JPH08296648A - Bearing device and its starting method - Google Patents

Abstract

PURPOSE: To support a rotary body of larger weight by improving the load capacity in the axial direction. CONSTITUTION: A bearing device is provided with a vacuum chamber 1 and a rotary body 2 which is rotated around the vertical axis. The vacuum chamber 1 has the downwardly directed surface and the upwardly directed surface, and the rotary body 2 has the upwardly directed surface opposite to the downwardly directed surface of the vacuum chamber 1 and the downwardly directed surface opposite to the upwardly directed surface of the vacuum chamber 1. A control type axial magnetic bearing 9 to energize the rotary body 2 upward by the attraction is provided between the downwardly directed surface of the vacuum chamber 1 and the upwardly directed surface of the rotary body 2. The control type axial magnetic bearing 9 is provided with an electromagnet 16 on the vacuum chamber 1 side and a ferromagnetic body 20 on the rotary body 2 side. A super-conductive bearing 11 to energize the rotary body 2 upwardly by the repulsion is provided between the upwardly directed surface of the vacuum chamber 1 and the downwardly directed surface of the rotary body 2. The super-conductive bearing 11 consists of a vertically movable super-conductive body part 33 on the vacuum chamber 1 side, and a permanent magnet part 32 on the rotary body 2 side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to, for example, a fluid machine or a machine tool requiring high-speed rotation, an electric power storage device for converting surplus electric power into rotational kinetic energy of a flywheel and storing it, or a gyroscope. In particular, a fixed part, a rotating body that rotates about a vertical axis, a bearing means that supports the rotating body in a non-contact manner with respect to the fixed part in the axial direction, and a rotating body in the radial direction with respect to the fixed part. To a bearing device which is supported in a non-contact manner.

[0002]

2. Description of the Related Art Conventionally, as a bearing device of this type, a permanent magnet concentrically and fixedly provided on a rotating body and an end surface of the permanent magnet are opposed to each other with a gap in the direction of the rotation axis of the rotating body. And the permanent magnet is arranged such that the magnetic flux distribution around the rotation axis does not change due to rotation, and the second type superconductor is It is provided with a superconducting bearing arranged in a separated position where the magnetic flux of the permanent magnet penetrates by a predetermined amount, and the magnetic flux of the permanent magnet is pinned to the second-type superconductor between the fixed portion and the rotating body. A superconducting bearing device has been considered which is provided with an initial positioning device for determining the relative position of the fixed part and the rotating body until the rotary operation of the.

This superconducting bearing device is started as follows. That is, at a temperature equal to or higher than the critical temperature of the second type superconductor, the relative position between the fixed portion and the rotating body is determined by the initial positioning device, and thus the magnetic flux of the permanent magnet enters the second type superconductor by a predetermined amount. The second type superconductor is arranged at a separated position and magnetized by the magnetic field of the permanent magnet. Then, the second-type superconductor is cooled to a temperature below the critical temperature and maintained at a temperature at which the second-type superconducting state appears, and the magnetic flux penetrating the second-type superconductor is pinned. Then, eliminating the support of the rotating body by the initial positioning device,
Stabilize by stopping at a position that balances the weight and pinning of the superconducting bearing. In this way, the superconducting bearing device is started.

In this superconducting bearing device, the magnetic flux generated from the permanent magnet is allowed to enter the inside of the superconductor at a temperature higher than the critical temperature, and then the superconductor is cooled to a temperature lower than the critical temperature (magnetic field cooling) and restrained. As a result, the so-called pinning force supports the rotating body 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 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 (gravitational direction). The force (load capacity) has a limit, and there is a problem that it cannot support a heavy rotating body. For example, in a power storage device, it is necessary to increase the size of a flywheel in order to improve power storage efficiency, but in such a case, there is a problem that the weight of the rotating body cannot be supported.

