Rolling bearings, rotating machinery, and methods for manufacturing rolling bearings

Abstract

To provide a rolling bearing which can secure durability and achieve reduction of rotational resistance.SOLUTION: A rolling bearing 1 includes an inner ring 10 and an outer ring 20 arranged coaxially with each other, rolling elements 30 disposed between the inner ring 10 and the outer ring 20, a seal member 50 which is attached to the outer ring 20 and covers an area between the inner ring 10 and the outer ring 20 from an axial outer side, and a grease 60 disposed between the rolling elements 30 and the seal member 50. The outer ring 20 has an inner peripheral surface 22b facing the inner ring 10. The inner peripheral surface 22b is provided with: an outer ring raceway surface 23 which supports the rolling elements 30 in a rollable manner; and a recessed part 24 which is provided in a portion extending from an axial end edge of the outer ring raceway surface 23 in an axial direction and recessed in a radial direction. The grease 60 contacts with the recessed part 24.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a rolling bearing, a rotating device, and a method for manufacturing a rolling bearing.

Background Art

[0002] Conventionally, there is a rolling bearing that holds grease between a pair of raceways (inner ring and outer ring). In this type of rolling bearing, the resistance of the grease may be a factor that increases the rotational resistance. By the way, in a rolling bearing, reduction of rotational resistance is desired for the purpose of power saving of the mounted rotating device. Particularly in a small-sized rolling bearing used in various motors such as a fan motor, there is a strong demand for reduction of rotational resistance.

[0003] In order to reduce the rotational resistance of a rolling bearing, it is effective to reduce the amount of grease that contacts both of the members that rotate relative to each other. Therefore, grease is applied to the axial end portion of the fixed ring (in many cases, the outer ring) of the rolling bearing and the seal member disposed on the end portion side, and reduction of the amount of grease that contacts the rolling elements (balls) and the cage that holds the rolling elements is attempted (for example, see Patent Document 1). In the rolling bearing described in Patent Document 1, the grease is adhered to the inner peripheral surface avoiding the raceway surface that contacts the rolling elements of the outer ring, and is enclosed in an annular shape biased to the inner peripheral surface side of the outer ring so as not to contact the outer peripheral surface of the inner ring.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, reducing the amount of grease to lower rotational resistance can lead to a decrease in the lifespan of the rolling bearing due to grease depletion. Therefore, conventional rolling bearings face the challenge of achieving both durability and reduced rotational resistance.

[0006] Therefore, the present invention provides a rolling bearing, a rotating device, and a method for manufacturing a rolling bearing that can achieve both durability and reduced rotational resistance. [Means for solving the problem]

[0007] A rolling bearing according to a first aspect of the present invention comprises an inner ring and an outer ring arranged coaxially with respect to each other, rolling elements disposed between the inner ring and the outer ring, a sealing member mounted on the inner ring or the outer ring and covering the space between the inner ring and the outer ring from the outside in the axial direction, and grease disposed between the rolling elements and the sealing member, wherein one of the inner ring and the outer ring has a circumferential surface facing the other raceway, and the circumferential surface has a raceway surface that supports the rolling elements so as to be able to roll, and a recess that is provided at a location extending in the axial direction from the axial edge of the raceway surface and is recessed in the radial direction, and the grease is in contact with the recess.

[0008] According to the first embodiment, the axial displacement of the grease can be restricted by the recess. This prevents the grease from displacing and coming into contact with the rolling elements or other components in an amount greater than desired. Therefore, the rotational resistance of the rolling bearing can be reduced. Furthermore, since the grease can be placed inside the recess, the total amount of grease can be increased compared to a configuration without a recess. As a result, a rolling bearing that achieves both durability and reduced rotational resistance can be provided.

[0009] A rolling bearing according to a second aspect of the present invention is a rolling bearing according to the first aspect described above, wherein the grease may be in contact with a portion of the recess that is inclined outward in the axial direction with respect to the radial direction.

[0010] According to the second embodiment, the portion of the recess that is inclined outward in the axial direction with respect to the radial direction restricts the displacement of the grease inward in the axial direction from the initial state. As a result, the grease is less likely to displace inward in the axial direction from its initial position during repeated use of the rolling bearing, allowing for an increase in the amount of grease to be sealed inside, and thus the above effects can be obtained more reliably. In addition, the shape and position of the grease are less likely to change due to vibrations during transportation or long-term storage (especially storage in high-temperature environments). Therefore, it is possible to provide a rolling bearing in which fluctuations in rotational resistance from the initial stage of manufacturing are suppressed.

[0011] A rolling bearing according to a third aspect of the present invention is a rolling bearing according to the first or second aspect described above, wherein the recess may have a portion that is inclined inward in the axial direction with respect to the radial direction.

[0012] According to the third embodiment, the portion of the recess that is inclined inward in the axial direction with respect to the radial direction restricts the displacement of the grease outward in the axial direction. This prevents the grease or its base oil from flowing out to the seal member side and leaking out through the gap between the seal member and one of the raceway rings.

[0013] A rolling bearing according to a fourth aspect of the present invention is a rolling bearing according to any of the first to third aspects described above, wherein the grease may be in contact with the sealing member.

[0014] According to the fourth embodiment, when a sealing member is installed with grease applied to one of the raceways, even if the grease in contact with the sealing member is pushed inward in the axial direction by the sealing member, the inward displacement of the grease in the axial direction is restricted by the recess, thereby preventing the grease from contacting the rolling elements or other components in an amount greater than desired. Therefore, the rotational resistance of the rolling bearing can be reduced. In particular, when the grease is in contact with a portion of the recess that is inclined outward in the axial direction relative to the radial direction, the grease is supported not only by the recess but also by the sealing member. Therefore, the shape and position of the grease are less likely to change due to vibrations during transportation or long-term storage (especially storage in high-temperature environments). Consequently, it is possible to provide a rolling bearing in which fluctuations in rotational resistance from the initial stages of manufacturing are suppressed.

[0015] A fifth aspect of the present invention is a rolling bearing according to any of the first to fourth aspects described above, wherein the recess may be provided at an axial distance from the raceway surface.

[0016] According to the fifth aspect, it is possible to suppress contact between the grease in the recess and the rolling elements rolling on the raceway surface. This makes it possible to suppress an increase in the rotational resistance of the rolling bearing.

[0017] A rolling bearing according to a sixth aspect of the present invention is a rolling bearing according to any of the first to fifth aspects described above, wherein one raceway has a projection that protrudes toward the other raceway and has a circumferential surface formed thereon, the projection has an end face that faces outward in the axial direction and connects to the circumferential surface at the periphery on the other raceway side, and the recess may be provided at an axial distance from the end face.

[0018] According to the sixth embodiment, it is possible to prevent the grease or its base oil from flowing out of the recess toward the end face and leaking out through the gap between the end face and the sealing member.

[0019] A rolling bearing according to a seventh aspect of the present invention is a rolling bearing according to any of the first to sixth aspects described above, wherein the recess may extend continuously over the entire circumferential direction.

[0020] According to the seventh aspect, the grease arranged along the circumferential direction can be made difficult to be displaced axially by the recess over its entire length. Therefore, the rotational resistance of the rolling bearing can be reduced. Further, as compared with the configuration in which the recesses are formed discontinuously in the circumferential direction, the amount of grease arranged inside the recesses can be increased.

[0021] The rolling bearing according to the eighth aspect of the present invention is the rolling bearing according to any one of the first to seventh aspects, wherein the grease may be in contact with a ridge portion formed at an edge on the raceway surface side of the recess.

[0022] According to the eighth aspect, since it is not necessary for the base oil that has oozed out from the grease to climb over the ridge portion in the process of reaching the raceway surface, it is possible to suppress the shortage of the supply of the base oil of the grease to the rolling elements.

[0023] The rolling bearing according to the ninth aspect of the present invention is the rolling bearing according to any one of the first to eighth aspects, wherein one of the raceway rings has a protruding portion that protrudes toward the other raceway ring side and on which the circumferential surface is formed, the protruding portion has an end surface that faces the outside in the axial direction and is connected to the circumferential surface at the peripheral edge on the other raceway ring side, the circumferential surface has a connecting surface formed between the recess and the end surface, and the connecting surface may be separated from the other raceway ring farther than the axial edge of the raceway surface in the radial direction.

[0024] According to the ninth aspect, in order to discharge the grease from the nozzle and apply it to a predetermined location, when inserting the tip of the nozzle from the outside of the rolling bearing to the inside of the outer ring and the inner ring, it is possible to make it difficult for the nozzle to contact the connecting surface. For this reason, when applying the grease, it becomes easier to bring the nozzle closer to the recess, so that the productivity of a small-diameter rolling bearing can be improved. Further, since it becomes easier to bring the nozzle closer to the recess, the grease can be applied accurately, and it is possible to suppress the grease from contacting the rolling elements or the like in an amount exceeding the desired amount. Therefore, the rotational resistance of the rolling bearing can be reduced.

[0025] The rolling bearing according to the tenth aspect of the present invention is the rolling bearing according to any one of the first to ninth aspects, wherein the circumferential surface may have an inclined portion that inclines in the radial direction and the axial direction from an edge on the raceway surface side of the concave portion and extends toward the raceway surface side.

[0026] According to the tenth aspect, even if the end portion on the raceway surface side of the concave portion extends along the radial direction, since the circumferential surface gradually inclines from the concave portion toward the raceway surface, it is possible to promote the flow of the base oil that has leaked from the grease along the inclined portion from the concave portion toward the raceway surface. Therefore, even if the grease is not disposed close to the raceway surface, it is possible to suppress a shortage in the supply of the base oil of the grease to the rolling elements.

[0027] The rolling bearing according to the eleventh aspect of the present invention is the rolling bearing according to the tenth aspect, wherein the grease may be disposed so as not to protrude toward the inclined portion in the radial direction from the inside of the concave portion.

[0028] According to the eleventh aspect, it is possible to suppress the grease from contacting the rolling elements. On the other hand, since the amount of grease applied is reduced, it is possible to suitably obtain the effect of suppressing a shortage in the supply of the base oil of the grease to the rolling elements as described above.

[0029] The rolling bearing according to the twelfth aspect of the present invention is the rolling bearing according to any one of the first to eleventh aspects, wherein the seal member has an annular pedestal portion that contacts the one raceway ring from the outside in the axial direction, an extension portion that extends outward in the axial direction from a peripheral edge on the other raceway ring side of the pedestal portion, and a flat portion that extends along the radial direction from an outer edge in the axial direction of the extension portion toward the other raceway ring, the grease has a raceway ring contact portion that contacts the circumferential surface of the one raceway ring, and a seal member contact portion that is outside the raceway ring contact portion in the axial direction and contacts the flat portion on the other raceway ring side, and the area of the seal member contact portion may be larger than the contact area between the grease and the extension portion and the pedestal portion of the seal member.

[0030] According to the twelfth embodiment, when the sealing member is installed after grease has been applied to a predetermined location, there is room for the grease, which has been pushed inward in the axial direction by the flat portion of the sealing member, to spread radially toward the extension portion and the base portion. This prevents the grease from spreading excessively toward one of the raceway rings and the rolling element. Thus, it is easy to prevent the grease from directly contacting the rolling element and one of the raceway rings. Furthermore, since the sealing member has an extension between the flat portion and the base portion, the grease can be positioned further away from the rolling elements compared to a configuration where the flat portion extends radially from the base portion. Therefore, the amount of grease can be increased. As a result, we can provide a rolling bearing that achieves both durability and reduced rotational resistance.

