JPH0751971B2 - Bearing device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing device.

[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 considered as a bearing device capable of high-speed rotation and high rigidity of the rotating body.

The applicant has previously provided a permanent magnet attached to a rotating body and a superconductor arranged so as to face the permanent magnet, and the permanent magnet rotates the rotating body. It is provided in the rotating body so that the magnetic flux distribution around the axis does not change due to rotation, the superconductor allows the magnetic flux of the permanent magnet to enter, and at the separated position where the magnetic flux of the permanent magnet enters by a predetermined amount. There is also proposed a superconducting bearing device which is arranged at a position where the distribution of invading magnetic flux does not change due to the rotation of the rotating body (Japanese Patent Application No. 2-2932).
56).

[0004]

However, in the superconducting bearing device as described above, when the rotating body is rotated by the high frequency electric motor, vibration is generated in the rotating body in the axial direction and / or the radial direction, and the vibration thereof is damped. There is a problem of poor performance. As a result, there is a problem that the rotating body cannot be rotated at high speed.

An object of the present invention is to provide a bearing device that solves the above problems.

[0006]

A bearing device according to a first aspect of the present invention is a bearing device provided with a rotating body and a bearing portion for supporting the rotating body in a non-contact state with a fixed portion. A ring-shaped permanent magnet part is concentrically arranged around the circumference of the ring-shaped permanent magnet part, and a ring-shaped magnetic gap in which a magnetic flux oriented in the rotation axis direction of the rotating body exists is formed over the entire circumference of the ring-shaped permanent magnet part.
The bearing device according to the second aspect of the invention, wherein the annular or disc-shaped conductor is concentrically and fixedly provided, and the annular or disc-shaped conductor is movable in the magnetic gap of the permanent magnet portion. Is a bearing device including a rotating body and a bearing portion that supports the rotating body in a non-contact state with respect to a fixed portion. An annular permanent magnet portion is concentrically arranged around the rotating body to form an annular permanent magnet. In the magnet part, an annular magnetic gap in which a magnetic flux oriented in the radial direction of the rotating body exists is formed over the entire circumference, and in the rotating body, a cylindrical conductor parallel to the rotation axis is provided concentrically and fixedly. The cylindrical conductor is adapted to move within the magnetic gap of the permanent magnet section.

A bearing device according to a third aspect of the invention is a bearing device including a rotating body and a bearing portion that supports the rotating body in a non-contact state with respect to a fixed portion. The magnet parts are arranged concentrically at intervals in the circumferential direction, a magnetic gap in which a magnetic flux oriented in the rotation axis direction of the rotating body exists is formed in each permanent magnet part, and the rotating body has an annular or disc shape. The defective conductor is concentrically and fixedly provided, and a large number of conducting wires, which are in the shape of a figure 8 when viewed from the direction of the rotation axis and are insulated from each other at their intersections, are provided on the annular or disc-shaped defective conductor. The lengthwise direction is directed to the radial direction of the rotating body and is attached at intervals in the circumferential direction so that the conducting wire can move within the magnetic gap of the permanent magnet portion.

A bearing device according to a fourth aspect of the present invention is a bearing device including a rotating body and a bearing portion that supports the rotating body in a non-contact state with a fixed portion, and a plurality of permanent magnets are provided around the rotating body. The magnet parts are arranged concentrically at intervals in the circumferential direction, and a magnetic gap in which a magnetic flux oriented in the radial direction of the rotating body exists is formed in each permanent magnet part. The cylindrical defective conductor is concentrically and fixedly provided, and the cylindrical defective conductor is provided with a large number of conductors which are in the shape of a figure 8 when viewed from the radial direction of the rotating body and which are insulated from each other at their intersections.
The lengthwise direction is directed to the direction of the rotation axis of the rotating body and is attached at intervals in the circumferential direction so that the conducting wire can move in the magnetic gap of the permanent magnet portion.

A bearing device according to a fifth aspect of the present invention is a bearing device including a rotating body and a bearing portion that supports the rotating body in a non-contact state with respect to a fixed portion. The magnet parts are arranged concentrically at intervals in the circumferential direction, a magnetic gap in which a magnetic flux oriented in the rotation axis direction of the rotating body exists is formed in each permanent magnet part, and an annular defective conductor is formed in the rotating body. The annular conductor portion is provided concentrically and fixedly, the annular conductor portion is attached to the annular defective conductor, and the annular conductor portion is laminated concentrically so that a plurality of cylindrical conductors parallel to the rotation axis are insulated from each other. It is formed by means of the above, and the conductor portion can move within the magnetic gap of the permanent magnet portion.

