WO2006080280A1

WO2006080280A1 - Cryogenic fluid supply/discharge device and superconducting device

Info

Publication number: WO2006080280A1
Application number: PCT/JP2006/300980
Authority: WO
Inventors: Hidekazu Takahashi; Toshio Takeda
Original assignee: Eagle Industry Co., Ltd.; Ishikawajima-Harima Heavy Industries Co., Ltd.
Priority date: 2005-01-26
Filing date: 2006-01-23
Publication date: 2006-08-03
Also published as: TW200636181A; TWI349752B; JPWO2006080280A1; JP4602397B2

Abstract

A cryogenic fluid supply/discharge device for supplying/discharging a cryogenic fluid to/from a plurality of internal space channels (25) in the rotor assembly (20) of a superconducting motor (2) comprising a rotary joint shaft (32) and a rotary joint (30) having a casing (38), wherein the casing (38) is provided with fixed connection ports (52, 54) at a plurality of axial positions corresponding, respectively, to rotary communicating holes (66) and rotary ring holes (62), a rotary ring (60) is secured to the outer circumference of the rotary joint shaft (32) at the position of every other rotary interconnection hole (66) in the axial direction, and portions of the rotary joint shaft (32) and the rotary ring (60), and a part of the casing provided with the fixed connection openings (50, 52, 54, 56) to come into contact with a cryogenic fluid are made of FRP exhibiting an excellent thermal insulation as compared with metal. The cryogenic fluid supply/discharge device exhibits an excellent thermal insulation and minimizes leakage of the cryogenic fluid to the outside.

Description

Cryogenic fluid supply / discharge device and superconducting device

Technical field

[0001] The present invention relates to a cryogenic fluid for supplying and discharging a cryogenic fluid such as liquid nitrogen or liquid helium to a portion requiring cooling through a rotating shaft of a rotating machine such as a superconducting motor. The present invention relates to a fluid supply / discharge device and a superconducting device using the device. More specifically, it has excellent heat insulation, minimizes leakage of cryogenic fluid to the outside, and is compact with very little power loss. In addition, the present invention relates to a low-cost cryogenic fluid supply / discharge device with excellent durability, reliability and maintainability, and a superconducting device using the device.

Background art

In order to maintain a superconducting state, a superconducting device such as a superconducting motor needs to supply a cryogenic fluid such as liquid nitrogen or liquid helium to a place where superconducting is required. In particular, in a superconducting motor, it is necessary to efficiently supply and discharge a cryogenic fluid to a place where superconductivity is required, and the flow path to the superconducting part is a problem.

FIG. 8 of Japanese Patent Application Laid-Open No. 2004-235625 conceptually shows an apparatus for supplying and discharging a cryogenic fluid for supplying a cryogenic fluid to a rotor portion of a superconducting motor. In the superconducting motor described in Patent Document 1, the rotor assembly has a single disk-like rotor, and the configuration of the cryogenic fluid supply / discharge device for supplying the cryogenic fluid around it is simple. It is.

[0004] However, in the superconducting motor described in Japanese Patent Application Laid-Open No. 2004-235625, the rotor rotor rotates while immersed in a cryogenic fluid, so that power loss is large and practical application is difficult. . Further, in order to increase the output of the motor, it is necessary to use a plurality of disk-shaped rotors along the axial direction. In that case, for each outer periphery of each rotor, as shown in Japanese Patent Laid-Open No. 2004-235625 If the cryogenic fluid supply / discharge device of the configuration is installed, the entire superconducting motor device becomes large.

[0005] FIG. 9 of Japanese Patent Application Laid-Open No. 2003-65477 discloses that a cryogenic fluid is used as a rotor of a superconducting motor. As a cryogenic fluid supply / discharge device for supplying to the assembly, a double pipe structure is used. One of the double pipes is used as a cryogenic fluid inflow passage and the other as an outflow passage. In the superconducting motor described in Japanese Patent Laid-Open No. 2003-65477, there is a single flow path to which the cryogenic fluid is supplied, and there is a structure in which a plurality of positions are simultaneously cooled by a plurality of flow paths. is not.

In addition, in the invention described in Japanese Patent Application Laid-Open No. 2003-65477, as shown in FIG. 1, the vacuum cavity is used to insulate the entire outer periphery of the mouth assembly (see FIG. 16 in Patent Document 2). ). Therefore, if an attempt is made to cool a plurality of rotors of a superconducting device using the device disclosed in Japanese Patent Laid-Open No. 2003-65477, the vacuum cavity increases and the entire device increases.

[0007] Further, as shown in FIG. 7 of Japanese Patent No. 2838013, there is also known a cryogenic fluid supply / discharge device that attempts to circulate a refrigerant through a shaft hole formed in a rotating shaft of a rotor rear assembly. Yes. However, even in the cryogenic fluid supply / discharge device shown in Patent Document 3, there is a single flow path to which the cryogenic fluid is supplied, and a structure in which a plurality of flow paths are used to simultaneously cool a plurality of locations. It ’s a good idea.

[0008] In order to simultaneously cool a plurality of locations in a plurality of flow paths, it is necessary to provide a large number of seal locations. Therefore, if the seal is inappropriate, the cryogenic fluid may leak out of the device. In addition, when a large number of seal locations are provided, the number of locations that slide directly with the rotating shaft increases, and torcross tends to occur.

[0009] As shown in Japanese Patent Application Laid-Open No. 2004-19912, a rotary joint used in a polishing apparatus or the like for polishing the surface of a semiconductor wafer is known.

[0010] However, this conventional rotary joint is not premised on supplying a cryogenic fluid, and has a power that is not considered in the heat insulation. In particular, it was necessary to consider the flow path for vacuum insulation. If the heat insulation is insufficient, the cryogenic fluid will volatilize and dry sliding will occur at the sliding part, and the seal and the mating sliding part will soon wear out. In order to avoid such inconvenience, if it is attempted to insulate the entire apparatus by vacuum insulation, the apparatus for vacuum insulation becomes too large to be realistic. In addition, covering each flow path through which the cryogenic fluid circulates with a vacuum insulation space In addition, a flow path for evacuation is required, which is not realistic.

