JP5757986B2 - Cryogenic cable termination connection - Google Patents

Description

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

Conventionally, a superconducting cable using a superconducting wire that becomes a superconducting state at an extremely low temperature as a conductor is known. The superconducting cable is expected as a power cable capable of transmitting a large current with a low loss, and is being developed for practical use.
The superconducting cable has a structure in which a single-core or multiple-core cable core is accommodated in a heat insulating tube. The cable core includes, for example, a former, a superconducting conductor layer, an electrical insulating layer, a cable shield layer, and a protective layer in order from the center. The heat insulation pipe includes an inner pipe (hereinafter referred to as “heat insulation inner pipe”) in which the cable core is accommodated and filled with a refrigerant (for example, liquid nitrogen), and an outer pipe (hereinafter referred to as “heat insulation outer pipe”) covering the outer periphery of the heat insulation inner pipe. Have Between the heat insulating inner tube and the heat insulating outer tube, a vacuum state is set for heat insulation.

  In the terminal connection part of the superconducting cable, the terminal part of the superconducting cable is accommodated in a low temperature container that is a low temperature part, and the conductor of the superconducting cable (for example, the superconducting conductor layer) is drawn out to the room temperature part through the conductor lead-out part. The cryogenic container has a double structure comprising a refrigerant tank that houses the terminal portion of the superconducting cable and is filled with a refrigerant such as liquid nitrogen during operation, and a vacuum tank that accommodates the refrigerant tank and is in a vacuum state during operation ( For example, Patent Documents 1 and 2). The heat insulation inner pipe of the superconducting cable is connected to the refrigerant tank, and the heat insulation outer pipe is connected to the vacuum tank. The refrigerant tank is installed in the vacuum tank by an appropriate method (for example, suspended in a vacuum container in Patent Document 2).

  Here, since the superconducting cable connected to the refrigerant tank is long and laid in a twisted state, the torque around the axis applied to the refrigerant tank increases when the superconducting cable contracts due to cooling. This torque may cause the refrigerant tank to rotate around the axis. Therefore, in Patent Document 3, a rotation prevention mechanism for preventing the rotation of the refrigerant tank is provided in a low temperature container for housing a superconducting winding for a porcelain resonance (NMR) imaging apparatus. Specifically, by arranging at least three support ties so as to be symmetrical between the inner container (corresponding to the refrigerant tank) and the outer container (corresponding to the vacuum tank), the inner container is rotated around the axis. To prevent it from rotating.

Japanese Patent No. 4778452 Japanese Patent No. 4096360 Japanese Patent Publication No.2-60043

  However, in the structure of the support tie described in Patent Document 3, the inner container can be prevented from rotating, but when the inner container is thermally contracted in the axial direction as the refrigerant is charged, a shearing force is generated in the support tie. As a result, the support tie may be damaged.

  An object of the present invention is to provide a terminal connection portion of a cryogenic cable that can prevent the refrigerant tank from rotating about its axis and can also cope with thermal contraction in the axial direction of the refrigerant tank.

The terminal connection part of the cryogenic cable according to the present invention is a terminal part of the cryogenic cable,
A conductor lead-out portion connected to the conductor of the cryogenic cable and pulling out an electric current;
A refrigerant tank that houses a terminal portion of the cryogenic cable and into which refrigerant is introduced during operation;
A vacuum chamber that houses the refrigerant tank and is in a vacuum state during operation;
A support portion that connects and supports the refrigerant tank and the vacuum tank in the axial direction,
The support portion includes a plurality of fixed shafts that connect one end side in the axial direction of the refrigerant tank and one end side in the axial direction of the vacuum tank,
The refrigerant tank has a first flange portion in which a fixed shaft insertion hole for inserting the fixed shaft is formed,
The vacuum chamber has a fixed shaft locking portion at a position facing the fixed shaft insertion hole,
An axial one end side of the fixed shaft is fixed to the fixed shaft locking portion, and an axial other end side is fixed to the first flange portion through the fixed shaft insertion hole ,
The support part includes a sliding shaft that connects the other axial end of the refrigerant tank and the other axial end of the vacuum tank,
The refrigerant tank has a second flange portion in which a sliding shaft insertion hole for inserting the sliding shaft is formed,
The vacuum chamber has a sliding shaft locking portion at a position facing the sliding shaft insertion hole,
The other axial end of the sliding shaft is fixed to the sliding shaft locking portion, and the one axial end is slidably fixed to the second flange portion through the sliding shaft insertion hole. characterized in that that.

