Damper for rotating machine and rotating machine provided with same

Abstract

A damper (18) for a rotating machine is provided with: an inner member (30) capable of supporting a bearing (16) for rotatably supporting a shaft (12) of the rotating machine; an outer member (40) provided on the outer peripheral side of the inner member (30); and a magnet (50). One of the inner member (30) and the outer member (40) is a conductive member, and the magnet (50) is fixed to the other of the inner member (30) and the outer member (40) and faces the one of the inner member (30) and the outer member (40) with a gap therebetween.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on Japanese Patent Application No. 2022-149533 filed on September 20, 2022 and Japanese Patent Application No. 2023-43537 filed on March 17, 2023, and claims the benefits of these priorities, the entire contents of these patent applications are incorporated into this specification by reference. Technical Field

[0003] The present disclosure relates to a rotary machine damper and a rotary machine provided with the rotary machine damper (ROTARY MACHINE DAMPER, AND ROTARY MACHINE PROVIDED WITH SAME). Background Art

[0004] As a technique for suppressing vibration of a rotating shaft of a rotating machine, a friction type damper such as a metal mesh damper is known (for example, Patent Document 1).

[0005] (Prior art literature)

[0006] (Patent Document)

[0007] Patent Document 1: Japanese Patent Application Publication No. 2020-159434 Summary of the invention

[0008] (Problems to be solved by the invention)

[0009] Since the friction type damper generates a damping force due to the friction between the components, these components are easily worn and thus have a relatively short life.

[0010] The present disclosure has been made in view of such a problem, and an object of the present disclosure is to provide a technology capable of extending the life of a rotary machine damper.

[0011] (Measures taken to solve the problem)

[0012] In order to solve the above-mentioned problems, a damper for a rotating machine in a certain aspect of the present disclosure includes: an inner member capable of supporting a bearing for supporting a shaft of a rotating machine in a rotatable manner; an outer member disposed on the outer peripheral side of the inner member; and a magnet. One of the inner member and the outer member is a conductive member, the magnet is fixed to the other of the inner member and the outer member, and is opposed to one of the inner member and the outer member with a gap therebetween, the inner member is capable of displacement in the axial direction and radial direction of the shaft, and the axial and radial vibrations of the shaft are attenuated by the electromagnetic induced electromotive force based on the displacement of the inner member.

[0013] Another aspect of the present disclosure is a rotating machine including: the above-mentioned damper for a rotating machine; a bearing supported by an inner member of the damper for a rotating machine; and a rotating shaft rotatably supported by the bearing.

[0014] (Effects of the Invention)

[0015] According to the present disclosure, it is possible to extend the life of the rotating machine damper. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a cross-sectional view of the rotating machine according to the embodiment.

[0017] Figure 2 It is enlarged to show Figure 1 An enlarged cross-sectional view of the rotating support portion and its surroundings.

[0018] Figure 3 yes Figure 2 A three-dimensional cross-sectional view of a damper for a rotating machine.

[0019] Figure 4 It is a figure which shows the simulation result.

[0020] Figure 5 It is a figure which shows the simulation result.

[0021] Figure 6 This is an enlarged cross-sectional view showing an enlarged view of a rotation support portion and its periphery of a rotating machine according to a first modified example.

[0022] Figure 7 This is an enlarged cross-sectional view showing an enlarged view of a rotation support portion and its periphery of a rotating machine according to a second modified example.

[0023] Figure 8 It is a figure which shows the simulation result.

[0024] Fig. 9 It is a figure which shows the simulation result.

[0025] Fig.10 It is a figure which shows the simulation result.

[0026] Fig.11 It is a figure which shows the simulation result.

[0027] Fig.12 This is an enlarged cross-sectional view showing an enlarged view of a rotation support portion and its periphery of a rotating machine according to a third modified example.

[0028] Fig.13 It is an enlarged cross-sectional view showing an enlarged view of a rotation support portion and its periphery of a rotating machine according to a fourth modified example.

[0029] Fig.14It is an enlarged cross-sectional view showing an enlarged view of a rotation support portion and its periphery of a rotating machine according to a fifth modified example.

[0030] Fig.15 It is an enlarged cross-sectional view showing an enlarged view of a rotation support portion and its periphery of a rotating machine according to a sixth modification.

[0031] Fig.16 It is a figure which shows the simulation result.

[0032] Fig.17 It is an enlarged cross-sectional view showing an enlarged view of a rotation support portion and its periphery of a rotating machine according to a seventh modification.

[0033] Fig.18 It is an enlarged cross-sectional view showing an enlarged view of a rotation support portion and its periphery of a rotating machine according to an eighth modification.

[0034] Fig.19 It is a figure which shows the simulation result.

[0035] Fig. 20 It is a figure which shows the simulation result. DETAILED DESCRIPTION

[0036] Figure 1 This is a cross-sectional view of the rotating machine 10 according to the embodiment cut along a plane including the rotation axis R which is the rotation center of the shaft 12 . Figure 2 It is enlarged to show Figure 1 FIG. 2 is an enlarged cross-sectional view of one of the two rotation support parts 14 and its surroundings. Figure 3 yes Figure 2 The rotary machine 10 is a three-dimensional cross-sectional view of a rotary machine damper 18. The rotary machine 10 is, for example, a liquid hydrogen pump or a liquefied methane pump of a rocket engine, or an ultra-high pressure liquid hydrogen and booster pump of a hydrogen station. That is, the rotary machine 10 may be a rotary machine used in an extremely low temperature environment. Here, "extremely low temperature" refers to a temperature below -253°C, for example.

[0037] The rotating machine 10 includes a shaft 12 that rotates about a rotation axis R and two rotation support parts 14 that rotatably support the shaft 12. The number of rotation support parts 14 provided in the rotating machine 10 is not particularly limited, and the shaft 12 is supported by a plurality of rotation support parts 14 that are arranged at different positions in the axial direction (a direction parallel to the rotation axis R of the shaft 12), thereby supporting the shaft 12 more stably.

[0038] The rotation support portion 14 includes two bearings 16 for rotatably supporting the shaft 12 and a rotary machine damper 18 for suppressing vibration of the two bearings 16 and the shaft 12. The number of bearings 16 included in the rotation support portion 14 is not particularly limited.

[0039] The shaft 12 is rotatably supported by the bearing 16 .

[0040] The bearing 16 is not particularly limited, and is typically a rolling bearing. The bearing 16 includes an inner ring 20, an outer ring 22, and a plurality of rolling elements 24. The inner ring 20 surrounds the shaft 12 and is fixed to the shaft 12. That is, the inner ring 20 is structurally integrated with the shaft 12 and rotates integrally with the shaft 12. In addition, when the rotating machine 10 is a liquid hydrogen pump for a rocket engine or an ultra-high pressure liquid hydrogen booster pump for a hydrogen station, the shaft 12 and the inner ring 20 rotate at tens of thousands of revolutions per minute (rpm). There is no particular limitation on the method of fixing the inner ring 20 to the shaft 12. The bearing 16 is supported by a damper 18 for a rotating machine.

[0041] As described above, the rotating machine 10 can be a rotating machine used in an extremely low temperature environment. Therefore, the rotating machine damper 18 is configured to be able to be used in an extremely low temperature environment. Here, "capable of being used in an extremely low temperature environment" means that when used in an extremely low temperature environment, a damping force that is the same as or greater than that when used in a normal temperature environment is obtained. Here, the viscosity of the viscous body of a viscous damper such as an oil damper decreases in an extremely low temperature environment, so the damping force decreases. Therefore, the viscous damper cannot be used in an extremely low temperature environment. In contrast, the rotating machine damper 18 of the present embodiment is configured as a non-viscous damper. In detail, the rotating machine damper 18 is configured as a so-called magnetic damper (eddy current damper) that does not have the limitations of a viscous damper, that is, it can be used in an extremely low temperature environment.

