Rolling bearing, rotating apparatus, and rolling bearing manufacturing method

Abstract

Provided is a rolling bearing capable of ensuring durability and reducing rotational resistance at the same time. A rolling bearing (1) is provided with: an inner ring (10) and an outer ring (20) disposed coaxially with each other; rolling bodies (30) disposed between the inner ring (10) and the outer ring (20); a seal member (50) that is attached to the outer ring (20) and covers the space between the inner ring (10) and the outer ring (20) from the outside in the axial direction; and grease (60) disposed between the rolling body (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 formed with: an outer ring raceway surface (23) that supports the rolling elements (30) so as to be able to roll; and a recess (24) which is provided at a location extending in the axial direction from an end edge of the outer ring raceway surface (23) in the axial direction and which is recessed in the radial direction. The grease (60) is in contact with the recess (24). The non-mixing consistency of the grease (60) is greater than 178 and less than 287.

Description

Technical Field

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

[0002] Conventionally, there are rolling bearings that retain grease between a pair of raceways (inner and outer rings). In such rolling bearings, the resistance of the grease sometimes becomes the main reason for the increase in rotational resistance. However, in rolling bearings, it is desirable to reduce rotational resistance for the purpose of saving power in the rotating equipment carried. In particular, there is a strong demand for reducing rotational resistance in small rolling bearings used in various motors such as fan motors.

[0003] In order to reduce the rotational resistance of a rolling bearing, it is effective to reduce the amount of grease that contacts both parts that rotate relative to each other. Therefore, by applying grease to the end of the fixed ring (in most cases, the outer ring) of the rolling bearing in the axial direction or to a sealing member arranged on the side of the end, it is possible to reduce the amount of grease that contacts the rolling element (ball) and the retainer that holds the rolling element (for example, refer to Patent Document 1). In the rolling bearing described in Patent Document 1, the grease is attached to the inner circumference of the outer ring that avoids the raceway surface that contacts the rolling element, and is sealed in an annular shape so as to be biased toward the inner circumference of the outer ring without contacting the outer circumference of the inner ring.

[0004] Furthermore, there is a rolling bearing in which a recess is provided on the circumferential surface of a raceway ring and grease is placed in the recess so that the grease is difficult to contact the rolling element (for example, refer to Patent Document 2). Patent Document 2 discloses a rolling bearing in which an outer ring has recesses formed on both sides of the raceway surface in the axial direction and a ridge formed between the recess and the raceway surface, and the recess has: a loading surface on which the grease is placed; and an inclined portion formed between the loading surface and the ridge and close to the outer circumferential surface of the outer ring toward the outside in the axial direction. Prior Art Literature Patent Literature

[0005] Patent document 1: Japanese Patent Application Publication No. 2017-150615. Patent document 2: Japanese Patent No. 7209902. Summary of the invention Problems to be solved by the invention

[0006] However, if the amount of grease is reduced in order to reduce the rotational resistance, there is a possibility that the life of the rolling bearing will be reduced due to the depletion of the grease. In addition, if the grease is placed on the loading surface on the opposite side of the ridge portion with the inclined portion in the recess clamped as in the structure disclosed in Patent Document 2, the base oil that seeps out of the grease must pass over the ridge portion after following the inclined portion before reaching the raceway surface, and there is a possibility that the base oil of the grease is insufficiently supplied to the rolling element. In particular, as the base oil seeps out of the grease, the ratio of the thickener in the grease increases, and therefore, if the rolling bearing is operated for a long time, the base oil supply capacity may gradually decrease. Therefore, in the conventional rolling bearings, there is the problem of balancing the assurance of durability and the reduction of rotational resistance.

[0007] Therefore, the present invention provides a rolling bearing, a rotating device, and a method for manufacturing a rolling bearing, which can achieve both ensuring durability and reducing rotation resistance. Solutions to Solve Problems

[0008] The rolling bearing involved in the first embodiment of the present invention comprises: an inner ring and an outer ring, which are arranged coaxially with each other; a rolling element, which is arranged between the inner ring and the outer ring; a sealing component, which is assembled 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; and grease, which is arranged between the rolling element and the sealing component, and one of the inner ring and the outer ring has a circumferential surface opposite to the other raceway, and on the circumferential surface, there are formed: a raceway surface, which supports the rolling element in a rolling manner; and a recess, which is provided at a portion extending along the axial direction from the end edge of the raceway surface in the axial direction, and is recessed in the radial direction, the grease is in contact with the recess, and the unmixed consistency of the grease is greater than 178 and less than 287.

[0009] According to the first scheme, the displacement of the grease in the axial direction can be restricted by the recess. Thus, the displacement of the grease can be suppressed and the grease can be in contact with the rolling element or the like by a desired amount or more. Therefore, the rotational resistance of the rolling bearing can be reduced. Furthermore, the grease can be arranged inside the recess, so that the total amount of the grease can be increased compared to a structure without a recess. Furthermore, the part of the grease that is not in contact with the rolling elements and the retainer is relatively soft and is in a state where oil easily leaks out to the outside. Therefore, even if the base oil in the part of the grease that is in contact with the rolling elements or the retainer is about to be insufficient, the base oil seeps out from the inside of the grease that is not in contact with the rolling elements and the retainer to the outside, and the base oil can continue to be supplied to the sliding part. In addition, even if the grease is applied in a manner that does not contact the rolling elements and the retainer, the base oil can be supplied from the surface of the grease to the sliding part, and the base oil also seeps out from the inside of the grease to the surface of the grease, and the base oil can be supplied to the sliding part. Therefore, even if the grease is arranged at a position away from the rolling elements and the retainer in order to reduce the rotational resistance of the rolling bearing, the base oil can be supplied to the sliding part for a long time, which can improve the durability of the rolling bearing. In addition, by making the unmixed consistency less than 287, it is possible to suppress excessive deformation caused by drooping or rotation of the grease due to gravity, and the shape of the portion of the grease that does not contact the rolling element and the retainer can be maintained at the initial shape. This can prevent the shape of the grease from being different for each rolling bearing and causing deviations in the rotational resistance. As described above, it is possible to provide a rolling bearing that can achieve both ensuring durability and reducing rotation resistance.

[0010] A rolling bearing according to a second aspect of the present invention may be the rolling bearing according to the first aspect, wherein the grease contacts a portion of the recessed portion that is inclined toward the outside in the axial direction relative to the radial direction.

[0011] According to the second embodiment, the portion of the recessed portion that is inclined toward the outside in the axial direction relative to the radial direction restricts the grease from being displaced toward the inside in the axial direction from the initial state. As a result, during repeated use of the rolling bearing, the grease is unlikely to be displaced toward the inside in the axial direction from the initial position, thereby increasing the amount of grease enclosed, and more reliably achieving the above-mentioned effects.

[0012] A rolling bearing according to a third aspect of the present invention may be the rolling bearing according to the first or second aspect, wherein the recess has a portion that faces in a direction inclined inward in the axial direction relative to the radial direction.

[0013] According to the third embodiment, the portion of the recessed portion that is inclined inwardly in the axial direction relative to the radial direction restricts the grease from being displaced outwardly in the axial direction, thereby preventing the grease or its base oil from flowing out toward the sealing component and leaking out from the gap between the sealing component and one raceway ring.

[0014] A rolling bearing according to a fourth aspect of the present invention may be the rolling bearing according to any one of the first to third aspects, wherein the grease is in contact with the sealing member.

[0015] According to the fourth scheme, when the sealing member is assembled while grease is applied to one raceway ring, even if the grease in contact with the sealing member is pushed inward in the axial direction by the sealing member, the grease can be prevented from contacting the rolling element or the like by more than a desired amount because the grease is restricted from moving inward in the axial direction by the recessed portion. Therefore, the rotational resistance of the rolling bearing can be reduced.

[0016] The rolling bearing according to a fifth aspect of the present invention may be the rolling bearing according to any one of the first to fourth aspects, wherein the grease contacts a ridge portion of an end edge on the raceway surface side formed in the recess.

[0017] According to the fifth aspect, the base oil seeping out of the grease does not need to go over the ridges when reaching the raceway surface, so that insufficient supply of the base oil of the grease to the rolling elements can be suppressed.

[0018] The rolling bearing involved in the 6th scheme of the present invention may also be a rolling bearing involved in any one of the above-mentioned 1st scheme to 5th scheme, wherein the aforementioned one raceway ring has a protrusion protruding toward the side of the aforementioned other raceway ring and forming the aforementioned peripheral surface, the aforementioned protrusion has an end surface facing the outside in the aforementioned axial direction and connected to the aforementioned peripheral surface at the peripheral edge on the side of the aforementioned other raceway ring, the aforementioned peripheral surface has a connecting surface formed between the aforementioned recess and the aforementioned end surface, and the aforementioned connecting surface is farther away from the aforementioned other raceway ring in the aforementioned radial direction than the end edge of the aforementioned raceway surface in the aforementioned axial direction.

[0019] According to the sixth scheme, when the tip of the nozzle is inserted from the outside of the rolling bearing to the inside of the outer ring and the inner ring in order to apply the grease to a predetermined position by ejecting the grease from the nozzle, it is possible to make it difficult for the connecting surface to contact the nozzle. Therefore, when applying the grease, it is easy to bring the nozzle close to the recessed portion, and thus it is possible to seek to improve the productivity of a rolling bearing with a small diameter. In addition, it is easy to bring the nozzle close to the recessed portion, so that the grease can be applied with good accuracy, and it is possible to prevent the grease from contacting the rolling element or the like more than the desired amount. Therefore, it is possible to seek to reduce the rotational resistance of the rolling bearing.

[0020] The rolling bearing involved in the 7th scheme of the present invention may also be a rolling bearing involved in any one of the above-mentioned 1st to 6th schemes, wherein the aforementioned peripheral surface has an inclined portion extending toward the aforementioned rolling surface side from the end edge of the aforementioned recessed portion at an inclination relative to the aforementioned radial direction and the aforementioned axial direction.

[0021] According to the seventh embodiment, even if the end of the concave portion on the raceway surface side extends in the radial direction, the peripheral surface gradually inclines from the concave portion toward the raceway surface, thereby enabling the base oil seeping out of the grease to flow from the concave portion along the inclined portion toward the raceway surface. Therefore, even if the grease is not arranged close to the raceway surface, insufficient supply of the base oil of the grease to the rolling element can be suppressed.

[0022] The rolling bearing according to an eighth aspect of the present invention may be the rolling bearing according to the seventh aspect, wherein the grease is arranged so as not to protrude from the inside of the recess toward the inclined portion in the radial direction.

[0023] According to the eighth aspect, the contact between the grease and the rolling elements can be suppressed. On the other hand, since the amount of grease applied is reduced, the effect of suppressing the insufficient supply of the grease base oil to the rolling elements as described above can be preferably obtained.

[0024] The rolling bearing according to a ninth aspect of the present invention may be the rolling bearing according to any one of the first to eighth aspects, wherein the difference between the mixed consistency and the unmixed consistency of the grease is less than 50.

[0025] According to the ninth aspect, the softness of the portion of the grease that is not in contact with the rolling elements and the retainer is close to the softness of the portion of the grease that is in contact with the rolling elements and the retainer. As a result, the difference in the leakage of the base oil between the portion of the grease that is in contact with the rolling elements or the retainer and the portion that is not in contact with the rolling elements and the retainer is reduced. Therefore, the rotational resistance of the rolling bearing can be stabilized over a long period of time.

[0026] The rolling bearing according to the tenth aspect of the present invention may be the rolling bearing according to any one of the first to ninth aspects, wherein the ratio of the difference between the mixed consistency and the unmixed consistency of the grease to the mixed consistency is less than 22.7%.

[0027] According to the tenth aspect, the softness of the portion of the grease that is not in contact with the rolling elements and the retainer is close to the softness of the portion of the grease that is in contact with the rolling elements or the retainer. As a result, the difference in the leakage of the base oil between the portion of the grease that is in contact with the rolling elements or the retainer and the portion that is not in contact with the rolling elements and the retainer is reduced. Therefore, the rotational resistance of the rolling bearing can be stabilized over a long period of time.

[0028] The rolling bearing according to the eleventh aspect of the present invention may be the rolling bearing according to any one of the first to tenth aspects, wherein the unmixed consistency of the grease after being left at 85° C. for 18 hours is greater than 158.