  According to the present invention, it is possible to prevent the refrigerant tank from rotating around the axis and to cope with thermal contraction in the axial direction.

It is a figure which shows the termination | terminus connection part which concerns on one embodiment of this invention. It is a figure which shows the connection structure of the refrigerant | coolant tank and vacuum tank in the front end side. It is a figure which shows the connection structure of the refrigerant | coolant tank and vacuum tank in a rear end side.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing a termination connection unit 1 according to an embodiment of the present invention. For convenience of explanation, the side on which the cryogenic cable 10 is introduced will be described as the rear end side (right side in FIG. 1), and the opposite side will be described as the front end side (left side in FIG. 1).

  As shown in FIG. 1, the terminal connection portion 1 includes a terminal portion of the cryogenic cable 10, a cryogenic container 20, a conductor extraction portion 30, a shield energization portion 40, a soot tube 50, and the like. The terminal portion of the cryogenic cable 10 is accommodated in a predetermined state in the cryogenic container 20 (specifically, the refrigerant tank 21), and the conductor current of the cryogenic cable 10 is transferred to the actual system side such as a power device via the conductor lead-out portion 30. Pulled out.

  The cryogenic cable 10 is a single-core superconducting cable in which a single cable core 11 is accommodated in a heat insulating tube 12. Note that the cryogenic cable 10 may be a three-core three-phase superconducting cable accommodated in the heat insulating tube 12 in a state where three cable cores 11 are twisted together.

  The cable core 11 includes, for example, a former 111, a superconducting conductor layer 112, an electrical insulating layer 113, a cable shield layer 114, a protective layer 115, and the like in order from the center.

  In the terminal portion of the cryogenic cable 10, the cable core 11 is stepped and the layers are exposed in order from the tip side. A conductor connection terminal 13 that is electrically connected to the superconducting conductor layer 112 is disposed on the outer periphery of the superconducting conductor layer 112. A shield connection terminal 14 that is electrically connected to the cable shield layer 114 is disposed on the outer periphery of the cable shield layer 114. An electric field relaxation layer 15 such as a stress cone is disposed on the outer periphery of the electrical insulating layer 113 located between the conductor connection terminal 13 and the shield connection terminal 14.

The heat insulating tube 12 has a double tube structure including an inner heat insulating inner tube 121 and an outer heat insulating outer tube 122.
The heat insulating inner pipe 121 accommodates the cable core 11 and is filled with a refrigerant (for example, liquid nitrogen) during operation. Thereby, the superconducting conductor layer 112 is maintained in a superconducting state. A space between the heat insulating inner pipe 121 and the heat insulating outer pipe 122 is kept in a vacuum state during operation for heat insulation.

The cryogenic container 20 has a double structure including an inner refrigerant tank 21 and an outer vacuum tank 22.
The refrigerant tank 21 has a hollow cylindrical shape, for example, and accommodates the terminal portion of the cryogenic cable 10. The refrigerant tank 21 has a conductor outlet 21 </ b> A for introducing the conductor extraction portion 30 and a shield outlet 21 </ b> B for introducing the shield energization portion 40.

  The end of the cryogenic cable 10 is introduced into the refrigerant tank 21 from the rear end side. The heat insulation inner pipe 121 of the cryogenic cable 10 is connected to the rear end portion 212 of the refrigerant tank 21. The refrigerant is circulated and supplied to the refrigerant tank 21 by a refrigerant circulation device (not shown) during operation. The inside of the heat insulating inner pipe 121 communicating with the refrigerant tank 21 is also filled with the refrigerant.

  An insulating spacer 62 is disposed at the conductor outlet 21 </ b> A of the refrigerant tank 21 in close contact with the conductor extraction portion 30 and the outer surface of the refrigerant tank 21. The insulating spacer 62 is made of, for example, epoxy resin or fiber reinforced plastics (FRP). A lid 63 is disposed at the shield outlet 21 </ b> B of the refrigerant tank 21 in close contact with the outer surface of the refrigerant tank 21. The refrigerant tank 21 and the vacuum tank 22 are partitioned by the insulating spacer 62 and the lid 63, and the refrigerant tank 21 is sealed airtight and watertight.

