Bearing device

Abstract

This bearing device (1) is provided with: an outer ring (2) having a pair of outer ring raceways (2b) on an inner peripheral surface (2a); an inner ring (4) having a pair of inner ring raceways (4b) on an outer peripheral surface (4a); a plurality of balls (6) arranged in two rows between the pair of outer ring raceways (2b) and the pair of inner ring raceways (4b); and a cylindrical porous member (8) which is disposed between the rows of the plurality of balls (6) arranged in the two rows and which can be impregnated with lubricating oil. The porous member (8) has a C-shaped radial cross section by having a notch (32) cut out of a part in the circumferential direction.

Description

Bearing device

[0001] The present invention relates to a bearing device.

[0002] A spindle unit of a spinning machine may have a pair of upper and lower rolling bearings for supporting the spindle rotatably relative to a support shaft (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2002-220752

[0004] A pair of rolling bearings supporting a spindle may be integrally configured. FIG. 5 is a cross-sectional view showing an example of a bearing device in which a pair of rolling bearings are integrally configured. In FIG. 5, the bearing device 100 includes an outer ring 102, an inner ring 104, a plurality of balls 106, and a porous member 108. The plurality of balls 106 are arranged in two rows between the outer ring 102 and the inner ring 104. The porous member 108 is cylindrical. The porous member 108 is disposed between the rows of the plurality of balls 106. The porous member 108 is made of a porous material that can be impregnated with lubricating oil. In other words, the porous member 108 is capable of retaining the lubricating oil by being impregnated with the lubricating oil. The lubricating oil retained in the porous member 108 gradually seeps out and is supplied to the contact areas between the inner and outer rings 102 and 104 and the plurality of balls 106. This allows lubrication of the contact areas between the inner and outer rings 102, 104 and the plurality of balls 106 for a long period of time without external oil supply.

[0005] The cylindrical porous member 108 is attached to the outer peripheral surface of the inner ring or the inner peripheral surface of the outer ring before the balls 106 are arranged. This positions the porous member 108 between the rows of balls 106. Urethane sponge, for example, can be considered as a material for the porous member. Urethane sponge can be easily elastically deformed. Therefore, a porous member made of urethane sponge can easily elastically deform to match the shape of the inner and outer rings, and can be easily attached to the inner and outer rings. However, urethane sponge has the problem of significant deterioration over time due to hydrolysis and other factors. In response to this, it is considered to use PVA (polyvinyl alcohol) sponge or polyethylene sponge, which change less over time than urethane sponge, as the material for the porous member 108.

[0006] However, PVA sponge and polyethylene sponge have higher rigidity than urethane sponge and are difficult to elastically deform depending on the shape and dimensions of the inner and outer rings, which can make attachment to the inner and outer rings difficult. Thus, porous member 108 has had the problem that it can be difficult to attach to the inner and outer rings depending on its material.

[0007] Therefore, an object of the present disclosure is to provide a technique that can facilitate the attachment of porous members to inner and outer rings.

[0008] The bearing device of this embodiment comprises an outer ring having a pair of outer ring raceways on its inner peripheral surface, an inner ring having a pair of inner ring raceways on its outer peripheral surface, a plurality of balls arranged in two rows between the pair of outer ring raceways and the pair of inner ring raceways, and a cylindrical porous member that can be impregnated with lubricating oil and is arranged between the two rows of the plurality of balls, and the porous member has a cutout portion with a portion of its circumference cut out, giving it a C-shaped radial cross section.

[0009] According to the present disclosure, it is possible to easily attach the porous members to the inner and outer rings.

[0010] Fig. 1 is a cross-sectional view of a bearing device according to an embodiment. Fig. 2 is an enlarged cross-sectional view of a main portion of the bearing device in Fig. 1. Fig. 3 is a cross-sectional view taken along the line II-II in Fig. 1. Fig. 4 is a view showing the inner and outer rings with a portion of the outer peripheral surface of the inner ring brought close to the inner peripheral surface of the outer ring, providing a gap between the inner and outer rings for incorporating balls. Fig. 5 is a cross-sectional view showing an example of a bearing device in which a pair of rolling bearings are integrally configured.

