JPH066897U - Reinforcement structure for cryogenic vessels - Google Patents

Abstract

(57) [Summary] [Purpose] Effectively reinforce the neck pipe extending from the inner container without breaking the vacuum inside the vacuum container. A neck tube reinforcing structure in a cryostat 10 in which a neck tube 14a extends from a ceiling wall 14c of a liquid helium tank housed in a vacuum vessel and a flange portion 14b at an upper end thereof is joined to a flange portion 21b on the vacuum vessel side. The top wall 1
A female screw member 50 is fixed to the back surface of 4c, a cover plate 54 is put on the flange portion 14b, and both are connected by a connecting shaft 52 inserted into the neck tube 14a. A nut 56 is attached to the threaded portion 52b formed at the upper end of the connecting shaft 52, and the nut 56 is tightened to tighten the female threaded member 50 and the cover plate 54.
A tensile force in the direction of bringing them closer to each other is applied between and.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a structure for reinforcing the neck pipe when carrying a cryogenic container such as a cryostat in which a neck pipe extending from an inner container is joined to an outer vacuum container.

[0002]

[Prior art]

 In recent years, as superconducting magnets have been applied to nuclear magnetic resonance analyzers (hereinafter referred to as NMR devices) and magnetic resonance computer tomography devices for medical diagnosis (MRI devices), etc., the superconducting magnets have been cooled with liquid helium. The development of cryostats and other equipment for this purpose is proceeding rapidly. For example, in Japanese Patent Laid-Open No. 4-29700, a liquid helium tank is housed in a vacuum tank, a helium pipe (neck) is extended upward from the upper wall of the liquid helium tank, and the upper end of the neck is It is shown that the liquid helium tank is suspended and supported in the vacuum tank by joining it to the above vacuum tank by welding or the like.

The above-mentioned neck pipe is for discharging the vaporized helium gas in the liquid helium tank to the atmosphere. To prevent heat invasion by heat conduction using this neck pipe as a medium, the neck pipe has a diameter as small as possible. It has a long shape. Therefore, if the cryostat of this structure is transported without any reinforcement, buckling deformation such as bending of the central part of the neck tube is caused by the vertical vibration during this transportation. May occur and cause damage. For this reason, it is necessary to reinforce the neck pipe during transportation, but if it is necessary to release the vacuum in the vacuum tank in order to reinforce this, sufficient vacuum is not available after the cryostat reaches the destination. It takes a long rise time to form a state, which causes a problem that work efficiency is significantly reduced.

Therefore, the above publication proposes a method of inserting and transporting a rod-shaped or tubular bending prevention member having an outer diameter slightly smaller than the inner diameter of the neck pipe. According to this method, buckling deformation of the neck can be prevented by simply inserting the bending prevention member while maintaining the cryostat vacuum during transportation, while pulling out the bending prevention member after arrival at the destination. It is possible to start using.

[0005]

[Problems to be solved by the device]

 When the cryostat vibrates in the vertical direction during the above transportation, a compressive force due to the acceleration obtained by subtracting the gravitational acceleration from the upward acceleration acts on the neck upward, and the downward acceleration is the acceleration obtained by adding the gravitational acceleration to the downward acceleration. The tensile force due to acts as it is. In particular, when driving on highly uneven roads, such as speed-prevention stepped zones provided at regular intervals or roads with a lot of paving, the compressive force and tensile force due to the acceleration are considerably large. Become.

Of these forces, the buckling deformation due to the upward compression force can be prevented in advance by the above-described bending prevention member, but the downward pulling force acts on the neck tube as it is. Due to this tensile force, a large stress exceeding the allowable stress is generated in the neck tube with a small cross-sectional area, which may cause the neck tube to break.

In view of such circumstances, an object of the present invention is to provide a reinforcing structure capable of more reliably preventing damage to the neck pipe during transportation of a low temperature container without breaking the vacuum in the vacuum container. And

[0008]

[Means for Solving the Problems]

 The present invention has a neck pipe extending upward from the container body, and an inner container for containing a low temperature substance is joined to the upper end of the neck pipe to support the inner container in a suspended state. A cryogenic container including a vacuum container for accommodating a container, comprising a reinforcing member that connects the container body of the inner container and the upper end of the neck pipe in a state of being inserted into the neck pipe (claim 1). ).