[0029] According to the eleventh aspect, the degree of hardening of the grease can be set to such an extent that even if the grease is exposed to high temperatures or left for a long time, the base oil can smoothly ooze out, thereby providing a rolling bearing with high durability.

[0030] The rotating device involved in the 12th embodiment of the present invention comprises: a rotating body, which is configured in a rotatable manner; a support body, which supports the aforementioned rotating body in a rotatable manner; and a rolling bearing involved in any one of the above-mentioned embodiments 1 to 11, which is interposed between the aforementioned rotating body and the aforementioned support body.

[0031] According to the twelfth aspect, a rolling bearing that achieves both durability and reduced rotational resistance is provided, thereby achieving a longer life of the rotating device and power saving of the rotating device due to reduced rotational resistance of the rotating body to the supporting body.

[0032] The manufacturing method of a rolling bearing involved in the 13th scheme of the present invention is the following rolling bearing manufacturing method: it comprises: an inner ring and an outer ring, which are arranged coaxially with each other; a rolling element, which is arranged between the aforementioned inner ring and the aforementioned outer ring; a sealing component, which is assembled on the aforementioned inner ring or the aforementioned outer ring, covering the space between the aforementioned inner ring and the aforementioned outer ring from the outside in the axial direction; and grease, which is arranged between the aforementioned rolling element and the aforementioned sealing component, and one of the aforementioned inner ring and the aforementioned outer ring has a circumferential surface opposite to the other raceway ring, and on the aforementioned circumferential surface, there are formed: a raceway surface, which supports the aforementioned rolling element in a manner capable of rolling; and a recess, which is provided at a portion extending from the axial end edge of the aforementioned raceway surface along the aforementioned axial direction and is recessed in the radial direction. The manufacturing method of the rolling bearing comprises a coating step of applying the aforementioned grease by bringing it into contact with the aforementioned recess, so that the unmixed consistency of the aforementioned grease is greater than 178 and less than 287.

[0033] According to the 13th scheme, grease can be applied to one raceway ring in a manner that limits displacement in the axial direction through a recess. As a result, displacement of the grease can be suppressed and the grease can be contacted with the rolling element or the like in an amount greater than the desired amount. Therefore, the rotational resistance of the rolling bearing can be reduced. Furthermore, the grease can be arranged on the inner side of the recess, so that the total amount of grease can be increased compared to the case where the grease is not applied to the recess. Furthermore, the unmixed consistency of the grease is relatively small, so when the grease is pushed inward in the axial direction by the sealing component, the grease can also be easily deformed in the radial direction. As a result, the movement of the grease inward in the axial direction can be suppressed, and the grease can be suppressed from contacting the rolling element or the retainer beyond the necessary amount. Through the above, a rolling bearing that can take into account both ensuring durability and reducing rotational resistance can be manufactured.

[0034] The manufacturing method of a rolling bearing involved in the 14th scheme of the present invention is that in the manufacturing method of a rolling bearing involved in the above-mentioned 13th scheme, the aforementioned sealing component has: an annular seat portion, which contacts with the aforementioned one raceway ring from the outside in the aforementioned axial direction; an extension portion, which extends from the peripheral edge of the other raceway ring side of the aforementioned inner ring and the aforementioned outer ring of the aforementioned seat portion to the outside in the aforementioned axial direction; and a flat portion, which extends from the end edge of the outer side in the aforementioned axial direction of the aforementioned extension portion toward the aforementioned other raceway ring in the radial direction, and in the aforementioned coating step, the aforementioned grease is applied from the aforementioned one raceway ring to the aforementioned one raceway ring. The contact portion of the raceway ring is coated in a manner that protrudes toward the outside in the aforementioned axial direction and toward the side of the aforementioned other raceway ring. The manufacturing method of the rolling bearing also comprises: a contact process, which causes the aforementioned sealing component to approach the aforementioned one raceway ring from the outside in the aforementioned axial direction, so that the aforementioned flat portion contacts the end edge of the aforementioned grease on the outside in the aforementioned axial direction; and an assembly process, which, after the aforementioned contact process, causes the aforementioned sealing component to approach the aforementioned one raceway ring, causes the aforementioned seat portion to contact the aforementioned one raceway ring from the outside in the aforementioned axial direction, and uses the aforementioned flat portion to push the aforementioned grease toward the inside in the aforementioned axial direction.

[0035] According to the 14th scheme, in the contact process, the flat surface of the sealing member contacts the outer edge of the grease in the axial direction, so that in the assembly process, in the process of pushing the flat surface inward in the axial direction, it is possible to provide room for the grease to expand in the radial direction toward the extension and the seat of the sealing member. Therefore, it is possible to suppress the grease from expanding significantly toward the other raceway ring side and the rolling element side. Therefore, it is possible to easily suppress the grease from directly contacting the rolling element and the other raceway ring. Furthermore, since the extension portion is provided between the plane portion and the seat portion, it is difficult to push the grease toward the rolling element side compared to a configuration in which the plane portion extends from the seat portion toward the other raceway ring side. Therefore, the grease can be pre-arranged at a position closer to the rolling element, thereby increasing the amount of grease. Effects of the Invention

[0036] 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 ensuring durability and reducing rotation resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a plan view of the rolling bearing according to the first embodiment. Figure 2 yes Figure 1 Longitudinal section view on line II-II. Figure 3 It is a longitudinal cross-sectional view of a rolling bearing for explaining the grease application method according to the first embodiment. Figure 4It is a longitudinal cross-sectional view of a rolling bearing for explaining the grease application method according to the first embodiment. Figure 5 It is a longitudinal sectional view of a rolling bearing according to a first modified example of the first embodiment. Figure 6 It is a longitudinal sectional view of a rolling bearing according to a second modified example of the first embodiment. Figure 7 It is a longitudinal sectional view of a rolling bearing according to a third modified example of the first embodiment. Figure 8 It is a longitudinal sectional view of a rolling bearing according to a fourth modified example of the first embodiment. Fig. 9 It is a longitudinal sectional view of a rolling bearing according to a second embodiment. Fig.10 It is a longitudinal sectional view of a rolling bearing according to a third embodiment. Fig.11 It is a longitudinal sectional view of a rolling bearing according to a fifth embodiment. Fig.12 It is a longitudinal sectional view of a rolling bearing according to a modified example of the fifth embodiment. Fig.13 It is a longitudinal sectional view of a rolling bearing according to a sixth embodiment. Fig.14 It is a longitudinal sectional view of a rolling bearing according to a first modified example of the sixth embodiment. Fig.15 It is a longitudinal sectional view of a rolling bearing according to a second modified example of the sixth embodiment. Fig.16 It is a longitudinal sectional view of a rolling bearing according to a seventh embodiment. Fig.17 It is a longitudinal sectional view of a rolling bearing according to a first modified example of the seventh embodiment. Fig.18 It is a longitudinal sectional view of a rolling bearing according to a second modified example of the seventh embodiment. Fig.19 It is a longitudinal sectional view of a rolling bearing according to an eighth embodiment. Fig. 20 It is a longitudinal sectional view of a rolling bearing according to a ninth embodiment. Fig.21 It is a longitudinal sectional view of a rolling bearing according to a first modified example of the ninth embodiment. Fig. 22 It is a longitudinal sectional view of a rolling bearing according to a second modified example of the ninth embodiment. DETAILED DESCRIPTION

[0038] Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. In the following description, components having the same or similar functions are denoted by the same reference numerals, and repeated descriptions of these components may be omitted.

[0039] [First embodiment] Reference Figure 1 and Figure 2 Next, a first embodiment of the present invention will be described. Figure 1 It is a plan view of the rolling bearing according to the first embodiment. Figure 2 yes Figure 1 A longitudinal section view of the II-II line. Figure 2 In FIG. 1 , a rotating device 2 equipped with a rolling bearing 1 is shown by imaginary lines.

[0040] like Figure 1 and Figure 2 As shown, the rolling bearing 1 is a radial ball bearing having an inner ring 10 and an outer ring 20 as raceways, a plurality of rolling elements 30, a retainer 40, and a pair of sealing members 50. The rolling bearing 1 is provided in a rotating device 2 such as a fan motor. The rotating device 2 includes: a shaft 3 (rotating body) formed so as to be rotatable about a common axis O; and a frame 4 (support body) fixedly provided to rotatably support the shaft 3. The rolling bearing 1 is interposed between the shaft 3 and the frame 4.

[0041] The inner ring 10 and the outer ring 20 are coaxially arranged with each other so that their central axes coincide with the common axis O. In the present embodiment, the direction in which the common axis O extends is referred to as the axial direction, the direction extending radially from the common axis O, which is orthogonal to the common axis O, is referred to as the radial direction, and the direction revolving around the common axis O is referred to as the circumferential direction. In addition, one of the directions parallel to the axial direction and pointing in opposite directions is defined as the upper direction, and the other is defined as the lower direction.

[0042] The inner ring 10 is provided as a rotating ring. The inner ring 10 is externally inserted into the shaft 3 and fixed to the shaft 3. The outer ring 20 is provided as a fixed ring. The outer ring 20 is inserted into the recess (or through hole) of the frame 4 and fixed to the frame 4. The outer ring 20 surrounds the inner ring 10 from the outside in the radial direction while providing an annular space between the inner ring 10 and the outer ring 10. A plurality of rolling elements 30 are arranged between the inner ring 10 and the outer ring 20 and are held by the retainer 40 in a rollable manner. The retainer 40 holds each rolling element 30 in a rotatable manner while arranging the plurality of rolling elements 30 evenly 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 outside in the axial direction.

[0043] The outer ring 20 is formed in an annular shape by a metal material such as stainless steel or bearing steel. However, the outer ring 20 is not limited to being made of metal, and may be formed of other materials. The outer ring 20 includes: an outer ring body 21 whose width in the axial direction is equal to the width of the inner ring 10 in the axial direction; and a protrusion 22 that protrudes from the outer ring body 21 toward the inner side in the radial direction and extends throughout the entire circumferential direction. The protrusion 22 is formed in the central portion of the outer ring body 21 in the axial direction. The width of the protrusion 22 in the axial direction is shorter than the width of the outer ring body 21 in the axial direction, and is larger than the outer diameter of the rolling element 30.

[0044] The protrusion 22 has a pair of end faces 22a facing outward in the axial direction and an inner peripheral surface 22b (peripheral surface) connecting the inner peripheral edges of the pair of end faces 22a to each other. Each end face 22a extends in parallel in both the radial direction and the circumferential direction. On the inner peripheral surface 22b, an outer ring raceway surface 23 is formed that is recessed outward in the radial direction. The outer ring raceway surface 23 is formed in a hemispherical shape in a cross-sectional view along the outer surface of the rolling element 30, and is formed in an annular shape that extends in the circumferential direction over the entire circumference of the inner peripheral surface 22b. The outer ring raceway surface 23 is formed in a portion of the inner peripheral surface 22b that is located in the center of the axial direction.

[0045] Furthermore, a recessed portion 24 is formed on the inner peripheral surface 22b, which is recessed toward the outside in the radial direction. The recessed portion 24 is provided in a portion of the inner peripheral surface 22b extending in the axial direction from the end edge of the outer ring raceway surface 23 in the axial direction. The recessed portion 24 is provided above the outer ring raceway surface 23. The recessed portion 24 is provided at intervals in the axial direction relative to the outer ring raceway surface 23. The recessed portion 24 is provided at intervals in the axial direction relative to the end surface 22a facing upward. The recessed portion 24 extends continuously throughout the entire circumferential direction. The recessed portion 24 extends in an arc shape on the longitudinal section of the rolling bearing 1. For example, on the longitudinal section of the rolling bearing 1, the curvature radius of the recessed portion 24 may be consistent with the curvature radius of the outer ring raceway surface 23, or may be different from the curvature radius of the outer ring raceway surface 23. In addition, the recessed portion 24 may not extend with a constant curvature on the longitudinal section of the rolling bearing 1. The recess 24 has an outer surface 24a which faces a direction inclined toward the outer side in the axial direction relative to the radial direction (inward and upward in the radial direction, or upward); and an inner surface 24b which faces a direction inclined toward the inner side in the axial direction relative to the radial direction (inward and downward in the radial direction, or downward). The portion of the inner peripheral surface 22b other than the outer ring raceway surface 23 and the recess 24 extends in the axial direction with a certain inner diameter.

[0046] The inner peripheral surface 22b includes a ridge 25 formed at the end edge on the outer ring raceway surface 23 side (axially inner side) of the recess 24. In the longitudinal section of the rolling bearing 1, the ridge 25 may be rounded or sharp.

