JP2014059022A - Heat insulation support spacer in vacuum heat insulation low temperature equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat insulation support spacer in a vacuum heat insulation low temperature container in which an adiathermancy of the heat insulation support spacer of a transfer tube acting as a vacuum heat insulation low temperature container is excellent and a heat loss can be reduced.SOLUTION: An inner peripheral part and an outer peripheral part of plastic spongy body 39 are provided with plastic protection rings 40, 41 made of stainless steel, epoxy resin or the like having a low coefficient of thermal conductivity, for example, within an inner vacuum space of a vacuum pipe 4v having blades 4v, 4b, contact curve surfaces of the protection ring 40 and the spongy body 39 and contact curve surfaces of the protection ring 41 and the spongy body 39 are integrally assembled with adhesive agent or the like and then outgoing pipe 4f of a metallic bellow pipe for transferring refrigerant and the blade 4b are held inside the protection ring 40.

Description

The present invention relates to a heat insulating support spacer in a vacuum heat insulating low-temperature device, and is suitable for use in, for example, holding a low-temperature fluid channel pipe, which is an object to be held in a transfer tube, from a high-temperature holding member in an adiabatic manner.

Superconductivity such as MEG (magnetoencephalograph), NMR (superconducting nuclear magnetic resonance apparatus), MRI (magnetic resonance imaging) apparatus, superconducting magnet and superconducting cable that generate superconductivity at liquefied gas temperature such as liquid nitrogen, liquid neon and liquid helium In the apparatus, it is necessary to hold each cooled object at a cooling temperature, and a liquefied gas storage container that is a cooling refrigerant, or a cooling device that circulates and transfers the cold of a refrigerator, for example, helium gas that is a cooling refrigerant. There is a need for a transfer tube of a heat transfer pipe for cooling refrigerant transfer, which is a kind of vacuum heat insulation low-temperature equipment that connects the superconducting device and the superconducting device.

A transfer tube, which is one of the low-temperature insulated containers, is mainly used for conducting conduction in a vacuum space so that both the outer tube at room temperature and one or more inner tubes at which low-temperature fluid flows are not in contact with each other. It is composed of a spacer that prevents heat and adiabatically and physically holds and a laminated heat insulating material that is wound around the outer periphery of the inner tube to prevent intrusion of radiant heat, and maintains heat insulating performance.

A structure of a spacer of a heat insulating holding material used in a conventional transfer tube and holding an inner pipe of a low temperature fluid flow path in the transfer tube from a higher temperature support member is disclosed in Japanese Patent Application Laid-Open No. 2008-8482 (Patent Document 1). Has been.

By improving the heat insulation performance of the transfer tube, the cooled object can be cooled to a lower temperature, thereby improving the superconductor function, improving the superconducting device measurement function, and improving the image quality of scanning electron microscope equipment. it can. Further, by increasing the heat insulation performance of the transfer tube, it is possible to reduce the evaporation amount of the liquefied gas to be transferred and improve the transfer efficiency of the liquefied gas.

Japanese Patent No. 04512644

However, in patent document 1, the holding body which comprises a spacer is comprised with the solid member, and since the heat loss which penetrate | invades by the conduction heat transfer from the high temperature side to the inner pipe side of the low temperature side becomes large, heat insulation performance falls. However, the cooling amount of the low-temperature fluid flowing through the inner pipe is reduced, the cooling temperature of the cooled object is increased, and the superconducting function of the superconductor in the superconducting device is lowered.

This invention is made | formed in view of the said condition, and it aims at providing the heat insulation support spacer arrange | positioned in the vacuum heat insulation low temperature apparatus which is excellent in heat insulation and can reduce a heat loss.

In order to achieve the above object, the structure of the heat insulating support spacer used in the vacuum heat insulating low temperature apparatus of the present invention is characterized in that a part of the heat insulating material is formed of a spongy spongy body.

That is, the structure of the heat insulating support spacer according to claim 1 is characterized in that the heat insulating material is formed of a plastic cylindrical spongy body.

According to this spacer structure, the amount of conduction heat transfer from the high temperature portion of the outer peripheral portion of the spongy body to the low temperature portion of the inner peripheral portion is the inside of the shell constituent member in the foam-like shell structure constituting the spongy body. The total amount of conduction heat transfer, and because of the shell structure, the actual thickness perpendicular to the conduction heat transfer direction is about several tenths smaller than that of a solid cylinder, and the heat transfer in the conduction heat transfer direction is further reduced. The distance is also the length along the shell constituent member, which is several times longer than that of a solid cylindrical body.

The conduction heat transfer amount Qc (W) of the spacer is expressed by the following equation.

Qc = λSΔT / L (1)

Here, λ is the thermal conductivity (W / (m · K)) of the heat transfer member, S is the cross-sectional area (m ² ) of the heat transfer member in the direction perpendicular to the conduction heat transfer direction, and L is the conduction of the heat transfer member The length (m) in the heat transfer direction and ΔT are the temperature difference (K) at both ends of the heat transfer member.

Therefore, in order to reduce the amount of heat transfer Qc and improve the thermal insulation performance of the spacer, if ΔT cannot be reduced, it is necessary to reduce S or increase L. According to this spacer structure, S is Since the size can be reduced and the length L can be increased, it is possible to provide a spacer having a reduced conduction heat transfer amount Qc.

