JP5555729B2 - Terminal equipment for cryogenic equipment - Google Patents

Description

  The present invention relates to a terminal device of a cryogenic device such as a superconducting cable.

  A terminal device of a cryogenic device such as a superconducting cable has a conductor lead bar, one end of which is electrically connected to the cryogenic device and the other end is drawn to a room temperature part. Since the conductor lead bar is usually made of copper, which is a good conductor of electricity and heat, heat flows from the room temperature region to the cryogenic region (that is, the cryogenic device) through this conductor lead bar. When the temperature of the cryogenic device rises above a predetermined temperature due to the inflow of heat, the superconducting characteristics are degraded. Therefore, in the terminal device of the cryogenic equipment, it is important to minimize the heat inflow through the conductor lead bar.

  For example, Patent Documents 1 to 3 disclose a configuration for suppressing heat inflow through the conductor extraction rod.

  In Patent Document 1, a vacuum heat insulating layer is provided around a conductor lead bar (conductor 2 in Patent Document 1), so that the peripheral surface of the conductor lead bar (conductor) is insulated from the normal temperature region. A configuration is disclosed. Thereby, since the amount of heat flowing from the periphery of the conductor extraction rod (conductor) can be reduced, the heat inflow to the cryogenic device (the cryogenic cable in Patent Document 1) through the conductor extraction rod (conductor) can be reduced.

  Patent Document 2 discloses a configuration in which heat flow from the outside to the cryogenic region can be further suppressed by installing the temperature gradient portion of the conductor lead bar (the lead conductor 47 in Patent Document 2) and the entire stress cone in a vacuum. It is disclosed. Further, Patent Document 2 discloses that a connection portion between a conductor lead bar (drawer conductor) and a cryogenic device (superconducting cable in Cited Document 2) is electrically insulated with liquid nitrogen having good electrical insulation, and a conductor lead bar. The temperature gradient portion of the (drawer conductor) is electrically insulated by a vacuum with a stress cone provided around the temperature gradient portion, thereby providing a cryogenic cable terminal connecting device capable of obtaining a stable electrical insulation performance with a compact configuration. A configuration is disclosed.

  In Patent Document 3, a conductor corresponding to a conductor extraction rod is inserted into a metal tube, and the inside of the metal tube is filled with a coolant or a gas, and a heat insulating layer is formed on the metal tube by a vacuum or a heat insulating material. Thus, a configuration for preventing the temperature rise of the conductor and damage to the stress cone is disclosed.

  Patent Document 4 discloses a terminal structure of a cryogenic device having a conductor extraction rod (conductor portion) drawn from a cryogenic portion to a room temperature portion, and the conductor extraction rod (conductor portion) includes a hollow pipe. A configuration in which a gas that does not liquefy at a very low temperature such as helium is filled in the sealed space is disclosed. Thereby, in patent document 4, it prevents that a liquefied material generate | occur | produces inside a bushing at cryogenic temperature, and prevents that insulation performance falls in connection with the negative pressure in the space and the space | gap part.

Japanese Utility Model Publication No. 2-30232 JP-A-8-196029 Japanese Utility Model Publication No. 54-8698 JP 2002-280628 A

  By the way, in the vacuum insulation type terminal connection device of the cryogenic cable disclosed in Patent Document 1, the stress cone has a structure in which the upper half of the stress cone is exposed to the atmosphere and the lower half is located in the cryogenic region. The heat inflow through is large, and it is difficult to sufficiently reduce the heat inflow from the outside. Further, since the temperature difference inside the stress cone is large, cracks due to thermal strain may occur in the stress cone, and there is a problem in terms of electrical insulation. Moreover, the stress cone of patent document 1 is a product made from rubber, and the flange is embedded in the stress cone made from rubber. For this reason, even if the metal flange is fixed to the cylindrical portion, the rubber is an elastic body, so that the mechanical characteristics may not be stabilized.