As the reinforcing member, at least a container-side member that abuts an upper wall back surface of a container body of the inner container, and a portion of the upper end of the neck pipe and a portion of the vacuum container that is joined to the upper end of the neck pipe. A neck pipe side member that abuts on one side, and a connecting member that is inserted into the neck pipe and connects the container side member and the neck pipe side member while applying a pulling force in a direction to bring them close to each other Is preferred (claim 2).

Further, a main body having a plurality of connecting members, each connecting member having a lower end connected to the container-side member and a threaded portion formed at an upper end, the threaded portion penetrating the neck-side member, The nut is attached to the threaded portion, and is provided with a nut pressure contact member interposed between the lower surface of the nut and the upper surface of the neck pipe side member, and both connecting members are provided on the lower surface of the nut pressure contact member. By arranging a pressure contact part at an intermediate position of the above, and configuring the nut pressure contact part so that the nut pressure contact part can be tilted with the pressure contact position between this pressure contact part and the neck side member as a fulcrum, A more excellent effect can be obtained (claim 3).

[0011]

[Action]

 According to the above configuration, the reinforcing member is inserted into the neck tube, and the container body portion of the inner container and the upper end of the neck tube are connected by this reinforcing member, so that the cross-section integral of the reinforcing member leads to the neck portion. It is possible to increase the substantial cross-sectional area of Therefore, if the cryocontainer is transported in this state, the tensile stress generated due to the tensile force acting downward on the neck tube during this transportation can be reduced by the above-mentioned increase in cross-sectional area. It is possible to prevent breakage of the pipe. After the cryogenic container is installed at the destination, the cryogenic container can be used by simply disconnecting the reinforcing member and removing the reinforcing member from the neck.

More specifically, according to the structure of claim 2, the container side member is applied to the upper wall back surface of the container body of the inner container, the connecting member is inserted into the neck pipe, and the neck pipe is With the neck side member in contact with at least one of the upper end of the container and the upper end of the neck in the vacuum container, pull the container side member and the neck side member toward each other. By connecting with the connecting member while applying force, the container main body and the upper end of the neck tube can be connected.

Further, according to the structure of claim 3, by tightening the nut so that there is no inclination of the nut pressure contact member, the tensile force acts evenly on the container side member and the neck tube side member. become.

[0014]

【Example】

 A first embodiment of the present invention will be described with reference to FIGS.

The cryostat (cryogenic container) 10 shown in FIG. 2 is provided with a doughnut-shaped liquid helium tank (inner container) 14 for containing a superconducting magnet 12 and liquid helium 13. The liquid helium tank 14 and the donut-shaped radiant heat A shield plate 16 and a doughnut-shaped liquid nitrogen tank 18 are housed in a vacuum container 20 in a vacuum state. Specifically, a hollow portion 11 for sample insertion is formed at the center of the cryostat, the liquid helium tank 14 is inside the radiant heat shield plate 16, the radiant heat shield plate 16 is inside the liquid nitrogen tank 18, and the liquid nitrogen tank 18 is inside. Are housed in vacuum containers 20, and liquid nitrogen 19 is housed in the containers formed on the outer periphery of the liquid nitrogen tank 18.

From the upper portions of the liquid helium tank 14 and the liquid nitrogen tank 18, neck pipes 14a and 18a are respectively extended upward, and above the outer wall portion 80 of the vacuum container 20 corresponding to these neck pipes 14a and 18a. Also, the pipe portions 21 and 22 are extended. The upper ends of the neck tubes 14a and 18a are fixed to the upper ends of the tube portions 21 and 22 by welding while the neck tubes 14a and 18a are inserted into the respective tube portions 21 and 22. The liquid helium tank 14 is supported in the vacuum container 20 in a suspended state with a joint 27 with the upper end of the neck 14a serving as a fulcrum. The radiant heat shield plate 16 and the upper ends of the liquid nitrogen tank 18 are fixed to the middle part of the neck pipe 14a.