Moreover, in order to achieve the above object, the structure of the heat insulating support spacer according to claim 2 is made of, for example, stainless steel or plastic having a low thermal conductivity at the outer peripheral portion and the inner peripheral portion of the cylindrical sponge-like body. A ring is provided, and the contact portion between both rings and the spongy body is integrated with an adhesive or the like.

According to the structure of this spacer, when the load acting on the spacer such as the weight of the inner pipe increases, the load does not act intensively on the contact surface of the inner pipe directly on the spongy body having low strength, and the inner circumference Since it is received once by the ring and the load is received by the entire surface of the spongy body on the outer periphery of the ring joined to the inner ring, the spongy body can be prevented from being destroyed and the position of the inner tube can be maintained, and the length of L can be maintained. In addition, it is possible to provide a spacer with a reduced conduction heat transfer amount Qc. The effect of the ring provided on the outer periphery is also the same.

In order to achieve the above object, the structure of the heat insulating support spacer according to claim 3 is characterized in that a metal ring made of, for example, pure aluminum having a low emissivity is provided between the outer peripheral portion and the inner peripheral portion of the spongy body. 1 or a plurality of metal or non-metal cylinders, for example, with a film of polyester or polyimide deposited with aluminum or gold, and a contact portion between the ring or cylinder and the spongy body. It is characterized by being integrated with an adhesive or the like.

According to the structure of this spacer, in order to reduce the amount of heat intruding into the hollow space inside the cancellous body by radiant heat, a radiant heat intrusion path space prevents the intrusion of radiant heat by placing a cylinder with a low emissivity. it can. Thereby, the spacer which made heat loss small can be provided.

Moreover, the structure of the heat insulation support spacer of Claim 4 for achieving the said objective is characterized by making the spacer shape into the sponge-like polygonal cylinder.

According to the structure of this spacer, the contact point area with the outer tube is smaller than in the case of a spongy body, and the conduction distance from the contact point to the inner tube is also longer, so a spacer with reduced heat loss can be provided. It becomes.

In order to achieve the above object, the structure of the heat insulating support spacer according to claim 5 is characterized in that the contact surfaces of the spongy body, the outer periphery, and the inner peripheral ring are combined without being integrated.

According to the structure of this spacer, the load such as the weight of the inner tube can be held with a small contact surface, so that the contact area of the place where the heat moves is further reduced, and the inner tube from the contact point with the outer tube. Since the conduction heat transfer distance becomes longer, a spacer with reduced heat loss can be provided.

Further, in order to achieve the above object, the structure of the heat insulating support spacer according to claim 6 is formed by depositing aluminum or gold on the side surface of the spongy body, for example, a polyimide film, and depositing aluminum or gold on the radiant heat intrusion side. It is characterized by having a structure arranged so that the opposite surfaces face each other.

According to the structure of this spacer, since the amount of radiant heat entering the side surface of the sponge cylinder can be reduced, a spacer with reduced heat loss can be provided.

Moreover, the structure of the heat insulation support spacer of Claim 7 for achieving the said objective WHEREIN: The spacer shape was made into the structure which can be halved and attached to a radial direction.

According to the structure of this spacer, since it is possible to install the spacer without damaging the laminated heat insulating material even after the laminated heat insulating material is wound outside the spacer installation, the radiation rate of the laminated heat insulating material is kept small. It is possible to provide a spacer that can be held and has a small heat loss that prevents heat penetration due to radiant heat.

In order to achieve the above object, the structure of the heat insulating support spacer according to claim 8 is characterized in that a plurality of inner pipes can be insulated and held.

According to the structure of this spacer, it is possible to construct an inner pipe of two flow paths that constitute a reciprocating path in one outer pipe, and therefore it is possible to provide a spacer that reduces the total heat loss of both reciprocating flow paths. Become.

Moreover, the structure of the heat insulation support spacer of Claim 9 for achieving the said objective was limited to the case where a vacuum heat insulation low temperature apparatus is a transfer tube, and comprised the to-be-supported body with the cooling refrigerant transfer piping. It is characterized by that.

According to the structure of this spacer installed in the transfer tube, when the vibration of the fluid flowing in the cooling refrigerant transfer pipe or the mechanical vibration of the refrigerator for cooling the refrigerant occurs, the sponge-like body has the vibration. The laminated insulation that is absorbed by the elastic function and wound around the cooling refrigerant transfer pipe can be prevented from being damaged by friction with the spacer, so that the radiation rate of the laminated insulation can be kept small, and heat penetration due to radiant heat is prevented. It is possible to provide a spacer with a small heat loss that is prevented.

Moreover, the structure of the heat insulation support spacer of Claim 10 for achieving the said objective was comprised with the laminated adhesive body of the activated carbon particle, It is characterized by the above-mentioned.

According to the structure of this spacer, the residual gas in the vacuum space where the spacer is arranged at the low temperature part of the laminated adhesive can be adsorbed by activated carbon, so that the vacuum pressure is further reduced, the vacuum heat insulation performance is improved, and the heat loss is further reduced. Can be provided.

ADVANTAGE OF THE INVENTION According to this invention, the heat insulation support spacer suitable for arrange | positioning in the transfer tube of the vacuum heat insulation low temperature apparatus which made heat loss small and excellent in heat insulation performance can be provided.