[0011] First, the contents of the embodiments will be listed and explained. [Outline of the Embodiments] (1) A bearing device according to the embodiment includes an outer ring having a pair of outer ring raceways on its inner peripheral surface, an inner ring having a pair of inner ring raceways on its outer peripheral surface, a plurality of balls arranged in two rows between the pair of outer ring raceways and the pair of inner ring raceways, and a cylindrical porous member that is arranged between the two rows of balls and can be impregnated with lubricating oil, and the porous member has a cutout portion that is partially cut out in the circumferential direction, thereby giving it a C-shaped radial cross section.

[0012] According to the above configuration, the porous member has a C-shaped radial cross section, which makes it easy to deform the porous member so as to expand or contract its diameter. This makes it easy to elastically deform the porous member in accordance with the shapes and dimensions of the inner and outer rings, facilitating attachment of the porous member to the inner and outer rings.

[0013] (2) In the above-described bearing device, the inner ring may be provided between the pair of outer ring raceways and have an oil feed hole communicating with the inner and outer peripheral surfaces of the outer ring, and the circumferential position of the cutout portion may be different from the circumferential position of the oil feed hole. If lubricating oil is supplied when the circumferential position of the cutout portion and the circumferential position of the oil feed hole are aligned, the lubricating oil may flow along the cutout portion and leak out without being retained by the porous member. By making the circumferential position of the cutout portion and the circumferential position of the oil feed hole different from each other, the lubricating oil can be reliably brought into contact with and retained by the porous member, and leakage of the lubricating oil from between the inner and outer rings can be suppressed.

[0014] (3) In the above-described bearing device, the inner circumferential surface preferably has an inner circumferential surface portion against which the outer circumferential surface of the porous member abuts and a first annular groove recessed radially outward relative to the inner circumferential surface portion, and the oil feed hole opens into the first annular groove. In this case, the lubricating oil supplied through the oil feed hole can be temporarily stored in the first annular groove before being retained in the porous member. This prevents the excess lubricating oil from flowing back from the oil feed hole, even if, for example, the lubricating oil is supplied at a rate relatively fast compared to the rate at which the lubricating oil is impregnated into the porous member, resulting in excess lubricating oil not being impregnated into the porous member. By being stored in the first annular groove, the excess lubricating oil is subsequently impregnated into and retained in the porous member.

[0015] (4) In the above-described bearing device, the first annular groove preferably connects to a first axial edge of the inner peripheral surface portion. In this case, if the outer ring is positioned so that the first edge of the inner peripheral surface portion faces upward, the oil feed hole can be positioned upward between the pair of outer ring raceways. Therefore, the lubricating oil fed from the oil feed hole is supplied to a position toward the upper side of the porous member. As a result, the lubricating oil is impregnated into the upper side of the porous member and is retained throughout the entire area of ​​the porous member, from the upper side to the lower side.

[0016] (5) In the above-described bearing device, the inner circumferential surface may further include an annular wall portion that connects to a second edge of the inner circumferential surface portion located axially opposite the first edge and that protrudes radially inward from the inner circumferential surface portion, and a second annular groove that is provided between the inner circumferential surface portion and the annular wall portion and that is recessed radially outward from the inner circumferential surface portion. In this case, when the inner and outer rings are arranged so that the first edge of the inner circumferential surface portion faces upward, the lower end face of the porous member abuts against the annular wall portion, preventing the porous member from falling downward. Furthermore, the second annular groove can collect lubricating oil that flows downward through the porous member, preventing excessive lubricating oil from being supplied to the lower outer ring raceway and inner ring raceway.

[0017] (6) Furthermore, the second annular groove functions as a recess between the annular wall portion and the inner circumferential surface portion. This makes it easy to form the annular wall portion with a wall surface parallel to the radial direction. By forming the annular wall portion with a wall surface parallel to the radial direction, it is possible to more effectively prevent the porous member from falling downward.