The neck pipe 14a discharges the helium gas evaporated in the liquid helium tank 14 to the atmosphere, and the neck pipe 18a discharges the nitrogen gas evaporated in the liquid nitrogen tank 18 to the atmosphere. The tubes 14a and 18a are made of stainless steel or the like having a relatively low thermal conductivity, and their cross-sectional areas are set to be as small as possible, and their vertical lengths are set to be as large as possible.

The fixtures 24 are fixed to the bottom and the upper part of the liquid helium tank 14, and the fixtures 38 are also fixed to the lower side wall and the upper part of the side wall of the radiation shield plate 16 corresponding to the fixtures 24. , 38 are connected to the bottom and the upper portion of the liquid helium tank 14 and the lower and upper portions of the side wall of the radiation shield plate 16 via the connecting rod 41. Similarly, the bottom and top of the radiant heat shield plate 16 are connected to the bottom and top of the side wall of the liquid nitrogen tank 16 via a plurality of connecting rods 43, and the bottom and top of the liquid nitrogen tank 18 are connected to each other. It is connected to the lower part and the upper part of the side wall of the vacuum container 20 via a connecting rod 42. Each of the connecting rods 41, 42, 43 is made of a material having a low thermal conductivity and a certain strength, such as various FRPs.

Next, a reinforcing structure of the neck tube 14a used when carrying the cryostat 10 will be described with reference to FIG.

As shown in the figure, in the joint portion 27, a flange portion 14b protruding outward in the radial direction is formed on the upper end of the neck pipe 14a on the liquid helium tank 14 side, and on the upper end of the pipe portion 21 on the vacuum container 20 side. A flange portion 21b protruding inward in the radial direction is formed, and the flange portion 21b and the flange portion 21b are overlapped with each other and are joined by welding or the like.

The reinforcing member in this structure includes a female screw member (container side member) 50, a connecting rod (connecting member) 52, and a cover plate (neck tube side member) 54. The female screw member 50 is formed in a ring shape having a screw hole 50a formed through the center thereof, and the upper end surface thereof is a top wall (upper wall) of the container body of the liquid helium tank 14 (that is, a portion excluding the neck pipe 14a). 14c It is fixed to the back surface by welding or the like. The connecting rod 52 has a lower male screw portion 52a at its lower end that can be screwed into the screw hole 54a of the female screw member 50, and an upper male screw portion 52b at its upper end. The lid plate 54 has a larger outer diameter than the flange portion 14b, and a threaded hole 54a having a larger inner diameter than the outer diameter of the upper male screw portion 52b is formed at the center thereof.

Next, the procedure for reinforcing the neck tube 14a by these members will be described. First, the connecting rod 52 is inserted into the neck tube 14a from above, and the lower male screw portion 52a of the lower end of the connecting rod 52 is screwed into the screw hole 50a of the female screw member 50 in the liquid helium tank 14. On the other hand, above the neck tube 14a, the lid plate 54 is put on the upper surface of the flange portion 14b while inserting the upper male screw portion 52b of the connecting rod 52 into the screw through hole 54a of the lid plate 54, and further to the upper male screw portion 52b. Tighten the nut 56 with a certain torque. As a result, in the reinforced state as shown in FIG. 1, that is, the female screw member 50 and the cover plate 54 are connected via the connecting rod 52 in the neck tube 14a, and the nut 56 is tightened to tighten the female screw member 50 and the cover plate 54. A tension force in the direction of bringing them closer to each other is applied between and.

In this state, the substantial cross-sectional area of the neck 14a portion is increased by the cross-sectional integration of the connecting rod 52. Therefore, if the entire cryostat 10 is transported in this state, even if a large downward pulling force acts on the neck 14a due to the vertical vibration of the cryostat 10, the pulling force generated on the neck 14a by this pulling force is exerted. It is possible to reduce the stress by the amount of increase in the above-mentioned cross-sectional area, and thereby prevent breakage of the neck tube 14a. Moreover, after the cryostat 10 is installed at the destination, the nut 56 is removed from the upper screw portion 52b, the cover plate 54 is removed from the upper screw portion 52b, and the lower screw portion 52 and the female screw member 50 are screwed together. It is possible to restore the original usable state by the work of only uncoupling and pulling out the connecting rod 52 from the neck pipe 14a.