  Further, in the terminal connecting device for the cryogenic cable disclosed in Patent Document 2, the stress cone is not exposed to the atmosphere and is installed in a vacuum in a soot tube and a vacuum vessel. The heat inflow can be reduced. However, since the outer periphery of the stress cone is vacuum-insulated, the insulation performance is inferior to that of insulating oil, and therefore it is necessary to increase the creepage distance compared to the case of insulating oil. Moreover, it is necessary to provide a porcelain soot tube on the outer periphery of the stress cone. Therefore, there is a problem that the terminal device is increased in size. In addition, there is a problem that the number of parts is large and it takes time to assemble the terminal device.

  Moreover, in the terminal part of the cryogenic cable etc. of patent document 3, the generation | occurrence | production of the crack in the normal temperature area | region of a stress cone is prevented by inserting the braided string-like conductor equivalent to a conductor extraction rod into the inside of a metal pipe. Yes. However, similarly to Patent Document 2, a soot pipe is required on the outer periphery of the stress cone, and there is a problem that the terminal device is enlarged. There is also a problem that the number of parts is large and it takes time to assemble the terminal device.

  Moreover, in patent document 4, similarly to patent document 2 and patent document 3, it is necessary to provide an insulator (soot pipe) in the outer periphery of a bushing, and there exists a problem that a terminal device enlarges. Further, in Patent Document 4, the bushing is insulated by filling the insulator with insulating oil. However, when insulating the inside of the insulator with insulating oil, it is necessary to provide an air layer on the upper surface of the insulating oil so that the insulator is not damaged even if the insulating oil expands due to a ground fault or the like. Due to the presence of this air layer, heat inflow into the cryogenic region is still a problem. Moreover, it becomes complicated in terms of construction, such as the work of filling the insulating oil.

  In each of Patent Documents 2 to 4, since it is necessary to cover the outer pipe with the outer side, there is a configuration in which a gap exists between the outer periphery of the conductor extraction rod and the inner side of the vertical pipe. This gap is likely to be affected by heat via the conductor lead bar, and as a result, heat may flow into the cryogenic region.

In addition, in the case of a terminal device of a cryogenic device that insulates the inside of the soot pipe with an insulating gas such as SF ₆ gas, ancillary equipment that is managed by attaching a pressure gauge or the like is necessary so that the SF ₆ gas does not become negative pressure. Therefore, the number of parts increases correspondingly, and much cost is required for the terminal device of the cryogenic equipment.

  The present invention has been made in consideration of the above points, and an object of the present invention is to provide a terminal device having a simple and compact configuration capable of sufficiently suppressing heat inflow to a cryogenic device such as a superconducting cable.

One aspect of a terminal device for a cryogenic device according to the present invention is a terminal device for a cryogenic device having a conductor lead bar connected to the cryogenic device and drawn from the cryogenic region to the room temperature region. And an insulating tube made of an epoxy resin provided on the outer periphery of the conductor lead bar, and provided integrally with the outer periphery of the insulating tube, and a plurality of flanges are formed on the outer periphery of the insulating tube and spaced apart in the longitudinal direction. A polymer bushing, and a lower bushing portion made of the epoxy resin that is connected to the insulating cylinder, the insulating cylinder is disposed in a normal temperature region, and the lower bushing portion is disposed in a cryogenic region, the conductor pull-out is a hollow pipe, the lower end portion of the hollow pipe is exposed from the lower bushing portion, the portion of the exposure of the hollow pipe has a liquid nitrogen inlet, the lower bushing portion, Comprising a bell-mouth portion as the cryogenic region side shield to the lower end portion of the conductive layer surface, said insulating tube is embedded shielding metal fitting, the hollow portion of the hollow pipe, at least the lower end of said hollow pipe The liquid nitrogen is filled from a portion to a position corresponding to the bell mouth portion , and the liquid nitrogen is stored in the cryogenic region on the outer periphery of the lower bushing portion until the bell mouth portion is immersed .

  According to the present invention, since the conductor extraction rod that is a hollow pipe is cooled from the inside by liquid nitrogen, heat flows from the room temperature region to the cryogenic device through the hollow pipe (that is, the conductor extraction rod). Can be surely prevented. Moreover, since it is not the structure which covers a hollow soot tube conventionally, a compact terminal device is realizable. Therefore, it is possible to realize a terminal device having a simple and compact configuration that can sufficiently suppress heat inflow to the cryogenic equipment.