[0018] (7) Furthermore, in the above-described bearing device, it is preferable that the inner circumferential surface has an inner circumferential surface portion against which the outer circumferential surface of the porous member abuts, an annular wall portion that is connected to an edge on one axial side of the inner circumferential surface portion and rises radially inward from the inner circumferential surface portion, and an annular groove that is provided between the inner circumferential surface portion and the annular wall portion and is recessed radially outward from the inner circumferential surface portion.

[0019] (8) Furthermore, in the above-described bearing device, when the outer peripheral surface has an annular recess disposed between the pair of inner ring raceways and recessed radially inward, the annular recess may be disposed over an axial range including the entire axial length of the porous member. In this case, by disposing the inner ring on the inner peripheral side of the outer ring and bringing a portion of the outer peripheral surface of the inner ring close to the inner peripheral surface of the outer ring, when attempting to provide a gap for installing balls between the inner and outer rings, the porous member can escape into the annular recess, allowing a portion of the outer peripheral surface of the inner ring to be sufficiently close to the inner peripheral surface of the outer ring. As a result, the porous member can be prevented from interfering with the provision of a gap for installing balls.

[0020] [Details of the embodiment] Preferred embodiments will now be described with reference to the drawings. Fig. 1 is a cross-sectional view of a bearing device according to an embodiment. The bearing device 1 of this embodiment is used, for example, in a spindle unit of a spinning machine. The bearing device 1 supports the spindle of the spindle unit so that it can rotate freely relative to a support shaft. The bearing device 1 includes an outer ring 2, an inner ring 4, a plurality of balls 6, and a porous member 8. Fig. 1 shows a cross section including a center line C of the bearing device 1. The bearing device 1 is positioned so that the center line C is parallel to the vertical direction of Fig. 1.

[0021] In the present disclosure, the direction parallel to the center line C passing through the axial centers of the inner ring 4 and the outer ring 2 is defined as the axial direction, the direction perpendicular to the center line C is defined as the radial direction, and the direction along a circle centered on the center line C is defined as the circumferential direction. Additionally, the upward direction in the axial direction is defined as the first axial direction, and the downward direction is defined as the second axial direction.

[0022] The outer ring 2 is an annular member formed using bearing steel, mechanical structural steel, or the like. The outer ring 2 has a pair of outer ring raceways 2b on its inner peripheral surface 2a. The outer ring 2 is fixed integrally to the housing. The inner ring 4, like the outer ring 2, is an annular member formed using bearing steel, mechanical structural steel, or the like. The inner ring 4 has a pair of inner ring raceways 4b on its outer peripheral surface 4a. The inner ring 4 is fixed to a support shaft. The upper opening between the outer ring 2 and the inner ring 4 is sealed by an annular upper seal member 10. Furthermore, the lower opening between the outer ring 2 and the inner ring 4 is sealed by an annular lower seal member 12.

[0023] The plurality of balls 6 are members formed using bearing steel or the like. The plurality of balls 6 are interposed between a pair of outer ring raceways 2b and a pair of inner ring raceways 4b. Therefore, the plurality of balls 6 are arranged in two rows between the pair of outer ring raceways 2b and the pair of inner ring raceways 4b. The bearing device 1 also has a pair of cages 7. The pair of cages 7 hold the balls 6 in each of the two rows so that they are equally spaced circumferentially. The plurality of balls 6 are interposed between the outer ring raceway 2b and the inner ring raceway 4b so as to be able to roll freely. This allows the outer ring 2 and the inner ring 4 to rotate relative to each other.

[0024] The porous member 8 is a cylindrical member. The porous member 8 is disposed between two rows of balls 6. The porous member 8 is formed from a porous material that can be impregnated with lubricating oil for lubricating the bearing device 1. Examples of porous materials include PVA sponge and polyethylene sponge. In addition to being able to be impregnated with lubricating oil, PVA sponge and polyethylene sponge deteriorate less over time than urethane sponge, allowing for long-term use.

