JP2019100414A - Bearing device and rotary machine - Google Patents

Abstract

To improve attenuation effect of a squeeze film damper to a rotational shaft system, in a bearing device rotatably supporting the rotational shaft system and comprising the squeeze film damper.SOLUTION: A bearing device comprises: a bearing part for rotatably supporting a rotational shaft; a squeeze film damper provided on an outer peripheral side of the bearing part, and having an inner ring and an outer ring opposite to each other with at least one oil film formation interval held therebetween; and a side plate provided on axial both end surfaces of the squeeze film damper, and forming an oil discharge passage communicating with the oil film formation interval between axial both end surfaces of the outer ring. The oil discharge passage has a narrow part.SELECTED DRAWING: Figure 2

Description

  The present disclosure relates to a bearing device and a rotary machine including the bearing device.

In rotary machines such as compressors and steam turbines, stable support of the rotary shaft system is one of the problems. In order to solve this problem, it is effective to improve the support characteristics (attenuation, rigidity, etc.) of the bearing portion that supports the rotating shaft, and studies from this point of view have been made.
In Patent Document 1, oil is supplied to a gap formed between an inner ring and an outer ring, and when the above gap is displaced according to a load applied from a rotating shaft, it is viscous and incompressible. There is disclosed a squeeze film damper which produces an effect of damping vibration or the like of a rotating shaft by oil flowing in the gap.

U.S. Pat. No. 5,421,655

  In the squeeze film damper, the damping effect on the vibration of the rotating shaft differs depending on the amount of oil discharged from the oil film forming gap. At present, the configuration of the oil discharger for enhancing the damping effect has not been studied in detail, and therefore, the damping effect can not be obtained more than a certain level.

  One embodiment aims to improve the damping effect of a squeeze film damper on a rotating shaft system in a bearing device that rotatably supports the rotating shaft system and includes a squeeze film damper.

(1) The bearing device according to one embodiment
A bearing for rotatably supporting the rotating shaft;
A squeeze film damper including an inner ring and an outer ring provided on an outer peripheral side of the bearing portion and facing each other across at least one oil film formation gap;
A side plate which is provided on both axial end surfaces of the squeeze film damper and which forms an oil discharge passage communicating with the oil film forming gap between the axial end surfaces of the outer ring;
Equipped with
The oil discharge passage has a throttling portion.

According to the configuration of the above (1), since the oil discharge passage formed by the side plate has the narrowed portion, the oil film pressure in the oil film forming gap with respect to the load of the rotating shaft applied to the bearing can be increased. Since the increase in oil film pressure is in a relationship equivalent to the decrease in oil film formation gap, the damping effect of the squeeze film damper can be improved. By this, the vibration etc. which generate | occur | produce in a rotating shaft system can be suppressed, and a rotating shaft system can be supported stably.
Further, since the oil discharge path is formed between the axial end face of the outer ring and the side plate, the throttling portion can be formed without restricting the movement of the inner ring following the movement of the rotary shaft system.

(2) In one embodiment, in the configuration of (1),
The throttling portion is configured of a seal ring provided in the oil discharge path.
According to the configuration of the above (2), since the throttling portion is formed by the seal ring, the throttling portion can be formed with a simple configuration without constraining the movement of the inner ring following the motion of the rotary shaft system.

(3) In one embodiment, in the configuration of (2),
The seal ring is accommodated in a recess formed in a wall surface forming the oil discharge path of the side plate.
According to the configuration of the above (3), the seal ring is fixed to the side plate and follows the movement of the side plate. Therefore, the throttling function of the throttling portion can be maintained.

(4) In one embodiment, in the configuration of the above (2) or (3),
The seal ring is made of an elastic body.
According to the configuration of the above (4), since the seal ring is made of an elastic body, the robustness is obtained and the clearance management of the narrowed portion becomes easy. Even if the gap in the throttling portion is closed, oil can be discharged from the throttling portion by the oil film pressure in the oil film forming gap, and the oil fluidity of the oil film forming gap can be maintained.

(5) In one embodiment, in any one of the configurations (1) to (4),
A piezoelectric element provided between the side plate and both axial end faces of the inner ring;
The piezoelectric element is configured to be capable of adjusting the throttling degree of the throttling portion by moving the side plate in the axial direction of the inner ring with respect to the inner ring.
Since the piezoelectric element is displaced when a voltage is applied, the distance between the side plate and both axial end faces of the inner ring can be adjusted.
According to the configuration of the above (5), by providing the piezoelectric element, it is possible to adjust the clearance of the throttling portion, to obtain robustness and to facilitate the management of the clearance of the throttling portion.

