JPS59150487A - Current leading device of cryogenic temperature - Google Patents

Abstract

PURPOSE:To reduce the amount of heat invaded to a superconductive device and then make the titled device compact with the large cooling action of the conduction part by a method wherein a plurality of electric good conductor disks having many small holes are laminated by providing gaps in the conduction part and then connected in series. CONSTITUTION:The current passage of the conduction part between current terminals 3 and 9 flows radially through the disks 6 between circular rings 7 and small diameter disks 8, and the disks 6 are cooled by helium gas 13 passing through the small holes 6a. The length of the current passage can be freely selected by the number of pieces of the product of those of the disks 6 and the circular rings 7, the small diameter disks 8, and the whole length of the conduction part is short. The conduction cross sectional area of the conduction part can be selected by the diameter and thickness of said disks 6, rings 7, and disks 8, thus enabling to obtain a conduction part of a high cooling efficiency. The thermal conductivity when gas passes through short holes is very large in the neighborhood of starting the approach run section of thermal conduction, and said section is formed in every disk 6, accordingly high thermal conductive characteristics can be obtained as a whole.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a cryogenic current lead device for introducing current into a superconducting device or the like.

[Technical background of the invention and its problems]

In a superconducting device, a superconducting magnet is housed in a cryogenic storage vessel and cooled with liquid helium.Liquid helium has a very small latent heat of vaporization, so in order to reduce evaporation loss, it has a vacuum-insulated structure with less conductive heat. There is. The current introduction part for exciting the superconducting magnet needs to have a sufficient area to pass the necessary ft current, and since it is a good conductor, it becomes a good heat conductor and becomes a large heat infiltration path.

Therefore, in order to reduce the heat intrusion, cryogenic current lead devices have been widely used which cool the lead part with evaporated helium gas from liquid helium. In other words, cryogenic current lead devices use a structure in which the conductive part is lengthened to increase the cooling surface area in order to improve heat exchange and reduce conductive heat. For example, there is one in which the conductive part is a thin copper wire and a partition plate is provided between the room temperature part and the liquid helium temperature part so that the helium gas passes in a zigzag manner.

However, with such a structure, as the current value increases, the number of thin copper wires increases, requiring a great deal of labor to manufacture, and the cross-sectional area of the copper increases, making heat conduction poor, so the thin wires must be made longer. Must be. On the other hand, at the low-temperature end of the conductive part, the electrical resistance of the steel is a few tenths of the same as that at the room-temperature part, so a good current lead device can be obtained by reducing the current-carrying cross-sectional area of this part and reducing the heat conduction. The conventional conductive part integrated type had drawbacks such as that it was not easy to reduce the cross-sectional area at the low temperature end.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a low-temperature current lead device in which the cooling effect of the conductive portion reduces the amount of heat that enters the ultra-high conductivity device and is compact.

[Summary of the invention]

In order to achieve the above object, the present invention provides a cryogenic current lead in which the conductive part is constructed by stacking a plurality of discs of good conductor having a large number of holes with a gap and connecting them in series. Provide equipment.

[Embodiments of the invention]

An embodiment (C) of the present invention 1314 shown in the drawings will be explained in detail below. 2) is l
'l low + i! Pass through the valley device (1) and attach one end to the ultra-low-temperature device fl.
) inside! Outward-facing cylindrical stainless steel sub-plates, etc.
(3) is a DC terminal made of electrically conductive material such as steel or aluminum that penetrates from the chamber (l'IA part 71) into the outer cylinder (2) through the electrically insulating bushing (4). 5) is the outer cylinder (
Circle i"i tangent to P co 1liIl of II; 1-shaped +i
As shown in Figure 6, it is a gas conductor plate with a large number of small holes (6a), and a number of discs (6) are placed in the gap. Set up a multiplication disk (
During step 6), the ring (7) and the small-diameter disk (8) of the Mn body are solidified by brazing or the like, and connected in series to form a conductive part, and then attached to the lining (5). Contact HL, I'm here. (9)
1 on the low-temperature side is connected to the liquid lium (11) in the cryogenic temperature ig = (i) using a fluidizer, The other end is a disk (9a) with many small holes, and the #- conductive part is attached between the other end of the terminal (3) and the disk (3a) with many small holes. ing. (IJ is a helium gas outlet pipe provided at the upper part of the outward facing part (2), and 131 is a small hole in the guide part (6).
6a) and is discharged from the outlet tube housing.