[0042] The rotating machine damper 18 includes an inner member 30 for supporting the bearing 16 , an outer member 40 provided on the outer peripheral side of the inner member 30 , and two magnets 50 provided between the inner member 30 and the outer member 40 .

[0043] The inner member 30 includes: a bearing support portion 32 for supporting the bearing 16 and two opposing portions 34 facing the magnetic pole faces of the magnet 50 respectively. The bearing support portion 32 is formed in a cylindrical shape, for example, a cylindrical shape. In addition, the bearing support portion 32 is not limited to a cylindrical shape. The bearing support portion 32 can also be formed, for example, in a C-shaped cross section orthogonal to the axial direction. In addition, for example, the bearing support portion 32 can also be a stacked body formed by overlapping a plurality of C-shaped components in a manner in which the circumferential positions of the cutouts are different from each other. The bearing support portion 32 surrounds the outer rings 22 of the two bearings 16 and is fixed to the outer rings 22. That is, the bearing support portion 32 is structurally integrated with the outer ring 22, and moves (displaces) integrally with the outer ring 22, for example, in the axial or radial direction. The inner member 30 does not specifically limit the method of fixing the two bearings 16. In addition, since the bearing 16 is interposed between the inner member 30 and the shaft 12, the inner member 30 does not rotate with the rotation of the shaft 12.

[0044] In the present embodiment, the two opposing portions 34 protrude radially outward from the bearing support portion 32. The two opposing portions 34 are separated from each other in the axial direction. In the present embodiment, the opposing portions 34 are formed to be continuous in the circumferential direction, that is, to be formed in an annular shape. In addition, the opposing portions 34 may also be formed at intervals in the circumferential direction. In the present embodiment, the opposing portions 34 and the magnet 50 are axially opposed with a predetermined gap therebetween.

[0045] The bearing support portion 32 and the facing portion 34 may be formed integrally, or may be formed independently and then joined together.

[0046] The inner member 30 is a conductive member. In addition, the inner member 30 is preferably a non-magnetic body. In this case, the magnetic attraction force between the inner member 30 and the magnet 50 is avoided. Specifically, the inner member 30 is preferably a non-magnetic body having a higher electrical conductivity in an extremely low temperature environment than in a normal temperature environment, such as aluminum.

[0047] In addition, as a modified example, the bearing support portion 32 may not have conductivity (ie, may be non-conductive). That is, the inner member 30 only needs to have conductivity at least in the facing portion 34 .

[0048] The outer member 40 is fixed to a component (not shown) of the rotating machine 10. The outer member 40 includes an outer peripheral portion 42 surrounding the inner member 30, two annular cover portions 44 extending radially inward from both ends of the outer peripheral portion 42 in the axial direction, and a magnet support portion 46 for supporting the magnet 50.

[0049] The outer peripheral portion 42 is formed in a tubular shape, for example, a cylindrical shape. In addition, the outer peripheral portion 42 is not limited to a tubular shape. The outer peripheral portion 42 may be formed, for example, in a C-shaped cross section orthogonal to the axial direction. In addition, for example, the outer peripheral portion 42 may also be a laminated body formed by overlapping a plurality of C-shaped components in a manner in which the circumferential positions of the cutouts are different from each other.

[0050] In this embodiment, the magnet support portion 46 protrudes radially inward from the axial center of the outer peripheral portion 42. The magnet support portion 46 may be formed to be continuous in the circumferential direction, that is, to be formed in an annular shape, or may be formed to be spaced apart in the circumferential direction. Magnets 50 are fixed to both end surfaces 46a and 46b of the magnet support portion 46 in the axial direction, respectively.

[0051] The cover portion 44 faces the magnet 50 via the facing portion 34 in the axial direction.

[0052] The magnet 50 is a permanent magnet. The magnet 50 is magnetized in such a manner that the two ends in the axial direction become different magnetic poles. In detail, in the magnet 50, the N pole as one magnetic pole face abuts against the axial end faces 46a, 46b of the magnet support portion 46, and the S pole as the other magnetic pole face is axially opposed to the opposing portion 34 with a predetermined gap therebetween. In addition, the N pole and the S pole of the magnet 50 may also be opposite. The magnet 50 is formed in a circumferentially continuous ring shape. In addition, the magnet 50 may also be formed at intervals in the circumferential direction.

[0053] The outer component 40 is a magnetic body formed of a specified magnetic material. The outer component 40 is preferably a soft magnetic body formed of a material with high magnetic permeability, that is, a soft magnetic material. Here, as described above, the magnet support portion 46 of the outer component 40 is opposite (contacted) to the N pole of the magnet 50, and the cover portion 44 is opposite to the S pole of the magnet 50. Therefore, the magnetic flux emitted from the N pole of the magnet 50 passes through the magnet support portion 46, the outer peripheral portion 42, and the cover portion 44 in sequence, and passes through (through) the opposing portion 34 in the axial direction and returns to the S pole. That is, the outer component 40 functions as a yoke that constitutes a part of the magnetic circuit. As a result, the cancellation of magnetic flux is suppressed, and in addition, the leakage magnetic flux is reduced, and the magnetic efficiency is improved.

[0054] The magnet 50, the magnet support portion 46, the outer peripheral portion 42, and the cover portion 44 constitute a magnetic circuit M. The magnetic flux of the magnetic circuit M penetrates the opposing portion 34 in the axial direction. The magnetic circuit M provides the opposing portion 34 with a magnetic flux density distribution that changes according to the displacement of the opposing portion 34 accompanying the vibration of the shaft 12. Specifically, the magnetic circuit M provides the opposing portion 34 with a magnetic flux density distribution that is non-uniform in the radial direction. This can be achieved, for example, by making the magnetic flux density of the magnet 50 non-uniform in the radial direction. The magnetic flux density in the opposing portion 34 is non-uniform in the radial direction, and thus, when the opposing portion 34 is displaced in the radial direction due to the vibration of the shaft 12, the magnetic flux penetrating the opposing portion 34 in the axial direction changes. With respect to the axial direction, the magnetic flux density in the opposing portion 34 changes according to the distance between the magnet 50 and the opposing portion 34. Therefore, when the opposing portion 34 is displaced in the axial direction due to the vibration of the shaft 12, the magnetic flux penetrating the opposing portion 34 in the axial direction changes.

[0055] The above is the structure of the rotating machine 10 including the rotating machine damper 18. Next, its operation will be described.

[0056] If the shaft 12 vibrates, that is, moves (displaces) in the axial or radial direction, the vibration bearing 16 and even the inner part 30 move in the axial or radial direction. Therefore, if the shaft 12 vibrates, the opposing part 34 of the inner part 30 moves in the axial or radial direction relative to the magnet 50. At this time, the magnetic flux that passes through the opposing part 34 in the axial direction changes, and an induced electromotive force caused by electromagnetic induction is generated in the opposing part 34, and an eddy current flows. The eddy current and the magnetic flux (magnetic field) of the magnet 50 act, and a resistance in the opposite direction to the relative displacement direction of the inner part 30 and the magnet 50 acts between the opposing part 34, that is, the inner part 30 and the magnet 50. This resistance is proportional to the relative speed between the inner part 30 and the magnet 50, and therefore acts as a damping force. This damping force attenuates the vibration of the shaft 12.

[0057] Next, the present inventors conducted a simulation under the following conditions in order to confirm the damping performance of the rotating machine damper 18 according to the present embodiment.

