JPH08226443A - Superconductive magnetic bearing device - Google Patents

Abstract

PURPOSE: To provide a superconductive magnetic bearing device capable of coping with high speed rotation and supporting a heavy weight by improving the mechanical strength of an annular permanent magnet, particularly a large- sized annular permanent magnet. CONSTITUTION: In a superconductive magnetic bearing device 1 composed of a superconductor part 5 attached to one of a rotor part A and a stator part B and a magnet part 8 attached to the other, the magnet part is a integral annular magnet structure having a plurality of annular magnets manufactured by hot bending work and attached circumferentially adjacent to each other in combination, and further a reinforcing member 6 is disposed on the outer periphery of the magnet part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a superconductor used in, for example, a fluid machine or a machine tool that requires high-speed rotation, an electric power storage device for converting surplus electric power into kinetic energy of a flywheel, and storing the electric power. The present invention relates to a superconducting bearing device.

[0002]

2. Description of the Related Art In recent years, a superconducting magnetic bearing device has been developed which utilizes a superconductor to support a rotating body (rotating shaft) in a non-contact state so as to rotate at a high speed. The basic structure of a superconducting magnetic bearing device is, for example, Japanese Patent Laid-Open No. 5-1802.
As shown in 25, a rotating body in which an annular permanent magnet is embedded is generally fixed in space by a superconductor serving as a fixed portion and a pinning force, and rotates about a rotation axis. Further, the superconducting magnetic bearing device utilizing the pinning force of the superconductor and the permanent magnet also has a feature of generating a large loading force,
Taking advantage of these characteristics, it is considered that a heavy object such as a flywheel is rotated at high speed to store electric power as kinetic energy of the flywheel, which is applied to a power storage device having a large energy density. For the purpose of power storage,
The flywheel-mounted superconducting magnetic bearing device is, for example, when CFRP is used as a material in the concept design of the 8MWH class high temperature superconducting levitation flywheel power storage system of the 1992 National Conference of the Electrical Society of Japan, page 8-134. It is reported that the flywheel part has a diameter of 6.7 m and a weight of 103 tons. At that time, the permanent magnet used must be a large-diameter magnet having a diameter of at least several meters.
Due to the difficulty of manufacturing large permanent magnets, it was necessary to assemble the magnets in pieces and some examples were given.
(For example, Japanese Patent Laid-Open No. 6-2646) On the other hand, in a flywheel power storage device, a large load is applied to the superconducting magnetic bearing device in order to support a heavy flywheel. The loading force of a superconducting magnetic bearing device using a superconductor and a permanent magnet is proportional to the magnetic field gradient generated by the permanent magnet and the magnitude of the magnetization moment of the superconductor. Therefore, a proposal to increase the magnetic field gradient of the permanent magnet by utilizing the repulsion of the magnetic flux of the permanent magnet is disclosed in, for example, Japanese Patent Laid-Open No. Hei 6
-42532 was shown in FIG.

[0003]

However, the prior art described in the above publication has the following problems.

Needless to say, a large-diameter magnet is required for a superconducting magnetic bearing used in a flywheel power storage device, but in order to increase the energy density of the power storage device, high speed rotation is required. A large-diameter permanent magnet with high mechanical strength that withstands the above is required. That is, the flywheel main body can be rotated at high speed if a high-strength material such as CFRP is used,
In that case, the permanent magnet rotating with the flywheel is required to have the same mechanical strength as CFRP.
However, the mechanical strength of permanent magnet materials is generally very weak. For example, the tensile strength per unit square mm of a Nd-Fe-B system or Sm-Co system sintered magnet, which is a typical high-performance magnet, is about several kilograms, whereas the strength of a CFRP material is several hundred kilograms. There is a difference in mechanical strength between the two so that they cannot be compared. Therefore, even if a high-strength material is used as the flywheel material, the rotation speed must be kept low due to the strength limit of the permanent magnet unless the mechanical strength of the permanent magnet is increased. what if,
When a magnet cracks or the like during rotation, the dynamic balance of the rotating body is lost before the magnet portion scatters, resulting in an extremely dangerous state. In addition, JP-A-6-264
As shown in FIG. 6, when the divided magnets are combined in advance, a gap is generated between the divided magnets due to the rotation, and the dynamic balance as the rotating body is lost as described above, resulting in extremely unstable. When an adhesive is used for the magnets so that no gap is generated between the magnets, the adhesive strength is determined by the adhesive used. Generally, a resin-based adhesive is often used, and its adhesive strength is about several kg per unit square mm like the permanent magnet manufactured by the above-mentioned sintering method, which is more than that of a material such as CFRP. It will be more than 2 digits smaller. As described above, the rotational speed limit of the superconducting magnetic bearing device is determined by the strength limit of the permanent magnet.