It is a block diagram which shows the low-temperature cooling device using the transfer tube for low temperature fluids which is the vacuum heat insulation low temperature apparatus of 1st Example of this invention. It is sectional drawing of the transfer tube of the heat insulation support spacer arrangement | positioning part in a transfer tube. FIG. 3 is a cross-sectional view in the longitudinal direction of a transfer tube of a heat insulating support spacer arrangement portion as viewed in the direction of arrows XX in FIG. 2. It is sectional drawing of the transfer tube of the spacer arrangement | positioning part of 2nd Example of this invention. It is longitudinal direction sectional drawing of the transfer tube of the spacer arrangement | positioning part of 3rd Example of this invention. It is sectional drawing of the transfer tube of the spacer arrangement | positioning part of 4th Example of this invention. It is sectional drawing of the transfer tube of the spacer arrangement | positioning part of 5th Example of this invention. It is sectional drawing of the transfer tube of the spacer arrangement | positioning part of 6th Example of this invention. It is longitudinal direction sectional drawing of the transfer tube of the spacer arrangement | positioning part of 7th Example of this invention. It is sectional drawing of the transfer tube of the spacer arrangement | positioning part of YY arrow in FIG. 9 of 7th Example of this invention. It is sectional drawing of the transfer tube of the spacer arrangement | positioning part of 8th Example of this invention.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. The same reference numerals in the drawings of the respective embodiments indicate the same or equivalent.

[Example 1]

The low-temperature cooling device using the transfer tube for low-temperature fluid, which is the vacuum heat insulating low-temperature equipment of the first embodiment of the present invention, will be described more specifically with reference to FIG. 1, FIG. 2, and FIG. FIG. 1 is a block diagram showing a low-temperature cooling apparatus using a transfer tube according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view of a transfer tube in a heat insulating support spacer arrangement portion in a vacuum heat insulating low temperature apparatus, and FIG. It is longitudinal direction sectional drawing of the transfer tube of the heat insulation support spacer arrangement | positioning part of XX arrow. Moreover, the arrow in a figure shows the flow direction of a refrigerant | coolant.

The transfer tube and the cooling device, which are vacuum adiabatic low-temperature devices of the present embodiment, are used as a cooling device for the superconducting bulk magnet 1 which is a kind of superconducting magnet. The transfer tube for the reciprocating path is intended to improve the performance of the apparatus while solving the problems of the prior art, and becomes a magnetic field generating means in the thin heat insulating vacuum container 2 which is the first vacuum heat insulating container. A metal bellows is contained in vacuum pipes 4v and 5v, each of which is composed of a vacuum bellows pipe having a small diameter and a small bend radius in order to transfer a refrigerant that cools the superconducting bulk material 3 to a low temperature. It has flexible transfer tubes 6g and 6h each incorporating a reciprocating pipe 4f and 5f of a low-temperature refrigerant, which is a holding body composed of tubes, and a superconducting magnet is inserted into and removed from a slender space. It has a moving operability.

Further, in the transfer tube and the cooling device of the present embodiment, the temperature of the refrigerant to be transferred is lowered to 40K or lower, and the cooling temperature of the high temperature superconducting bulk body 3 of, for example, yttrium-barium-copper-oxygen system is 77K or lower. In other words, the magnetic flux density capturing performance is improved by the magnetic field of the magnetizing external magnet 7 at a temperature lower than the superconducting temperature of the object to be cooled.

The superconducting bulk body 3 and its cooling stage 8 can be installed in a thin vacuum vessel 2, and the superconducting bulk magnet 1 can be installed in an elongated cavity by making the transfer tube for transferring the refrigerant flexible enough to bend. . The inside of the vacuum vessel 2 is evacuated using an external vacuum pump 100 through a vacuum exhaust valve 30.

In a superconducting bulk magnet 1 having a high-temperature superconducting bulk body 3, the superconducting bulk body 3 is disposed in a thin vacuum vessel 2 that is vacuum-isolated from the atmosphere for heat insulation, and is attached to the tip of a sleeve 9 made of stainless steel having a low thermal conductivity. For example, an aluminum alloy protective ring 10 is thermally and mechanically integrated on an airtight and metallurgically integrated copper cooling stage 8 having a large thermal conductivity.

The cooling device 99 having the second vacuum vessel 11 includes a helium low-temperature refrigerator 14 having a refrigerator cooling stage 13 having a screw-type heat exchanger 12. The cooling device 99 further includes a compressor 15 and a countercurrent heat exchanger 16 which are refrigerant circulation means. In the counterflow heat exchanger 16, heat is exchanged between refrigerant flowing in the transfer reciprocating straight pipes 4s and 5s, for example, helium gas circulating refrigerant.

The high-pressure circulating refrigerant of helium gas having a pressure of about 1 MPa, which is pressurized by the compressor 15, flows into the cooling device 99 at a room temperature of 300 K, and the return path of the countercurrent heat exchanger 16 in the forward path of the countercurrent heat exchanger 16. Heat is exchanged with the low-temperature circulating refrigerant in the inside to reach a temperature of about 50K, and then heat exchange is performed with the screw-type heat exchanger 12 cooled by the cooling stage 13 which is a cold generation part of the refrigerator, resulting in a temperature of about 35K. . The low-temperature and high-pressure circulating refrigerant that has flowed from the forward straight pipe 4 s into the forward pipe 4 f of the metal bellows pipe flows into the superconducting bulk magnet 1 from the outlet of the transfer tube 6 g and constitutes a bionet joint having a sleeve 9. 17 flows into the bottom surface of the cooling stage 8 at the tip of the sleeve 9 from the tip outlet 18, cools the cooling stage 8 to a temperature of about 40K, and cools the superconducting bulk body to about 40K.