A bearing device according to a sixth aspect of the present invention is a bearing device including a rotating body and a bearing portion that supports the rotating body in a non-contact state with a fixed portion, and a plurality of permanent magnets are provided around the rotating body. The magnet parts are arranged concentrically at intervals in the circumferential direction, and a magnetic gap in which a magnetic flux oriented in the radial direction of the rotating body exists is formed in each permanent magnet part. A cylindrical defective conductor is concentrically and fixedly provided, an annular conductor portion is attached to the cylindrical defective conductor, and the annular conductor portion is laminated in the rotation axis direction so that the plurality of annular conductors are insulated from each other. It is formed by being formed so that the conductor portion can move within the magnetic gap of the permanent magnet portion.

The bearing device of the seventh invention comprises an annular permanent magnet portion concentrically and fixedly provided on the rotating body, and an annular superconductor portion arranged so as to face the permanent magnet portion. The annular superconductor part has a plurality of massive superconductors arranged in close proximity to each other. The magnetic flux binding force of at least one superconductor of all the superconductors is smaller than the magnetic flux binding force of the other remaining superconductors.

[0012]

In the bearing device of the first aspect of the invention, when the rotating body moves in the radial direction, the annular or disc-shaped conductor also moves in the radial direction together with the rotating body, but the magnetic flux applied to the conductor changes at this time. Therefore, an eddy current that causes a magnetic flux flows in the conductor in a direction that prevents the change of the magnetic flux. Therefore, an electromagnetic force having a reverse direction is generated in the conductor in proportion to the speed of the movement, and the movement is limited as a viscous force. That is, a braking action occurs.

On the other hand, since the annular permanent magnet portion is formed with the annular magnetic gap over which the magnetic flux oriented in the direction of the rotation axis of the rotating body exists, the annular or disc-shaped conductor rotates together with the rotating body. However, this rotation does not change the magnetic flux. Therefore, it is possible to prevent the braking action on the rotation from occurring.

In the case of the bearing device of the second aspect of the invention, when the rotating body moves in the axial direction, the cylindrical conductor also moves in the axial direction together with the rotating body. Produces a braking force proportional to. Further, similarly to the case of the first aspect, it is possible to prevent the braking action on the rotation from occurring.

In the case of the bearing device according to the third aspect of the present invention, when the rotating body moves in the radial direction, the 8-shaped conductor wire attached to the annular or disc-shaped defective conductor fixedly provided on the rotating body is also generated. It moves in the radial direction together with the rotating body. At this time, the amount of change in the magnetic flux received by the annular portions on both sides of the intersecting portion of the conducting wire is different, so that an electromotive force difference occurs. Therefore, an eddy current that causes a magnetic flux flows in a direction that prevents nonuniformity of the magnetic flux change. Therefore, an electromagnetic force having a reverse direction is generated in the conductive wire in proportion to the speed of the movement, and the movement is limited as a viscous force. That is, a braking action occurs.

On the other hand, the eddy currents flowing in the conductors when the conductors normally rotate coaxially with the rotating body have the same direction in the annular portions on both sides of the intersection, so these currents cancel each other out. Therefore, it is possible to prevent the braking action on the rotation from occurring.

In the case of the bearing device of the fourth invention, when the rotating body moves in the axial direction, the conductive wire also moves in the axial direction together with the rotating body, but like the case of the third invention,
A braking action for the above movement occurs. Further, as in the case of the third invention, it is possible to prevent the braking action on the rotation from occurring.

In the case of the bearing device according to the fifth aspect of the present invention, when the rotating body moves in the radial direction, the annular conductor portion attached to the annular defective conductor fixedly provided on the rotating body also moves in the radial direction together with the rotating body. To do. At this time, the amount of magnetic flux penetrating the cylindrical conductor of the annular conductor portion changes, and an induced electromotive force is generated in the conductor in a direction that hinders the change of magnetic flux. Since the direction of this induced electromotive force is the tangential direction of the conductor, a current flows in the circumferential direction of the conductor, causing Joule loss and generating a braking force. That is, a damping action for vibration in the radial direction occurs.

On the other hand, even when the annular conductor section normally rotates together with the rotating body, the amount of magnetic flux penetrating the cylindrical conductor of the annular conductor section changes, and the induced electromotive force in the conductor prevents the magnetic flux from changing. However, since the induced electromotive force is directed in the radial direction and the conductors are insulated in the radial direction, no current flows in this direction. Therefore, it is possible to prevent the braking force for rotation from being generated.

In the case of the bearing device of the sixth invention, when the rotating body moves in the axial direction, the annular conductor portion also moves in the axial direction together with the rotating body. However, as in the case of the fifth invention, a current is passed through the conductor. It flows to generate a braking force, which has a damping effect on the vibration in the axial direction. Further, as in the case of the fifth aspect, it is possible to prevent the braking force against rotation from being generated.

