JPH08177857A - Superconductive bearing device - Google Patents

Abstract

PURPOSE: To increase a load capacity in axial direction by providing annular fixed permanent magnets which energize rotating permanent magnets upward by magnetic repulsion at a fixed part positioned lower than the rotating permanent magnets and superconductive body. CONSTITUTION: A superconductive bearing device is provided with multiple annular permanent magnets 10 in which rotating permanent magnet parts 3 are arranged concentrically in radial direction. Also magnetic poles are formed on the inner and outer periphery sides of each permanent magnet 10, the magnetic poles of two permanent magnets 10 adjacent to each other in radial direction are the same each other and, in addition, a yoke member 11 comprising a ferromagnetic body is inserted between two permanent magnets 10 adjacent to each other in radial direction. As a result, magnetic flux is centralized locally to an area facing a superconductive body 14 of the yoke member 11, and magnetic flux invading into the superconductive body 14 becomes larger so as to increase the load capacity and rigidity of the superconductive bearing device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used, for example, in fluid machines and machine tools that require high-speed rotation, electric power storage devices that convert surplus electric power into rotational kinetic energy of flywheels, and store it, or gyroscopes. More particularly, the present invention relates to a superconducting bearing device that supports a rotating body that rotates about a vertical axis.

[0002]

2. Description of the Related Art In recent years, a superconducting bearing device capable of supporting a rotating body in a non-contact state has been developed as a bearing device capable of high-speed rotation and high rigidity of the rotating body.

As a superconducting bearing device for supporting a rotating body rotating about a vertical axis in a non-contact manner, an annular rotating permanent magnet is provided on an upwardly or downwardly facing surface of the rotating body orthogonal to the rotation axis of the rotating body. The distribution is symmetric with respect to the axis of rotation, and the magnetic flux distribution around the axis of rotation is arranged so that it does not change due to rotation. It is considered that it is arranged at a position where the distribution of the invading magnetic flux does not change due to the rotation of the rotating body so as to face the rotating permanent magnet in the direction of the rotation axis.

In this superconducting bearing device, the magnetic flux generated from the rotating permanent magnet is made to enter the inside of the superconductor to be restrained,
As a result, the rotating body is supported by the so-called pinning force in a non-contact state with respect to the fixed portion in the axial direction and the radial direction.

[0005]

In the above superconducting bearing device, the rotating body can be supported in both the axial direction and the radial direction by the pinning force of the magnetic flux restrained by the superconductor, but especially in the axial direction (gravity direction). There is a limit to the supporting force (load capacity) in the direction), and there is a problem that a rotating body having a large weight cannot be supported.

The object of the present invention is to solve the above problems,
An object of the present invention is to provide a superconducting bearing device capable of improving load capacity in the axial direction.

[0007]

A superconducting bearing device according to the first invention comprises a rotating permanent magnet provided on a rotating body that rotates about a vertical axis, and a superconductor provided on a fixed portion. A superconducting bearing device for supporting a rotating body in a non-contact manner,
On the surface of the rotating body orthogonal to the rotating shaft center of the rotating body, an annular rotating permanent magnet has a magnetic flux distribution symmetrical with respect to the rotating shaft center, and the magnetic flux distribution around the rotating shaft center changes due to rotation. So that the superconductor is a separated position where the magnetic flux of the rotating permanent magnet penetrates by a predetermined amount and the distribution of the magnetic flux entering does not change due to the rotation of the rotating body.
In a superconducting bearing device arranged to face the rotating permanent magnet in the direction of the rotation axis, the rotating permanent magnet is biased upward by a magnetic repulsive force to a fixed portion below the rotating permanent magnet and the superconductor. An annular fixed permanent magnet is provided.

