JP2019100434A - Bearing device and rotary machine - Google Patents

Abstract

To detect stress applied to a squeeze film damper, to prevent damage due to fatigue.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; a plurality of elastic parts having an elastic member interposed between the inner ring and the outer ring, and provided discretely in a circumferential direction of the rotational shaft; and a strain gauge provided in the elastic member.SELECTED DRAWING: Figure 1

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 an oil film forming gap formed between an inner ring and an outer ring, and when the rotation shaft is vibrated and the gap is displaced, viscous incompressible oil is generated. There is disclosed a squeeze film damper which exerts an effect of damping vibration of a rotating shaft by flowing a gap.

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

  In the squeeze film damper, since the inner ring and the outer ring move relative to each other through the oil film forming gap, stress concentration is likely to occur, and it is conceivable that fatigue due to repeated stress may become a problem. Therefore, it is necessary to detect the stress generated at the place where fatigue is likely to occur and to prevent the occurrence of damage due to fatigue and the like in advance.

  An embodiment aims at detecting stress applied to a squeeze film damper and preventing damage due to fatigue and the like in advance.

(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 plurality of elastic portions discretely provided in the circumferential direction of the rotation shaft, including an elastic member interposed between the inner ring and the outer ring;
A strain gauge provided on the elastic member;
Equipped with

In the configuration of the above (1), since the elastic portion is provided between the inner ring and the outer ring, the relative displacement between the inner ring and the outer ring can be increased, thereby enhancing the damping effect of the oil flow. Can.
Further, by detecting the deformation of the elastic member constituting the elastic portion with the strain gauge, it is possible to grasp the load applied to the bearing portion from the rotation shaft. From these detected values, it is possible to grasp early whether or not an abnormality occurs in the rotating shaft system or the bearing portion, and by analyzing the detected values, it is possible to estimate the cause of the abnormality.

  Further, by providing the elastic portion, the rigidity of the squeeze film damper can be determined by the rigidity of the elastic portion. Therefore, since the stiffness and damping performance of the squeeze film damper can be selected independently of each other, optimal settings can be made for enhancing the damping effect.

(2) In one embodiment, in the configuration of (1),
The elastic portion is disposed to extend in the axial direction of the rotation axis.
According to the configuration of (2), the elastic portion can support the rotation shaft with an equal elastic force in the axial direction of the rotation shaft (hereinafter, also simply referred to as the “axial direction”).

(3) In one embodiment, in the configuration of (1) or (2),
The strain gauge is attached to a portion of the elastic member which is deformed by a load applied from the rotation shaft.
According to the configuration of (3), since the strain gauge is attached to a portion of the elastic member which is deformed by the load applied from the rotation shaft, the load applied to the bearing portion by detecting the deformation of the portion by the strain gauge Can be detected. Preferably, by attaching a strain gauge to a portion where deformation is large, it is possible to obtain a detection signal having a high SN ratio and less noise.

(4) In one embodiment, in the configuration of (1) or (2),
The strain gauge is attached to an axial end face of the rotation shaft in the elastic member.
According to the configuration of the above (4), the strain gauge can be easily attached by attaching the strain gauge to the axial end face of the rotary shaft that can be easily attached.

(5) In one embodiment, in any one of the configurations (1) to (4),
The strain gauges are respectively attached to different positions of the elastic member in the axial direction of the rotation shaft.
According to the configuration of the above (5), the strain gauge can be attached at different positions in the axial direction of the rotary shaft among the elastic members, and the inclination in the axial direction of the rotary shaft can be grasped by comparing the respective detection values. The level adjustment of the rotation axis becomes possible. Preferably, the detection accuracy can be enhanced by respectively attaching the sensor to or in the vicinity of both axial end surfaces of the rotation shaft and comparing respective detection values.

(6) In one embodiment, in any one of the configurations (1) to (5),
The strain gauges are attached to each of the elastic portions at point-symmetrical positions with respect to the rotation axis.
According to the configuration of the above (6), by comparing the obtained detection values, it is possible to detect the bias of the load applied from the rotating shaft, and the detection values of this can be utilized for abnormality determination of the bearing portion and the squeeze film damper.