[0047] The outer ring body 21 has a pair of inner peripheral surfaces 21a extending from the outer peripheral edges of the end surfaces 22a of the protrusions 22 to the opening edge of the outer ring 20. The axially inner portion of each inner peripheral surface 21a is located radially outward of the axially outer portion.

[0048] The inner ring 10 is formed in an annular shape from a metal material such as stainless steel or bearing steel. However, the inner ring 10 is not limited to being made of metal, and may be formed from other materials. An inner ring raceway surface 11 that is recessed inward in the radial direction is formed on the outer circumferential surface of the inner ring 10. The inner ring raceway surface 11 is formed in a hemispherical shape in a cross-sectional view along the outer surface of the rolling element 30, and is formed in an annular shape that extends in the circumferential direction over the entire circumference of the outer circumferential surface. The inner ring raceway surface 11 is formed in a portion of the outer circumferential surface of the inner ring 10 that is located in the center in the axial direction, and is arranged to face the outer ring raceway surface 23 in the radial direction. The portion of the outer circumferential surface of the inner ring 10 other than the inner ring raceway surface 11 extends in the axial direction with a certain outer diameter.

[0049] like Figure 2 As shown, the plurality of rolling elements 30 are formed in a spherical shape from a metal material such as stainless steel or bearing steel. The plurality of rolling elements 30 are arranged between the outer ring raceway surface 23 and the inner ring raceway surface 11, and are supported in a rolling manner by the outer ring raceway surface 23 and the inner ring raceway surface 11. The plurality of rolling elements 30 are maintained at intervals in the circumferential direction by a retainer 40.

[0050] The retainer 40 is formed of a synthetic resin or a metal material in an annular shape as a whole. The retainer 40 is arranged with the common axis O as the center. The retainer 40 includes: an annular portion 41, which is formed in an annular shape and is arranged below the plurality of rolling elements 30; and a plurality of columnar portions 42, which are protruded upward from the annular portion 41 and are arranged at intervals in the circumferential direction. The columnar portions 42 are arranged evenly in the circumferential direction. A pair of columnar portions 42 adjacent in the circumferential direction form a ball hole between each other. The ball hole penetrates the retainer 40 in the radial direction and opens upward at the upper end surface of the retainer 40. The ball holes are arranged corresponding to the number of rolling elements 30, and each rolling element 30 is held in a rollable manner. Thus, the retainer 40 arranges the rolling elements 30 evenly in the circumferential direction at intervals. The retainer 40 is arranged with a gap relative to 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 the present embodiment, the entire retainer 40 is located further inward in the axial direction than the pair of end surfaces 22 a of the protruding portion 22 of the outer ring 20 .

[0051] like Figure 1 and Figure 2As shown, the sealing member 50 is formed in the shape of a circular ring. The sealing member 50 is arranged with the common axis O as the center. The sealing member 50 is formed uniformly throughout the entire circumference. The sealing member 50 is embedded in the outer ring 20 from the outside in the axial direction. One sealing member 50 is arranged on each side in the axial direction relative to the plurality of rolling elements 30. The sealing member 50 has: an annular seat portion 51, which contacts the outer ring 20 from the outside in the axial direction; an extension portion 52, which extends from the inner peripheral edge of the seat portion 51 to the outside in the axial direction; a flat portion 53, which extends from the end edge of the outer side in the axial direction of the extension portion 52 toward the inner ring 10 in the radial direction; and a stopper portion 54, which extends from the outer peripheral edge of the seat portion 51 to the outside in the radial direction and the outside in the axial direction.

[0052] like Figure 2 As shown, the seat portion 51 overlaps with the end face 22a of the protrusion 22 of the outer ring 20 from the outside in the axial direction. The seat portion 51 extends substantially parallel to the end face 22a of the protrusion 22 of the outer ring 20. The seat portion 51 protrudes radially inwardly from the end face 22a of the protrusion 22 in a plan view from the axial direction. The distance by which the seat portion 51 protrudes radially inwardly from the end face 22a of the protrusion 22 is less than 10% of the radial distance between the inner ring 10 and the outer ring 20, and preferably less than 5%. The protrusion 52 extends from the inner peripheral edge of the seat portion 51 to the outside in the axial direction and to the inside in the radial direction. The flat portion 53 overlaps with the center of the rolling element 30 in a plan view. The inner peripheral edge of the flat portion 53 is arranged with a gap between it and the outer peripheral surface of the inner ring 10. The surface of the flat portion 53 facing the inside in the axial direction is a flat surface extending in the circumferential direction and the radial direction. The outer peripheral edge of the locking portion 54 is locked to the inner peripheral surface 21a of the outer ring body 21 from the inner side in the axial direction. Thus, 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.

[0053] Grease 60 is sealed in the rolling bearing 1. Grease 60 is arranged between the rolling element 30 and the sealing member 50. Grease 60 is arranged on the same side as the recess 24 relative to the rolling element 30 in the annular space between the inner ring 10 and the outer ring 20 in the axial direction. In the present embodiment, grease 60 is arranged on the opposite side of the annular portion 41 of the retainer 40 with the rolling element 30 sandwiched therebetween in the axial direction. Grease 60 is arranged above the rolling element 30. Grease 60 is arranged along the circumferential direction. Grease 60 extends in a circular ring or arc shape and is arranged coaxially with the common axis O.

[0054] The grease 60 includes an outer ring contact portion 61 that contacts the inner peripheral surface 22b of the protrusion 22 of the outer ring 20, and a seal member contact portion 62 that contacts the flat surface 53 of the seal member 50 on the outer side in the axial direction and on the inner side in the radial direction of the outer ring contact portion 61. The outer ring contact portion 61 and the seal member contact portion 62 extend in the circumferential direction over the entire length of the grease 60. The outer ring contact portion 61 has a width in the axial direction over the entire circumferential direction. The outer ring contact portion 61 contacts the recess 24 on the inner peripheral surface 22b of the protrusion 22. The outer ring contact portion 61 contacts the recess 24 over the entire circumference. The outer ring contact portion 61 contacts the outer 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 25. In the present embodiment, the outer ring contact portion 61 contacts the ridge 25 over the entire circumference. Furthermore, the outer ring contact portion 61 contacts the inward surface 24b of the recess 24 and the portion of the recess 24 facing the inner side in the radial direction. In the present embodiment, the outer ring contact portion 61 contacts the entire recess 24. It is ideal that the grease 60 does not contact any portion other than the recess 24 with respect to the outer ring 20. That is, the outer ring contact portion 61 is provided at a distance in the axial direction relative to the contact portion between the outer ring 20 and the seat portion 51 of the sealing member 50. The sealing member contact portion 62 has a width in the radial direction over the entire circumferential direction. The sealing member contact portion 62 contacts the flat surface portion 53 at a portion at a distance in the radial direction from the connection portion between the extension portion 52 and the flat surface portion 53 of the sealing member 50.

[0055] The grease 60 extends outward in the axial direction and inward in the radial direction from the outer ring contact portion 61 toward the seal member contact portion 62. The grease 60 includes an inner surface 63 and an outer surface 64. The inner surface 63 connects the inner edge of the outer ring contact portion 61 in the axial direction with the inner edge of the seal member contact portion 62 in the radial direction. The inner surface 63 faces the outer peripheral surface of the inner ring 10 and the rolling element 30. The upper half of the inner surface 63 extends from the inner edge of the seal member contact portion 62 in the radial direction to the inner side of the axial direction and the inner side of the radial direction. The lower half of the inner surface 63 extends from the inner edge of the outer ring contact portion 61 in the axial direction to the outer side of the axial direction and the inner side of the radial direction, and is connected to the lower edge of the upper half. The boundary between the upper half and the lower half of the inner surface 63 forms the inner peripheral edge of the grease 60 located most inward in the radial direction. The inner surface 63 is separated from the inner ring 10, the rolling element 30, and the retainer 40. As a result, the grease 60 does not contact the inner ring 10, the rolling element 30, and the retainer 40.

[0056] The outer surface 64 connects the outer edge of the outer ring contact portion 61 in the axial direction to the outer edge of the seal member contact portion 62 in the radial direction. The outer surface 64 faces the inner peripheral surface 22b of the protrusion 22 of the outer ring 20 and the seal member 50. The outer surface 64 extends from the outer edge of the seal member contact portion 62 in the radial direction to the inner side and the outer side in the radial direction, and is connected to the outer edge of the outer ring contact portion 61 in the axial direction. The outer surface 64 is separated from the seat portion 51 and the extension portion 52 of the seal member 50. As a result, the grease 60 does not contact the seat portion 51 and the extension portion 52 of the seal member 50, which are located closer to the outer ring 20 than the flat portion 53.

[0057] The grease 60 is formed in such a manner that the cross-sectional area of ​​the cross section along the vertical plane of the common axis O gradually increases from the end portion on the outside in the axial direction toward the inside in the axial direction. In the present embodiment, the grease 60 is formed in such a manner that the cross-sectional area of ​​the cross section along the vertical plane of the common axis O gradually increases from the end portion on the outside in the axial direction toward the inside in the axial direction in the portion corresponding to the upper half of the inner surface 63.

[0058] The grease 60 may contact at least one of the rolling element 30 and the retainer 40. For example, the grease 60 may contact at least one of the rolling element 30 and the retainer 40 by changing over time from an initial state in which the rolling element 30 and the retainer 40 are not in contact.

[0059] The structure of the grease 60 will be described. In addition, the grease 60 may include other components in addition to the base oil and the thickener as needed.

[0060] The base oil is not particularly limited, but mineral oil or synthetic oil can be cited. As the mineral oil, well-known mineral oils used as base oils can be used, for example, naphthenic mineral oils, paraffinic mineral oils, hydrogenated mineral oils, solvent refined mineral oils, highly refined mineral oils, etc. can be cited. Mineral oils can be used alone or in combination of two or more. For example, multiple types of mineral oils can be mixed to adjust to the target properties.

[0061] As the synthetic oil, well-known synthetic oils used as base oils can be used, for example, aliphatic hydrocarbon oils such as polyalphaolefin (PAO) or polybutene, aromatic hydrocarbon oils such as alkylbenzene and alkylnaphthalene, ester oils such as polyol esters and phosphate esters, ether oils such as polyphenylene ether, polyalkylene glycol oils, silicone oils, fluorine oils, etc. can be listed. These synthetic oils can also be used alone or in combination of two or more. For example, multiple types of synthetic oils can also be mixed to adjust to the target properties.

[0062] The thickener plays a role in maintaining the grease 60 in a semi-solid state. As the thickener, well-known thickeners commonly used in rolling bearing grease can be used without limitation. As the thickener, for example, urea compounds or lithium soaps, calcium soaps, complex lithium soaps, complex calcium soaps, silica gel, polytetrafluoroethylene, organic bentonite, etc. can be cited. As the thickener, urea compounds are preferred from the viewpoint of excellent heat resistance. The thickener can also be used alone or in combination of two or more. For example, multiple types of thickeners can also be mixed to adjust to the target properties.

[0063] The unmixed consistency of the grease 60 of the present embodiment is greater than 178 and less than 287. The difference between the mixed consistency and the unmixed consistency of the grease 60 is preferably less than 50. The ratio of the difference between the mixed consistency and the unmixed consistency of the grease 60 to the mixed consistency is preferably less than 22.7%. The unmixed consistency of the grease 60 after being left at 85°C for 18 hours is preferably greater than 158. In the following description, leaving at 85°C for 18 hours is referred to as high-temperature leaving.

[0064] Next, a method for manufacturing the rolling bearing 1 according to the present embodiment will be described. The method for manufacturing the rolling bearing 1 according to the present embodiment includes a coating step and a sealing step.

[0065] Figure 3 and Figure 4 It is a longitudinal cross-sectional view of a rolling bearing for explaining the grease application method according to the first embodiment. like Figure 3 As shown in FIG. 1 , the coating process is performed in a state where the sealing member 50 is not mounted on the outer ring 20. That is, the grease 60 is applied in a state where the annular space between the inner ring 10 and the outer ring 20 is open in the axial direction and the rolling elements 30 and the retainer 40 are exposed. In the coating process, the nozzle A is rotated relative to the outer ring 20 about the common axis O, and the grease 60 is discharged from the nozzle A. At this time, the direction of the nozzle A is adjusted so that the grease 60 is discharged from the nozzle A to the outside in the radial direction and the inside in the axial direction. Furthermore, the position of the nozzle A is adjusted so that the discharged grease 60 contacts the recessed portion 24 of the inner peripheral surface 22b of the protrusion 22 of the outer ring 20, and the grease 60 does not contact the rolling elements 30 and the retainer 40. The grease 60 applied to the outer ring 20 is spread in a circumferential shape or an arc shape while the nozzle A is rotated relative to the outer ring 20 and the grease 60 is discharged. The grease 60 is applied so as to protrude from the contact portion with the outer ring 20 toward the axial outer side and the radial inner side in the discharge direction from the nozzle A. The axial outer side end surface of the applied grease 60 is formed in a convex shape that bulges toward the axial outer side.