(6) In one embodiment, in any one of the configurations (1) to (5),
The side plates are fixed to both axial end faces of the inner ring,
A sensor capable of detecting the vibration level of the rotating shaft;
A frequency analyzer for frequency analysis of the vibration level detected by the sensor;
Equipped with
When the vibration frequency obtained by the frequency analyzer includes the vibration frequency other than the multiple of the rotation frequency of the rotation axis, it is determined that the function of the squeeze film damper is abnormal.

  According to the configuration of (6), when the vibration frequency obtained by the frequency analyzer includes a vibration frequency different from the rotation frequency of the rotation shaft and its multiple, the inner ring movement follows the load applied from the rotation shaft It shows that you are not. As a cause of this, it is presumed that the inner ring and outer ring in the constriction portion are bitten by each other and some other functional failure has occurred.

(7) In one embodiment, in the configuration of (6),
An elastic portion discretely provided in the circumferential direction between the inner ring and the outer ring;
The sensor is constituted by a strain gauge provided in the elastic portion.
The strain detected by the strain gauge is generated by the movement of the inner ring. Therefore, the period and amplitude of this distortion reflect the innerring movement. Therefore, the frequency analysis of this distortion is performed, and it is shown that the inner ringing movement does not follow the load applied from the rotation axis when the rotation frequency of the rotation axis and the vibration frequency different from its multiple are included.

(8) In one embodiment, in the configuration of (6),
The sensor is constituted by an acceleration sensor provided in the inner ring.
According to the configuration of (8), by detecting the acceleration of the movement of the inner ring by the acceleration sensor, it can be determined whether the movement of the inner ring follows the load applied from the rotation axis. When not following, it can be estimated that some functional failure has occurred, such as biting into the outer ring surface of the diaphragm.

(9) In one embodiment, in any one of the configurations (1) to (8),
The wall surface of the side plate that forms the oil discharge path is formed to gradually approach the axially opposite end surfaces of the outer ring toward the outside.
The throttling portion is formed at an outer end of the wall surface.
According to the configuration of (9), the throttling portion can be formed with a simple configuration.

(10) In one embodiment, in any one of the configurations (1) to (9),
An elastic portion discretely provided in the circumferential direction is provided between the inner ring and the outer ring.
According to the structure of said (10), the rigidity of a squeeze film damper can be determined by the rigidity of the said elastic part by providing the said elastic part. Therefore, since the stiffness and damping performance of the squeeze film damper can be set independently of each other, an optimal setting for increasing the damping effect is possible in each case.

(11) In one embodiment, in any one of the configurations (1) to (10),
The bearing portion includes a tilting pad.
According to the structure of said (11), the squeeze film damper of the said structure is provided in the outer peripheral side of the bearing part containing a tilting pad, and a rotating shaft can be supported by these combination. These combinations can stably support the rotating shaft. In addition, the rotation shaft can be stably rotated by the anti-seizure effect of the oil film formed around the tilting pad.

(12) In one embodiment, in any one of the configurations (1) to (10),
The bearing portion includes a rolling bearing.
According to the structure of said (12), the squeeze film damper of the said structure is provided in the outer peripheral side of the bearing part containing a rolling bearing, and a rotating shaft can be supported by these combination. By this, the synergetic effect of the low friction support by the bearing including the rolling bearing and the damping effect of the squeeze film damper, the damping effect of the vibration etc. generated in the rotating shaft system while securing the rigidity of the support side even at high speed rotation And can stably support the rotating shaft.

(13) The rotary machine according to one embodiment
The rotation axis,
A bearing device having any one of the configurations (1) to (12);
Equipped with
According to the configuration of the above (13), the damping effect of the squeeze film damper can be improved, whereby vibrations and the like generated in the rotary shaft system can be suppressed, and the rotary shaft system can be stably supported. Further, since the oil discharge path is formed between the axial end face of the outer ring and the side plate, the throttling portion can be formed without restricting the movement of the inner ring following the movement of the rotary shaft system.