[0058] Inner diameter of the bearing support portion 32 of the inner member 30: 148 mm

[0059] ·Outer diameter of the outer peripheral portion 42 of the outer member 40: 264 mm

[0060] Axial gap between the facing portion 34 and the magnet 50: 0.5 mm

[0061] Under such conditions, the shaft 12 is subjected to radial or axial pulse excitation.

[0062] Figure 4It is a diagram showing the damped vibration waveform (simulation result) when the shaft 12 is pulse-excited in the radial direction. The horizontal axis is time (ms), and the vertical axis is the amplitude (m) of the shaft 12. Curve 70 represents the damped vibration waveform of the present embodiment. Curves 72, 74, and 76 respectively represent the damped vibration waveforms of the spring mass damper system when the damping coefficients are 200Ns / m, 300Ns / m, and 350Ns / m. The maximum value of the amplitude of the shaft 12 in the present embodiment is the same as that of the spring mass damper system with a damping coefficient of 300Ns / m, and the damping speed is faster than that of the spring mass damper system with a damping coefficient of 300Ns / m. That is, it can be seen that the damper 18 for the rotating machine of the present embodiment has a damping performance with a damping coefficient of more than 300Ns / m in the radial direction.

[0063] Figure 5 1 is a diagram showing a damped vibration waveform (simulation result) when the shaft 12 is pulse-excited in the axial direction. The horizontal axis is time (ms) and the vertical axis is the amplitude (m) of the shaft 12. Figure 5 It can be seen that the damping coefficient of the rotating machine damper 18 according to the present embodiment is a relatively large damping coefficient of 84.4 Ns / m, that is, the rotating machine damper 18 according to the present embodiment has a relatively high damping performance in the axial direction.

[0064] According to the present embodiment, since the vibration of the shaft 12 can be damped without friction, the life of the rotating machine damper 18 can be extended compared to a friction type damper.

[0065] According to this embodiment, the vibration of the shaft 12 in both the axial and radial directions can be attenuated. By being able to attenuate the vibration of the shaft 12 in both the axial and radial directions, the durability of the bearing 16 that supports the load in both the axial and radial directions, for example, the total number of revolutions until failure occurs, can be improved. In addition, the stability of the shaft 12 can be improved thereby.

[0066] According to the present embodiment, the rotating machine damper 18 is configured as a magnetic damper, and thus the rotating machine damper 18 can be used in an extremely low temperature environment.

[0067] According to the present embodiment, the inner member 30 is preferably a non-magnetic member having a higher electrical conductivity in an extremely low temperature environment than in a normal temperature environment, such as aluminum. For example, the electrical conductivity of aluminum in an extremely low temperature environment is 23 times that in a normal temperature environment. Therefore, when the rotating machine 10 is used at an extremely low temperature, the damping performance of the rotating machine damper 18 is improved. In this case, the rotating machine 10 can be suitable for a liquid hydrogen pump of a rocket engine used at an extremely low temperature or an ultra-high pressure liquid hydrogen booster pump of a hydrogen station.

[0068] According to the present embodiment, eddy current is generated in the opposing portion 34 based on the magnetic flux penetrating the opposing portion 34 in the axial direction. Therefore, if the radial dimension of the opposing portion 34 is increased, the magnetic flux of the magnet 50 can be more effectively utilized, and the damping performance of the rotating machine damper 18 can be improved. That is, the damping performance of the rotating machine damper 18 can be improved while maintaining the axial thinness of the rotating machine damper 18.

[0069] The present disclosure has been described above based on the embodiments. The embodiments are illustrative, and those skilled in the art should understand that there may be various variations of the combination of its components and processing processes, and such variations are also included in the scope of the present disclosure. The following shows variations.

[0070] (First Modification)

[0071] Figure 6 This is an enlarged cross-sectional view showing the rotation support portion 14 and its surroundings of the rotating machine 10 according to the first modification example in an enlarged manner. Figure 6 Corresponds to Figure 2 The following description will focus on the differences from the embodiment.

[0072] The rotating machine damper 18 of this modified example has two magnets 52 in addition to the two magnets 50. The magnet 52 is fixed to the surface 44a on the axial inner side (the central side of the rotating machine damper 18 in the axial direction) of the cover portion 44. The opposing portion 34 and the magnet 52 are axially opposed to each other with a predetermined gap therebetween. In detail, the surface 34c on the axial inner side of the opposing portion 34 is opposed to the magnet 50, and the surface 34d on the axial outer side of the opposing portion 34 (the opposite side of the magnet support portion 46 in the axial direction) is opposed to the magnet 52. That is, in this modified example, the two end surfaces of the opposing portion 34 in the axial direction are opposed to the magnets.

[0073] The magnet 52 is a permanent magnet. The magnet 52 is magnetized in such a way that the two ends in the axial direction become different magnetic poles. In detail, in the magnet 52, the N pole as one magnetic pole surface is axially opposed to the axially outer surface 34d of the opposing portion 34 with a predetermined gap, and the S pole as the other magnetic pole surface is in contact with the axially inner surface 44a of the cover portion 44. That is, the magnet 52 is the same as the magnet 50, and the axially inner magnetic pole surface is the N pole, and the axially outer magnetic pole surface is the S pole. In addition, the N pole and the S pole of the magnet 50 may be opposite, in which case, the N pole and the S pole of the magnet 52 are also opposite. For the same reason as the magnet 50, the magnetic flux density of the magnet 52 may also be uneven in the radial direction. The magnet 52 is formed into a ring shape that is continuous in the circumferential direction. In addition, the magnet 52 may also be formed at intervals in the circumferential direction.

[0074] In this modification, the same magnetic circuit M as that in the embodiment is configured.

[0075] In this modified example, when the inner member 30 is displaced along with the displacement of the shaft 12, eddy currents are generated not only on the axially inner surface 34c of the opposing portion 34 opposing the magnet 50, but also on the axially outer surface 34d of the opposing portion 34 opposing the magnet 52. That is, more eddy currents are generated. As a result, a higher damping force is obtained.

[0076] According to this modification, the same effects as those of the embodiment can be achieved. According to this modification, as described above, eddy currents are generated on both surfaces 34c and 34d of the facing portion 34, so that a higher damping force can be obtained.

[0077] (Second Modification)

[0078] Figure 7 This is an enlarged cross-sectional view showing the rotation support portion 14 and its surroundings of the rotating machine 10 according to the second modified example in an enlarged manner. Figure 7 Corresponds to Figure 6 The following description will focus on the differences from the first modification example.

[0079] The rotating machine damper 18 of the present modified example further includes two side auxiliary magnets 60 and one central auxiliary magnet 62 .

[0080] The side auxiliary magnet 60 is arranged on the axially outer side of the magnet 52 (the side opposite to the magnet support portion 46 in the axial direction) and the radially inner side of the cover portion 44. The side auxiliary magnet 60 is not particularly limited, and can be fixed to the axially outer surface 52a of the magnet 52 and the radially inner surface 44b of the cover portion 44. In addition, the side auxiliary magnet 60 can be fixed only to the axially outer surface 52a of the magnet 52, or only to the radially inner surface 44b of the cover portion 44.

[0081] The side auxiliary magnet 60 is a permanent magnet. The side auxiliary magnet 60 is magnetized in such a manner that the two ends in the radial direction become different magnetic poles. In detail, in the side auxiliary magnet 60, the N pole as one magnetic pole surface faces radially outward, and the S pole as the other magnetic pole surface faces radially inward. In addition, in the case where the N pole and S pole of the magnets 50 and 52 are opposite, the N pole and S pole of the side auxiliary magnet 60 are also opposite. That is, the side auxiliary magnet 60 is magnetized in such a manner that the magnetic pole on the radial outside is the same as the magnetic pole on the axial outside of the magnets 50 and 52. In short, the side auxiliary magnet 60 produces an axial change in magnetic flux density. The side auxiliary magnet 60 is formed in a ring shape that is continuous in the circumferential direction. In addition, the side auxiliary magnet 60 can also be formed at intervals in the circumferential direction.