[0066] Next, the sealing process is performed. Figure 4As shown in FIG. 1 , in the sealing step, the sealing member 50 is brought close to the outer ring 20 from the outside in the axial direction, and the sealing member 50 is assembled to the outer ring 20. In the process of displacing the sealing member 50 inward in the axial direction, before the seat portion 51 contacts the end face 22a of the protruding portion 22 of the outer ring 20, the flat surface portion 53 of the sealing member 50 is first brought into contact with the outer edge of the grease 60 in the axial direction (contact step). At this time, the grease 60 contacts the radial middle portion of the flat surface portion 53. The radial middle portion only needs to be located radially inward from the outer peripheral edge of the flat surface portion 53 and radially outward from the inner peripheral edge. Thereafter, the sealing member 50 is brought closer to the outer ring 20, and the seat portion 51 contacts the end face 22a of the protruding portion 22 of the outer ring 20 from the outside in the axial direction (assembly step). At this time, the grease 60 is pressed inward in the axial direction by the flat surface portion 53 of the sealing member 50. As a result, the grease 60 is pressed by the flat surface portion 53 and spreads in the radial direction, thereby forming a seal member contact portion 62 of the grease 60 .

[0067] The rolling bearing 1 is formed by the above. In the coating process of the present embodiment, the nozzle A is rotated relative to the outer ring 20 while applying the grease 60, but the grease may be applied in a circumferential or arc shape by ejecting the grease from a nozzle having an ejection hole extending in the circumferential direction.

[0068] As described above, in the present embodiment, the rolling bearing 1 has the following structure. On the inner circumferential surface 22b of the protrusion 22 of the outer ring 20, there are formed: an outer ring raceway surface 23 that supports the rolling element 30 in a rolling manner; and a recessed portion 24 that is provided at a portion extending in the axial direction from the axial end edge of the outer ring raceway surface 23 and is recessed in the radial direction. The grease 60 is in contact with the recessed portion 24. According to this structure, the displacement of the grease 60 in the axial direction can be restricted by the recessed portion 24. Thus, the displacement of the grease 60 can be suppressed and the grease 60 can be in contact with the rolling element 30 or the retainer 40 by more than the desired amount. Therefore, the rotational resistance of the rolling bearing 1 can be reduced. Furthermore, the grease 60 can be arranged inside the recessed portion 24, so that the total amount of the grease 60 can be increased compared with the structure in which the recessed portion is not formed.

[0069] Here, the grease 60 is disposed between the rolling element 30 and the sealing member 50, and most (or all) of the grease 60 does not contact the rolling element 30 and the retainer 40. That is, the portion of the grease 60 that contacts the rolling element 30 or the retainer 40 and is sheared during the operation of the rolling bearing 1 is very small, and there are cases where the grease 60 does not contact the rolling element 30 and the retainer 40.

[0070] The hardness of grease is different between a state where it is not sheared (unmixed state) and a state where it is sheared (mixed state). Generally, grease becomes soft when it is sheared. Therefore, the portion of grease 60 that is in contact with the inner ring 10, rolling element 30, or retainer 40 becomes soft due to continuous shearing of the rolling element 30 or retainer 40, which promotes the seepage of the base oil. On the other hand, the portion of grease 60 that is not in contact with the rolling element 30 or retainer 40 remains in a hard state. In the case where the portion of grease 60 that is in contact with the rolling element 30 or retainer 40 is small, if the base oil seeping out of the portion that is sheared by the rolling element 30 or retainer 40 is insufficient, the base oil supply becomes insufficient because most of the grease 60 is not stirred and remains in a hard state, and the life of the rolling bearing 1 is reached. The same is true when the entire grease 60 is not in contact with the rolling element 30 or retainer 40.

[0071] However, there are mixed consistency and unmixed consistency as indicators showing properties related to the hardness of grease. Mixed consistency is an indicator of the hardness of grease just after being sheared. Therefore, the state of grease when measuring mixed consistency is close to the state of the part of rolling bearing or grease that is in contact with rolling elements or retainers and is sheared. On the other hand, unmixed consistency is an indicator of the hardness of grease in a state that is not sheared. Therefore, the state of grease when measuring unmixed consistency is close to the state of the part of rolling bearing or grease that is not in contact with rolling elements and retainers.

[0072] In the present embodiment, the unmixed viscosity of the grease 60 is greater than 178 and less than 287. According to this structure, the portion of the grease 60 that is not in contact with the rolling element 30 and the retainer 40 is relatively soft and is in a state where oil can easily flow out to the outside. Therefore, even if the base oil in the portion of the grease 60 that is in contact with the rolling element 30 or the retainer 40 is about to be insufficient, the base oil can seep out from the inside of the grease 60 that is not in contact with the rolling element 30 and the retainer 40 to the outside, and the base oil can continue to be supplied to the sliding part. In addition, even if the grease 60 is applied in a manner that does not contact the rolling element 30 and the retainer 40, the base oil can be supplied from the surface of the grease 60 to the sliding part, and the base oil can seep out from the inside of the grease 60 to the surface of the grease 60, and the base oil can be supplied to the sliding part. Therefore, even when the grease 60 is arranged at a position away from the rolling elements 30 and the cage 40 in order to reduce the rotation resistance of the rolling bearing 1, the base oil can be supplied to the sliding parts for a long period of time, and the durability of the rolling bearing 1 can be improved.

[0073] In addition, the unmixed consistency is less than 287, so that the grease 60 can be prevented from sagging due to gravity or excessive deformation due to rotation, and the shape of the portion of the grease 60 that is not in contact with the rolling element 30 and the retainer 40 can be maintained in the initial shape. This can prevent the shape of the grease 60 from being different for each rolling bearing 1 and the occurrence of deviations in the rotation resistance. As described above, it is possible to provide the rolling bearing 1 that can achieve both ensuring durability and reducing rotation resistance.

[0074] Furthermore, in the present embodiment, the grease 60 contacts both the inner peripheral surface of the outer ring 20 and the sealing member 50. In this configuration, when the grease 60 is sealed between the outer ring 20 and the inner ring 10, after the grease 60 is applied to the outer ring 20 and the sealing member 50 is assembled to the outer ring 20, the grease 60 is pressed inward in the axial direction by the sealing member 50. Here, as in the conventional case, when the grease with a relatively small unmixed consistency (hardness) is pressed inward in the axial direction by the sealing member, although it is accompanied by a slight deformation, the entire grease moves inward in the axial direction, and there is a possibility that the grease 60 contacts the rolling element 30 or the retainer 40 by a larger amount than desired. In the present embodiment, the grease 60 has a relatively large unmixed consistency (softness), so when the grease 60 is pressed inward in the axial direction by the sealing member 50, it is also easy to deform in the radial direction, and the grease 60 can be suppressed from moving inward in the axial direction, and the grease 60 can be suppressed from contacting the rolling element 30 or the retainer 40 more than desired. Therefore, it is possible to suppress an increase in the rotation resistance of the rolling bearing 1 .

[0075] The grease 60 contacts the outer surface 24a of the recess 24 which is inclined toward the outer side in the axial direction relative to the radial direction. According to this structure, the outer surface 24a of the recess 24 restricts the displacement of the grease 60 toward the inner side in the axial direction from the initial state. Therefore, during the repeated use of the rolling bearing 1, the grease 60 is unlikely to be displaced toward the inner side in the axial direction from the initial position, so that the amount of grease 60 sealed can be increased, and the above-mentioned effects can be obtained more reliably.

[0076] Furthermore, the grease 60 contacts the outer surface 24a of the recess 24, so that the shape and position of the grease 60 are unlikely to change due to vibration during transportation or long-term storage (especially storage in a high temperature environment). Therefore, it is possible to provide a rolling bearing 1 that suppresses changes in rotational resistance from the initial stage of manufacturing.

[0077] The recessed portion 24 has an inward surface 24b that is inclined inwardly in the axial direction relative to the radial direction. According to this configuration, the inward surface 24b of the recessed portion 24 restricts the grease 60 from being displaced outwardly in the axial direction. Thus, the grease 60 or its base oil can be prevented from flowing out to the sealing member 50 side and leaking out from the gap between the sealing member 50 and the outer ring 20.

[0078] In particular, in the present embodiment, the grease 60 contacts the outer surface 24a of the recess 24, and thus the grease 60 is supported by the seal member 50 in addition to the recess 24. Therefore, the shape and position of the grease 60 are unlikely to change due to vibration during transportation or long-term storage (particularly, storage in a high temperature environment), etc. Therefore, it is possible to provide a rolling bearing 1 that suppresses changes in rotation resistance from the initial stage of manufacturing.

[0079] Furthermore, the grease 60 contacts the extension portion 52 and the flat portion 53 of the sealing member 50, and thus the effect of suppressing the change in the shape and position of the grease 60 is easily exerted. In addition, the amount of the grease 60 can be increased, and thus higher durability can be imparted to the rolling bearing 1. In addition, the grease 60 contacts at least one of the extension portion 52 and the flat portion 53 of the sealing member 50, and thus the above-mentioned effect is exerted. However, it is more desirable that the grease 60 contacts the flat portion 53.

[0080] The grease 60 is in contact with the sealing member 50. According to this configuration, when the sealing member 50 is assembled to the outer ring 20 in a state where the grease 60 is 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, since the displacement of the grease 60 inward in the axial direction is restricted by the recess 24 as described above, it is possible to prevent the grease 60 from contacting the rolling element 30 or the retainer 40 by more than a desired amount. Therefore, the rotation resistance of the rolling bearing 1 can be reduced.

[0081] The grease 60 also contacts the ridge 25 formed at the end edge of the outer ring raceway 23 side in the recess 24. According to this structure, the base oil seeping from the grease 60 does not need to cross the ridge 25 when reaching the outer ring raceway 23, so that the base oil of the grease 60 can be prevented from being insufficiently supplied to the rolling element 30.

[0082] The grease 60 includes an outer ring contact portion 61 that contacts the inner peripheral surface 22b of the protruding portion 22 of the outer ring 20, and a seal member contact portion 62 that contacts the flat surface portion 53 of the seal member 50 on the outer side in the axial direction and on the inner side in the radial direction of the outer ring contact portion 61. The area of ​​the seal member contact portion 62 is larger than the contact area of ​​the grease 60 with the protruding portion 52 and the seat portion 51 of the seal member 50. According to this configuration, when the seal member 50 is assembled after the grease 60 is applied to a predetermined portion, the grease 60 pressed inward in the axial direction by the flat surface portion 53 of the seal member 50 can be provided with room to spread in the radial direction toward the protruding portion 52 and the seat portion 51. Therefore, it is possible to suppress the grease 60 from spreading significantly toward the inner ring 10 side and the rolling element 30 side. Therefore, it is possible to easily suppress the grease 60 from directly contacting the rolling element 30 and the retainer 40. Furthermore, since the seal member 50 has the extension portion 52 between the flat portion 53 and the seat portion 51, the grease 60 can be arranged at a position farther from the rolling element 30 than in a configuration where the flat portion extends radially inward from the seat portion. Therefore, the amount of grease 60 can be increased. As described above, it is possible to provide the rolling bearing 1 that can achieve both ensuring durability and reducing rotation resistance.

[0083] The grease 60 does not contact the extension 52. According to this configuration, when the seal member 50 is assembled, the grease 60 that is pushed inward in the axial direction by the flat surface portion 53 of the seal member 50 can be provided with a larger space to spread in the radial direction toward the extension 52. Therefore, it is possible to suppress the grease 60 from spreading greatly toward the inner ring 10 side and the rolling element 30 side. Therefore, it is possible to easily suppress the grease 60 from contacting the rolling element 30, the retainer 40, and the inner ring 10 more than necessary.