Next, a second embodiment will be described with reference to FIGS.

In this structure, two sub connecting rods 58 arranged at symmetrical positions and a main connecting rod 60 arranged at an intermediate position between these sub connecting rods 58 are provided, and the cover plate 54 has A screw through hole 54b corresponding to the main connecting rod 60 and two screw through holes 54c corresponding to the sub connecting rods 58 are provided so as to penetrate therethrough. The neck tube 14a is joined to the top wall 14c of the liquid helium tank 14.

A screw portion 58 a that can be inserted into the screw through hole 54 c is formed at the upper end of the sub connecting rod 58, and a contact plate (constituting a container side member) 59 is fixed at the lower end. The contact plate 59 has a plane shape as shown in FIGS. 4A to 4F, that is, a shape in which one end of a circle having a diameter slightly smaller than the inner diameter of the neck tube 14a is cut out. An arcuate groove 59a is formed on the upper surface thereof.

A screw portion 60 a that can be inserted into the screw through hole 54 b is formed at the upper end of the main connecting rod 60, and a contact plate (constituting a container side member) 60 b is fixed at the lower end. The contact plate 60b has a planar shape as shown in FIGS. 4 (e) and (f), that is, a shape having a notch at both ends of a circle having a diameter slightly smaller than the inner diameter of the neck tube 14a. The shape of the notch portion substantially matches the shape of the portion of the contact plate 59 inside the groove 59a (right side in FIG. 4A).

Next, a method of reinforcing the neck tube 14a by this structure will be described. First, as shown in FIG. 4 (a), one sub connecting rod 58 is inserted into the neck pipe 14a from above, and the contact plate 59 is lowered to a position lower than the lower end of the neck pipe 14a. As shown in (b), the sub connecting rod 58 and the contact plate 59 are laterally displaced, and then the sub connecting rod 58 and the contact plate 59 are pulled up so that the upper surface of the contact plate 59 contacts the point wall 14c.

Next, as shown in FIG. 7C, the other sub connecting rod 58 is placed in a state in which the contact plate 59 fixed to the sub connecting rod 58 faces the opposite side to the contact plate 59. The contact plate 59 is inserted into the neck pipe 14a and is lowered to a position below the lower end of the neck pipe 14a. Thereafter, as shown in FIG. 7D, the sub connecting rod 58 and the contact plate 59 are displaced in the opposite direction to the previous displacement direction of the sub connecting rod 58 and the contact plate 59, and from this state, the sub connecting rod 58 is moved. By pulling up the contact plate 59, the groove 59a of the contact plate 59 is brought into contact with the top wall 14c.

Next, as shown in FIG. 5E, the central main connecting rod 60 can be inserted between the abutting plates 60 b fixed to the main connecting rod 60. The contact plate 60b is inserted into the neck tube 14a in the direction, and the contact plate 60b is lowered to a position below both contact plates 59. After that, the main connecting rod 60 and the contact plate 60b are rotated by 90 ° as shown in FIG. 7E, and the main connecting rod 60 and the contact plate 60b are pulled up from this state, so that the contact plate 60b Both ends are pressed against the lower surfaces of both contact plates 59.

In this state, the lid plate 54 is placed on the upper surface of the flange portion 14b while inserting the screw portions 60a and 58a of the main connecting rod 60 and the sub connecting rod 58 into the screw through holes 54b and 54c of the lid plate 54, respectively. Then, the nut 56 is screwed onto each of the screw portions 60a and 58a and tightened with a constant torque. As a result, the contact plate 59 is reinforced as shown in FIG. 3, that is, the contact plate 59 and the cover plate 54 are connected to each other via the sub connecting rod 58 in the neck tube 14a, and both contact plates 59 contact each other. 60b is connected to the cover plate 54 via the main connecting rod 60, and when the nut 56 is tightened, a pulling force is applied between the contact plates 59 and the cover plate 54 so as to bring them closer to each other. The contact plate 60b is in a state of supporting both contact plates 59 from the lower side to the upper side.