On the other hand, as in the example shown in FIG. 32 of Japanese Patent Laid-Open No. 6-42532, in a magnetic circuit in which the magnetic field strength and the magnetic field gradient are increased in order to increase the loading force, the magnetizing direction of the magnet is in the radial direction. So-called radial magnetization, which is to magnetize, is required. However, it is generally known that it is difficult to obtain a large annular permanent magnet magnetized in the radial direction. It is a Nd-Fe-B produced by a sintering method,
An anisotropic magnet such as an Sm-Co system needs to be pressed in a magnetic field in order to give magnetic anisotropy. However, the pressing machine and the coil yoke for giving an orientation magnetic field are large in size due to their arrangement. It will be very difficult. Further, in order to give radial anisotropy to the arcuate or annular magnet, a point-oriented magnetic field is required, which further increases the difficulty. Also, in the magnetizing step, it is extremely difficult to magnetize an annular magnet having a diameter of 1 m or more, for example. Therefore, JP-A-6-4253
The magnetic circuit as shown in FIG. 32 of No. 2 is formed by finely processing an arc shape and then assembling magnetized magnet pieces into an annular shape. However, it is extremely difficult to arrange magnetized magnets closely because of the repulsive force of attraction between the magnets.
Even if a jig or the like is used for assembly, a gap or a step is generated between the magnets. In the superconducting magnetic bearing device, the mechanical accuracy of the permanent magnet causes vibration and loss of the bearing, making it impossible to rotate at high speed. Further, since the ring-shaped permanent magnet manufactured in this manner is not perfectly point-oriented, the surface magnetic flux density of the ring-shaped permanent magnet is greatly uneven, resulting in a large rotation loss.

Therefore, the purpose of the present invention is to realize a superconducting magnetic bearing device capable of stably rotating a large heavy object such as a flywheel at a high speed.

[0007]

In order to achieve the above object, a superconducting magnetic bearing device according to the first aspect of the present invention is mounted on one of a rotating body portion and a fixed body portion and on the other. And a magnet part, wherein the superconductor part is composed of a superconductor having a restoring force between the magnet part and the support part supporting the superconductor, and the magnet part is a rotor part. In a superconducting magnetic bearing device of a type configured to include an annular magnet whose axis is concentric, the magnet portion is a combination of a plurality of arc-shaped magnets manufactured by hot bending, and the circles adjacent to each other in the circumferential direction. The structure is such that an arcuate magnet is bonded to each other to form an integral annular magnet structure, and a reinforcing member is arranged on the outer circumference of the magnet portion.

A superconducting magnetic bearing device according to a second aspect of the present application comprises a superconductor portion mounted on one of a rotating body portion and a fixed body portion and a magnet portion mounted on the other, and the superconductor portion comprises: A superconductor having a restoring force between the magnet part,
In a superconducting magnetic bearing device of a type configured with a support body that supports this superconductor, and the magnet portion is provided with an annular magnet whose axis is concentric with the rotating body portion, the magnet portion is hot. Is formed by a plurality of arc-shaped magnets manufactured by bending at, and an annular member circumscribing the outer peripheral portion of the arc-shaped magnet, and the arc-shaped magnet is annularly arranged inside the annular member, It has an integral annular magnet structure in which a member and the annular magnet are bonded.

In the superconducting magnetic bearing device according to the third aspect of the present application, the coefficient of thermal expansion of the annular member is lower than the coefficient of thermal expansion of the arc-shaped magnet.

In the superconducting magnetic bearing device according to the fourth aspect of the present invention, the magnet portion is composed of a plurality of integral annular magnets having different diameters.
The plurality of integral annular magnets are formed by a multiplex structure in which the axis of the rotating body is concentric.

A superconducting magnetic bearing device according to a fifth aspect of the present invention comprises a superconducting portion mounted on one of the rotating body portion and the fixed body portion and a magnet portion mounted on the other, and the superconducting portion comprises: It is composed of a superconductor having a restoring force between the magnet part and a support body that supports the superconductor, and the magnet part is provided with an annular magnet having the axis of the rotor part as a concentric axis. In the superconducting magnetic bearing device of the type, the magnet portion is manufactured by hot bending, and a plurality of arc-shaped magnets having magnetic anisotropy in the radial direction are combined, and the arc-shaped magnets that are adjacent in the circumferential direction are combined. It is an integrated annular magnet structure in which the two are bonded to each other. As the integrated annular magnet, two or more integrated annular magnets of different diameters magnetized so that the same poles face each other in the radial direction are arranged and are adjacent in the radial direction. An annular member is provided between the annular magnets, It has a configuration which arranged reinforcing member on the outer periphery of Ishibe.

A superconducting magnetic bearing device according to a sixth aspect of the present invention comprises a superconductor portion mounted on one of the rotating body portion and the fixed body portion and a magnet portion mounted on the other, and the superconductor portion comprises: It is composed of a superconductor having a restoring force between the magnet part and a support body that supports the superconductor, and the magnet part is provided with an annular magnet having the axis of the rotor part as a concentric axis. In the superconducting magnetic bearing device of the type, the magnet portion is manufactured by hot bending, and a plurality of arc-shaped magnets having magnetic anisotropy in the radial direction are combined, and the arc-shaped magnets that are adjacent in the circumferential direction are combined. It is an integrated annular magnet structure in which the two are bonded to each other. As the integrated annular magnet, two or more integrated annular magnets of different diameters magnetized so that the same poles face each other in the radial direction are arranged and are adjacent in the radial direction. An annular member is provided between the annular magnets, Jo member forms a superposed structure radially double, has a configuration which arranged reinforcing member on the outer periphery of the magnet part.