Here, the cold transport performance by the circulating refrigerant is advantageous because a large amount of cold can be transported with a small amount of circulating refrigerant by increasing the specific heat of the circulating refrigerant. If the circulating refrigerant is helium gas, the pressure is reduced. It is effective to increase the specific heat of the refrigerant.

The heated high-pressure circulating refrigerant after cooling is in the form of a plastic cylinder attached to the outer peripheral portion of the tip portion 20a of the bottomed cylindrical partition wall 20 that secures the vacuum space 19a on the outer peripheral portion of the circulating refrigerant supply straight pipe 17. While the sleeve 9 is cooled while flowing through the gap 22 between the support 21 and the inner wall of the sleeve 9, heat intrusion enters the low temperature portion from the normal temperature flange 23 portion of the sleeve 9 by heat conduction, or from the inner wall of the normal temperature vacuum vessel 2. The sleeve 9 heated by radiant heat entering the sleeve 9 flows while cooling, flows into the circulating refrigerant recovery pipe 25 through the vent hole 24, and the metal bellows pipe of the transfer tube 6h at the outlet of the bayonet joint. It flows into the return pipe 5f and is recovered by the cooling device 99.

The outer periphery of the circulating refrigerant recovery pipe 25 is composed of a vacuum layer 19b with a partition wall 26, and by extending the length of the partition wall 26 in the longitudinal direction, it penetrates from the ordinary temperature flange 27 of the bayonet into the low-temperature circulating refrigerant recovery pipe by heat conduction. Reduces intrusion heat.

Next, the circulating refrigerant flows into the return path of the countercurrent heat exchanger 16 in the cooling device 99, cools the circulating refrigerant in the forward path in the countercurrent heat exchanger 16, and exits the countercurrent heat exchanger 16. The refrigerant reaches normal temperature and flows into the compressor 15 through the flow rate adjusting valve 29, and is pressurized again to become high-pressure circulating refrigerant at normal temperature and circulates in the cooling device 99.

As shown in the cross-sectional view of the transfer tube 6g in FIG. 2 (the transfer tube 6h has the same structure) and the longitudinal cross-sectional view of the transfer tube 6g in FIG. 3, which is a cross-sectional view taken along the line XX in FIG. The pipe 4f (same for the return pipe 5f) is composed of, for example, a stainless steel metal bellows, and each outer peripheral portion is covered with a metal blade 4b knitted with a thin stainless steel wire in a cylindrical shape (the same applies to the blade 5b). The end of the blade 4b is metallurgically fixed at the end of the forward pipe 4f (not shown in FIGS. 2 and 3), and the pressure of the high-pressure circulating refrigerant flowing in the forward pipe 4f is The low-temperature metal bellows pipe constituting the forward pipe 4f extends in the vacuum space 19 in the vacuum pipe 4v (or the vacuum pipe 5v in the transfer tube 6h), and comes into strong contact with the inner wall of the room-temperature vacuum pipe 4v. Circulate The temperature of the coolant rises, that the object to be cooled can not be cooled to a predetermined temperature, the blade 4b is prevented.

The space between each of the forward pipe 4f and the backward pipe 5f and the blades 4b and 5b (not shown in FIG. 1) in FIG. If time is taken, it will be evacuated and the function of vacuum insulation will be produced.

The outer peripheral portions of the blades 4b and 5b are wound with multiple layers of laminated heat insulating materials 4c and 5c (not shown in FIG. 1) to prevent radiant heat.

Blades 4vb and 5vb (not shown in FIG. 1) braided with a thin stainless steel wire are also provided on the outer periphery of the vacuum pipes 4v and 5v, and both ends thereof are metallurgical with both ends of the respective vacuum pipes 4v and 5v. The blades 4vb and 5vb prevent the bellows from contracting when the inside of the vacuum pipes 4v and 5v is evacuated.

The low temperature part of the refrigerator 14 is hermetically fixed to the vacuum vessel 11, the working fluid of helium gas circulating in the refrigerator is supplied from the compressor 32, and the high pressure helium gas is supplied to the refrigerator 14 through the high pressure pipe 33. Then, adiabatic expansion occurs in the refrigerator to generate cold, and the expanded low-pressure helium gas is collected by the compressor through the pipe 34 and compressed again.

The flange 35 of the vacuum vessel 2 is fastened with bolts (not shown) or the like through O-rings (not shown) together with the flanges 23 and 27, so that the inside and the atmosphere are hermetically isolated. The flange 27 has a bolt pitch configuration that can be attached and detached separately from the other two flanges. The flange 27 hermetically isolates the high-pressure circulating refrigerant from the atmosphere.

The transfer tubes 6g and 6h are airtightly connected to the vacuum vessel 11 and the atmosphere, and share the vacuum space 19.

The magnetization procedure of the high temperature superconducting bulk body 3 will be described. The magnetizing external magnet 7 is a solenoid superconducting magnet, for example, which excites a magnetic field of several Tesla in the atmospheric space 37 and inserts a room temperature superconducting bulk body at the position shown in FIG. Thereafter, the vacuum space 19 of the transfer tube 6g, 6h for the reciprocating path of the circulating refrigerant communicating with the inside of the cooling device 99 and the cooling device is sufficiently evacuated through the vacuum pipe 101 by the external vacuum pump 100 to ensure the heat insulating function. To do.