[0084] In addition, the difference between the mixed consistency and the unmixed consistency of the grease 60 is less than 50, so the softness of the portion of the grease 60 that is not in contact with the rolling element 30 and the retainer 40 is close to the softness of the portion of the grease 60 that is in contact with the rolling element 30 and the retainer 40. As a result, the difference in the bleeding of the base oil between the portion of the grease 60 that is in contact with the rolling element 30 or the retainer 40 and the portion that is not in contact with the rolling element 30 and the retainer 40 is reduced. Therefore, the rotation resistance of the rolling bearing 1 can be stabilized over a long period of time.

[0085] In addition, the ratio of the difference between the mixed consistency and the unmixed consistency of the grease 60 to the mixed consistency is less than 22.7%, so the softness of the portion of the grease 60 that is not in contact with the rolling element 30 and the retainer 40 is close to the softness of the portion of the grease 60 that is in contact with the rolling element 30 or the retainer 40. As a result, the difference in the bleeding of the base oil between the portion of the grease 60 that is in contact with the rolling element 30 or the retainer 40 and the portion that is not in contact with the rolling element 30 and the retainer 40 is reduced. Therefore, the rotation resistance of the rolling bearing 1 can be stabilized over a long period of time.

[0086] The thickener of the grease 60 includes urea. According to this configuration, a grease with high heat resistance can be obtained, so that a rolling bearing 1 with low rotation resistance and high durability can be formed. In addition, in general, in a grease using urea as a thickener, the difference between the mixed consistency and the unmixed consistency tends to become large. By adjusting the selection of the type of urea or the mixing of multiple types of urea, the conditions for generating urea, additives, etc., a grease that satisfies the above-mentioned consistency conditions can be obtained.

[0087] The unmixed consistency of the grease 60 after being left at 85° C. for 18 hours is greater than 158, so that the degree of hardening of the grease 60 can be set to such a degree that even if the grease 60 is exposed to high temperature or left for a long time, the base oil can be smoothly exuded. Therefore, a rolling bearing 1 with high durability can be formed.

[0088] Furthermore, according to the rotating device 2 of this embodiment, the rolling bearing 1 is provided with both ensuring durability and reducing rotational resistance, thereby achieving a longer life of the rotating device 2 and saving power of the rotating device 2 by reducing the rotational resistance of the shaft 3 to the frame 4.

[0089] In the first embodiment, the recessed portion 24 extends in a curved shape in the longitudinal section of the rolling bearing 1, but the present invention is not limited to this configuration. Figure 5As shown in FIG. 1 , the recess 24A may be formed by defining a rectangular space on the longitudinal section of the rolling bearing 1. That is, the recess 24A includes: a bottom surface 24Aa extending in the axial direction; a first step surface 24Ab extending from the end edge of the bottom surface 24Aa on the inner side in the axial direction to the inner side in the radial direction and facing upward; and a second step surface 24Ac extending from the end edge of the bottom surface 24Aa on the outer side in the axial direction to the inner side in the radial direction and facing downward. In this case, the grease 60 is restricted from being displaced inward in the axial direction from the initial state by contacting the first step surface 24Ab, thereby achieving the same effect as the first embodiment. In addition, the grease 60 is restricted from being displaced outward in the axial direction by contacting the second step surface 24Ac, thereby achieving the same effect as the first embodiment. In addition, in this modified example, it is also desirable that the grease 60 also contacts the ridge 25A of the end edge formed on the outer ring raceway surface 23 side (inward in the axial direction) of the recess 24A.

[0090] In the first embodiment, the recessed portion 24 is opened only on the inner peripheral surface 22b, but the present invention is not limited to this configuration. Figure 6 As shown, the recess 24B may be provided without spacing in the axial direction relative to the end face 22a facing upward, and open at the inner peripheral surface 22b and the end face 22a facing upward. In the example shown in the figure, the recess 24B has: an outer surface 24Ba, which faces a direction inclined toward the outer side in the axial direction relative to the radial direction (inward and upward in the radial direction, or upward); and a cylindrical surface 24Bc, which faces the inner side in the radial direction. The grease 60 contacts the outer surface 24Ba and the cylindrical surface 24Bc. In addition, in this modification, it is also ideal that the grease 60 also contacts the ridge 25B of the end edge formed on the outer ring raceway surface 23 side (inward in the axial direction) in the recess 24B.

[0091] Furthermore, if Figure 7 As shown, the grease 60 may also contact the sealing member 50 through the opening on the end face 22a of the recess 24B. In the example shown in the figure, the grease 60 contacts the seat portion 51 in the sealing member 50 which is configured in a manner to block the opening on the end face 22a of the recess 24B. However, the grease 60 may contact the extension portion 52 and the flat portion 53 in addition to the seat portion 51. In this case, the grease 60 may or may not contact the ridge portion 25B. In addition, the grease 60 contacts only the cylindrical surface 24Bc in the recess 24B. However, the grease 60 may contact the outer surface 24Ba in addition to the cylindrical surface 24Bc.

[0092] In addition, if Figure 8As shown, the recess 124 may also be formed in a manner that its entirety faces a direction that is inclined toward the outside of the axial direction relative to the radial direction (inside and above in the radial direction, or above). That is, the recess 124 may not have a portion extending in the axial direction. In the illustrated example, the recess 124 has an inclined surface 124a extending from the ridge 25C formed on the end edge of the outer ring raceway surface 23 side (inside in the axial direction) to the opening edge on the end surface 22a. The inclined surface 124a extends from the ridge 25C to the outside of the radial direction and the outside of the axial direction. In the illustrated example, the inclined surface 124a is a concave curved surface that is continuous throughout the entirety. However, the inclined surface only needs to extend from the ridge 25C in a direction that is inclined relative to the axial direction, and may also be formed by multiple discontinuous surfaces, or may be a conical surface that extends at a certain inclination angle relative to the axial direction. Furthermore, a portion of the inclined surface may also extend in the radial direction.

[0093] exist Figure 8 In the variation shown, the grease 60 contacts from the inclined surface 124a to the ridge 25C. Furthermore, in the variation, the grease 60 also contacts the portion of the inner circumferential surface of the protrusion 22 of the outer ring 20 between the ridge 25C and the outer ring raceway 23. That is, the grease 60 contacts from the portion between the ridge 25C and the outer ring raceway 23 to the inclined surface 124a in a manner that passes over the ridge 25C in the axial direction. With this structure, in the process of the base oil seeping from the grease 60 reaching the outer ring raceway 23, it is not necessary to pass over the ridge 25C, thereby suppressing the insufficient supply of the base oil of the grease 60 to the rolling element 30. In addition, in the variation, Figure 7 In the third modification shown, similarly, the grease 60 comes into contact with the sealing member 50 through the opening on the end surface 22a of the recessed portion 124. However, in this modification, the grease 60 may not come into contact with the sealing member 50.

[0094] In the first embodiment, the recess 24 extends continuously over the entire circumferential direction, but the present invention is not limited to this configuration. The recess may be formed discontinuously in the circumferential direction with a discontinuity formed in at least a portion of the circumferential direction.

[0095] In the first embodiment, the seat portion 51 of the sealing member 50 protrudes radially inward from the end face 22a of the protruding portion 22 of the outer ring 20 in a plan view, but it is desirable that the seat portion is configured so as not to protrude radially inward from the end face 22a of the protruding portion 22 in a plan view. According to this configuration, even if the outer ring contact portion 61 of the grease 60 spreads outward in the axial direction and exceeds the inner peripheral edge of the end face 22a, the grease 60 can be prevented from adhering to the seat portion. Therefore, the grease 60 can be prevented from contacting the contact portion between the outer ring 20 and the seat portion. As a result, the grease 60 can be prevented from leaking to the outside of the sealing member through the contact portion between the outer ring 20 and the seat portion due to the capillary phenomenon.

[0096] In addition, in the first embodiment, the grease 60 does not contact the seat portion 51 and the extension portion 52 of the sealing member 50, but the present invention is not limited to this configuration. The grease may contact at least one of the seat portion 51 and the extension portion 52 of the sealing member 50. If the area of ​​the contact portion of the sealing member is larger than the contact area of ​​the grease with the extension portion 52 and the seat portion 51, the above-mentioned effect is achieved.

[0097] In addition, as a method of fixing the sealing member 50, in addition to the method of press-fitting and fixing it to the raceway ring (outer ring 20) as in the present 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-shaped ring, but in this case, the position of the sealing member 50 is close to the inside in the axial direction, which is not preferred. By press-fitting and fixing the sealing member 50, the sealing member 50 can be arranged further outside in the axial direction, and the amount of grease 60 can be increased. In addition, the recessed portion 24 can be provided further outside in the axial direction, so even if the grease 60 is applied to the recessed portion 24, it is difficult for the grease 60 to be rolled into the rolling element 30 or the raceway surface, and the rotation resistance of the rolling bearing can be reduced.

[0098] [Second embodiment] Next, refer to Fig. 9 The second embodiment is described below. The second embodiment is different from the first embodiment in that the rolling bearing 1A includes grease 160 instead of the grease 60 of the first embodiment. The configuration other than that described below is the same as that of the first embodiment.

[0099] Fig. 9 It is a longitudinal sectional view of a rolling bearing according to a second embodiment. like Fig. 9As shown, 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 protrusion 22 of the outer ring 20, and does not contact the inner ring 10, the sealing member 50, the rolling element 30, and the retainer 40. The outer ring contact portion 161 extends in the circumferential direction over the entire length of the grease 160. The outer ring contact portion 161 has a width in the axial direction over the entire circumferential direction. The outer ring contact portion 161 contacts the recess 24 of the inner circumferential surface 22b of the protrusion 22. It is desirable that the grease 160 also contacts at least a portion of the ridge portion 25. In the present embodiment, the outer ring contact portion 61 contacts the ridge portion 25 over the entire circumference. The outer ring contact portion 161 is arranged at a distance in the axial direction relative to the contact portion between the outer ring 20 and the seat portion 51 of the sealing member 50.

[0100] In this embodiment, the same effects as those of the first embodiment are achieved. In addition, in this embodiment, the grease 160 does not contact the sealing member 50, so when the sealing member 50 is assembled to the outer ring 20, the grease 160 is not pushed by the sealing member 50. As a result, the grease 160 can be suppressed from moving inward in the axial direction, and the grease 160 can be suppressed from contacting the rolling element 30 or the retainer 40 more than necessary. Therefore, the increase in the rotation resistance of the rolling bearing 1A can be suppressed.

[0101] In the second embodiment, the grease 160 extends in a circular ring shape, but the present invention is not limited to this configuration. The grease may extend in a circular arc shape with a discontinuous portion, or may include a plurality of granules arranged in a dotted manner throughout the entire circumference. When the grease includes a plurality of granules, the plurality of granules arranged in the circumferential direction may be integrated or separated from each other.

[0102] [Third Embodiment] Next, refer to Fig.10 The third embodiment will be described. The rolling bearing 1B of the third embodiment is different from the rolling bearing 1A of the second embodiment in that the grease 160A contacts the seal member 50 and the rolling element 30. The configuration other than that described below is the same as that of the second embodiment.

[0103] Fig.10 It is a longitudinal sectional view of a rolling bearing according to a third embodiment. like Fig.10As shown, the grease 160A further includes a sealing member contact portion 162 that contacts the flat portion 53 of the sealing member 50 on the outside in the axial direction and on the inside in the radial direction relative to the outer ring contact portion 161, and does not contact the inner ring 10. The sealing member contact portion 162 contacts only the flat portion 53 of the sealing member 50. Thus, the grease 160A does not contact the seat portion 51 and the extension portion 52 of the sealing member 50 that are located closer to the outer ring 20 than the flat portion 53. The grease 160A contacts the rolling element 30. The volume of the portion of the grease 160A that contacts the rolling element 30 is less than half of the volume of the grease 160A as a whole. In addition, the grease 160A may also contact the retainer 40.

[0104] In this embodiment, the same effects as those of the second embodiment are achieved. In addition, in this embodiment, since the grease 160A is in contact with the rolling element 30, the base oil of the grease 160A can be directly supplied to the rolling element 30. Therefore, an increase in the rotation resistance of the rolling bearing 1B can be suppressed.

[0105] In the third embodiment, similarly to the first embodiment, the grease 160A is prevented from spreading significantly toward the inner ring 10 and the rolling element 30 when the seal member 50 is assembled. Therefore, even if the grease 160A contacts the rolling element 30, the contact portion can be made sufficiently small compared to the conventional structure, thereby achieving a reduction effect of the rotational resistance.