A superconducting magnetic bearing device according to a seventh aspect of the present invention comprises a superconductor portion mounted on one of the rotating body portion and the fixed body portion and a magnet portion mounted on the other, and the superconductor portion comprises: A superconductor having a restoring force between the magnet portion and a support for supporting the superconductor, wherein the magnet portion is provided with an annular magnet concentric with the axis of the rotor portion, In a superconducting magnetic bearing device of a type in which the annular magnet and the superconductor portion are arranged to face each other with a gap in the radial direction of the rotating body portion, the magnet portion is manufactured by hot bending. A plurality of arc-shaped magnets are combined and the arc-shaped magnets adjacent to each other in the circumferential direction are bonded to each other to form an integrated annular magnet structure. The integrated annular magnet is magnetized so that the same poles face each other in the axial direction of the same diameter. At least two integrated rings A magnet disposed, it has a structure in which an annular member between the integral annular magnet axially adjacent.

In the superconducting magnetic bearing device according to the eighth aspect of the present invention, after the magnet portion forms the integral annular magnet structure,
It is magnetized.

In the superconducting magnetic bearing device according to the ninth aspect of the present application, the mechanical strength of the bonded portion between the arc-shaped magnets is the same as that of the arc-shaped magnet alone.

[0016]

【Example】

(Embodiment 1) FIG. 1 is a longitudinal sectional view showing a main part of a superconducting bearing device. The superconducting bearing device 1 is provided in a housing (not shown). That is, a cooling case 2 supported and fixed to the housing is provided inside the housing, and a disc-shaped support body 3 is fixed inside the cooling case 2. The support 3 is made of copper or another metal material, and the superconductor 4 is embedded in the support 3 in an annular shape. The support 3 and the superconductor 4 form a superconductor portion 5. There is. In this embodiment, the superconductor portion 5 is provided on the fixed body portion B, and the magnet portion 8 described later is provided on the rotating body portion A, respectively. The superconductor 4 is composed of a yttrium-based high-temperature superconductor, for example, a mixture of normal conductive particles Y ₂ Ba ₁ Cu ₁ uniformly in a substrate made of YBa ₂ Cu ₃ O _x , and an annular permanent magnet described later. 11 has the property of restraining the magnetic flux penetration generated. Superconductor 4 and annular permanent magnet 1
The widths of 1 in the axial direction are set to be substantially equal. Further, the superconductor 4 faces an annular permanent magnet 11 described later, and at a position where the magnetic flux from the annular permanent magnet enters a predetermined amount, at a position where the distribution of the invading magnetic flux does not change due to the rotation of the rotating body 7 described later, It is spaced apart. In such a superconducting bearing device 1, the superconductor 4 has the cooling case 2
It is cooled by the circulating refrigerant inside and kept in a superconducting state. In the superconducting state, the ring-shaped permanent magnet 1 of the rotating body 7
The magnetic flux from No. 1 enters the inside of the superconductor 4, and the inside magnetic flux distribution inside the superconductor 4 becomes constant due to the uniformly mixed normal conductor particles inside the superconductor 4. The annular permanent magnet 11 rotates while the rotor 7 is constrained by the superconductor 4 together with the annular permanent magnet 11 (pinning phenomenon) such that the annular permanent magnet 11 of the rotor 7 is penetrated through. Further, in the housing, a rotating body (rotating shaft in the embodiment) 7 is vertically arranged, a lower end side is inserted into the insertion hole 3A, and a magnet portion (permanent magnet portion in the embodiment) 8 is provided on the upper end side. It is provided. This magnet part 8
Is fixed to the rotating body 7 to form a rotating body portion A.

The magnet portion 8 is, in this embodiment, a magnet fixing portion 9
And an annular permanent magnet 11 and a reinforcing member 6.
The annular permanent magnet 11 is fixed to the cylindrical portion 10 of the magnet fixing portion 9 made of, for example, a non-magnetic reinforcing material such as titanium by press-fitting, a cooling fit, a shrink fit, or the like, or a clearance fit. . Further, in the annular permanent magnet 11, as shown in FIG. 2, a plurality (four in this embodiment) of arc-shaped magnet pieces 12, 12, ... Are sequentially bonded in the circumferential direction (direction along the circumference). It is composed of
In this embodiment, the arc-shaped magnet pieces 12, 12 ...
A cast ingot having a basic composition of Fe-B-Cu is hot-rolled to impart magnetic anisotropy, and further in an inert gas,
After heating, a permanent magnet bent in an arc shape was used. The mechanical strength of the permanent magnet produced by the hot rolling method is 3% higher than that of other sintered magnets due to the processing method.
The arc-shaped magnet piece 1 that has been bent more than twice as strongly
.. are bonded together without using any other adhesive material due to the grain boundary phase melted and exuded by heating in an inert gas. Therefore, the arc-shaped magnet piece 1
The strength of the bonding surface between the two, 12 ...
There is no difference from other parts such as 2, 12 ... The annular permanent magnet 11 manufactured in this way is, for example, CF
An external pressure is applied and tightened by a reinforcing member 6 made of a reinforcing material such as RP to form a magnet portion 8 capable of withstanding high speed rotation. In the method of strengthening the annular permanent magnet 11 by applying external pressure by the reinforcing member 6, press fitting is optimal when a metal material such as high-strength steel is used for the reinforcing member 6, and the reinforcing member 6 made of CFRP is used. In the same manner as above, there is a method of forming the reinforcing member 6 by pressing the carbon-containing fiber or rolling up the annular permanent magnet 11 while applying pressure. The external pressure of the reinforcing member 6 at this time needs to be set to be equal to or lower than the maximum compressive strength of the annular permanent magnet 11. By applying the external pressure of the annular permanent magnet 11 using the reinforcing member 6, the rotation limit of the rotating body 7 is increased, and high speed rotation is possible.