In the superconducting bearing device according to the second aspect of the invention, a rotating permanent magnet provided on a rotating body that rotates about a vertical axis and a superconductor provided on a fixed portion support the rotating body in a non-contact manner. In the superconducting bearing device, an annular rotating permanent magnet is provided on the surface of the rotating body orthogonal to the rotating shaft center of the rotating body, and the magnetic flux distribution is symmetric with respect to the rotating shaft center, and the rotating shaft center. It is arranged so that the magnetic flux distribution around it does not change due to rotation, and the superconductor is a separated position where the magnetic flux of the rotating permanent magnet penetrates by a predetermined amount, and the distribution of the invading magnetic flux does not change due to the rotation of the rotating body. In the superconducting bearing device arranged to face the rotating permanent magnet in the direction of the rotation axis, the rotating permanent magnet is upwardly moved by a magnetic attraction force to a fixed portion above the rotating permanent magnet and the superconductor. Ring-shaped It is characterized in that the constant permanent magnets are provided.

[0009]

According to the first aspect of the invention, the rotating permanent magnet provided on the rotating body is urged upward by the magnetic repulsive force from the fixed permanent magnet provided on the fixed portion, thereby reducing the weight of the rotating body. Since the part is supported, the load capacity in the axial direction is improved.

According to the second aspect of the present invention, the rotating permanent magnet provided on the rotating body is biased upward by the magnetic attraction force from the fixed permanent magnet provided on the fixed portion, whereby the weight of the rotating body is reduced. Since the part is supported, the load capacity in the axial direction is improved.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows the main part of the superconducting bearing device of the first embodiment.

In FIG. 1, a superconducting bearing device is a non-contact support for a rotating body (1) that rotates about a vertical axis in a fixed housing (fixed portion) (2). It has a magnet part (3), a superconductor part (4) and a fixed permanent magnet part (5).

The rotary body (1) comprises a vertical rotary shaft (6) and a disk-shaped rotary member (7) concentrically fixed to the rotary shaft (6), such as a flywheel or a flange. The rotating body (1) can be rotated at a high speed by a high-frequency motor (not shown) or the like.

The rotating permanent magnet section (3) is provided on the lower surface of the rotating member (7) orthogonal to the rotation axis (A) of the rotating body (1). A plurality of annular recessed grooves (9) partitioned by a circular partition wall (8) are concentrically formed on the lower surface of the rotating member (7). The rotating member (7) may be integrally formed as a single member as a whole, or may be formed by combining a plurality of members, but at least the portion where the groove (9) is formed is, for example, It is made of non-magnetic material such as aluminum alloy and non-magnetic stainless steel. An annular rotating permanent magnet (10) and an annular yoke member (11) made of a ferromagnetic material are fitted and fixed in each recess (9) so that the permanent magnet (10) is on the outside. There is. The outer peripheral part of the permanent magnet (10) is a groove.
It is press fitted into the outer peripheral wall of (9) or the inner peripheral part of the partition wall (8). The inner peripheral portion of the yoke member (11) has a groove.
It is press-fitted into the partition wall (8) on the inner peripheral side of (9) or the outer peripheral portion of the wall. And a permanent magnet in the same groove (9)
The inner peripheral portion of (10) and the outer peripheral portion of the yoke member (11) are loosely fitted to each other, and there is little or little gap between them. As shown in detail in FIG. 2, each permanent magnet (10) is circumferentially equally divided into a plurality of segments (10a), and magnetic poles are formed on the inner peripheral side and the outer peripheral side. The permanent magnets (10) are arranged so that the magnetic poles of the two permanent magnets (10) adjacent in the radial direction have the same polarity. That is, from the inside 1,
The third and fifth permanent magnets (10) have an S pole on the inner circumference side and an N pole on the outer circumference side.
The second and fourth permanent magnets (10) have N poles on the inner circumference side and S poles on the outer circumference side. The permanent magnet (10) is divided into a plurality of segments (10a) in the circumferential direction.
This is because if the permanent magnet is an annular one piece, magnetic poles cannot be formed on the inner peripheral portion and the outer peripheral portion thereof. Furthermore, the phases of the divided surfaces of the adjacent annular permanent magnets (10) are shifted so that they do not overlap. This is to suppress the unevenness of the distribution state of the magnetic flux on the split surface as much as possible. Since the permanent magnet (10) has an annular shape and is concentrically arranged with respect to the rotation axis (A), the magnetic flux distribution of the permanent magnet (10) is symmetrical with respect to the axis (A), and The magnetic flux distribution around the axis (A) does not change due to rotation.