[0025] The outer peripheral surface 8a of the porous member 8 abuts against the inner peripheral surface 2a of the outer ring 2. The inner peripheral surface 2a of the outer ring 2 has a first inner peripheral surface portion 16, a second inner peripheral surface portion 18, a third inner peripheral surface portion 20, a first annular groove 22, and a second annular groove 24. The first inner peripheral surface portion 16 is the upper end portion (end portion on the first axial direction) of the inner peripheral surface 2a of the outer ring 2. The first inner peripheral surface portion 16 includes the upper outer ring raceway 2b of the pair of outer ring raceways 2b. The third inner peripheral surface portion 20 is the lower end portion (end portion on the second axial direction) of the inner peripheral surface 2a of the outer ring 2. The third inner peripheral surface portion 20 includes the lower outer ring raceway 2b of the pair of outer ring raceways 2b. The second inner peripheral surface portion 18 is provided between the first inner peripheral surface portion 16 and the third inner peripheral surface portion 20. The outer peripheral surface 8 a of the porous member 8 abuts against the second inner peripheral surface portion 18 .

[0026] The first annular groove 22 is provided between the first inner circumferential surface portion 16 and the second inner circumferential surface portion 18. The first annular groove 22 is provided around the entire circumference of the inner circumferential surface 2a. The first annular groove 22 is recessed radially outward with respect to the first inner circumferential surface portion 16 and the second inner circumferential surface portion 18. The second annular groove 24 is provided between the second inner circumferential surface portion 18 and the third inner circumferential surface portion 20. The second annular groove 24 is provided around the entire circumference of the inner circumferential surface 2a. The second annular groove 24 is recessed radially outward with respect to the second inner circumferential surface portion 18 and the third inner circumferential surface portion 20.

[0027] 2 is an enlarged cross-sectional view of a main portion of the bearing device 1 in FIG. 1. The inner diameter of the second inner peripheral surface portion 18 is larger than the inner diameter of the first inner peripheral surface portion 16 and the inner diameter of the third inner peripheral surface portion 20. Therefore, the second inner peripheral surface portion 18 is recessed radially outward relative to the first inner peripheral surface portion 16 and the third inner peripheral surface portion 20.

[0028] The first annular groove 22 has an upper annular wall 22a, a lower annular wall 22b, and a bottom surface 22c. The upper annular wall 22a is a wall portion that rises radially inward from the upper edge of the bottom surface 22c. The inner peripheral edge of the upper annular wall 22a is connected to the lower edge of the first inner circumferential surface portion 16. The lower annular wall 22b is a wall portion that rises radially inward from the lower edge of the bottom surface 22c. The inner peripheral edge of the lower annular wall 22b is connected to a first edge 18a of the second inner circumferential surface portion 18. The first edge 18a is the edge on the axially upper side (first axial side) of the second inner circumferential surface portion 18.

[0029] The second annular groove 24 has an upper annular wall 24a, a lower annular wall 24b, and a bottom surface 24c. The upper annular wall 24a is a wall portion that rises radially inward from the upper edge of the bottom surface 24c. The inner peripheral edge of the upper annular wall 24a is connected to the second edge 18b of the second inner circumferential surface portion 18. The second edge 18b is the edge on the axially lower side (second axial direction side) of the second inner circumferential surface portion 18. The lower annular wall 24b is a wall portion that rises radially inward from the lower edge of the bottom surface 22c. The inner peripheral edge of the lower annular wall 22b is connected to the upper edge of the third inner circumferential surface portion 20.

[0030] Here, the upper annular wall 22a of the first annular groove 22 is connected to the first inner circumferential surface portion 16. Furthermore, the lower annular wall 24b of the second annular groove 24 is connected to the third inner circumferential surface portion 20. Therefore, the upper annular wall 22a has an annular wall portion 22a1 that protrudes radially inward beyond the second inner circumferential surface portion 18. Furthermore, the lower annular wall 24b has an annular wall portion 24b1 that protrudes radially inward beyond the second inner circumferential surface portion 18.