Even in this state, damage to the neck pipe 14a during transportation can be prevented by increasing the substantial cross-sectional area of the connecting rods 58 and 60 in the neck pipe 14a. After the cryostat 10 is installed at the destination, all the reinforcing members can be removed from the neck tube 14a in the reverse order of the procedure shown in FIGS. 4 (a) to 4 (f).

Next, a third embodiment will be described with reference to FIGS.

This structure is provided with two connecting rods 62 arranged at symmetrical positions and a supporting rod 64 arranged at an intermediate position between these connecting rods 62, and the cover plate 5 in each of the above-described embodiments is provided. Instead of 4, a specially shaped lid member (container side member) 68 is used.

A threaded portion 62 b is formed on the upper end of the connecting rod 62, and a contact member (constituting a container side member) 63 is fixed to the lower end. The contact member 63 has a shape as shown in FIG. 6, that is, one side surface is formed in an arc shape, and the other side surface is formed as a tapered surface 63a protruding downward as shown in FIG. .

A threaded portion 64b is formed at the upper end of the support rod 64, and a tapered (tapered) conical portion 64a matching the tapered surface 63a is formed at the lower end. Further, a rotation restricting ring 66 is fixed to the back surface of the top wall 14c of the liquid helium tank by welding or the like, and an outer portion of the contact member 63 is provided at a position where the rotation restricting ring 66 faces each other. A rotation regulation groove 66a that can be fitted is provided as a recess.

As shown in FIGS. 7 and 8, the lid member 68 has a disk-shaped base portion 68a, a pillar portion 68b extending upward from two opposite portions of the base portion 68a, and both pillar portions 68a. It integrally has a top wall portion 68c that connects b with each other. The base 68a is provided with a support rod through hole 68d through which the support rod 64 can be inserted, and a screw through hole 68e through which the screw portion 62b of the connecting rod 62 can be inserted, and the top wall 68c. At a position directly above the support rod through hole 68d, a screw through hole 68f through which the screw portion 64b of the support rod 64 can be inserted is provided.

Next, a method of reinforcing the neck tube 14a by this structure will be described. First, with the contact plate 63 down, one connecting rod 62 is inserted into the neck tube 14a, and the contact plate 63 is lowered to a position below the lower surface of the rotation restricting ring 66, and then the connection plate 63 is connected. Rotate the rod 62 appropriately so that the tapered surface 63a of the contact plate 63 faces inward. In this state, the connecting rod 62 and the contact plate 63 are pulled up, and the outer portion of the contact plate 63 is restricted by the rotation restricting ring 66. Fit into the groove 66a from below. Similarly, the other connecting rod 62 is inserted into the neck tube 14a, and the contact plate 63 thereof is fitted into the rotation restricting groove 66a. Due to these fittings, both contact plates 63 become unrotatable around the connecting rod 62.

Next, the support rod 64 is inserted into the neck tube 14a with the conical portion 64a facing down, the conical portion 64a is inserted like a wedge between the tapered surfaces 63a, and the screw portion 64b is attached to the lid member. The nut 56 is reversely screwed to the threaded portion 64b while being inserted into the support rod through hole 68d of 68. Then, the support rod 64 is inserted into the support rod through hole 68d and the screw through hole 68f of the lid member 68, and the screw portions 62b of both the connecting rods 62 are inserted into the screw through holes 68e, while the lid is inserted. The base portion 68a of the member 68 is applied to the upper end surface of the flange portion 14b, the nuts 56 are screwed to both the screw portions 62b, and the nuts 56 previously screwed to the nuts 56 and the screw portion 64b are fixed to a constant torque. Tighten with. As a result, the contact member 63 and the base portion 68a of the lid member 68 are connected via the connecting rod 62 in the neck tube 14a in a reinforced state as shown in FIG. 5, and both contact members 63 rotate. The rotation is stopped by the restricting ring 66, and the nut 56 attached to the threaded portion 62b is tightened to exert a pulling force between the abutting members 63 and the lid member 68 so as to bring them closer to each other. It becomes a state. Moreover, the conical portion 64a of the support rod 64 is pressed between the two tapered surfaces 63a by tightening the nut 56 attached to the screw portion 64b, and the lateral displacement of both abutting members 63 is also caused by the wedge action. It will be in a regulated state.