The figure which shows the structure of the superconducting cable terminal device which concerns on embodiment The figure which shows the structure of the superconducting cable terminal device of other embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a longitudinal sectional view showing a configuration of a superconducting cable terminal device as a terminal device of a cryogenic device according to an embodiment of the present invention. A superconducting cable terminal device 100 as a terminal device of a cryogenic device is connected to a superconducting cable 200 as a cryogenic device.

  The superconducting cable terminal device 100 includes a polymer sleeve 110, a connection part 120, a liquid nitrogen tank 130, and a vacuum tank 140.

  The connection portion 120 is a portion that electrically connects the conductor lead bar 111 of the polymer sleeve 110 and the superconducting cable 200. In this embodiment, connection portion 120 is a flexible connection conductor 121 for connecting to conductor lead bar 111, and conductor connection portion 122 for electrically connecting flexible connection conductor 121 and the conductor of superconducting cable 200. Is provided. The configuration of the conductor connecting portion 122 may be a known configuration. Liquid nitrogen 150 is stored in liquid nitrogen tank 130 by injecting liquid nitrogen 150 from piping 160. The liquid nitrogen tank 130 accommodates the lower end portion (lower bushing portion 117 described later) of the polymer sleeve 110, the connection portion 120, and the terminal end portion of the superconducting cable 200, and the amount of liquid nitrogen in which these portions are immersed. 150 are stored. Further, a vacuum tank 140 is provided outside the liquid nitrogen tank 130.

  The polymer sleeve 110 includes a conductor lead bar 111, an insulating cylinder 112, and a polymer cover 113. The conductor lead bar 111 is disposed at the center of the insulating cylinder 112, and its upper end is connected to the terminal portion T <b> 1 and its lower end is connected to the connection portion 120. The insulating cylinder 112 is provided on the outer periphery of the conductor lead bar 111. The polymer cover 113 is provided on the outer periphery of the insulating cylinder 112, and a plurality of flanges 113 a are formed on the outer periphery thereof so as to be separated along the longitudinal direction of the polymer cover 113.

  Here, the insulating cylinder 112 is formed of an epoxy resin having high mechanical strength. The polymer covering 113 is made of a material having excellent electrical insulation performance, for example, a polymer insulating material such as silicone polymer (silicone rubber). The conductor lead bar 111, the insulating cylinder 112 (and a lower bushing portion 117 described later), and the polymer cover 113 are integrally formed by a mold.

  Since the polymer sheath 110 is integrally provided on the outer periphery of the insulating cylinder 112, the polymer sleeve 110 is lighter and less likely to break than the conventional porcelain porcelain tube, and is easy to handle and workability. Can be greatly improved. Also, since no insulating oil or insulating gas is required, the environment can be harmonized. Furthermore, when the polymer sheath 113 is made of a silicone polymer, the polymer sleeve 110 can improve the fouling withstand voltage characteristics due to the water repellency of the silicone polymer.

  The polymer cannula 110 has a shielding fitting 114 in the present embodiment. The shield metal 114 is provided concentrically with the conductor lead bar 111. The shielding metal fitting 114 has a cylindrical portion 114a embedded in the insulating cylinder 112 so that only the outer surface is exposed from the insulating cylinder 112, and an embedded portion that is connected to the upper end of the cylindrical section 114a and embedded in the insulating cylinder 112. 114b and a flange portion 114c projecting radially outward from the peripheral surface of the cylindrical portion 114a.

  The upper end of the shielding metal fitting 114 (here, the upper end of the embedded portion 114b) is formed in a circular arc shape in cross section, whereby the concentration of the electric field in the polymer sleeve 110 is alleviated. The flange portion 114c is provided with a plurality of bolt holes (not shown), and a sealing material such as an O-ring (not shown) is provided on the lower surface of the flange portion 114c.