In the case of the bearing device of the seventh invention, when the rotating body vibrates in the radial direction and / or the axial direction, in the superconductor having a small magnetic flux restraining force, the magnetic flux penetrating into the inside moves in accordance with the vibration. become. On the other hand, in a superconductor having a large magnetic flux restraining force, a force that basically stops the movement of magnetic flux acts. Therefore, a braking action occurs.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. Throughout the drawings, the same parts and parts are designated by the same reference numerals, and description thereof will be omitted.

FIG. 1 shows a first embodiment to which the bearing device of the present invention is applied.
The overall structure of the superconducting bearing device of the embodiment of
2 and 3 are enlarged views of the main part.

The superconducting bearing device is composed of a vertical shaft-shaped rotating body.
(1) is provided. The rotating body (1) is a high-frequency electric motor for driving.
It can be rotated at high speed with (2). Electric motor
(2) is the rotor (3) mounted on the upper end of the rotating body (1)
And a stator (4) arranged around it and attached to a support (not shown).

The rotating body (1) has a horizontal disk-shaped permanent magnet part.
(5) are concentrically provided. The permanent magnet part (5) includes a horizontal disk (6) fixedly provided on the rotating body (1) and made of, for example, copper. An annular groove (7) is formed concentrically with the rotating body (1) on both upper and lower sides of the disk (6), and an annular permanent magnet (8) is formed in each of these groove (7).
Is fitted and fixed. The permanent magnet (8) is a rotating body.
It is provided so that the magnetic flux distribution around the rotation axis of (1) does not change due to rotation.

On both upper and lower sides of the disk (6), annular superconductor portions (9) are arranged so as to face the upper and lower surfaces of the disk (6) at intervals in the direction of the rotation axis. There is. The superconducting part (9) is a perforated horizontal disc (1
0) and the annular part around the hole (10a) of the perforated disc (10),
A plurality of disc-shaped superconductors (11) that are embedded in close proximity to each other at equal intervals in the circumferential direction, facing the permanent magnet (8).
And consists of. The rotating body (1) is passed through the hole (10a) of the perforated disc (10) with a gap.

The disk-shaped superconductor (11) is a yttrium-based high-temperature superconductor, for example, in which a normal conductive particle (Y ₂ Ba ₁ Cu ₁ ) is uniformly mixed inside a substrate made of YBa ₂ Cu ₃ O _x. It has the property of restraining the penetration of the magnetic flux emitted from the permanent magnet (8). The superconductor (2) is arranged at a separated position where the magnetic flux of the permanent magnet (8) penetrates by a predetermined amount and at a position where the distribution of the magnetic flux penetrating does not change due to the rotation of the rotating body (1).

A cooling case (12), which is cooled by a refrigerator or the like via a temperature control unit, is fixed in a housing (not shown) of the superconducting bearing device, and the upper and lower superconductor parts (9) are fixed to the cooling case (12). ) Is fixed. In addition, in FIG. 1, a cooling case (1) for fixing the upper superconductor part (9) is used.
2) is omitted.

When operating the superconducting bearing device, each superconductor (11) is cooled by an appropriate refrigerant circulated in the cooling case (12) and kept in a superconducting state. Therefore, most of the magnetic flux generated from the permanent magnet (8) of the rotating body (1) enters the inside of the superconductor (11) and is restricted (pinning phenomenon). Here, since the superconductor (11) has the normal conductor particles uniformly mixed therein, the distribution of the magnetic flux penetrating inside the superconductor (11) is constant, and therefore, it is as if in the superconductor (11). Rotating body on the virtual pin
The permanent magnet (8) of (1) is now penetrated, and the superconductor (1
The rotating body (1) is restrained together with the permanent magnet (8) with respect to 1). Therefore, the rotating body (1) is supported in the axial direction and the radial direction while floating extremely stably. At this time, the magnetic flux that has entered the superconductor (11) does not become a resistance that impedes rotation as long as the magnetic flux distribution is uniform and unchanged with respect to the rotation axis.

A radial vibration damping device (13) and an axial vibration damping device (14) of the rotating body (1) are provided below the lower case.

Radial vibration damping device for rotating body (1)
(13) includes an annular permanent magnet portion (15) arranged concentrically around the rotating body (1). As shown in FIG. 2, the annular permanent magnet portion (15) has an annular permanent magnet (16) whose upper and lower end portions are magnetized with opposite polarities, and an inner peripheral edge portion which is attached to both upper and lower end surfaces thereof. Rotating body (1) rather than the inner peripheral edge of the magnet (16)
Consisting of a pair of upper and lower annular yokes (17) protruding to the side, a magnetic circuit is formed by the permanent magnet (16) and the upper and lower yokes (17), and the protruding edges of the upper and lower yokes (17) Magnetic gap around the entire circumference
(18) is formed. The permanent magnet (16) has, for example, an N pole at its upper end and an S pole at its lower end, and a downward magnetic flux exists in the magnetic gap (18).