Thereafter, the circulating refrigerant of high-pressure helium gas is cooled by the cooling device 99 by the screw heat exchanger 12 and the countercurrent heat exchanger 16 cooled by the refrigerator 14, and is transferred by the transfer tube 6g. The cooling stage 8 is cooled to a temperature of about 40 K, and the high-temperature superconducting bulk body 3 thermally integrated with the cooling stage 8 is cooled to a temperature of about 40 K below the superconducting critical temperature, and the circulating refrigerant after cooling passes through the transfer tube 6 h. It is collected in the cooling device 99.

Thereafter, when the magnetic field of the magnetizing external magnet 7 is demagnetized, an induced current is generated in the bulk body in accordance with the magnetic field change in the high-temperature superconducting bulk body 3, and the current is in the bulk body having zero electric resistance as long as it is cooled. It continues to flow and captures the magnetic field almost the same as several Tesla of the magnetized external magnet 7 which is almost excited, and the strong superconducting bulk magnet 1 is obtained. Thereafter, the magnetizing external magnet 7 is removed.

2 and 3, the cylindrical spacer of the transfer tube 6g is composed of, for example, a plastic spongy body 38 made of polyimide, and there is no bubble portion having residual gas in the foam. Breathability is ensured in the foam. When the forward pipe 4f and the blade 4b, which are the cooling refrigerant support, are passed through the internal cavity of the sponge-like body 38 and the gravity direction is the lower side of the page, the weight is the point of contact A with the inner peripheral surface. I support it. The outer peripheral part of the spongy body 38 and the contact part B of the inner peripheral surface of the vacuum pipe 4v support the weight of the cooling refrigerant forward pipe 4f, the blade 4b and the spongy body 38. The weight applied to the spongy body 38 is determined by the arrangement pitch of the spongy body 38.

The heat entrance path by conduction heat transfer from the normal temperature vacuum pipe 4v to the low temperature forward pipe 4f and its blade 4b through the sponge 38 is mainly a linear distance path from the contact point A to the contact point B. .

Therefore, according to the heat insulating support spacer used in the transfer tube in the present embodiment, the amount of conduction heat transfer from the high temperature portion of the outer peripheral portion of the spongy member 38 to the low temperature portion of the inner peripheral portion constitutes the spongy member 38. This is the total amount of heat conduction inside the shell component in the foam-like shell structure, and the real thickness perpendicular to the conduction heat transfer direction of the polyimide shell constituting the foam is very thin, solid cylinder Compared to the case of a solid cylindrical body, the heat transfer distance in the direction of conduction heat transfer is a continuous conduction length in the shape of a dogleg along the shell component. It is several times longer. As a result, it is possible to provide a spacer whose conduction heat transfer amount Qc is reduced to several tenths that of the prior art. Therefore, by having this spacer structure, there is an effect that a transfer tube which is a vacuum heat insulating low temperature apparatus with a small heat loss can be provided.

[Example 2]

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 4 shows a cross-sectional view of the transfer tube 6g of the spacer arrangement portion of the present invention.

In the spacer of the second embodiment, the plastic sponge-like body 39 has an inner peripheral portion and an outer peripheral portion that are larger in density than the sponge-like body 39 and have a low thermal conductivity, such as stainless steel or epoxy resin. The first embodiment is that a protective ring 40, 41 made of plastic or the like is provided, and the contact curved surface of the protective ring 40 and the spongy body 39 and the contact curved surface of the protective ring 40 and the spongy body 39 are integrated with an adhesive or the like. The other points are basically the same as the first embodiment.

In this second embodiment, the weight of the cooling refrigerant forward pipe 4f and its blade 4b, the spongy body 39 and the protective rings 40 and 41, the cooling refrigerant forward pipe 4f and the blade 4b are measured at the inner periphery of the protective ring 40. I support it. Furthermore, the deformation of the forward pipe 4f caused by the thermal contraction due to the cooling of the forward pipe 4f and the blade 4b and the extension of the forward pipe 4f due to the pressure of the cooling refrigerant transferred in the forward pipe 4f is caused by the spacer. There is a case where a load acting when restraining is added.

The load supported by the spacer is first received by the protective ring 40, and the load is received by the entire spongy body 39 integrated with the entire circumference of the protective ring 40, and then received by the protective ring 41 integrated with the spongy body 39, Finally, it is supported by the vacuum pipe 4v.

According to the structure of this spacer, the load supported by the inner peripheral portion of the protective ring 40 can be supported by the entire spongy body 39, so that the deformation of the spongy body 39 due to the load can be further reduced. It can prevent that 4b moves to the high temperature side vacuum piping 4v side, and contacts.

Therefore, according to the heat insulating support spacer used in the transfer tube in this embodiment, it is possible to provide a spacer that can reduce the deformation of the spongy body 39 even when the load acting on the inner peripheral portion of the protective ring 40 increases. It becomes. Therefore, the present spacer structure has an effect of providing a transfer tube with a small heat loss.

[Example 3]

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 5 shows a longitudinal sectional view of the lance tube 6g of the spacer arrangement portion of the present invention.