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

[0007]

A bearing device according to a first aspect of the present invention comprises a fixed portion, a rotating body which rotates about a vertical axis, and bearing means which supports the rotating body in a non-contact manner with respect to the fixed portion in the axial direction. And a bearing means for supporting the rotating body in a radial direction in a non-contact manner with respect to the fixed portion, wherein the fixed portion has a downward surface and an upward surface, and the rotating body is provided on the downward surface of the fixed portion. The bearing means, which has an upward facing surface and a downward facing surface facing the upward facing surface of the fixed portion, supports the rotating body in a non-contact axial direction with respect to the fixed portion. Between the control surface and the control type magnetic bearing that is provided between the upper surface of the fixed portion and the lower surface of the rotating body and that moves the rotating body upward by the repulsive force. It is called a bearing that uses magnetic force The control type magnetic bearing includes an electromagnet provided in the fixed portion and a ferromagnetic body provided in the rotating body, and the magnetic force utilizing bearing is provided in the bearing structure body and the rotating body provided in the fixed portion. The bearing structure on the fixed part side is configured to move up and down.

In the above bearing device, a permanent magnet bearing may be provided between the downward surface of the fixed portion and the upward surface of the rotating body to further urge the rotating body upward by a suction force.

The starting method of the bearing device according to the second invention is the first method.
The method for starting the bearing device according to claim 1, wherein the bearing structure on the fixed portion side of the magnetic force utilizing bearing is lowered, and the electromagnet of the control type magnetic bearing is energized to be attracted from the electromagnet of the control type magnetic bearing. Biasing the ferromagnet upwards by force,
The bearing structure on the fixed part side of the bearing utilizing magnetic force is raised, and the bearing structure on the rotor side is biased upward by the repulsive force from this bearing structure, and the rotor is axially driven by the attraction force and repulsive force. It includes non-contact support in the direction.

[0010]

According to the bearing device of the first invention, the magnetic attraction force from the electromagnet in the control type magnetic bearing is applied to the fixed portion by the pinning force during the magnetic field cooling in the superconducting bearing of the conventional superconducting bearing device. On the other hand, the force is larger than the force for supporting the rotating body in the axial direction in a non-contact state. Moreover, part of the weight of the rotating body is supported by the magnetic repulsive force between the two bearing components of the magnetic force bearing. Therefore, the load capacity in the axial direction is improved.

Further, the bearing device of the first invention is started by the starting method of the second invention, whereby the distance between the electromagnet and the ferromagnetic material of the control type magnetic bearing is changed from the electromagnet to the ferromagnetic material. The distance between the two bearing components of the magnetic force-assisted bearing can be increased so that the suction force acting on the bearing can be increased, and the repulsive force acting between the bearing components can be increased. it can. Therefore, the suction force and the repulsion force are effectively used,
As a result, the load capacity in the axial direction is improved.

In the bearing device according to the first aspect of the present invention, if a permanent magnet bearing is provided between the downward surface of the fixed portion and the upward surface of the rotating body to further urge the rotating body upward by a suction force, A part of the weight of the rotating body is also supported by the attraction force of the permanent magnet bearing, so that the load capacity in the axial direction is improved. Further, if a part of the weight of the rotating body is supported by the attraction force of the permanent magnet bearing, the current flowing through the electromagnet of the control type magnetic bearing can be reduced, so that the eddy current loss can be reduced.

[0013]

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

FIG. 1 and FIG. 2 schematically show the whole structure of an electric power storage device to which a bearing device is applied.
FIG. 2 shows the operating state.

1 and 2, a power storage device includes a vacuum chamber (fixed portion) (1) and a vacuum chamber (1).
And a rotating body (2) arranged so as to be able to move and rotate in the axial and radial directions.

The rotating body (2) is made of a non-magnetic material such as aluminum alloy, non-magnetic stainless steel, copper alloy, etc., and is provided on the vertical rotating shaft (3) and the upper end of the rotating shaft (3). It consists of an integrally formed flywheel (4). An annular reinforcing member (5) made of CFRP (composite fiber reinforced plastic) is press-fitted and fixed to the outer periphery of the flywheel (4).

The rotating body (2) can be rotated by a high frequency electric motor (6). The high-frequency motor (6) consists of a rotor (7) mounted on the rotating shaft (3) of the rotating body (2) and a stator mounted on the peripheral wall (1a) of the vacuum chamber (1) around the rotor (7). It consists of (8).

The lower surface (downward surface) of the top wall (1b) of the vacuum chamber (1) and the upper surface (upward surface) of the flywheel (4) of the rotating body (2) face each other, and the bottom wall of the vacuum chamber (1) ( 1c) The upper surface (upward surface) and the rotating shaft (3) lower surface (downward surface) of the rotating body (2) face each other.