A horizontal disk-shaped conductor (19) is concentrically and fixedly provided on the rotating body (1). The predetermined width of the horizontal disc-shaped conductor (19) near the periphery is the magnetic gap of the permanent magnet (15).
(18) It is designed to be able to move inside.

The axial vibration damping device (14) of the rotating body (1) is provided with an annular permanent magnet portion (21) arranged concentrically around the rotating body (1). As shown in FIG. 3, the annular permanent magnet part (21) has an annular permanent magnet (22) whose both sides in the radial direction are magnetized with opposite polarities, and an upper edge attached to both inner and outer peripheral surfaces thereof. The part consists of a pair of inner and outer annular yokes (23) projecting above the upper edge of the permanent magnet (22), and the permanent magnet (2
A magnetic circuit is formed by 2) and both yokes (23), and a magnetic gap (24) is formed over the entire circumference between the projecting edges of both yokes (23). The permanent magnet (22) has, for example, an N pole on the inner peripheral side and an S pole on the outer peripheral side, and a magnetic flux outward in the radial direction exists in the magnetic gap (24).

A conductor (25) concentrically and fixedly provided on the rotating body (1), which is integrally formed with a cylindrical downward projecting wall (26) having a horizontal disk shape and a peripheral portion parallel to the axial direction. Has been. A predetermined width portion of the cylindrical downward projecting wall (26) of the horizontal disc-shaped conductor (25) is configured to be movable in the magnetic gap (24) of the permanent magnet portion (21).

During operation of this superconducting bearing device, the rotating body
When (1) moves in the radial direction, the horizontal disk-shaped conductor (19) of the vibration damping device (13) also moves in the radial direction together with the rotating body (1). However, at this time, since the magnetic flux applied to the conductor (19) changes, an eddy current that causes the magnetic flux to flow in the conductor (19) in a direction that hinders the change of the magnetic flux.
Therefore, Joule loss proportional to the square of the amplitude of the movement and the speed is generated in the conductor (19), and the braking action is generated. Therefore, the radial vibration of the rotating body (1) is damped.

On the other hand, the rotor (1) is attached to the annular permanent magnet portion (15).
Since the annular magnetic gap (18) in which the magnetic flux oriented in the direction of the axis of rotation of is present is formed over the entire circumference, even if the annular conductor portion (19) rotates with the rotating body (1), this rotation will There is no change in the magnetic flux applied to the conductor (19). Therefore, it is possible to prevent the braking action on the rotation from occurring.

When the rotating body (1) moves in the axial direction, the cylindrical downward projecting wall (26) of the horizontal disc-shaped conductor (25) of the vibration damping device (14) moves in the axial direction together with the rotating body (1). However, the braking action occurs as in the case where the radial movement occurs. Therefore, the vibration of the rotating body (1) in the axial direction is damped. Furthermore, as in the case of the vibration damping device (13) in the radial direction, it is possible to prevent the braking action on the rotation of the rotating body (1) from occurring.

[0038]

[Specific experimental example] The diameter of the horizontal disk (6) of the permanent magnet part (5) is 100 mm, and the rotating body (1) includes the permanent magnet part (5).
Was set to 1 kg. In addition, the horizontal disk-shaped conductor (25) of the axial vibration damping device (14) has a diameter of 50 mm.
mm, thickness 2 mm, cylindrical downward protruding wall (26) thickness 2 m
m, a copper plate having a length of 10 mm in the direction of the axis of rotation was used. Further, as the permanent magnet (22), an outer diameter of 80 mm, an inner diameter of 60 mm, and a surface magnetic flux density of 4000 Gauss are used, and the vertical magnet has a length of 5 mm and a gap (24) has a length of 4 mm. ) Was produced.

The permanent magnet part (5) and the superconductor part (9)
After the relative positioning was performed, the superconductor (11) was cooled and kept in the superconducting state. At this time, the distance Z between the permanent magnet part (5) and the superconductor part (9) was 2 mm. After that, a load of 2 kgf is vertically applied to the rotating body (1) to unload it momentarily, and the relationship between the change in distance between the permanent magnet part (5) and the superconductor part (9) and time is shown. By measuring, the damping performance in the axial direction was examined. The result is shown in FIG. The attenuation coefficient at this time was determined to be 0.25 Ns / mm.

For comparison, the same superconducting bearing device as described above was used except that the vibration damping device in the axial direction was not provided, and the damping performance was examined in the same manner as described above. The result is shown in FIG. Also, when the damping coefficient is calculated, it is 1
It was 0 ⁻³ Ns / mm.

FIG. 6 shows a second embodiment to which the bearing device of the present invention is applied.
The essential parts of the superconducting bearing device of the above embodiment are shown, and FIG. 7 and FIG.