In the spacer of the third embodiment, a female screw 43 is provided on the inner peripheral portion of a plastic protective ring 42 made of, for example, stainless steel or epoxy resin, which has a low thermal conductivity in the inner peripheral portion of the plastic spongy body 39. For example, a connecting ring 45 made of stainless steel provided with a male screw 44 fitted thereto is provided, and the contact curved surface of the protective ring 42 and the spongy body 39 are integrated with an adhesive or the like. Both ends of the connecting ring 45 are airtight and metallurgically integrated with a connection ring 46 that is airtight and metallurgically integrated at the end of the cooling refrigerant forward passage 4f. Further, the end of the cooling refrigerant blade 4b is also airtight and metallurgically integrated with the connecting ring 45. These points are different from the second embodiment, and the other points are basically the same as those of the second embodiment.

In this third embodiment, the inner peripheral portion of the protective ring 42 and the connection ring 45 are fixed and supported in a heat insulating manner in the contact portion between the female screw 43 and the male screw 44 in the vacuum space 19. The contact location is a linear contact on the screw surface, the contact area is narrow, the amount of heat transfer on the contact surface is further reduced, and a spacer with reduced heat loss can be provided. Therefore, the present spacer structure has an effect of providing a transfer tube with a small heat loss. Further, the relative positions of the spacer and the forward tube 4f can be stably secured by screw fixing, and it is possible to prevent the forward tube 4f and the blade 4b from moving and contacting the high temperature side vacuum pipe 4v.

[Example 4]

Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 6 shows a cross-sectional view of the transfer tube 6g of the spacer arrangement portion of the present invention.

In the spacer of the fourth embodiment, a bright surface cylindrical body made of, for example, aluminum having a low emissivity or a low emissivity of, for example, aluminum or gold is vapor-deposited in the circumferential direction inside the plastic spongy body 39, for example, polyester. This is different from the second embodiment in that a bright surface cylindrical body 47 made of plastic such as stainless steel or epoxy resin with a film or a polyimide film bonded to the front and back surfaces is inserted and arranged. This is basically the same as the embodiment. The bright surface cylindrical body 47 and the spongy body 39 are integrated with an adhesive or the like at least at the end of the insertion side surface.

In the fourth embodiment, the amount of heat penetration can be reduced because the radiant heat entering the hollow space in the spongy body 39 can be reflected by the inserted bright cylindrical body 47 and prevented from entering the lower temperature side. Thus, a spacer with reduced heat loss can be provided. Therefore, the present spacer structure has an effect of providing a transfer tube with a small heat loss. Further, in the present embodiment, the case where a single bright surface cylindrical body 47 is inserted has been described. However, if a plurality of concentric multiple insertions are inserted, a spacer with further reduced heat loss can be provided.

[Example 5]

Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 7 shows a cross-sectional view of the transfer tube 6g of the spacer arrangement portion of the present invention.

The spacer of the fifth embodiment is different from the second embodiment in that the protective ring 48 provided on the outer periphery of the plastic spongy body 39 is a polygonal pentagonal cylinder. The other points are basically the same as in the second embodiment.

According to the structure of the spacer according to the present embodiment, the conduction heat transfer distance in the spongy body 39 serving as a heat entrance path from the contact portion C to the contact portion A point on the inner peripheral surface of the protective ring 48 and the vacuum pipe 4v is implemented. Since the length is longer than that in the case of Example 2, the amount of heat transfer in the heat transfer path is further reduced, and a spacer with reduced heat loss can be provided. Therefore, the present spacer structure has an effect of providing a transfer tube with a small heat loss.

[Example 6]

Next, a sixth embodiment of the present invention will be described with reference to FIG. The figure shows a longitudinal sectional view of the transfer tube 6g of the spacer arrangement portion of the present invention.

In the spacer of the sixth embodiment, the brightness of a plastic film 38 such as a polyester film or polyimide disk-shaped plastic film in which aluminum or gold having a low emissivity is vapor-deposited on one side or both sides is formed on the side surface of the plastic sponge-like body 38. The point that the surface reflecting film 49 is disposed and at least a part of the contact surface with the spongy body 38 is fixed and supported with an adhesive or the like is different from the first embodiment. This is basically the same as the first embodiment.

According to the structure of the spacer according to the present embodiment, it is possible to provide a spacer that reduces the amount of heat penetration by reflecting the radiant heat entering from the side surface of the spongy body 38 with the arranged bright surface reflecting film 49 and reducing the heat loss. Become. Therefore, the present spacer structure has an effect of providing a transfer tube with a small heat loss.

[Example 7]

Next, a seventh embodiment of the present invention will be described with reference to FIGS. FIG. 9 is a longitudinal sectional view of the transfer tube 6g of the spacer arrangement portion of the present invention, and FIG. 10 is a sectional view taken along arrow YY in FIG. However, the vacuum bellows tube is not shown.

The spacer of the seventh embodiment is different from the spacer of the above embodiment in that the spacer can be divided into two in the vertical direction on the paper surface so as to sandwich the forward tube 4f and the blade 4b. This point is basically the same as in the second embodiment.