[0106] In the third embodiment, the grease 160A extends in an annular shape, but the present invention is not limited to this configuration. The grease may extend in an arc shape with a discontinuous portion, or may include a plurality of granules arranged in a dotted manner throughout the entire circumference. When the grease includes a plurality of granules, the plurality of granules arranged in the circumferential direction may be integrated or separated from each other.

[0107] [Fourth embodiment] Next, a fourth embodiment will be described. The grease contacts only a portion of the recessed portion, which is in a direction inclined toward the outside in the axial direction relative to the radial direction (inside and above in the radial direction, or above) and is continuous with the ridge. For example, in the case where the recessed portion has a bottom surface extending in the axial direction, the grease contacts only a portion between the ridge and the bottom surface relative to the recessed portion. In addition, it is desirable that the grease contacts the sealing member. Thus, the grease is sandwiched by the sealing member and the recessed portion from both sides in the axial direction, and can maintain the initial shape for a long time.

[0108] [Fifth embodiment] Next, refer to Fig.11The fourth embodiment will be described. The rolling bearing 1C of the fourth embodiment is different from the rolling bearing 1 of the first embodiment in that the grease 260 contacts only the outer surface 24Ca of the recess 24C. The configuration other than that described below is the same as that of the first embodiment.

[0109] Fig.11 It is a longitudinal sectional view of a rolling bearing according to a fifth embodiment. like Fig.11 As shown, a recessed portion 24C is formed on the inner circumferential surface 22b of the protruding portion 22 of the outer ring 20, which is recessed toward the outer side in the radial direction. The recessed portion 24C is provided without spacing in the axial direction relative to the end face 22a of the protruding portion 22 facing upward, and is open at the inner circumferential surface 22b and the end face 22a facing upward. The recessed portion 24C includes: an outer surface 24Ca, which faces a direction inclined toward the outer side in the axial direction relative to the radial direction (inward and upward in the radial direction, or upward); and a cylindrical surface 24Cc, which faces the inner side in the radial direction. The outer surface 24Ca is a concave curved surface. The cylindrical surface 24Cc extends in the axial direction, and the end edge on the inner side in the axial direction is smoothly connected to the outer surface 24Ca in a tangentially continuous manner.

[0110] The grease 260 includes an outer ring contact portion 261 (raceway ring contact portion) that contacts the inner peripheral surface 22b of the protrusion 22 of the outer ring 20, and a seal member contact portion 262 that contacts the seal member 50 on the outer side in the axial direction and on the inner side in the radial direction of the outer ring contact portion 261. The outer ring contact portion 261 contacts the recess 24C of the inner peripheral surface 22b of the protrusion 22. The outer ring contact portion 261 contacts the recess 24C over the entire circumference. The outer ring contact portion 261 contacts only the outer surface 24Ca of the recess 24C. In this case, it is desirable that the outer ring contact portion 261 also contacts at least a portion of the ridge 25 of the inner peripheral surface 22b. However, the outer ring contact portion 261 may not contact the ridge 25 of the inner peripheral surface 22b. In the present embodiment, the seal member contact portion 262 is a portion of the grease 260 that contacts the flat surface 53 of the seal member 50. In the present embodiment, the grease 260 is also in contact with the seat portion 51 and the extension portion 52 of the sealing member 50. However, in the case where the grease 260 is in contact with at least one of the seat 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 of ​​the grease 260 with the extension portion 52 and the seat portion 51. In addition, the grease 260 may not be in contact with at least one of the seat portion 51 and the extension portion 52. The grease 260 is formed in such a manner that the cross-sectional area of ​​the cross section along the vertical plane of the common axis O gradually increases from the end portion on the outer side in the axial direction toward the inner side in the axial direction.

[0111] The grease 260 includes: a first annular portion 260a, which contacts the outer ring 20; and a second annular portion 260b, which 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 twice. The first annular portion 260a and the second annular portion 260b extend in a circumferential shape with the common axis O as the center. However, at least one of the first annular portion 260a and the second annular portion 260b may extend less than 360° with the common axis O as the center. The first annular portion 260a includes an outer ring contact portion 261. The second annular portion 260b is arranged on the side opposite to the outer ring 20 in the radial direction (i.e., the inner side in the radial direction) with respect to the first annular portion 260a. The second annular portion 260 b is connected to and integrated with the first annular portion 260 a on the outside in the axial direction. The second annular portion 260 b includes a seal member contact portion 262 .

[0112] In this embodiment, the same effects as those of the first embodiment are achieved. In addition, in this embodiment, the recessed portion 24C opens at the end surface 22a of the protruding portion 22 facing upward, and the grease 260 contacts only the outer surface 24Ca of the recessed portion 24C. With this configuration, it is possible to prevent the grease 260 or its base oil from flowing out from the recessed portion 24C toward the end surface 22a and leaking out from the gap between the end surface 22a and the seat portion 51 of the sealing member 50.

[0113] In addition, in the fifth embodiment, the first annular portion 260a and the second annular portion 260b extend in a circumferential shape, but are not limited to this configuration. At least one of the first annular portion and the second annular portion may also include granules arranged in a dotted shape throughout the entire circumference. In this case, the plurality of granules arranged in the circumferential direction may be integrated or separated from each other.

[0114] In the fifth embodiment, the grease 260 includes the first annular portion 260a and the second annular portion 260b, but the present invention is not limited to this configuration. Fig.12 As shown, the grease 260A may be formed by a single annular portion having the outer ring contact portion 261 and the seal member contact portion 262 .

[0115] [Sixth embodiment] Next, refer to Fig.13 The sixth embodiment will be described. The rolling bearing 1D of the sixth embodiment is different from the rolling bearing 1 of the first embodiment in that the grease 360 ​​is arranged in the axial direction along the recess 24D. The configuration other than that described below is the same as that of the first embodiment.

[0116] Fig.13 It is a longitudinal sectional view of a rolling bearing according to a sixth embodiment. like Fig.13 As shown in FIG. 1 , a recess 24D is formed on the inner circumferential surface 22b of the protruding portion 22 of the outer ring 20, which is recessed toward the outer side in the radial direction. The recess 24D is provided without spacing in the axial direction relative to the end face 22a of the protruding portion 22 facing upward, and is open at the inner circumferential surface 22b and the end face 22a facing upward. The recess 24D includes: an outer surface 24Da, which faces a direction inclined toward the outer side in the axial direction relative to the radial direction (inward and upward in the radial direction, or upward); and a cylindrical surface 24Dc, which faces the inner side in the radial direction. The outer surface 24Da is a concave curved surface. The cylindrical surface 24Dc extends in the axial direction, and the end edge on the inner side in the axial direction is smoothly connected to the outer surface 24Da in a continuous tangent manner. The recess 24D extends in the axial direction in a longitudinal section of the rolling bearing 1D in a manner that the width in the axial direction is larger than the depth in the radial direction. Furthermore, the outer 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.

[0117] The grease 360 ​​includes an outer ring contact portion 361 that contacts the inner peripheral surface 22b of the protrusion 22 of the outer ring 20. The outer ring contact portion 361 contacts the recess 24D of the inner peripheral surface 22b of the protrusion 22. The outer ring contact portion 361 contacts the recess 24D over the entire circumference. The outer ring contact portion 361 contacts the outer surface 24Da and the cylindrical surface 24Dc of the recess 24D. The outer ring contact portion 361 also contacts at least a portion of the ridge 25 of the inner peripheral surface 22b. The grease 360 ​​contacts the sealing member 50. In the present embodiment, the grease 360 ​​contacts the seat portion 51 and the extension portion 52 of the sealing member 50.

[0118] The grease 360 ​​is arranged in the axial direction along the recess 24D on the longitudinal section of the rolling bearing 1D. The grease 360 ​​includes a first annular portion 360a, a second annular portion 360b, and a third annular portion 360c arranged side by side in the axial direction. The first annular portion 360a, the second annular portion 360b, and the third annular portion 360c are formed by applying the grease three times. The first annular portion 360a, the second annular portion 360b, and the third annular portion 360c extend in a circumferential shape with the common axis O as the center. However, at least any one of the first annular portion 360a, the second annular portion 360b, and the third annular portion 360c may extend less than 360° with the common axis O as the center. The first annular portion 360a contacts the outer surface 24Da of the recess 24D and the cylindrical surface 24Dc. The second annular portion 360b is connected to the first annular portion 360a on the outside in the axial direction. The second annular portion 360b contacts the cylindrical surface 24Dc of the recessed portion 24D. The third annular portion 360c is connected to the second annular portion 360b on the outside in the axial direction. The third annular portion 360c contacts the cylindrical surface 24Dc of the recessed portion 24D and the sealing member 50.

[0119] In this embodiment, the same effects as those of the first embodiment are achieved. In addition, in this embodiment, the grease 360 ​​is arranged along the recess 24D in the axial direction, so that the displacement of the grease 360 ​​in the axial direction can be effectively restricted by the recess 24D, and the displacement of the grease 360 ​​and the contact with the rolling element 30 or the retainer 40 by more than the desired amount can be suppressed. Furthermore, the shape and position of the grease 360 ​​are unlikely to change due to vibration during transportation or long-term storage (especially storage in a high temperature environment). Therefore, it is possible to provide a rolling bearing 1D that suppresses the change of the rotation resistance from the initial stage of manufacturing.

[0120] In addition, in the sixth embodiment, the first annular portion 360a, the second annular portion 360b, and the third annular portion 360c extend in a circumferential shape, but are not limited to this configuration. At least any one of the first annular portion, the second annular portion, and the third annular portion may also include granules arranged in a dotted shape throughout the entire circumference. In this case, the plurality of granules arranged in the circumferential direction may be integrated or separated from each other.

[0121] In the sixth embodiment, the grease 360 ​​includes the first annular portion 360a, the second annular portion 360b, and the third annular portion 360c, but the present invention is not limited to this configuration. Fig.14 As shown, the grease 360A may also extend in the axial direction along the recess 24D in the longitudinal section of the rolling bearing 1D.

[0122] In the sixth embodiment, the grease 360 ​​contacts the ridge 25 of the inner peripheral surface 22b of the protrusion 22 of the outer ring 20, but the present invention is not limited to this configuration. Fig.15 As shown, the grease 360B may not contact the ridge 25. In this case, the first annular portion 360a may be formed smaller than the second annular portion 360b and the third annular portion 360c in the longitudinal section of the rolling bearing 1D so as not to contact the ridge 25. According to this configuration, the base oil of the grease 360B may not be supplied to the rolling element 30, but the total amount of the grease 360B can be increased, thereby providing the rolling bearing 1D with higher durability.

[0123] [Seventh embodiment] Next, refer to Fig.16 The seventh embodiment will be described. The rolling bearing 1E of the seventh embodiment is different from the rolling bearing 1 of the first embodiment in the following point: the deepest part in the radial direction of the recess 24E is formed on the inner side of the axial direction than the middle position of the recess 24E in the axial direction. In addition, the structure other than that described below is the same as that of the first embodiment.

[0124] Fig.16 It is a longitudinal sectional view of a rolling bearing according to a seventh embodiment. like Fig.16 As shown, the recess 24E is provided at intervals in the axial direction relative to the outer ring raceway surface 23. The recess 24E is provided at intervals in the axial direction relative to the end surface 22a facing upward. The recess 24E is formed in a manner that the width in the axial direction is larger than the depth in the radial direction in the longitudinal section of the rolling bearing 1E. The recess 24E includes: an outer surface 24Ea, which faces a direction inclined toward the outer side in the axial direction relative to the radial direction (inward and upward in the radial direction, or upward); an inner surface 24Eb, which faces a direction inclined toward the inner side in the axial direction relative to the radial direction (inward and downward in the radial direction, or downward); and a cylindrical surface 24Ec, which faces the inner side in the radial direction. In this embodiment, the outer surface 24Ea and the inner surface 24Eb face the axial direction. As a result, the recess 24E is formed in a rectangular shape in the longitudinal section of the rolling bearing 1E. The cylindrical surface 24Ec is located at the deepest position in the radial direction of the recess 24E, and extends axially across the middle position of the recess 24E in the axial direction. Thus, the deepest part in the radial direction of the recess 24E is formed axially inward of the middle position of the recess 24E in the axial direction.