[0082] The central auxiliary magnet 62 is disposed between the two magnets 50 and radially inside the magnet support portion 46. The central auxiliary magnet 62 is not particularly limited, and may be fixed to the axially inner surface 50a of the magnet 50 and the radially inner surface 46c of the magnet support portion 46. In addition, the central auxiliary magnet 62 may be fixed only to the axially inner surface 50a of the magnet 50 or only to the radially inner surface 46c of the magnet support portion 46.

[0083] The central auxiliary magnet 62 is a permanent magnet. The central auxiliary magnet 62 is magnetized in such a manner that the two ends in the radial direction become mutually different magnetic poles. In detail, in the central auxiliary magnet 62, the N pole as one magnetic pole surface faces radially inward, and the S pole as the other magnetic pole surface faces radially outward. In addition, in the case where the N pole and S pole of the magnets 50 and 52 are opposite, the N pole and S pole of the central auxiliary magnet 62 are also opposite. That is, the central auxiliary magnet 62 is magnetized in such a manner that the magnetic pole on the radial inside is the same as the magnetic pole on the axial inside of the magnets 50 and 52. In short, the central auxiliary magnet 62 produces an axial change in magnetic flux density. The central auxiliary magnet 62 is formed into a ring shape that is continuous in the circumferential direction. In addition, the central auxiliary magnet 62 can also be formed at intervals in the circumferential direction.

[0084] The auxiliary magnets 60 and 62 are not particularly limited, and may be arranged so that at least a portion overlaps with the magnets 50 and 52 when viewed in the axial direction. Figure 7 As shown, the auxiliary magnets 60 and 62 may be arranged so as to overlap with the magnets 50 and 52 as a whole when viewed in the axial direction.

[0085] The magnets 50 and 52 together with the magnet support portion 46, the outer peripheral portion 42 and the cover portion 44 constitute the main magnetic circuit M1. The magnetic flux of the magnetic circuit M1 penetrates the opposing portion 34 in the axial direction. The magnetic circuit M1 provides the opposing portion 34 with a magnetic flux density distribution that changes according to the displacement of the opposing portion 34 accompanying the vibration of the shaft 12. Specifically, the magnetic circuit M1 provides the opposing portion 34 with a magnetic flux density distribution that is non-uniform in the radial direction. This can be achieved, for example, by making the magnetic flux density of the magnets 50 and 52 non-uniform in the radial direction. The magnetic flux density in the opposing portion 34 is non-uniform in the radial direction, and thus the magnetic flux penetrating the opposing portion 34 in the axial direction changes when the opposing portion 34 is displaced in the radial direction due to the vibration of the shaft 12. With respect to the axial direction, the magnetic flux density in the opposing portion 34 changes according to the distance between the magnets 50 and 52 and the opposing portion 34. Therefore, when the facing portion 34 is displaced in the axial direction due to the vibration of the shaft 12 , the magnetic flux penetrating the facing portion 34 in the axial direction changes.

[0086] The side auxiliary magnets 60 and the central auxiliary magnet 62 constitute the auxiliary magnetic circuit M2 together with the cover portion 44, the magnet support portion 46, and the bearing support portion 32. In addition, a structure in which the rotating machine damper 18 only includes the side auxiliary magnets 60 but does not include the central auxiliary magnet 62 can also be considered. In this case, the side auxiliary magnets 60 also constitute the auxiliary magnetic circuit M2 together with the cover portion 44, the magnet support portion 46, and the bearing support portion 32.

[0087] The magnetic flux of the auxiliary magnetic circuit M2 overlaps the magnetic flux of the main magnetic circuit M1. The direction of the magnetic flux of the main magnetic circuit M1 and the direction of the magnetic flux of the auxiliary magnetic circuit M2 are the same in the overlapping part. Therefore, under the action of the magnetic flux of the auxiliary magnetic circuit M2, the magnetic flux of the main magnetic circuit M1 is enhanced.

[0088] In addition, as long as the effect of enhancing the magnetic flux of the main magnetic circuit M1 is obtained through the magnetic flux of the auxiliary magnetic circuit M2, in other words, as long as the magnetic flux of the main magnetic circuit M1 and the magnetic flux of the auxiliary magnetic circuit M2 overlap and the directions of their respective magnetic fluxes in the overlapping part are the same, the auxiliary magnets 60, 62 do not have to overlap with the magnets 50, 52 when viewed in the axial direction.

[0089] In this modification, similarly to the first modification, when the inner member 30 is displaced along with the displacement of the shaft 12 , eddy currents are generated on both surfaces 34 c and 34 d of the facing portion 34 , and as a result, a damping force is obtained.

[0090] Next, the present inventors conducted a simulation under the same conditions as the simulation of the embodiment in order to confirm the damping performance of the rotating machine damper 18 according to the present modification.

[0091] Figure 8 1 is a diagram showing the heat density distribution (simulation result) when the shaft 12 is pulse-excited in the radial direction. Figure 8 The distribution of the time when the eddy current loss is most significant is shown in FIG. Fig.10 The same is true.

[0092] Figure 8 The three heat density distributions are shown in order from left to right for the present modification, the embodiment, and the first modification. Since the eddy current generates heat, the generation of the eddy current can be known from the heat density distribution. Figure 8 It can be seen that the heat generation density of the opposing portion 34 is higher in this modification than in the embodiment and the first modification, that is, more eddy currents are generated in the opposing portion 34 in this modification than in the embodiment and the first modification. Figure 8 It is understood that in the present modification, more eddy currents are generated in the portion of the bearing support portion 32 facing the magnets 50 , 52 in the radial direction, compared with the embodiment and the first modification.

[0093] Fig. 9 It is a diagram showing the damped vibration waveform (simulation result) when the shaft 12 is pulse-excited in the radial direction. The horizontal axis is time (ms), and the vertical axis is the amplitude (dimensionless quantity) of the shaft 12. Curve 78 represents the damped vibration waveform of this modification. Curves 80 and 82 represent the damped vibration waveforms of the implementation method and the first modification, respectively. The maximum value of the amplitude of the shaft 12 is the smallest in this modification, and the damping speed is also the fastest in this modification. That is, it can be seen that the rotary machine damper 18 of this modification has a relatively high damping performance in the radial direction.

[0094] from Figure 8-Figure 9 It is understood that when the inner member 30 is displaced in the radial direction along with the displacement of the shaft 12 , relatively large eddy currents are generated in the facing portion 34 and the bearing support portion 32 , and as a result, a high damping force is obtained in the radial direction.

[0095] Fig.10 It is a diagram showing the heat density distribution (simulation result) when the shaft 12 is pulse-excited in the axial direction. Fig.10 The three heat density distributions of FIG. 1 show the heat density distributions of this modification, the embodiment, and the first modification from the left. Fig.10 It can be seen that in this modification, a relatively large amount of eddy current is generated in the portion of the opposing portion 34 that is axially opposed to the corner of the magnets 50 and 52. It can also be seen that in this modification, a larger amount of eddy current is generated in the portion of the bearing support portion 32 that is radially opposed to the auxiliary magnets 60 and 62 than in the embodiment and the first modification.

[0096] Fig.11 It is a diagram showing the damped vibration waveform (simulation result) when the shaft 12 is pulse-excited in the axial direction. The horizontal axis is time (ms), and the vertical axis is the amplitude (dimensionless quantity) of the shaft 12. Curve 84 represents the damped vibration waveform of this modification. Curves 86 and 88 represent the damped vibration waveforms of the implementation method and the first modification, respectively. The maximum value of the amplitude of the shaft 12 in this modification is the smallest, and the damping speed is the fastest. That is, it can be seen that the damper 18 for the rotating machine of this modification has a relatively high damping performance in the axial direction.