Even in this state, the increase in the substantial cross-sectional area of the connecting rod 62 in the neck pipe 14a can prevent damage to the neck pipe 14a during transportation. Further, after the cryostat 10 is installed at the destination, all the reinforcing members other than the rotation restricting ring 66 can be removed from the neck pipe 14a by the procedure reverse to the above.

Next, a fourth embodiment will be described with reference to FIGS.

In the third embodiment, the reinforcement is carried out by using the two connecting rods 62. However, the tightening torque by each nut 56 is uniform and proper, specifically, the superconducting magnet 12 It is preferable to adjust the torque so that the stress of the neck tube 14a due to the weight of the liquid helium tank 14 becomes almost zero. Here, if the tightening torque of the nuts 56 on both connecting rods 62 and the pulling force by the connection of both connecting rods 62 are not uniform if reduced, the neck pipe 14a may be deformed during transportation. This torque can be detected by attaching a strain gauge to the neck pipe 14a under atmospheric temperature. However, considering the effects such as the absorption of moisture and air into the neck pipe 14a and the effect, it can be measured before transportation. It is difficult to attach a strain gauge to the neck tube 14a cooled with liquid helium in a short time. Therefore, in this embodiment, it is an object to equalize the tensile force of the connecting rod 62 without detecting the torque by the strain gauge.

Specifically, in this embodiment, a nut pressure contact plate (nut pressure contact plate) is provided between the base portion 68 a of the lid member 68 in the third embodiment and the nuts 56 mounted on the screw portions 62 b of both connecting rods 62. (Member) 70 is interposed. The nut pressure contact plate 70 has a support rod through hole 70b into which the support rod 64 can be inserted and a connecting rod through hole 70c into which both connecting rods 62 can be inserted. A projecting strip (pressure contact portion) 70a extending in the front-rear direction (vertical direction in FIG. 10) is provided in a protruding manner.

With such a nut pressure contact plate 70 interposed between the base portion 68a and the nut 56, the contact portion between the upper surface of the base portion 68a and the pressure contact portion 70a serves as a fulcrum so that the nut pressure contact plate 70 does not tilt. If both nuts 56 are tightened, the pulling force of both connecting rods 62 can always be kept uniform.

Next, a fifth embodiment will be described with reference to FIGS.

The structure shown in this embodiment includes a connecting rod 72, an abutting plate supporting member 74, an abutting plate (container side member) 76, and a lid plate (neck tube side member) 80. The contact plate supporting member 74 constitutes the connecting member in the present invention.

A screw portion 72 a is formed at the upper end of the connecting rod 72, and the contact plate support member 74 is fixed at the lower end. The contact plate support member 74 has a column portion 74a and a contact plate support portion 74b extending downward from the lower surface of the column portion 74a in a bifurcated shape. The outer diameter d of the column portion 74a is set to be slightly smaller than the inner diameter of the neck tube 14a, and a wire passage hole 74b is vertically provided through the column portion 74a. A rotation center shaft 74d and a wire restricting shaft 74c extending in the horizontal direction are provided between the two contact plate support portions 74b, and a rectangular parallelepiped contact plate 76 can rotate about the rotation center shaft 74d. Supported by.

The contact plate 76 has a shape in which the distance L1 from the rotation center shaft 74d to one end surface is longer than the distance L2 from the rotation center shaft 74d to the other end surface. Therefore, when it receives no supporting force from the outside, it is rotated counterclockwise in FIG. 11 by its own weight. A wire passing hole 76a is formed in a portion of the contact plate 76 on the side having the distance L2 in the up-down direction, and a wire 78 is inserted into the wire passing hole 76a. The lower end of the wire 78 is fixed to the lower surface of the contact plate 76.

The lid plate 80 is formed in a disc shape having an outer diameter larger than the inner diameter of the neck tube 14a, and has a screw through hole 80a at the center through which the screw portion 72a can be inserted. The wire through hole 80b is provided at a position deviated from.