The plastic spongy bodies 50u and 50d divided into two on the top and bottom of the paper are divided into two on the top and bottom of the inner peripheral protection rings 51u and 51d made of, for example, stainless steel, aluminum or plastic, which are divided into two on the top and bottom of the paper. It is sandwiched between outer peripheral protective rings 52u and 52d made of stainless steel, aluminum or plastic to constitute a spacer. As shown in FIG. 9, the side surfaces of the spongy bodies 50u, 50d are supported by the flanges 53u, 53d at both ends of the inner periphery protection rings 51u, 51d and the flanges 54u, 54d at both ends of the outer periphery protection rings 51u, 51d. Prevents moving in the direction.

As for the method of assembling the spacer, first, one or several bright surface films 57 made of, for example, a polyester film or a polyimide plastic film obtained by evaporating aluminum or gold on one side or both sides with a low emissivity to prevent radiant heat intrusion. Inner peripheral protection rings 51u, 51d are set so as to sandwich the wound blade 4b of the wound forward pipe 4f, and both ends thereof are tied with a stainless steel thin wire 55 to fix the inner peripheral protection rings 51u, 51d. At this time, the joint may be integrated by an adhesive or partial welding. Thereafter, the spongy bodies 50u, 50d are arranged, the outer peripheral protection rings 51u, 51d are set on the outer peripheral portions thereof, and both end portions thereof are bound by the thin stainless steel wires 56 to fix the inner peripheral protective rings 51u, 51d. At this time, the joint may be integrated by an adhesive or partial welding. Moreover, you may fix with a band with a screw fastening structure like a hose band instead of a thin wire | line. Further, instead of thin wires, tabs with bolt through holes (not shown) at the joint may be integrated with the upper and lower protective rings, and the protective rings may be fastened with bolts.

According to the structure of the spacer according to the present embodiment, since the spacer can be mounted in a divided manner, it can be mounted without damaging the vapor deposition film of the bright surface film 57 as compared with the case where a cylindrical spacer is inserted. It is possible to provide a spacer that can prevent intrusion of radiant heat into the blade 4b and reduce heat loss. Therefore, the present spacer structure has an effect of providing a transfer tube with a small heat loss.

[Example 8]

Next, an eighth embodiment of the present invention will be described with reference to FIG. FIG. 11 shows a cross-sectional view of the transfer tube 58 of the spacer arrangement portion of the present invention.

In the spacer of the eighth embodiment, the forward tube 4f, its blade 4b, the return tube 5f, and its blade 5b are supported in the transfer tube 58 in the inner peripheral hole 61 of the plastic spongy body 60, and the spongy body. The point 60 is arranged in the vacuum pipe 59v of the metal bellows pipe is different from the spacer of the above embodiment, and the other points are basically the same as those of the second embodiment. A blade 59vb is provided on the outer periphery of the vacuum pipe 59v.

According to the structure of the spacer according to the present embodiment, since the round trip tube can be arranged in one transfer tube, the total number of arranged spacers can be reduced to about half compared to the case where the transfer tube is provided separately for the forward path and the return path. A spacer with reduced heat loss can be provided. Therefore, the present spacer structure has an effect of providing a transfer tube with a small heat loss. In the present embodiment, the case where the inner peripheral hole 61 has a quadrangular shape has been described. However, when the transfer tube is bent with a triangular shape or a circular shape including a round-trip pipe, both flow paths are not restricted in the inner peripheral hole. The same effect is produced even when the movement is enabled.

In the above embodiment, the spacer of the present invention is described as an example applied to a transfer tube. When the vacuum heat insulating low-temperature device is a transfer tube and the object to be held is a cooling refrigerant transfer pipe, the spacer According to the structure, when vibration of the fluid flowing in the cooling refrigerant transfer pipe or mechanical vibration of the refrigerator for cooling the refrigerant occurs, the vibration is absorbed by the elastic function of the spongy body, and the cooling refrigerant transfer pipe It is possible to prevent the laminated heat insulating material wrapped around the spacer from rubbing against the inner periphery of the spacer, damage the deposited film, etc., increasing the radiation rate and increasing the amount of radiant heat penetration. It is possible to provide a heat insulating support spacer with a small heat loss that is kept small and prevents heat penetration due to radiant heat.

In the above embodiment, the case where the object to be cooled of the low-temperature cooling device is a superconducting bulk body constituting a superconducting magnet has been described. However, the body to be cooled constitutes a superconducting coil winding body and a superconducting power transmission device constituting the superconducting magnet. However, the same effect can be obtained even in a vacuum insulated low-temperature device such as a superconducting wire arranged in a long length in a heat insulating refrigerant transfer tube, a SQUID element of a magnetic measuring device, an electronic element of a computer, or a coil for NMR reception / irradiation. Produce an effect.

In the above embodiments, the case where the refrigerant is high-pressure helium gas has been described. However, even if the refrigerant to be transferred is a liquefied gas such as liquid nitrogen in a low temperature state, a vacuum heat insulating low temperature apparatus in which a heat insulating support spacer is arranged. In the low-temperature fluid transfer tube, the same action and effect are produced.

In the above embodiment, the spacer disposed on the transfer tube has been described. However, for example, in a heat insulating support material for holding a high-temperature superconducting current lead wire of a superconducting magnet or a SQUID element in a vacuum heat insulating low-temperature device incorporating a superconductor. Even when the heat insulating support spacer of the present invention is used, the same action and effect are produced in a vacuum heat insulating low temperature apparatus having a heat insulating function of a spacer having a small heat loss.