  Further, the front end 211 of the refrigerant tank 21 is connected to the front end 221 of the vacuum tank 22 by a plurality of fixed shafts 71 arranged in the axial direction. The rear end portion 212 of the refrigerant tank 21 is connected to the rear end portion 222 of the vacuum chamber 22 by a plurality of sliding shafts 72 arranged in the axial direction. The connection structure by the fixed shaft 71 and the sliding shaft 72 will be described later.

  The vacuum chamber 22 has, for example, a hollow cylindrical shape, and includes a vacuum chamber main body portion 22A that houses the refrigerant tank 21, a first cylindrical portion 22B that hangs upward from the vacuum tank main body portion 22A, and a first The second cylindrical portion 22C is provided so as to be spaced upward from the vacuum chamber main body portion 22A and spaced apart from the cylindrical portion 22B. In general, the first cylindrical portion 22B and the second cylindrical portion 22C are called temperature gradient portions.

  In the vacuum chamber 22, the conductor outlet 21A is positioned below the first cylindrical portion 22B, and the shield outlet 21B is positioned below the second cylindrical portion 22C. The refrigerant tank 21 is arranged. A heat insulating outer tube 122 of the cryogenic cable 10 is connected to the rear end portion 222 of the vacuum chamber 22.

The conductor lead-out portion 30 is disposed on the first tubular portion 22B, and the soot tube 50 is disposed on the upper portion of the first tubular portion 22B. In the second cylindrical portion 22C, a measurement pipe 61 for introducing sensors of various instruments (for example, a liquid level gauge, a thermometer, a pressure gauge, etc.) and a shield energizing section 40 are arranged in the refrigerant tank 21. The
Since the conductor outlet 21A and the shield outlet 21B of the refrigerant tank 21 are accommodated in the vacuum tank body 22A of the vacuum tank 22, the conductor extraction part 30, the shield energization part 40, and the measurement pipe 61 serving as a heat transfer path are The vacuum chamber body 22A is introduced into the interior. In order to reduce heat intrusion, it is necessary to secure a heat transfer path length. However, the temperature of the conductor outlet 21 </ b> A and the shield outlet 21 </ b> B of the refrigerant tank 21 is accommodated in the vacuum tank body 22 </ b> A of the vacuum tank 22. Since it becomes easy to ensure the heat transfer path length by the gradient part, the height of the first cylindrical part 22B and the second cylindrical part 22C can be kept low. Therefore, it is possible to reduce the size of the terminal connection portion 1.

  The vacuum chamber 22 is evacuated by a vacuum pump (not shown) during operation and kept in a vacuum state. The space between the heat insulating inner tube 121 and the heat insulating outer tube 122 communicating with the vacuum chamber 22 and the inside of the soot tube 50 are also maintained in a vacuum state.

  The conductor lead-out part 30 is a conductor for drawing a current from the cryogenic cable 10 to the actual system. The conductor lead part 30 has a conductor lead bar made of, for example, a copper bar or a pipe. In addition, the structure of the conductor extraction part 30 is not limited to this, A well-known structure is applicable. One end of the conductor lead-out portion 30 (conductor lead-out rod) is airtightly penetrated through the vertical tube 50 and drawn out to the outside, and the other end is connected to the conductor connection terminal 13. The conductor lead-out part 30 is electrically connected to the superconducting conductor layer 112 of the cryogenic cable 10 via the conductor connection terminal 13.

  The conductor lead-out part 30 preferably has at least a flexible conductor (not shown) such as a flat knitted copper wire. Thereby, even if the position of the conductor connection terminal 13 moves in the horizontal direction (left and right direction in FIG. 1) due to the thermal expansion and contraction of the cryogenic cable 10, it can easily follow, so that the insulation spacer 62 and the like can be damaged. Can be prevented.

  The shield energization unit 40 is a conductive member for grounding the cable shield layer 114 of the cryogenic cable 10. The configuration of the shield energization unit 40 is substantially the same as the configuration of the conductor extraction unit 30. That is, the shield energization unit 40 includes a shield lead bar made of, for example, a copper bar or a pipe. In addition, the structure of the shield energization part 40 is not limited to this, A well-known structure is applicable. One end of the shield energization part 40 (shield lead bar) is hermetically penetrated through the second cylindrical part 22C of the vacuum chamber 22 and drawn to the outside, and the other end is connected to the shield connection terminal 14. The shield energization unit 40 is electrically connected to the cable shield layer 114 of the cryogenic cable 10 via the shield connection terminal 14.