[0011] Therefore, while it is possible to supply cryogenic fluid to a plurality of rotating parts through different flow paths, vacuum insulation is efficiently performed at the minimum necessary part to warm the cryogenic fluid. Gasification is prevented, the leakage force is minimized, the leakage of cryogenic fluid to the outside is minimized, the power loss force S is extremely small and compact, and the force is also durable, reliable and easy to maintain, and low cost There was a need for a cryogenic fluid supply and discharge device.

Patent Document 1: Japanese Patent Laid-Open No. 2004-235625 (FIG. 8)

Patent Document 2: Japanese Patent Laid-Open No. 2003-65477 (Fig. 9)

Patent Document 3: Japanese Patent No. 2838013

Patent Document 4: Japanese Unexamined Patent Application Publication No. 2004-19912

Disclosure of the invention

Problems to be solved by the invention

[0012] The present invention has been made in view of such a situation, and an object thereof is to be a compact in which the heat loss is excellent, the leakage of the cryogenic fluid to the outside is minimized, the power loss is extremely small, and the force is also small. It is to provide a low-cost cryogenic fluid supply / discharge device excellent in durability, reliability and maintainability, and a superconducting device using the device.

Means for solving the problem

In order to achieve the above object, a cryogenic fluid supply / discharge device according to the first aspect of the present invention comprises:

A cryogenic fluid supply / discharge device for supplying and discharging a cryogenic fluid such as liquid nitrogen and liquid helium to a plurality of cooling-necessary locations in a rotor assembly, wherein a rotary fluid is provided at a shaft end of a rotating shaft of the rotor assembly. A joint is connected, and the rotary joint is

A rotary joint shaft that is detachably connected to the rotary shaft of the rotor assembly; and a casing that is disposed so as to cover the rotary joint shaft and is stationary with respect to the rotation of the rotary joint shaft; Have

Along the axial direction of the rotary joint shaft at different positions along the circumferential direction of the rotary joint shaft so as to communicate with a plurality of cooling-required portions in the rotor assembly, A plurality of joint-side flow paths are formed on the rotary joint shaft,

A rotation communication hole is formed on the outer periphery of the rotary joint shaft so as to communicate with the joint-side flow path at positions of different axial lengths along the axial direction of the respective joint-side flow paths. And

Among the rotation communication holes formed at different positions in the axial direction, a rotation ring is fixed to the outer periphery of the rotary joint shaft at every other rotation communication hole position in the axial direction. A rotation ring hole communicating with the rotation communication hole formed in a portion where the rotation ring is located,

In the casing, fixed connection ports communicating with the rotary communication holes or the rotary ring holes are formed at a plurality of axial positions corresponding to the rotary communication holes and the rotary ring holes, respectively.

A seal member that slides against the axial surface of the rotary ring and seals between the rotary communication holes adjacent to each other in the axial direction is provided inside the casing, and the center of the rotary joint shaft Is formed with an axial hole for vacuuming that communicates with the vacuum insulation space of the rotor assembly along the axial direction.

In the casing, a vacuum fixed connection port communicating with the vacuum drawing shaft hole is formed in a portion located on the axially outer side of the plurality of fixed connection ports,

Of the rotary joint shaft and the rotary ring, at least a portion that contacts the cryogenic fluid is made of a member having better heat insulation than metal,

A part of the casing in which the fixed connection port for vacuum and the fixed connection port are formed, and at least a portion in contact with the cryogenic fluid is made of a member having better heat insulation than metal. Features.

In the present invention, the rotating ring is fixed to the outer periphery of the rotary joint shaft at the position of every other rotational communication hole in the axial direction, and the seal member force slides with respect to the axial surface of the rotating ring. The gap between the cryogenic fluid flow paths adjacent to each other in the axial direction is sealed within one single. For this reason, the number of sealing members is reduced through the part where cryogenic fluid flows from the fixed connection port formed in the stationary member to the rotating communication hole or rotating ring hole, which is the rotating part. In addition, the cryogenic fluid can be efficiently sealed.

[0015] In the present invention, a vacuum suction shaft hole communicating with the vacuum heat insulating space of the rotor assembly is formed along the axial direction at the center of the rotary joint shaft, and a plurality of fixed holes are fixed to the casing. A fixed connection port for vacuum communicating with the evacuation shaft hole is formed in a portion located on the outer side in the axial direction of the connection port (the farthest side of the connection partial force with the rotor assembly). For this reason, the vacuum insulation space is formed on the side farthest from the connection part force with the rotor assembly, reaches the vacuum insulation space of the rotor assembly through the evacuation shaft hole, and the hollow portion of the rotor assembly is connected to the vacuum insulation space. Can be.

[0016] Therefore, the flow path of the cryogenic fluid from the plurality of fixed connection ports formed in the casing through the rotation communication hole or the rotation ring hole of the rotary joint shaft to the joint side flow path in the rotary joint shaft is It is efficiently insulated by the vacuum heat insulation space formed on the outer side in the axial direction of the rotary joint shaft and the member having better heat insulation than metal. In addition, since the hollow portion of the rotary shaft of the rotor assembly in the superconducting device is in communication with the evacuation shaft hole of the rotary joint shaft, the hollow portion also becomes a vacuum heat insulating space, and the tube disposed inside the hollow portion is a vacuum insulation space. Thermal insulation is improved. A cryogenic fluid circulates inside the tube.

[0017] These tubes communicate with a plurality of positions where cooling in the rotor assembly is necessary, and can cool each part individually.

[0018] In the present invention, at least a portion of the rotary joint shaft and the rotary ring that is in contact with the cryogenic fluid is formed of a member that has better heat insulation than metal, and a fixed connection port for vacuum. A part of the casing in which the fixed connection port is formed and at least a part in contact with the cryogenic fluid is formed of a member having better heat insulation than metal. For this reason, in the portion where the cryogenic fluid circulates inside the rotary joint, the portion in contact with the metal is reduced as much as possible, and the heat insulation is also improved in this respect.

[0019] Therefore, in the present invention, the cryogenic fluid is heated and gas is heated at all points from the stationary part of the rotary joint to the rotating part and the part requiring cooling in the rotor assembly part of the rotating partial force superconducting device. Can be minimized.

