JPS5898992A - Superconductive device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a superconducting device, such as a superconducting magnet, in which it is necessary to energize a superconducting device from a room temperature region.

In particular, the present invention relates to a superconducting device having a current conducting wire suitable for significantly reducing not only the amount of heat intrusion when energized but also the amount of heat intrusion when not energized.

Fig. 1 shows an example of a conventional superconducting device, where l is a superconducting film, -2 is an inner container that stores liquid helium 3, which is a cryogenic refrigerant for superconducting coils 1, and 4 is an external container for storing liquid helium 3, which is a cryogenic refrigerant for superconducting coils 1. Shield that resists heat penetration, 5
is an outer container that forms a vacuum space for insulation. 6 is a condenser to which refrigerant is supplied from the low temperature generation section, 7 is an exhaust pipe that discharges gas to the outside, and 8 is a superconducting coil l from the normal temperature section.
A current conductor for supplying power to a pair of current conductors,
It is provided in the liquid helium 3, and the amount of gas is adjusted by promoting evaporation by energizing the heater 90. The low-temperature gas regulated in this way is guided to the gas supply pipe 11 through the low-temperature valve IO.

12 and 13 are insulating seals that serve as electrical insulation and cooling gas sealing; 14 is a terminal on the normal temperature side.

15 is a gas exhaust pipe for taking out the cooling gas to the outside.

16.17 has nine valves installed in the pipeline. 18 is a persistent current switch for operating the superconducting coil l in a permanent mode. Figure 2 shows current conduction! ! ! The current conductor 8 is supported in the outer tube 19 by a helical insulating spacer 20, shown in detail in 8 parts. 21 is a cooling pipe, and 22 is an electrical insulator with relatively good thermal conductivity.

23 is a safety valve provided in the gas exhaust pipe 15.

The operating procedure of this superconducting device will be briefly explained.

An injection tube (not shown) is filled with liquid helium. To supply IK current to the superconducting coil, first open the cryogenic valve 10 and valve 16, close the valve 17, and turn the heater 9 on. Guide the regulated low-temperature evaporated helium gas to the gas supply pipe 11, ゛-
The low temperature evaporated helium gas guided to the gas supply pipe 11 is
The nine-spiral spacer 20 placed between the outer tube 19 and the current conductor 80 forms a cold four-stream ayu, and while cooling the current conductor 81c by sensible heat, it reaches the gas joint 15. It is released through 16 tons of squares. Next, the permanent wLR switch 18t is opened, the 'tg terminal 14 on the normal temperature side is connected, and its current is gradually increased. When the predetermined flow rate is reached, the persistent current switch 18t is closed and continuous current mode starts. Then, keep lowering the range award to m flow rate -8 and ending the run with zero. This electric fL
While the 411A 8 is being energized, cooling by the sensible heat of the low-temperature vapor helium gas continues. When there is no longer any need to energize the current conductor 8, the heritum gas in the cooling flow path between the valve 16 and the p gas supply pipe 11. is evacuated to ITorr by an X!2 valve (not shown), and then valve 16 is closed.

fP Transition to steady cooling operation.

In this case, even though the electrical conductor 1vi18 is cooled by cooling agent 9 of the shield 4, such as liquid nitrogen, and through the electrical insulation 221c, the cryogenic valve lO and the valve 16t are closed. 1lL1 of helium gas
%, cooling is stopped and the amount of heat entering the liquid helium due to heat conduction increases. This amount is calculated to be 10 to 30 times the amount when there is gas cooling, so the inner container 2
The increase in the load placed on the chiller AL II machine (not shown) would be a great burden, and it would be a big economic loss.

The object of the present invention is to solve the above-mentioned conventional drawbacks, and to greatly reduce the amount of heat that enters the Uchitani circle not only when energized but also when not energized in persistent current mode.
An object of the present invention is to provide a t-superconducting device.

According to the present invention, the same current conductor as the conventional one is installed on the room temperature side.

On the low temperature side, there is a conductor with relatively low thermal conductivity and a high critical th1
A superconducting wire with integrated thigh 1tii electric wire is conveniently used, and these are connected with a connecting conductor that has good heat exchange with the cooling gas, and a wire mesh is attached to the connecting conductor as a heat converter between this connecting conductor and the cooling gas. Cooling gas 15 by stacking or perforated plates
! 12i', the heat transfer coefficient is set to a large value, and the efficiency of the heat converter is set as t.