In the above embodiment, the case where the shell constituent member in the foam-like shell structure made of polyimide is used as the plastic sponge-like body, but polyimide, etc., instead of the foam-like shell structure is described. Even if the plastic three-dimensional fibrous net structure and appearance are composed of a soccer ball laminate structure, it has a heat insulating function with a small heat loss and produces the same action and effect in the heat insulating support spacer. .

Further, in the above embodiment, the case where the shell constituent member in the foam-like shell structure made of polyimide is used as the plastic sponge-like body, but instead, fine ventilation cavities such as activated carbon particles and zeolite particles are used. In the case of a laminated adhesive body of gas adsorbents having the same, it is possible to provide a spacer having a small heat loss with the same action and effect, and the activated carbon is used as the residual gas in the vacuum space where the spacer is arranged at the low temperature portion of the laminated adhesive body. Adsorption, further lowering the vacuum pressure, improving the vacuum heat insulating performance, and further providing an effect of providing a heat insulating support spacer with a small heat loss.

As mentioned above, according to the heat insulation support spacer in the vacuum heat insulation low temperature apparatus which becomes this invention, it is excellent in heat insulation by comprising a part of heat insulating material with a spongy spongy body, and the vacuum heat insulation low temperature equipment which reduces heat loss There is an effect that a heat insulating support spacer can be provided.

DESCRIPTION OF SYMBOLS 1 ... Superconducting bulk magnet, 2 ... Adiabatic vacuum container, 3 ... High temperature superconducting bulk body, 4b ... Blade, 4f ... Outward pipe, 4v ... Vacuum pipe, 5b, 5f ... Return pipe, 5v ... Vacuum pipe, 6g ... Transfer tube 6b ... Blade, 6h ... Transfer tube, 7 ... External magnet for magnetization, 8 ... Cooling stage, 9 ... Sleeve, 11 ... Vacuum vessel, 12 ... Screw heat exchanger, 13 ... Cooling stage, 14 ... Helium low temperature Refrigerator 15 ... Compressor 16 ... Countercurrent heat exchanger 19 ... Vacuum space 38 ... Spacer 39 ... Spongy body 40 ... Protective ring 41 ... Protective ring 42 ... Protective ring 45 ... Link Ring, 46 ... Connection ring, 47 ... Bright surface cylindrical body, 48 ... Protection ring, 50u, 50d ... Spongy body, 51u, 51d ... Inner periphery protection ring, 52u, 52d ... Outer periphery protection ring, 57 ... Bright surface film, 58 ... Tiger Scan fur tube male flange, 59V ... vacuum pipe, 60 ... spongy body, 61 ... inner peripheral hole.

Claims (10)

A vacuum heat insulating low temperature apparatus having a heat insulating function, wherein at least one low temperature object to be held is built in a vacuum pipe, and is disposed in a gap in a vacuum space between the object to be held and a vacuum member, and It has a spacer for holding the mutual positional relationship between the holding body and the vacuum pipe, and at least a part of the spacer is composed of a spongy body having no residual gas inside in the vacuum space. Insulation support spacer in vacuum insulation low temperature equipment. The vacuum adiabatic low temperature according to claim 1, wherein the spacer includes a ring body having a density higher than that of the sponge-like body at least on an inner peripheral portion and an outer peripheral portion of the sponge-like body. Insulation support spacer in equipment. 2. The structure according to claim 1, wherein one or a plurality of bright surface cylinders smaller than the emissivity of the sponge-like body are provided between the outer peripheral portion and the inner peripheral portion of the spacer. The heat insulation support spacer in the vacuum heat insulation low-temperature apparatus of Claim 2. The heat insulation in the vacuum heat insulation low-temperature equipment according to claim 1, 2 or 3, wherein at least one of the outer peripheral portion and the inner peripheral portion of the spacer is formed in a polygonal shape. Support spacer. The heat insulating support spacer in the vacuum heat insulating low temperature apparatus according to claim 1, wherein the contact curved surface portion of the spongy body and the ring body is not integrated. The luminescent surface cylinder smaller than the emissivity of the sponge-like body is provided on the side surface of the spacer on at least one side surface. The heat insulation support spacer in the vacuum heat insulation low temperature apparatus of Claim 4 and Claim 5. The spacer is divided so that the object to be held can be sandwiched and attached, and the ring bodies arranged on the inner periphery and the outer periphery that hold the divided spongy body are integrated by a fastening means after combining. The heat insulating support spacer in the vacuum heat insulating low temperature apparatus according to claim 2, 3, 4, 4, 5 and 6. In the vacuum space of the said vacuum member, the to-be-held body from which temperature differs is incorporated, The said to-be-held body is hold | maintained by the said spacer in the same spacer inner peripheral part, It is comprised. The heat insulation support spacer in the vacuum heat insulation low temperature apparatus of Claim 2, Claim 3, Claim 4, Claim 5, Claim 6 and Claim 7. The said vacuum adiabatic low temperature apparatus is a transfer tube which transfers a cooling refrigerant adiabatically, The claim 1, 2, 3, 4, 5, 6, 7. And a heat insulating support spacer in the vacuum heat insulating low temperature apparatus according to claim 8. The said sponge-like body is a gas adsorbent having a fine ventilation cavity, The claim 1, the claim 2, the claim 4, the claim 5, the claim 6, the claim 7, The heat insulation support spacer in the vacuum heat insulation low-temperature apparatus of Claim 8 and Claim 9.