  According to some embodiments, by providing the oil discharge passage configured as described above, the damping effect of the squeeze film damper can be enhanced.

It is radial sectional drawing of the bearing apparatus which concerns on one Embodiment. It is an axial sectional view of a part of bearing apparatus concerning one embodiment. It is an axial sectional view which expanded a part of bearing device concerning one embodiment. It is an axial sectional view of a part of bearing apparatus concerning one embodiment. It is an axial sectional view of a part of bearing apparatus concerning one embodiment. It is a block diagram which shows the abnormality determination part of the bearing apparatus which concerns on one Embodiment. (A)-(F) show the elastic part which concerns on some embodiment, (A) and (B) are sectional drawings, (C)-(F) are front views.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as the embodiments or shown in the drawings are not intended to limit the scope of the present invention to this, but are merely illustrative. Absent.
For example, a representation representing a relative or absolute arrangement such as “in a direction”, “along a direction”, “parallel”, “orthogonal”, “center”, “concentric” or “coaxial” is strictly Not only does it represent such an arrangement, but also represents a state of relative displacement with an angle or distance that allows the same function to be obtained.
Further, for example, the expression expressing a shape such as a quadrilateral shape or a cylindrical shape not only represents a shape such as a rectangular shape or a cylindrical shape in a geometrically strict sense, but also an uneven portion The shape including a chamfer etc. shall also be expressed.
On the other hand, the expressions "comprising", "having", "having", "including" or "having" one component are not exclusive expressions excluding the presence of other components.

1 to 7 show a bearing device 10 (10A, 10B, 10C) according to some embodiments.
In FIG. 1, the bearing device 10 includes a bearing portion 14 on the outer peripheral side of the rotating shaft 12 and a squeeze film damper 16 on the outer peripheral side of the bearing portion 14. The bearing portion 14 rotatably supports the rotating shaft 12. The squeeze film damper 16 has an inner ring 18 and an outer ring 20 which face each other across at least one oil film forming gap S.
As shown in FIGS. 2, 4 and 5, in the bearing device 10 (10A to 10C), the side plates 21 (21a, 21b, 21c) are provided on both axial end faces of the squeeze film damper 16 and the shaft of the outer ring 20 An oil discharge path Pd communicating with the oil film formation gap S is formed between the direction both end faces. The oil discharge path Pd has throttling portions 28 (28a, 28b, 28c).

  Here, the "axial direction" refers to the axial direction of the rotary shaft 12, refers to the direction of arrow a in FIG. 2, and the "radial direction" refers to the radial direction of the rotary shaft 12, and Arrow b direction.

According to the above configuration, oil is supplied from the oil supply portion (not shown) to the oil film forming gap S, and oil is discharged from the oil discharge passage Pd, so that incompressible oil having viscosity is flowed in the oil film forming gap S Let Thus, it is possible to obtain a damping effect for damping the load applied from the rotation shaft 12. Vibration and the like of the rotary shaft system are suppressed by this damping effect, and stable support of the rotary shaft system becomes possible.
Moreover, the oil film pressure of oil film formation clearance S with respect to the load of the rotating shaft added to the bearing part 14 can be increased by providing the aperture | diaphragm | squeeze part 28 (28a-28c). Since the increase of the oil film pressure is in a relationship equivalent to the decrease of the oil film formation gap S, the damping effect of the squeeze film damper 16 can be improved.

In addition, by adjusting the flow amount of oil at the throttling portion 28, the oil film pressure of the oil film formation gap S can be adjusted, whereby the damping performance can be adjusted.
Furthermore, since the oil discharge path Pd is formed between the axial direction end face of the outer ring 20 and the side plate 21, the throttling portion 28 is formed without constraining the movement of the inner ring 18 following the movement of the rotary shaft system. it can.

ここで、Ｂ＝１２πμＬ（Ｒ／ｃ）^３、μ：油の粘性係数、Ｒ：ダンパ径、Ｌ：ダンパ幅、ｃ：径方向隙間の大きさ、ε：回転軸の偏心量である。
ε＝ｅ／ｃ＝１−δ_０／ｃ
ここで、ｅ：回転軸の偏心量、δ_０：回転軸の軸受からの浮上量である。
（１）式から、油膜形成隙間の面積が大きいほど油膜減衰常数Ｃψが大きくなり、かつ油膜減衰常数Ｃψは径方向隙間の大きさｃの３乗に比例することがわかる。従って、回転軸１２から軸受装置に付加される圧力が大きくなり、油膜形成隙間Ｓが狭くなると、油膜圧が増加し、油膜減衰常数Ｃψが増加して減衰効果が増す。 The oil film damping constant Cψ representing the damping effect exerted by the oil film formation can be obtained from the following equation (1).

