阅读说明：本技术 阻尼轴承及阻尼 (Damping bearing and damping ) 是由 石丸英嗣 武内辽太 于 2019-05-24 设计创作，主要内容包括：本发明具备：支持旋转轴的轴承部；和位于轴承部的外周,在半径方向上具有规定的厚度且外表面安装于结构部的筒状部；轴承部构成为在旋转轴之间形成规定的轴承间隙支持旋转轴的静压轴承构成；筒状部具有在外表面和内表面之间沿轴方向貫通,在周方向延伸的规定宽度的面状狭缝；面状狭缝在筒状部的周方向上隔开规定间隔地形成多个；多个面状狭缝形成为从筒状部的外表面的开放端沿半径方向延伸,在外表面和内表面之间圆弧状地延伸至周方向的规定位置；在没有面状狭缝的位置设置有从筒状部的外表面不通过面状狭缝地贯通轴承部的轴承流体供给孔。由此,构成可以用于小型机械的轴承,具有能衰减来自旋转轴的振动的阻尼功能的阻尼轴承。(The present invention is provided with: a bearing portion supporting the rotating shaft; and a cylindrical portion located on the outer periphery of the bearing portion, having a predetermined thickness in the radial direction, and having an outer surface attached to the structural portion; the bearing part is formed as a static pressure bearing which forms a specified bearing gap between the rotating shafts and supports the rotating shafts; the cylindrical portion has a planar slit of a predetermined width that penetrates in the axial direction between the outer surface and the inner surface and extends in the circumferential direction; a plurality of planar slits formed at predetermined intervals in the circumferential direction of the cylindrical portion; a plurality of planar slits formed to extend in a radial direction from an open end of an outer surface of the cylindrical portion and to extend in an arc shape to a predetermined position in a circumferential direction between the outer surface and the inner surface; a bearing fluid supply hole is provided at a position where the planar slit is not present, the bearing fluid supply hole penetrating the bearing portion from the outer surface of the cylindrical portion without passing through the planar slit. Thus, a bearing which can be used for a small machine and has a damping function of damping vibration from a rotating shaft is configured.)

1. A damping bearing is characterized in that,

the disclosed device is provided with:

a bearing portion supporting the rotating shaft; and

a cylindrical portion located on the outer periphery of the bearing portion, having a predetermined thickness in the radial direction, and having an outer surface attached to the structural portion;

the bearing portion is composed of a hydrostatic bearing which supports the rotating shaft with a predetermined bearing gap formed between the bearing portion and the rotating shaft;

the cylindrical portion has a planar slit of a predetermined width extending in a circumferential direction and passing through between an outer surface and an inner surface in an axial direction;

a plurality of the planar slits are formed at predetermined intervals in a circumferential direction of the cylindrical portion; a plurality of planar slits formed to extend in a radial direction from an open end of an outer surface of the cylindrical portion and to extend in an arc shape to a predetermined position in a circumferential direction between the outer surface and an inner surface; and a bearing fluid supply hole penetrating from the outer surface of the cylindrical portion to the bearing portion without passing through the planar slit is provided at a position where the planar slit is not present.

2. The damped bearing according to claim 1,

the cylindrical portion further includes an outer surface space on an outer surface outside the planar slit, and a damping fluid supply hole for supplying a damping fluid from the outer surface into at least one of the outer surface space and the planar slit.

3. The damped bearing according to claim 2,

the bearing fluid supply hole and the damping fluid supply hole are arranged in a staggered manner in the circumferential direction of the cylindrical portion;

a seal member is provided between the bearing fluid supply hole and the damping fluid supply hole, and the seal member prevents the damping fluid from being mixed into the bearing fluid supplied from the bearing fluid supply hole.

4. The damped bearing according to claim 1,

the cylindrical portion further includes an outer surface space on an outer surface outside the planar slit, and a solid damper element is provided in at least one of the outer surface space and the planar slit.

5. The damped bearing according to claim 4,

the cylindrical portion further includes holding members for preventing axial movement of the solid damper element at both axial end portions.