(7) In one embodiment, in any one of the configurations (1) to (6),
The strain gauges are attached to each of the elastic portions adjacent to each other in the circumferential direction.
According to the configuration of the above (7), by attaching the strain gauge to each of the elastic portions adjacent to each other in the circumferential direction, it is possible to detect the deviation of the load applied from the rotating shaft, and detect the detected value of the bearing or squeeze film damper Can be used to determine the abnormality of the

(8) In one embodiment, in any one of the configurations (1) to (7),
The elastic member is formed of an elastic rod-like body having a square cross section,
The strain gauge is located on a surface of the elastic rod-like body which is not in contact with the inner ring and the outer ring.
According to the configuration of the above (8), by attaching the strain gauge to the elastic rod-like body and to the portion where the deformation is large, it is possible to obtain a detection signal having a high SN ratio and less noise. Moreover, since the said site | part is not in contact with inner ringing or outer ringing, it can suppress that the disturbance by a hit etc. enters into a detected value.

(9) In one embodiment, in any one of the configurations (1) to (7),
The elastic member is constituted by an elastic rod-like body having a circular or elliptical cross section,
The strain gauge is attached to the outer peripheral surface of the elastic rod at a position not in contact with the inner ring and the outer ring.
According to the configuration of the above (9), by attaching the strain gauge to the elastic rod-like body and to a portion where the deformation is large, it is possible to obtain a detection signal having a high SN ratio and less noise. Moreover, since the said site | part is not in contact with inner ringing or outer ringing, it can suppress that the disturbance by a hit etc. enters into a detected value.

(10) In one embodiment, in any one of the configurations (1) to (7),
The elastic member is formed of an elastic body in which an elastic body having a shape of a truncated cone in cross section is laminated in two sheets so that the center has a small diameter,
The strain gauge is attached to the outer peripheral surface of the elastic body located between the inner ring and the outer ring.
According to the configuration of the above (10), by attaching the strain gauge to a portion which is not in contact with the inner ring or the outer ring, it is possible to obtain a detection signal having a high SN ratio and less noise. Further, since the strain gauge is attached to the outer surface of the elastic body located between the inner ring and the outer ring and is not in contact with the inner ring or the outer ring, a disturbance due to a jam or the like may be introduced into the detected value. It can be suppressed.

(11) In one embodiment, in any one of the configurations (1) to (7),
The elastic member is constituted by a coil spring,
The strain gauge is attached to the coil spring located between the inner ring and the outer ring.
According to the configuration of the above (11), by attaching the strain gauge to a portion where deformation is large, it is possible to obtain a detection signal having a high SN ratio and less noise. In addition, since the strain gauge is located between the inner ring and the outer ring and is not in contact with the inner ring or the outer ring, the detection value can be prevented from being disturbed by a disturbance or the like.

(12) In one embodiment, in any one of the configurations (1) to (7),
The elastic member is made of an elastic body having an S-shaped cross section,
The strain gauge is attached to an outer surface of the elastic body located between the inner ring and the outer ring.
According to the configuration of the above (12), by attaching the strain gauge to a portion where deformation is large, it is possible to obtain a detection signal having a high SN ratio and less noise. The strain gauge is located between the inner ring and the outer ring and is not in contact with the inner ring or the outer ring, so that it is possible to suppress the disturbance due to the detection value and the like from entering.

(13) In one embodiment, in any one of the configurations (1) to (7),
The elastic member is made of an elastic body having a zigzag shape in cross section,
The strain gauge is attached to an outer surface with respect to a center of curvature of a bending portion between the inner ring and the outer ring.
According to the configuration of the above (13), by attaching the strain gauge to a portion where deformation is large, it is possible to obtain a detection signal having a high SN ratio and less noise.

(14) The rotary machine according to one embodiment
The rotation axis,
A bearing device having the configuration of any one of the above (1) to (13);
Equipped with
According to the configuration of the above (14), since the elastic portion is present between the inner ring and the outer ring, the damping effect can be enhanced. Further, by detecting the deformation of the elastic member constituting the elastic portion with a strain gauge, it is possible to grasp the load applied to the bearing portion from the rotary shaft, and from this detection value, the occurrence of abnormality in the rotary shaft system or the bearing portion can be made early. While being able to grasp, it is also possible to estimate the cause of abnormality by analyzing the detection value.