  In the present embodiment, the polymer cannula 110 is airtightly attached to the upper surface of the vacuum chamber 140 by inserting bolts (not shown) into the bolt holes of the flange portion 114c. Thereby, since the shielding metal fitting 114 (embedded portion 114b) is embedded in the insulating tube 112 formed of an epoxy resin having higher mechanical strength than rubber, it is embedded in the rubber stress cone of Patent Document 1. The polymer cannula can be attached in a mechanically stable state as compared with the case where it is fixed with a flange.

  Further, a liquid nitrogen tank 130 is formed inside the vacuum tank 140. In the present embodiment, the polymer cannula side end face of the liquid nitrogen tank 130 is airtightly fixed to the polymer cannula side inner end face of the vacuum tank 140 with a bolt or the like via a seal material such as an O-ring (not shown). As a result, the upper side of the flange portion 114c of the polymer sleeve 110 exists in the air, and the lower side of the flange portion 114c exists in the liquid nitrogen tank 130.

  In addition, what is necessary is just to form the other end side of the liquid nitrogen tank 130 by airtightly by the known structure to the predetermined part of cryogenic equipment (here superconducting cable 200). The same applies to the other end side of the vacuum layer 140. A vacuum state is maintained between the outer surface of the liquid nitrogen tank 130 and the inner surface of the vacuum tank 140.

  Furthermore, an electric field relaxation layer (not shown) may be formed at a necessary length at the interface between the insulating cylinder 112 and the polymer cover 113 so as to be in electrical contact with the shielding fitting 114 as necessary. This electric field relaxation layer may be formed of a high dielectric constant layer having a relative dielectric constant of 10 or more, such as a ZnO layer formed by filling an elastomer material with zinc oxide powder or a rubber filled with a conductive filler such as carbon black. . In the case where the polymer cannula 110 is applied to a terminal having a high voltage of 110 kV or higher, it is useful because the polymer cannula 110 can be made smaller by the electric field relaxation layer, and the polymer cannula 110 can be reduced in weight.

  The polymer sleeve 110 has a lower bushing portion 117 formed below the flange portion 114 c of the shielding metal fitting 114. In the present embodiment, the lower bushing portion 117 is disposed in the liquid nitrogen tank 130 when the polymer sleeve 110 is attached to the upper surface of the vacuum tank 140. The lower bushing portion 117 is connected to the insulating cylinder 112. The main body of the lower bushing portion 117 is integrally formed of the same epoxy resin as that of the insulating cylinder 112, and a conductor lead bar 111 is disposed at the center. The lower bushing portion 117 has a columnar portion 117a having a constant outer diameter, a truncated cone portion 117b having a smaller outer diameter toward the lower side, and a U-shaped cross section on the circumference of the upper end of the truncated cone portion 117b. A bell mouth portion 117c formed of a concave groove. In addition, a conductive layer 118 formed by applying a conductive paint such as silver paint is formed from the bell mouth portion 117 c to the lower surface of the fixed flange portion 114. The conductive layer 118 functions as a shielding layer for the lower bushing portion 117.

  The liquid nitrogen 150 is stored in the tank up to a position where the lower end of the conductive layer 118 where the electric field is concentrated (the end of the conductive layer 118 on the cryogenic device side) is immersed. Accordingly, the hollow portion 111 a of the hollow pipe 111 is filled with liquid nitrogen from at least the lower end portion of the hollow pipe 111 to a position corresponding to the lower end portion of the conductive layer 118 on the surface of the lower bushing portion 117. In the present embodiment, since the bell mouth portion 117c is the lower end portion of the conductive layer 118, the electric field in the lower bushing portion 117 is concentrated on the lower end portion of the bell mouth portion 117c. Therefore, in order to alleviate this electric field, the liquid nitrogen 150 is stored up to a position where the bell mouth portion 117c is immersed. Since the liquid nitrogen 150 has higher insulation performance than the vacuum insulation, the bellows part 117c where the electric field is concentrated can be immersed in the liquid nitrogen 150 to form an electrically stable lower bushing part 117.