Next, a procedure for reinforcing the neck tube 14a with this structure will be described.

First, the wire 78 led out from the wire through hole 76a of the contact plate 76 is passed through the back side (right side in FIG. 11) of the wire regulating shaft 74c, and is inserted from the bottom to the top through the wire through hole 74b. The wire portion is inserted through the wire through hole 80b of the cover plate 80 from the bottom to the top, and the screw portion 72a of the connecting shaft 72 is inserted through the screw hole 80a at the center of the cover plate 80. Then, by pulling the wire 78 upward, the contact plate 76 is forcibly erected as shown by the chain double-dashed line in FIG. 11, and the contact plate 76 and the contact plate supporting member 74 are set downward. The connecting shaft 72 is inserted into the neck tube 14a. Then, after lowering the contact plate 76 sufficiently below the ceiling wall 14c of the liquid helium tank 14, the tension of the wire 78 is loosened to bring the contact plate 76 into a substantially horizontal state by its own weight. In this state, the connecting shaft 62 is pulled up. As a result, the contact plate 76 contacts the back surface of the top wall 14c of the liquid helium tank at the peripheral edge of the neck tube 14a, and this contact fixes the contact plate 76 in the horizontal state as shown by the solid line in FIG. be able to. Furthermore, the cover plate 80 is brought into contact with the flange portion 14b at the upper end of the neck 14a, the nut 56 is attached to the screw portion 72a, and the nut 56 is tightened to obtain a reinforcing state as shown in FIG.

In this state, the contact plate 76 is connected to the cover plate 80 via the contact plate support member 74 and the connecting shaft 72, and the nut 56 is tightened to tighten the contact plate 76 and the cover plate. Since a tensile force is applied between 80 and 80, the tensile stress generated in the neck 14a when the downward tensile force acts on the neck 14a during transportation can be reduced, The break can be prevented in advance.

Although the above-described embodiments have all described the reinforcement of the neck pipe 14a extending from the liquid helium tank 14a, the neck pipe 18a shown in FIG. The present invention can also be applied. In this case, the liquid nitrogen tank 18 corresponds to the inner container in the present invention.

In each of the above-described embodiments, the flange portion 14b on the neck tube 14a side is joined to the flange portion 21b on the vacuum container 20 side, and the two are joined together. Even in a structure in which the side portion covers the upper end of the neck tube, the same effect as above can be obtained by bringing the neck side member into contact with this empty container side portion. . Further, when both the portion on the vacuum container side and the upper end portion of the neck tube are exposed upward, the neck side member may be applied to both of them.

[0055]

[Effect of device]

 As described above, according to the present invention, a reinforcing member is inserted into the neck pipe extending from the inner container, and the neck member is reinforced by connecting the container body portion of the inner container to the upper end of the neck pipe by the reinforcing member. Therefore, even if a downward pulling force is applied to the neck pipe during transportation of the cryogenic container, the tensile stress generated in the neck pipe due to this pulling force should be sufficiently reduced. Therefore, it is possible to avoid inconveniences such as breakage of the neck tube without breaking the vacuum in the vacuum container.

More specifically, according to the structure of claim 2, the container side member is brought into contact with the upper wall back surface of the container main body portion of the inner container, and the upper end of the neck pipe and the neck pipe in the vacuum container. The neck side member is brought into contact with at least one of the upper end and the portion to be joined, and the connecting member is inserted into the neck pipe so that the container side member and the neck side member are pulled toward each other. The above-mentioned reinforcement can be performed by a simple work of simply connecting while applying tension, and the connection member and the like can be easily removed from the neck canal by the reverse operation.

Further, according to the structure of claim 3, between the nuts mounted on the upper ends of the plurality of connecting members and the neck pipe side member, only the central portion of the upper face of the neck pipe side member is contacted. Since the nut pressure contact member is interposed, by tightening the nut so that the nut pressure contact member does not tilt, the tensile force of each connecting member can be maintained evenly. This has the effect of preventing the neck canal from being deformed due to.

[Brief description of drawings]

FIG. 1 is a sectional front view showing a neck canal reinforcing structure according to a first embodiment of the present invention.