[0031] A rolling bearing according to a thirteenth aspect of the present invention is a rolling bearing according to the twelfth aspect described above, wherein the seal member contact portion may include the radial center position of the grease when viewed from the axial direction.

[0032] According to the 13th embodiment, when the sealing member is installed, the grease is pushed onto the flat surface and spreads radially. As a result, the contact area of ​​the sealing member includes the radial center position of the grease in a plan view, thus suppressing the grease from spreading significantly inward in the axial direction toward the rolling element. Therefore, direct contact between the grease and the rolling element can be easily suppressed.

[0033] In the rolling bearing according to the 14th aspect of the present invention, the grease may not be in contact with the extension portion, as described above in the rolling bearing according to the 12th or 13th aspect.

[0034] According to the 14th embodiment, when the sealing member is installed, a larger amount of space can be provided for the grease, which is pushed axially inward by the flat portion of the sealing member, to spread radially toward the extension portion. Therefore, it is possible to suppress the grease from spreading excessively toward one of the raceway rings and the rolling element. Thus, it is possible to easily suppress the grease from coming into contact with the rolling element, the retainer and one of the raceway rings more than necessary.

[0035] A rolling bearing according to the 15th aspect of the present invention is a rolling bearing according to any of the 12th to 14th aspects described above, wherein the raceway contact portion may be provided at an axial distance from the contact portion between one of the raceway rings and the base portion.

[0036] According to the 15th embodiment, it is possible to avoid the grease coming into contact with the contact area between the raceway ring and the base. This prevents the grease from leaking out to the outside of the sealing member through the contact area between the raceway ring and the base due to capillary action.

[0037] A rolling bearing according to the sixteenth aspect of the present invention is a rolling bearing according to any of the twelveth to fifteenth aspects described above, wherein the grease may not be in contact with the base portion.

[0038] According to the 16th embodiment, it is possible to avoid the grease coming into contact with the contact area between the raceway ring and the base. This prevents the grease from leaking out to the outside of the sealing member through the contact area between the raceway ring and the base due to capillary action.

[0039] A rolling bearing according to the 17th aspect of the present invention is a rolling bearing according to any of the 12th to 16th aspects described above, wherein one raceway has a projection that protrudes toward the other raceway and on which the raceway surface is formed, the projection has an end face that faces outward in the axial direction and connects to the circumferential surface at the periphery on the other raceway side and contacts the base portion, and the base portion may be arranged so as to not protrude toward the other raceway side beyond the end face when viewed from the axial direction.

[0040] According to the 17th embodiment, even if the grease contact portion of the raceway ring expands axially and exceeds the periphery of the end face, it is possible to suppress the grease from adhering to the base portion. Therefore, it is possible to avoid the grease coming into contact with the contact portion between the raceway ring and the base portion. This prevents the grease from leaking out to the outside of the sealing member through the contact portion between the raceway ring and the base portion due to capillary action.

[0041] A rotating device according to the 18th aspect of the present invention comprises a rotatably arranged rotating body, a support that rotatably supports the rotating body, and a rolling bearing interposed between the rotating body and the support, according to any of the first to 17th aspects described above.

[0042] According to the 18th embodiment, since a rolling bearing is provided that achieves both durability and reduced rotational resistance, it is possible to extend the lifespan of the rotating equipment and reduce power consumption of the rotating equipment by reducing the rotational resistance of the rotating body to the support.

[0043] A method for manufacturing a rolling bearing according to a 19th aspect of the present invention comprises an inner ring and an outer ring arranged coaxially with respect to each other, rolling elements disposed between the inner ring and the outer ring, a sealing member mounted on the inner ring or the outer ring and covering the space between the inner ring and the outer ring from the outside in the axial direction, and grease disposed between the rolling elements and the sealing member, wherein one of the inner ring and the outer ring has a circumferential surface facing the other raceway, and the circumferential surface has a raceway surface for supporting the rolling elements so as to be able to roll, and a recess provided at a location extending in the axial direction from the axial edge of the raceway surface and recessed in the radial direction, the method for manufacturing a rolling bearing comprises an application step of applying the grease in contact with the recess.

[0044] According to the 19th embodiment, grease can be applied to one of the raceway rings in such a way that axial displacement is restricted by the recess. This prevents the grease from displacing and coming into contact with the rolling elements or other components in an amount greater than desired. Thus, the rotational resistance of the rolling bearing can be reduced. Furthermore, since the grease can be placed inside the recess, the total amount of grease can be increased compared to when grease is not applied to the recess. As a result, a rolling bearing can be manufactured that achieves both durability and reduced rotational resistance.

[0045] A method for manufacturing a rolling bearing according to a 20th aspect of the present invention is a method for manufacturing a rolling bearing according to the 19th aspect, wherein the seal member has an annular base portion that contacts one of the raceways from the outside in the axial direction, an extension portion that extends outward in the axial direction from the peripheral edge of the base portion on the other raceway side of the inner ring and the outer ring, and a flat portion that extends radially from the outer edge of the extension portion toward the other raceway, and in the coating step, the grease is applied to the one The seal member is applied so as to protrude outward in the axial direction from the contact portion with the raceway ring and toward the other raceway ring, and the seal member is brought close to the one raceway ring from the outside in the axial direction, and the flat portion is brought into contact with the outer edge in the axial direction of the grease, and the seal member is brought close to the one raceway ring after the contact step, and the base portion is brought into contact with the one raceway ring from the outside in the axial direction, and the flat portion is used to push the grease inward in the axial direction.

[0046] According to the 20th embodiment, in the contact process, the flat portion of the sealing member contacts the axially outer edge of the grease. Therefore, in the mounting process, when the flat portion pushes the grease inward in the axial direction, there is room for the grease to spread radially toward the extended portion and base portion of the sealing member. As a result, it is possible to suppress the grease from spreading too much toward the other raceway ring and the rolling element. Thus, it is possible to easily prevent the grease from directly contacting the rolling element and the other raceway ring. Furthermore, since an extension is provided between the flat portion and the base portion, the grease is less likely to be pushed towards the rolling element compared to a configuration where the flat portion extends from the base portion towards the other raceway. Therefore, it becomes possible to place the grease closer to the rolling element in advance, thus increasing the amount of grease used. [Effects of the Invention]

[0047] According to the present invention, it is possible to provide a rolling bearing, a rotating device, and a method for manufacturing a rolling bearing that can achieve both durability and reduced rotational resistance. [Brief explanation of the drawing]

[0048] [Figure 1] This is a plan view of a rolling bearing according to the first embodiment. [Figure 2] This is a longitudinal cross-sectional view along line II-II in Figure 1. [Figure 3] This is a longitudinal cross-sectional view of a rolling bearing illustrating a grease application method according to the first embodiment. [Figure 4] This is a longitudinal cross-sectional view of a rolling bearing illustrating a grease application method according to the first embodiment. [Figure 5] This is a longitudinal cross-sectional view of a rolling bearing according to a first modified example of the first embodiment. [Figure 6] This is a longitudinal cross-sectional view of a rolling bearing according to a second modified example of the first embodiment. [Figure 7] This is a longitudinal cross-sectional view of a rolling bearing according to the second embodiment. [Figure 8] This is a longitudinal cross-sectional view of a rolling bearing according to the third embodiment. [Figure 9] This is a longitudinal cross-sectional view of a rolling bearing according to the fourth embodiment. [Figure 10] This is a longitudinal cross-sectional view of a rolling bearing according to a modified example of the fourth embodiment. [Figure 11] This is a longitudinal cross-sectional view of a rolling bearing according to the fifth embodiment. [Figure 12] This is a longitudinal cross-sectional view of a rolling bearing according to the first modified example of the fifth embodiment. [Figure 13]This is a longitudinal cross-sectional view of a rolling bearing according to a second modified example of the fifth embodiment. [Figure 14] This is a longitudinal cross-sectional view of a rolling bearing according to the sixth embodiment. [Figure 15] This is a longitudinal cross-sectional view of a rolling bearing according to the first modified example of the sixth embodiment. [Figure 16] This is a longitudinal cross-sectional view of a rolling bearing according to a second modified example of the sixth embodiment. [Figure 17] This is a longitudinal cross-sectional view of a rolling bearing according to the seventh embodiment. [Figure 18] This is a longitudinal cross-sectional view of a rolling bearing according to the eighth embodiment. [Figure 19] This is a longitudinal cross-sectional view of a rolling bearing according to the first modified example of the eighth embodiment. [Figure 20] This is a longitudinal cross-sectional view of a rolling bearing according to a second modified example of the eighth embodiment. [Modes for carrying out the invention]

[0049] Embodiments of the present invention will be described below with reference to the drawings. In the following description, components having the same or similar functions will be denoted by the same reference numerals. Duplication of these components may be omitted.

[0050] [First Embodiment] A first embodiment of the present invention will be described with reference to Figures 1 and 2. Figure 1 is a plan view of a rolling bearing according to the first embodiment. Figure 2 is a longitudinal cross-sectional view taken along line II-II in Figure 1. In Figure 2, the rotating equipment 2 on which the rolling bearing 1 is mounted is shown by dashed lines.

[0051] As shown in Figures 1 and 2, the rolling bearing 1 is a radial ball bearing comprising an inner ring 10 and an outer ring 20 which are raceway rings, a plurality of rolling elements 30, a cage 40, and a pair of sealing members 50. The rolling bearing 1 is installed in a rotating device 2 such as a fan motor. The rotating device 2 comprises a shaft 3 (rotating body) formed to be rotatable about a common axis O, and a housing 4 (support) which is fixedly installed and rotatably supports the shaft 3. The rolling bearing 1 is interposed between the shaft 3 and the housing 4.

[0052] The inner ring 10 and the outer ring 20 are arranged coaxially with each other such that their respective central axes coincide with the common axis O. In this embodiment, the direction in which the common axis O extends is called the axial direction, the direction perpendicular to the common axis O and extending radially from the common axis O is called the radial direction, and the direction that circles around the common axis O is called the circumferential direction. Furthermore, one of the directions parallel to the axial direction and pointing in opposite directions is defined as upward, and the other is defined as downward.

[0053] The inner ring 10 is provided as a rotating ring. The inner ring 10 is fitted onto the shaft 3 and fixed to the shaft 3. The outer ring 20 is provided as a stationary ring. The outer ring 20 is fitted into a recess (or through hole) in the housing 4 and fixed to the housing 4. The outer ring 20 surrounds the inner ring 10 from the radial outside, with an annular space between them. Multiple rolling elements 30 are arranged between the inner ring 10 and the outer ring 20 and are held in a rotatable position by a cage 40. The cage 40 rotatably holds each rolling element 30 with the multiple rolling elements 30 evenly arranged in the circumferential direction. The sealing member 50 is mounted on the outer ring 20 and covers the annular space between the inner ring 10 and the outer ring 20 from the axial outside.