  According to some embodiments, the load applied to the bearing portion can be grasped by detecting the deformation due to the load transmitted from the rotation shaft with the strain gauge. From this detection value, it is possible to grasp early whether or not an abnormality occurs in the rotary shaft system or the bearing portion, and by analyzing the detection value, it is possible to estimate the cause of the abnormality occurrence.

It is a sectional view which meets a radial direction of a bearing device concerning one embodiment. It is a sectional view which meets an axial direction of a bearing device concerning one embodiment. (A) And (B) is a sectional view in alignment with a radial direction of a part of bearing apparatus concerning some embodiments. (A) And (B) is a sectional view in alignment with a radial direction of a part of bearing apparatus concerning some embodiments. (A)-(F) are sectional drawings in alignment with radial direction of a part of bearing apparatus which concerns on some embodiment.

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 and 2 show a bearing device 10 according to one embodiment. 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. A plurality of elastic portions 22 (22A, 22B, 22C, 22D) are discretely provided in the circumferential direction between the inner ring 18 and the outer ring 20, and the elastic portion 22 has an elastic member 26, as shown in FIG. As shown at 5, a strain gauge 28 is attached to the elastic member 26.
Note that the arrow b direction in FIG. 1 indicates the radial direction of the rotary shaft 12 (hereinafter, also simply referred to as “radial direction”), and the arrow a direction in FIG.

  In the above configuration, oil is supplied from the oil supply portion (not shown) to the oil film forming gap S, and the incompressible oil having viscosity is made to flow in the oil film forming gap S, thereby damping the load applied from the rotating shaft 12 Damping effect can be obtained. 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. In addition, the oil film pressure in the oil film formation gap S can be adjusted by adjusting the flow amount of oil, whereby the damping performance can be adjusted.

The inner ring 18 and the outer ring 20 are relatively displaced via the elastic portion 22. The elastic member 26 is deformed in accordance with the relative displacement. The presence of the elastic portion 22 between the inner ring 18 and the outer ring 20 makes it possible to increase the relative displacement between the inner ring 18 and the outer ring 20, thereby enhancing the damping effect of oil flow. The load applied to the bearing portion 14 can be grasped by detecting the deformation of the elastic member 26 with the strain gauge 28. From these detected values, it is possible to grasp early whether or not an abnormality occurs in the rotary shaft system or the bearing portion 14. Also, by analyzing the detected values, it is possible to estimate the cause of the abnormality.
In one embodiment, the detection value detected by the strain gauge 28 is taken out by wire (not shown) or wirelessly.

  Further, 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 stiffness and damping performance of the squeeze film damper 16 can be set independently of each other, optimal settings can be made for enhancing the damping effect.

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減衰係数Ｃψが大きくなり、かつ減衰係数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１０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、減衰係数Ｃψが増加して減衰効果が増す。 The damping coefficient 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 equation (1), it can be seen that the damping coefficient Cψ increases as the area of the oil film formation gap increases, and the damping coefficient 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 10 increases and the oil film forming gap S narrows, the oil film pressure increases, the damping coefficient Cψ increases, and the damping effect increases.

  In one embodiment, as shown in FIG. 2, side plates 21 are provided on both axial end surfaces of the squeeze film damper 16. The side plate 21 forms an oil discharge path Pd that communicates with the oil film formation gap S with the both axial end surfaces of the outer ring 20. By discharging the oil from the oil discharge path Pd, it is possible to maintain the flowing state of the oil in the oil film formation gap S, and to damp the load applied from the rotating 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. Further, by adjusting the oil discharge amount from the oil discharge path Pd, the oil film pressure of the oil film formation gap S can be adjusted, whereby the damping performance can be adjusted.

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, the elastic portions 22 extend until they reach approximately the axial end faces of the squeeze film damper 16.

  In one embodiment, as shown in FIG. 1, the oil film forming gap S has an arc shape centered on the central axis O of the rotating shaft 12 in the radial direction cross section of the bearing device 10.

  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.

  In one embodiment, the bearing portion 14 includes rolling bearings instead of 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 rolling bearing, and the rotary 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.