Here, B = 12πμL (R / c) ³ , μ: viscosity coefficient of oil, R: damper diameter, L: damper width, c: radial gap size, ε: eccentricity of the rotation axis.
ε = e / c = 1−δ ₀ / c
Here, e: eccentricity of the rotary shaft, δ ₀ : fly height from the bearing of the rotary shaft.
From the equation (1), it is understood that the oil film damping constant C 大 き く becomes larger as the area of the oil film forming gap is larger, and the oil film damping constant Cψ is proportional to the cube of the size c of the radial gap. Therefore, when the pressure applied from the rotary shaft 12 to the bearing device increases and the oil film forming gap S narrows, the oil film pressure increases, the oil film damping constant Cψ increases, and the damping effect increases.

  In one embodiment, as shown in FIG. 1, in the bearing device 10, a plurality of elastic portions 22 are provided discretely in the circumferential direction between the inner ring 18 and the outer ring 20. By providing the elastic portion 22, the rigidity of the squeeze film damper 16 can be determined by the rigidity of the elastic portion 22. Therefore, since the rigidity of the squeeze film damper 16 and the damping performance due to the oil film formation can be set independently of each other, optimal settings can be made for each in order to enhance the damping effect of the squeeze film damper 16.

  In one embodiment, the elastic portion 22 is disposed to extend in the axial direction of the rotation shaft 12. The disposition of the elastic portion 22 can exert equal elastic force in the axial direction of the rotary shaft 12, and can support the rotary shaft 12 with equal elastic force in the axial direction of the rotary shaft 12.

In one embodiment, as shown in FIG. 1, the bearing portion 14 includes a tilting pad 24. The tilting pad 24 is connected to the inner surface of the inner ring 18 via a pivot 25. The tilting pad 24 can be tilted in any direction with respect to the pivot 25. The tilting pad 24 is formed with a lubricating oil flow passage (not shown) opened on the inner side, and the lubricating oil is supplied between the rotating shaft 12 and the tilting pad 24.
According to this embodiment, the squeeze film damper 16 configured as described above is provided on the outer peripheral side of the bearing portion including the tilting pad 24, and the rotation shaft 12 can be supported by a combination of these. By this, the synergetic effect of the low friction support by the bearing portion including the rolling bearing and the damping effect of the squeeze film damper 16 attenuates the vibration etc. generated in the rotating shaft system while securing the rigidity on the support side even at high speed rotation. The effect can be enhanced, and the rotary shaft 12 can be stably supported.

  In one embodiment, the bearing portion 14 comprises a rolling bearing. According to this embodiment, the squeeze film damper 16 configured as described above is provided on the outer peripheral side of the bearing portion including the rolling bearing, and the rotation shaft can be supported by a combination of these. By this, the synergetic effect of the low friction support by the bearing portion including the rolling bearing and the damping effect of the squeeze film damper 16 attenuates the vibration etc. generated in the rotating shaft system while securing the rigidity on the support side even at high speed rotation. The effect can be enhanced, and the rotary shaft 12 can be stably supported.

In one embodiment, as shown in FIG. 2, the throttling portion 28 (28 a) of the bearing device 10 (10 A) is configured by a seal ring 30 provided in the oil discharge path Pd. The seal ring 30 is configured of, for example, an O-ring or a piston ring.
According to this embodiment, since the throttling portion 28 (28a) is formed by the seal ring 30, the throttling portion is formed with a simple configuration without restricting the movement of the inner ring 18 following the movement of the rotary shaft system. it can.

In one embodiment, the seal ring 30 is accommodated in a recess 32 formed in the wall of the side plate 21 (21a) forming the oil discharge path Pd.
According to this embodiment, the seal ring 30 is accommodated in the recess 32 and fixed to the side plate 21 (21a) to follow the movement of the side plate. Therefore, the diaphragm function of the diaphragm unit 28 (28a) can be maintained.