  Further, the shield on the cryogenic region side where the liquid nitrogen 150 is stored is not a metal fitting (lower flange of the flange of Patent Document 1) as in Patent Document 1, but a bell mouth part 117c having a conductive layer 118 on the surface. Is formed. Since the difference in coefficient of linear expansion between the metal fitting forming the shielding metal fitting 114 and the epoxy resin forming the lower bushing portion 117 is large, the shielding layer 114 does not form the shielding on the extremely low temperature side, and the conductive layer is formed on the surface. By forming the bell mouth portion 117c provided with 118, damage to the epoxy resin can be prevented.

  In addition to this configuration, the conductor lead bar 111 includes at least a hollow portion 111a, and is formed of a conductive hollow pipe in the present embodiment. The conductor lead bar 111 is made of, for example, copper. One of the conductor lead bars 111 is exposed from the insulating cylinder 112, and the other is exposed from the lower bushing portion 117. In the present embodiment, a liquid nitrogen side connection portion 111c of the conductor lead bar 111 is provided at the lower end of the other conductor lead bar 111 so as to be connected to one terminal of the flexible connection conductor 121. The liquid nitrogen side connecting portion 111c of the conductor lead bar 111 in the present embodiment is a terminal by welding or the like with a gap (liquid nitrogen flowing portion 111d to be described later) passing through the lower end surface of the hollow pipe 111. Are integrated and formed.

  In addition, the structure of the liquid nitrogen side connection part 111c of the conductor extraction rod 111 is not limited to this, For example, you may electrically connect with the superconducting cable 200 by inserting a metal adapter in the hollow pipe 111. In this case, the lower end portion of the hollow pipe 111 is the liquid nitrogen side connection portion 111c. Further, a portion protruding from the lower bushing portion 117 at the lower end of the conductor lead bar 111 has a liquid nitrogen circulation portion 111d. The liquid nitrogen circulation portion 111d may have a configuration provided on the lower end surface of the hollow pipe 111 (a configuration in which liquid nitrogen flows simply from the lower end of the hollow portion 111a of the hollow pipe 111) or protrudes from the lower bushing portion 117 of the hollow pipe 111. The structure which provided the hole in the outer periphery of the part to perform may be sufficient.

  Further, the upper end of the conductor lead bar (hollow pipe) 111 is closed by a lid 111b, so that the hollow portion 111a is sealed. Thereby, in the hollow portion 111a of the conductor lead bar 111 which is a hollow pipe, the liquid nitrogen 150 exists at the lower position, and the vaporized nitrogen exists at the upper position. As a result, the conductor lead bar 111 is sufficiently cooled from the inside.

  Here, as can be seen from the figure, the upper side of the flange portion 114c of the shielding metal fitting 114 of the polymer sleeve 110 is disposed in the normal temperature region, but the conductor lead bar (hollow pipe) 111 is cooled from the inside. Therefore, it is possible to reliably prevent heat from flowing from the normal temperature region to the superconducting cable 200 in the extremely low temperature region through the conductor extraction rod (hollow pipe) 111.

Moreover, in the terminal device of the conventional cryogenic apparatus disclosed in Patent Documents 2 to 4, it was necessary to cover a porcelain porcelain tube outside the stress cone or bushing. The structure of the polymer cannula 110 integrally forming the polymer covering body 113 on the outer periphery of 112 eliminates the need for a soot tube, reduces the number of parts compared to a porcelain soot tube, and stabilizes electrical performance. An apparatus can be provided. In addition, unlike the conventional cryogenic equipment terminal device that covers the soot pipe outside the stress cone or bushing, in this embodiment, there is no gap between the outer circumference of the conductor lead bar and the inside of the soot pipe. Heat flow into the can be prevented. Thereby, the consumption of liquid nitrogen 150 can be suppressed. In addition, in the conventional soot pipe, it is necessary to fill an insulating medium such as insulating gas (SF ₆ gas) or insulating oil when assembling the terminal device. In this embodiment, the polymer covering 113 is disposed on the outer periphery of the insulating cylinder 112. Since the structure of the polymer sleeve 110 formed integrally is not necessary to fill the insulating medium, the assembly time of the terminal device can be shortened. In addition, when an insulating gas (SF ₆ gas) is sealed in a conventional soot pipe, there is no need for ancillary equipment required to manage the gas so that it does not become negative pressure. The cost to do can also be reduced.