  The shield energizing section 40 preferably has a flexible conductor (not shown) such as a flat knitted copper wire at least partially. Thereby, even if the position of the shield connection terminal 14 moves in the horizontal direction (left and right direction in FIG. 1) due to the thermal expansion and contraction of the cryogenic cable 10, it is possible to easily follow, thereby preventing damage to the lid 63 and the like. it can.

The soot tube 50 has a polymer sleeve 51 and a shielding fitting 52.
The polymer sleeve 51 includes an insulating cylinder 51a and a polymer cover 51b. The insulating cylinder 51a is made of FRP (fiber reinforced plastic) having high mechanical strength. The polymer covering 51b is made of a material having excellent electrical insulation performance, for example, a polymer material such as silicone polymer (silicone rubber). The polymer cover 51b is provided on the outer periphery of the insulating cylinder 51a, and a plurality of umbrella-shaped ridges are formed on the outer peripheral surface of the polymer cover 51b so as to be separated in the longitudinal direction. The inside of the polymer sleeve 51 (inside the insulating cylinder 51a) is hollow.

  The shielding metal fitting 52 has a cylindrical portion 52a embedded concentrically with the polymer sleeve 51, and a flange portion 52b extending radially outward from the lower end of the cylindrical portion 52a. The cylindrical portion 52a has an electric field relaxation function, and relaxes the electric field of the soot tube 50.

  By placing the soot tube 50 on the upper part of the first cylindrical portion 22B of the vacuum chamber 22 and connecting the flange portion 52b of the shielding metal fitting 52 with a connecting member (not shown) such as a bolt, the soot tube 50 is in the vacuum chamber 22. To be airtightly fixed. The inside of the soot tube 50 communicates with the first cylindrical portion 22B and is in a vacuum state during operation. Thereby, since a vacuum heat insulation part can be ensured largely, the heat penetration | invasion from the outside through the conductor extraction | drawer part 30 can be reduced.

  As described above, the terminal connection portion 1 of the cryogenic cable 10 is connected to the terminal portion of the cryogenic cable 10 and the superconducting conductor layer 112 (conductor layer) of the cryogenic cable 10, and the conductor lead-out portion 30 that extracts current to the outside. A refrigerant tank 21 that accommodates the terminal portion of the cryogenic cable 10 and into which refrigerant is introduced during operation, a vacuum tank 22 that accommodates the refrigerant tank 21 and is evacuated during operation, and the refrigerant tank 21 and vacuum tank 22 is provided with a fixed shaft 71 (support part) and a sliding shaft 72 (support part) which are connected to and supported in the axial direction.

  FIG. 2 is a view showing a connection structure of the refrigerant tank 21 and the vacuum tank 22 on the distal end side of the cryogenic container 20. 2A is a cross-sectional view along the radial direction passing through the fixed shaft 71A, and FIG. 2B is a plan view of the refrigerant tank 21 as viewed from the front end side. In FIG. 2B, the fixed shaft 71 is shown as fixed shafts 71A to 71C.

As shown in FIG. 2, the refrigerant tank 21 and the vacuum tank 22 are connected by three fixed shafts 71 </ b> A to 71 </ b> C. The three fixed shafts 71 </ b> A to 71 </ b> C are arranged at positions rotated by 120 ° on the concentric circumference.
Note that the number of the fixed shafts 71 is not limited to three, and may be plural. For example, when the refrigerant tank 21 and the vacuum tank 22 are connected by two fixed shafts 71, it is preferable to arrange the refrigerant tank 21 and the vacuum tank 22 at a position rotated by 180 ° relative to the other. Further, from the viewpoint of preventing rotation around the axis of the refrigerant tank 21, it is preferable to configure the fixed shaft 71 with three or more.

  The fixed shaft 71 is made of an alloy material such as FRP or titanium, for example. In particular, the fixed shaft 71 is preferably made of FRP having a lower thermal conductivity than metal. Thereby, the heat penetration | invasion from the outside can be prevented effectively.