In this embodiment, the radial vibration damping device (30) of the rotating body (1) comprises a plurality of permanent magnets arranged concentrically around the rotating body (1) at circumferential intervals. (3
1) is equipped. Each permanent magnet (31) is C-shaped and has a magnetic gap (32). The surfaces of the permanent magnet (31) that face each other across the magnetic gap (32) have magnetisms of opposite polarities. For example, the upper surface has N-pole magnetism and the lower surface has S-pole magnetism.
There is a downward magnetic flux in (32).

A horizontal disk-shaped defective conductor (33) is concentrically and fixedly provided on the rotating body (1). Disc-shaped defective conductor
In the annular portion near the periphery of (33), a large number of conducting wires (34), which are in the shape of a figure 8 when viewed from above and below and are insulated from each other at their intersections, extend in the longitudinal direction of the rotating body (1). It is buried in the radial direction and at intervals in the circumferential direction.
Then, the conductive wire (34) can move within the magnetic gap (32). At the normal position, the three-dimensional intersection of the conducting wire (34) is located on the straight line connecting the N pole and the S pole of the permanent magnet (31).

The axial vibration damping device (35) for the rotating body (1) comprises a plurality of permanent magnets (36) arranged concentrically around the rotating body (1) at circumferential intervals. ing. Each permanent magnet (36) is C-shaped and has a magnetic gap (37). The surfaces of the permanent magnet (36) that face each other across the magnetic gap (37) have magnetisms of opposite polarities. For example, the inner surface has an N-pole magnetism and the outer surface has an S-pole magnetism, and a magnetic flux inward in the radial direction exists in the magnetic gap (37).

The rotating body (1) is concentrically and fixedly provided with a defective conductor (38) having a horizontal disk shape and a cylindrical downward projecting wall (39) integrally formed at the peripheral edge. Downward protruding wall (39)
In addition, a large number of conducting wires (34), which are in the shape of a figure 8 when viewed in the radial direction of the rotating body (1) and are insulated from each other at their intersections,
However, they are embedded with their length direction oriented vertically and at intervals in the circumferential direction. Then, the conductor wire (34) can move within the magnetic gap (37). At the normal position, the three-dimensional intersection of the lead wire (34) is located on the straight line connecting the N pole and the S pole of the permanent magnet (34).

During operation of this superconducting bearing device, the rotating body
When (1) moves in the radial direction, the horizontal disk-shaped defective conductor (33) of the vibration damping device (30) also moves in the radial direction together with the rotating body (1), so that the 8-shaped conductor (34) also becomes radial. Move in the direction. If this movement is to the right in FIG. 8,
Since the magnetic flux given to the conducting wire (34) changes, the ring portion (34a) on the right side of FIG. 8 of the conducting wire (34) is directed in the direction indicated by the solid arrow A in FIG. 8 so as to prevent the change of the magnetic flux. The eddy current flows, and the eddy current in the direction indicated by the solid arrow B in FIG. 8 flows in the other annular portion (34b). As a result, an electromagnetic force in the direction opposite to the direction of the movement is generated in the conducting wire (34), and a braking action occurs. Therefore, the radial vibration of the rotating body (1) is damped.

On the other hand, when the conducting wire (34) is rotating together with the rotating body (1), for example, in the upper side of FIG. 8, the magnetic flux applied to the conducting wire (34) changes, but this change should be prevented. In addition, an eddy current in the direction indicated by the broken arrow C in FIG. 8 flows in the upper portion of the conductor (34) in FIG. 8, and an eddy current in the direction indicated by the broken arrow D in FIG. 8 flows in the lower portion. However, since these currents cancel each other out, it is possible to prevent the braking action on the rotation from occurring.

When the rotating body (1) moves in the axial direction, the cylindrical downward protruding wall (3) of the horizontal disk-shaped defective conductor (38) is
9) also moves in the axial direction together with the rotating body (1),
As in the case of the radial vibration damping device (30), a braking action occurs, and the axial vibration of the rotating body (1) is damped. Further, as in the case of the vibration damping device in the radial direction, it is possible to prevent the braking action on the rotation from occurring.

[0049]

[Specific experimental example] As a horizontal disk-shaped defective conductor (38) of the axial vibration damper (35), the diameter is 50 mm and the thickness is 2 m.
In this case, a polycarbonate plate having a thickness of 2 mm and a length of 10 mm in the direction of the axis of rotation of the cylindrical downward protruding wall (39) was used. The figure-eight conducting wire (34) is a copper tape wire having a length of 2 mm, a width of 0.5 mm and a thickness of 0.2 mm.
Further, as the permanent magnets (36), those having a cross section of 10 × 10 mm, a surface magnetic flux density of 2000 gauss and a magnetic gap (37) of 4 mm in length were used, and six magnets were arranged at intervals in the circumferential direction.