6. A damper, characterized in that,

is damping for damping vibration transmitted in a radial direction from the rotating shaft,

a cylindrical portion located on the outer periphery of the rotating shaft, having a predetermined thickness in the radial direction, and having an outer surface attached to the structural portion;

the cylindrical part has a planar slit with a fine width which penetrates between the outer surface and the inner surface along the axial direction and extends in the circumferential direction;

a plurality of the planar slits are formed at predetermined intervals in a circumferential direction of the cylindrical portion; a plurality of planar slits formed to extend in a radial direction from an open end of an outer surface of the cylindrical portion and to extend in an arc shape to a predetermined position in a circumferential direction between the outer surface and an inner surface;

the cylindrical portion further includes an outer surface space outside the planar slit, and a solid damper element is provided in at least one of the outer surface space and the planar slit.

7. The damper according to claim 6,

the cylindrical portion further includes holding members for preventing axial movement of the solid damper element at both axial end portions.

8. Damping according to claim 6 or 7,

the solid damping element is formed of a wire mesh to a prescribed thickness.

9. Damping according to claim 6 or 7,

the solid damping element is formed by bending a thin plate with a slit.

10. Damping according to claim 6 or 7,

the solid damping element is formed by collecting spherical particles.

Technical Field

The invention relates to a damping bearing with a damping function and damping.

Background

Conventionally, various bearings have been used to support various rotating shafts. The bearing includes a rolling bearing, a sliding bearing, a hydrostatic bearing, and the like. On the other hand, the rotating shaft generates excessive vibration under the inherent rotation speed range and load condition. Therefore, damping the vibration of the rotating shaft is necessary to improve the performance of the rotating machine.

As a prior art for suppressing excessive vibration, there is a technique of attenuating vibration by a part of a bearing. For example, a cylindrical damper element is provided at an outer peripheral portion of a rolling bearing, and damps radial vibration transmitted to the bearing (see, for example, patent documents 1 and 2). In these damper elements, a slit is formed between the inner surface and the outer surface of the tubular body, and a damping effect is exerted by a viscous fluid supplied to the inside of the slit.

Further, as another conventional technique, a damper bearing has been proposed. The damping bearing has a bearing supporting the rotating shaft, a centering spring for supporting the bearing with an appropriate rigidity, and damping for damping vibration. As a conventional technique of the damper bearing, for example, a damper bridge (damper bridge) is provided between an inner ring (rim) and an outer ring concentrically with an S-shaped centering spring interposed therebetween (see, for example, patent document 3). The damping bearing uses a gas bearing, and an integrated silk screen damper is arranged between an inner ring and an outer ring on both sides of a damping bridge.

Prior art documents:

patent documents:

patent document 1: japanese patent laid-open publication No. 2004-278580;

patent document 2: japanese patent laid-open publication No. 2007-56976;

patent document 3: U.S. Pat. No. 4, 2, 8083413B.

Disclosure of Invention

The problems to be solved by the invention are as follows:

further, a hydrostatic bearing is known as a bearing. Among the hydrostatic bearings, the gas bearing has an advantage that it can rotate at high speed with low friction and that it can render the bearing portion oil-free (oil-free) unlike oil-lubricated sliding bearings and rolling bearings. However, the gas bearing has a disadvantage of small vibration attenuation. In many high-speed rotating machines using gas bearings, they are small and are severely limited in space.

However, even if the gas bearing is combined with the damper element described in patent documents 1 and 2, the gas bearing cannot be used in combination with the gas bearing because the mechanism for supplying gas to the bearing portion and the mechanism for separating gas and viscous fluid are not disclosed in patent documents 1 and 2.

Further, in patent document 3, since the damper bridge is provided at the center portion in the axial direction of the bearing via the centering spring in the form of an S, the dimension in the radial direction is large, and it is difficult to adopt the bearing as a small machine. Further, the screen damper (damping element) cannot be disposed in the S-shaped centering spring portion, which has no damping effect and is therefore weak in damping.

Accordingly, an object of the present invention is to provide a damper bearing and damper having a damping function in which the bearing is a gas bearing, the radial dimension of the bearing can be reduced, and the entire axial direction can contribute to damping.