[0125] The grease 460 includes an outer ring contact portion 461 (raceway ring contact portion) that contacts the inner peripheral surface 22b of the protrusion 22 of the outer ring 20, and a seal member contact portion 462 that contacts the flat surface 53 of the seal member 50 on the outer side in the axial direction and on the inner side in the radial direction of the outer ring contact portion 461. The outer ring contact portion 461 contacts the recess 24E of the inner peripheral surface 22b of the protrusion 22. The outer ring contact portion 461 contacts the recess 24E over the entire circumference. The outer ring contact portion 461 contacts the outer surface 24Ea and the cylindrical surface 24Ec of the recess 24E. The outer ring contact portion 461 also contacts at least a portion of the ridge 25 of the inner peripheral surface 22b. The grease 460 does not contact the inner surface 24Eb of the recess 24E. However, the grease 460 may contact the inner surface 24Eb of the recess 24E. In the present embodiment, the seal member contact portion 462 is a portion of the grease 460 that contacts the flat surface portion 53 of the seal member 50. In the present embodiment, the grease 460 does not contact the seat portion 51 and the extension portion 52 of the seal member 50. However, the grease 460 may contact at least one of the seat portion 51 and the extension portion 52 of the seal member 50. In this case, it is desirable that the area of ​​the seal member contact portion 462 is larger than the contact area of ​​the grease 460 with the extension portion 52 and the seat portion 51. The grease 460 extends from the outer ring contact portion 461 toward the seal member contact portion 462 toward the outside in the axial direction and toward the inside in the radial direction.

[0126] In this embodiment, the same effect as that of the first embodiment is achieved. In addition, in this embodiment, the deepest part in the radial direction of the recess 24E is formed on the inner side in the axial direction of the recess 24E than the middle position in the axial direction of the recess 24E. According to this structure, when the grease 460 is ejected from the nozzle and applied to a predetermined part, it is easy to insert the tip of the nozzle from the outside of the rolling bearing 1E to the inside of the outer ring 20 and the inner ring 10 and approach the recess 24E. Therefore, in the rolling bearing 1E with a small diameter, its productivity can be improved. In addition, it is easy to make the nozzle close to the recess 24E, so that the grease 460 can be applied with good accuracy, and the grease 460 can be prevented from contacting the rolling element 30 or the like more than the desired amount. Therefore, it is possible to reduce the rotation resistance of the rolling bearing 1E.

[0127] In the seventh embodiment, the recessed portions 24E are formed vertically symmetrically in the longitudinal section of the rolling bearing 1E, but the present invention is not limited to this configuration. Fig.17 and Fig.18 As shown in FIG. 1 , the concave portions 124E and 224E may be formed asymmetrically in the longitudinal section of the rolling bearing 1E. Fig.17 and Fig.18 The modified example shown will be described.

[0128] exist Fig.17 In the first modified example shown, the recess 124E is formed in a longitudinal section of the rolling bearing 1E in such a manner that the width in the axial direction is larger than the depth in the radial direction. The recess 124E includes: an outer surface 124Ea, which faces a direction inclined toward the outer side in the axial direction relative to the radial direction (inward and upward in the radial direction, or upward); and an inner surface 124Eb, which faces a direction inclined toward the inner side in the axial direction relative to the radial direction (inward and downward in the radial direction, or downward). The outer surface 124Ea is a curved surface that is recessed toward the inner side in the axial direction and the outer side in the radial direction. The inner surface 124Eb is a conical surface that extends from the end edge of the outer side in the axial direction of the outer surface 124Ea toward the outer side in the axial direction and the inner side in the radial direction. The connection portion between the outer surface 124Ea and the inner surface 124Eb is located further inward in the axial direction than the middle position in the axial direction of the recess 124E. Thus, the deepest portion in the radial direction of the recess 124E is formed on the inner side in the axial direction relative to the middle position in the axial direction of the recess 124E.

[0129] The grease 460A includes an outer ring contact portion 461A (raceway ring contact portion) that contacts the inner peripheral surface 22b of the protrusion 22 of the outer ring 20, and a seal member contact portion 462A that contacts the flat surface 53 of the seal member 50 on the outer side in the axial direction and on the inner side in the radial direction of the outer ring contact portion 461A. The outer ring contact portion 461A contacts the recess 124E of the inner peripheral surface 22b of the protrusion 22. The outer ring contact portion 461A contacts the recess 124E over the entire circumference. The outer ring contact portion 461A contacts the outer surface 124Ea of the recess 124E. The outer ring contact portion 461A contacts the inner surface 124Eb of the recess 124E. The outer ring contact portion 461A contacts the connecting portion between the outer surface 124Ea and the inner surface 124Eb of the recess 124E. The grease 460A does not contact the ridges 25 of the inner peripheral surface 22b. However, the grease 460A may contact the ridges 25 of the inner peripheral surface 22b.

[0130] In this modification, the seal member contact portion 462A is a portion of the grease 460A that contacts the flat portion 53 of the seal member 50. In this modification, the grease 460A does not contact the seat portion 51 and the extension portion 52 of the seal member 50. However, the grease 460A may contact at least one of the seat portion 51 and the extension portion 52 of the seal member 50. In this case, it is desirable that the area of ​​the seal member contact portion 462A is larger than the contact area of ​​the grease 460A with the extension portion 52 and the seat portion 51. The grease 460A may be formed in such a manner that the cross-sectional area of ​​the cross section along the perpendicular plane of the common axis O gradually increases from the end portion on the outer side in the axial direction toward the inner side in the axial direction. The grease 460A extends from the outer ring contact portion 461A toward the seal member contact portion 462A toward the outer side in the axial direction and toward the inner side in the radial direction. The grease 460A extends from the outer ring contact portion 461A along the inward surface 124Eb of the recess 124E.

[0131] exist Fig.18In the second modified example shown, the recess 224E is formed in a longitudinal section of the rolling bearing 1E in such a manner that the width in the axial direction is larger than the depth in the radial direction. The recess 224E includes: an outer surface 224Ea, which faces a direction inclined toward the outer side in the axial direction relative to the radial direction (inward and upward in the radial direction, or upward); and an inner surface 224Eb, which faces a direction inclined toward the inner side in the axial direction relative to the radial direction (inward and downward in the radial direction, or downward). The outer surface 224Ea is a plane facing outward in the axial direction. The inner surface 224Eb is a conical surface extending from the end edge of the outer side in the radial direction of the outer surface 224Ea toward the outer side in the axial direction and the inner side in the radial direction. The connection portion between the outer surface 224Ea and the inner surface 224Eb is located further inward in the axial direction than the middle position in the axial direction of the recess 224E. Thus, the deepest portion in the radial direction of the recess 224E is formed on the inner side in the axial direction relative to the middle position in the axial direction of the recess 224E.

[0132] The grease 460B includes an outer ring contact portion 461B (raceway ring contact portion) that contacts the inner peripheral surface 22b of the protrusion 22 of the outer ring 20, and a seal member contact portion 462B that contacts the flat surface 53 of the seal member 50 on the outer side in the axial direction and on the inner side in the radial direction of the outer ring contact portion 461B. The outer ring contact portion 461B contacts the recess 224E of the inner peripheral surface 22b of the protrusion 22. The outer ring contact portion 461B contacts the recess 224E over the entire circumference. The outer ring contact portion 461B contacts the outer surface 224Ea of the recess 224E. The outer ring contact portion 461B contacts the inner surface 224Eb of the recess 224E. The outer ring contact portion 461B does not contact the connection between the outer surface 224Ea and the inner surface 224Eb of the recess 224E. The lubricating grease 460B does not contact the ridge portion 25 of the inner peripheral surface 22b. However, the lubricating grease 460B may contact the ridge portion 25 of the inner peripheral surface 22b.

[0133] In this modification, the seal member contact portion 462B is a portion of the grease 460B that contacts the flat portion 53 of the seal member 50. In this modification, the grease 460B does not contact the seat portion 51 and the extension portion 52 of the seal member 50. However, the grease 460B may contact at least one of the seat portion 51 and the extension portion 52 of the seal member 50. In this case, it is desirable that the area of ​​the seal member contact portion 462B is larger than the contact area of ​​the grease 460B with the extension portion 52 and the seat portion 51. The grease 460B may be formed in such a manner that the cross-sectional area of ​​the cross section along the perpendicular plane of the common axis O gradually increases from the end portion on the outer side in the axial direction toward the inner side in the axial direction. The grease 460B extends from the outer ring contact portion 461B toward the seal member contact portion 462B toward the outer side in the axial direction and toward the inner side in the radial direction. The grease 460B extends from the outer ring contact portion 461B along the inward surface 224Eb of the recessed portion 224E.

[0134] The rolling bearings 1E according to these modified examples also have the same effects as those of the seventh embodiment.

[0135] [Eighth embodiment] Next, refer to Fig.19 The eighth embodiment will be described. The shape of the inner peripheral surface 22b of the protrusion 22 of the outer ring 20 of the rolling bearing 1F of the eighth embodiment is different from that of the rolling bearing 1 of the first embodiment. The configuration other than that described below is the same as that of the first embodiment.

[0136] Fig.19 It is a longitudinal sectional view of a rolling bearing according to an eighth embodiment. like Fig.19 As shown, the inner circumferential surface 22b of the protrusion 22 of the outer ring 20 has a recess 24 and a connection surface 26. The recess 24 is arranged at a distance in the axial direction relative to the end surface 22a of the protrusion 22 facing upward. The connection surface 26 is formed between the recess 24 and the end surface 22a of the protrusion 22 facing upward. The connection surface 26 extends in the axial direction and faces the inner side in the radial direction. The connection surface 26 is located on the outer side in the radial direction in a manner that is farther away from the inner ring 10 in the radial direction than the end edge of the outer ring raceway surface 23 in the axial direction.

[0137] In this embodiment, the same effects as those of the first embodiment are achieved. In addition, in this embodiment, the inner circumferential surface 22b of the protruding portion 22 of the outer ring 20 has a connecting surface 26 formed between the recess 24 and the end surface 22a. The connecting surface 26 is located radially outward of the end edge of the outer ring raceway surface 23 in the axial direction. According to this configuration, when the tip of the nozzle is inserted from the outside of the rolling bearing 1F to the inside of the outer ring 20 and the inner ring 10 in order to apply the grease 60 to a predetermined position by ejecting it from the nozzle, it is possible to make it difficult for the connecting surface 26 to contact the nozzle. Therefore, when applying the grease 60, it is easy to bring the nozzle close to the recess 24, so that the productivity of the rolling bearing 1F with a small diameter can be improved. In addition, it is easy to bring the nozzle close to the recess 24, so that the grease 60 can be applied with good accuracy, and it is possible to prevent the grease 60 from contacting the rolling element 30 and the like more than the desired amount. Therefore, it is possible to reduce the rotation resistance of the rolling bearing 1F.

[0138] [Ninth embodiment] Next, refer to Fig. 20 The ninth embodiment will be described. The shape of the inner peripheral surface 22b of the protrusion 22 of the outer ring 20 of the rolling bearing 1G of the ninth embodiment is different from that of the rolling bearing 1 of the first embodiment. The configuration other than that described below is the same as that of the first embodiment.

[0139] Fig. 20 It is a longitudinal sectional view of a rolling bearing according to a ninth embodiment. like Fig. 20As shown, the inner circumferential surface 22b of the protrusion 22 of the outer ring 20 has a recess 224 and an inclined portion 227. The recess 224 is provided in the axial direction without spacing relative to the upward end surface 22a of the protrusion 22, and is open at the inner circumferential surface 22b and the upward end surface 22a. The recess 224 has: an outer surface 224a, which faces a direction inclined toward the outer side in the axial direction relative to the radial direction (inward and upward in the radial direction, or upward); and a cylindrical surface 224c, which faces the inner side in the radial direction. The outer surface 224a is a concave curved surface. The radial inner edge of the outer surface 224a is located radially outside the axial end edge of the outer ring raceway surface 23. The cylindrical surface 224c extends in the axial direction and is connected to the axial outer edge of the outer surface 224a. The inclined portion 227 extends from the end edge of the outer ring raceway surface 23 side of the recess 224 (the end edge on the radial inner side of the outer surface 224a) to the outer ring raceway surface 23 side at an inclination relative to the radial direction and the axial direction. That is, the inclined portion 227 extends from the ridge 25 of the inner peripheral surface 22b to the inner side in the radial direction and the inner side in the axial direction. In the present embodiment, the inclined portion 227 extends linearly from the end edge of the recess 224 in the longitudinal section of the rolling bearing 1G. However, the inclined portion only needs to extend at an inclination steeper than the recess 224 in the radial direction with the connection portion between the inclined portion and the recess 224 as the boundary in the longitudinal section of the rolling bearing 1G. The inclined portion 227 is provided at a distance in the axial direction relative to the outer ring raceway surface 23.