Then, similarly to the experimental example of the first embodiment, the damping performance in the axial direction was examined. The result is shown in FIG. The damping coefficient at this time was calculated to be 0.
It was 02 Ns / mm.

FIG. 10 schematically shows the structure of a main part of a superconducting bearing device of a third embodiment to which the bearing device of the present invention is applied, and FIG. 11 and FIG.

In this embodiment, the radial vibration damping device (41) of the rotating body (1) is similar to that of the second embodiment.
Permanent magnets (31) with opposing faces that are spaced in the direction of the axis of rotation across the magnetic gap (32) and have opposite polarities, and near the peripheral edge of the horizontal disk-shaped defective conductor (33). An annular conductor portion (42) attached to the annular portion of the. Conductor
The (42) is formed by concentrically stacking a plurality of cylindrical conductors (43) parallel to the rotation axis so as to be insulated from each other. The conductor (42) is a permanent magnet.
It is adapted to move within the magnetic gap (32) of (31).

In the axial vibration damping device (45) of the rotating body (1), as in the second embodiment, the magnetic gaps (37) are sandwiched in the radial direction and the surfaces facing each other are opposite to each other. The permanent magnet (36) having a magnetic polarity of (4) and the annular conductor part (46) attached to the annular portion near the lower edge of the cylindrical downward protruding wall (39) of the horizontal disk-shaped defective conductor (38) It has and. Further, similarly to the second embodiment, the outer surface and the inner surface of the permanent magnets (36) sandwiching the magnetic gaps (37) are magnetized with the same polarity. The conductor portion (46) is formed by vertically stacking a plurality of annular conductors (47) so as to be insulated from each other. The conductor portion (46) can move within the magnetic gap (37) of the permanent magnet (36).

During operation of this superconducting bearing device, the rotating body
When (1) moves in the radial direction, the horizontal disk-shaped defective conductor (33) of the vibration damping device (41) also moves in the radial direction together with the rotating body (1), so the annular conductor part (42) also moves in the radial direction. Moving. At this time, the cylindrical conductor (43) of the annular conductor portion (42)
The amount of magnetic flux penetrating therethrough changes, and an induced electromotive force is generated in the conductor (43) in a direction that prevents the change in magnetic flux. Since the direction of this induced electromotive force is the tangential direction of the conductor (43), a current flows in the circumferential direction of the conductor (43), causing Joule loss and generating a braking force. That is, a damping action occurs against the radial vibration of the rotating body (1).

On the other hand, even when the annular conductor portion (42) normally rotates together with the rotating body (1), the amount of magnetic flux penetrating the cylindrical conductor (43) of the annular conductor portion (42) changes and the conductor ( In 43), an induced electromotive force is generated in the direction that hinders the change of magnetic flux, but the direction of this induced electromotive force is in the radial direction, and the conductors (43) are insulated in the radial direction. Does not flow current. Therefore, it is possible to prevent the braking force for rotation from being generated.

When the rotating body (1) moves in the axial direction, the cylindrical downward projecting wall (3) of the horizontal disk-shaped defective conductor (38) is moved.
9) also moves in the axial direction together with the rotating body (1),
As in the case of the vibration damping device (41) in the radial direction, a braking action occurs and the vibration of the rotating body (1) in the axial direction is damped. Further, as in the case of the vibration damping device in the radial direction, it is possible to prevent the braking action on the rotation from occurring.

[0057]

[Specific experimental example] The horizontal disk-shaped defective conductor (38) of the axial vibration damping device (45) has a diameter of 50 mm and a thickness of 2 m.
In this case, a polycarbonate plate having a thickness of 2 mm and a length of 10 mm in the direction of the axis of rotation of the cylindrical downward protruding wall (39) was used. Further, a 0.5 mm-thick copper annular conductor (47) is laminated with an insulating adhesive to form an annular conductor portion (46), which is attached to the downward protruding wall (39). It was Furthermore, the permanent magnet (36) has a cross section of 10 × 10 m.
m, surface magnetic flux density is 2000 gauss, magnetic gap (37)
6 having a length of 4 mm were used, and 6 pieces were arranged at intervals in the circumferential direction.

Then, the damping performance in the axial direction was examined in the same manner as the experimental example of the first embodiment. The result is shown in FIG. The damping coefficient at this time was calculated to be 0.02 Ns / mm.

FIG. 14 schematically shows the structure of a main part of a superconducting bearing device of a fourth embodiment to which the bearing device of the present invention is applied.