[0020] Further, in the present invention, in the casing of the rotary joint, the inlet of the cryogenic fluid and A fixed connection port is formed adjacent to the axial direction, and a cryogenic fluid flow path extending from the stationary member to the rotating member is formed adjacent to the axial direction. A space is formed. For this reason, the seal location for preventing leakage of cryogenic fluid to the outside of the casing inside the casing is one of the axially inner sides of the rotary joint shaft (the side close to the connecting portion with the rotary shaft of the rotor assembly). It becomes a power station and the leakage of cryogenic fluid to the outside can be minimized.

[0021] In the present invention, the fixed connection port serving as the inlet for the cryogenic fluid is formed adjacent to the axial direction, and the flow path of the cryogenic fluid from the stationary member to the rotating member is in the axial direction. Since they are formed adjacent to each other, they can cool each other and block the heat input path from the outside.

[0022] Further, the rotary joint is compact, and the heat transfer area with the outside can be minimized. Further, in the present invention, the cryogenic fluid can be introduced into the hollow portion of the rotor assembly from the rotary joint without using the vacuum heat insulating flexible tube.

[0023] Therefore, according to the present invention, it is possible to realize a compact cryogenic fluid supply / discharge device that has a very small power loss, is compact, has excellent durability, reliability, and maintainability, and is low in cost. it can.

[0024] Preferably, the rotary joint shaft is formed with a vacuum evacuating shaft hole therethrough, and the periphery of the axially outer end portion of the rotary joint shaft communicates with the vacuum fixed connection port. The shaft end is a vacuum chamber. By comprising in this way, the vacuum heat insulation effect improves. In addition, since the entire axially outer end of the rotary joint shaft is thermally insulated by vacuum, the cover member on the axially outer end side of the rotary joint shaft in the casing does not necessarily need to be composed of a heat insulating member. You may comprise with a metal member.

[0025] Preferably, the shaft end vacuum chamber is provided with a bearing for rotatably holding the rotary joint shaft with respect to the inside of the casing. Space can be used effectively by placing bearings in the shaft end vacuum chamber. In the present invention, the body of the casing on which the bearing outer ring in the bearing is mounted may be made of metal so that the outer periphery is warmed so that the bearing does not freeze.

[0026] Preferably, out of the fixed connection ports formed in the casing, the superconducting device Fixed connection port located at a close position Return port for cryogenic fluid. With this configuration, it is possible to block the heat input path from the outside to the flow path for supplying the cryogenic fluid.

[0027] Preferably, in the casing, a drain fixed connection port is formed at a position closer to the superconducting device than the fixed connection port corresponding to the return port. With this configuration, leakage of the cryogenic fluid to the outside of the casing can be prevented as much as possible, and the heat input path with external force can be blocked.

[0028] Preferably, the member strength fiber-reinforced plastic (FRP) is excellent in heat insulation. By comprising FRP, the heat insulation is improved as compared with metal, and the mechanical strength is sufficient, which is particularly preferable.

[0029] Preferably, the sealing member force is a bellows seal. The bellows seal is preferably a metal bellows seal consisting of a metal bellows and a sliding part. Furthermore, this metal bellows is a metal bellows using a nickel-base alloy such as Inconel 718, which has excellent low temperature brittleness. More preferably, it is rose. Metal bellows seals are often used as seals for cryogenic fluids, and the amount of leakage is small.

[0030] The stationary bellows seal forms a mechanical seal together with the rotating ring, and the rotary shaft diameter of the rotary joint can be set to the minimum diameter that can secure the required flow path. Can be determined and is not governed by the diameter of the rotating shaft in the superconducting device.

[0031] In addition, it is composed of a bellows seal that uses a short bellows in the axial direction, and the metal bellows seal slides on both sides of a single rotating ring, thereby reducing the axial length of the rotary joint. can do.

[0032] Furthermore, by forming a rotating ring hole on the outer peripheral surface of the rotating ring and forming a flow path for the cryogenic fluid, the overall width dimension of the rotating ring can be shortened.

[0033] Preferably, the sliding portion of the bellows seal is equipped with a fluorine resin member that slides with respect to the axial surface of the rotating ring. The bellows is placed on the stationary side, elastically biased in the axial direction by the bellows, and the sliding part is in close contact with the sliding surface of the rotating ring attached to the outer periphery of the rotary shaft. I do. Fluororesin is particularly preferred because of its excellent heat insulation, cold resistance and durability. [0034] Preferably, a sleeve made of a member having better heat insulation than metal is attached to the outer periphery of the rotary joint shaft, and the rotary ring is positioned by the sleeve so that the rotary joint is positioned. Fixed to the outer periphery of the shaft. The rotating ring that forms part of the mechanical seal is inserted into the rotary joint shaft in sequence using a sleeve made of heat insulating material such as FRP, and the sleeve collar is bolted or screwed from the shaft end. Tighten them together to prevent rotation. The use of the sleeve facilitates the mounting and positioning of the rotating ring. In addition, if the sleeve is made of a resin having excellent heat insulation, the heat insulation of the portion that comes into contact with the cryogenic fluid is improved.

[0035] Preferably, the casing is partitioned by the seal member so as to communicate with a fixed connection port formed in the casing and a rotation communication hole formed in the rotary joint shaft. The cryogenic fluid is introduced into each fixed connection port so that the pressure in each inflow space for the cryogenic fluid formed is substantially the same pressure. By configuring in this way, there is no differential pressure between the inflow spaces, and there is no leakage between them.

In order to achieve the above object, the cryogenic fluid supply / discharge device according to the second aspect of the present invention comprises:

A cryogenic fluid supply and discharge device that supplies and discharges cryogenic fluid such as liquid nitrogen and liquid helium to and from the places where cooling is required in the rotor assembly.

A rotary joint is connected to the shaft end of the rotary shaft of the rotor assembly, and the rotary joint includes a rotary joint shaft that is detachably connected to the rotary shaft.