Figures 3 and 4 illustrate elastics 22 (22a, 22b, 22c, 22d) according to some embodiments.
In the elastic portion 22 (22a, 22b) shown in FIG. 3, the strain gauge 28 is attached to a portion of the elastic member 26 (26a) that is deformed by a load applied from the rotary shaft 12.
According to this embodiment, the load applied to the bearing portion 14 can be detected by detecting the deformation of the elastic member 26 to which the strain gauge 28 is attached using the strain gauge 28. Preferably, by mounting the strain gauge 28 at a portion where the deformation is particularly large, it is possible to obtain a detection signal having a high SN ratio and less noise.

In one embodiment, in the elastic portion 22 (22c, 22d) shown in FIG. 4, the strain gauges 28 are attached to the axial end face of the rotary shaft 12 among the elastic members 26 (26a).
According to this embodiment, the strain gauge 28 can be easily attached by attaching the strain gauge 28 to the axial end face of the elastic member 26 (26a) that can be easily attached.

The elastic part 22 according to the embodiment shown in FIGS. 3 and 4, the elastic member 26 (26a) has an S-shaped cross-section partitioned by the oil film forming space S and the space _{S 0,} both ends of the elastic member 26 (26a) Are integrally connected to the inner ring 18 and the outer ring 20.
In the elastic portion 22 (22a) according to the embodiment shown in FIG. 3A, the strain gauge 28 is deformed by the load L applied from the rotary shaft 12 with respect to the center of curvature D at the curved portion 27a. Is attached to the large part).
In the elastic portion 22 (22b) according to the embodiment shown in FIG. 3 (B), the strain gauge 28 is a wall surface which forms the tip of the inner ring side oil film forming gap S, and is radial added from the rotary shaft 12 The load L is attached to the bent portion 27b which is largely deformed.

In one embodiment, as shown in FIG. 2, the strain gauges 28 are respectively attached to two or more different positions of the elastic member 26 in the axial direction of the rotation shaft 12.
According to this embodiment, the strain gauge 28 is attached to two or more different positions in the axial direction of the elastic member 26, and the detected inclinations of the rotary shaft 12 can be grasped by comparing the detected values with each other. By this, the level adjustment of the rotating shaft 12 becomes possible.
Preferably, the elastic member 26 is attached to the axial end faces of the rotary shaft 12 of the elastic member 26 or to two places in the vicinity thereof. Thus, the detection accuracy of the inclination in the axial direction of the rotation shaft 12 can be enhanced.

In one embodiment, as shown in FIG. 1, strain gauges 28 are attached to each of the elastic portions 22 that are point-symmetrical to each other with respect to the rotation axis 12. For example, the elastic portion 22 (22A) and the elastic portion 22 (22C) located at point-symmetrical positions with each other, or the elastic portion 22 (22B) and the elastic portion 22 (22D) located at point-symmetrical positions with each other.
According to this embodiment, it is possible to detect the bias of the load applied from the rotating shaft 12 by comparing the detection values obtained by the respective elastic portions 22, and these detection values may be used as an abnormality of the bearing portion 14 or the squeeze film damper 16. It can be used for judgment.

In one embodiment, as shown in FIG. 1, the strain gauges 28 are attached to each of the elastic portions 22 adjacent to each other in the circumferential direction of the rotation shaft 12. For example, the elastic portion 22 (22A) and the elastic portion 22 (22B) adjacent to each other, or the elastic portion 22 (22C) and the elastic portion 22 (22D) adjacent to each other are attached.
According to this embodiment, it is possible to detect the deviation of the load applied from the rotating shaft 12, and the detected value of this can be used for abnormality determination of the bearing portion 14 and the squeeze film damper 16.

In one embodiment, as shown in FIG. 5, the elastic part 22 is configured by the elastic member 26 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. In one embodiment, the space S ₀ has a square cross section.
FIG. 5 shows some embodiments of the elastic portion 22. FIG.

In one embodiment, in the elastic portion 22 (22e) shown in FIG. 5A, the elastic member 26 (26e) is formed of an elastic rod-like member having a square cross section, and the strain gauge 28 is an inner ring 18 in the elastic rod-like member. And the outer peripheral surface of a portion not in contact with the outer ring 20.
According to this embodiment, by attaching the strain gauge 28 to the portion where the deformation is large, it is possible to obtain a detection signal having a high SN ratio and less noise. Further, since the strain gauges 28 are not in contact with the inner ring 18 or the outer ring 20, it is possible to suppress the disturbance due to the jamming or the like from being detected.