  The front end side of the refrigerant tank 21 is hermetically sealed by a plate-shaped front end portion 211 so that the refrigerant (for example, liquid nitrogen) in the refrigerant tank 21 does not leak out of the refrigerant tank 21. The refrigerant tank 21 has a flange portion 211a on the periphery of the front end portion 211 (hereinafter referred to as “front end side flange 211a”). A fixed shaft insertion hole 211b through which the fixed shaft 71 is inserted is formed in the distal end side flange 211a.

The front end side of the vacuum chamber 22 is hermetically sealed by a plate-shaped front end portion 221 in order to ensure the vacuum chamber 22 in a vacuum state. The vacuum chamber 22 has a fixed shaft locking portion 221a at a position facing the fixed shaft insertion hole 211b at the distal end portion 221. The fixed shaft locking portion 221a is a shaft insertion hole into which the distal end portion of the fixed shaft 71 is inserted, for example.
The fixed shaft locking portion 221a is preferably not penetrated in order to prevent vacuum leakage. When the fixed shaft locking portion 221a is not penetrated, there is no need to consider a vacuum leak, so there is no need to provide a seal member or the like, and the number of parts can be reduced. In addition, when taking an appropriate vacuum leakage countermeasure with a seal member or the like, the fixed shaft 71 may penetrate the fixed shaft locking portion 221a.

  The fixed shaft 71 is inserted into the fixed shaft insertion hole 211b and temporarily fixed to the distal end side flange 211a by the fixing member 73. The fixing member 73 is constituted by, for example, a nut that is tightened from both sides with the front end side flange 211a interposed therebetween. In the fixed shaft 71, a male screw is formed at a position corresponding to the nut 73 (fixing member) here, and the fixed shaft 71 and the nut 73 (fixing member) are screwed together. In this state, the distal end portion of the fixed shaft 71 is fixed to the fixed shaft locking portion 221a. For example, the distal end portion of the fixed shaft 71 is fixed by screwing with the fixed shaft locking portion 221a. Then, the tightening position of the nut 73 is adjusted, and the refrigerant tank 21 is positioned. Due to the shaft structure, the positioning operation of the refrigerant tank 21 is extremely easy.

Thus, in the termination | terminus connection part 1 of the cryogenic cable 10, the support part which connects and supports the refrigerant tank 21 and the vacuum tank 22 in an axial direction is the front end side (axial direction one end side) of the refrigerant tank 21, and a vacuum. A plurality of fixed shafts 71 that connect the tip end side (one axial end side) of the tank 22 are included.
The refrigerant tank 21 has a front end flange 211a (first flange portion) formed with a fixed shaft insertion hole 211b through which the fixed shaft 71 is inserted, and the vacuum tank 22 is located at a position facing the fixed shaft insertion hole 211b. A fixed shaft locking portion 221a is provided. And the front-end | tip part (axial direction one end side) of the fixed shaft 71 is fixed to the fixed shaft latching | locking part 221a, and the rear-end part (axial direction other end side) penetrates the fixed shaft penetration hole 211b, and is a front end side flange. It is fixed to 211a.

According to the terminal connection portion 1, it is possible to prevent the refrigerant tank 21 from rotating around the axis along with the thermal contraction of the cryogenic cable 10, and to cope with the thermal contraction of the refrigerant tank 21 in the axial direction. Can do.
For example, when the refrigerant tank 21 is thermally contracted in the axial direction, a tensile force may be applied in the axial direction of the fixed shaft 71. However, since the tensile strength of the fixed shaft 71 is greater than the shear strength, the possibility of breakage is extremely high. small. When the rear end 212 of the refrigerant tank 21 is movable in the axial direction as in the present embodiment, the thermal contraction in the axial direction of the refrigerant tank 21 is absorbed by the movement of the rear end 212. A difference in shrinkage between the tank 21 and the vacuum tank 22 can be absorbed.

  FIG. 3 is a diagram illustrating a connection structure of the refrigerant tank 21 and the vacuum tank 22 on the rear end side of the cryogenic container 20. 3A is a cross-sectional view along the radial direction passing through the sliding shaft 72A, and FIG. 3B is a plan view of the refrigerant tank 21 as seen from the rear end side. In FIG. 3B, the sliding shaft 72 is distinguished and shown as the sliding shafts 72A to 72C.