[0054] The outer ring 20 is formed in an annular shape from a metallic material such as stainless steel or bearing steel. However, the outer ring 20 is not limited to metal and may be formed from other materials. The outer ring 20 has an outer ring body 21 whose width along the axial direction is equal to the width along the axial direction of the inner ring 10, and a projection 22 that protrudes radially inward from the outer ring body 21 and extends along the entire circumference. The projection 22 is formed in the part of the outer ring body 21 that is located in the axial center. The width of the projection 22 along the axial direction is shorter than the width of the outer ring body 21 along the axial direction and is larger than the outer diameter of the rolling element 30.

[0055] The projection 22 comprises a pair of end faces 22a facing outward in the axial direction, and an inner circumferential surface 22b (circumferential surface) connecting the inner edges of the pair of end faces 22a. Each end face 22a extends parallel to each other in both the radial and circumferential directions. An outer ring raceway surface 23 is formed on the inner circumferential surface 22b, which is recessed outward in the radial direction. The outer ring raceway surface 23 is formed in a hemispherical shape in cross-section so as to follow the outer surface of the rolling element 30, and is also formed in an annular shape that extends in the circumferential direction over the entire circumference of the inner circumferential surface 22b. The outer ring raceway surface 23 is formed on the portion of the inner circumferential surface 22b located in the axial center.

[0056] Furthermore, a recess 24 is formed on the inner circumferential surface 22b, recessed radially outward. The recess 24 is provided on the inner circumferential surface 22b at a location extending axially from the axial edge of the outer ring raceway surface 23. The recess 24 is provided above the outer ring raceway surface 23. The recess 24 is provided at an axial distance from the outer ring raceway surface 23. The recess 24 is provided at an axial distance from the upward-facing end face 22a. The recess 24 extends continuously over the entire circumferential surface. The recess 24 extends in an arc shape on the longitudinal cross-section of the rolling bearing 1. For example, on the longitudinal cross-section of the rolling bearing 1, the radius of curvature of the recess 24 may be the same as the radius of curvature of the outer ring raceway surface 23, or it may be different from the radius of curvature of the outer ring raceway surface 23. Note that the recess 24 does not have to extend with a constant curvature on the longitudinal cross-section of the rolling bearing 1. The recess 24 comprises an outward-facing surface 24a that faces in a direction inclined axially outward with respect to the radial direction (radially inward and upward, or upward), and an inward-facing surface 24b that faces in a direction inclined axially inward with respect to the radial direction (radially inward and downward, or downward). The portion of the inner circumferential surface 22b excluding the outer ring raceway surface 23 and the recess 24 extends axially with a constant inner diameter.

[0057] The inner circumferential surface 22b is provided with a ridge 25 formed on the outer ring raceway surface 23 side (axially inward) edge of the recess 24. The ridge 25 may be rounded or pointed on the longitudinal cross-section of the rolling bearing 1.

[0058] The outer ring body 21 has a pair of inner circumferential surfaces 21a that extend from the outer peripheral edge of each end face 22a of the protrusion 22 to the opening edge of the outer ring 20. The portion of each inner circumferential surface 21a located axially inward is located radially outward than the portion located axially outward.

[0059] The inner ring 10 is formed in an annular shape from a metallic material such as stainless steel or bearing steel. However, the inner ring 10 is not limited to metal and may be formed from other materials. An inner ring raceway surface 11 is formed on the outer circumferential surface of the inner ring 10, which is recessed radially inward. The inner ring raceway surface 11 is formed in a hemispherical shape in cross-section, following the outer surface of the rolling element 30, and is formed in an annular shape that extends circumferentially around the entire circumference of the outer circumferential surface. The inner ring raceway surface 11 is formed in the portion of the outer circumferential surface of the inner ring 10 that is located in the axial center, and is arranged to face the outer ring raceway surface 23 radially. The portion of the outer circumferential surface of the inner ring 10 excluding the inner ring raceway surface 11 extends axially with a constant outer diameter.

[0060] As shown in Figure 2, the multiple rolling elements 30 are formed spherically from a metallic material such as stainless steel or bearing steel. The multiple rolling elements 30 are arranged between the outer ring raceway surface 23 and the inner ring raceway surface 11 and are supported so as to be able to roll by the outer ring raceway surface 23 and the inner ring raceway surface 11. The multiple rolling elements 30 are spaced apart in the circumferential direction by a cage 40.

[0061] The retainer 40 is formed as an annular shape from a synthetic resin or metal material. The retainer 40 is positioned around a common axis O. The retainer 40 comprises an annular portion 41 that is formed in an annular shape and positioned below the plurality of rolling elements 30, and a plurality of column portions 42 that protrude upward from the annular portion 41 and are spaced apart in the circumferential direction. The column portions 42 are evenly arranged in the circumferential direction. A pair of adjacent column portions 42 in the circumferential direction form a ball pocket between them. The ball pocket penetrates the retainer 40 radially and opens upward at the upper end surface of the retainer 40. The ball pockets are provided in proportion to the number of rolling elements 30 and hold each rolling element 30 so that it can roll individually. This causes the retainer 40 to evenly arrange the rolling elements 30 with spacing in the circumferential direction. The retainer 40 is positioned with a gap between it and the inner ring 10 and the outer ring 20 so as not to interfere with the inner ring 10 and the outer ring 20. In this embodiment, the entire retainer 40 is located axially inward from the pair of end faces 22a of the projection 22 of the outer ring 20.

[0062] As shown in Figures 1 and 2, the sealing member 50 is formed in the shape of an annular plate. The sealing member 50 is positioned around a common axis O. The sealing member 50 is uniformly formed around its entire circumference. The sealing member 50 is fitted onto the outer ring 20 from the outside in the axial direction. One sealing member 50 is positioned on each side in the axial direction relative to the plurality of rolling elements 30. The sealing member 50 has an annular base portion 51 that contacts the outer ring 20 from the outside in the axial direction, an extension portion 52 that extends outward in the axial direction from the inner peripheral edge of the base portion 51, a flat portion 53 that extends radially toward the inner ring 10 from the outer axial edge of the extension portion 52, and a locking portion 54 that extends outward in both the radial and axial directions from the outer peripheral edge of the base portion 51.

[0063] As shown in Figure 2, the base portion 51 overlaps the end face 22a of the projection 22 of the outer ring 20 from the axially outward direction. The base portion 51 extends substantially parallel to the end face 22a of the projection 22 of the outer ring 20. In a plan view from the axial direction, the base portion 51 protrudes radially inward from the end face 22a of the projection 22. The distance that the base portion 51 protrudes radially inward from the end face 22a of the projection 22 is 10% or less of the radial distance between the inner ring 10 and the outer ring 20, and preferably 5% or less. The extension portion 52 extends axially outward and radially inward from the inner circumferential edge of the base portion 51. The planar portion 53 overlaps the center of the rolling element 30 in a plan view. The inner circumferential edge of the planar portion 53 is positioned with a gap between it and the outer circumferential surface of the inner ring 10. The surface of the planar portion 53 that faces inward in the axial direction is a flat surface that extends in the circumferential and radial directions. The outer edge of the locking portion 54 is locked to the inner circumferential surface 21a of the outer ring body 21 from the inside in the axial direction. As a result, the sealing member 50 is fixed to the outer ring 20 and rotates integrally with the outer ring 20 relative to the inner ring 10.

[0064] The rolling bearing 1 is filled with grease 60. The grease 60 is located between the rolling elements 30 and the sealing member 50. The grease 60 is located in the annular space between the inner ring 10 and the outer ring 20, on the same side in the axial direction as the recess 24 for the rolling elements 30. In this embodiment, the grease 60 is located on the side of the cage 40 opposite the annular portion 41, with the rolling elements 30 in between, in the axial direction. The grease 60 is located above the rolling elements 30. The grease 60 is located along the circumferential direction. The grease 60 extends in an annular or arc shape and is located coaxially with the common axis O.

[0065] The grease 60 comprises an outer ring contact portion 61 (raceway ring contact portion) that contacts the inner circumferential surface 22b of the projection 22 of the outer ring 20, and a seal member contact portion 62 that contacts the flat portion 53 of the seal member 50, located axially outward and radially inward from the outer ring contact portion 61. These outer ring contact portion 61 and seal member contact portion 62 extend circumferentially along the entire length of the grease 60. The outer ring contact portion 61 has an axial width throughout its entire circumferential direction. The outer ring contact portion 61 contacts the recess 24 of the inner circumferential surface 22b of the projection 22. The outer ring contact portion 61 contacts the recess 24 around its entire circumference. The outer ring contact portion 61 contacts the outward-facing surface 24a of the recess 24. In this case, it is desirable that the outer ring contact portion 61 also contacts at least a portion of the ridge portion 25 of the inner circumferential surface 22b. Furthermore, the outer ring contact portion 61 is in contact with the inward-facing surface 24b of the recess 24 and with the radially inward-facing portion of the recess 24. In this embodiment, the outer ring contact portion 61 is in contact with the entire recess 24. It is desirable that the grease 60 is not in contact with the outer ring 20 at any location other than the recess 24. That is, the outer ring contact portion 61 is provided at an axial distance from the contact portion between the outer ring 20 and the base portion 51 of the seal member 50. The seal member contact portion 62 has a radial width over its entire circumferential direction. The seal member contact portion 62 is in contact with the flat portion 53 at a location radially spaced from the connection portion between the extension portion 52 and the flat portion 53 of the seal member 50.

[0066] The grease 60 extends axially outward and radially inward from the outer ring contact portion 61 toward the seal member contact portion 62. The grease 60 has an inner surface 63 and an outer surface 64. The inner surface 63 connects the axially inner edge of the outer ring contact portion 61 and the radially inner edge of the seal member contact portion 62. The inner surface 63 faces the outer circumferential surface of the inner ring 10 and the rolling elements 30. The upper half of the inner surface 63 extends axially and radially inward from the radially inner edge of the seal member contact portion 62. The lower half of the inner surface 63 extends axially outward and radially inward from the axially inner edge of the outer ring contact portion 61 and connects to the lower edge of the upper half. The boundary between the upper and lower halves of the inner surface 63 forms the innermost radially inward edge of the grease 60. The inner surface 63 is spaced apart from the inner ring 10, the rolling elements 30 and the cage 40. As a result, the grease 60 is not in contact with the inner ring 10, the rolling elements 30 and the cage 40.

[0067] The outer surface 64 connects the axially outer edge of the outer ring contact portion 61 and the radially outer edge of the seal member contact portion 62. The outer surface 64 faces the inner circumferential surface 22b of the projection 22 of the outer ring 20 and the seal member 50. The outer surface 64 extends axially inward and radially outward from the radially outer edge of the seal member contact portion 62 and connects to the axially outer edge of the outer ring contact portion 61. The outer surface 64 is spaced apart from the base portion 51 and extension portion 52 of the seal member 50. As a result, the grease 60 does not come into contact with the base portion 51 and extension portion 52 of the seal member 50 that are located on the outer ring 20 side of the flat portion 53.

[0068] The grease 60 is formed such that the cross-sectional area of ​​the section along the vertical plane of the common axis O gradually increases as you move from the axially outer end towards the axially inner side. In this embodiment, the grease 60 is formed in the portion corresponding to the upper half of the inner surface 63 such that the cross-sectional area of ​​the section along the vertical plane of the common axis O gradually increases as you move from the axially outer end towards the axially inner side.