Means for solving the problems:

in order to achieve the above object, a damping bearing according to the present invention includes: a bearing portion supporting the rotating shaft; and a cylindrical portion located on the outer periphery of the bearing portion, having a predetermined thickness in the radial direction, and having an outer surface attached to the structural portion; the bearing portion is composed of a hydrostatic bearing which supports the rotating shaft with a predetermined bearing gap formed between the bearing portion and the rotating shaft, and the cylindrical portion has a planar slit with a predetermined width which penetrates through the outer surface and the inner surface in the axial direction and extends in the circumferential direction; a plurality of the planar slits are formed at predetermined intervals in a circumferential direction of the cylindrical portion; a plurality of planar slits formed to extend in a radial direction from an open end of an outer surface of the cylindrical portion and to extend in an arc shape to a predetermined position in a circumferential direction between the outer surface and an inner surface; and a bearing fluid supply hole penetrating from the outer surface of the cylindrical portion to the bearing portion without passing through the planar slit is provided at a position where the planar slit is not present.

According to this configuration, the bearing fluid can be appropriately supplied from the outer surface to the bearing portion through the partially provided bearing fluid supply hole that does not pass through the planar slit, and the function of the hydrostatic bearing can be exhibited. Therefore, the damper bearing can be configured to have a function of a hydrostatic bearing, and can damp vibration transmitted in the radial direction from the bearing portion in the entire axial direction by the plurality of planar slits extending in the circumferential direction between the outer surface and the inner surface of the cylindrical portion. Since the cylindrical portion includes the bearing portion, the radial dimension of the damper bearing having the damping function of the planar slit can be made small.

The cylindrical portion may further include an outer surface space on an outer surface outside the planar slit, and a damping fluid supply hole for supplying a damping fluid from the outer surface into at least one of the outer surface space and the planar slit.

With this configuration, by supplying the damping fluid from the damping fluid supply hole to at least one of the inside of the planar slit and the inside of the outer surface space, the radial vibration transmitted to the bearing portion can be appropriately damped by the damping effect of the damping fluid supplied to the inside of the planar slit or the inside of the outer surface space.

The bearing fluid supply hole and the damping fluid supply hole may be arranged to be shifted in a circumferential direction of the cylindrical portion; a seal member is provided between the bearing fluid supply hole and the damping fluid supply hole, and the seal member prevents the damping fluid from being mixed into the bearing fluid supplied from the bearing fluid supply hole.

With this configuration, the sealing member provided between the bearing fluid supply hole and the damping fluid supply hole arranged offset in the circumferential direction of the cylindrical portion can appropriately prevent the damping fluid from being mixed into the bearing fluid.

The cylindrical portion may further include an outer surface space on an outer surface outside the planar slit, and a solid damper element may be provided in at least one of the outer surface space and the planar slit. As the solid damper element, for example, a member formed by bending a thin plate with slits, a member formed by collecting resin spherical particles, or the like can be used.

In this configuration, the vibration can be damped by the solid damper element provided in at least one of the planar slit of the cylindrical portion and the outer surface space of the outer surface.

The cylindrical portion may further include holding members for preventing axial movement of the solid damper element at both axial ends.

In this configuration, the solid damper element disposed in the outer surface space provided on the outer surface of the cylindrical portion can be prevented from moving in the axial direction by the holding member. For example, even in the case where the solid damping element is spherical particles, stable position holding can be performed by the holding member.

On the other hand, the damper of the present invention is a damper for damping vibration transmitted in a radial direction from a rotating shaft, and includes a cylindrical portion located on an outer periphery of the rotating shaft, having a predetermined thickness in the radial direction, and having an outer surface attached to a structural portion; the cylindrical part has a planar slit with a fine width which penetrates between the outer surface and the inner surface along the axial direction and extends in the circumferential direction; a plurality of the planar slits are formed at predetermined intervals in a circumferential direction of the cylindrical portion; a plurality of planar slits formed to extend in a radial direction from an open end of an outer surface of the cylindrical portion and to extend in an arc shape to a predetermined position in a circumferential direction between the outer surface and an inner surface; the cylindrical portion further includes an outer surface space outside the planar slit, and a solid damper element is provided in at least one of the outer surface space and the planar slit.

According to this configuration, the solid damper element provided in at least one of the plurality of planar slits extending in the circumferential direction between the outer surface and the inner surface of the cylindrical portion and the outer surface space on the outer surface of the cylindrical portion can exert a damping function of damping vibration transmitted in the radial direction in the entire axial direction. Further, the damper can be configured to exhibit a high damping function by the solid damper element without using a damping fluid or the like.

The cylindrical portion may further include holding members for preventing axial movement of the solid damper element at both axial ends.