And a casing that is arranged so as to cover the outer periphery of the rotary joint shaft and is stationary with respect to the rotation of the rotary joint shaft,

The rotary joint shaft includes a plurality of joint-side passages formed along the axial direction of the rotary joint shaft so as to communicate with the portion requiring cooling, and the rotary joint so as to communicate with the joint-side passage. A plurality of rotation communication holes formed on the outer periphery of the shaft, a communication hole for evacuation formed along the axial direction of the rotary joint shaft so as to communicate with the vacuum heat insulation space of the rotor assembly, and the vacuum suction A vacuum communication hole formed on the outer periphery of the rotary joint shaft so as to communicate with the communication hole,

The casing communicates with the rotation communication hole at a position corresponding to the rotation communication hole. A fixed connection port formed as described above, and a vacuum fixed connection port formed so as to communicate with the vacuum communication hole at a position corresponding to the vacuum communication hole.

A seal member for preventing leakage of the cryogenic fluid between the rotation communication hole and the fixed connection port is disposed.

[0037] In the cryogenic fluid supply / discharge device according to the second aspect of the present invention, the cryogenic fluid is supplied and discharged from the outer peripheral side force of the rotary joint shaft of the rotary joint. Parts such as a cooling fluid source are not arranged on the anti-load side of the joint, and motor loads such as propellers can be easily and continuously connected. Therefore, if the present invention is used, the entire apparatus can be made compact even if a plurality of motor loads are connected.

[0038] A superconducting device according to the present invention has the cryogenic fluid supply / discharge device described above.

[0039] Preferably, the rotary shaft of the rotor assembly is formed with a hollow portion as the vacuum heat insulating space,

In the hollow portion, there are a plurality of joint-side flow passages formed at different positions along the circumferential direction of the rotary joint shaft, and a plurality of tubes respectively communicating with the plurality of cooling-required portions in the rotor assembly. Arranged,

The hollow portion communicates with the surroundings of each cooling-required portion where the cryogenic fluid is introduced, and is maintained in an adiabatic vacuum state through the vacuum fixed connection port and the vacuuming shaft hole. With this configuration, it is possible to perform vacuum insulation at a minimum necessary portion in a plurality of cryogenic fluid supply channels, and to achieve both size reduction and vacuum insulation.

In the present invention, the superconducting device is not particularly limited, and examples thereof include a superconducting motor and a superconducting generator. Further, the superconducting motor is not limited to the axial gap type superconducting motor, and the present invention can also be applied to a radial gap type superconducting motor. In the axial gap type superconducting motor, the rotor of the rotating shaft is generally formed in a disk shape, and the stator is fixed to the casing through an axial gap between the rotor and the rotor. In addition, a radial gap type superconducting motor generally has a rotating shaft. A rotor is fixed to the outer periphery along the longitudinal direction, and a stator is fixed to the casing via a radial gap between the rotor and the rotor.

[0041] Preferably, the rotor assembly of the superconducting device is a rotor assembly of an axial gap type superconducting motor,

A plurality of disk-like rotors are fixed to the rotation shaft of the rotor assembly at predetermined intervals along the axial direction,

The cryogenic fluid flows through a tube disposed in the hollow portion of the rotor assembly so as to cool the coils of each disk-like rotor.

[0042] Preferably, stator cores fixed to a casing of the superconducting device are respectively arranged in front and rear positions in the axial direction of the respective disk-like rotors in the rotor assembly of the superconducting device.

[0043] Alternatively, the rotor assembly of the superconducting device is a rotor assembly of a radial gap type superconducting motor,

A rotor is fixed to the rotation shaft of the rotor assembly along the axial direction, and the stator is fitted with a predetermined radial gap in the radial direction perpendicular to the axial direction of the rotor. It may be fixed to the thing.

[0044] In that case, it is preferable that the cryogenic fluid flows through a tube disposed in a hollow portion of the rotor assembly so as to cool a coil constituting the rotor.

[0045] According to the present invention, it is excellent in heat insulation, minimizing leakage of cryogenic fluid to the outside, minimizing power loss, and having excellent durability, reliability, and maintainability. It is possible to provide a low-cost cryogenic fluid supply / discharge device and a superconducting device using the device.

Brief Description of Drawings

FIG. 1 is a schematic sectional view of a superconducting motor according to an embodiment of the present invention.

2 is a schematic sectional view of the rotary joint shown in FIG.

[FIG. 3] FIG. 3 is a view taken along the line III-III in FIG.

4 is an enlarged sectional view showing the relationship between the metal bellows seal shown in FIG. 2 and the flow path. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described based on embodiments shown in the drawings.

As shown in FIG. 1, a superconducting motor 2 according to an embodiment of the present invention is housed in an inner portion of a nosing / housing 4. A pair of bearings 6 are fixed to the housing 4, and these bearings 6 enable the rotary shaft 10 of the rotor assembly 20 in the motor 2 to rotate.

The rotor assembly 20 includes a rotating shaft 10 and four disk-shaped rotors 16 fixed at predetermined intervals along the axial direction of the rotating shaft 10. A stator 12 fixed to the casing 11 of the motor 2 is disposed at a predetermined axial gap at the front and rear positions of the disk-like rotor 16 in the axial direction. A magnet 14 is embedded in the stator 12, and a rotational force is applied to the rotor 16 between the stator 12 and a superconducting coil 15 disposed on the rotor 16. The casing 11 is fixed to the housing 4. As shown in FIG. 1, the superconducting motor 2 of this embodiment is an axial gap type superconducting motor.

The rotating shaft 10 is driven to rotate by the rotational force applied to the rotor 16, and the propeller 8 mounted on the outside of the housing 4 is rotated. The rotating shaft 10 of the rotor assembly 20 has a hollow portion (vacuum heat insulating space) 22 at the center of the shaft core.

[0051] Inside the hollow part 22, a supply tube 24 and a discharge tube 26 are arranged. Each supply tube 24 communicates with an internal cooling space (a place where cooling is necessary) 25 of each disk-like rotor 16 mounted on the outer periphery of the rotating shaft 10 at predetermined intervals along the axial direction.

A heat insulating vacuum chamber (not shown) is formed around the internal cooling space 25 of each rotor 16, and each vacuum chamber communicates with the hollow portion 22 of the rotating shaft 10.

[0053] Superconducting coils 15 are arranged in the internal cooling spaces 25 of the respective rotors 16, and the superconducting state is exhibited by the cryogenic fluid supplied to the internal cooling spaces 25 through the supply tubes 24. It will be cooled down to a low temperature. The cryogenic fluid to be supplied is not particularly limited, and examples thereof include liquid nitrogen and liquid helium.