[0097] from Figure 10-11 It is understood that when the inner member 30 is displaced in the axial direction in accordance with the displacement of the shaft 12 , relatively large eddy currents are generated in the facing portion 34 and the bearing support portion 32 , and as a result, a high damping force is obtained in the axial direction.

[0098] According to this modification, the same effect as the first modification can be achieved. In addition, according to this modification, more eddy currents are generated in the opposing portion 34 and the bearing support portion 32, thereby obtaining a higher damping force. That is, a higher damping performance can be achieved. In addition, according to this modification, the axial magnetic flux density change is compensated by the action of the auxiliary magnets 60 and 62, thereby obtaining a stronger damping force in the axial direction.

[0099] (Third Modification)

[0100] Fig.12 It is an enlarged cross-sectional view showing enlargedly the rotation support portion 14 and its periphery of the rotating machine 10 according to the third modified example. Fig.12 Corresponds to Figure 2 The following description will focus on the differences from the embodiment.

[0101] The inner member 30 includes: a bearing support portion 32, an opposing portion 34, and a connecting portion 36 for connecting the bearing support portion 32 and the opposing portion 34. In this modification, the opposing portion 34 is cylindrical and surrounds the bearing support portion 32 and the magnet 50. The connecting portion 36 can be formed to be continuous in the circumferential direction, that is, to be formed in an annular shape, or can be formed at intervals in the circumferential direction. In this modification, the opposing portion 34 and the magnet 50 are radially opposed with a predetermined gap therebetween. The inner member 30 is similar to the embodiment, and at least the opposing portion 34 has conductivity.

[0102] The outer member 40 includes an outer peripheral portion 42, two cover portions 44, and two magnet support portions 46 extending axially inward (axially toward the center of the rotating machine damper 18) from the inner peripheral ends of the two cover portions 44. Magnets 50 are fixed to the outer peripheral surfaces 46c of the two magnet support portions 46.

[0103] The magnet 50 is magnetized so that both ends in the radial direction have different magnetic poles. Specifically, in the magnet 50, the N pole as one magnetic pole surface is radially opposed to the inner peripheral surface 34a of the opposing portion 34 with a predetermined gap therebetween, and the S pole as the other magnetic pole surface is in contact with the outer peripheral surface 46c of the magnet support portion 46. In addition, the N pole and the S pole of the magnet 50 may be opposite.

[0104] The outer member 40 is a magnetic body, preferably a soft magnetic body, similarly to the embodiment. The outer peripheral portion 42 of the outer member 40 is opposite to the N pole of the magnet 50, and the magnet support portion 46 is opposite to (contacts) the S pole of the magnet 50. Therefore, the magnetic flux emitted from the N pole of the magnet 50 passes through the opposing portion 34 in the radial direction, and then returns to the S pole through the outer peripheral portion 42, the cover portion 44, and the magnet support portion 46 in sequence. That is, the outer member 40 functions as a yoke constituting a part of the magnetic circuit similarly to the embodiment.

[0105] The magnet 50, the outer peripheral portion 42, the cover portion 44, and the magnet support portion 46 constitute a magnetic circuit M. The magnetic flux of the magnetic circuit M penetrates the opposing portion 34 in the radial direction. The magnetic circuit M provides the opposing portion 34 with a magnetic flux density distribution that changes according to the displacement of the opposing portion 34 accompanying the vibration of the shaft 12. Specifically, the magnetic circuit M provides the opposing portion 34 with a magnetic flux density distribution that is non-uniform in the axial direction. This can be achieved, for example, by the non-uniformity of the magnetic flux density of the magnet 50 in the axial direction. The magnetic flux density in the opposing portion 34 is non-uniform in the axial direction, and when the opposing portion 34 is displaced in the axial direction due to the vibration of the shaft 12, the magnetic flux penetrating the opposing portion 34 in the radial direction changes. With respect to the radial direction, the magnetic flux density in the opposing portion 34 changes according to the distance between the magnet 50 and the opposing portion 34. Therefore, when the opposing portion 34 is displaced in the radial direction due to the vibration of the shaft 12, the magnetic flux penetrating the opposing portion 34 in the radial direction changes.

[0106] In this modification, similarly to the embodiment, when the inner member 30 is displaced along with the displacement of the shaft 12 , an eddy current is generated in the facing portion 34 , and as a result, a damping force is obtained.

[0107] According to this modification, the same effects as those of the embodiment can be achieved. In addition, according to this modification, eddy currents are generated in the opposing portion 34 based on the magnetic flux that penetrates the opposing portion 34 in the radial direction. Therefore, if the axial dimension of the opposing portion 34 is increased, the magnetic flux of the magnet 50 can be more effectively utilized. That is, the damping performance of the rotating machine damper 18 can be improved while maintaining the radial dimension of the rotating machine damper 18.

[0108] (Fourth Modification)

[0109] Fig.13 It is an enlarged cross-sectional view showing enlargedly the rotation support portion 14 and its periphery of the rotating machine 10 according to the fourth modification. Fig.13 Corresponds to Figure 2 The following description will focus on the differences from the embodiment.

[0110] The inner member 30 includes a bearing support portion 32 and an opposing portion 34. The bearing support portion 32 is radially opposed to the magnet 50 and the inwardly protruding portion 48 of the outer member 40 via the opposing portion 34. The opposing portion 34 is, for example, cylindrical and surrounds the bearing support portion 32 and is fixed to the bearing support portion 32. In this modified example, the opposing portion 34 is radially opposed to the magnet 50 via a predetermined gap. The inner member 30 is similar to the embodiment, and at least the opposing portion 34 has conductivity.

[0111] The outer member 40 includes an outer peripheral portion (magnet support portion) 42 and an inwardly protruding portion 48 protruding radially inward from the axial center of the outer peripheral portion 42. Two magnets 50 are fixed to the inner peripheral surface 42a of the outer peripheral portion 42 with the inwardly protruding portion 48 interposed therebetween.

[0112] The magnet 50 is magnetized so that both ends in the radial direction have different magnetic poles. Specifically, in the magnet 50, the N pole as one magnetic pole surface abuts against the inner peripheral surface 42a of the outer peripheral portion 42, and the S pole as the other magnetic pole surface faces the outer peripheral surface 34b of the opposing portion 34 in the radial direction with a predetermined gap therebetween. In addition, the N pole and the S pole of the magnet 50 may be opposite.

[0113] The outer component 40 is a magnetic body, preferably a soft magnetic body, in the same manner as in the embodiment. In addition, the bearing support portion 32 of this modified example is a magnetic body, preferably a soft magnetic body, in the same manner as the outer component 40. The outer peripheral portion 42 of the outer component 40 is opposite (contacting) to the N pole of the magnet 50, and the bearing support portion 32 of the inner component 30 is opposite to the S pole of the magnet 50. In addition, the inward protrusion 48 of the outer component 40 is close to the bearing support portion 32 of the inner component 30. Therefore, the magnetic flux emitted from the N pole of the magnet 50 returns to the S pole through the outer peripheral portion 42 of the outer component 40, the inward protrusion 48, and the bearing support portion 32 of the inner component 30 in sequence. That is, the outer component 40 and the bearing support portion 32 of the inner component function as a yoke constituting a part of the magnetic circuit.