[0069] The grease 60 may come into contact with at least one of the rolling elements 30 and the retainer 40. For example, the grease 60 may initially be in a non-contact state with respect to the rolling elements 30 and the retainer 40, but may come into contact with at least one of the rolling elements 30 and the retainer 40 over time.

[0070] Next, the manufacturing method of the rolling bearing 1 of this embodiment will be described. The manufacturing method of the rolling bearing 1 of this embodiment comprises a coating step and a sealing step.

[0071] Figures 3 and 4 are longitudinal cross-sectional views of a rolling bearing illustrating a grease application method according to the first embodiment. As shown in Figure 3, the coating process is performed with the sealing member 50 not attached to the outer ring 20. That is, the annular space between the inner ring 10 and the outer ring 20 is open in the axial direction, and the grease 60 is applied with the rolling elements 30 and the cage 40 exposed. In the coating process, the nozzle A is rotated around a common axis O with respect to the outer ring 20, and the grease 60 is discharged from the nozzle A. At this time, the orientation of the nozzle A is adjusted so that the grease 60 is discharged radially outward and axially inward. Furthermore, the position of the nozzle A is adjusted so that the discharged grease 60 comes into contact with the recess 24 on the inner circumferential surface 22b of the protrusion 22 of the outer ring 20, and the grease 60 does not come into contact with the rolling elements 30 and the cage 40. Since the grease 60 is discharged while the nozzle A is rotated relative to the outer ring 20, the grease 60 applied to the outer ring 20 extends in a circumferential or arc shape. Furthermore, the grease 60 is applied in a manner that follows the discharge direction from nozzle A, protruding axially outward and radially inward from the contact portion with the outer ring 20. The axially outward end face of the applied grease 60 is formed in a convex shape that bulges outward in the axial direction.

[0072] Next, the sealing process is performed. As shown in Figure 4, in the sealing process, the sealing member 50 is brought closer to the outer ring 20 from the axial outside and attached to the outer ring 20. In the process of displacing the sealing member 50 in the axial direction, before the base portion 51 contacts the end face 22a of the protrusion 22 of the outer ring 20, the flat portion 53 of the sealing member 50 is first brought into contact with the axially outer edge of the entire grease 60 (contact process). At this time, the grease 60 is brought into contact with the radially intermediate portion of the flat portion 53. Note that the radially intermediate portion only needs to be located radially inward from the outer peripheral edge of the flat portion 53 and radially outward from the inner peripheral edge. After that, the sealing member 50 is brought further closer to the outer ring 20 and the base portion 51 is brought into contact with the end face 22a of the protrusion 22 of the outer ring 20 from the axial outside (attachment process). At this time, the flat portion 53 of the sealing member 50 pushes the grease 60 inward in the axial direction. As a result, the grease 60 is pressed against the flat portion 53 and spreads radially, forming the seal member contact portion 62 of the grease 60.

[0073] As a result, the rolling bearing 1 is formed. In this embodiment, the grease 60 is applied while the nozzle A is rotated relative to the outer ring 20 during the application process. However, the grease may also be discharged from a nozzle having a discharge hole that extends in the circumferential direction, and the grease may be applied circumferentially or in an arc shape all at once.

[0074] As described above, in this embodiment, the rolling bearing 1 has the following configuration. On the inner circumferential surface 22b of the projection 22 of the outer ring 20, there is an outer ring raceway surface 23 that supports the rolling element 30 so as to be able to roll, and a recess 24 that is provided at a location extending axially from the axial edge of the outer ring raceway surface 23 and is recessed radially. The grease 60 is in contact with the recess 24. With this configuration, the axial displacement of the grease 60 can be restricted by the recess 24. This makes it possible to suppress the grease 60 from displacing and contacting the rolling element 30 or the cage 40 by more than a desired amount. Therefore, the rotational resistance of the rolling bearing 1 can be reduced. Furthermore, since the grease 60 can be placed inside the recess 24, the total amount of grease 60 can be increased compared to a configuration in which no recess is formed. As a result, a rolling bearing 1 that can achieve both durability and reduced rotational resistance can be provided.

[0075] The grease 60 is in contact with the outward-facing surface 24a of the recess 24, which is inclined outward in the axial direction relative to the radial direction. With this configuration, the outward-facing surface 24a of the recess 24 restricts the displacement of the grease 60 inward in the axial direction from the initial state. As a result, the grease 60 is less likely to displace inward in the axial direction from its initial position during repeated use of the rolling bearing 1, so the amount of grease 60 that can be sealed in can be increased, and the above effects can be obtained more reliably.

[0076] Furthermore, since the grease 60 is in contact with the outward surface 24a of the recess 24, the shape and position of the grease 60 are less likely to change due to vibrations during transportation or long-term storage (especially storage in high-temperature environments). Therefore, it is possible to provide a rolling bearing 1 in which fluctuations in rotational resistance from the initial stages of manufacturing are suppressed.

[0077] The recess 24 has an inward-facing surface 24b that faces in a direction inclined inward in the axial direction with respect to the radial direction. With this configuration, the inward-facing surface 24b of the recess 24 restricts the displacement of the grease 60 outward in the axial direction. This prevents the grease 60 or its base oil from flowing out toward the seal member 50 and leaking out through the gap between the seal member 50 and the outer ring 20.

[0078] The grease 60 is in contact with the sealing member 50. With this configuration, when the sealing member 50 is mounted on the outer ring 20 with the grease 60 applied to the outer ring 20, even if the grease 60 in contact with the sealing member 50 is pushed inward in the axial direction by the sealing member 50, the inward displacement of the grease 60 in the axial direction is restricted by the recess 24 as described above. Therefore, it is possible to suppress the grease 60 from contacting the rolling elements 30 or the cage 40 in an amount greater than desired. Consequently, the rotational resistance of the rolling bearing 1 can be reduced.

[0079] In particular, in this embodiment, since the grease 60 is in contact with the outward-facing surface 24a of the recess 24, the grease 60 is supported not only by the recess 24 but also by the sealing member 50. Therefore, the shape and position of the grease 60 are less likely to change due to vibrations during transportation or long-term storage (especially storage in high-temperature environments). Thus, it is possible to provide a rolling bearing 1 in which fluctuations in rotational resistance from the initial stages of manufacturing are suppressed.

[0080] Furthermore, since the grease 60 is in contact with the extended portion 52 and the flat portion 53 of the sealing member 50, it is easier to suppress changes in the shape and position of the grease 60. Also, since it becomes possible to increase the amount of grease 60, higher durability can be provided to the rolling bearing 1. The above effect is achieved when the grease 60 is in contact with at least one of the extended portion 52 and the flat portion 53 of the sealing member 50. However, it is more desirable for the grease 60 to be in contact with the flat portion 53.

[0081] The recess 24 is provided at an axial distance from the outer ring raceway surface 23. This configuration prevents the grease 60 in the recess 24 from coming into contact with the rolling elements 30 that roll on the outer ring raceway surface 23. This prevents an increase in the rotational resistance of the rolling bearing 1.

[0082] The recess 24 is provided at an axial distance from the end face 22a of the protrusion 22. This configuration prevents the grease 60 or its base oil from flowing out from the recess 24 towards the end face 22a and leaking out through the gap between the end face 22a and the base portion 51 of the sealing member 50.

[0083] The recess 24 extends continuously along its entire circumferential direction. This configuration makes it difficult for the grease 60, which is arranged along the circumferential direction, to be displaced axially by the recess 24 along its entire length. Therefore, the rotational resistance of the rolling bearing 1 can be reduced. Furthermore, compared to a configuration in which the recess 24 is formed discontinuously in the circumferential direction, the amount of grease 60 arranged inside the recess 24 can be increased.

[0084] The grease 60 is in contact with the ridge 25 formed on the edge of the recess 24 on the outer ring raceway surface 23 side. With this configuration, the base oil seeping out from the grease 60 does not need to cross the ridge 25 in the process of reaching the outer ring raceway surface 23, thus preventing insufficient supply of base oil from the grease 60 to the rolling element 30.

[0085] The grease 60 has an outer ring contact portion 61 that contacts the inner circumferential surface 22b of the protrusion 22 of the outer ring 20, and a seal member contact portion 62 that contacts the flat portion 53 of the seal member 50, located axially outward and radially inward from the outer ring contact portion 61. The area of ​​the seal member contact portion 62 is larger than the contact area between the grease 60 and the extension portion 52 and the base portion 51 of the seal member 50. With this configuration, when the seal member 50 is installed after the grease 60 has been applied to a predetermined location, there is room for the grease 60, which has been pushed axially inward by the flat portion 53 of the seal member 50, to spread radially toward the extension portion 52 and the base portion 51. Therefore, it is possible to suppress the grease 60 from spreading too much toward the inner ring 10 and the rolling element 30. Thus, it is possible to easily suppress the grease 60 from directly contacting the rolling element 30 and the cage 40. Furthermore, since the sealing member 50 is provided with an extension 52 between the flat portion 53 and the base portion 51, the grease 60 can be positioned further away from the rolling element 30 compared to a configuration in which the flat portion extends radially inward from the base portion. Therefore, the amount of grease 60 can be increased. As a result, we can provide a rolling bearing 1 that achieves both durability and reduced rotational resistance.

[0086] Furthermore, the seal member contact portion 62 includes the radial center position of the grease 60 in a plan view. With this configuration, when the seal member 50 is installed, the grease 60 is pushed by the flat portion 53 and spreads radially. As a result, the seal member contact portion 62 includes the radial center position of the grease 60 in a plan view, thus preventing the grease 60 from spreading significantly inward in the axial direction toward the rolling element 30. Therefore, it is easy to prevent the grease 60 from directly contacting the rolling element 30.

[0087] The grease 60 is not in contact with the extension portion 52. With this configuration, when the sealing member 50 is installed, the grease 60, which is pushed inward in the axial direction by the flat portion 53 of the sealing member 50, can be given more room to spread radially toward the extension portion 52. As a result, it is possible to suppress the grease 60 from spreading too much toward the inner ring 10 and the rolling element 30. Thus, it is possible to easily suppress the grease 60 from coming into contact with the rolling element 30, the cage 40 and the inner ring 10 more than necessary.

[0088] The outer ring contact portion 61 is provided with an axial gap between it and the contact portion between the outer ring 20 and the base portion 51. This configuration prevents the grease 60 from coming into contact with the contact portion between the outer ring 20 and the base portion 51. This prevents the grease 60 from leaking out of the sealing member 50 through the contact portion between the outer ring 20 and the base portion 51 due to capillary action.

[0089] The grease 60 is not in contact with the base portion 51. This configuration prevents the grease 60 from coming into contact with the contact area between the outer ring 20 and the base portion 51. This prevents the grease 60 from leaking out of the sealing member 50 through the contact area between the outer ring 20 and the base portion 51 due to capillary action.

[0090] Furthermore, according to the rotating equipment 2 of this embodiment, since it is equipped with a rolling bearing 1 that achieves both durability and reduced rotational resistance, it is possible to extend the lifespan of the rotating equipment 2 and reduce power consumption of the rotating equipment 2 by reducing the rotational resistance of the shaft 3 against the housing 4.