Next, the action will be explained. Current terminal (3) and current terminal (9)
The current path of the conductive part between the disk (6) and the small diameter disk (8) flows radially between the disk (6) (It is cooled at step 13. The length of the current path can be freely selected depending on the number of laminated disks (6), rings (7), and small diameter disks (8), and the length of the entire conductive part is short. The area of the conductive part is a circular plate (6
), the ring (7), and the diameter and thickness of the small-diameter disk (8) can be selected, making it possible to obtain a quadrielectric part with high cooling efficiency. Moreover, excellent cooling characteristics can be obtained by selecting the size and number of the small holes (6a). The reason is that the heat transfer coefficient □ when gas passes through a short hole is very large near the start point of the heat transfer run-up section, and the disc (
This is because a run-up section is formed for each 6), and high heat transfer characteristics are obtained as a whole.O Figure 3 shows another embodiment, and the difference from Figure 1 is that there are many small holes (6a). and a disc (6) having a cutout (6b) and a hole (14a) larger than the large number of small holes (6a).
and insulating disks I of electric insulators having cutout portions (14b) are stacked alternately, and conductive pieces (151) are arranged in a spiral shape and brazed between adjacent disks (6). The connection points of the conductive piece (151) are the connection points (6c) on the front and back sides of both ends of the cutout (6b) of the disc (6).
) and (6d) are arranged alternately. Current is introduced into the connection (6c), flows circumferentially around the disk (6), and rises from the connection (6d) to the adjacent disk (6).

At this time, helium gas 0'5 enters the small hole (6a) of the disk (6).
The disk (6) is cooled through a cooling passage between the hole (14a) and the hole (14a) of the insulating disk I. Note that the insulating disc (14) has a hole (14a
) and a disc (6) to reduce heat conduction as much as possible.
It is also possible to adopt a structure that reduces the contact area with.

The current flows spirally through the disc (6) and the conductive piece (2), and is sufficiently cooled by helium gas Oal passing through the small holes (6a) while flowing through the stacked discs (6). High heat transfer characteristics can be obtained by adjusting the size, thickness, and number of laminated layers of the disk (6) and the conductive Katazumi Q. In particular, the mechanical structure of the conductive part is particularly effective against electromagnetic force, etc.・Also, by arranging the conductive pieces (c) to make the conductive paths spiral in opposite directions to cancel the magnetic field generated by the electric current, the inductance of the 4th section can be reduced. Therefore, the excitation d source of the super d-conducting coil can be made small.

In addition, in both of the above embodiments, the disk (6), the ring (n), the small diameter disk (8), the insulating disk u4), the 4-electrode plate 9, etc. are designed to prevent clogging of the small hole (6a) after lamination. The light applied can be manufactured by soldering all at once, and each part is easy to standardize and standardize.

〔Effect of the invention〕

As detailed above, according to the present invention, 11) a current lead device with a high cooling effect can be obtained, and the amount of heat entering the 14-channel lead device can be reduced; (2) The current lead device has been made more compact, and even when the current is input θIL, the amount of heat absorbed does not increase and 'f! 171) It has a compact structure, and the superconducting device can be made more compact.

(3) It is possible to standardize and standardize component parts. (4)・1 Rigidity is low against electromagnetic force and external force. (5) It has excellent effects such as low inductance.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an example of a superconducting current lead device according to the present invention, FIG. 2 is a plan view showing a disk of silk 1, and FIG. 3 is a perspective sectional view showing another example. It is. 2...Outer surface 3,9...Adult terminal 4...
・Butshu 5...Lining 6...Disc
6a...Small hole 6b...Notch 7
...Ring 8...Small diameter disk 14...Insulating plate 14a...Large hole 14b...Notch 15.
・・Conductive Katashiro Keito Patent Attorney Inoue - Male

Claims (1)

[Claims] 1. An outer cylinder that penetrates and is fixed to the cryogenic container, a conductive part that is inserted into the outer cylinder through an insulator, and a cryogenic temperature that cools the conductive part inside the MiJ outer cylinder. In a cryogenic 'E flow lead device consisting of a gas cooling passage, the cutting conductive part is formed of a plurality of 111. A cryogenic 1-flow lead device characterized in that a number of disks of good electrical conductivity are connected in series with a product M t with a gap between them. 2. The cryogenic current REET device according to claim 1, characterized in that rings of good electrical conductivity and small-diameter disks are alternately fixed between the disks. 3. An insulating disc having a large number of holes and notches is inserted between discs having notches, and a conductive piece is fixed between the discs through the notches of the insulating plate. A cryogenic current lead device according to scope 1.