FIG. 2 is an overall configuration diagram of a cryostat to which the neck reinforcement structure is applied.

FIG. 3 is a sectional front view showing a neck canal reinforcing structure according to a second embodiment.

4 (a) to 4 (f) are cross-sectional plan views showing a method for reinforcing a neck tube with the above structure.

FIG. 5 is a sectional front view showing a neck reinforcement structure in a third embodiment.

6 is a cross-sectional view taken along the line AA of FIG.

FIG. 7A is a plan view of a lid member used in the neck reinforced structure, and FIG. 7B is a side view.

8 is a sectional view taken along line BB of FIG. 7 (b).

FIG. 9 is a sectional front view showing a main part of a neck canal reinforcing structure according to a fourth embodiment.

10 is a cross-sectional view taken along the line CC of FIG.

FIG. 11 is a sectional front view showing a neck canal reinforcing structure in a fifth embodiment.

FIG. 12 is a side view of an abutting plate and an abutting plate supporting member used in the neck pipe reinforcing structure.

[Explanation of symbols]

 10 Cryostat 14 Liquid Helium Tank (Inner Container) 14a Neck 14c Top Wall of Liquid Helium Tank 20 Vacuum Container 50 Female Thread Member (Container Side Member) 52 Connecting Rod (Connecting Member) 54 Lid Plate (Neck Side Member) 56 Nut 58 Sub connecting rod (connecting member) 59 Abutting plate (container side member) 60 Main connecting rod (connecting member) 62 Connecting rod (connecting member) 63 Abutting member (container side member) 68 Lid member (neck tube side member) 70 Nut pressure contact member 70a Pressure contact part 72 Connection rod (connection member) 74 Contact plate support member (connection member) 76 Contact plate (container side member) 80 Lid plate (neck tube side member)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tsutomu TAI 1-5-5 Takatsukadai, Nishi-ku, Kobe-shi Kobe Steel Works, Kobe Research Institute (72) Inventor Toru Hashimura 1 Takatsukadai, Nishi-ku, Kobe 5th-5th, Kobe Steel Research Institute, Kobe Steel, Ltd. (72) Inventor Akira Sakurai 1-5th, Takatsukadai, Nishi-ku, Kobe City, 5th, Kobe Steel Research Institute, Kobe Steel, Ltd. (72) Inventor Shigenori Ebihara 8-11, Kasugadai, Nishi-ku, Kobe 11 (72) Inventor ▲ Hama ▼ Tabei 1-6-4, Takenodai, Nishi-ku, Kobe

Claims (3)

[Scope of utility model registration request] 1. An inner container having a neck tube extending upward from a container body and containing a cryogenic substance therein, and an upper end of the neck tube are joined to each other while supporting the inner container in a suspended state. In a cryogenic container having a vacuum container for accommodating a cryogenic container, the cryogenic container is provided with a reinforcing member for connecting a container body portion of the inner container and an upper end of the neck pipe in a state of being inserted into the neck pipe. Neck reinforced structure. 2. The neck pipe reinforcing structure for a cryogenic container according to claim 1, wherein the reinforcing member includes a container side member that abuts an upper wall back surface of a container body of the inner container, an upper end of the neck pipe, and a vacuum. A neck side member that abuts at least one of the portion joined to the upper end of the neck in the container, and a pulling direction that is inserted into the neck and that brings the container side member and the neck side member closer to each other. A neck tube reinforcing structure for a cryogenic container, comprising: a connecting member that connects the two while applying a force. 3. The neck pipe reinforcing structure for a cryogenic container according to claim 2, further comprising a plurality of connecting members, wherein each connecting member has a lower end connected to the container-side member and a screw portion formed at an upper end. A nut press-contacting member that is composed of a main body having a threaded portion penetrating the neck side member and a nut attached to the threaded portion, and that is interposed between the lower surface of the nut and the upper surface of the neck side member. A pressure contact portion is provided at an intermediate position between both connecting members on the lower surface of the nut pressure contact member, and the nut pressure contact member can be tilted with the pressure contact position between the pressure contact portion and the neck side member as a fulcrum. A neck tube reinforcing structure for a cryogenic container characterized by comprising members.