[0091] In the first embodiment, the recess 24 extends in a curved shape on the longitudinal cross-section of the rolling bearing 1, but the configuration is not limited to this. As shown in Figure 5, the recess 24A may be formed to define a rectangular space on the longitudinal cross-section of the rolling bearing 1. In this case, the recess 24A is provided with an outward-facing surface 24Aa that faces in a direction inclined axially outward with respect to the radial direction (radially inward and upward, or upward), and an inward-facing surface 24Ab that faces in a direction inclined axially inward with respect to the radial direction (radially inward and downward, or downward). It is desirable that the grease 60 is in contact with the outward-facing surface 24Aa of the recess 24A and the ridge portion 25 of the inner circumferential surface 22b.

[0092] Furthermore, in the first embodiment, the recess 24 opens only to the inner circumferential surface 22b, but the configuration is not limited to this. As shown in Figure 6, the recess 24B may be provided without axial spacing from the upward-facing end face 22a and may open to the inner circumferential surface 22b and the upward-facing end face 22a. In this case, the recess 24B is provided with an outward-facing surface 24Ba that is inclined outward in the axial direction with respect to the radial direction (radially inward and upward, or upward). It is desirable that the grease 60 is in contact with the outward-facing surface 24Ba of the recess 24B and the ridge portion 25 of the inner circumferential surface 22b.

[0093] Furthermore, in the first embodiment, the recess 24 extends continuously over the entire circumferential direction, but the configuration is not limited to this. The recess may be formed discontinuously in the circumferential direction such that an intermittent portion is formed in at least a part of the circumferential direction.

[0094] Furthermore, in the first embodiment, the base portion 51 of the sealing member 50 protrudes radially inward from the end face 22a of the projection 22 of the outer ring 20 in a plan view. However, it is desirable that the base portion be arranged so as not to protrude radially inward from the end face 22a of the projection 22 in a plan view. With this configuration, even if the outer ring contact portion 61 of the grease 60 spreads outward in the axial direction and exceeds the inner periphery of the end face 22a, it is possible to suppress the grease 60 from adhering to the base portion. Therefore, it is possible to avoid the grease 60 coming into contact with the contact portion between the outer ring 20 and the base portion. This prevents the grease 60 from leaking to the outside of the sealing member through the contact portion between the outer ring 20 and the base portion due to capillary action.

[0095] In addition to the method of press-fitting the seal member 50 into the raceway ring (outer ring 20) as in this embodiment, there is also a method of fixing the raceway ring from the outside in the axial direction with a retaining ring such as a C-ring, but in this case the position of the seal member 50 is shifted towards the inside in the axial direction, which is undesirable. By press-fitting the seal member 50, the seal member 50 can be positioned further out in the axial direction, and the amount of grease 60 can be increased. Also, since the recess 24 can be provided further out in the axial direction, even if grease 60 is applied to the recess 24, the grease 60 is less likely to get caught in the rolling elements 30 or the raceway surface, and the rotational resistance of the rolling bearing can be reduced.

[0096] [Second Embodiment] Next, a second embodiment will be described with reference to Figure 7. The second embodiment differs from the first embodiment in that the rolling bearing 1A is equipped with grease 160 instead of grease 60 as in the first embodiment. Other than what is described below, the configuration is the same as in the first embodiment.

[0097] Figure 7 is a longitudinal cross-sectional view of a rolling bearing according to the second embodiment. As shown in Figure 7, the grease 160 is arranged along the circumferential direction. The grease 160 extends in an annular shape and is arranged coaxially with the common axis O. The grease 160 has an outer ring contact portion 161 that contacts the inner circumferential surface 22b of the projection 22 of the outer ring 20, and is not in contact with the inner ring 10, the sealing member 50, the rolling elements 30, and the cage 40. The outer ring contact portion 161 extends circumferentially along the entire length of the grease 160. The outer ring contact portion 161 has an axial width along its entire circumferential direction. The outer ring contact portion 161 is in contact with the recess 24 of the inner circumferential surface 22b of the projection 22. It is desirable that the grease 160 does not contact the outer ring 20 at any location other than the recess 24. That is, the outer ring contact portion 161 is provided at an axial distance from the contact portion between the outer ring 20 and the base portion 51 of the sealing member 50.

[0098] This embodiment provides the same effects as the first embodiment. In addition, in this embodiment, since the grease 160 is not in contact with the sealing member 50, the grease 160 is not pressed by the sealing member 50 when the sealing member 50 is mounted on the outer ring 20. This suppresses the axial inward movement of the grease 160 and prevents the grease 160 from contacting the rolling elements 30 or the cage 40 more than necessary. Therefore, an increase in the rotational resistance of the rolling bearing 1A can be suppressed.

[0099] In the second embodiment, the grease 160 extends in an annular shape, but the configuration is not limited to this. The grease may extend in an arc shape so as to form intermittent portions, or it may have a plurality of granules arranged as points around its entire circumference. If the grease has a plurality of granules, the circumferentially aligned granules may be integrated or spaced apart from each other.

[0100] [Third Embodiment] Next, a third embodiment will be described with reference to Figure 8. The rolling bearing 1B of the third embodiment differs from the rolling bearing 1A of the second embodiment in that the grease 160A is in contact with the sealing member 50 and the rolling elements 30. Other than what is described below, the configuration is the same as that of the second embodiment.

[0101] Figure 8 is a longitudinal cross-sectional view of a rolling bearing according to the third embodiment. As shown in Figure 8, the grease 160A further includes a seal member contact portion 162 that contacts the flat portion 53 of the seal member 50, located axially outside and radially inside the outer ring contact portion 161, while remaining in contact with the inner ring 10. The seal member contact portion 162 contacts only the flat portion 53 of the seal member 50. As a result, the grease 160A remains in contact with the base portion 51 and extension portion 52 of the seal member 50, which are located on the outer ring 20 side of the flat portion 53. The grease 160A is in contact with the rolling elements 30. The volume of the portion of the grease 160A that contacts the rolling elements 30 is less than half of the total volume of the grease 160A. The grease 160A may also be in contact with the retainer 40.

[0102] This embodiment provides the same effects as the second embodiment. In addition, in this embodiment, since the grease 160A is in contact with the rolling elements 30, the base oil of the grease 160A can be directly supplied to the rolling elements 30. Therefore, an increase in the rotational resistance of the rolling bearing 1B can be suppressed.

[0103] In the third embodiment, similar to the first embodiment, the grease 160A does not spread widely to the inner ring 10 and rolling element 30 when the sealing member 50 is installed. Therefore, even if the grease 160A is in contact with the rolling element 30, the contact area can be made sufficiently smaller compared to the conventional structure, thus reducing rotational resistance.

[0104] In the third embodiment, the grease 160A extends in an annular shape, but the configuration is not limited to this. The grease may extend in an arc shape so as to form intermittent portions, or it may have a plurality of granules arranged as points around its entire circumference. If the grease has a plurality of granules, the circumferentially aligned granules may be integrated or spaced apart from each other.

[0105] [Fourth Embodiment] Next, a fourth embodiment will be described with reference to Figure 9. The rolling bearing 1C of the fourth embodiment differs from the rolling bearing 1 of the first embodiment in that the grease 260 is in contact only with the outward-facing surface 24Ca of the recess 24C. Other than what is described below, the configuration is the same as that of the first embodiment.

[0106] Figure 9 is a longitudinal cross-sectional view of a rolling bearing according to the fourth embodiment. As shown in Figure 9, a recess 24C is formed on the inner circumferential surface 22b of the projection 22 of the outer ring 20, recessing radially outward. The recess 24C is provided without axial spacing from the end face 22a of the projection 22 that faces upward, and opens to the inner circumferential surface 22b and the end face 22a that faces upward. The recess 24C comprises an outward-facing surface 24Ca that faces inclined axially outward with respect to the radial direction (radially inward and upward, or upward), and a cylindrical surface 24Cc that faces radially inward. The outward-facing surface 24Ca is a concave curved surface. The cylindrical surface 24Cc extends axially and is smoothly connected to the outward-facing surface 24Ca at its axially inward edge such that a tangent line is continuous.

[0107] The grease 260 comprises an outer ring contact portion 261 (raceway ring contact portion) that contacts the inner circumferential surface 22b of the projection 22 of the outer ring 20, and a seal member contact portion 262 that contacts the seal member 50 axially outward and radially inward from the outer ring contact portion 261. The outer ring contact portion 261 contacts the recess 24C of the inner circumferential surface 22b of the projection 22. The outer ring contact portion 261 contacts the recess 24C around its entire circumference. The outer ring contact portion 261 contacts only the outward-facing surface 24Ca of the recess 24C. In this case, it is desirable that the outer ring contact portion 261 also contacts at least a part of the ridge portion 25 of the inner circumferential surface 22b. However, the outer ring contact portion 261 does not have to contact the ridge portion 25 of the inner circumferential surface 22b. In this embodiment, the seal member contact portion 262 is the portion of the grease 260 that contacts the flat portion 53 of the seal member 50. In this embodiment, the grease 260 is also in contact with the base portion 51 and the extension portion 52 of the sealing member 50. However, if the grease 260 is in contact with at least one of the base portion 51 and the extension portion 52 of the sealing member 50, it is desirable that the area of ​​the sealing member contact portion 262 is larger than the contact area between the grease 260 and the extension portion 52 and the base portion 51. The grease 260 may not be in contact with at least one of the base portion 51 and the extension portion 52. The grease 260 is formed such that the cross-sectional area of ​​the cross section along the vertical plane of the common axis O gradually increases from the axially outer end toward the axially inner end.

[0108] The grease 260 comprises a first annular portion 260a that contacts the outer ring 20, and a second annular portion 260b that is connected to the first annular portion 260a and contacts the sealing member 50. The first annular portion 260a and the second annular portion 260b are formed by applying the grease in two separate applications. The first annular portion 260a and the second annular portion 260b each extend circumferentially around a common axis O. However, at least one of the first annular portion 260a and the second annular portion 260b may extend less than 360° around the common axis O. The first annular portion 260a includes an outer ring contact portion 261. The second annular portion 260b is positioned radially opposite to the outer ring 20 (i.e., radially inward) relative to the first annular portion 260a. The second annular portion 260b is connected to and integrated with the first annular portion 260a on its axially outer side. The second annular portion 260b includes a seal member contact portion 262.

[0109] This embodiment provides the same effects as the first embodiment. In addition, in this embodiment, the recess 24C opens to the end face 22a of the upward-facing projection 22, and the grease 260 is in contact only with the outward-facing surface 24Ca of the recess 24C. This configuration prevents the grease 260 or its base oil from flowing out from the recess 24C towards the end face 22a and leaking out through the gap between the end face 22a and the base portion 51 of the sealing member 50.

[0110] In the fourth embodiment, the first annular portion 260a and the second annular portion 260b extend in a circular shape, but the configuration is not limited to this. At least one of the first annular portion and the second annular portion may be provided with granular bodies arranged in a point-like manner around its entire circumference. In this case, the multiple granular bodies aligned in the circumferential direction may be integrated or spaced apart from each other.

[0111] Furthermore, in the fourth embodiment, the grease 260 has a first annular portion 260a and a second annular portion 260b, but the configuration is not limited to this. As shown in Figure 10, the grease 260A may be formed by a single annular portion having an outer ring contact portion 261 and a seal member contact portion 262.

[0112] [Fifth Embodiment] Next, a fifth embodiment will be described with reference to Figure 11. The rolling bearing 1D of the fifth embodiment differs from the rolling bearing 1 of the first embodiment in that the grease 360 ​​is arranged axially along the recess 24D. Other than what is described below, the configuration is the same as that of the first embodiment.