[0054] In the internal cooling space 25 of each rotor 16, a supply tube 24 and a discharge tube 26 are provided. The cryogenic fluid that is connected and supplied to the internal cooling space 25 is discharged through each discharge tube 26.

[0055] The rotating shaft 10 in the superconducting motor 2 is connected to a motor load such as a propeller at one end on the drive side, and a rotary joint 30 constituting a cryogenic fluid supply / discharge device is connected to the other end on the non-drive side. Is done.

As shown in FIG. 2, the rotary joint 30 includes a rotary handle shaft 32 and a joint housing 38 that rotatably holds the rotary handle shaft 32 via a bearing 74. At one end of the rotary joint shaft 32 in the axial direction (connection side with the motor rotary shaft 10), a flange 34 is formed in a body.

[0057] The flange 34 is hermetically connected to one end of the rotating shaft 10 on the side opposite to the driving side with a bolt, a gasket, or the like. In order to hermetically connect the flange 34 to one end of the rotating shaft 10 on the non-driving side, a cold-resistant packing is attached to the joint surface between the flange 34 and one end of the rotating shaft 10 on the non-driving side. The cold-resistant packing is not particularly limited, and examples thereof include a fluorine resin packing such as PTFE, a metal packing made of a metal such as aluminum or stainless steel, or a composite packing combining these. The

A vacuum pulling shaft hole 36 penetrating along the axial direction is formed in the center of the shaft center of the rotary joint shaft 32, and the shaft hole 36 is a hollow portion 22 at the center of the flange 34. It communicates with.

[0059] As shown in Figs. 2 and 3, the rotary joint shaft 32 includes a shaft of the rotary joint shaft 32 at different positions along the circumferential direction of the rotary joint shaft 32 at the axially inner end. A plurality of joint-side flow paths 64 are formed along the direction. In the illustrated example, five joint-side flow paths 64 are formed at equal intervals in the circumferential direction, and the flow path lengths in the axial direction are different from each other.

[0060] A single discharge tube 26 is connected to the axially inner opening end 64a of the joint-side flow path 64 having the shortest flow path length. The single discharge tube 26 is connected to the four discharge tubes 26 shown in FIG. 1 inside the hollow portion 22 of the rotating shaft 10. The four supply tubes 24 shown in FIG. 1 are connected to the open ends 64a of the remaining four joint-side flow paths 64 shown in FIG.

[0061] The axial lengths of the joint-side flow paths 64 formed inside the rotary joint shaft 32 are different at predetermined intervals, and are different from each other in the axial direction of each flow path 64 (the anti-joint of the rotary joint shaft 32). Side) end Rotational communication holes 66 that open to the outer periphery of the rotary joint shaft 32 are connected in the vicinity.

[0062] On the outer periphery of the rotary joint shaft 32, a rotary ring 60 is air-tightly mounted at a position corresponding to the rotary communication hole 66 arranged on the innermost side in the axial direction. The rotating ring 60 is airtightly attached at the position of the rotation connecting hole 66. Between the axial directions of the rotary ring 60, an intermediate sleeve 70 is mounted on the outer periphery of the rotary joint shaft 32, and an end sleeve 72 is bolted or screwed on the outer periphery of the outer end of the rotary joint shaft 32 in the axial direction. The rotating ring 60 and the intermediate sleeve 70 are collectively stopped. That is, the rotary ring 60 is fixed to the outer periphery of the rotary joint shaft 32 and is rotated together.

[0063] On the outer periphery of the rotating ring 60, a rotating ring hole 62 communicating with a rotating communication hole 66 formed in a portion where the rotating ring 60 is located is formed. As shown in FIG. 4, the intermediate sleeve 70 has a rotary communication hole 6 formed in a portion where the intermediate sleeve 70 is located.

A communication hole 71 communicating with 6 is formed.

As shown in FIG. 2, the casing 38 is a bearing located on the outer side in the axial direction of the rotary joint shaft 32.

An end cover 40 in which 74 is mounted is provided, and a bearing retaining ring 46 in which a bearing 74 on the inner side in the axial direction of the rotary joint shaft 32 is mounted.

[0065] Between the end cover 40 and the bearing retaining ring 46, the connection port forming rings 42a to 42g and the bellows retaining ring 44 are alternately and airtightly connected, and the whole constitutes the casing 38. Yes.

[0066] A single or a plurality of vacuum fixed connection ports 50 are formed in the connection port forming ring 42a located on the outermost side in the axial direction of the rotary joint shaft 32. The connection port 50 communicates with a shaft end vacuum chamber 90 formed in a gap between the outer periphery of the rotary joint shaft 32 in the axial direction and the end cover 40 inside the casing 38. A vacuum evacuation device is connected to the connection port 50, and the shaft end vacuum chamber 90 and the hollow portion 22 are depressurized through the connection port 50 to maintain a high vacuum state. The shaft end vacuum chamber 90 communicates with a vacuum pulling shaft hole 36 formed in the rotary joint shaft 32. The evacuation shaft hole 36 communicates with the connection port 50 through a vacuum communication hole 91 formed radially in the vicinity of the axially outer end of the rotary joint shaft 32. [0067] On the axially inner side of the connection port forming ring 42a in which the vacuum fixed connection port 50 is formed, there is a supply fixed connection port 52 for supplying a cryogenic fluid via the bellows holding ring 44. Four connection port forming rings 42b to 42e each formed are arranged. Cryogenic fluid such as liquid-nitrogen or liquid-helium at the same temperature is supplied from the connection ports 52 formed in the four connection-port-forming rings 42b to 42e at the same pressure. It is.

Note that it is preferable that the pressure forces of the cryogenic fluid supplied from the four connection ports 52 be almost the same in order to improve the sealing performance in the bellows seal 80 described later.

[0068] The cryogenic fluid supplied from each connection port 52 is supplied to the internal cooling space 25 of the disk-like rotor 16 via the supply tube 24 shown in FIG.

[0069] Of the connection ports 52 formed in each of the connection port forming rings 42b to 42e, the connection port 52 positioned on the outermost side in the axial direction is formed on the rotary ring 60 positioned on the outermost side in the axial direction. The rotary ring 60 is formed at a position communicating with the rotary ring hole 62. The sliding part of the tip of the metal bellows seal 80 rotates and slides on both sides in the axial direction of the rotating ring 60 to seal the space flow path 92 between the rotating ring hole 62 and the connection port 52. It has become.