The superconductor part (4) is arranged so that it faces the lower surface of the rotating permanent magnet part (3) at a predetermined interval.
It has an annular cooling case (12) fixed to (2).
The cooling case (12) is made of a non-magnetic material such as copper alloy or non-magnetic stainless steel, and is fixed to the housing (2) via a heat insulating material (13). An annular superconductor (14) is fixedly arranged in the space inside the cooling case (12). Although illustration is omitted, the space in the cooling case (12) is connected to the cooling device via the cooling fluid supply pipe and the discharge pipe, and by this cooling device, a cooling fluid such as liquid nitrogen is supplied to the cooling pipe. The superconductor (14) is cooled by being circulated through the space in the cooling case (12) and the discharge pipe. The superconductor (14) is a type 2 superconductor, and is a yttrium-based high temperature superconductor such as YB.
In the bulk of a ₂ Cu ₃ O _7-x , a normal conductor (Y
₂ Ba ₁ Cu ₁ ) is uniformly mixed, and has the property of internally confining the magnetic flux emitted from the permanent magnet (10) in the temperature environment where the second-class superconducting state appears. . And, the superconductor (14) is at the separated position where the magnetic flux of the permanent magnet (10) penetrates by a predetermined amount, and the rotating body (1).
Is arranged so as to face the permanent magnet (10) at a position where the distribution of the invading magnetic flux does not change by the rotation of.

The fixed permanent magnet part (5) is placed under the superconductor part (4) so as to face the rotating permanent magnet part (3).
It is fixedly installed in (2). Fixed permanent magnet part (5)
The disk-shaped annular flange member (15) made of a non-magnetic material is fixed to the housing (2). Flange member (15)
An annular recess (16) is formed on the upper surface of the, leaving the outer peripheral portion thereof, and in this recess (16), an annular yoke member (17) made of a plurality of ferromagnetic materials and between them are formed. A plurality of annular fixed permanent magnets (18) sandwiched between are fitted and fixed.
The number of fixed permanent magnets (18) is the same as the number of rotating permanent magnets (10), and the fixed permanent magnets (18) are arranged so as to substantially face the rotating permanent magnets (10). The fixed permanent magnet (18) has the same structure as the rotating permanent magnet (10) and is equally divided into a plurality of segments (18a) in the circumferential direction. In addition, the fixed permanent magnet (1
The arrangement of the magnetic poles of 8) is the same as that of the rotating permanent magnet (10), and the magnetic poles of the upper and lower permanent magnets (10) and (18) have the same polarity and repel each other.

When starting the operation of the rotating body (1), first, by using an appropriate initial positioning device or the like, lift the rotating body (1) in a stopped state to a predetermined position, and then rotate the rotating body (1). Performs initial positioning in the axial and radial directions of. Then, the cooling fluid is circulated in the cooling case (12) of the superconducting bearing device by the cooling device to cool the superconductor (14) and hold it in the second type superconducting state. Then, the rotating permanent magnet
Most of the magnetic flux generated from (10) enters the inside of the superconductor (14) and is restricted (pinning phenomenon). Here, since the normal conductor particles are uniformly mixed in the superconductor (14), the distribution of the magnetic flux penetrating into the superconductor (14) becomes constant, and therefore the superconductor (14) ), The rotating body (1) is restrained together with the rotating permanent magnet (10). Therefore, the rotating body (1) is supported in the axial direction and the radial direction in an extremely stable state. At this time, the magnetic flux penetrating the superconductor (14) does not become a resistance that hinders rotation as long as the magnetic flux distribution is uniform and unchanged with respect to the rotation axis (A). When the rotating body (1) is thus supported by the superconducting bearing device, the supporting of the rotating body (1) by the initial positioning device is eliminated. When there is no support by the initial positioning device, the rotating body (1) slightly descends due to its own weight, but stops at a position where the downward force due to its own weight and the axial supporting force of the superconducting bearing device are balanced.
As a result, the rotating body (1) is non-contact supported by the superconducting bearing device. At this time, the rotating permanent magnet (10) of the superconducting bearing device receives an upward repulsive force from the fixed permanent magnet (5), thereby supporting a part of the weight of the rotating body (1). When the rotating body (1) is supported in a non-contact manner, the electric motor is started and the rotating body (1) is rotated. During rotation, the rotating body (1) is supported in the axial direction and the radial direction by the pinning force of the magnetic flux penetrating the superconductor (14), and continues stable rotation.