[0113] Figure 11 is a longitudinal cross-sectional view of a rolling bearing according to the fifth embodiment. As shown in Figure 11, a recess 24D is formed on the inner circumferential surface 22b of the projection 22 of the outer ring 20, recessing radially outward. The recess 24D is provided without axial spacing from the end face 22a of the upward-facing projection 22 and opens to the inner circumferential surface 22b and the upward-facing end face 22a. The recess 24D comprises an outward-facing surface 24Da that faces inclined radially outward with respect to the radial direction (radially inward and upward, or upward) and a cylindrical surface 24Dc that faces radially inward. The outward-facing surface 24Da is a concave curved surface. The cylindrical surface 24Dc extends axially and is smoothly connected to the outward-facing surface 24Da at its axially inward edge such that the tangent is continuous. The recess 24D extends axially on the longitudinal cross-section of the rolling bearing 1D such that its axial width is greater than its radial depth. The outward-facing surface may be a flat surface facing outward in the axial direction, or a conical surface facing outward in the axial direction and inward in the radial direction.

[0114] The grease 360 ​​includes an outer ring contact portion 361 that contacts the inner circumferential surface 22b of the projection 22 of the outer ring 20. The outer ring contact portion 361 contacts the recess 24D of the inner circumferential surface 22b of the projection 22. The outer ring contact portion 361 is in contact with the recess 24D around its entire circumference. The outer ring contact portion 361 is in contact with the outward-facing surface 24Da and the cylindrical surface 24Dc of the recess 24D. The outer ring contact portion 361 is also in contact with at least a portion of the ridge 25 of the inner circumferential surface 22b. The grease 360 ​​is in contact with the sealing member 50. In this embodiment, the grease 360 ​​is in contact with the base portion 51 and the extension portion 52 of the sealing member 50.

[0115] The grease 360 ​​is arranged axially along the recess 24D on the longitudinal section of the rolling bearing 1D. The grease 360 ​​comprises a first annular portion 360a, a second annular portion 360b, and a third annular portion 360c, which are aligned axially. The first annular portion 360a, the second annular portion 360b, and the third annular portion 360c are formed by applying the grease in three separate steps. The first annular portion 360a, the second annular portion 360b, and the third annular portion 360c each extend circumferentially around a common axis O. However, at least one of the first annular portion 360a, the second annular portion 360b, and the third annular portion 360c may extend less than 360° around the common axis O. The first annular portion 360a is in contact with the outward-facing surface 24Da and the cylindrical surface 24Dc of the recess 24D. The second annular portion 360b is connected to the first annular portion 360a on its axially outward side. The second annular portion 360b is in contact with the cylindrical surface 24Dc of the recess 24D. The third annular portion 360c is connected to the second annular portion 360b on its axially outward side. The third annular portion 360c is in contact with the cylindrical surface 24Dc of the recess 24D and the sealing member 50.

[0116] This embodiment provides the same effects as the first embodiment. In addition, in this embodiment, since the grease 360 ​​is arranged axially along the recess 24D, the recess 24D can effectively restrict the axial displacement of the grease 360, thereby suppressing the grease 360 ​​from displacing and contacting the rolling element 30 or the cage 40 by an amount greater than desired. Furthermore, the shape and position of the grease 360 ​​are less likely to change due to vibrations during transportation or long-term storage (especially storage in high-temperature environments). Therefore, a rolling bearing 1D is provided in which fluctuations in rotational resistance from the initial stages of manufacturing are suppressed.

[0117] In the fifth embodiment, the first annular portion 360a, the second annular portion 360b, and the third annular portion 360c extend in a circular shape, but the configuration is not limited to this. At least one of the first annular portion, the second annular portion, and the third annular portion may be equipped with granular bodies arranged in a point-like manner around its entire circumference. In this case, the multiple granular bodies aligned in the circumferential direction may be integrated or spaced apart from one another.

[0118] Furthermore, in the fifth embodiment, the grease 360 ​​has a first annular portion 360a, a second annular portion 360b, and a third annular portion 360c, but the configuration is not limited to this. As shown in Figure 12, the grease 360A may extend axially along the recess 24D on the longitudinal cross-section of the rolling bearing 1D.

[0119] Furthermore, in the fifth embodiment, the grease 360 ​​is in contact with the ridge portion 25 of the inner circumferential surface 22b of the projection 22 of the outer ring 20, but the configuration is not limited to this. As shown in Figure 13, the grease 360B may not be in contact with the ridge portion 25. In this case, the first annular portion 360a may be formed smaller on the longitudinal cross-section of the rolling bearing 1D than the second annular portion 360b and the third annular portion 360c so as not to contact the ridge portion 25. With this configuration, although the supply of base oil of the grease 360B to the rolling elements 30 may be insufficient, the total amount of grease 360B can be increased, thereby providing the rolling bearing 1D with higher durability.

[0120] [Sixth Embodiment] Next, the sixth embodiment will be described with reference to Figure 14. The rolling bearing 1E of the sixth embodiment differs from the rolling bearing 1 of the first embodiment in that the deepest part of the recess 24E in the radial direction is formed axially inward from the axial midpoint of the recess 24E. Other than what is described below, the configuration is the same as that of the first embodiment.

[0121] Figure 14 is a longitudinal cross-sectional view of a rolling bearing according to the sixth embodiment. As shown in Figure 14, the recess 24E is provided at an axial distance from the outer ring raceway surface 23. The recess 24E is provided at an axial distance from the upward-facing end face 22a. The recess 24E is formed on the longitudinal cross-section of the rolling bearing 1E such that its axial width is greater than its radial depth. The recess 24E comprises an outward-facing surface 24Ea that faces in a direction inclined axially outward with respect to the radial direction (radially inward and upward, or upward), an inward-facing surface 24Eb that faces in a direction inclined axially inward with respect to the radial direction (radially inward and downward, or downward), and a cylindrical surface 24Ec that faces radially inward. In this embodiment, the outward-facing surface 24Ea and the inward-facing surface 24Eb face axially. As a result, the recess 24E is formed in a rectangular shape on the longitudinal cross-section of the rolling bearing 1E. The cylindrical surface 24Ec is located at the deepest point in the radial direction of the recess 24E and axially straddles the axial midpoint of the recess 24E. As a result, the deepest point in the radial direction of the recess 24E is formed axially inward from the axial midpoint of the recess 24E.

[0122] The grease 460 comprises an outer ring contact portion 461 (raceway ring contact portion) that contacts the inner circumferential surface 22b of the projection 22 of the outer ring 20, and a seal member contact portion 462 that contacts the flat portion 53 of the seal member 50 axially outward and radially inward from the outer ring contact portion 461. The outer ring contact portion 461 is in contact with the recess 24E of the inner circumferential surface 22b of the projection 22. The outer ring contact portion 461 is in contact with the recess 24E over its entire circumference. The outer ring contact portion 461 is in contact with the outward-facing surface 24Ea and the cylindrical surface 24Ec of the recess 24E. The outer ring contact portion 461 is also in contact with at least a portion of the ridge portion 25 of the inner circumferential surface 22b. The grease 460 is not in contact with the inward-facing surface 24Eb of the recess 24E. However, the grease 460 may be in contact with the inward-facing surface 24Eb of the recess 24E. In this embodiment, the seal member contact portion 462 is the portion of the grease 460 that contacts the flat portion 53 of the seal member 50. In this embodiment, the grease 460 does not contact the base portion 51 and the extension portion 52 of the seal member 50. However, the grease 460 may contact at least one of the base portion 51 and the extension portion 52 of the seal member 50, in which case it is desirable that the area of ​​the seal member contact portion 462 is larger than the contact area between the grease 260 and the extension portion 52 and the base portion 51. The grease 460 extends axially outward and radially inward from the outer ring contact portion 461 toward the seal member contact portion 462.

[0123] This embodiment provides the same effects as the first embodiment. In addition, in this embodiment, the deepest part of the recess 24E in the radial direction is formed axially inward from the axial midpoint of the recess 24E. With this configuration, when discharging grease 460 from the nozzle and applying it to a predetermined location, the tip of the nozzle can be inserted from the outside of the rolling bearing 1E into the inside of the outer ring 20 and inner ring 10, bringing it closer to the recess 24E. Therefore, productivity can be improved for small-diameter rolling bearings 1E. Also, since the nozzle can be brought closer to the recess 24E, grease 460 can be applied with precision, and it is possible to suppress grease 460 from contacting the rolling elements 30 and the like in excess of a desired amount. Therefore, the rotational resistance of the rolling bearing 1E can be reduced.

[0124] In the sixth embodiment, the recesses 24E are formed symmetrically on the vertical cross-section of the rolling bearing 1E, but the configuration is not limited to this. As shown in Figures 15 and 16, the recesses 124E and 224E may be formed asymmetrically on the vertical cross-section of the rolling bearing 1E. The following describes the modified examples shown in Figures 15 and 16.

[0125] In the first modified example shown in Figure 15, the recess 124E is formed on the longitudinal cross-section of the rolling bearing 1E such that its axial width is greater than its radial depth. The recess 124E comprises an outward-facing surface 124Ea that faces in a direction inclined axially outward with respect to the radial direction (radially inward and upward, or upward) and an inward-facing surface 124Eb that faces in a direction inclined axially inward with respect to the radial direction (radially inward and downward, or downward). The outward-facing surface 124Ea is a curved surface that is recessed axially inward and radially outward. The inward-facing surface 124Eb is a conical surface that extends axially outward and radially inward from the axially outward edge of the outward-facing surface 124Ea. The connection between the outward-facing surface 124Ea and the inward-facing surface 124Eb is located axially inward from the axial midpoint of the recess 124E. As a result, the deepest point of the recess 124E in the radial direction is formed axially inward from the axial midpoint of the recess 124E.

[0126] The grease 460A comprises an outer ring contact portion 461A (raceway ring contact portion) that contacts the inner circumferential surface 22b of the projection 22 of the outer ring 20, and a seal member contact portion 462A that contacts the flat portion 53 of the seal member 50 axially outward and radially inward from the outer ring contact portion 461A. The outer ring contact portion 461A is in contact with the recess 124E of the inner circumferential surface 22b of the projection 22. The outer ring contact portion 461A is in contact with the recess 124E over its entire circumference. The outer ring contact portion 461A is in contact with the outward surface 124Ea of the recess 124E. The outer ring contact portion 461A is in contact with the inward surface 124Eb of the recess 124E. The outer ring contact portion 461A is in contact with the connection between the outward surface 124Ea and the inward surface 124Eb of the recess 124E. The grease 460A is not in contact with the ridges 25 of the inner circumferential surface 22b. However, the grease 460A may be in contact with the ridges 25 of the inner circumferential surface 22b.

[0127] In this modified example, the seal member contact portion 462A is the portion of the grease 460A that contacts the flat portion 53 of the seal member 50. In this modified example, the grease 460A does not contact the base portion 51 and the extension portion 52 of the seal member 50. However, the grease 460A may contact at least one of the base portion 51 and the extension portion 52 of the seal member 50, in which case it is desirable that the area of ​​the seal member contact portion 462A is larger than the contact area between the grease 460A and the extension portion 52 and the base portion 51. The grease 460A may be formed such that the cross-sectional area of ​​the cross section along the vertical plane of the common axis O gradually increases from the axially outer end toward the axially inner side. The grease 460A extends axially outward and radially inward from the outer ring contact portion 461A toward the seal member contact portion 462A. The grease 460A extends from the outer ring contact portion 461A along the inward surface 124Eb of the recess 124E.