[0031] An upper end face 8b (on the first axial direction) of the porous member 8 faces the annular wall portion 22a1. A lower end face 8c (on the second axial direction) of the porous member 8 faces the annular wall portion 24b1. That is, the porous member 8 is provided in the axial range between the annular wall portion 22a1 and the annular wall portion 24b1. The end faces 8b and 8c may abut against the annular wall portion 22a1 and the annular wall portion 24b1. The movement of the porous member 8 in the axial direction is restricted by the annular wall portion 22a1 and the annular wall portion 24b1.

[0032] Furthermore, the porous member 8 is disposed so as to block the first annular groove 22 and the second annular groove 24. Therefore, an annular space is provided between the first annular groove 22 and the outer peripheral surface 8 a of the porous member 8. Similarly, an annular space is provided between the second annular groove 24 and the outer peripheral surface 8 a.

[0033] The outer ring 2 has an oil supply hole 28. The oil supply hole 28 communicates between the inner circumferential surface 2a and the outer circumferential surface 2c of the outer ring 2. The oil supply hole 28 opens to the bottom surface 22c of the first annular groove 22. The oil supply hole 28 is a hole for supplying lubricating oil from the outside of the bearing device 1 to the inside of the bearing device 1. The lubricating oil is supplied to the inside of the bearing device 1 through the oil supply hole 28.

[0034] FIG. 3 is a cross-sectional view taken along line II-II in FIG. 1 , showing a cross section (radial cross section) of the bearing device 1 taken along a plane perpendicular to the center line C. As shown in FIG. 3 , the porous member 8 has a main body 30 and a cutout 32. The cutout 32 is provided by cutting out a portion of the porous member 8 in the circumferential direction. This gives the main body 30 a C-shaped radial cross section. The main body 30 has a first end face 30a and a second end face 30b. The first end face 30a is an end face on one side of the main body 30 in the circumferential direction. The second end face 30b is an end face on the opposite side of the first end face 30a in the circumferential direction of the main body 30. The first end face 30a and the second end face 30b face each other at a predetermined distance. The cutout 32 is defined by the first end face 30a and the second end face 30b.

[0035] 3, the circumferential positions of the cutout portions 32 and the circumferential positions of the oil supply holes 28 are different from each other. More specifically, the cutout portions 32 and the oil supply holes 28 are disposed on opposite sides of the center line C.

[0036] If lubricating oil were supplied when the circumferential positions of the cutouts 32 and the oil feed holes 28 were aligned, the lubricating oil would flow along the cutouts 32 and risk leaking out without being retained by the porous member 8. In this regard, in the present embodiment, the circumferential positions of the cutouts 32 and the oil feed holes 28 are different from each other, so the lubricating oil can be reliably brought into contact with and retained in the porous member 8, and leakage of the lubricating oil from between the inner and outer rings can be suppressed.

[0037] Because the porous member 8 has the cutout portion 32, it can be elastically deformed so that the outer diameter of the porous member 8 decreases. The porous member 8 is attached to the outer ring 2 in a state in which it is elastically deformed so that its outer diameter decreases. Therefore, the diameter of the outer peripheral surface 8a of the porous member 8 in a free state is larger than the inner diameter of the second inner peripheral surface portion 18 of the outer ring 2.

[0038] In the present embodiment, the porous member 8 has a C-shaped radial cross section, which makes it easy to deform the porous member 8 so as to expand or contract the diameter. This makes it easy to elastically deform the porous member 8 in accordance with the shapes and dimensions of the inner and outer rings 2, 4, and makes it easy to attach the porous member 8 to the inner and outer rings 2, 4.

[0039] That is, even if a relatively rigid material such as PVA sponge or polyethylene sponge is used as the material for the porous member 8, the cutouts 32 make it easy to elastically deform the porous member 8 so that the outer diameter thereof decreases. Thus, even when a porous member 8 whose outer diameter is larger than the inner diameter of the inner circumferential surface 2 a of the outer ring 2 is attached to the inner circumferential surface 2 a of the outer ring 2, such attachment is easy.