  In one embodiment, the strain gauges 28 are attached to the central position of the outer peripheral surface, which is particularly large in deformation. This makes it possible to obtain a detection signal having a high SN ratio and less noise.

In one embodiment, one of the elastic rod-like body long extends in the axial direction of the space S ₀ are accommodated in the space S ₀ as the elastic member 26 (26e).

In one embodiment, the elastic portion 22 (22f) shown in FIG. 5 (B) is formed of an elastic rod having an elastic member 26 (26f) having a circular or elliptical cross section, and the strain gauge 28 has an inner ring 18 And the outer peripheral surface of the elastic rod at a position not in contact with the outer ring 20.
According to this embodiment, by attaching the strain gauge 28 to a portion where deformation is large, it is possible to obtain a detection signal having a high SN ratio and less noise. Further, since the strain gauges 28 are not in contact with the inner ring 18 or the outer ring 20, it is possible to suppress the disturbance due to the jamming or the like from being detected.

In one embodiment, one of the elastic rod-like body long extends in the axial direction of the space S ₀ are accommodated in the space S ₀ as the elastic member 26 (26f).

In one embodiment, the elastic portion 22 (22g) shown in FIG. 5 (C) has an elastic member 26 (26g) having a cross section of a truncated cone shape (so-called disc spring shape) such that the center has a small diameter. The strain gauges 28 are attached to the outer peripheral surface of the elastic body located between the inner ring 18 and the outer ring 20.
According to this embodiment, by attaching the strain gauge 28 to the portion where the deformation is large, it is possible to obtain a detection signal having a high SN ratio and less noise. Further, the strain gauge 28 is attached to the outer peripheral surface of the elastic body located between the inner ring 18 and the outer ring 20 and is not in contact with the inner ring 18 or the outer ring 20. Can be suppressed.
In one embodiment, the elastic member 26 (26g) is configured to be solid or hollow.

  In one embodiment, one rod-like elastic member 26 (26g) extends along the axial direction. In another embodiment, a plurality of elastic members 26 (26g) are discretely arranged in the axial direction.

In one embodiment, the elastic members 26 (26e, 26f, 26g) configured by one member are disposed substantially in the entire axial region of the squeeze film damper 16.
In one embodiment, the elastic members 26 (26e-26g) are made of elastic rubber.
The elastic member 26 consists of a single member elongated (26e~26g) is easily accommodated in the space _{S 0.}

In one embodiment, as shown in FIG. 5D, the elastic member 26 (26h) is formed of a coil spring, and the strain gauge 28 is attached to the surface of the coil spring located between the inner ring 18 and the outer ring 20. Be
According to this embodiment, by mounting the strain gauge 28 on the surface of the coil spring with a large amount of deformation, it is possible to obtain a detection signal having a high SN ratio and a small amount of noise. Further, the strain gauge 28 is attached at a position not in contact with the inner ring 18 or the outer ring 20 on the surface of the coil spring, so that it is possible to suppress the disturbance due to the detection value or the like from entering.

In one embodiment, a plurality of coil springs are accommodated in the space S ₀ and discretely disposed in the axial direction of the rotation shaft 12.

In one embodiment, as shown in FIG. 5 (E), the elastic member 26 (26i) is formed of an elastic body having an S-shaped cross section, and the strain gauges 28 include the inner ring 18 and the outer ring 20. It is attached to the outer surface of the said elastic body located between.
According to this embodiment, by attaching the strain gauge 28 to a portion where deformation is large, it is possible to obtain a detection signal having a high SN ratio and less noise. In addition, since the strain gauge 28 is located between the inner ring 18 and the outer ring 20 and not in contact with the inner ring 18 or the outer ring 20, the detection value can be prevented from being disturbed by a disturbance or the like.

In one embodiment, one elastic member 26 (26i) is elongated in the axial direction in the space S ₀ as one long elastic member. In another embodiment, a plurality of the elastic bodies are discretely arranged in the space S ₀ in the axial direction.