[0128] In the second modified example shown in Figure 16, the recess 224E is formed such that its axial width is greater than its radial depth on the longitudinal cross-section of the rolling bearing 1E. The recess 224E comprises an outward-facing surface 224Ea that faces inclined axially outward with respect to the radial direction (radially inward and upward, or upward) and an inward-facing surface 224Eb that faces inclined axially inward with respect to the radial direction (radially inward and downward, or downward). The outward-facing surface 224Ea is a plane facing axially outward. The inward-facing surface 224Eb is a conical surface extending axially outward and radially inward from the radially outward edge of the outward-facing surface 224Ea. The connection between the outward-facing surface 224Ea and the inward-facing surface 224Eb is located axially inward from the axial midpoint of the recess 224E. As a result, the deepest point of the recess 224E in the radial direction is formed axially inward from the axial midpoint of the recess 224E.

[0129] The grease 460B comprises an outer ring contact portion 461B (raceway ring contact portion) that contacts the inner circumferential surface 22b of the projection 22 of the outer ring 20, and a seal member contact portion 462B that contacts the flat portion 53 of the seal member 50 axially outward and radially inward from the outer ring contact portion 461B. The outer ring contact portion 461B is in contact with the recess 224E of the inner circumferential surface 22b of the projection 22. The outer ring contact portion 461B is in contact with the recess 224E over its entire circumference. The outer ring contact portion 461B is in contact with the outward-facing surface 224Ea of the recess 224E. The outer ring contact portion 461B is in contact with the inward-facing surface 224Eb of the recess 224E. The outer ring contact portion 461B is not in contact with the connection between the outward-facing surface 224Ea and the inward-facing surface 224Eb of the recess 224E. The grease 460B is not in contact with the ridges 25 of the inner circumferential surface 22b. However, the grease 460B may be in contact with the ridges 25 of the inner circumferential surface 22b.

[0130] In this modified example, the seal member contact portion 462B is the portion of the grease 460B that contacts the flat portion 53 of the seal member 50. In this modified example, the grease 460B does not contact the base portion 51 and the extension portion 52 of the seal member 50. However, the grease 460B may contact at least one of the base portion 51 and the extension portion 52 of the seal member 50, in which case it is desirable that the area of ​​the seal member contact portion 462B is larger than the contact area between the grease 460B and the extension portion 52 and the base portion 51. The grease 460B may be formed such that the cross-sectional area of ​​the cross section along the vertical plane of the common axis O gradually increases from the axially outer end toward the axially inner. The grease 460B extends axially outward and radially inward from the outer ring contact portion 461B toward the seal member contact portion 462B. The grease 460B extends from the outer ring contact portion 461B along the inward surface 224Eb of the recess 224E.

[0131] Even these modified rolling bearings 1E produce the same effects as the sixth embodiment.

[0132] [Seventh Embodiment] Next, the seventh embodiment will be described with reference to Figure 17. The rolling bearing 1F of the seventh embodiment differs from the rolling bearing 1 of the first embodiment in the shape of the inner circumferential surface 22b of the protrusion 22 of the outer ring 20. Other than what is described below, the configuration is the same as that of the first embodiment.

[0133] Figure 17 is a longitudinal cross-sectional view of a rolling bearing according to the seventh embodiment. As shown in Figure 17, the inner circumferential surface 22b of the projection 22 of the outer ring 20 has a recess 24 and a connecting surface 26. The recess 24 is provided at an axial distance from the upward-facing end face 22a of the projection 22. The connecting surface 26 is formed between the recess 24 and the upward-facing end face 22a of the projection 22. The connecting surface 26 extends axially and faces radially inward. The connecting surface 26 is located radially outward from the axial edge of the outer ring raceway surface 23, away from the inner ring 10.

[0134] This embodiment provides the same effects as the first embodiment. In addition, in this embodiment, the inner circumferential surface 22b of the projection 22 of the outer ring 20 has a connecting surface 26 formed between the recess 24 and the end face 22a. The connecting surface 26 is located radially outward from the axial edge of the outer ring raceway surface 23 in the radial direction. With this configuration, when inserting the tip of the nozzle from the outside of the rolling bearing 1F into the inside of the outer ring 20 and inner ring 10 in order to discharge grease 60 from the nozzle and apply it to a predetermined location, the connecting surface 26 is less likely to come into contact with the nozzle. Therefore, it is easier to bring the nozzle closer to the recess 24 when applying grease 60, thereby improving productivity in small-diameter rolling bearings 1F. Also, because it is easier to bring the nozzle closer to the recess 24, grease 60 can be applied with precision, and it is possible to suppress grease 60 from coming into contact with the rolling elements 30 or the like in excess of a desired amount. Thus, the rotational resistance of the rolling bearing 1F can be reduced.

[0135] [Eighth Embodiment] Next, the eighth embodiment will be described with reference to Figure 18. The rolling bearing 1G of the eighth embodiment differs from the rolling bearing 1 of the first embodiment in the shape of the inner circumferential surface 22b of the protrusion 22 of the outer ring 20. Other than what is described below, the configuration is the same as that of the first embodiment.

[0136] Figure 18 is a longitudinal cross-sectional view of a rolling bearing according to the eighth embodiment. As shown in Figure 18, the inner circumferential surface 22b of the projection 22 of the outer ring 20 has a recess 224 and an inclined portion 227. The recess 224 is provided without axial spacing from the upward-facing end face 22a of the projection 22 and opens to the inner circumferential surface 22b and the upward-facing end face 22a. The recess 224 comprises an outward-facing surface 224a that faces in an axially outward direction with respect to the radial direction (radially inward and upward, or upward) and a cylindrical surface 224c that faces radially inward. The outward-facing surface 224a is a concave curved surface. The radially inward edge of the outward-facing surface 224a is located radially outward from the axial edge of the outer ring raceway surface 23 in the radial direction. The cylindrical surface 224c extends axially and connects to the axially outward edge of the outward-facing surface 224a. The inclined portion 227 extends from the edge of the recess 224 on the outer ring raceway surface 23 side (the radially inner edge of the outward-facing surface 224a) inclined radially and axially toward the outer ring raceway surface 23. That is, the inclined portion 227 extends radially inward and axially inward from the ridge portion 25 of the inner circumferential surface 22b. In this embodiment, the inclined portion 227 extends linearly from the edge of the recess 224 on the longitudinal cross-section of the rolling bearing 1G. However, the inclined portion only needs to extend with a steeper radial inclination than the recess 224, with respect to the connection between the inclined portion and the recess 224 on the longitudinal cross-section of the rolling bearing 1G. The inclined portion 227 is provided at an axial distance from the outer ring raceway surface 23.

[0137] The grease 560 includes an outer ring contact portion 561 that contacts the inner circumferential surface 22b of the projection 22 of the outer ring 20. The outer ring contact portion 561 contacts the recess 224 of the inner circumferential surface 22b of the projection 22. The outer ring contact portion 561 is in contact with the recess 224 around its entire circumference. The outer ring contact portion 561 is in contact with the outward-facing surface 224a and the cylindrical surface 224c of the recess 224. The outer ring contact portion 561 is also in contact with at least a portion of the ridge portion 25 of the inner circumferential surface 22b. It is desirable that the outer ring contact portion 561 is not in contact with the inclined portion 227. The grease 560 may also be in contact with the sealing member 50.

[0138] This embodiment provides the same effects as the first embodiment. In addition, in this embodiment, the inner circumferential surface 22b of the projection 22 of the outer ring 20 has an inclined portion 227 that extends toward the outer ring raceway surface 23 from the edge of the recess 224 on the outer ring raceway surface 23 side, inclined radially and axially. With this configuration, even if the end of the recess 224 on the outer ring raceway surface 23 side extends radially, the inner circumferential surface 22b gradually inclins toward the outer ring raceway surface 23 from the recess 224, thereby promoting the flow of base oil seeping from the grease 560 from the recess 224 along the inclined portion 227 toward the outer ring raceway surface 23. Therefore, even if the grease 560 is not positioned close to the outer ring raceway surface 23, insufficient supply of base oil of the grease 560 to the rolling element 30 can be suppressed.

[0139] Furthermore, as shown in Figure 19, the grease 560A may be arranged so as not to protrude radially from the inside of the recess 224 toward the inclined portion 227 side (inward). In other words, the grease 560A may be arranged so as not to be located within the formation range of the inclined portion 227 in the radial direction. This configuration makes it possible to suppress contact between the grease 560A and the rolling element 30. On the other hand, since the amount of grease 560A applied is reduced, it is possible to suitably obtain the effect of suppressing insufficient supply of the base oil of the grease 560A to the rolling element 30 as described above.

[0140] In the eighth embodiment, the recess 224 is provided without any axial gap with respect to the upward-facing end face 22a of the protruding portion 22, but the configuration is not limited to this. That is, as shown in Figure 20, the recess 224A may be provided with an axial gap with respect to the upward-facing end face 22a. In the illustrated example, the recess 224A includes an outward-facing surface 224Aa that is inclined outward in the axial direction with respect to the radial direction, and an inward-facing surface 224Ab that is inclined inward in the axial direction with respect to the radial direction, but the shape of the recess is not particularly limited.

[0141] It should be noted that the present invention is not limited to the embodiments described above with reference to the drawings, and various modifications are conceivable within its technical scope. For example, in the above embodiment, the inner ring 10 is provided as a rotating ring, and the outer ring 20 is provided as a stationary ring. The greases 60, 160, 160A, 260, 260A, 360, 360A, 360B, 460, 460A, 460B, 560, and 560A are in contact with the stationary outer ring 20. However, the raceway rings that the grease contacts do not have to be stationary rings. That is, the inner ring may be provided as a stationary ring, the outer ring as a rotating ring, and the grease may be in contact with the stationary inner ring. Alternatively, the inner ring may be provided as a stationary ring, the outer ring as a rotating ring, and the grease may be in contact with the rotating outer ring.

[0142] Furthermore, in each of the above embodiments, the greases 60, 160, 160A, 260, 260A, 360, 360A, 360B, 460, 460A, 460B, 560, and 560A are in contact with the recess over its entire circumference, but the configuration is not limited to this. The grease may be in contact with only a portion of the recess in the circumferential direction.

[0143] Furthermore, in the above embodiment, the greases 60, 160, and 160A are not in contact with the base portion 51 and extension portion 52 of the sealing member 50, but the configuration is not limited to this. The grease may be in contact with at least one of the base portion 51 and extension portion 52 of the sealing member 50, as long as the area of ​​the contact portion with the sealing member is larger than the contact area between the grease and the extension portion 52 and the base portion 51.

[0144] Furthermore, in the above embodiment, the greases 60, 160, 160A, 260, 260A, 360, 360A, 360B, 460, 460A, 460B, 560, and 560A are not in contact with the inner ring 10 and the retainer 40, but the configuration is not limited to this. As described above, in the above embodiment, when the sealing member 50 is installed, it is possible to suppress the grease from spreading widely to the inner ring 10 side and the rolling element 30 side. Therefore, even if the grease comes into contact with at least one of the inner ring 10 and the retainer 40, the contact area can be made sufficiently smaller compared to the conventional structure, so that the effect of reducing rotational resistance can be obtained.