As shown in FIG. 3, the refrigerant tank 21 and the vacuum tank 22 are connected by three sliding shafts 72A to 72C. The three sliding shafts 72A to 72C are respectively arranged at positions rotated by 120 ° on the concentric circumference.
Note that the number of the sliding shafts 72 is not limited to three and may be plural. For example, when the refrigerant tank 21 and the vacuum tank 22 are connected by the two sliding shafts 72, the refrigerant tank 21 and the vacuum tank 22 are preferably arranged at a position rotated by 180 ° with respect to the other. Further, from the viewpoint of preventing the rotation of the refrigerant tank 21 around the axis, it is preferable that the sliding shaft 72 is composed of three or more.

  Similar to the fixed shaft 71, the sliding shaft 72 is made of an alloy material such as FRP or titanium. In particular, the sliding shaft 72 is preferably made of FRP having a lower thermal conductivity than metal. Thereby, the heat penetration | invasion from the outside can be prevented effectively.

  The rear end side of the refrigerant tank 21 is hermetically sealed by a plate-shaped rear end portion 212 so that the refrigerant (for example, liquid nitrogen) in the refrigerant tank 21 does not leak out of the refrigerant tank 21. The refrigerant tank 21 has a flange portion 212a on the periphery of the rear end portion 212 (hereinafter referred to as “rear end side flange 212a”). A sliding shaft insertion hole 212b through which the sliding shaft 72 is inserted is formed in the rear end side flange 212a.

The rear end side of the vacuum chamber 22 is hermetically sealed by a plate-shaped rear end portion 222 in order to ensure the vacuum chamber 22 in a vacuum state. The vacuum chamber 22 has a sliding shaft locking portion 222a at the rear end portion 222 at a position facing the sliding shaft insertion hole 212b. The sliding shaft locking portion 222a is a shaft insertion hole into which the rear end portion of the sliding shaft 72 is inserted, for example.
The sliding shaft locking portion 222a is preferably not penetrated in order to prevent vacuum leakage. When the sliding shaft locking portion 222a is not penetrated, it is not necessary to consider vacuum leakage, so there is no need to provide a seal member or the like, and the number of parts can be reduced. Note that when appropriate countermeasures against vacuum leakage are taken with a seal member or the like, the sliding shaft 72 may penetrate the sliding shaft locking portion 222a.

  The sliding shaft 72 is inserted into the sliding shaft insertion hole 212b in a state where the drop-off preventing member 74 is tightened on the distal end side. The drop-off prevention member 74 is constituted by, for example, a double nut. The drop-off prevention member 74 is a sliding shaft so that a gap d is formed between the rear end surface of the drop-off prevention member 74 (here, the rear end surface of the double nut) and the front end surface of the rear end portion 212 of the refrigerant tank 21. 72 is fixed. Further, the rear end portion of the sliding shaft 72 is fixed to the sliding shaft locking portion 222a. For example, the tip of the sliding shaft 72 is fixed by screwing with the sliding shaft locking portion 222a. The sliding shaft 72 is fixed to be slidable relative to the refrigerant tank 21.

Thus, in the termination | terminus connection part 1 of the cryogenic cable 10, the support part which connects and supports the refrigerant tank 21 and the vacuum tank 22 in an axial direction is a rear-end side (axial direction other end side) of the refrigerant tank 21. And a sliding shaft connecting the rear end side (the other end side in the axial direction) of the vacuum chamber 22.
The refrigerant tank 21 has a rear end side flange 212a (second flange portion) formed with a sliding shaft insertion hole 212b through which the sliding shaft 72 is inserted, and the vacuum tank 22 is formed in the sliding shaft insertion hole 212b. A sliding shaft locking portion 222a is provided at the opposing position. The rear end portion (the other end side in the axial direction) of the slide shaft 72 is fixed to the slide shaft engaging portion 222a, and the front end portion (the one end side in the axial direction) passes through the slide shaft insertion hole 212b. It is slidably fixed to the rear end side flange 212a.

  According to the terminal connection portion 1, since the sliding shaft 72 that prevents rotation around the axis is provided not only at the front end side but also at the rear end side, the refrigerant tank 21 is moved around the axis along with the thermal contraction of the cryogenic cable 10. It is possible to more effectively prevent the rotation. Further, since the heat shrinkage in the axial direction of the refrigerant tank 21 is absorbed by the rear end portion 212 of the refrigerant tank 21 sliding on the sliding shaft 72, the amount of contraction between the refrigerant tank 21 and the vacuum tank 22. Can be absorbed.