  In this embodiment, in the room temperature region, a polymer sleeve having an electrically stable performance as air insulation is applied instead of a structure in which the stress cone is directly exposed to the atmosphere as in Patent Document 1. Therefore, it is possible to provide a cryogenic terminal device having electrically stable performance.

  Further, in the present embodiment, the longitudinal length of the cylindrical portion 117b of the lower bushing portion 117 is set to a predetermined space between the upper surface immersed in the liquid nitrogen 150 and the flange portion 114c of the polymer sleeve 110. The head is configured to the extent that it can. In this predetermined space, vaporized nitrogen is present in the same manner as the position above the liquid nitrogen portion of the hollow portion 111a of the conductor lead bar 111. In addition, when an apparatus for circulating liquid nitrogen is provided separately, the liquid nitrogen tank 130 may be filled with the liquid nitrogen 150 without providing a predetermined space. In the case of this embodiment, the temperature gradient from the extremely low temperature region to the normal temperature region in the polymer cannula 110 can be made gentle by the vaporized nitrogen in the predetermined space.

  As described above, the conductor extraction rod 111 is constituted by a hollow pipe, and the liquid nitrogen 150 is inserted into the hollow portion of the hollow pipe, so that the heat inflow to the superconducting cable 200 can be sufficiently suppressed. The cable terminal device 100 can be realized.

  In addition to the above-described embodiment, as shown in FIG. 2, a heat insulating layer 170 may be formed on the outer peripheral side of the conductor lead bar (hollow pipe) 111. The heat insulating layer 170 is formed from the upper end of the insulating cylinder 112 to the lower end of the lower bushing portion 117. In the embodiment of FIG. 2, the heat insulating layer 170 protrudes from the upper end of the insulating cylinder 112, and the lower end protrudes from the lower end of the lower bushing portion 117. The length of the heat insulating layer 170 in the longitudinal direction is shorter than the length of the conductor lead bar 111. In this way, heat inflow from the normal temperature region to the extremely low temperature region can be further suppressed through the conductor extraction rod (hollow pipe) 111, so that the consumption of liquid nitrogen 150 can be suppressed.

  In the present embodiment, a conductor lead bar (hollow pipe) 111 is inserted into the inner periphery of the inner metal tube 180, and an outer metal tube 190 having a larger diameter is concentric outside the inner metal tube 180. The space between the inner metal tube 180 and the outer metal tube 190 is hermetically closed up and down, and the internal air is discharged through the valve 300 to form a heat insulating layer 170 made of vacuum. In addition, even if it does not provide the valve 300, you may seal like a thermos in a vacuum state. In this case, it is good also as a structure which seals up and down between the outer metal tube 190 and the outer periphery of the conductor extraction rod 111, without providing the inner metal tube 180. FIG. Note that the heat insulating layer 170 is not limited to being formed by vacuum, but may be formed by filling a powdery heat insulating material and further evacuating.

  1 and 2, the concave and convex portions may be provided by a configuration in which a screw groove is cut in the entire inner length of the hollow pipe 111 (a so-called female screw configuration). Due to the uneven portion, the surface area of the inner surface of the hollow pipe 111 is increased, so that the efficiency of heat conduction is improved. Therefore, even if the entire hollow portion 111a of the conductor extraction rod 111 (hollow pipe) is not filled with the liquid nitrogen 150, the upper portion of the conductor extraction rod 111 is cooled more efficiently by the liquid nitrogen 150 at the lower end portion of the conductor extraction rod 111. can do. In addition, although it is more efficient in terms of processing when the uneven portion is provided in the entire length of the hollow pipe 111, from the viewpoint of a function to improve the efficiency of heat conduction, a portion filled with vaporized nitrogen (that is, the hollow pipe 111). A configuration in which a concavo-convex part is provided in a part) may be used.