[0114] The magnet 50, the outer peripheral portion 42 of the outer member 40, the inward protrusion 48, and the bearing support portion 32 of the inner member 30 constitute a magnetic circuit M. The magnetic circuit M in which the magnetic flux of the magnetic circuit M penetrates the opposing portion 34 in the radial direction provides the opposing portion 34 with a magnetic flux density distribution in which the magnetic flux penetrating the opposing portion 34 changes according to the displacement of the opposing portion 34 accompanying the vibration of the shaft 12. Specifically, the magnetic circuit M provides the opposing portion 34 with a magnetic flux density distribution in which the magnetic flux density is non-uniform in the axial direction. This can be achieved, for example, by making the magnetic flux density of the magnet 50 non-uniform in the axial direction. The magnetic flux density in the opposing portion 34 is non-uniform in the axial direction, and thus, when the opposing portion 34 is displaced in the axial direction due to the vibration of the shaft 12, the magnetic flux penetrating the opposing portion 34 in the radial direction changes. With respect to the radial direction, the magnetic flux density in the opposing portion 34 changes according to the distance between the magnet 50 and the opposing portion 34. Therefore, when the facing portion 34 is displaced in the radial direction due to the vibration of the shaft 12 , the magnetic flux penetrating the facing portion 34 in the radial direction changes.

[0115] In this modification, similarly to the embodiment, when the inner member 30 is displaced along with the displacement of the shaft 12 , an eddy current is generated in the facing portion 34 , and as a result, a damping force is obtained.

[0116] According to this modification, the same effects as those of the third modification can be achieved.

[0117] (Fifth Modification)

[0118] In the embodiment and the above-mentioned modification, the magnet 50 is fixed to the outer member 40 and eddy current is generated in the opposing portion 34 of the inner member 30. However, as a modification, the magnet 50 may be fixed to the inner member 30 and eddy current may be generated in the outer member.

[0119] Fig.14 It is an enlarged cross-sectional view showing the rotation support portion 14 and its surroundings of the rotating machine 10 according to the fifth modification example in an enlarged manner. Fig.14 Corresponds to Figure 2 The following description will focus on the differences from the embodiment.

[0120] The outer member 40 includes: an outer peripheral portion 42 and two opposing portions 144 that are respectively opposed to the magnetic pole faces of the magnet 50. The opposing portions 144 protrude radially inward from the outer peripheral portion 42. In this modification, the opposing portions 144 and the magnet 50 are axially opposed with a predetermined gap therebetween. The outer member 40 is similar to the inner member 30 of the embodiment, and at least the opposing portions 144 have conductivity, and are preferably non-magnetic, such as aluminum.

[0121] The inner member 30 includes: a bearing support portion 32; a cover portion 134, which protrudes radially outward from both ends of the bearing support portion 32 in the axial direction; and a magnet support portion 136, which supports the magnet 50. In this modification, the magnet support portion 136 protrudes radially outward from the center of the bearing support portion 32 in the axial direction. The magnet support portion 136 is formed continuously or at intervals in the circumferential direction similarly to the magnet support portion 46 of the embodiment, and the magnets 50 are fixed to the two end surfaces 136a and 136b in the axial direction, respectively.

[0122] The cover portion 134 faces the magnet 50 via the facing portion 144 in the axial direction.

[0123] The inner part 30 is a magnetic body, preferably a soft magnetic body. As described above, the magnet support portion 136 of the inner part 30 is opposite (contacting) to the N pole of the magnet 50, and the cover portion 134 is opposite to the S pole of the magnet 50. Therefore, the magnetic flux emitted from the N pole of the magnet 50 passes through the magnet support portion 136, the bearing support portion 32, and the cover portion 134 in sequence, passes through the opposing portion 144 in the axial direction, and returns to the S pole. That is, the inner part 30 functions as a yoke constituting a part of the magnetic circuit. As a result, the cancellation of magnetic flux is suppressed, and in addition, the leakage magnetic flux is reduced, and the magnetic efficiency is improved.

[0124] The magnet 50, the magnet support portion 136, the bearing support portion 32, and the cover portion 134 constitute a magnetic circuit M. The magnetic flux of the magnetic circuit M penetrates the opposing portion 144 in the radial direction. The magnetic circuit M provides the opposing portion 144 with a magnetic flux density distribution that changes according to the displacement of the opposing portion 144 accompanying the vibration of the shaft 12. Specifically, the magnetic circuit M provides the opposing portion 144 with a magnetic flux density distribution that is non-uniform in the radial direction. This can be achieved, for example, by making the magnetic flux density of the magnet 50 non-uniform in the axial direction. The magnetic flux density in the opposing portion 144 is non-uniform in the axial direction, and thus, when the opposing portion 144 is displaced in the axial direction due to the vibration of the shaft 12, the magnetic flux penetrating the opposing portion 144 in the radial direction changes. With respect to the radial direction, the magnetic flux density in the opposing portion 144 changes according to the distance between the magnet 50 and the opposing portion 144. Therefore, when the facing portion 144 is displaced in the radial direction due to the vibration of the shaft 12 , the magnetic flux penetrating the facing portion 144 in the radial direction changes.

[0125] In the present modification, when the magnet 50 is displaced along with the displacement of the shaft 12 , an eddy current is generated in the facing portion 144 , and as a result, a damping force is obtained.

[0126] According to this modification, the same operational effects as those of the embodiment can be achieved.

[0127] As a further modification, similarly to the first modification, the rotating machine damper 18 may further include two magnets 52 fixed to the axially inner surfaces of the two cover portions 134. In addition, similarly to the second modification, the rotating machine damper 18 may further include two side auxiliary magnets 60 and one central auxiliary magnet 62. The two side auxiliary magnets 60 may be arranged axially outside the magnets 52 and radially inside the cover portion 134. The central auxiliary magnet 62 may be arranged between the two magnets 50 and radially outside the magnet support portion 136.

[0128] (Sixth Modification)

[0129] Different from the embodiment and the above-described modified examples, the magnet 50 may be a Halbach array magnet.

[0130] Fig.15 This is an enlarged cross-sectional view showing an enlarged view of the rotation support portion 14 and its surroundings of the rotating machine 10 according to the sixth modification. Fig.15 Corresponds to Figure 2 The following description will focus on the differences from the embodiment.

[0131] The magnet 50 is a Halbach array magnet configured so that the magnetic flux density on the facing portion 34 side becomes higher.

[0132] In detail, the magnet 50 includes a plurality of magnets 50_1 to 50_5 stacked in the radial direction. In addition, the number of magnets constituting the magnet 50 is not particularly limited. The magnet 50_1 is located at the innermost side in the radial direction, the magnet 50_2 surrounds the magnet 50_1, the magnet 50_3 surrounds the magnet 50_2, the magnet 50_4 surrounds the magnet 50_3, and the magnet 50_5 surrounds the magnet 50_4. The magnets 50_1, 50_3, and 50_5 are magnetized in such a manner that the two ends in the axial direction become magnetic poles different from each other. The magnets 50_1 and 50_5 are magnetized in such a manner that the axial outer side is the N pole and the axial inner side is the S pole. The magnet 50_3 is magnetized in such a manner that the axial inner side is the N pole and the axial outer side is the S pole. The magnets 50_2 and 50_4 are magnetized in such a manner that the two ends in the radial direction become magnetic poles different from each other. The magnet 50_2 is magnetized in such a manner that the radial inner side is the N pole and the radial outer side is the S pole. The magnet 50_4 is magnetized so that the radially outer side is the N pole and the radially inner side is the S pole.

[0133] In this modification, similarly to the embodiment, when the inner member 30 is displaced along with the displacement of the shaft 12 , an eddy current is generated in the facing portion 34 , and as a result, a damping force is obtained.

[0134] Next, the present inventors conducted a simulation under the same conditions as the simulation of the embodiment in order to confirm the damping performance of the rotating machine damper 18 according to the present modification.