In this embodiment, the annular superconductor portion (9)
Are embedded in the annular portion around the hole (10a) of the perforated disc (10) facing the permanent magnet (8) and adjacent to each other at equal intervals in the circumferential direction. It is equipped with discoid superconductors (50) (51) of various types. Two types of superconductors (50) (51)
Are alternately arranged, for example. One superconductor (50) is
Yttrium-based high temperature superconductor such as YBa ₂ Cu ₃
Consisting O _x in the substrate normal conductor particles _(Y 2 _Ba 1 Cu
₁ ) is uniformly mixed, and the binding force of the magnetic flux penetrating from the permanent magnet (8) is large in the superconducting state. The other superconductor (51) is made of, for example, YBa ₂ Cu ₃
Consisting O _x in the substrate normal conductor particles _(Y 2 _Ba 1 Cu
₁ ) is non-uniformly mixed, and the binding force of the magnetic flux penetrating from the permanent magnet (8) in the superconducting state is small.

For example, when the superconductors (50) and (51) are held in a superconducting state and the permanent magnet (8) is moved closer to or away from the superconductor, the repulsive force between the two is a superconductor having a large magnetic flux binding force.
In the case of (50), it becomes as shown in FIG. 15, and in the case of the superconductor (51) having a small magnetic flux restraining force, it becomes as shown in FIG. The damping coefficient c at this time is represented by the following equation.

C = τP / 2π ² Δz ² = ΔFτ / 2π ² Δz where τ is the period, P is the energy consumption per round trip, z
Indicates a moving distance per round trip, and ΔF indicates an average deviation of repulsive force (see FIGS. 15 and 16).

Therefore, a superconductor having a small magnetic flux restraining force
In the case of (51), the damping coefficient is a superconductor with a large magnetic flux binding force.
It is considered to be larger than (50).

Therefore, the damping coefficient when the rotating body (1) vibrates in the axial direction becomes larger than that when only the superconductor (50) having a large magnetic flux restraining force is used. Similarly, the damping coefficient when the rotating body (1) vibrates in the radial direction also has a large magnetic flux restraining force in the superconductor (50).
It is larger than the case of using only.

[0065]

[Specific Experimental Example] Similar to the experimental example of the first embodiment, the damping performance in the axial direction was examined. The result is shown in FIG.

In the above first to third embodiments, the most effective one is the device of the first embodiment, and the most simple one is the device of the third embodiment. Then, it is preferable to select the device of any one of the first to third embodiments in consideration of the mass of the rotating body and the eccentricity when vibrating.

In the first to third embodiments, the bearing portion that supports the rotating body in a non-contact state is a superconducting bearing composed of a permanent magnet portion and a superconductor portion. However, instead of this, Alternatively, a magnetic bearing using an ordinary electromagnet may be used as the bearing portion.

[0068]

As described above, according to the bearing device of the present invention, the vibration of the rotating body is damped. Therefore, the rotating body can be rotated at high speed.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view schematically showing an overall configuration of a superconducting bearing device according to a first embodiment of the present invention.

FIG. 2 is an enlarged vertical sectional view showing a vibration damping device in a radial direction.

FIG. 3 is an enlarged vertical sectional view showing a vibration damping device in an axial direction.

FIG. 4 is a graph showing the results of a specific experiment conducted using the device of the first embodiment.

FIG. 5 is a graph showing the results of a specific experiment conducted using a conventional device.

FIG. 6 is a perspective view showing a main part of a superconducting bearing device according to a second embodiment of the present invention.

FIG. 7 is an enlarged vertical sectional view showing a vibration damping device in a radial direction.

FIG. 8 is a view taken along the line VIII-VIII in FIG. 7 with a part omitted.

FIG. 9 is a graph showing the results of a specific experiment conducted using the device of the second embodiment.

FIG. 10 is a perspective view showing a main part of a superconducting bearing device according to a third embodiment of the invention.

FIG. 11 is an enlarged vertical sectional view showing a vibration damping device in a radial direction.

FIG. 12 is an enlarged vertical sectional view showing the vibration damping device in the axial direction.

FIG. 13 is a graph showing the results of a specific experiment conducted using the device of the third embodiment.

FIG. 14 is a plan view showing a superconductor section of a superconducting bearing device according to a fourth embodiment of the present invention.

FIG. 15 is a graph showing a relationship between a repulsive force and a distance between a superconductor having a large magnetic flux restraining force, which is held in a superconducting state and a permanent magnet is moved toward and away from the superconductor.

FIG. 16 is a graph showing the relationship between the repulsive force and the distance between a superconductor having a small magnetic flux restraining force, which is held in a superconducting state and a permanent magnet is moved toward and away from the superconductor.