Lower surface of top wall (1b) of vacuum chamber (1) and rotating body
A controlled axial magnetic bearing (9) is provided between the flywheel (4) and the upper surface of the flywheel (4), and the lower surface of the top wall (1b) of the vacuum chamber (1) and the flywheel (4) of the rotating body (2) are also provided. ) A permanent magnet bearing (10) that biases the rotating body (2) upward by magnetic attraction is provided between the upper surface and the upper surface.
A superconducting bearing (bearing using magnetic force) (11) is provided between the lower surface of (3) and the upper surface of the bottom wall (1c) of the vacuum chamber (1) to urge the rotating body (2) upward by magnetic repulsive force. , Between the peripheral surface of the rotating shaft (3) of the rotating body (2) and the inner peripheral surface of the peripheral wall (1a) of the vacuum chamber (1), two radial positions of the rotating body (2) orthogonal to each other are set. Two sets of controlled radial magnetic bearings to control
(12) and (13) are provided.

The control type axial magnetic bearing (9) is mounted on the lower surface of the top wall (1b) of the vacuum chamber (1) concentrically with the rotating shaft center (A) and the rotating body (2) in the axial direction (Z). The ring-shaped electromagnet part (14) for controlling the position of the rotating body (2) by suction from the upper side in the (axial direction) and the rotating body so as to face the electromagnet part (14) in the vertical direction. The flywheel (4) of (2) is provided with an annular ferromagnetic body portion (15) provided on the upper surface. The electromagnet section (14) includes an annular electromagnet (16) and an electromagnet.
The yoke member (17) covers the inner peripheral surface, the upper surface, the outer peripheral surface, and the outer peripheral portion of the lower surface of (16). Annular downward projections (17a) are integrally formed on both side edges of the yoke member (17). An annular groove (1) is attached to the upper surface of a disk-shaped rotating member (18) made of a non-magnetic material such as aluminum alloy, non-magnetic stainless steel, or copper alloy fixed to the upper surface of the flywheel (4).
9) is formed concentrically with the rotation axis (A), and the annular ferromagnetic body (20) is fitted and fixed in the annular groove (19) to form the ferromagnetic body portion (15). Has been done. On the upper surface of the ferromagnetic body (20), two annular upper protrusions (20a) are integrally formed so as to face the two lower protrusions (17a) of the yoke member (17). Although not shown, the axial magnetic bearing (9) is equipped with a displacement sensor for detecting the displacement of the rotating body (2) in the Z-axis direction, and the electromagnet (16) and the displacement sensor are not shown in the figure. It is connected to the bearing controller. Then, the magnetic bearing control device controls the current value of the electromagnet (16), that is, the attractive force, based on the output of the displacement sensor, and as a result, the position of the rotating body (2) in the axial direction is controlled. . Axial magnetic bearing
Since (9) and its control device are known, detailed description thereof is omitted.

The permanent magnet bearing (10) comprises a fixed permanent magnet portion (21) provided on the lower surface of the top wall (1b) of the vacuum chamber (1) and an upper surface of the flywheel (4) of the rotating body (2). And a rotating permanent magnet portion (22) provided on the. The fixed permanent magnet part (21) is a horizontal disk (23) made of a non-magnetic material such as aluminum alloy, non-magnetic stainless steel, or copper alloy fixed to the lower surface of the top wall (1b) of the vacuum chamber (1). I have it. A cylindrical hole (24) is formed in the center of the lower surface of the horizontal disc (23), and an annular groove (25) is formed around it to be concentric with the rotation axis (A). The cylindrical fixed permanent magnet (26) is fitted and fixed in the (24), and the annular fixed permanent magnet (27) is fitted and fixed in the annular recessed groove (25). The part (21) is configured. Both fixed permanent magnets (26) (2
In 7), both upper and lower ends have magnetism of opposite polarities, and both ends of the cylindrical fixed permanent magnet (26) and the annular fixed permanent magnet (27) in the vertical direction have opposite polarities. It is tinged. For example, the upper end of the cylindrical fixed permanent magnet (26) has an S-pole magnetism and the lower end has an N-pole magnetism. The annular fixed permanent magnet (27) has an N-pole magnetism at the upper end and an S-pole magnetism at the lower end. Bears. Rotating member fixed on top of flywheel (4)
A cylindrical hole (28) is formed in the center of the upper surface of (18), and an annular groove (29) is formed around the cylindrical hole (28) concentrically with the axis of rotation (A) to form a cylindrical hole (28). While the cylindrical rotary permanent magnet (30) is fitted and fixed in, the annular rotary permanent magnet (31) is fitted and fixed in the annular groove (23),
The rotating permanent magnet section (22) is configured. Each rotating permanent magnet
(30) and (31) are arranged so as to face the fixed permanent magnets (26) and (27). Both of the rotating permanent magnets (30) and (31) have magnets of opposite polarities at the upper and lower ends thereof, respectively, and the upper and lower ends of the cylindrical rotating permanent magnet (30) and the annular rotating permanent magnet (31) in the vertical direction. The part is magnetized with the opposite polarity. In addition, each rotating permanent magnet (30) (31) and each fixed permanent magnet (26) (27)
The opposite ends of the magnetic field have opposite polarities.
For example, the upper end of the cylindrical rotating permanent magnet (30) has an S pole and the lower end has an N pole.
Has an N pole at the upper end and an S pole at the lower end.

