JPS621274B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to cryogenic apparatus, and more particularly to a cryogenic apparatus having improved support for a cryogenic vessel containing superconducting equipment.

In general, a cryogenic apparatus includes a cryogenic container in which superconducting equipment is housed in a vacuum container and necessary equipment in order to prevent heat from entering from the outside.

FIG. 1 shows an outline of a superconducting device having such a configuration. A cryogenic container 2 in which superconducting equipment (not shown) is housed is supported on a base 3 via a support 4, and this base 3 is supported on a pedestal 7 by a support member 5. The cryogenic container 2, the support 4, the base 3, and the supporting member 5 are covered with a vacuum container 1 that can be separated with a predetermined space, and the vacuum container 1 is hermetically fixed to a pedestal 7.

By the way, in cryogenic equipment, an important issue is how to absorb the difference in thermal contraction between devices. In other words, the temperature gradient of the cryogenic device is
Referring to Figure 1, the temperature is cooled and stabilized from the outer wall of the vacuum vessel 1 (marked by C) in the order of room temperature of about 20°C → liquid nitrogen temperature of -196°C (marked by R) → liquid helium temperature of -269°C (marked by A). Ru.

Therefore, there is a large temperature difference of about 215 degrees between the outer wall of the vacuum container 1 (temperature: 20°C) and the base (temperature: liquid nitrogen temperature - 196°C) 3, and naturally there is a difference in thermal contraction between the two. .

The structure that absorbs this difference in heat shrinkage is usually 2
A seed support 4 is provided, and furthermore, the base 3 is fixedly supported by a support member 5 and a plurality of sliding supports are provided.

FIG. 2 shows the conventional fixed support and sliding support states of the base 3 and will be described. Figure 2 uses 6-point support as an example, but one of the 6 support points (Point A) is the fixed point, and the other 5 points (B to F) are the sliding support points. This sliding support part was designed to absorb heat shrinkage.

However, in this method, the fixed support point A
Therefore, the distance to each sliding support point is different.
The amount of thermal contraction (displacement) between AB (AF), AC (AE), and AD also differs. If the distance l between the fixed support point and the plurality of sliding supports differs, the amount of heat shrinkage will also differ, as can be seen from equation (1).

Δl=αl(T ₂ −T ₁ )...(1) Here, Δl=Amount of shrinkage (mm) α=Thermal contraction coefficient (mm/℃) 1=Distance between supporting points (mm) _T1 =Temperature before cooling (℃) T ₂ = Temperature after cooling (℃) For example, assuming that a thermal contraction of Δl occurs between AB (AF), the length between BC (AE) is determined by the Pythagorean theorem, √ between AB Since it is three times as large, the amount of contraction is √3Δl. Furthermore, since the length between AD is twice the length between AB and AB, the amount of contraction is 2Δl.

In this way, when devices placed on a base are supported, the displacement differs depending on each support point, making it difficult to grasp the displacement between devices. A large stress will be generated.

The present invention has been made in view of the above-mentioned points, and its purpose is to prevent stress between devices without varying the displacement of each support point, even if thermal contraction is absorbed. The purpose of the present invention is to provide a cryogenic device that does not require exposure to heat.

In the present invention, a base that supports a cryogenic container in which a superconducting device is housed is fixedly supported at at least one place on a pedestal via a support, and the fixed support part of the support member that is slidably supported at other places is fixedly supported on the base. The intended purpose is achieved by arranging the sliding support part approximately at the center and at a position equidistant from the fixed support part.

The present invention will be described in detail below based on embodiments shown in the drawings. Incidentally, the same reference numerals are used for the same parts as in the past.

FIG. 3 shows a cryogenic apparatus showing an embodiment of the present invention, and since its schematic structure is almost the same as that of a conventional apparatus, detailed explanation will be omitted here.

This embodiment also describes six-point support.

In this embodiment shown in the figure, the base 3 is also fixed and slidably supported, but in this embodiment, this fixed support member 5a is arranged approximately in the center of the base 3, and the other sliding support member 5b is fixed. The base 3 is supported by being arranged at a position equidistant from the support member 5a.

This embodiment will be explained in more detail using FIG. 4. In this embodiment, a fixed support member 5b is provided at the center point G of the six-point support, and as a result, the distances GH, GI, and GJ between the central fixed support member 5b and the six sliding support members 5a are , GK, GL, and GM are all equal.

Therefore, even if a thermal contraction of Δl occurs between GH, since the displacement between the other fixed support member 5a and the sliding support member 5b is the same, the thermal contraction will also be Δl, and there are There is no longer any stress caused by differences in the amount of thermal contraction. Furthermore, it is easy to grasp the displacement between the devices arranged on the base 3 because each support point has the same displacement. Furthermore, if a plurality of sliding support members 5b are to have the same structure, they must be matched to the structure that absorbs the largest amount of heat shrinkage.On the other hand, if each sliding support member 5b is to have the same structure, Although it was necessary to manufacture many different types of members, in this embodiment, the sliding support members 5b may all have the same amount of heat shrinkage, so there is an effect that the sliding support structure can be unified.

Next, the fixed support and sliding support structure of this embodiment will be explained using FIG.

The fixed support member 5a provided at the center point G is the base 3
and the vacuum container stand 7 are fixed with fastening parts 10, and are fitted with a spigot to prevent mutual positional displacement. On the other hand, the plurality of sliding support parts provided at equal distances from point G are composed of a sliding support member 5b, a friction reducing material 8, a fastening part 10, and a spacer 9 for preventing excessive tightening of the fastening part 10. When the base 3 contracts in the direction of the fixed support member 5a, it slides on the sliding surface a. g is a gap provided in advance according to the amount of contraction of the base 3.

Such a sliding structure allows thermal contraction to be absorbed even if it occurs, and no stress is applied between the devices. Incidentally, although the above-mentioned embodiments have been described with respect to thermal contraction, it goes without saying that the same effect can be obtained even if thermal expansion occurs.

According to the cryogenic device of the present invention described above, the base that supports the cryogenic container in which the superconducting equipment is housed via the support is fixedly supported at at least one place on the frame, and the other supports are slidably supported. Since the fixed support part of the member is arranged approximately at the center of the base, and the sliding support part is arranged at a position equidistant from the fixed support part, even if heat shrinkage occurs, each part can be easily removed from the fixed support point. Since the sliding support points are equidistant, the displacement is the same, and stress does not occur between each device, making it very effective for specific cryogenic equipment.

[Brief explanation of the drawing]

Fig. 1 shows a conventional cryogenic device, a front view showing only the vacuum vessel in section, Fig. 2 is a diagram illustrating the support of the base in the conventional case, and Fig. 3 shows an implementation of the cryogenic device of the present invention. FIG. 4 is a diagram illustrating the support of the base in the present invention, and FIG. 5 is an enlarged sectional view of the second part of FIG. 3. DESCRIPTION OF SYMBOLS 1...Vacuum container, 2...Cryogenic container, 3...Base, 4...Support, 5...Support member, 5a...
...Fixed support member, 5b...Sliding support member.

Claims (1)

[Claims] 1. A cryogenic container in which superconducting equipment is housed, a base that supports the cryogenic container via a support,
a plurality of support members that support the base on a pedestal;
A cryogenic apparatus comprising the cryogenic container, a base, and a vacuum container that covers the support member with a predetermined space, the support member fixedly supporting the base at at least one place and slidingly supporting the base at the other places, A cryogenic apparatus characterized in that a fixed support portion of the support member is disposed approximately at the center of the base, and a sliding support portion is disposed at a position equidistant from the fixed support portion.