As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the above embodiment, and can be changed without departing from the gist thereof.
For example, the terminal connection portion 1 may have a connection structure by the fixed shaft 71 of the refrigerant tank 21 and the vacuum tank 22 on the front end side as described in the embodiment or on the rear end side. May be. When the connection structure by the fixed shaft 71 is provided on the rear end side, the connection structure by the sliding shaft 72 is provided on the front end side. Further, the terminal connection portion 1 may not have a connection structure with the sliding shaft 72.

  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.

DESCRIPTION OF SYMBOLS 1 Termination connection part 10 Cryogenic cable 11 Cable core 111 Former 112 Superconducting conductor layer 113 Electrical insulation layer 114 Cable shield layer 115 Protective layer 12 Thermal insulation pipe 121 Thermal insulation inner pipe 122 Thermal insulation outer pipe 13 Conductor connection terminal 14 Shield connection terminal 15 Electric field relaxation Layer 20 Cryogenic container 21 Refrigerant tank 21A Conductor outlet 21B Shield outlet 211 Tip 211a Tip flange (first flange)
211b Fixed shaft insertion hole 212 Rear end portion 212a Rear end side flange (second flange portion)
212b Sliding shaft insertion hole 22 Vacuum chamber 22A Vacuum chamber body 22B Tubular portion 22C Tubular portion 221 Tip portion 221a Fixed shaft locking portion 222 Rear end portion 222a Sliding shaft locking portion 30 Conductor lead portion 40 Shield energizing portion 50 Barrel 51 Polymer sleeve 51a Insulating cylinder 51b Polymer sheath 52 Barrier metal 52a Cylindrical part 52b Flange 61 Measurement pipe 62 Insulating spacer 63 Lid 71, 71A-71C Fixed shaft 72, 72A-72C Sliding shaft 73 Fixed member 74 Fall-off prevention member

Claims (6)

The end of the cryogenic cable,
A conductor lead-out portion connected to the conductor of the cryogenic cable and pulling out an electric current;
A refrigerant tank that houses a terminal portion of the cryogenic cable and into which refrigerant is introduced during operation;
A vacuum chamber that houses the refrigerant tank and is in a vacuum state during operation;
A support portion that connects and supports the refrigerant tank and the vacuum tank in the axial direction,
The support portion includes a plurality of fixed shafts that connect one end side in the axial direction of the refrigerant tank and one end side in the axial direction of the vacuum tank,
The refrigerant tank has a first flange portion in which a fixed shaft insertion hole for inserting the fixed shaft is formed,
The vacuum chamber has a fixed shaft locking portion at a position facing the fixed shaft insertion hole,
An axial one end side of the fixed shaft is fixed to the fixed shaft locking portion, and an axial other end side is fixed to the first flange portion through the fixed shaft insertion hole ,
The support part includes a sliding shaft that connects the other axial end of the refrigerant tank and the other axial end of the vacuum tank,
The refrigerant tank has a second flange portion in which a sliding shaft insertion hole for inserting the sliding shaft is formed,
The vacuum chamber has a sliding shaft locking portion at a position facing the sliding shaft insertion hole,
The other axial end of the sliding shaft is fixed to the sliding shaft locking portion, and the one axial end is slidably fixed to the second flange portion through the sliding shaft insertion hole. sealing end of the cryogenic cable, characterized in that that.   The terminal connection part of the cryogenic cable according to claim 1, wherein one end side in the axial direction of the fixed shaft is fixed to the fixed shaft engaging part without penetrating the vacuum chamber.   The terminal connection part of the cryogenic cable according to claim 1, wherein the fixed shaft is made of fiber reinforced plastic. The terminal connection portion of the cryogenic cable according to any one of claims 1 to 3, further comprising a drop-off preventing member at an end portion of the sliding shaft. The other axial end of the sliding shaft, pole according to any one of claims 1 to 4, characterized in that fixed to the slide shaft locking portion without penetrating the vacuum chamber Termination connection for low temperature cable. The terminal connection part of a cryogenic cable according to any one of claims 1 to 5 , wherein the sliding shaft is made of fiber reinforced plastic.

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