The superconducting bearing (11) is the rotating shaft of the rotating body (2).
The vacuum chamber (1) is placed so as to face the permanent magnet portion (rotor side bearing structure) (32) provided on the lower surface of (3) and the permanent magnet portion (32) at a vertical interval. And a superconductor part (fixed part side bearing structure) (33) provided on the upper surface of the bottom wall (1c) of the above so as to be vertically movable. A cylindrical hole (34) is formed at the center of the lower surface of the rotating shaft (3), and an annular groove (35) is formed around the cylindrical hole (35) concentrically with the rotating shaft center (A). 3
The cylindrical permanent magnet (36) is fitted and fixed in the inside of 4), and the annular permanent magnet (37) is fitted and fixed in the inside of the annular groove (35), so that the permanent magnet portion (32) Is configured. Both permanent magnets (36) and (37) are magnetized with opposite polarities at their upper and lower ends, respectively.
The upper and lower ends of the ring-shaped permanent magnet (36) and the ring-shaped permanent magnet (37) are magnetized with opposite polarities. For example, the upper end of the cylindrical permanent magnet (36) has an S-pole magnetism and the lower end has an N-pole magnetism, and the annular permanent magnet (37) has an N-pole magnetism at its upper end and an S-pole magnetism at its lower end. ing. The superconductor part (33) is the bottom wall of the vacuum chamber (1).
Up-down lifting rod of lifting device (38) attached to (1c)
A cooling case (41) fitted in a box-shaped holding member (40), which is fixedly provided at the upper end of (39) and is open upward, via a heat insulating material (not shown) is provided. Cooling case (41)
Is, for example, aluminum alloy, non-magnetic stainless steel,
It is made of non-magnetic material such as copper alloy. An annular superconductor (42) is fixedly arranged in a space inside the cooling case (41). The space inside the cooling case (41) has a flexible cooling fluid supply pipe (4
It is connected to a cooling device (not shown) via 3) and the discharge pipe (44) .By this cooling device, a cooling fluid such as liquid nitrogen is supplied to the supply pipe (43), the space in the cooling case (41) and The superconductor (42) is cooled by being circulated through the discharge pipe (44). Superconductor
(42) is a type 2 superconductor in which a normal conductor (Y ₂ Ba ₁ Cu ₁ ) is uniformly mixed in the bulk of a yttrium-based high temperature superconductor, for example, YBa ₂ Cu ₃ O _7-X . It consists of things. Then, the superconductor (42) is cooled to a temperature below the critical temperature (hereinafter this cooling is referred to as zero magnetic field cooling) after the superconductor (42) is placed in a separated position where the magnetic field of the permanent magnets (36) (37) is not received. Demonstrating diamagnetism.

The radial magnetic bearings (12) and (13) are provided on both upper and lower sides of the high frequency electric motor (6). Although not shown in detail in the radial magnetic bearings (12) and (13), the rotor (2) is attracted from both sides in two radial directions (X-axis and Y-axis directions) orthogonal to each other, It has an electromagnet for controlling the position of the rotating body (2) and a displacement sensor for detecting the displacement of the rotating body (2) in the X-axis and Y-axis directions. It is connected. Then, the magnetic bearing control device controls the current value of the electromagnet, that is, the attractive force, based on the output of the displacement sensor, and as a result, the position of the rotating body (2) in the radial direction is controlled. The radial magnetic bearing (12) (1
Since 3) and its control device are publicly known, detailed description is omitted.