The magnetizing direction of the annular permanent magnet 11 is in the axial direction, as shown in FIG. In this embodiment, the magnetizing step is a step of manufacturing the annular permanent magnet 11 after the arc-shaped magnet pieces 12, 12 ...
carry out. Although a large force acts on the ring-shaped permanent magnet 11 in the magnetizing step, the ring-shaped permanent magnet 11 does not have a difference in strength between the bonded portion and the other portion, and forms a stable magnet portion 8. The Pr-Fe-B-Cu based hot rolling method permanent magnet used in this example is excellent in mechanical strength, and as described above, the bending method and the grain boundary phase bonding step are performed. Since the strength does not deteriorate even after passing through,
Although it is the most suitable magnet for use in this embodiment,
The same effect can be expected in all permanent magnets that can be processed as described above.

Further, in the step of adhering the arc-shaped magnet pieces 12, 12, ... To each other, the present embodiment was carried out while heating in an inert gas, but by activating the adhesion surface by plasma treatment or the like. A strong bond can be achieved even at room temperature.

Further, in the present embodiment, a method of tightening the annular permanent magnet 11 by the reinforcing member 6 was presented. Such a construction method can be performed by a hot rolling method, a bending method, and an adhesion by a grain boundary phase. High-strength ring-shaped permanent magnet 1
1 is a possible method. If permanent magnets that are divided and used with an adhesive or the like are used, there is a limit to the processing accuracy.Therefore, a gap is created between the permanent magnets, and stress is concentrated. Raising becomes difficult.

In the above embodiment, an example of using the indirect cooling method with the support 3 for cooling the superconductor 4 is shown.
In order to enhance the cooling efficiency, the support 3 may be hollow and a coolant such as liquid nitrogen may be flown inside. In that case, support 3
In order to prevent thermal leakage to the outside, it is desirable to use a material with low thermal conductivity.

(Second Embodiment) Next, a second embodiment will be described.
In each of the following embodiments, the same components as those in the first embodiment will be designated by the same reference numerals, and the description thereof will be omitted. FIG. 3 shows a main part of the superconducting magnetic bearing device of this embodiment, and FIG. 4 is a view taken along the line II-II of FIG. Similar to the first embodiment, the magnet portion 8 of the present embodiment is composed of an annular permanent magnet 11, which is composed of four arc-shaped magnet pieces 12, 12, ..., An annular member 13, a reinforcing member 6, and a magnet fixing portion 9. ing. The arc-shaped magnet pieces 12, 12 ... Give a magnetic anisotropy by hot rolling a cast ingot having a basic composition of Pr--Fe--B--Cu as in the magnet described in Example 1, and are further inert. A permanent magnet was used which was heated in gas and then bent into an arc shape. Due to the processing method, the permanent magnet produced by the hot rolling method is three times stronger than other sintered magnets. The bent arc-shaped magnet pieces 12, 12, ... Are arranged annularly so that the arc surfaces are in contact with the inside of the annular member 13 made of a metal material, and are melted by heating in an inert gas. The exuded grain boundary phase adhered to the annular member 13. The strength of the bonding surface between the arc-shaped magnet pieces 12, 12 ... And the annular member 13 is high, and the magnet portion 8 can be rotated at high speed.

The annular permanent magnet 1 manufactured in this way
1 is a reinforcing member 6 made of a reinforcing material such as CFRP.
By applying external pressure and tightening up, the strength is further increased, and further high speed rotation is possible.

The annular member 6 and the arc-shaped magnet pieces 12, 12 ...
In the bonding step of, by making the coefficient of thermal expansion of the material used for the annular member 6 lower than that of the annular permanent magnet 11, it is possible to further improve the adhesiveness. Since the bonding step is performed by utilizing the fact that the grain boundary phase melts at a high temperature, a temperature higher than the melting point of the grain boundary phase is required. R-Fe containing Pr-Fe-B-Cu system used in this example
The -B magnet alloy has almost no volume change up to the Curie temperature, which is a characteristic of a ferromagnetic material, but the coefficient of thermal expansion becomes remarkably high when it exceeds the grain boundary phase melting point. If the thermal expansion of the annular member 6 arranged on the outer peripheral portion of the annular permanent magnet 11 is smaller than that of the annular permanent magnet 11, pressure is generated at the contact interface between the arc-shaped magnet pieces 12, 12, ... Is effectively done. The annular member 6 is preferably made of heat-resistant steel, Mo alloy, ceramics or the like because of its low coefficient of thermal expansion. Annular member 6
The lower the coefficient of thermal expansion of the material to be used, the greater the force generated on the contact surface and the higher the effect of pressure welding. Further, a method of using low carbon steel for the annular member 6 and utilizing a rapid change in the thermal expansion coefficient due to the α-γ transformation of the low carbon steel at high temperature is also effective. Furthermore, by using an Invar alloy for the annular member 6, it is possible to improve the dimensional accuracy and reduce the risk of cracking that occurs during cooling.

In the bonding step of the permanent magnet arcuate magnet pieces 12, 12 ... And the annular member 6, the method of heating while being heated in an inert gas has been mainly described in the present embodiment. By activating the surfaces by plasma treatment or the like, strong bonding can be achieved even at room temperature.