FIG. 17 is a graph showing the results of a specific experiment conducted using the device of the fourth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 rotator 15 annular permanent magnet part 18 magnetic gap 19 horizontal disc conductor 21 annular permanent magnet part 24 magnetic gap 26 downward protruding wall (cylindrical conductor) 31 permanent magnet 32 magnetic gap 33 horizontal disc defective conductor 34 conducting wire 36 Permanent magnet 37 Magnetic gap 39 Lower protruding wall (cylindrical defective conductor) 42 Annular conductor part 43 Annular conductor 46 Annular conductor part 47 Annular conductor 50 Superconductor with large magnetic flux binding force 51 Superconductor with small magnetic flux binding force

Claims (7)

[Claims] 1. A bearing device comprising a rotating body and a bearing portion that supports the rotating body in a non-contact state with a fixed portion,
An annular permanent magnet portion is concentrically arranged around the rotating body, and the annular permanent magnet portion is formed with an annular magnetic gap over which the magnetic flux oriented in the rotation axis direction of the rotating body exists.
A bearing device in which a ring-shaped or disk-shaped conductor is concentrically and fixedly provided on a rotating body so that the ring-shaped or disk-shaped conductor can move within a magnetic gap of a permanent magnet portion. 2. A bearing device comprising a rotating body and a bearing portion that supports the rotating body in a non-contact state with respect to a fixed portion,
An annular permanent magnet section is concentrically arranged around the rotating body, and an annular magnetic gap in which magnetic flux oriented in the radial direction of the rotating body exists is formed over the entire circumference of the annular permanent magnet section. A bearing device in which a cylindrical conductor parallel to the core is concentrically and fixedly provided, and the cylindrical conductor can move within a magnetic gap of the permanent magnet portion. 3. A bearing device comprising a rotating body and a bearing portion that supports the rotating body in a non-contact state with respect to a fixed portion,
A plurality of permanent magnet parts are arranged concentrically around the rotating body at intervals in the circumferential direction, and in each permanent magnet part, a magnetic gap is formed in which a magnetic flux oriented in the rotation axis direction of the rotating body exists. A ring-shaped or disk-shaped defective conductor is concentrically and fixedly provided on the rotating body, and the ring-shaped or disk-shaped defective conductor is shaped like a figure 8 when viewed from the direction of the rotation axis, and is insulated from each other at the intersection thereof. Bearings in which a large number of conducting wires are attached with their length directions oriented in the radial direction of the rotating body and at intervals in the circumferential direction so that the conducting wires can move within the magnetic gap of the permanent magnet portion. apparatus. 4. A bearing device comprising a rotating body and a bearing portion that supports the rotating body in a non-contact state with respect to a fixed portion,
A plurality of permanent magnet parts are concentrically arranged around the rotating body at intervals in the circumferential direction, and a magnetic gap in which a magnetic flux oriented in the radial direction of the rotating body exists is formed in each permanent magnet part. A cylindrical defective conductor parallel to the axis of rotation is concentrically and fixedly provided, and the cylindrical defective conductor is in the shape of a figure 8 when viewed from the radial direction of the rotating body and is insulated from each other at its intersection. A large number of conducting wires are attached with their lengthwise directions facing the direction of the rotation axis of the rotor and at intervals in the circumferential direction so that the conducting wires can move within the magnetic gap of the permanent magnet portion. Bearing device. 5. A bearing device comprising a rotating body and a bearing portion that supports the rotating body in a non-contact state with respect to a fixed portion,
A plurality of permanent magnet parts are arranged concentrically around the rotating body at intervals in the circumferential direction, and in each permanent magnet part, a magnetic gap is formed in which a magnetic flux oriented in the rotation axis direction of the rotating body exists. An annular defective conductor is concentrically and fixedly provided on the rotating body, an annular conductor portion is attached to the annular defective conductor, and the annular conductor portion is insulated from a plurality of cylindrical conductors parallel to the rotation axis. Bearing device formed by being laminated concentrically so that the conductor portion can move within the magnetic gap of the permanent magnet portion. 6. A bearing device comprising a rotating body and a bearing portion for supporting the rotating body in a non-contact state with respect to a fixed portion,
A plurality of permanent magnet parts are concentrically arranged around the rotating body at intervals in the circumferential direction, and a magnetic gap in which a magnetic flux oriented in the radial direction of the rotating body exists is formed in each permanent magnet part. , A cylindrical defective conductor that is parallel to the axis of rotation is concentrically and fixedly provided, an annular conductor portion is attached to the cylindrical defective conductor, and the annular conductor portion is insulated from the plurality of annular conductors. The bearing device is formed by being laminated in the direction of the axis of rotation in such a manner that the conductor portion can move within the magnetic gap of the permanent magnet portion. 7. A ring-shaped superconductor part comprising: a ring-shaped permanent magnet part concentrically and fixedly provided on the rotating body; and a ring-shaped superconductor part arranged so as to face the permanent magnet part. Is provided with a plurality of lumped superconductors arranged close to each other, each lumped superconductor allows the magnetic flux generated by the permanent magnet portion to enter, and can restrain the invading magnetic flux in a superconducting state. A bearing device in which the magnetic flux binding force of at least one of all the superconductors is smaller than the magnetic flux binding force of the other remaining superconductors.