At the inner peripheral surface of the peripheral wall (1a) of the vacuum chamber (1), above the upper radial magnetic bearing (12) and below the lower radial magnetic bearing (13), respectively, a rotating body is provided in an emergency.
Touchdown bearings (45) and (46) are provided, which are rolling bearings that support the upper and lower ends of the rotating shaft (3) of (2).

The power storage device is started up as follows. In the stopped state, as shown in FIG.
The rotating body (2) is supported by upper and lower touchdown bearings (45) (46). Also, the lifting rod (39) of the lifting device (38) is in the lowered position, and the superconductor (42) of the superconducting bearing (11) does not receive the magnetic field of the permanent magnets (36) (37) and its magnetic flux enters. It is separated to a position where it does not happen. At this time, the lower protruding portion (17a) of the yoke member (17) of the electromagnet portion (14) of the axial magnetic bearing (9) and the upper protruding portion (20) of the ferromagnetic body (20) are
The distance in the axial direction with respect to a) is smaller than the distance in the radial direction between the downward protrusions (17a) of the yoke member (17). Then, first, the vacuum chamber (1) is evacuated. Then the electromagnet (16) of the axial magnetic bearing (9)
1 between the yoke member (17) of the electromagnet part (14) of the axial magnetic bearing (9) and the ferromagnetic material (20) of the ferromagnetic material part (14) as shown by the broken line in FIG. Form a magnetic circuit. Then, the ferromagnetic body (20) receives an upward attracting force, which supports a part of the weight of the rotating body (2). At this time, the rotating permanent magnets (30) (31) of the permanent magnet bearing (10) are fixed permanent magnets.
(26) An upward suction force is received from (27), which also supports a part of the weight of the rotating body (2). The sum of the upward attractive force that the ferromagnetic body (20) receives and the upward attractive force that the rotating permanent magnets (30) (31) receive is smaller than the weight of the rotating body (2), for example, 50% of the total weight. %. Therefore,
Rotating body (2) Yes, it has not yet floated and does not come into contact with it in the axial direction. Then, using a cooling device, the superconducting bearing
A cooling fluid is circulated in the cooling case (41) of (11) to cool the superconductor (42) to a temperature equal to or lower than the critical temperature to bring it into a superconducting state, and maintain this state. That is, a diamagnetic state appears in the superconductor (42). Then, the elevating rod (39) of the elevating device (38) is raised to raise the superconductor portion (33) to approach the permanent magnet portion (32). Then, due to the magnetic repulsive force generated between the permanent magnets (36) (37) and the superconductor (42),
The remaining weight of (2) will be supported and the rotating body (2)
Emerges. As a result, the gap between the lower protrusion (17a) of the yoke member (17) of the axial magnetic bearing (9) and the upper protrusion (20a) of the ferromagnetic body (20) becomes smaller, and the ferromagnetic body (20) becomes The upward suction force received is increased. Moreover, permanent magnet bearings
The distance between the fixed permanent magnets (26) (27) and the rotating permanent magnets (30) (31) in (10) also becomes smaller, and the rotating permanent magnets (30) (31) move from the fixed permanent magnets (26) (27). The upward suction force received is also increased.
Therefore, the rotating body (2) is non-contact supported in the axial direction in an extremely stable state. Then, the upper and lower radial magnetic bearings (12) and (13) perform initial positioning in the radial direction of the rotating body (2). As a result, FIG.
As shown in, the rotating body (2) is attached to the axial magnetic bearing (9).
That is, they are non-contact supported by the permanent magnet bearing (10), the superconducting bearing (11) and the radial magnetic bearings (12) and (13). When the rotating body (2) is supported in a non-contact manner, the high frequency electric motor (6) is operated to rotate the rotating body (2). And
While the rotating body (2) is rotating, electric energy is converted into rotational kinetic energy and stored in the flywheel (4). While the rotor (2) is rotating, the axial magnetic bearing (9) and radial magnetic bearings (12) (13) position control function causes axial and radial runout of the rotor (2). Is prevented.