In this configuration, the solid damper element disposed in the outer surface space provided on the outer surface of the cylindrical portion can be prevented from moving in the axial direction by the holding member. For example, even in the case where the solid damping element is spherical particles, stable position holding can be performed by the holding member.

The solid damper element may be formed of a wire mesh to have a predetermined thickness. The vibration transmitted in the radial direction from the inner surface to the outer surface of the cylindrical portion can be damped by friction caused by deformation of the screen.

Further, the solid damper element may be formed by bending a thin plate with slits. This structure can attenuate vibration transmitted in the radial direction from the inner surface to the outer surface of the cylindrical portion by bending deformation of the slit portion.

Further, the solid damper element may be formed by collecting spherical particles. The vibration transmitted in the radial direction from the inner surface to the outer surface of the cylindrical portion can be damped by friction caused by the movement of the spherical particles.

The invention has the following effects:

according to the present invention, it is possible to provide a damper bearing which can exhibit a damping function by a planar slit provided in the entire axial direction of a cylindrical portion and can be used as a hydrostatic bearing by a bearing fluid flowing from a position where the planar slit does not extend in the circumferential direction of the cylindrical portion to a bearing portion.

Further, it is possible to provide damping in which vibration can be damped by the solid damping element in the entire axial direction.

Drawings

FIG. 1 is a front view showing a first damping bearing according to a first embodiment of the present invention;

FIG. 2 is a sectional view II-II of the first damping bearing shown in FIG. 1;

FIG. 3 is a front view showing a second damping bearing according to a second embodiment of the present invention;

FIG. 4 is a cross-sectional view IV-IV of the second damping bearing shown in FIG. 3;

FIG. 5 is a partial view showing a different example of the solid damping element shown in FIG. 3;

FIG. 6 is a top view of the solid damping element shown in FIG. 5;

FIG. 7 is a partial view showing another different example of the solid damping element shown in FIG. 3;

FIG. 8 is a front view showing a third damping bearing according to a third aspect of the present invention;

fig. 9 is a front view showing an example of providing a rolling bearing in the damper of the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the damper bearings 10 and 30 having the function of the hydrostatic bearing will be mainly described. The concept of the vertical and horizontal directions in the present specification and claims is the same as the concept of the vertical and horizontal directions in the state of facing the first damper bearing 10 shown in fig. 1. The direction perpendicular to the paper plane (the direction in which the rotating shaft 1 extends) of the first damper bearing 10 shown in fig. 1 is referred to as the axial direction. In addition, the gap and the like are exaggeratedly described.

(Structure of damping bearing according to first embodiment)

Fig. 1 is a front view showing a first damping bearing according to a first embodiment of the present invention. Fig. 2 is a sectional view II-II of the first damping bearing 10 shown in fig. 1. The first damper bearing 10 according to the first embodiment includes: a bearing portion 11 for supporting the rotary shaft 1; and a cylindrical portion 12 located on the outer periphery of the bearing portion 11 and attached to the structure portion 2 (a housing or the like). The bearing portion 11 is a hydrostatic bearing, and the inner surface 13 of the cylindrical portion 12 is the bearing portion 11. The bearing portion 11 of the hydrostatic bearing forms a predetermined bearing gap S by the high-pressure bearing fluid a supplied between the inner surface 13 and the rotating shaft 1, and supports the rotating shaft 1 by the bearing fluid a. The inner surface 13 and the outer surface 14 of the cylindrical portion 12 have a predetermined radial dimension H therebetween.

The cylindrical portion 12 is provided with a planar slit 15 penetrating in the axial direction between the inner surface 13 and the outer surface 14. The planar slit 15 is formed to extend radially from an open end of the outer surface 14 of the cylindrical portion 12, and extends between the outer surface 14 and the inner surface 13 in an arc shape to a predetermined position in the circumferential direction. The planar slit 15 is formed with a predetermined width G (the width of the planar slit 15 is referred to as the radial direction of the cylindrical portion 12), and the predetermined width G may be a minute width of, for example, about 0.1mm to 0.5 mm. The planar slit 15 can be formed by wire electric discharge machining.

The planar slits 15 are formed in a plurality at predetermined intervals in the circumferential direction of the cylindrical portion 12. In the present embodiment, four planar slits 15 are formed at equal intervals in the circumferential direction. The number of the planar slits 15 is not limited to the present embodiment.