[0070] Each metal bellows seal 80 is composed of a metal bellows and a tip sliding portion, and the base end portion of the metal bellows is fixed to the inside of the bellows holding ring 44 and can be expanded and contracted in the axial direction. The panel is urged so that the tip sliding portion is pressed against each side of the rotating ring 60. The tip sliding portion of the bellows seal 80 is made of, for example, fluorine resin such as PTFE or carbon. Fluorine resin is excellent in abrasion resistance, strength and cold resistance.

[0071] The metal bellows is preferably a metal bellows using a nickel alloy such as Inconel 718 having excellent low-temperature brittleness. Metal bellows seals are suitable for cryogenic fluids.

The metal bellows seal 80 located on the outermost side in the axial direction seals between the shaft end vacuum chamber 90 and the space flow path 92. The metal bellows seal 80 located next to it is a cryogenic fluid. The space channel 92 to which the gas is supplied and the space channel 94 adjacent thereto are sealed.

As shown in FIG. 2, the supply connection port 52 located between the rotating ring 60 and the rotating ring 60 along the axial direction is a spatial flow located between the rotating ring 60 and the rotating ring 60. It is designed to communicate with Road 94. The space flow path 94 is sealed with a metal bellows seal 80 so as not to communicate with the rotary ring hole 62 of the rotary ring 60. The space channel 94 communicates with the rotary communication hole 66 through a communication hole 71 formed in the intermediate sleeve 70.

[0074] On the inner side in the axial direction of the four connection port forming rings 42b to 42e, a return fixed connection port 54 for discharging used cryogenic fluid is formed through a bellows holding ring 44. A connection port forming ring 42f is arranged. The return fixed connection port 54 communicates with the rotation ring hole 62 of the rotation ring 60 through the space flow path 92, and communicates with the discharge tube 26 through the rotation communication hole 66 and the shortest joint side flow path 64. .

[0075] Of all the connection port forming rings 42a to 42g, a drain fixed connection port 56 is formed in the connection port forming ring 42g located on the innermost side in the axial direction. The drain fixed connection port 56 communicates with the outer periphery of the rotary joint shaft 32 positioned on the innermost side in the axial direction outside the flange 34 and the bearing 74! /.

[0076] In the present embodiment, the rotary joint shaft 32, the sleeves 70 and 72, and the rotary ring 60 are made of FRP. Of the members that make up the casing 38, the connection port forming rings 42a to 42g are made of FRP. The end cover 40, the bearing retaining ring 46, and the bellows retaining ring 44 are made of stainless steel, Inconel, titanium, etc. Made of metal. The outer periphery of the holding rings 44 and 46 can be made of FRP.

[0077] The bearing 74 positioned at the outer end of the rotary joint shaft 32 in the axial direction is preferably disposed within the end vacuum chamber 90 and configured by a sealed bearing filled with vacuum grease. Yes. The bearing 74 on the inner side in the axial direction of the rotary joint shaft 32 is preferably installed at a position as far as possible in the radial direction from the joint-side flow path 64 of the cryogenic fluid provided in the rotary joint shaft 32. That is, it is preferable that the outer diameter of the rotary joint shaft 32 held by the bearing 74 on the side close to the flange 34 is formed to be larger than the other portions. The bearing 74 on the side close to the flange 34 is in contact with the outside air and operates in an air atmosphere.

[0078] Each of these bearings 74 is disposed inside the housing 38, respectively. The flow path (52, 92, 94, 62, 66, 64) through which the cryogenic fluid circulates is installed at both ends, and is insulated by the FRP sleeve 72 and the rotary joint shaft 32 with excellent heat insulation. It is. Since each bearing 74 is held inside the metal end cover 40 and the bearing retaining ring 46, the bearing 74 is heated from the outside of the end cover 40 or the bearing retaining ring 46 to prevent the bearing from freezing. Freezing may be prevented.

[0079] According to the rotary joint 30 and the superconducting motor 2 using the rotary joint 30 according to the present embodiment, the rotary ring 60 is provided on the outer periphery of the rotary joint shaft 32 at the positions of the other rotational communication holes 66 in the axial direction. Is fixed, metal bellows seal 80 force slides on both axial sides of the rotating ring 60, and seals between the spatial flow paths 92 and 94 that are axially adjacent to each other in the casing 38. is doing. For this reason, the number of seal members in the portion where the cryogenic fluid flows from the fixed supply port 52 for supply formed in the casing 38 as a stationary member to the rotary communication hole 62 or the rotary ring hole 66 as the rotating portion. And the cryogenic fluid can be efficiently sealed.

In the present embodiment, the evacuation shaft hole 36 communicating with the hollow portion 22 of the rotary shaft 10 is formed in the center of the rotary joint shaft 32 along the axial direction. A vacuum fixed connection port 50 communicating with the vacuum suction shaft hole 36 is formed in a portion located on the outer side in the axial direction (the farthest side of the connection partial force with the rotor assembly). For this reason, it is possible to form a connection portion force with the vacuum adiabatic space force rotor assembly 20 at the farthest shaft end portion, and also to make the hollow portion 22 of the rotary shaft 10 a vacuum insulation space.

Therefore, the poles that pass from the plurality of fixed connection ports 52 formed in the casing 38 to the joint-side flow path 64 in the rotary joint shaft 32 through the rotary communication hole 66 or the rotary ring hole 62 of the rotary joint shaft 32. The flow path of the low-temperature fluid is efficiently insulated by the vacuum heat insulating space of the shaft end vacuum chamber 90 formed on the outer side in the axial direction of the rotary joint shaft 32 and the heat insulating member made of FRP. Further, since the hollow portion 22 of the rotary shaft 10 in the superconducting motor 2 communicates with the vacuum pulling shaft hole 36 of the rotary joint shaft 32, the hollow portion 22 also becomes a vacuum heat insulating space and is disposed in the interior thereof. The heat insulation of some tubes 24 and 26 is improved. A cryogenic fluid circulates inside the tubes 24 and 26.