If a power failure occurs while the rotating body (2) is rotating, the high-frequency motor (6) stops, but the flywheel (4) causes the rotating body (2) to decelerate slightly but continue. And then rotated. As a result, the high frequency motor
(6) operates as a generator, and the rotational kinetic energy stored in the flywheel (4) is taken out as electric energy and stored in a storage battery (not shown). The electric power stored in the storage battery is sent to an external power consumer goods and a cooling device for the superconducting bearing (11) not shown, and the power consumer goods and the superconducting bearing (11) continue to operate. A part of the electric power stored in the storage battery is sent to the magnetic bearing control device of the axial magnetic bearing (9) and the radial magnetic bearing (12) (13), which causes these magnetic bearings (9) (12) (13). The position control function of is activated. Then, until the rotating kinetic energy stored in the flywheel (4) decreases and the rotating body (2) stops, the rotating body (2) keeps the axial magnetic bearing (9) and the permanent magnet bearing (10). , Superconducting bearings (11) and radial magnetic bearings (12)
Non-contact supported by (13). In addition, the position control function of the axial magnetic bearing (9) and the radial magnetic bearings (12) and (13) prevents the rotor (2) from swinging in the axial direction and the radial direction.

In the above embodiment, the axial magnetic bearing (9) and the radial magnetic bearings (12) and (13) are magnetic bearings each having a displacement sensor. Instead of this, a known sensorless magnetic bearing is used. It can also be used. In this case, it is possible to prevent a decrease in safety due to a failure of the sensor circuit.

In the above embodiment, the rotating body (2)
Is rotated by a high frequency electric motor (6). Instead of this, at least one set of radial magnetic bearings (12) (13) is provided in addition to the position control function of the rotating body (2). It may have an electric drive function for rotationally driving the rotating body (2). In this case, the high frequency motor (6) becomes unnecessary.

In the above embodiment, the coil of the electromagnet (16) of the axial magnetic bearing (9) may be made of a superconducting wire. In this case, the upward attraction force exerted on the ferromagnetic body (20) is further increased.

In the above embodiment, the superconductor (42) is cooled with zero magnetic field at the time of starting the power storage device. Instead of this, the magnetic fields of the permanent magnets (36) (37) are used. Then, the superconductor (42) may be magnetically cooled. In this case, the permanent magnet (36) (3
7) is urged upward. However, when magnetically cooling the superconductor (42), it is necessary to perform initial radial positioning of the rotating body (2) by the radial magnetic bearings (12) and (13) in advance.

Further, in the above embodiment, the superconducting bearing
As the superconductor of (11), a type 1 superconductor showing complete diamagnetism made of mercury, lead or the like may be used. In this case, the permanent magnet is biased upward by the superconductor due to the magnetic repulsive force due to the Meissner effect of the superconductor of the superconducting bearing.

3 to 6 show the bottom wall (1) of the vacuum chamber (1).
c) Part of the modified example of the magnetic force utilizing bearing, which is provided between the upper surface and the lower surface of the rotating shaft (3) of the rotating body (2) and supports the rotating body (2) upward by the repulsive force, is omitted. Is shown schematically. 3 to 6, the same components as those shown in FIGS. 1 and 2 are designated by the same reference numerals. Further, the same components are denoted by the same reference numerals throughout FIGS. 3 to 6.

In FIG. 3, a superconducting bearing (bearing using magnetic force) (50) is fitted in a cylindrical hole (51) formed at the center of the lower surface of the rotating shaft (3) of the rotating body (2). It is provided with a fixed columnar permanent magnet (rotor side bearing structure) (52).
The upper and lower ends of the permanent magnet (52) are magnetized with opposite polarities, for example, the upper end has an S pole and the lower end has an N pole. In addition, the superconducting bearing (50) is a permanent magnet disposed below the superconducting portion (33) so as to face the permanent magnet (52).
It is equipped with (53). The superconductor part (33) and the permanent magnet (53)
It can be moved up and down together. Superconductor part
The permanent magnet (53) on the lower side of (33) is the permanent magnet on the side of the rotating body (2).
It is arranged so as to substantially face (52). Superconductor part
The upper and lower ends of the lower permanent magnet (53) of the (33) have opposite polarities, and the opposite end of the permanent magnet (52) is the permanent magnet (52). It is magnetized with the same polarity as. For example, the upper end of the permanent magnet (53) has an N pole magnetism and the lower end has an S pole magnetism.