[0145] Furthermore, the rolling bearing may be equipped with greases other than greases 60, 160, 160A, 260, 260A, 360, 360A, 360B, 460, 460A, 460B, 560, and 560A. In the above embodiment, the grease is arranged on the side of the cage 40 opposite to the annular portion 41, sandwiching the rolling elements 30 in the axial direction, but the grease may also be arranged on the side of the cage 40 that is on the annular portion 41 relative to the rolling elements 30 in the axial direction. For example, the rolling bearing may further be equipped with grease applied to the grease pockets or lower end surface of the cage.

[0146] Furthermore, although a fan motor was used as an example of a rotating device in the above embodiment, the rotating device is not limited to this. For example, the present invention may be applied to dental handpieces, spindle motors of hard disk drives, and the like as rotating devices.

[0147] Furthermore, without departing from the spirit of the present invention, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described embodiments and their variations may be combined as appropriate. [Explanation of symbols]

[0148] 1, 1A, 1B, 1C, 1D, 1E, 1F, 1G…Bearing 2…Rotating equipment 10…Inner ring (other raceway ring) 20…Outer ring (one raceway ring) 22…Protrusion 22a…End face 22b…Inner circumferential surface (circumferential surface) 23…Outer ring raceway surface (raceway surface) 24, 24A, 24B, 24C, 24D, 24E, 124E, 224, 224A, 224E…Recess 25…Ridge 26…Connecting surface 30…Rolling element 50…Sealing member 51…Base 52…Extension 53…Flat surface 60, 160, 160A, 260, 260A, 360, 360A, 360B, 460, 460A, 460B, 560, 560A…Grease 61, 161, 261, 361, 461, 461A, 461B, 561... Outer ring contact area (raceway ring contact area) 62, 162, 262, 462, 462A, 462B... Seal member contact area 227... Inclined section

Claims

1. The inner and outer rings are arranged coaxially with each other, A rolling element disposed between the inner ring and the outer ring, A retainer for holding the rolling element, A sealing member mounted on the inner ring or the outer ring, covering the space between the inner ring and the outer ring from the outside in the axial direction, Grease disposed between the rolling element and the sealing member, Equipped with, One of the inner and outer raceways has a circumferential surface facing the other raceway. The aforementioned circumferential surface has, A raceway surface that supports the rolling element so that it can roll, A recess is provided at a location extending in the axial direction from the axial edge of the raceway surface, and is radially recessed, A portion extending axially with a constant inner diameter from the axial edge of the raceway surface toward the recess, Formed, The grease is in contact with the recess and the sealing member, and is not in contact with the other raceway wheel, the rolling element and the retainer. The recess has a portion that faces in a direction inclined inward in the axial direction with respect to the radial direction. Rolling bearings.

2. The grease is in contact with a portion of the recess that is inclined outward in the axial direction with respect to the radial direction. The rolling bearing according to claim 1.

3. The recess is provided at an interval in the axial direction from the raceway surface. The rolling bearing according to claim 1.

4. One of the raceways has a projection that protrudes toward the other raceway and has the circumferential surface formed thereon. The projection has an end face that faces outward in the axial direction and connects to the circumferential surface at the periphery on the other raceway side. The recess is provided at an interval in the axial direction relative to the end face. The rolling bearing according to claim 1.

5. The recess extends continuously over the entire circumferential direction. The rolling bearing according to claim 1.

6. One of the raceways has a projection that protrudes toward the other raceway and has the circumferential surface formed thereon. The projection has an end face that faces outward in the axial direction and connects to the circumferential surface at the periphery on the other raceway side. The circumferential surface has a connecting surface formed between the recess and the end face, The connecting surface is located further away from the other raceway ring than the axial edge of the raceway surface in the radial direction. The rolling bearing according to claim 1.

7. An inner ring and an outer ring arranged coaxially with respect to each other, A rolling element disposed between the inner ring and the outer ring, A retainer for holding the rolling element, A sealing member mounted on the inner ring or the outer ring, covering the space between the inner ring and the outer ring from the outside in the axial direction, Grease disposed between the rolling element and the sealing member, Equipped with, One of the inner and outer raceways has a circumferential surface facing the other raceway. The aforementioned circumferential surface has, A raceway surface that supports the rolling element so that it can roll, A recess is provided at a location extending in the axial direction from the axial edge of the raceway surface, and is radially recessed, A portion extending axially with a constant inner diameter from the axial edge of the raceway surface toward the recess, Formed, The grease is in contact with the ridge formed on the edge of the recess on the raceway surface side and with the sealing member, and is not in contact with the other raceway wheel, the rolling element and the retainer. One of the raceways has a projection that protrudes toward the other raceway and has the circumferential surface formed thereon. The projection has an end face that faces outward in the axial direction and connects to the circumferential surface at the periphery on the other raceway side. The circumferential surface has a connecting surface formed between the recess and the end face, The connecting surface is located further away from the other raceway ring than the axial edge of the raceway surface in the radial direction. Rolling bearings.

8. The circumferential surface has an inclined portion that extends toward the raceway surface from the edge of the recess on the raceway surface side, inclined in the radial and axial directions. The rolling bearing according to claim 1.

9. An inner ring and an outer ring arranged coaxially with respect to each other, A rolling element disposed between the inner ring and the outer ring, A retainer for holding the rolling element, A sealing member mounted on the inner ring or the outer ring, covering the space between the inner ring and the outer ring from the outside in the axial direction, Grease disposed between the rolling element and the sealing member, Equipped with, One of the inner and outer raceways has a circumferential surface facing the other raceway. The aforementioned circumferential surface has, A raceway surface that supports the rolling element so that it can roll, A recess is provided at a location extending in the axial direction from the axial edge of the raceway surface, and is radially recessed, A portion extending axially with a constant inner diameter from the axial edge of the raceway surface toward the recess, Formed, The grease is in contact with the ridge formed on the edge of the recess on the raceway surface side and with the sealing member, and is not in contact with the other raceway wheel, the rolling element and the retainer. The circumferential surface has an inclined portion that extends toward the raceway surface from the edge of the recess on the raceway surface side, inclined in the radial and axial directions. Rolling bearings.

10. The grease is arranged so as not to protrude from the inside of the recess toward the inclined portion in the radial direction. A rolling bearing according to claim 8 or claim 9.

11. The sealing member is An annular base portion that contacts one of the raceways from the outside in the axial direction, An extension portion extending outward in the axial direction from the periphery of the other raceway wheel side of the base portion, A planar portion extending radially from the outer edge in the axial direction of the extension toward the other raceway ring, It has, The aforementioned grease is The raceway contact portion that contacts the circumferential surface of one of the raceway rings, A seal member contact portion that is located axially outward from the aforementioned raceway contact portion and in contact with the flat portion on the other raceway side, It has, The area of ​​the contact portion of the sealing member is larger than the contact area between the grease and the extended portion and the base portion of the sealing member. The rolling bearing according to claim 1.

12. An inner ring and an outer ring arranged coaxially with respect to each other, A rolling element disposed between the inner ring and the outer ring, A retainer for holding the rolling element, A sealing member mounted on the inner ring or the outer ring, covering the space between the inner ring and the outer ring from the outside in the axial direction, Grease disposed between the rolling element and the sealing member, Equipped with, One of the inner and outer raceways has a circumferential surface facing the other raceway. The aforementioned circumferential surface has, A raceway surface that supports the rolling element so that it can roll, A recess is provided at a location extending in the axial direction from the axial edge of the raceway surface, and is radially recessed, A portion extending axially with a constant inner diameter from the axial edge of the raceway surface toward the recess, Formed, The grease is in contact with the ridge formed on the edge of the recess on the raceway surface side and with the sealing member, and is not in contact with the other raceway wheel, the rolling element and the retainer. The sealing member is An annular base portion that contacts one of the raceways from the outside in the axial direction, An extension portion extending outward in the axial direction from the periphery of the other raceway wheel side of the base portion, A planar portion extending radially from the outer edge in the axial direction of the extension toward the other raceway ring, It has, The aforementioned grease is The raceway contact portion that contacts the circumferential surface of one of the raceway rings, A seal member contact portion that is located axially outward from the aforementioned raceway contact portion and in contact with the flat portion on the other raceway side, It has, The area of ​​the contact portion of the sealing member is larger than the contact area between the grease and the extended portion and the base portion of the sealing member. Rolling bearings.

13. The seal member contact portion includes the radial center position in the grease when viewed from the axial direction. A rolling bearing according to claim 11 or claim 12.

14. The grease is in non-contact with the extension portion. A rolling bearing according to claim 11 or claim 12.

15. The aforementioned raceway contact portion is provided with an axial gap between it and the contact portion between one of the raceway wheels and the base portion. A rolling bearing according to claim 11 or claim 12.

16. The grease is in non-contact with the base portion. A rolling bearing according to claim 11 or claim 12.

17. The aforementioned one raceway has a projection that protrudes toward the other raceway and on which the raceway surface is formed, The aforementioned projection faces outward in the axial direction and connects to the circumferential surface at the periphery on the other raceway side, and has an end face that contacts the base portion. The base portion is positioned so as to not protrude beyond the end face toward the other raceway wheel when viewed from the axial direction. A rolling bearing according to claim 11 or claim 12.

18. A rotating body arranged to be rotatable, A support that rotatably supports the aforementioned rotating body, A rolling bearing according to claim 1, claim 7, claim 9, or claim 12 is interposed between the rotating body and the support, A rotating device equipped with the following features.

19. The inner and outer rings are arranged coaxially with each other, A rolling element disposed between the inner ring and the outer ring, A retainer for holding the rolling element, A sealing member mounted on the inner ring or the outer ring, covering the space between the inner ring and the outer ring from the outside in the axial direction, Grease disposed between the rolling element and the sealing member, Equipped with, One of the inner and outer raceways has a circumferential surface facing the other raceway. The aforementioned circumferential surface has, A raceway surface that supports the rolling element so that it can roll, A recess is provided at a location extending in the axial direction from the axial edge of the raceway surface, and is radially recessed, A portion extending axially with a constant inner diameter from the axial edge of the raceway surface toward the recess, Formed, The recess has a portion that faces in a direction inclined inward in the axial direction with respect to the radial direction, The sealing member is An annular base portion that contacts one of the raceways from the outside in the axial direction, An extension extending outward in the axial direction from the peripheral edge of the inner ring and the other outer ring of the base portion, A planar portion extending radially from the outer edge in the axial direction of the extension toward the other raceway ring, A method for manufacturing a rolling bearing having, The application step involves bringing the grease into contact with the recess and applying the grease so that it protrudes from the contact portion with one raceway ring outwards in the axial direction and toward the other raceway ring, A contact step in which the sealing member is brought close to one of the raceways from the outside in the axial direction, and the flat portion is brought into contact with the outer edge in the axial direction of the grease, After the contact step, the sealing member is brought close to the one raceway, the base portion is brought into contact with the one raceway from the outside in the axial direction, and the grease is pushed inward in the axial direction by the flat portion. A method for manufacturing rolling bearings that includes [a specific feature / feature].

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