  In one embodiment, the seal ring 30 is comprised of an elastic body, such as elastic rubber. Since the seal ring 30 is made of an elastic body, robustness is obtained, and the clearance management of the narrowed portion 28 (28a) is facilitated. Even if the gap of the throttling portion 28 (28a) is closed, oil can be discharged from the throttling portion 28 (28a) by the oil film pressure of the oil film forming gap S, and the oil fluidity of the oil film forming gap S can be maintained.

In one embodiment, as shown in FIG. 4, piezoelectric elements 34 are provided between the side plates 21 (21 b) of the bearing device 10 (10 B) and both axial end faces of the inner ring 18. Since the piezoelectric element 34 is displaced when a voltage is applied, the distance between the side plate 21 (21 c) and both axial end surfaces of the outer ring 20 can be adjusted. The piezoelectric element 34 can adjust the throttling degree of the throttling portion 28 (28b) by moving the side plate 21 (21b) in the axial direction of the inner ring 18 with respect to the inner ring 18.
According to this embodiment, by providing the piezoelectric element 34, it is possible to adjust the gap of the diaphragm 28 (28b), obtain robustness, and facilitate the management of the gap of the diaphragm 28 (28b).

  In one embodiment, as shown in FIG. 4, the piezoelectric element 34 is formed in a plate-like body. By forming the piezoelectric element 34 in a plate-like body, the piezoelectric element 34 can be accommodated in a narrow space between the side plate 21 (21 b) and both axial end surfaces of the inner ring 18.

  In one embodiment, as shown in FIG. 4, the wall surface of the side plate 21 (21 b) facing the inner ring 18 is a flat projecting surface 36 a and a recessed surface 36 b that have steps and are disposed parallel to each other. Configured The narrowed portion 28 (28b) can be easily formed by the projecting surface 36a, and the space can be made compact by arranging the plate-like piezoelectric element 34 in the space formed by the recessed surface 36b.

  In one embodiment, as shown in FIG. 5, in the bearing device 10 (10C), the wall surface of the side plate 21 (21c) forming the oil discharge path Pd gradually approaches the axially opposite end surfaces of the outer ring 20 It is formed to The narrowed portion 28 (28c) portion is formed at the outer end of the side plate 21 (21c). According to this embodiment, the throttling portion can be formed with a simple configuration.

  In one embodiment, as shown in FIGS. 2, 4 and 5, the side plates 21 are fixed to both axial end faces of the inner ring 18. Then, as shown in FIG. 6, a sensor 38 (38a, 38b, 38c) capable of detecting the vibration level of the rotary shaft 12, and a frequency analyzer 40 for frequency analysis of the vibration level detected by the sensor Prepare. When the vibration frequency obtained by the frequency analyzer 40 includes the vibration frequency other than a multiple of the rotation frequency of the rotating shaft 12, it is determined that the function of the squeeze film damper 16 is abnormal.

  According to this embodiment, when the vibration frequency obtained by the frequency analyzer 40 includes a vibration frequency different from the rotation frequency of the rotation shaft 12 and its multiple, the movement of the inner ring 18 follows the load applied from the rotation shaft 12 It shows that you are not. As a cause of this, it is presumed that the inner ring 18 and the outer ring 20 in the throttle unit 28 bite each other and some other functional failure has occurred.

  In one embodiment, as shown in FIG. 6, the sensor 38 is configured by a strain gauge 38 (38 a) provided on the elastic portion 22. Since the strain detected by the strain gauge 38 (38 a) is generated by the movement of the inner ring 18, the period and amplitude of this strain reflect the movement of the inner ring 18. Therefore, the frequency analysis of this distortion is performed by the frequency analyzer 40, and the motion of the inner ring 18 does not follow the load applied from the rotation shaft 12 when the rotation frequency of the rotation shaft 12 and the vibration frequency different from its multiple are included. It is shown that.

  In one embodiment, as shown in FIG. 6, the cause is determined by the determination unit 42 from the result of the frequency analysis by the frequency analyzer 40, and the determination result is displayed on the display unit 44.

In one embodiment, as shown in FIG. 6, the sensor 38 is configured by an acceleration sensor 38 (38 b) provided on the inner ring 18.
According to this embodiment, the acceleration sensor 38 (38 b) detects the acceleration of the movement of the inner ring 18 to detect whether the movement of the inner ring 18 follows the load applied from the rotation shaft 12. When not following, it can be estimated that biting of the inner ring 18 and the outer ring 20 in the throttling unit 28 and any other functional problems have occurred.