When such a superconducting bearing (50) is provided, the diamagnetism that appears in the superconductor (42) causes permanent magnets (5
The lower side of the superconductor part (33) acting on the permanent magnet (52) when supporting a part of the weight of the rotating body (2) by the magnetic repulsive force generated between the 2) and the superconductor (42). Part of the weight of the rotating body (2) can be supported by the magnetic repulsive force of the permanent magnet (53).
Therefore, the load capacity in the axial direction is improved, and the heavier rotating body (2) can be supported.

In FIG. 4, a superconducting bearing (bearing using magnetic force) (55) is provided with an electromagnet (56) arranged below the superconductor portion (33) so as to face the permanent magnet (52). . The superconductor part (33) and the electromagnet (56) can be moved up and down together. The electromagnet (56) is arranged so as to substantially face the permanent magnet (52) on the rotating body (2) side. Electromagnet (5
The upper and lower ends of 6) are magnetized with opposite polarities, and the ends facing the permanent magnet (52) are magnetized with the same polarity as the permanent magnet (52). For example, the electromagnet (5
The upper end of 6) has a south pole and the lower end has a north pole.

When such a superconducting bearing (55) is provided, diamagnetism that appears in the superconductor (42) causes permanent magnets (5
The magnetic repulsive force generated between the 2) and the superconductor (42) supports a part of the weight of the rotating body (2) by the magnetic repulsive force of the electromagnet (56) acting on the permanent magnet (52). Rotating body (2)
Can support a part of the weight. Therefore, the load capacity in the axial direction is improved, and the heavier rotating body (2) can be supported.

In FIG. 4, the coil of the electromagnet (56) may be made of a superconducting wire. In this case, the magnetic repulsion force of the electromagnet (56) acting on the permanent magnet (52) is further increased.

In FIG. 5, a permanent magnet bearing (bearing using magnetic force) (60) is a permanent magnet (fixed part side bearing structure) (upper movable part) which is vertically movable on the bottom wall (1c) of the vacuum chamber (1). 61). This permanent magnet (61) is a permanent magnet on the rotating body (2) side.
It is arranged so as to substantially face (52). The upper and lower ends of the vertically movable permanent magnet (61) are magnetized with opposite polarities, and the end facing the permanent magnet (52) on the rotating body (2) side has the same polarity as the permanent magnet (52). Is magnetized. For example,
The upper end of the permanent magnet (61) has a north pole and the lower end has a south pole.

When such a permanent magnet bearing (60) is provided, a part of the weight of the rotating body (2) is caused by the magnetic repulsive force generated between the permanent magnets (52) (61) and the permanent magnet. Is supported.

In FIG. 6, a magnetic force utilizing bearing (65) includes an electromagnet (fixed part side bearing structure) (66) which is vertically movable in the bottom wall (1c) of the vacuum chamber (1), and an electromagnet ( The electromagnet (66) and a permanent magnet (67) arranged so as to move up and down together with the electromagnet (66) are provided below the 66). Electromagnets (66) and permanent magnets (67)
Are arranged so as to substantially face the permanent magnet (52) on the rotating body (2) side. The upper and lower ends of the electromagnet (66) are magnetized with opposite polarities, and the end facing the permanent magnet (52) on the rotating body (2) side has the same polarity magnetism as the permanent magnet (52). It is designed to take on. For example, the upper end of the electromagnet (66) is magnetized as an N pole and the lower end is magnetized as an S pole. The upper and lower ends of the permanent magnet (67) below the electromagnet (66) are magnetized with opposite polarities, and the end facing the permanent magnet (52) on the rotating body (2) side has this permanent magnet. It has the same polarity as the magnet (52). For example, the upper end of the permanent magnet (67) has a north pole and the lower end has a south pole.

When the bearing (65) utilizing such magnetic force is provided, due to the magnetic repulsive force generated between the electromagnet (66) and the permanent magnet (52) on the rotor (2) side, the rotor (2) The magnetic repulsive force of the electromagnet (66) is increased by the permanent magnet (67) below the electromagnet (66) while supporting a part of its weight. Therefore, the load capacity in the axial direction is improved, and the heavier rotating body (2) can be supported.

In FIG. 6, the coil of the electromagnet (66) may be made of a superconducting wire. In this case, the magnetic repulsion force of the electromagnet (66) acting on the permanent magnet (52) is further increased.