In the outer surface 14 of the cylindrical portion 12, one of the circumferential directions is an outer diameter, and the other circumferential direction is a concave portion 16 smaller than the outer diameter, at the open end of the planar slit 15. The outer surface 14 of the cylindrical portion 12 is provided with an outer surface space 17 in which an outer peripheral portion is cut out to a predetermined depth. The outer surface space 17 is provided from the portion of the concave portion 16 to a position separated from the open end of the planar slit 15 by a predetermined distance. The outer surface space 17 is provided in the outer peripheral portion in the radial direction of the portion of the planar slit 15. Thus, the cylindrical portion 12 is fixed to the structure portion 2 at a portion having an outer dimension in one circumferential direction of the planar slit 15, but is attached to the other portion with a gap from the structure portion 2.

According to the above configuration, the planar slit 15 is a fixed end 15a at the outer surface 14 of the cylindrical portion 12, and a free end 15b at the other end. That is, the portion of the planar slit 15 having the outer dimension of the cylindrical portion 12 at the open end is a fixed end 15a, and the other end of the planar slit 15 is a free end 15b bent within a range of a predetermined width G (minute width). According to this configuration, the cylindrical portion 12 can form an arc-shaped spring to elastically support the rotary shaft 1, and the damping effect can be improved. The planar slit 15 can change the stiffness of the arc-shaped spring by the formation position in the radial direction between the inner surface 13 and the outer surface 14 of the cylindrical portion 12. The material of the cylindrical portion 12 may be a material that can exert a spring effect in the portion of the planar slit 15, and for example, stainless steel or the like may be used.

The cylindrical portion 12 is provided with damping fluid supply holes 18 that communicate with the plurality of planar slits 15 from the outer surface 14. The damping fluid O is supplied from the damping fluid supply hole 18 to the planar slit 15. As the "damping fluid" in the present specification and claims, a viscous fluid (oil or the like) for obtaining a damping action is used. Further, high attenuation can be expected by the attenuation function of the viscous fluid. That is, by supplying the damping fluid O into the planar slit 15 from the damping fluid supply hole 18, the radial vibration transmitted from the rotary shaft 1 to the bearing portion 11 can be highly damped by the damping effect of the damping fluid O in the planar slit 15. The attenuation of the planar slit 15 can be made within a range of a predetermined width G (fine width).

In the present embodiment, seal plates 25 that seal the damping fluid O so as not to leak to the surroundings are provided on both end surfaces in the axial direction of the cylindrical portion 12. The periphery of the sealing plate 25 is sealed by an O-ring 26 as a sealing member provided in an O-ring groove 27 at a portion closer to the inner diameter than the planar slit 15 of the cylindrical portion 12 and at a portion closer to the outer diameter than the outer surface space 17. The sealing of the O-ring 26 appropriately prevents the damping fluid O from mixing into the bearing fluid a.

In the present embodiment, the cylindrical portion 12 is provided with bearing fluid supply holes 19 at portions spaced apart from each other by a predetermined distance, and the bearing fluid supply holes 19 penetrate from the outer surface 14 to the inner surface 13 serving as the bearing portion 11 without passing through the planar slits 15. In the present embodiment, bearing fluid supply holes 19 are provided in the vertical direction and the horizontal direction between the four planar slits 15, and the bearing fluid a is supplied between the rotary shafts 1 from these bearing fluid supply holes 19. The bearing fluid supply holes 19 are provided between the planar slits 15, whereby the bearing fluid supply holes 19 do not interfere with the planar slits 15. In this way, the bearing fluid supply holes 19 and the damping fluid supply holes 18 are arranged offset in the circumferential direction of the cylindrical portion 12. Therefore, the bearing fluid a can be appropriately supplied to the bearing portion 11 from the bearing fluid supply hole 19 provided at a position where the planar slit 15 is not provided. As the bearing fluid, gas or liquid may be used. The bearing portion 11 of the present embodiment is a static pressure gas bearing using gas.

Further, an O-ring 21 for sealing the periphery of the bearing fluid supply hole 19 is provided in the outer surface 14 of the cylindrical portion 12 at the portion of the bearing fluid supply hole 19. The O-ring 21 is provided in an O-ring groove 22 provided in the cylindrical portion 12. The cylindrical portion 12 is attached to the structural portion 2, whereby the bearing fluid supply portion 20 of the structural portion 2 is also sealed.