[0135] Fig.16 It is a diagram showing the damped vibration waveform (simulation result) when the shaft 12 is pulse-excited in the axial direction. The horizontal axis is time (ms), and the vertical axis is the amplitude (dimensionless quantity) of the shaft 12. Curve 90 represents the damped vibration waveform of this variant. Curves 92, 94, and 96 represent the damped vibration waveforms of the implementation example, the first variant, and the second variant, respectively. The maximum value of the amplitude of the shaft 12 is the smallest in this variant, and the damping speed is also the fastest in this variant. That is, it can be seen that the damper 18 for the rotating machine of this variant has a relatively high damping performance in the axial direction.

[0136] Furthermore, it was confirmed through simulation that the rotating machine damper 18 of the present modification has the same level of damping performance in the radial direction as that of the embodiment.

[0137] According to this modification, the same effects as those of the embodiment can be achieved. In addition, in this modification, the magnet 50 is a Halbach array magnet, so when the inner member 30 is displaced in the axial direction along with the displacement of the shaft 12, the change amount of the magnetic flux penetrating the opposing portion 34 in the axial direction is high, so that a large amount of eddy current is generated in the opposing portion 34. As a result, a high damping force is obtained in the axial direction.

[0138] As a further modification, the outer member 40 may be a non-magnetic body. That is, the outer member 40 may not function as a yoke. This is because the magnet 50 is a Halbach array magnet, and its magnetic flux is concentrated on the opposing portion 34 side. Therefore, even if the outer member 40 is not used as a yoke, the leakage magnetic flux to the opposite side of the opposing portion 34 is small. In this case, the outer member 40 does not need to make it easy for the magnetic flux to pass through, so it can be made relatively thin.

[0139] (Seventh Modification)

[0140] Fig.17 It is an enlarged cross-sectional view showing in enlarged form the rotation support portion 14 and its periphery of the rotating machine 10 according to the seventh modification. Fig.17 Corresponds to Fig.15 This modification is a modification obtained by combining the first modification with the sixth modification. The following description will focus on the differences from the sixth modification.

[0141] The rotating machine damper 18 of the present modification example includes two magnets 52 in addition to the two magnets 50 , similarly to the first modification example.

[0142] The magnets 50 and 52 are both Halbach array magnets configured so that the magnetic flux density becomes higher on the facing portion 34 side. The magnets 50 and 52 facing each other with the facing portion 34 interposed therebetween constitute a so-called double Halbach array magnet 54 .

[0143] As described above, the magnets 50 and 52 are magnets of the Halbach array, and the magnetic flux thereof is concentrated on the opposing portion 34 side, so a yoke is not required for suppressing the leakage magnetic flux to the opposite side of the opposing portion 34. That is, it is not necessary to make the outer component 40 function as a yoke constituting a part of the magnetic circuit. Therefore, the outer component 40 is a non-magnetic body. In addition, in order to facilitate the passage of magnetic flux when the outer component 40 constitutes a part of the magnetic circuit, it is necessary to make the outer component 40 thicker, but in this modified example, since the outer component 40 does not constitute a part of the magnetic circuit, that is, it is not necessary to facilitate the passage of magnetic flux, the outer component 40 can be made thinner. In addition, of course, the outer component 40 can also function as a yoke.

[0144] Since the outer member 40 is a non-magnetic body, the magnets 50 and 52 constitute the magnetic circuit M alone.

[0145] In this modification, similarly to the embodiment, when the inner member 30 is displaced along with the displacement of the shaft 12 , an eddy current is generated in the facing portion 34 , and as a result, a damping force is obtained.

[0146] According to this modification, the same effects as those of the sixth modification and the first modification can be achieved. In addition, according to this modification, the outer member 40 only needs to support the magnets 50 and 52, and does not need to function as a yoke, so it can be made thinner. Therefore, the outer member 40 and even the rotating machine damper 18 can be made lighter.

[0147] (Eighth Modification)

[0148] Fig.18 It is an enlarged cross-sectional view showing in enlarged form the rotation support portion 14 and its periphery of the rotating machine 10 according to the eighth modification. Fig.18 Corresponds to Fig.17 This modification is a modification obtained by combining the second modification with the seventh modification. The description will focus on the differences from the seventh modification.

[0149] The rotating machine damper 18 of the present modification further includes two side auxiliary magnets 60 and one central auxiliary magnet 62 similarly to the second modification.

[0150] The side auxiliary magnets 60 are arranged axially with the innermost magnet 52_1 of the plurality of magnets constituting the Halbach array magnet 52. The side auxiliary magnets 60 and the magnet 52_1 together constitute the Halbach array magnet 56 having a high magnetic flux density on the bearing support portion 32 (the other opposing portion) side.

[0151] Similarly, the central auxiliary magnet 62 is arranged axially with the innermost magnet 50_1 of the plurality of magnets constituting the Halbach array magnet 50. The central auxiliary magnet 62 and the magnet 50_1 together constitute the Halbach array magnet 58 having a high magnetic flux density on the bearing support portion 32 side.

[0152] In this modification, similarly to the embodiment, when the inner member 30 is displaced along with the displacement of the shaft 12 , an eddy current is generated in the facing portion 34 , and as a result, a damping force is obtained.

[0153] Fig.19 It is a diagram showing the damped vibration waveform (simulation result) when the shaft 12 is pulse-excited in the radial direction. The horizontal axis is time (ms), and the vertical axis is the amplitude (dimensionless quantity) of the shaft 12. Curve 102 represents the damped vibration waveform of this variant. Curves 104 and 106 represent the damped vibration waveforms of the second variant and the seventh variant, respectively. The maximum value of the amplitude of the shaft 12 is the smallest in this variant, and the damping speed is also the fastest in this variant. That is, it can be seen that the rotating machine damper 18 of this variant has a relatively high damping performance in the radial direction.

[0154] Fig. 20It is a diagram showing the damped vibration waveform (simulation result) when the shaft 12 is pulse-excited in the axial direction. The horizontal axis is time (ms), and the vertical axis is the amplitude (dimensionless quantity) of the shaft 12. Curve 112 represents the damped vibration waveform of this variant. Curves 114 and 116 represent the damped vibration waveforms of the second variant and the seventh variant, respectively. The maximum value of the amplitude of the shaft 12 is the smallest in this variant, and the damping speed is also the fastest in this variant. That is, it can be seen that the damper 18 for the rotating machine of this variant has a relatively high damping performance in the axial direction.

[0155] According to this modification, the same effects as those of the seventh modification and the second modification can be achieved. In addition, according to this modification, the auxiliary magnets 60 and 62 together with the magnets 50_1 and 52_1 form a Halbach array, which generates more eddy currents in the bearing support portion 32, thereby obtaining a higher damping force. That is, a higher damping performance can be achieved.

[0156] (Ninth Modification)

[0157] Although not specifically mentioned in the sixth to eighth modifications, Fig.12 The third variant of Fig.13 A fourth variation of Fig.14 The same is true for the rotating machine damper 18 of the fifth modified example, and the magnet 50 may also be a Halbach array magnet. Figure 6 The first variant example and Figure 7 The rotating machine damper 18 according to the second modified example may be configured such that only one of the magnet 50 and the magnet 52 is a Halbach array magnet.

[0158] (Each mode of the present disclosure) A damper for a rotating machine of a certain mode of the present disclosure is a damper for a rotating machine of a rotating machine, and includes: an inner member capable of supporting a bearing for rotatably supporting a shaft of the rotating machine; an outer member disposed on the outer peripheral side of the inner member; and a magnet. One of the inner member and the outer member is a conductive member, the magnet is fixed to the other of the inner member and the outer member, and is opposed to one of the inner member and the outer member with a gap therebetween, the inner member is capable of displacement in the axial direction and radial direction of the shaft, and the axial and radial vibrations of the shaft are attenuated by the electromagnetic induced electromotive force based on the displacement of the inner member.