In the above superconducting bearing device, the rotating permanent magnet section (3) is provided with a plurality of annular permanent magnets (10) arranged concentrically in the radial direction, and the inner peripheral side of each permanent magnet (10). And a magnetic pole is formed on the outer peripheral side, the magnetic poles of two permanent magnets (10) adjacent in the radial direction are the same as each other, and a ferromagnetic material is provided between the two permanent magnets (10) adjacent in the radial direction. Since the yoke member (11) is sandwiched, the magnetic flux is locally concentrated in the portion of the yoke member (11) facing the superconductor (14), and as a result, enters the superconductor (14). The increased magnetic flux improves the load capacity and rigidity of the superconducting bearing device.

However, the rotating permanent magnet (10) and the fixed permanent magnet (18) may have magnetic poles formed at both ends in the axial direction. In this case, the permanent magnet (1
(0) (18) can be made into a one-piece ring.

In the above superconducting bearing device, in the rotating permanent magnet part (3), the annular permanent magnet (10) is provided in each of the plurality of concentric annular recessed grooves (9) on the end face of the rotating member (7). Since the magnet and the yoke member (11) are assembled one by one, a permanent magnet
The dimensional control and assembly of the (10) and the yoke member (11) are easy, the deformation of the permanent magnet (10) due to centrifugal force during high-speed rotation is small, and therefore the operation of the superconducting bearing device is stable and The permanent magnet (10) does not cause centrifugal damage. If a plurality of annular yoke members and annular permanent magnets are alternately press-fitted into one groove on the end surface of the rotary member, the outer yoke member or permanent magnet is less likely to undergo centrifugal expansion. The centrifugal expansion of the inner permanent magnet or the yoke member is small, but the centrifugal expansion of a certain yoke member or permanent magnet easily causes the centrifugal expansion of the inner permanent magnet or yoke member. Swelling increases. Therefore, for the inner permanent magnet or the yoke member, it is necessary to set a large tightening margin in consideration of the centrifugal expansion of the outer yoke member or the permanent magnet, and it is difficult to manage the dimensions and the assembly is also difficult. . Further, since the inner permanent magnet has a large centrifugal expansion, that is, a large displacement in the radial direction, the radial position of the permanent magnet changes between the initial positioning when the rotor is stopped and the high speed rotation. Especially when the permanent magnet is divided into a plurality of segments in the circumferential direction, a circumferential gap may occur between these segments. Therefore, the magnetic flux distribution due to the permanent magnet changes between the initial positioning and the high-speed rotation, or the magnetic flux distribution around the rotation axis becomes uneven, and the operation of the superconducting bearing device becomes unstable. In addition, especially for the inner permanent magnet, a large centrifugal expansion occurs, which may cause centrifugal destruction. On the other hand, in the rotating permanent magnet part (3) of the above superconducting bearing device, each permanent magnet (10) is attached to the wall of the rotating member (7) or the inner peripheral part of the partition wall (8) with small centrifugal expansion. Since it is press-fitted, the tightening margin can be reduced, and the permanent magnet
The dimensional control and assembly of (10) are easy, the centrifugal expansion of the permanent magnet (10) is small, and the permanent magnet (10) does not undergo centrifugal breakdown. Since the permanent magnet (10) has a small centrifugal expansion, the permanent magnet (10) has a plurality of segments (10a) in the circumferential direction.
Even if the permanent magnet (10) is divided into two, the radial displacement of the permanent magnet (10) is small, and no circumferential gap is formed between the segments (10a). Therefore, the magnetic flux distribution due to the permanent magnet (10) does not change between initial positioning and high-speed rotation, and the magnetic flux distribution around the rotation axis does not become uneven, and the operation of the superconducting bearing device is prevented. stable.
Furthermore, each yoke member (11) is a rotating member with small centrifugal expansion.
Since they are press-fitted into the wall of (7) or the outer peripheral portion of the partition wall (8), the tightening margin can be reduced, and the dimensional control and assembly of the yoke member (11) are easy. In addition, the yoke member (11) is a permanent magnet (1) in the same groove (9).
It may be press-fitted inside 0). Even in this case, as for the dimensional control of the yoke member (11), only the small centrifugal expansion of the one permanent magnet (10) on the outer side of the yoke member (11) needs to be taken into consideration, so that the tightening allowance can be reduced. Easy dimensional control and assembly.