[0040] Furthermore, in this embodiment, since the oil feed hole 28 opens into the first annular groove 22, the lubricating oil supplied from the oil feed hole 28 can be temporarily stored in the first annular groove 22 before being held in the porous member 8. As described above, an annular space is provided between the first annular groove 22 and the outer peripheral surface 8 a of the porous member 8. The lubricating oil is temporarily stored in this annular space. As a result, even if excess lubricating oil is generated that is not impregnated into the porous member 8, for example, because the lubricating oil is supplied at a rate relatively fast compared to the rate at which the lubricating oil is impregnated into the porous member 8, it is possible to prevent this excess lubricating oil from flowing back from the oil feed hole. The excess lubricating oil is stored in the annular space of the first annular groove 22 and is then impregnated into and held in the porous member 8.

[0041] Furthermore, in this embodiment, the inner and outer rings are arranged so that the first edge 18a of the second inner circumferential surface portion 18 faces upward. Therefore, the oil supply hole 28 can be positioned upward between the pair of outer ring raceways 2b. Therefore, the lubricating oil supplied from the oil supply hole 28 is supplied to a position toward the upper side of the porous member 8. As a result, the lubricating oil is impregnated from the upper side of the porous member 8 and is held throughout the entire area of ​​the porous member 8, from the upper side to the lower side.

[0042] In this embodiment, the lower end face 8c of the porous member 8 abuts against the annular wall portion 24b1 of the lower annular wall 24b, preventing the porous member 8 from falling downward. Furthermore, the lubricating oil that flows downward through the porous member 8 can be collected in the second annular groove 24, preventing more lubricating oil than necessary from being supplied to the lower outer ring raceway 2b and inner ring raceway 4b.

[0043] The second annular groove 24 also functions as a recess between the lower annular wall 24b (annular wall portion 24b1) and the second inner circumferential surface portion 18. This makes it easy to form the lower annular wall 24b with a wall surface parallel to the radial direction. By forming the lower annular wall 24b with a wall surface parallel to the radial direction, it is possible to more effectively prevent the porous member 8 from falling downward.

[0044] As shown in Fig. 2, the outer peripheral surface 4a of the inner ring 4 has a first outer peripheral surface portion 34, a second outer peripheral surface portion 36, and an annular recess 38. The first outer peripheral surface portion 34 is a portion of the outer peripheral surface 4a that faces the first inner peripheral surface portion 16 of the outer ring 2. The first outer peripheral surface portion 34 includes the upper inner ring raceway 4b of the pair of inner ring raceways 4b. The second outer peripheral surface portion 36 is a portion of the outer peripheral surface 4a that faces the third inner peripheral surface portion 20 of the outer ring 2. The second outer peripheral surface portion 36 includes the lower inner ring raceway 4b of the pair of inner ring raceways 4b.

[0045] The annular recess 38 is provided over an axial range including the entire axial area of ​​the porous member 8. By providing this annular recess 38, a portion of the outer peripheral surface 4a of the inner ring 4 can be brought sufficiently close to the inner peripheral surface 2a of the outer ring 2, and the porous member 8 can be prevented from interfering with the formation of a gap between the inner and outer rings 2, 4 for fitting the balls 6 therein.

[0046] Figure 4 shows the inner ring 4 and outer ring 2 with a portion of the outer peripheral surface 4a of the inner ring 4 approaching the inner peripheral surface 2a of the outer ring 2, providing a gap between the inner and outer rings 2, 4 for installing balls 6. In Figure 4, gap S is the gap for installing balls 6 between the inner and outer rings 2, 4. Gap S is provided during assembly of the bearing device 1. Gap S is provided by positioning the inner ring 4 on the inner peripheral side of the outer ring 2 to which the porous member 8 is attached, and then making the inner and outer rings 2, 4 eccentric to each other. Multiple balls 6 are installed between the inner and outer rings 2, 4 sequentially from gap S.