[0159] In one embodiment, the magnet and the other of the inner member and the outer member form a magnetic circuit that provides the inner member and the outer member with a magnetic flux density distribution in which the magnetic flux passing through the one of the inner member and the outer member changes according to the displacement of the inner member.

[0160] In one embodiment, the inner member is a conductive member, the magnet is fixed to the outer member, and the magnet and the outer member form a magnetic circuit that provides the inner member with a magnetic flux density distribution in which the magnetic flux passing through the inner member changes according to the displacement of the inner member.

[0161] In one embodiment, the outer member is a conductive member, the magnet is fixed to the inner member, and the magnet and the inner member form a magnetic circuit that provides the outer member with a magnetic flux density distribution in which the magnetic flux passing through the outer member changes according to the displacement of the inner member.

[0162] In one embodiment, the inner member and the outer member are cylindrical.

[0163] According to these aspects, the life of the rotating machine damper can be prolonged.

[0164] In one embodiment, the magnet is magnetized so that both ends in the axial direction have magnetic poles different from each other, and one of the inner member and the outer member has an opposing portion that opposes the magnet in the axial direction.

[0165] According to this aspect, while maintaining the axial thickness of the rotating machine damper, the surface area of ​​the conductive member that generates eddy current can be increased, thereby more effectively utilizing the magnetic flux of the magnet.

[0166] In a certain embodiment, there is also another magnet, which is fixed to the other side of the inner component and the outer component and is opposite to one side of the inner component and the outer component with a gap therebetween. The other magnet is arranged on the side opposite to the magnet of the axially opposing portion and is opposite to the opposing portion in the axial direction. The magnet and the other magnet are both magnets of a Halbach array configured in such a way that the magnetic flux density on the opposing portion side becomes higher.

[0167] According to this aspect, the outer member and thus the rotating machine damper can be made relatively light.

[0168] In one embodiment, an auxiliary magnet is further provided, which is fixed to the other of the inner member and the outer member, is magnetized so that both ends in the radial direction have magnetic poles different from each other, and generates magnetic flux for strengthening the direction of the magnetic flux generated by the magnet.

[0169] In a certain embodiment, the magnet is a magnet of a Halbach array constructed in a manner such that the magnetic flux density on the opposing portion side becomes higher, and one of the inner component and the outer component has another opposing portion axially opposed to the magnet and the auxiliary magnet, and the auxiliary magnet together with the magnet constitutes a magnet of a Halbach array constructed in a manner such that the magnetic flux density on the other opposing portion side becomes higher.

[0170] According to these aspects, higher damping performance can be achieved, and the life of the rotating machine damper can be further prolonged.

[0171] In one embodiment, the other of the inner member and the outer member is a magnetic body also serving as a yoke.

[0172] According to this aspect, the leakage magnetic flux is reduced and the magnetic efficiency is improved.

[0173] A rotating machine according to one aspect of the present disclosure includes: the above-described rotating machine damper; a bearing supported by an inner member of the rotating machine damper; and a shaft rotatably supported by the bearing.

[0174] According to this aspect, the life of the rotating machine damper can be extended.

[0175] In one embodiment, a rotating machine includes: a plurality of rotating machine dampers; and a plurality of bearings corresponding to the plurality of rotating machine dampers and supported by inner members of the corresponding rotating machine dampers, respectively. A shaft is rotatably supported by the plurality of bearings.

[0176] According to this aspect, the shaft can be supported more stably.

[0177] In one embodiment, the rotating machine is used in an extremely low temperature environment.

[0178] (Industrial Applicability)

[0179] The present disclosure relates to a damper for a rotating machine and a rotating machine including the damper for a rotating machine.

[0180] (Explanation of Reference Numerals)

[0181] 10 rotating machine, 12 shaft, 16 bearing, 18 damper for rotating machine, 30 inner member, 34, 144 opposing parts, 40 outer member, 50 magnet.

Claims

1. A damper for a rotating machine, comprising: an inner member capable of supporting a bearing for rotatably supporting a shaft of the rotating machine; an outer member disposed on an outer peripheral side of the inner member; and magnet, One of the inner member and the outer member is a conductive member, The magnet is fixed to the other of the inner member and the outer member and faces one of the inner member and the outer member with a gap therebetween. The inner member is displaceable in the axial direction and radial direction of the shaft, The axial and radial vibrations of the shaft are attenuated by the electromagnetic induced electromotive force due to the displacement of the inner member.

2. The damper for a rotating machine according to claim 1, wherein: The magnet and the other of the inner member and the outer member form a magnetic circuit that provides the magnetic flux passing through the one of the inner member and the outer member with a magnetic flux density distribution that changes according to the displacement of the inner member.

3. The damper for a rotating machine according to claim 1, wherein: The inner part is a conductive part, and the magnet is fixed to the outer part. The magnet and the outer member constitute a magnetic circuit that provides the inner member with a magnetic flux density distribution in which the magnetic flux passing through the inner member changes according to the displacement of the inner member.

4. The damper for a rotating machine according to claim 1, wherein: The outer member is a conductive member, and the magnet is fixed to the inner member. The magnet and the inner member constitute a magnetic circuit that provides the outer member with a magnetic flux density distribution in which the magnetic flux passing through the outer member changes according to the displacement of the inner member.

5. The damper for a rotating machine according to claim 1, wherein: The inner member and the outer member are cylindrical.

6. The damper for a rotating machine according to claim 1, wherein: The magnet is magnetized so that both ends in the axial direction have magnetic poles different from each other. The one of the inner member and the outer member has an opposing portion that opposes the magnet in the axial direction.

7. The damper for a rotating machine according to claim 6, wherein: The rotating machine damper further includes another magnet fixed to the other of the inner member and the outer member and facing one of the inner member and the outer member with a gap therebetween. The other magnet is arranged on the opposite side of the opposing portion from the magnet in the axial direction and is opposed to the opposing portion in the axial direction. The magnet and the other magnet are both magnets of a Halbach array configured such that the magnetic flux density on the opposing portion side becomes higher.

8. The damper for a rotating machine according to claim 6, wherein: The rotating machine damper further comprises an auxiliary magnet. The auxiliary magnet is fixed to the other of the inner member and the outer member, is magnetized so that both ends in the radial direction have magnetic poles different from each other, and generates magnetic flux in a direction for strengthening the magnetic flux generated by the magnet.

9. The damper for a rotating machine according to claim 8, wherein: The magnet is a Halbach array magnet configured so that the magnetic flux density on the opposing portion side becomes higher. One of the inner member and the outer member has another opposing portion that opposes the magnet and the auxiliary magnet in the axial direction. The auxiliary magnet, together with the magnet, constitutes a magnet of a Halbach array configured such that the magnetic flux density on the other opposing portion side becomes higher.

10. The damper for a rotating machine according to claim 1, wherein: The other of the inner member and the outer member is a magnetic body also serving as a yoke.

11. A rotating machine comprising: The damper for a rotating machine according to any one of claims 1 to 10; a bearing supported by an inner member of the damper for a rotating machine; and A shaft is rotatably supported by the bearing.

12. The rotating machine according to claim 11, wherein The rotating machine comprises: a plurality of said dampers for the rotating machine; and a plurality of bearings corresponding to the plurality of the rotary machine dampers and respectively supported on inner side members of the corresponding rotary machine dampers; The shaft is rotatably supported by the plurality of bearings.

13. The rotating machine according to claim 11, wherein: The rotating machine is used in an extremely low temperature environment.

Images