In one embodiment, as shown in FIG. 5 (F), the elastic member 26 (26j) is formed of an elastic body having a zigzag shape in cross section, and the strain gauge 28 is between the inner ring 18 and the outer ring 20. And is attached to the outside surface with respect to the center of curvature D of the bending portion.
According to this embodiment, by attaching the strain gauge 28 to the portion where the deformation is large, it is possible to obtain a detection signal having a high SN ratio and less noise.
In one embodiment, one elongated elastic body is axially extended in the space S ₀ . In another embodiment, a plurality of the elastic bodies are discretely arranged in the space S ₀ in the axial direction.

  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.

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, since the elastic portion 22 is present between the inner ring 18 and the outer ring 20, the damping effect can be enhanced. Further, by detecting the deformation of the elastic member 26 constituting the elastic portion 22 with the strain gauge 28, the load applied from the rotary shaft 12 to the bearing portion 14 can be grasped, and the abnormality of the rotary shaft system or the bearing device 10 from this detection value. While the presence or absence can be grasped | ascertained early, the cause of abnormality generation can also be estimated by analyzing a detected value.

  According to some embodiments, by detecting the stress applied to the squeeze film damper and analyzing the detected value, it is possible to prevent damage due to fatigue etc. in advance, for example, a rotary machine such as a compressor or a steam turbine Applicable to

DESCRIPTION OF SYMBOLS 10 bearing apparatus 12 rotating shaft 14 bearing part 16 squeeze film damper 18 inner ring 20 outer ring 21 side plate 22 (22A, 22B, 22C, 22D, 22a, 22b, 22c, 22d, 22e, 22f, 22g, 22h, 22i, 22j) Elastic portion 24 Tilting pad 25 Pivot 26 (26a, 26e, 26f, 26g, 26h, 26i, 26j) Elastic member
27a, 27b Curved portion 28 Strain gauge Pd oil discharge path S Oil film formation gap So space

Claims (14)

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 plurality of elastic portions discretely provided in the circumferential direction of the rotation shaft, including an elastic member interposed between the inner ring and the outer ring;
A strain gauge provided on the elastic member;
A bearing device comprising:   The bearing device according to claim 1, wherein the elastic portion is disposed to extend in the axial direction of the rotation shaft.   The bearing device according to claim 1, wherein the strain gauge is attached to a portion of the elastic member which is deformed by a load applied from the rotating shaft.   The bearing device according to claim 1, wherein the strain gauge is attached to an axial end surface of the rotation shaft among the elastic members.   The bearing device according to any one of claims 1 to 4, wherein the strain gauges are attached at different positions in the axial direction of the rotation shaft among the elastic members.   The bearing device according to any one of claims 1 to 5, wherein the strain gauge is attached to each of the elastic portions located at point-symmetrical positions with respect to the rotation axis.   The bearing device according to any one of claims 1 to 6, wherein the strain gauge is attached to each of the elastic portions adjacent to each other in the circumferential direction. The elastic member is formed of an elastic rod-like body having a square cross section,
The bearing device according to any one of claims 1 to 7, wherein the strain gauge is located on a surface of the elastic rod-like body which is not in contact with the inner ring and the outer ring. The elastic member is constituted by an elastic rod-like body having a circular or elliptical cross section,
The bearing device according to any one of claims 1 to 7, wherein the strain gauge is attached to the outer peripheral surface of the elastic rod at a position not in contact with the inner ring and the outer ring. The elastic member is formed of an elastic body in which an elastic body having a shape of a truncated cone in cross section is laminated in two sheets so that the center has a small diameter,
The bearing device according to any one of claims 1 to 7, wherein the strain gauge is attached to an outer peripheral surface of the elastic body located between the inner ring and the outer ring. The elastic member is constituted by a coil spring,
The bearing device according to any one of claims 1 to 7, wherein the strain gauge is attached to the coil spring located between the inner ring and the outer ring. The elastic member is made of an elastic body having an S-shaped cross section,
The bearing device according to any one of claims 1 to 7, wherein the strain gauge is attached to an outer surface of the elastic body located between the inner ring and the outer ring. The elastic member is made of an elastic body having a zigzag shape in cross section,
The bearing device according to any one of claims 1 to 7, wherein the strain gauge is attached to an outer side surface with respect to a center of curvature of a bending portion between the inner ring and the outer ring. The rotation axis,
The bearing device according to any one of claims 1 to 13,
A rotary machine comprising:

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