[0043]

As described above, according to the bearing device and the method of starting the same of the present invention, the load capacity in the axial direction is improved. Therefore, it becomes possible to support a heavier rotating body. As a result, for example, when applied to a power storage device, it becomes possible to support a rotating body having a large flywheel, and power storage efficiency is improved.

In the bearing device of the present invention, if a permanent magnet bearing is provided between the downward surface of the fixed portion and the upward surface of the rotating body to further urge the rotating body upward by a suction force, this permanent magnet bearing is provided. Part of the weight of the rotating body is also supported by the attractive force of the magnet bearings, so that the load capacity in the axial direction is improved. Further, if a part of the weight of the rotating body is supported by the attraction force of the permanent magnet bearing, the current flowing through the electromagnet of the control type magnetic bearing can be reduced, so that the eddy current loss can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic vertical cross-sectional view of a power storage device in a stopped state to which a bearing device according to an embodiment of the present invention is applied.

FIG. 2 is a schematic vertical cross-sectional view of a power storage device in an operating state to which the bearing device according to the embodiment of the present invention is applied.

FIG. 3 is a partially enlarged cross-sectional view schematically showing a first modification of the magnetic force utilizing bearing, with a part thereof omitted.

FIG. 4 is a partially enlarged cross-sectional view schematically showing a second modification of the magnetic force utilizing bearing, with a part thereof omitted.

FIG. 5 is a partially enlarged cross-sectional view schematically showing a third modification of the magnetic force utilizing bearing, with a part omitted.

FIG. 6 is a partially enlarged sectional view schematically showing a fourth modification of the magnetic force utilizing bearing, with a part omitted.

[Explanation of symbols]

 (1) Vacuum chamber (fixed part) (2) Rotating body (9) Controlled axial magnetic bearing (11) Superconducting bearing (bearing using magnetic force) (12) Controlled radial magnetic bearing (13) Controlled radial magnetic bearing (16) ) Electromagnet (20) Ferromagnetic material (32) Permanent magnet part (rotor side bearing structure) (33) Superconductor part (fixed part side bearing structure) (50) Superconducting bearing (magnetic force bearing) (52) Permanent magnet (Rotor side bearing structure) (55) Superconducting bearing (Magnetic force bearing) (60) Permanent magnet bearing (Magnetic force bearing) (61) Permanent magnet (Fixed side bearing structure) (65) Magnetic force bearing (66) Electromagnet (fixed part side bearing structure)

Claims (3)

[Claims] 1. A fixed part, a rotating body that rotates about a vertical axis, a bearing means that supports the rotating body in a non-contact manner with respect to the fixed part in the axial direction, and a rotating body in the radial direction with respect to the fixed part. A bearing device having contact means for supporting in a non-contact manner, wherein the fixed portion has a downward surface and an upward surface, and the rotating body faces an upward surface facing the downward surface of the fixed portion and an upward surface of the fixed portion. Bearing means for supporting the rotating body in the axial direction in a non-contact manner with respect to the fixed portion is provided between the downward surface of the fixed portion and the upward surface of the rotating body, and the rotating body is attracted by a suction force. Control type magnetic bearing for urging the rotor upward, and a magnetic-force-bearing bearing provided between the upper surface of the fixed portion and the lower surface of the rotor and biasing the rotor upward by repulsive force. Magnetic bearing installed on the fixed part And a ferromagnetic body provided on the rotating body, wherein the magnetic force utilizing bearing is composed of a bearing structure body provided on the fixed portion and a bearing structure body provided on the rotating body, and A bearing device in which the bearing structure moves up and down. 2. The bearing device according to claim 1, further comprising a permanent magnet bearing provided between the downward surface of the fixed portion and the upward surface of the rotating body to urge the rotating body upward by a suction force. 3. The method for starting the bearing device according to claim 1, wherein the bearing structure on the fixed portion side of the magnetic force utilizing bearing is lowered, and the electromagnet of the control type magnetic bearing is energized to control type. The ferromagnetic body is biased upward by the attraction force from the electromagnet of the magnetic bearing, the bearing structure on the fixed side of the bearing utilizing magnetic force is raised, and the repulsive force from this bearing structure causes the bearing structure on the rotating body side. A starting method of the bearing device, comprising: urging the rotor upward, and supporting the rotating body in the axial direction in a non-contact manner by the suction force and the repulsive force.