Below is 2F - Invention of superconductivity! An example of filling will be explained with reference to FIGS. 3 to 5. FIG. 3 is a detailed view of the Ntlt4 edge portion in this central example. Contents that store cryogenic refrigerant such as liquid helium inside ff, 24 has an outer container 25t - an outside that penetrates '! F26 is provided. Inside this outer tube 26, a current conductor 27 on the normal temperature side, a superconducting wire 28 on the low temperature side, and a connecting conductor 29 made of a material with low electrical resistivity that connects these conductors 27 and 28 are arranged. ing. This superconducting magnet 28 has a high critical temperature like Nb and Sn compound superelectric materials! Tct-high critical temperature superelectric 4
A conductor 28b having a low thermal conductivity such as a copper-tin bronze alloy or the like is constituted by a plurality of rods 281. The total rk1 product of the superconductor 281 is determined by the critical Km! under the operating conditions of the superconductor so that a predetermined % flow rate of current can flow sufficiently. [t-f determined by T c 'lc group
i-9 insulation seal 30. A sub-insulating seal 31 is provided at the upper end to serve as electrical insulation and a cooling gas seal. Insulating spacers 34 and 35 are disposed between the outer tube 26, the current conductor 27 on the normal temperature side, and the superconducting magnetic field 28 on the low temperature side to form electrical insulation and a spiral cooling channel, respectively, on the air defense towers 32 and 33. has been done. The outer tube 26 is separated from the space 33 of the low-temperature side superconductor ff128111 where the connecting conductor side conductor edge 27@9 32 and the insulating spacer 35 are arranged by t''.

Below the outer tube 260 is a cooling gas introduction pipe 37 for introducing low-temperature evaporated helium gas into the interior, and above the cooling gas t.
- A ninth cooling gas exhaust pipe 38 is provided for exhausting from outside the snow. 11F261Z) Inside the outer wax, a refrigerant such as liquid nitrogen is flowed.The cooling F41139 is thermally twisted and the refrigerant flowing inside the cooling pipe 39 has a relatively large heat conduction tube. The hot part of the electric waterfall conductor 111127 on the @ side is cooled via the electric insulator 4Qi.

FIG. 4 is a detailed view of the connection conductor 29 portion in FIG. 3. i! The connecting conductor 29 has a cooling gas flowing through it.
This cooling channel 291 has a cooling channel 291 that communicates with the
There are many fine holes inside, such as thin wire mesh or granular molded metal.
A p-perforated plate made of a large number of laminated heat conductive thin plates and a space! and t-father are piled up in large numbers. Since the heating material 41 has a laminated structure, the efficiency of heat exchange between the connecting conductor 29 and the cooling gas can be greatly increased. 29'b is the connecting conductor 29
High criticality superconductor buried in the lQl wall of 42#
: Temperature needle for monitoring the temperature of the tm connecting conductor 29 [1-.

In the superconducting device configured in this way, the energizing cabinet,
The temperature IIIL of the connecting conductor 29 is cooled to below the critical temperature Tc of the superconductor 28 on the low temperature side by adjusting the amount of cooling gas.

As a result, the superconductor 4 edge 28 on the low temperature side becomes completely superconducting, and the conductor 2
81 p, the Joule heat generation in this part is 4. As a result, the amount of heat that penetrates into the liquid helium during one energization is extremely small.

Next, when electricity is not applied, no cooling gas flows and there is no cooling by sensible heat, so the heat that enters the liquid helium is mostly due to conduction through the conductor. In this case, the superconductor 4m on the low temperature side consists of the conductor 28b and the superconductor 28M, which have a low thermal conductivity [28 has a thermal conductivity of about 1/10 to 1/10 G
Therefore, the aforementioned intrusion heat is also reduced by about 1/10 to 1/100.
It is recognized by its deep roots.

As described above, according to the present invention, heat generation during energization is reduced,
Not only can the amount of heat intruding into the liquid edge 9m be reduced, but also the amount of heat invading by conduction when electricity is not applied can be significantly reduced.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional schematic diagram illustrating an example of a conventional superconducting device;
Figure 2 is a #P detail diagram of the current 4118 part in the g1 diagram.
Fig. 3 is a detailed view of a 1 m1 current conductor portion in the superconducting device of the present invention, and Fig. 4 is a detailed view of a rutted conductor portion in Fig. 3.
iIl#r@ figure. 24...Inner container, 25...Outer container, 26...Outer shrine, 27...Normal temperature 9111 (D current conductor, 28...Low temperature-superconducting wire, 29-@fi conductor, 30.31 .36
-11! L edge seal, 34.35...insulation spacer,
37... Cooling gas introduction pipe, 38... Cooling gas exhaust, 39... Cooling chamber, 41... Heat transfer promoting member. ￥] Figure 1 fJz Mere 3 Figure 111' 33 2 □3qt 32 zB ``Ztb 7 b Rinishi' trap

Claims (1)

[Scope of Claims] 1. An inner container that stores a cryogenic refrigerant, an outer container that uses this inner container to form a vacuum in a space, and a container that houses the cryogenic refrigerant conductive equipment, A superconducting device having a current conductor that connects the current conductor to a power source at room temperature, and a cooling channel that cools the current conductor. A current conductor on the room temperature side, and a superconducting wire on the low temperature side that combines a conductor with low thermal conductivity and an electromotive conductor. A superconducting device comprising a connecting conductor connecting these conductive wires, and a cooling channel having a heat transfer promoting member formed in the connecting conductor. 2. The superconducting device according to claim 11, wherein the heat transfer promoting member is constructed by laminating a large number of heat conductive thin plates having a large number of fine holes.