The annular permanent magnet 11 is magnetized in the axial direction, as shown in FIG. In the present embodiment, the magnetizing step is performed after the arc-shaped magnet pieces 12, 12 ... And the annular member 6 are bonded and integrated in the manufacturing process of the annular permanent magnet 11. A large force acts on the annular permanent magnet 11 in the magnetizing step, but since the annular permanent magnet 11 is bonded to the annular member 6 with high strength, it forms a stable magnet portion 8.

(Embodiment 3) Next, an example in which annular permanent magnets are multiplexed will be shown. FIG. 5 shows a cross-sectional view of a magnet portion when the annular permanent magnets integrated by mutual adhesion of arc-shaped magnet pieces are multiplexed. As shown in Example 1, in the annular permanent magnets 11A, 11B, 11C and 11D, the arcuate magnet pieces divided into four are adhered to each other by the grain boundary phase, and the rotating body 7 (rotating shaft in the example) is used. It is composed of a concentrically multiplexed structure centered on. Annular permanent magnets 11A, 11B, 11C,
Annular members 13A, 13B inserted between 11D,
13C is made of a non-magnetic material, serves as a reinforcing measure for improving the rotational strength, and plays a role of preventing a magnetic short circuit of each annular permanent magnet. Annular permanent magnets 11A, 11B,
As shown in FIG. 5, the magnetizing directions of 11C and 11D are oriented in the axial direction, and the adjacent annular permanent magnets are arranged so as to have different polarities. The magnetizing step is performed by the annular permanent magnets 11A, 11
In the manufacturing process of B, 11C and 11D, the arc-shaped magnet pieces are adhered to each other and integrated, and then the annular permanent magnet 11A,
11B, 11C and 11D are magnetized respectively. After that, the annular permanent magnets 11A, 11B, 11C and 11D are sequentially multiplexed and assembled. A large force acts on the annular permanent magnets 11A, 11B, 11C, and 11D in the magnetizing process and the multiplex assembling process, but the annular permanent magnets 11A, 11B, 11C, and 11D have a strong surface in the bonded portion and other portions. There is no difference and there is no damage to the magnet portion 8.

The annular permanent magnet 1 manufactured in this way
1 is a reinforcing member 6 made of a reinforcing material such as CFRP.
By further tightening by applying an external pressure from the outer peripheral portion, the strength is further increased, and a further high speed rotation is possible.

(Embodiment 4) Next, an example in which an annular permanent magnet in which an arc-shaped magnet piece is adhered to and integrated with an annular member is multiplexed is shown. FIG. 6 shows a sectional view of the magnet portion of this embodiment. The annular permanent magnet 11A is made up of four arc-shaped magnet pieces,
The grain boundary phase adheres to the annular member 13A. Similarly, the ring-shaped permanent magnet 13B is bonded to the ring-shaped member 13B, the ring-shaped permanent magnet 13C is bonded to the ring-shaped member 13C, and the ring-shaped permanent magnet 13D is bonded to the ring-shaped member 13D by the grain boundary phase. Each of the bonded annular permanent magnets is a rotor 7
It has a concentric multiplex structure centered on the (rotational axis in the embodiment). Annular members 13A, 13B, 13C, 13D
Is made of a non-magnetic material, serves as a reinforcing measure for improving the rotational strength, and serves to prevent a magnetic short circuit of each of the annular permanent magnets. Annular permanent magnets 11A, 11B, 1
As shown in FIG. 6, the magnetizing directions of 1C and 11D are oriented in the axial direction, and the adjacent annular permanent magnets are arranged so as to have different polarities. The magnetizing step is performed by the annular permanent magnets 11A, 11
In the manufacturing process of B, 11C, 11D, the arc-shaped magnet pieces are bonded to the annular members 13A, 13B, 13C, 13D,
After being integrated, the annular permanent magnets 11A, 11B, 11C,
11D is magnetized. Then, the annular permanent magnet 11
A, 11B, 11C and 11D are sequentially multiplexed and assembled.

Further, similarly to the contents described in the second embodiment, the material used for the annular member is selected to be lower than the thermal expansion coefficient of the annular permanent magnet, so that the bonding process can be made more reliable. However, in order to prevent a magnetic short circuit between the adjacent annular permanent magnets, it is necessary to use a non-magnetic material.

The annular permanent magnet 1 manufactured in this way
1 is a reinforcing member 6 made of a reinforcing material such as CFRP.
By further tightening by applying an external pressure from the outer peripheral portion, the strength is further increased, and a further high speed rotation is possible.

(Embodiment 5) In this embodiment, the magnetic field strength is improved and the rotation strength is improved by using annular permanent magnets 11A and 11B which are adjacent to each other and are magnetized in the radial direction. . That is, as shown in FIG. 7, an annular member 13 made of a magnetic material is arranged between annular permanent magnets 11A and 11B that have different diameters and are given magnetic anisotropy in the radial direction. It has a structure. In addition, the annular permanent magnet 11A on the inner peripheral side and the annular permanent magnet 11 on the outer peripheral side
The same pole faces B with the annular member 13 interposed therebetween. In such a structure, the annular permanent magnets 11A, 11B
The magnetic flux from the N pole passes through the annular member 13 made of a magnetic material, appears on the surface of the annular permanent magnets 11A and 11B, and returns to the S pole of each of the annular permanent magnets 11A and 11B. At this time, since the magnetic flux from each annular permanent magnet 11 is narrowed down by the annular member, the surface magnetic flux density of the annular permanent magnets 11A and 11B is significantly improved.