[0082] These tubes 24 and 26 are cooled in the rotor assembly 20 as shown in FIG. Are connected to the internal cooling space 25 at multiple positions where it is necessary to cool each part individually.

In the present embodiment, at least a portion of the rotary joint shaft 32 and the rotary ring 60 that is in contact with the cryogenic fluid is formed of an FRP member that has better heat insulation than metal. The casing 38 includes a metal end cover 40 and rings 44 and 46, and FRP connection port forming rings 42a to 42g. For this reason, at least the part in contact with the cryogenic fluid can be composed of an FRP member having better heat insulation than metal, and the part in contact with the metal in the part where the cryogenic fluid circulates inside the rotary joint 30. The heat insulation is improved in this respect as well.

Therefore, in this embodiment, the cryogenic temperature is reduced at all points from the stationary part of the rotary joint 30 to the rotating part and the internal cooling space 25 of the rotating part force 20 of the rotor assembly 20 of the superconducting motor 2. It is possible to minimize the fluid (liquid) from warming and gasifying. In the conventional apparatus, a gas such as helium gas has been mainstream, but in the present invention, a liquid such as liquid nitrogen can be used. In addition, since high heat insulation can be realized, it is possible to suppress frost formation on the rotary joint 30 and the rotor assembly 20.

In this embodiment, since the cryogenic fluid can be supplied to a plurality of internal cooling spaces (locations requiring cooling) 25 using a single rotary joint 30 in this embodiment, the apparatus can be reduced in size. be able to. In addition, since the flow paths from the rotary joint 30 to the plurality of internal cooling spaces 25 are independent, the reliability is high. Therefore, it is possible to supply a low-temperature fluid to the internal cooling space 25 farthest from the rotary joint 30 as much as the internal cooling space 25 located closest.

[0086] In the present embodiment, in the casing 38 of the rotary joint 30, the fixed connection port 52 serving as the inlet of the cryogenic fluid is formed adjacent to the axial direction, and the stationary member is rotated to the rotating member. A cryogenic fluid flow path is formed adjacent to each other in the axial direction, and a shaft end vacuum space 90 is formed on the outer side in the axial direction. For this reason, inside the casing 38, the seal portion for preventing leakage of cryogenic fluid to the outside of the casing is located on the inner side in the axial direction of the rotary joint shaft 32 (close to the connecting portion with the rotary shaft of the rotor assembly). ) Thus, leakage of the cryogenic fluid to the outside can be minimized. In addition, since the seal diameter can be reduced, the structure is difficult to leak.

[0087] In the present embodiment, the fixed connection port 52 serving as an inlet for the cryogenic fluid is formed adjacent to the axial direction, and the flow path of the cryogenic fluid from the stationary member to the rotating member is the axial direction. Therefore, in these channels, the heat input path of external force that hardly transfers heat to each other can be blocked.

Further, in the present embodiment, among the fixed connection ports formed in the casing 38, the fixed connection port arranged at a position close to the rotating shaft 10 of the superconducting motor 2 54 force Cryogenic fluid return port It is. With this configuration, the heat input path from the outside to the flow path for supplying the cryogenic fluid can be blocked.

Furthermore, in the present embodiment, a drain fixed connection port 56 is formed at a position closer to the rotary shaft 10 than the fixed connection port 54 corresponding to the return port. With this configuration, leakage of the cryogenic fluid to the outside of the casing 38 can be prevented as much as possible, and the heat input path from the outside can be blocked.

[0090] In this embodiment, since the pressure of the cryogenic fluid flowing into each of the spatial channels 92 and 94 is substantially the same, the pressure between these channels 92 and 94 is There is no differential pressure and there is no leakage between each other.

In this embodiment, the stationary metal bellows seal 80 forms a mechanical seal together with the rotary ring 60, and the rotary shaft diameter of the rotary joint shaft 32 is the smallest diameter that can secure a necessary flow path. The size in the radial direction can be arbitrarily determined and is not governed by the shaft diameter of the rotating shaft 10 in the superconducting motor.

[0092] Further, it is constituted by a bellows seal 80 using a short bellows in the axial direction, and the metal bellows seal 80 slides on both side surfaces of one rotating ring 60, so that the axial direction of the rotary joint 30 The length can be made compact. Furthermore, the metal bellows seal 80 follows the sliding surface of the rotating ring 60 due to the expansion of the bellows, and has no friction part other than the sliding surface, so the load due to the bellows must be minimized. Can do. For this reason, there is extremely little torque cross due to the seal.

[0093] Among the metal bellows seals to be mounted, the seal differential pressure acts on the case. There are only two force points inside the shaft 38 at both ends in the axial direction. The other seals contain a cryogenic fluid of approximately the same pressure on both the inner and outer circumferences of the seal, and there is no differential pressure, so the pressing force on the sliding surface is only an elastic bias by a metal bellows. It is. For this reason, the temperature rise of the cryogenic fluid due to friction is extremely low.

[0094] Furthermore, by forming the rotating ring hole 62 in the rotating ring 60 and forming the flow path for the cryogenic fluid, the overall width dimension of the rotating ring 60 can be shortened. Furthermore, the rotary joint 30 is compact, and the heat transfer area with the outside can be minimized.

In this embodiment, the hollow portion 22 formed in the rotating shaft 10 of the superconducting motor 2 communicates with the periphery of each internal cooling space 25 into which the cryogenic fluid is introduced, and is fixed for vacuum. It is maintained in an adiabatic vacuum state through the connection port 50, the vacuuming shaft hole 36 and the hollow portion 22 of the rotary shaft 10. This configuration makes it possible to insulate the minimum necessary part of the vacuum, and to achieve compactness of the device while achieving vacuum insulation.

Furthermore, in the present embodiment, the rotating shaft 10 of the superconducting motor 2 does not need to be a good multi-pipe as long as it has a hollow portion 22 that can accommodate tubes 24, 26, etc. for fluid transfer. . In addition, since the hollow rotating shaft is vacuum insulated, it is not necessary to separately heat the rotating shaft 10. Furthermore, the rotary joint 30 can be easily attached and detached, and the manpower is not reduced.