  Further, in the above-described embodiment, when a part of the hollow portion 111a of the conductor extraction rod (hollow pipe) 111 is filled with the liquid nitrogen 150 (that is, the liquid nitrogen 150 exists at a position below the hollow portion 111a, Although the case where vaporized nitrogen exists in the upper position) has been described, the liquid nitrogen 150 may be filled in the entire hollow portion 111a. For example, by inserting an injection tube for injecting liquefied nitrogen 150 into the hollow portion 111a into the lid 111b and injecting liquefied nitrogen from the injection tube, the entire hollow portion 111a can be filled with the liquid nitrogen 150. .

  In the above-described embodiment, the upper portion of the conductor extraction rod (hollow pipe) 111 is provided with the lid 111b. However, by removing the lid 111b and providing another terminal device, the other terminal device is directed toward the other terminal device. The liquid nitrogen 150 may be circulated. Also in this case, the liquid nitrogen 150 is filled in the entire hollow portion 111a.

  In the above-described embodiment, the case where the polymer cannula 110 is fixed to the upper surface of the vacuum chamber 140 has been described. However, the upper end of the liquid nitrogen vessel 130 is configured to extend radially inward, and the polymer cannula is disposed on the upper end surface. 110 may be fixed.

  In the above-described embodiment, the case where the flange portion of the polymer sleeve 110 is formed by the flange portion 114c of the shielding metal fitting 114 has been described. However, the flange portion is formed by the insulating cylinder 112 and fixed from the outside by the fixing metal fitting. It is good also as composition to do.

  Furthermore, although the case where the present invention is applied as a terminal device for a superconducting cable has been described in the above-described embodiment, the present invention can also be used as a terminal device for cryogenic equipment other than a superconducting cable. Other cryogenic devices suitable for application of the present invention include, for example, superconducting magnetic energy storage (SMES), superconducting current limiters, and the like.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

100 Cable terminal device 110 Polymer sleeve 111 Conductor extraction rod (hollow pipe)
111a Hollow part 111b Lid 112 Insulating cylinder 113 Polymer covering body 114 Shield metal fitting 114a Cylindrical part 114b Embedding part 114c Flange part 117 Lower bushing part 117a Columnar part 117b Frustum part 117c Bell mouth part 118 Conductive layer 120 Connection part 130 Liquid nitrogen tank 140 Vacuum tank 150 Liquid nitrogen 170 Heat insulation layer 180 Inner metal pipe 190 Outer metal pipe 200 Superconducting cable 300 Valve

Claims (4)

A terminal device for a cryogenic device, which is connected to a cryogenic device and has a conductor lead bar drawn from a cryogenic region to a room temperature region,
A conductor lead bar;
An insulating cylinder made of an epoxy resin provided on the outer periphery of the conductor lead bar;
A polymer covering provided integrally with the outer periphery of the insulating cylinder, and formed with a plurality of flanges spaced apart in the longitudinal direction on its outer periphery;
A lower bushing made of the epoxy resin, connected to the insulating cylinder;
With
The insulating cylinder is disposed in a normal temperature region,
The lower bushing is disposed in a cryogenic region;
The conductor lead bar is a hollow pipe,
The lower end of the hollow pipe is exposed from the lower bushing,
The exposed portion of the hollow pipe has a liquid nitrogen inflow portion,
The lower bushing portion includes a bell mouth portion as a shield on the cryogenic region side at the lower end portion of the conductive layer on the surface,
A shielding fitting is embedded in the insulating cylinder,
The hollow part of the hollow pipe is filled with liquid nitrogen at least from the lower end part of the hollow pipe to a position corresponding to the bell mouth part ,
On the outer periphery of the lower bushing part, liquid nitrogen is stored in the cryogenic region up to a position where the bell mouth part is immersed,
Terminal equipment for cryogenic equipment. A heat insulating layer is provided between the epoxy resin and the conductor lead bar,
The terminal device of the cryogenic apparatus according to claim 1 . Concave and convex portions are formed on the inner surface of the hollow pipe,
The terminal device of the cryogenic device according to claim 1 or 2 . The cryogenic device is a superconducting cable,
The terminal device of the cryogenic device according to any one of claims 1 to 3 .

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