The method of manufacturing each of the annular permanent magnets 11A and 11B is the same as the method described in the first embodiment, and a plurality of (four in this embodiment) arc-shaped magnet pieces are circumferentially (along the circumference).
It is configured by sequentially adhering to. In the present embodiment, the arc-shaped magnet piece is a cast ingot having a basic composition of Pr-Fe-B-Cu to give magnetic anisotropy by hot rolling, and is further heated in an inert gas to form a circle. A permanent magnet bent in an arc shape was used. Here, by setting the direction of magnetic anisotropy to the bending direction,
After bending, as shown in FIG. 8, it is given in the radial direction (arrow direction) of the arc of the arc-shaped magnet piece 12. Therefore, as shown in FIG. 9, the annular permanent magnet 11 formed in an annular shape by using four arc-shaped magnet pieces 12, 12 ... Is a so-called radial anomaly having magnetic anisotropy toward the center. It becomes a direction magnet. Due to the processing method, the permanent magnet produced by the hot rolling method is three times stronger than other sintered magnets. The bent arc-shaped magnet pieces 12, 12 ... Are bonded together by heating in an inert gas to melt and exude the grain boundary phase without using another adhesive material. ing. In this embodiment, the magnetizing step is performed by the annular permanent magnet 1
In the manufacturing process of 1A and 11B, the arc-shaped magnet pieces 12, 1
After bonding 2 ... to each other and integrating them, the annular permanent magnets 11A and 11B are individually implemented. Since a large repulsive force acts between the magnetized annular permanent magnets 11A and 11B,
When assembling the annular member 13 while sandwiching the annular member 13, a large pressure is required, but the annular permanent magnets 11A and 11B have high strength without any difference in strength between the bonded portion and other portions. , 11B are formed so that they are not damaged.

(Embodiment 6) Further, by disposing the annular member on the inner and outer diameters of the annular permanent magnet, it is possible to further improve the assembling property. As shown in FIG. 10, the annular member 1 made of a magnetic material is provided on the inner and outer diameter portions of the annular permanent magnet 11A.
3A and 13B are adhered. Similarly, an annular permanent magnet 1
Annular members 13C and 13D are provided on the inner and outer diameter portions of 1B, and annular members 13E and 13F are provided on the inner and outer diameter portions of the annular permanent magnet 11C.
However, the inner and outer diameter portions of the annular permanent magnet 11D are 13G and 1
3H is glued. Adjacent annular permanent magnets 11
The magnetizing directions of A, 11B, 11C and 11D are arranged so as to face each other in the radial direction with the same pole, and normally, as shown in the fifth embodiment, a large repulsive force acts between the annular permanent magnets. However, in this embodiment, the annular members 13A to 13H have the effect of relieving the repulsive force, so that the multiplex assembly can be easily performed. For example, when assembling the innermost annular permanent magnet 11A and the second annular permanent magnet 11B, first, the annular permanent magnet 11A is first fixed to the cylindrical portion 10 of the magnet fixing portion 9 by a press fitting method or the like, and then the annular permanent magnet 11A is fixed. 11B is inserted in the outer peripheral portion of the annular permanent magnet 11A. At this time, the flow of magnetic flux is facilitated by the annular members 13B and 13C arranged on the contact surfaces of the respective annular permanent magnets 11A and 11B, the repulsive force of attraction is reduced, and the assembly work is facilitated.
The attraction and repulsion force of a large-diameter permanent magnet that supports a heavy object such as a flywheel becomes enormous, and it can be said that facilitating assembly work is an extremely important effect.

(Embodiment 7) Although all of the above embodiments are examples of so-called axial superconducting magnetic bearings in which the superconductor portion and the permanent magnet portion are opposed to each other in the direction of the rotation axis, the present invention is not limited to the superconductor in the radial direction. An example of a so-called radial type superconducting magnetic bearing facing each other is shown.

FIG. 11 is a vertical cross-sectional view of the main part of an outer rotation type superconducting bearing device in which the rotating body 7 is arranged outside the superconducting portion 5. In a housing (not shown in FIG. 11), a support body 3 serving as a fixed portion and a rotating body 7 are housed, a superconductor 4 is arranged on the support body 3, and a magnet portion 8 includes two annular permanent magnets 11A and 11B. Ring member 1 made of magnetic material
3. The magnetic action is the same as that of the above-described sixth embodiment, and the magnetic flux generated from the annular permanent magnets 11A and 11B is narrowed by the annular member 13 to increase the magnetic flux density, and partly enters the superconductor 4 and becomes large. Generate pinning force. If you need to construct a bearing with a large diameter, or if you want to extract rotational output from the outer diameter,
The configuration according to No. 1 is preferable.

Furthermore, the annular permanent magnets 11A and 11B
Is formed by sequentially adhering a plurality (four in this embodiment) of arc-shaped magnet pieces in the circumferential direction (direction along the circumference), as in the first embodiment. The arc-shaped magnet piece is Pr-F.
A cast ingot having a basic composition of e-B-Cu was hot-rolled to impart magnetic anisotropy, and after heating in an inert gas, a permanent magnet bent in an arc shape was used. . The permanent magnet produced by the hot rolling method is three times or more stronger than other sintered magnets due to the processing method.
The arc-shaped magnet pieces that have been subjected to bending are adhered to each other without using any other adhesive material due to the grain boundary phase melted and exuded by heating in an inert gas. The annular permanent magnets 11A and 11B manufactured in this manner form a magnet portion 8 that can endure high speed rotation by being tightened by an external pressure by a reinforcing member 6 made of a reinforcing material such as CFRP.