  In one embodiment, as shown in FIG. 6, a sensor 38 is provided on the rotating shaft 12 and is configured of a vibration sensor 38 (38 c) that detects the vibration of the rotating shaft 12. The vibration sensor 38 (38c) detects the rotational frequency of the rotary shaft 12, and the motion of the inner ring 18 detected by the strain gauge 38 (38a) or the acceleration sensor 38 (38b) is analyzed by the frequency analyzer 40. When the movement of the inner ring 18 does not follow the load applied from the rotation shaft 12 when the movement of the inner ring 18 includes a vibration frequency different from the rotation frequency of the rotation shaft 12 and its multiple, the throttling portion It can be estimated that biting of the inner ring 18 and the outer ring 20 at 28 and some other functional problems have occurred.

  In one embodiment, when it is determined by the determination unit 42 that biting with the outer ring 20 occurs in the narrowed portion 28, the piezoelectric device 34 is operated in the bearing device 10 (10B) illustrated in FIG. By keeping 21 (21 b) away from the axial end face of the outer ring 20, the above-mentioned biting can be eliminated.

In one embodiment, as shown in FIG. 1, the elastic portion 22 is disposed in the gap between the inner ring 18 and the outer ring 20. In one embodiment, the resilient portion 22 is configured by an elastic member is accommodated in the space S ₀ which are discretely formed in the circumferential direction and communicates with the oil film clearance S. The space S ₀ extends along the axial direction, and the radial dimension of the space S ₀ is larger than the radial dimension of the oil film formation gap S or the special shape gap Sf. In one embodiment, the space S ₀ has a square cross section.
FIG. 7 shows several embodiments of the elastic portion 22. As shown in FIG.

Elastic part 22 shown in FIG. 7 (A) (22a), the cross section rectangular one elastic rod-like member 26a is accommodated in the space _{S 0,} extending in the axial direction.
Elastic part 22 shown in FIG. 7 (B) (22b) in cross section rectangular one elastic rod-like member 26b is accommodated in the space _{S 0,} extending in the axial direction.
Figure 7 (C) in the elastic part 22 shown (22c) is accommodated in the elastic body 26c is a space S ₀ of the elastic body center has two ply such that the diameter of the cross section disc spring shape (truncated cone shape) Be done. In one embodiment, one rod-like elastic body 26 c extends in the axial direction of the rotation shaft 12. In another embodiment, a plurality of elastic bodies 26c are discretely arranged in the axial direction. The elastic body may be hollow or solid.

In one embodiment, the elastic rod-shaped members 26 a and 26 b and the elastic body 26 c which are formed by one member are disposed substantially in the entire axial region of the squeeze film damper 16.
In one embodiment, the elastic bars 26a, 26b and the elastic body 26c are made of, for example, elastic rubber.
Elastic rod-like member 26a formed by a single member, 26b and the elastic member 26c is easily accommodated into the space _{S 0.}

Elastic part 22 shown in FIG. 7 (D) (22d) are discretely arranged a plurality of coil springs 26d in the axial direction of the rotary shaft 12 in the space _{S 0.}
Elastic part 22 shown in FIG. 7 (E) (22e) accommodates an elastic body 26e whose cross section has an S-shape in the space _{S 0.} In one embodiment, one elastic body 26 e is axially extended in the space S ₀ . In another embodiment, discretely arranged in the axial direction a plurality of elastic bodies 26e in the space S _0.
Elastic part 22 shown in FIG. 7 (F) (22f) accommodates an elastic body 26f which cross section is a zigzag shape in the space _{S 0.} In one embodiment, one elastic body 26 f is axially extended in the space S ₀ . In another embodiment, discretely arranged in the axial direction a plurality of elastic bodies 26f to the space S _0.
Here, the “zigzag shape” refers to a shape in which a plurality of straight line segments are continuously connected to each other at an end or a portion other than the end at an angle other than 180 degrees.

In one embodiment, the inner ring 18 and the outer ring 20 are integrally formed via the elastic portion 22. At this time, in one embodiment, the elastic portion 22 constitutes a spring member.
It should be noted that the sizes of the oil film forming gap S and the oil discharge path Pd shown in FIGS. 2 to 5 are exaggerated and illustrated, and in fact, a minute gap is formed.

