicate the same or equivalent parts. Fig. IA Fig. 2 4 Fig. IB Fig. lb Fig. 3 Fig. 4 All lights 5 Leap d Fig. 4B

Claims (1)

[Claims] First and second superconducting wires having a plurality of filaments, and a highly conductive and flexible cushion provided on the outer periphery of a connecting portion where the first superconducting wire and the second superconducting wire are connected. A superconducting wire comprising a crimping tube provided on the outer periphery of the cushioning material and crimped together with the connecting portion and the cushioning material by crimping means.