The magnetizing direction of the annular permanent magnet 11 is in the axial direction, as shown in FIG. In the present embodiment, the magnetizing step is carried out after the arc-shaped magnet pieces are bonded and integrated with each other in the manufacturing steps of the annular permanent magnets 11A and 11B. Although a large force acts on the annular permanent magnets 11A and 11B in the magnetizing step and the assembling step after the magnetizing, the annular permanent magnet 11 has no difference in strength between the bonded portion and other portions, and the annular permanent magnet 11A , 11B is not damaged. Pr-Fe-B-C used in this example
The permanent magnet produced by the u-based hot rolling method is excellent in mechanical strength, and does not deteriorate in its strength even after the bending method and the bonding step by the grain boundary phase as described above. Although it is the most suitable magnet for use in this embodiment, the same effect can be expected in all permanent magnets that can be processed by the above-mentioned processing method.

With the structure of this embodiment, it is possible to improve the radial rigidity, which is an important factor for the bearing, and to increase the bearing load of the bearing. That is, if the outer diameter of the bearing is constrained so that it cannot be increased in the radial direction, if the annular permanent magnets are laminated in the axial direction, the loading force can be increased without changing the outer diameter. You can This is extremely effective for a superconducting magnetic bearing device for flywheels, which requires high speed rotation and high loading force.

In the first to seventh embodiments described above,
In the superconducting bearing device, the superconductor portion 5 is provided in the fixed body portion B, and the magnet portion 8 is provided in the rotating body portion A, respectively. However, the present invention, conversely, the superconductor portion 5 is provided in the rotating body portion. Even if the magnet portion 8 is provided in A and the magnet portion 8 is provided in the fixed body portion B, the same operational effect can be obtained. Also, an example using a Pr-Fe-B-Cu magnet as the magnet is shown, but the present invention is not limited to this, and ferrite, alnico, neodymium, samarium, etc. may be used.
Of course, all other permanent magnets can be used, and all those that generate magnetic flux, such as electromagnets and superconducting coils, are also applicable. In addition, the magnetic flux is contained by the pinning effect, so to speak, a superconductor itself. Can also be used as a fixed body part and a magnet installed on the fixed body part. Further, as for the superconductor, the yttrium high temperature superconductor has been shown as an example, but all of the (RE-Ba-Cu-O) -based materials including a rare earth-based element that can have a restoring force with a magnet are also used. The superconductor of is applicable. Where RE is Y, Sm, Eu, Nd, D
It represents one or more elements selected from the group of elements consisting of y, Ho, Er and Yb.

[0041]

As described above, according to the present invention, in this type of superconducting magnetic bearing device, arcuate magnets are adhered to each other to form an integral annular permanent magnet, which is then magnetized and strengthened from the outer peripheral portion. High-speed rotation is possible because external pressure is applied for reinforcement. Further, since the arcuate magnet is bonded to the annular member to form the integral annular magnet, the rotation strength can be further improved. Further, by using a material having a coefficient of thermal expansion lower than that of the arc-shaped magnet for the annular member, the adhesiveness between the annular member and the arc-shaped magnet can be further improved, and high speed rotation can be achieved. In addition, when forming the multi-layered annular magnet,
The use of an integral annular magnet made it easy to assemble. Further, by performing bending in the radial direction and using the radial magnetic anisotropic magnet, it is possible to realize a rotating body having high magnetic field strength and high mechanical strength. Further, by bonding the annular magnetic body to the inner and outer diameters of the radial magnetic anisotropic magnet, the multiplex assembling process is facilitated. Further, by adopting a radial bearing structure, high rigidity can be achieved.

That is, the present invention can be applied to a fluid machine or a machine tool that requires high-speed rotation, an electric power storage device that converts surplus electric power into kinetic energy of a flywheel and stores it, and particularly to a large system that requires a loading force. It is possible.

[Brief description of drawings]

1 is a sectional view taken along the line I-I in FIG. 2 showing a main part of a superconducting magnetic bearing device according to a first embodiment of the invention.

FIG. 2 is a view taken along the line II-II in FIG. 1 showing the bottom surface of the permanent magnet portion according to the first embodiment of the invention.

FIG. 3 is a sectional view taken along the line I-I in FIG. 4 showing a main part of a superconducting magnetic bearing device according to the second embodiment of the invention.

FIG. 4 is a view taken along the line II-II in FIG. 3 showing the bottom surface of the permanent magnet portion according to the second embodiment of the present invention.

FIG. 5 is a longitudinal sectional view showing a main part of a permanent magnet part according to a third embodiment of the present invention.

FIG. 6 is a longitudinal sectional view showing a main part of a permanent magnet part according to a fourth embodiment of the present invention.

FIG. 7 is a vertical cross-sectional view showing a main part of a permanent magnet part according to a fifth embodiment of the present invention.

FIG. 8 is a perspective view of an arcuate magnet piece according to a fifth embodiment of the present invention.

9 is a perspective view related to the fifth embodiment of the present invention in which the arc-shaped magnet of FIG. 8 is formed into an annular shape.

FIG. 10 is a longitudinal sectional view showing a main part of a permanent magnet part according to a sixth embodiment of the present invention.