A rotary machine according to an embodiment includes a rotating shaft 12 and a bearing device 10 having the above configuration.
According to this rotating machine, the damping effect of the squeeze film damper 16 can be improved, whereby vibrations and the like generated in the rotating shaft system can be suppressed, and the rotating shaft system can be stably supported. Further, since the oil discharge path Pd is formed between the axial end face of the outer ring 20 and the side plate 21, the throttling portion 28 is formed without constraining the movement of the inner ring 18 following the movement of the rotary shaft system. it can.

  According to some embodiments, in a bearing device including a squeeze film damper to rotatably support a rotating shaft system and a rotary machine including the bearing device, the rotating shaft is improved by improving the damping effect of the squeeze film damper. Vibration and the like generated in the system can be suppressed, and the rotary shaft can be stably supported. Therefore, it is suitably applied to rotary machines such as compressors and steam turbines.

Reference Signs List 10 (10A, 10B, 10C) Bearing device 12 Rotary shaft 14 Bearing 16 Squeeze film damper 18 Inner ring 20 Outer ring 21 (21a, 21b, 21c) Side plate 22 (22a, 22b, 22c, 22d, 22e, 22f) Elastic portion 24 Tilting pad 25 Pivot 26a, 26b Elastic rod 26c, 26e, 24f Elastic body 26d Coil spring 28 (28a, 28b, 28c) Throttle portion 30 Seal ring 32 Recess 34 Piezoelectric element 36a Protruding surface 36b Recessed surface 38 (38a , 38b, 38c) Sensor 38a Strain gauge 38b Acceleration sensor 38c Vibration sensor 40 Frequency analyzer 42 Judgment part 44 Display part Pd oil discharge path S Oil film formation gap S ₀ space

Claims (13)

A bearing for rotatably supporting the rotating shaft;
A squeeze film damper including an inner ring and an outer ring provided on an outer peripheral side of the bearing portion and facing each other across at least one oil film formation gap;
A side plate which is provided on both axial end surfaces of the squeeze film damper and which forms an oil discharge passage communicating with the oil film forming gap between the axial end surfaces of the outer ring;
Equipped with
The said oil discharge path has a constriction part, The bearing apparatus characterized by the above-mentioned.   The bearing device according to claim 1, wherein the throttling portion is configured by a seal ring provided in the oil discharge path.   The bearing device according to claim 2, wherein the seal ring is accommodated in a recess formed in a wall surface forming the oil discharge path of the side plate.   The bearing device according to claim 2, wherein the seal ring is made of an elastic body. A piezoelectric element provided between the side plate and both axial end faces of the inner ring;
5. The piezoelectric element according to claim 1, wherein the throttling degree of the throttling portion is adjustable by moving the side plate in the axial direction of the inner ring with respect to the inner ring. The bearing device according to any one of the preceding claims. The side plates are fixed to both axial end faces of the inner ring,
A sensor capable of detecting the vibration level of the rotating shaft;
A frequency analyzer for frequency analysis of the vibration level detected by the sensor;
Equipped with
It is determined that the function of the squeeze film damper is abnormal when the vibration frequency obtained by the frequency analyzer includes the vibration frequency other than a multiple of the rotation frequency of the rotation axis. The bearing device according to any one of 1 to 5. An elastic portion discretely provided in the circumferential direction between the inner ring and the outer ring;
The bearing device according to claim 6, wherein the sensor is constituted by a strain gauge provided in the elastic portion.   The bearing device according to claim 6, wherein the sensor is an acceleration sensor provided in the inner ring. The wall surface of the side plate that forms the oil discharge path is formed to gradually approach the axially opposite end surfaces of the outer ring toward the outside.
The bearing device according to any one of claims 1 to 8, wherein the narrowed portion is formed at an outer end of the wall surface.   The bearing device according to any one of claims 1 to 9, further comprising an elastic portion discretely provided in the circumferential direction between the inner ring and the outer ring.   The bearing device according to any one of claims 1 to 10, wherein the bearing portion includes a tilting pad.   The bearing device according to any one of claims 1 to 10, wherein the bearing portion includes a rolling bearing. The rotation axis,
A bearing device according to any one of the preceding claims,
A rotary machine comprising:

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