According to the first damper bearing 10, the bearing fluid supplied from the bearing fluid supply hole 19 to the bearing portion 11 can function as a hydrostatic bearing that supports the rotary shaft 1 in a non-contact state. Further, the vibration transmitted in the radial direction from the bearing portion 11 can be damped by the damping fluid O in the plurality of planar slits 15 extending in the circumferential direction between the outer surface 14 and the inner surface 13 of the cylindrical portion 12. Therefore, according to the first damper bearing 10, the bearing portion 11 of the hydrostatic bearing is provided on the inner surface 13 of the cylindrical portion 12, and the bearing having the damping function by the planar slit 15 can be configured to be compact in size in the radial direction.

(Structure of damping bearing according to second embodiment)

Fig. 3 is a front view showing a second damping bearing 30 according to a second embodiment of the present invention. Fig. 4 is an IV-IV cross-sectional view of the second damping bearing 30 shown in fig. 3. Since the hydrostatic bearing is similar in structure to the first damper bearing 10, the same structure is denoted by a reference numeral "20" and detailed description thereof is omitted.

The second damper bearing 30 according to the second embodiment also includes: a bearing portion 31 for supporting the rotary shaft 1; and a cylindrical portion 32 located on the outer periphery of the bearing portion 31 and attached to the structure portion 2. The bearing portion 31 is also a hydrostatic bearing, and the inner surface 33 of the cylindrical portion 32 is the bearing portion 31. The cylindrical portion 32 is provided with a planar slit 35. The planar slit 35 is formed to extend radially from an open end of the outer surface 34 of the cylindrical portion 32, and extends in an arc shape to a predetermined position in the circumferential direction between the outer surface 34 and the inner surface 33. The planar slit 35 is formed to have a predetermined width G (fine width). The planar slit 35 is the same as the planar slit 15 of the first damper bearing 10, and therefore, detailed description thereof is omitted.

A bearing fluid supply hole 39 is provided in a portion of the cylindrical portion 32 where the planar slits 35 are spaced apart by a predetermined distance, and the bearing fluid supply hole 39 penetrates from the outer surface 34 to the inner surface 33 as the bearing portion 31 without passing through the planar slits 35. In the present embodiment, bearing fluid supply holes 39 are provided in the vertical direction and the horizontal direction between the four planar slits 35, and the bearing fluid a is supplied from these bearing fluid supply holes 39. The bearing fluid supply holes 39 are provided between the planar slits 35, whereby the bearing fluid supply holes 39 do not interfere with the planar slits 35. Therefore, the bearing fluid a can be appropriately supplied to the bearing portion 31 from the bearing fluid supply hole 39 provided at a position where the planar slit 35 is not provided. The bearing portion 31 of the present embodiment is also a static pressure gas bearing using gas as the bearing fluid a.

Further, an O-ring 41 for sealing the periphery of the bearing fluid supply hole 39 is provided in the outer surface 34 of the cylindrical portion 32 at the portion of the bearing fluid supply hole 39. The O-ring 41 is provided in an O-ring groove 42 provided in the cylindrical portion 32. The cylindrical portion 32 is attached to the structural portion 2, whereby the space between the bearing fluid supply portions 40 of the structural portion 2 is also sealed.

The cylindrical portion 32 includes an outer surface space 37 in which the solid damper element 50 is disposed on an outer surface 34 outside the planar slit 15. The outer surface space 37 is formed by cutting a predetermined depth from the outer surface 34 of the cylindrical portion 32. A solid damping element 50 is provided in the outer surface space 37. As the solid damper element 50, a member in which a wire mesh 51 is formed to have a predetermined thickness is used in this example. According to the screen 51, the vibration in the radial direction can be damped by the friction caused by the deformation of the screen 51.

The cylindrical portion 32 is provided with holding members 55 as holding portions for preventing the axial movement of the solid damper element 50 at both ends in the axial direction. The holding member 55 is a disk-shaped member having an inner diameter larger than the position of the planar slit 15 of the cylindrical portion 32 and an outer diameter larger than the outer diameter of the cylindrical portion 32. The holding members 55 are provided at both ends in the axial direction in the cylindrical portion 32 and are connected by bolts 56. The holding member 55 as the holding portion is an example, and may have another configuration. By providing the holding member 55, the solid damper element 50 disposed in the outer surface space 37 can be prevented from moving in the axial direction.