[0047] As shown in Figure 4, when a portion 4a1 of the outer peripheral surface 4a of the inner ring 4 is brought close to the inner peripheral surface 2a of the outer ring 2 to provide the gap S, the gap between the outer peripheral surface 4a and the inner peripheral surface 2a is reduced. At this time, there is a risk that the porous member 8 attached to the outer ring 2 will become pinched between the outer peripheral surface 4a and the inner peripheral surface 2a, interfering with the provision of the gap S. In contrast, in this embodiment, the outer peripheral surface 4a of the inner ring 4 has the annular recess 38 described above, allowing the porous member 8 to escape into the annular recess 38, allowing the portion 4a1 of the outer peripheral surface 4a of the inner ring 4 to be brought sufficiently close to the inner peripheral surface 2a of the outer ring 2. As a result, the porous member 8 is prevented from interfering with the provision of the gap S.

[0048] [Other] The embodiments disclosed herein are illustrative in all respects and are not limiting. For example, while the above embodiment illustrates a bearing device used in a spindle unit of a spinning machine, the present embodiment can be applied to any bearing device that includes an outer ring having a pair of outer ring raceways on its inner circumferential surface, an inner ring having a pair of inner ring raceways on its outer circumferential surface, and a plurality of balls arranged in two rows between the pair of outer ring raceways and the pair of inner ring raceways. Furthermore, while the above embodiment illustrates a case in which there is one oil supply hole 28, multiple oil supply holes 28 may be provided.

[0049] The scope of the present invention is not limited to the above-described embodiments, but includes all modifications within the scope of equivalents to the configurations described in the claims.

[0050] DESCRIPTION OF SYMBOLS 1: Bearing device 2: Outer ring 2a: Inner peripheral surface 2b: Outer ring raceway 2c: Outer peripheral surface 4: Inner ring 4a: Outer peripheral surface 4b: Inner ring raceway 6: Ball 8: Porous member 8a: Outer peripheral surface 8b: End face 8c: End face 18: Second inner peripheral surface portion (inner peripheral surface portion) 18a: First end edge 18b: Second end edge 22: First annular groove 22a1: Annular wall portion 24: Second annular groove 24b1: Annular wall portion 28: Oil supply hole 30a: First end face 30b: Second end face 32: Notch portion 38: Annular recess

Claims

1. an outer ring having a pair of outer ring raceways on its inner circumferential surface; an inner ring having a pair of inner ring raceways on an outer peripheral surface; a plurality of balls arranged in two rows between the pair of outer ring raceways and the pair of inner ring raceways; a cylindrical porous member that is arranged between the two rows of balls and that can be impregnated with lubricating oil; The porous member has a cutout portion formed by cutting out a part of the circumferential direction, and thus has a C-shaped cross section in the radial direction. Bearing device.

2. the outer ring is provided between the pair of outer ring raceways and has an oil supply hole communicating an inner circumferential surface and an outer circumferential surface of the outer ring, The circumferential position of the cutout portion and the circumferential position of the oil supply hole are different from each other. The bearing device according to claim 1 .

3. The inner circumferential surface is an inner peripheral surface portion with which the outer peripheral surface of the porous member abuts; a first annular groove recessed radially outward relative to the inner circumferential surface portion, The oil supply hole opens into the first annular groove. The bearing device according to claim 2 .

4. The first annular groove is connected to a first axial edge of the inner circumferential surface portion. The bearing device according to claim 3 .

5. The inner circumferential surface is an annular wall portion connected to a second edge of the inner circumferential surface portion located axially opposite to the first edge and protruding radially inward beyond the inner circumferential surface portion; a second annular groove provided between the inner circumferential surface portion and the annular wall portion and recessed radially outward relative to the inner circumferential surface portion. The bearing device according to claim 3 or 4.

6. The annular wall portion has wall surfaces parallel to the radial direction. The bearing device according to claim 5 .

7. The inner circumferential surface is an inner peripheral surface portion with which the outer peripheral surface of the porous member abuts; an annular wall portion connected to an edge on one axial side of the inner circumferential surface portion and rising radially inward from the inner circumferential surface portion; an annular groove provided between the inner circumferential surface portion and the annular wall portion and recessed radially outward relative to the inner circumferential surface portion; The bearing device according to claim 1 .

8. the outer peripheral surface has an annular recess provided between the pair of inner ring raceways and recessed radially inward, The annular recess is provided over an axial range including the entire axial area of ​​the porous member. The bearing device according to any one of claims 1 to 4.