[0097] In addition, the connection force from the superconducting motor 2 side to the cryogenic fluid supply Z discharge port of the rotary joint 30 is provided on the shaft end surface of the flange 34 of the rotary joint 30. The man-hour is not strong. In addition, the shape of the shaft end of the rotary shaft 10 is simple and the number of machining steps is extremely small! /.

Therefore, according to this embodiment, the heat dissipation is excellent, the leakage of the cryogenic fluid to the outside is minimized, the power loss is extremely small, and the force is durable, reliable, and maintainable. An excellent and low-cost cryogenic fluid supply / discharge device and a superconducting motor 2 using the device can be provided.

[0099] The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention.

[0100] For example, in the above-described embodiment, the force using a so-called axial gap type superconducting motor as the superconducting device is a so-called radial gap type superconducting motor. It can also be applied to data. Further, the present invention is not limited to a superconducting motor but can be applied to a superconducting device such as a superconducting generator.

[0101] In the above-described embodiment, in order to hold the metal bellows seal 80 on the inner side of the ring 44, a force composed of these rings 44 made of metal. If a cull seal can be used, these rings 44 can be made of a member having excellent heat insulation other than metal.

[0102] Furthermore, in the above-described embodiment, as shown in FIG. 1, the force provided by four rotors 16 along the axial direction of the rotary shaft 10 is not limited, and the number is not limited to four or more, or two or 3 is OK. It is also possible to arrange two or more supply tubes 26 for a single rotor 16.

[0103] Furthermore, in the above-described embodiment, the force for cooling only the inside of the rotor assembly 20 can be used to cool the outside of the rotor assembly 20 by using the apparatus according to the present invention.

[0104] In the above-described embodiment, the connection between the rotary shaft 10 of the rotor assembly 20 and the rotary joint 30 is a flange connection.

Claims

The scope of the claims

A cryogenic fluid supply / discharge device for supplying and discharging a cryogenic fluid such as liquid nitrogen or liquid helium to a plurality of cooling-necessary locations in a rotor assembly, wherein a rotary joint is attached to a shaft end of a rotating shaft of the rotor assembly. Is connected, and the rotary joint is

A plurality of joint-side flow paths along the axial direction of the rotary joint shaft at different positions along the circumferential direction of the rotary joint shaft so as to communicate with a plurality of cooling-needed portions in the rotor assembly. Is formed on the rotary joint shaft,

In the casing, a vacuum fixed connection port communicating with the vacuum drawing shaft hole is formed in a portion located on the axially outer side of the plurality of fixed connection ports, Of the rotary joint shaft and the rotary ring, at least a portion that contacts the cryogenic fluid is made of a member having better heat insulation than metal,

A part of the casing in which the fixed connection port for vacuum and the fixed connection port are formed, and at least a portion in contact with the cryogenic fluid is made of a member having better heat insulation than metal. Characterize

Cryogenic fluid supply / discharge device.

[2] The rotary joint shaft is formed with a shaft hole for evacuation penetrating, and the periphery of the axially outer end of the rotary joint shaft communicates with the fixed connection port for vacuum. 2. The cryogenic fluid supply / discharge device according to claim 1, wherein the device is a chamber.

3. The cryogenic fluid supply / discharge device according to claim 2, wherein a bearing that rotatably holds the rotary joint shaft with respect to the inner side of the casing is disposed in the shaft end vacuum chamber.

[4] The fixed connection port arranged at a position close to the superconducting device among the fixed connection ports formed in the casing is a return port for a cryogenic fluid. For cryogenic fluid supply and discharge.

[5] The cryogenic fluid supply / discharge according to claim 4, wherein in the casing, a drain fixed connection port is formed at a position closer to the superconducting device than the fixed connection port corresponding to the return port. Equipment.

6. The cryogenic fluid supply / discharge device according to any one of claims 1 to 5, wherein the member having excellent heat insulation is a fiber reinforced plastic.

7. The cryogenic fluid supply / discharge device according to any one of claims 1 to 6, wherein the seal member force is a bellows seal.

8. The cryogenic fluid supply / discharge device according to claim 7, wherein the sliding portion of the bellows seal is equipped with a fluorine resin member that slides with respect to the axial surface of the rotating ring.

[9] A sleeve made of a member having better heat insulation than metal is attached to the outer periphery of the rotary joint shaft, and the rotary ring is positioned by the sleeve so that the rotary joint shaft The cryogenic fluid supply / discharge device according to any one of claims 1 to 8, which is fixed to the outer periphery.

[10] A fixed connection port formed in the casing and a rotation formed in the rotary joint shaft. The poles are arranged so that the pressure in each inflow space for the cryogenic fluid that is partitioned by the seal member and formed inside the casing is substantially the same pressure so as to communicate with the rolling communication hole. The cryogenic fluid supply / discharge device according to any one of claims 1 to 9, wherein a cryogenic fluid is introduced from each of the fixed connection ports.

[11] A cryogenic fluid supply / discharge device that supplies and discharges cryogenic fluid such as liquid nitrogen and liquid helium to and from the cooling assembly in the rotor assembly.

A rotary joint is connected to the shaft end of the rotary shaft of the rotor assembly, and the rotary joint covers a rotary joint shaft that is detachably connected to the rotary shaft and an outer periphery of the rotary joint shaft. And a casing that is stationary with respect to the rotation of the rotary joint shaft,

The rotary joint shaft includes a plurality of joint-side passages formed along the axial direction of the rotary joint shaft so as to communicate with the portion requiring cooling, and the rotary joint so as to communicate with the joint-side passage. A plurality of rotation communication holes formed on the outer periphery of the shaft, a vacuum suction communication hole formed along the axial direction of the rotary joint shaft so as to communicate with the vacuum heat insulation space of the rotor assembly, and the vacuum A vacuum communication hole formed on the outer periphery of the rotary joint shaft so as to communicate with the pulling communication hole,

The casing communicates with the vacuum communication hole at a position corresponding to the rotation communication hole and a fixed connection port formed to communicate with the rotation communication hole at a position corresponding to the rotation communication hole. A fixed connection port for vacuum formed on

A cryogenic fluid supply / discharge device, wherein a sealing member for preventing leakage of the cryogenic fluid between the rotation communication hole and the fixed connection port is disposed.

[12] A superconducting device having the cryogenic fluid supply / discharge device according to any one of claims 1 to 11.