According to the second damper bearing 30, even if vibration generated by the rotary shaft 1 is transmitted to the bearing portion 31, friction due to deformation of the wire mesh 51, which is a solid damper element provided in the outer surface space 37 at the outer surface of the cylindrical portion 32, can be appropriately damped. Therefore, the vibration in the radial direction transmitted from the rotary shaft 1 to the bearing portion 31 can be appropriately damped by the second damper bearing 30.

Further, according to the present embodiment, since the damping function of the solid damper element 50 is provided, it is not necessary to supply a damping fluid such as oil into the planar slit 15, and it is possible to provide a structure not using oil. Further, since the solid damper element 50 can be provided over the entire width of the cylindrical portion 32 to improve the damping effect, the radial dimension of the cylindrical portion 32 can be made small, and a bearing suitable for a small-sized rotary machine not using oil can be configured.

(other examples of solid damping elements)

Fig. 5 is a partial view showing a different example of the solid damping element 50 shown in fig. 3. Fig. 6 is a top view of solid damping element 50 shown in fig. 5. Fig. 7 is a partial view showing another different example of the solid damping element 50 shown in fig. 3. As the solid damper element 50, in addition to the above-described screen 51, a slit-equipped thin plate 52, spherical particles 54 made of resin, and the like can be used.

The example shown in fig. 5 and 6 is an example in which the solid damper element 50 is a thin plate 52 with slits that is accommodated in the outer surface space 37. As shown in fig. 6, the slit-provided sheet 52 has a width W smaller than the axial dimension of the cylindrical portion 32 and a length L in the circumferential direction that can fit into the outer surface space 37. The slit-equipped thin plate 52 is formed of a thin plate having a thickness of about 0.1mm to 0.3mm, for example. The slit-equipped sheet 52 is provided with slits 53 at predetermined intervals in the longitudinal direction. The slit 53 is formed smaller than the width dimension W. The slit sheet 52 can be bent at the slit 53.

As shown in fig. 5, according to the slit-provided thin plate 52, the radial vibration transmitted to the cylindrical portion 32 can be damped by the partial bending deformation of the slit 53. Therefore, when the solid damper element is the slit thin plate 52, the radial vibration transmitted from the inner surface to the outer surface of the cylindrical portion 32 can be damped by the slit thin plate 52.

The example shown in fig. 7 is an example where the solid damping element 50 is a spherical particle 54 that fills the outer surface space 37. The spherical particles 54 can be formed by collecting small spheres made of resin, metal, ceramic, or the like. The spherical particles 54 can be prevented from moving in the axial direction by the holding member 55 in a state of being filled in the outer surface space 37.

According to the spherical particles 54, the radial vibration transmitted to the cylindrical portion 32 can be damped by friction caused by the movement of the spherical particles 54 in the outer surface space 3. Therefore, when the solid damper element 50 is the spherical particles 54, the radial vibration transmitted from the inner surface 33 to the outer surface 34 of the cylindrical portion 32 can be damped by the spherical particles 54.

(Structure of damping bearing according to third embodiment)

Fig. 8 is a front view showing a third damping bearing 80 according to a third embodiment of the present invention. Since the second damper bearing 30 is different only in the structure of the portion of the planar slit 35 and the other structures are the same, the same reference numerals are assigned to the same structures and the description thereof will be omitted.

The third damper bearing 80 according to the third embodiment is formed such that the predetermined width G of the planar slit 85 is large. The planar slit 85 of the third damper bearing 80 can have a predetermined width G of, for example, about 1mm to 3 mm. The wire mesh 51 as the solid damper element 50 is inserted into the planar slit 85. The solid damper element 50 fitted into the planar slit 85 may be a slit-equipped thin plate 52. Since the other structures are the same as those of the second damping bearing 30, the description thereof is omitted.

According to the third damper bearing 80, even when vibration generated in the rotary shaft 1 is transmitted to the bearing portion 31, vibration is damped by the wire net 51 as a solid damper member incorporated in the planar slit 85 having the predetermined width G. Further, the friction due to the deformation of the wire mesh 51 as the solid damper element provided in the outer surface space 37 on the outer surface of the cylindrical portion 32 can also be damped. Therefore, the third damper bearing 80 can appropriately damp the radial vibration transmitted from the rotary shaft 1 to the bearing portion 31.