Even when the rotating permanent magnet (10) has magnetic poles formed at both ends in the axial direction as described above,
It is desirable to mount the permanent magnets (10) one by one in a plurality of annular recesses (9) formed in the rotating member (7).
If magnetic poles are formed on both ends of the permanent magnet (10) in the axial direction, it is not necessary to provide a yoke member between them, so only the permanent magnet (10) should be attached to the groove (9). Good. Therefore, as in the case of the above embodiment, the permanent magnet
Dimensional control and assembly of (10) are easy, and deformation of the permanent magnet (10) due to centrifugal force during high-speed rotation is small, so the operation of the superconducting bearing device is stable and the permanent magnet (10) It does not cause centrifugal breakdown. If the permanent magnet (10) is installed in the groove (9), the partition wall (8) made of non-magnetic material exists between the two permanent magnets (10) that are adjacent in the radial direction. There is no need to assemble a non-magnetic ring separately.

FIG. 3 schematically shows the main part of the superconducting bearing device of the second embodiment.

In the case of the second embodiment, the rotating permanent magnet part (20) is provided on the upper surface of the rotating member (7), and the superconductor part (21) is arranged above the rotating permanent magnet part (20). There is. The rotating permanent magnet section (20) and the superconductor section (21) correspond to the rotating permanent magnet section (3) and the superconductor section (4) of the first embodiment which are turned upside down. The same reference numerals are given to the parts, and detailed description is omitted.

The fixed permanent magnet portion (22) is arranged so as to face the rotating permanent magnet portion (3) from below the rotating member (7). Since the structure of the fixed permanent magnet part (22) is the same as that of the fixed permanent magnet part (5) of the first embodiment, the corresponding parts are designated by the same reference numerals and detailed description thereof is omitted.

Also in the case of the second embodiment, the fixed permanent magnet portion (22)
The permanent magnet (18) of the rotating permanent magnet part (2)
The permanent magnet (10) of (0) is urged upward, and
Part of the weight of (1) is supported.

Others are the same as in the case of the first embodiment, and the same parts are designated by the same reference numerals.

FIG. 4 schematically shows the main part of the superconducting bearing device of the third embodiment.

In the case of the third embodiment, the structure and arrangement of the rotating permanent magnet part (25) and the superconductor part (26) are the same as those of the first embodiment, and the corresponding parts are designated by the same reference numerals. Detailed description is omitted.

The fixed permanent magnet portion (27) is arranged so as to face the rotating permanent magnet portion (25) from above the rotating member (7). Since the fixed permanent magnet portion (27) is the fixed permanent magnet portion (5) of the first embodiment which is turned upside down, the corresponding portions are designated by the same reference numerals and detailed description thereof is omitted.

In the case of the third embodiment, the arrangement of the magnetic poles of the permanent magnets (18) of the fixed permanent magnet portion (27) is the same as that of the permanent magnets (18) of the fixed permanent magnet portion (5) of the first embodiment. It is the opposite of the arrangement. Therefore, the arrangement of the magnetic poles of the permanent magnet (18) of the fixed permanent magnet portion (27) is opposite to that of the permanent magnet (10) of the rotating permanent magnet portion (25), and the permanent magnets (18) ( The magnetic poles of 10) are opposite magnetic poles and are attracted to each other. And
The permanent magnet (10) of the rotating permanent magnet section (25) is biased upward by the magnetic attraction force of the permanent magnet (18) of the fixed permanent magnet section (27), which causes a part of the weight of the rotating body (1). Is being supported. In this case, the permanent magnet (18) of the fixed permanent magnet part (27) and the permanent magnet (10) of the rotating permanent magnet part (25) attract each other, so that not only the load capacity in the axial direction is improved but also the radial direction is increased. The load capacity in the direction is also improved.