FIG. 11 is a longitudinal sectional view of a main part of a superconducting bearing device according to a seventh embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Superconducting bearing device 2 Cooling case 3 Support body 4 Superconductor 5 Superconductor part 6 Reinforcing member 7 Rotating body 8 Magnet part 9 Magnet fixing part 10 Cylindrical part 11, 11A, 11B, 11C, 11D Annular permanent magnet 12 Arc-shaped magnet piece 13, 13A, 13B, 13C, 13D, 13E, 13
F, 13G, 13H Ring magnetic body A Rotating body portion B Fixed body portion

Claims (9)

[Claims] 1. A superconductor part mounted on one of a rotating body part and a fixed body part and a magnet part mounted on the other, the superconductor part having a restoring force between the superconductor part and the magnet part. In a superconducting magnetic bearing device of a type that is composed of a superconductor and a support that supports the superconductor, and the magnet portion is provided with an annular magnet having the axis of the rotor portion as a concentric axis, the magnet portion Is a combination of a plurality of arc-shaped magnets manufactured by hot bending, to form an integral annular magnet structure in which the arc-shaped magnets adjacent to each other in the circumferential direction are adhered, and a reinforcing member is arranged on the outer periphery of the magnet portion. A superconducting magnetic bearing device characterized by the above. 2. A superconductor part mounted on one of the rotating body part and the fixed body part, and a magnet part mounted on the other, the superconductor part having a restoring force between the superconductor part and the magnet part. In a superconducting magnetic bearing device of a type that is composed of a superconductor and a support that supports the superconductor, and the magnet portion is provided with an annular magnet having the axis of the rotor portion as a concentric axis, the magnet portion Is formed by a plurality of arc-shaped magnets manufactured by hot bending and an annular member circumscribing the outer peripheral portion of the arc-shaped magnet, and the arc-shaped magnets are annularly arranged inside the annular member. At the same time, a superconducting magnetic bearing device having an integral annular magnet structure in which the annular member and the annular magnet are bonded together. 3. The thermal expansion coefficient of the annular member is lower than the thermal expansion coefficient of the arc-shaped magnet.
The superconducting magnetic bearing device described. 4. The magnet portion is composed of a plurality of integral annular magnets having different diameters, and the plurality of integral annular magnets are formed by a multiplex structure in which the shaft center of the rotating body portion is concentric. The superconducting magnetic bearing device according to claim 1 or 2. 5. A superconductor portion mounted on one of the rotating body portion and the fixed body portion and a magnet portion mounted on the other, the superconductor portion having a restoring force between the superconductor portion and the magnet portion. In a superconducting magnetic bearing device of a type that is composed of a superconductor and a support that supports the superconductor, and the magnet portion is provided with an annular magnet having the axis of the rotor portion as a concentric axis, the magnet portion Is manufactured by hot bending, combining a plurality of arc-shaped magnets that are given magnetic anisotropy in the radial direction, and is an integral annular magnet structure in which the arc-shaped magnets that are adjacent to each other in the circumferential direction are bonded together, As the integrated annular magnet, two or more integrated annular magnets having at least different diameters that are magnetized so that the same poles face each other in the radial direction are arranged, and an annular member is provided between the annular magnets that are adjacent in the radial direction, It is characterized by arranging a reinforcing member on the outer periphery of the magnet part Superconducting magnetic bearing device. 6. A superconductor part mounted on one of the rotating body part and the fixed body part and a magnet part mounted on the other, the superconductor part having a restoring force between the superconductor part and the magnet part. In a superconducting magnetic bearing device of a type that is composed of a superconductor and a support that supports the superconductor, and the magnet portion is provided with an annular magnet having the axis of the rotor portion as a concentric axis, the magnet portion Is manufactured by hot bending, combining a plurality of arc-shaped magnets that are given magnetic anisotropy in the radial direction, and is an integral annular magnet structure in which the arc-shaped magnets that are adjacent to each other in the circumferential direction are bonded together, As the integrated annular magnet, two or more integrated annular magnets having at least different diameters that are magnetized so that the same poles face each other in the radial direction are arranged, and an annular member is provided between the annular magnets that are adjacent in the radial direction, The annular members have a structure in which they are doubly stacked in the radial direction. A superconducting magnetic bearing device is characterized in that a reinforcing member is arranged on the outer periphery of the magnet portion. 7. A superconductor portion mounted on one of the rotating body portion and the fixed body portion and a magnet portion mounted on the other, the superconductor portion having a restoring force between the superconductor portion and the magnet portion. A superconductor and a support for supporting the superconductor, the magnet portion is provided with an annular magnet having the axis of the rotor portion as a concentric axis, the annular magnet and the superconductor portion, In a superconducting magnetic bearing device of a type arranged so as to face each other at intervals in the radial direction of the rotating body portion, the magnet portion is a combination of a plurality of arc-shaped magnets manufactured by hot bending, and a circumferential direction. Is an integrated annular magnet structure in which the arc-shaped magnets adjacent to each other are adhered to each other, and as the integrated annular magnet, at least two integrated annular magnets are magnetized so that the same poles face each other in the axial direction of the same diameter. The axially adjacent integral annular magnet A superconducting magnetic bearing device characterized in that an annular member is provided between stones. 8. The magnet portion is magnetized after forming the integral annular magnet structure.
The superconducting magnetic bearing device described. 9. The superconducting magnetic bearing device according to claim 1, wherein mechanical strength of a bonding portion between the arc-shaped magnets is equal to that of the arc-shaped magnet alone.