In addition, since the solid damper element 50 of the present embodiment has a damping function, it is not necessary to supply a damping fluid such as oil into the planar slit 85, and it is not necessary to use oil. Therefore, a bearing suitable for a small rotary machine using no oil can be constructed.

(other modification examples)

The second damper bearing 30 is an example of the bearing portion 31 provided as a hydrostatic bearing on the inner surface 33 of the cylindrical portion 32, but the damper 60 can be configured by a structure in which the inner surface 33 does not have a hydrostatic bearing. The same reference numerals are given to the same structure as the second damping bearing 30, and the description thereof will be omitted. The cylindrical portion 62 has the same structure as the cylindrical portion 32 of the second damping bearing 30 described above, but does not have the bearing fluid supply hole 39. According to the damper 60, the rolling bearing 70 can be provided on the inner surface 63 of the cylindrical portion 62.

Fig. 9 is a front view showing an example of providing a rolling bearing 70 in the damper 60 of the present invention. In this example, the outer ring 71 of the rolling bearing 70 is attached to the inner surface 63 of the cylindrical portion 62 of the damper 60 with a predetermined tolerance. The inner ring 72 of the rolling bearing 70 is attached to the rotary shaft 1 with a predetermined tolerance. This example is an example in which the fourth damper bearing 90 having a damper function is formed by attaching the rolling bearing 70 to the damper 60.

According to the fourth damper bearing 90, even in the structure including the rolling bearing 70 in which the radial vibration is hardly damped, the vibration transmitted in the radial direction can be properly damped in the entire axial direction by the solid damper element 50.

In the above embodiment, the example in which four planar slits 15 are provided at equal intervals has been described, but the number of planar slits 15 is not limited. Two planar slits 15 may be provided so as to face each other, or three, five or more planar slits 15 may be provided at equal intervals. The number of the planar slits 15 is not limited to the above embodiment.

The above embodiments are merely examples, and various modifications can be made within a range not impairing the spirit of the present invention, and the present invention is not limited to the above embodiments.

(conclusion)

As described above, according to the first damper bearing 10 and the second damper bearing 30, the bearing portions 11 and 31, which are hydrostatic bearings, can be provided, and the structure having the vibration damping function in the entire axial direction of the tubular portions 12 and 32 can be formed to have a small dimension in the radial direction. Therefore, the small-sized rotary machine can be provided with the damper bearing. Further, according to the damper bearings 10 and 30, in a small-sized high-speed rotating machine (for example, a high-speed small-sized rotating machine such as a centrifugal compressor or a hydrogen expansion turbine) in which the rotating shaft 1 is supported by a hydrostatic bearing, vibration from the rotating shaft 1 can be attenuated to improve performance.

Further, according to the damper 60, the solid damper element 50 provided in the entire axial direction of the cylindrical portion 62 can provide a large damping effect, and the damper can be formed to have a small dimension in the radial direction. Therefore, the bearing can be used as a bearing for a small-sized rotary machine. In particular, a damping bearing advantageous for a small rotary machine using no oil can be constituted. The damper 60 can be used for a rotary machine (for example, a small gas turbine, an aircraft engine, a turbo refrigerator, or the like) supported by the rolling bearing 70, is compact and lightweight, and can stably exhibit a vibration damping effect.

Description of the symbols:

1 rotating shaft

10 first damping bearing

11 bearing part

12 cylindrical part

13 inner surface

14 outer surface

15 planar slit

15a fixed end

15b free end

17 outer surface space

18 damping fluid supply orifice

19 bearing fluid supply hole

30 second damping bearing

31 bearing part

32 cylindrical part

33 inner surface

34 outer surface of the container

35 planar slit

35a fixed end

35b free end

37 outer surface space

39 bearing fluid supply hole

50 solid damping element

51 mesh

52 thin plate with slits

54 spherical particle

55 holding member (holding part)

60 damping

62 cylindrical part

63 inner surface

70 rolling bearing

80 third damping bearing

90 fourth damping bearing

A bearing fluid

Fluid for O damping

G specified width

Dimension in radial direction of H

S bearing clearance.