Others are the same as in the case of the first embodiment, and the same parts are designated by the same reference numerals.

FIG. 5 schematically shows the main part of the superconducting bearing device of the fourth embodiment.

In the case of the fourth embodiment, the rotary permanent magnet part (30) and the superconductor part (31) have the same structure and arrangement as those of the second embodiment, and the corresponding parts are designated by the same reference numerals. Detailed description is omitted.

The fixed permanent magnet part (32) is arranged so as to face the rotating permanent magnet part (30) from above the superconductor part (31). Since the structure of the fixed permanent magnet part (32) is the same as that of the fixed permanent magnet part (27) of the third embodiment, corresponding parts are designated by the same reference numerals and detailed description thereof is omitted.

Also in the case of the fourth embodiment, the fixed permanent magnet portion (32)
The permanent magnet (18) of the
The permanent magnet (10) of (0) is urged upward, and
Part of the weight of (1) is supported.

Others are the same as in the case of the third embodiment, and the same parts are denoted by the same reference numerals.

[0038]

According to the superconducting bearing device of the present invention, as described above, a part of the weight of the rotating body can be supported by the magnetic repulsive force or the magnetic attractive force of the fixed permanent magnet, and therefore, the axial direction. The load capacity is improved, and it is possible to support a heavy rotating body that cannot be supported by a normal superconducting bearing device in which a rotating permanent magnet and a superconductor are simply opposed to each other. Moreover, since the rotating permanent magnet originally required for the superconducting bearing device is used as one permanent magnet for obtaining the magnetic repulsive force or the magnetic attractive force, it suffices to add the fixed permanent magnet to the fixed portion. As a result, an increase in space and cost can be reduced.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a main part of a superconducting bearing device showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a longitudinal sectional view of a main part of a superconducting bearing device showing a second embodiment of the present invention.

FIG. 4 is a vertical cross-sectional view of a main part of a superconducting bearing device showing a third embodiment of the present invention.

FIG. 5 is a vertical cross-sectional view of a main part of a superconducting bearing device showing a fourth embodiment of the present invention.

[Description of symbols] (1) Rotating body (2) Fixed housing (fixed part) (10) Rotating permanent magnet (14) Superconductor (18) Fixed permanent magnet (A) Rotation axis

Claims (2)

[Claims] 1. A superconducting bearing device for supporting a rotating body in a non-contact manner by a rotating permanent magnet provided on a rotating body rotating about a vertical axis and a superconductor provided on a fixed portion,
On the surface of the rotating body orthogonal to the rotating shaft center of the rotating body, an annular rotating permanent magnet has a magnetic flux distribution symmetrical with respect to the rotating shaft center, and the magnetic flux distribution around the rotating shaft center changes due to rotation. So that the superconductor is a separated position where the magnetic flux of the rotating permanent magnet penetrates by a predetermined amount and the distribution of the magnetic flux entering does not change due to the rotation of the rotating body.
In the superconducting bearing device which is arranged so as to face the rotating permanent magnet in the direction of the rotation axis, the rotating permanent magnet is biased upward by the magnetic repulsive force to the fixed portion below the rotating permanent magnet and the superconductor. A superconducting bearing device, wherein an annular fixed permanent magnet is provided. 2. A superconducting bearing device for supporting a rotating body in a non-contact manner by a rotating permanent magnet provided on a rotating body rotating about a vertical axis and a superconductor provided on a fixed portion,
On the surface of the rotating body orthogonal to the rotating shaft center of the rotating body, an annular rotating permanent magnet has a magnetic flux distribution symmetrical with respect to the rotating shaft center, and the magnetic flux distribution around the rotating shaft center changes due to rotation. So that the superconductor is a separated position where the magnetic flux of the rotating permanent magnet penetrates by a predetermined amount and the distribution of the magnetic flux entering does not change due to the rotation of the rotating body.
In the superconducting bearing device which is arranged so as to face the rotating permanent magnet in the direction of the rotation axis, the rotating permanent magnet is biased upward by a magnetic attraction force to a fixed portion above the rotating permanent magnet and the superconductor. A superconducting bearing device, wherein an annular fixed permanent magnet is provided.