[0140] The grease 560 includes an outer ring contact portion 561 that contacts the inner peripheral surface 22b of the protrusion 22 of the outer ring 20. The outer ring contact portion 561 contacts the recess 224 of the inner peripheral surface 22b of the protrusion 22. The outer ring contact portion 561 contacts the recess 224 over the entire circumference. The outer ring contact portion 561 contacts the outer surface 224a and the cylindrical surface 224c of the recess 224. The outer ring contact portion 561 also contacts at least a portion of the ridge 25 of the inner peripheral surface 22b. In addition, it is ideal that the outer ring contact portion 561 does not contact the inclined portion 227. In addition, the grease 560 may also contact the sealing member 50.

[0141] In this embodiment, the same effects as those of the first embodiment are achieved. In addition, in this embodiment, the inner circumferential surface 22b of the protruding portion 22 of the outer ring 20 has an inclined portion 227 extending from the end edge of the recess 224 on the outer ring raceway 23 side to the outer ring raceway 23 side at an angle relative to the radial direction and the axial direction. According to this structure, even if the end of the recess 224 on the outer ring raceway 23 side extends in the radial direction, the inner circumferential surface 22b gradually inclines from the recess 224 toward the outer ring raceway 23, thereby promoting the base oil seeping from the grease 560 to flow from the recess 224 along the inclined portion 227 toward the outer ring raceway 23. Therefore, even if the grease 560 is not arranged close to the outer ring raceway 23, insufficient supply of the base oil of the grease 560 to the rolling element 30 can be suppressed.

[0142] In addition, if Fig.21 As shown, the grease 560A may be arranged so as not to protrude from the inner side of the recess 224 to the inclined portion 227 side (inner side) in the radial direction. That is, 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. With this configuration, it is possible to suppress the grease 560A from contacting the rolling element 30. On the other hand, since the amount of grease 560A applied is reduced, the effect of suppressing the insufficient supply of the base oil of the grease 560A to the rolling element 30 as described above can be appropriately obtained.

[0143] In the ninth embodiment, the recessed portion 224 is provided without spacing in the axial direction relative to the upward end surface 22a of the protruding portion 22, but the present invention is not limited to this configuration. Fig. 22 As shown, the recess 224A may also be provided at intervals in the axial direction relative to the end face 22a facing upward. In addition, in the example shown in the figure, the recess 224A has an outer surface 224Aa that is inclined toward the outer side of the axial direction relative to the radial direction, and an inner surface 224Ab that is inclined toward the inner side of the axial direction relative to the radial direction, but the shape of the recess is not particularly limited. [Example]

[0144] Hereinafter, the present invention will be described in detail by way of Examples, but the present invention is not limited to the following description.

[0145] The viscosity of the grease in this example was measured at 40° C. in accordance with JIS K2283. The consistency of the grease in this example was measured by the method specified in JIS K2220.

[0146] Greases of Examples 1 to 5 and Comparative Examples 1 to 4 were prepared as follows.

[0147] <Example 1> Ester oil and PAO are mixed at a mass ratio (ester oil / PAO)>1 to achieve a kinematic viscosity of 44 mm 2 / s base oil. Alicyclic urea was synthesized as a thickener in the base oil to obtain a grease with a mixed consistency of 228, an unmixed consistency of 227, and an unmixed consistency of 188 after high temperature storage.

[0148] <Example 2> The same base oil and thickener as in Example 1 were used, and the ratio of the thickener to the base oil was adjusted to obtain a grease having a mixed consistency of 261, an unmixed consistency of 255, and an unmixed consistency of 210 after being stored at high temperature.

[0149] <Example 3> Ether oil and ester oil are mixed at a mass ratio (ether oil / ester oil)>1 to a kinematic viscosity of 80 mm 2 / s base oil. Alicyclic urea was synthesized in the base oil to obtain a grease with a mixed consistency of 290, an unmixed consistency of 274, and an unmixed consistency of 282 after high temperature storage.

[0150] <Example 4> With PAO monomer as the kinematic viscosity 48mm 2 / s base oil. Alicyclic urea and aliphatic urea were synthesized in the base oil to obtain a grease with a mixed consistency of 199, an unmixed consistency of 197, and an unmixed consistency of 200 after high temperature storage.

[0151] <Example 5> Taking ester oil monomer as kinematic viscosity 100mm 2 / s base oil. Alicyclic urea and aliphatic urea were synthesized in the base oil to obtain a grease with a mixed consistency of 265, an unmixed consistency of 245, and an unmixed consistency of 244 after high temperature storage.

[0152] <Comparative Example 1> With PAO monomer as the kinematic viscosity 48mm 2 / s base oil. Alicyclic urea and aliphatic urea were synthesized as thickeners in the base oil to obtain a grease with a mixed consistency of 220, an unmixed consistency of 170, and an unmixed consistency of 158 after high temperature storage.

[0153] <Comparative Example 2> PAO and ester oil are mixed at a mass ratio (PAO / ester oil)>1 to a kinematic viscosity of 22 mm 2 / s base oil. Alicyclic urea and aliphatic urea were synthesized as thickeners in the base oil to obtain a grease with a mixed consistency of 232, an unmixed consistency of 178, and an unmixed consistency of 149 after high temperature storage.

[0154] <Comparative Example 3> The same base oil and thickener as in Example 1 were used, and the ratio of the thickener to the base oil was adjusted to obtain a grease having a mixed consistency of 295, an unmixed consistency of 287, and an unmixed consistency of 236 after being stored at high temperature.

[0155] <Comparative Example 4> Mineral oil and PAO were mixed at a mass ratio of (mineral oil / PAO) ≒ 1 to achieve a kinematic viscosity of 52 mm 2 / s base oil. Alicyclic urea and aliphatic urea were synthesized as thickeners in the base oil to obtain a grease with a mixed consistency of 248, an unmixed consistency of 164, and an unmixed consistency of 155 after high temperature storage.

[0156] The greases of Examples 1 to 5 and Comparative Examples 1, 2, and 4 were subjected to a rolling bearing durability test under the following conditions. In addition, when the grease of Comparative Example 3 was used in the rolling bearing described below, the deviation of the rotational resistance of each rolling bearing was larger than the predetermined required value, and the rotational resistance varied with the operating time, so it was determined to be unsuitable as a grease for rolling bearings and was excluded from the endurance test.

[0157] (Shape of rolling bearing) A rolling bearing having an outer ring with an outer diameter of 8 mm, an inner ring with an inner diameter of 3 mm, and a height (thickness in the axial direction) of 4 mm was used.

[0158] (Grease configuration) 12 mg of grease was applied in the shape of the grease 60 of the first embodiment described above.

[0159] (Durability Evaluation Method) Two rolling bearings using the same grease were installed for one fan motor (rated speed 25000 rpm). Five fan motors were prepared for each grease of Examples 1 to 5 and Comparative Examples 1 and 2, and operated continuously in a high temperature tank at 85°C. The operating conditions and the presence of abnormal noise were confirmed every 500 hours. The evaluation results are shown in Table 1.

[0160] [Table 1]

[0161] When the grease of Comparative Example 1 was used, abnormal noise was confirmed in 3 of the 5 fan motors after 3000 hours of operation. When the grease of Comparative Example 2 was used, 1 of the 5 fan motors stopped after 2000 hours of operation, and 2 of them stopped after 2500 hours of operation. On the other hand, when the greases of Examples 1 to 5 were used, the 5 fan motors did not generate abnormal noise and operated stably even after 5000 hours of operation. From the above, it is obvious that if the unmixed consistency of the grease is greater than 178 and less than 287, the deviation of the rotational resistance of each rolling bearing can be suppressed, and at the same time, the durability of the rolling bearing can be improved. Furthermore, it is obvious that if the unmixed consistency of the grease satisfies the above conditions and the difference between the mixed consistency and the unmixed consistency is less than 50, the durability of the rolling bearing can be reliably improved. It is also clear that if the unmixed consistency of the grease satisfies the above-mentioned conditions and the ratio of the difference between the mixed consistency and the unmixed consistency to the mixed consistency is less than 22.7%, the durability of the rolling bearing can be reliably improved.

[0162] In addition, the present invention is not limited to the above-mentioned embodiment described with reference to the drawings, and various modifications are conceivable within the technical scope of the present invention. For example, in the above-mentioned embodiment, the inner ring 10 is provided as a rotating ring, and the outer ring 20 is provided as a fixed ring. Furthermore, the grease 60, 160, 160A, 260, 260A, 360, 360A, 360B, 460, 460A, 460B, 560, 560A is in contact with the outer ring 20 as a fixed ring. However, the raceway ring that the grease is in contact with may not be a fixed ring. That is, the inner ring may be provided as a fixed ring, the outer ring may be provided as a rotating ring, and the grease may be in contact with the inner ring as a fixed ring. In addition, the inner ring may be provided as a fixed ring, the outer ring may be provided as a rotating ring, and the grease may be in contact with the outer ring as a rotating ring.

[0163] In the above-mentioned embodiments, the grease 60, 160, 160A, 260, 260A, 360, 360A, 360B, 460, 460A, 460B, 560, 560A contacts the entire circumference of the recess, but the present invention is not limited to this configuration. The grease may contact only a portion of the recess in the circumferential direction.

[0164] In addition, the shape of the sealing component and the form of the contact portion between the sealing component and the grease are not limited to the above-mentioned embodiment. For example, the sealing component may not have a protruding portion, and the planar portion may be formed in a manner extending from the base portion to the inner side in the radial direction. For example, the grease may be in contact with both the planar portion and the protruding portion of the sealing component, or may be in contact with the protruding portion instead of the planar portion. Since the grease has the properties of the above-mentioned embodiment, as long as the grease is in contact with at least one of the planar portion and the protruding portion, it is easy to maintain the shape of the portion of the grease 60 that is not in contact with the rolling element 30 and the retainer 40 in the initial shape. Therefore, it is possible to suppress the shape of the grease 60 from being different for each rolling bearing 1 and the deviation in the rotational resistance.

[0165] In the above-mentioned embodiment, the grease 60, 160, 160A, 260, 260A, 360, 360A, 360B, 460, 460A, 460B, 560, 560A does not contact the inner ring 10 and the retainer 40, but the present invention is not limited to this configuration. As described above, in the above-mentioned embodiment, it is possible to suppress the grease from spreading significantly toward the inner ring 10 side and the rolling element 30 side when the sealing member 50 is assembled. Therefore, even if the grease contacts at least one of the inner ring 10 and the retainer 40, the contact portion can be made sufficiently small compared to the conventional structure, thereby achieving the effect of reducing the rotation resistance.

[0166] In the above embodiment, the grease is arranged on the side opposite to the annular portion 41 of the retainer 40 sandwiching the rolling elements 30 in the axial direction. However, the grease may also be arranged on the annular portion 41 side of the retainer 40 relative to the rolling elements 30 in the axial direction.

[0167] In addition, the rolling bearing may be provided with grease other than the grease 60, 160, 160A, 260, 260A, 360, 360A, 360B, 460, 460A, 460B, 560, 560A. In the above-mentioned embodiment, the grease is arranged on the side opposite to the annular portion 41 of the retainer 40 with respect to the rolling element 30 in the axial direction, but the grease may also be arranged on the annular portion 41 side of the retainer 40 with respect to the rolling element 30 in the axial direction. For example, the rolling bearing may further include grease applied to the grease hole or the lower end surface of the retainer.

[0168] In the above embodiment, a fan motor is exemplified as the rotating device, but the rotating device is not limited thereto. For example, the present invention may be applied to a dental handpiece or a spindle motor of a hard disk drive as the rotating device.

[0169] In addition, in the above-mentioned embodiments, all of the greases are thickened only by urea synthesized in the base oil, and no gelling agent is used.

[0170] Furthermore, components in the above-described embodiments may be appropriately replaced with well-known components without departing from the spirit of the present invention, and the above-described embodiments and modifications may be appropriately combined. Explanation of symbols

[0171] 1, 1A, 1B, 1C, 1D, 1E, 1F, 1G...Bearing 2...Rotating device 10...Inner ring (another raceway ring) 20...Outer ring (a raceway ring) 22...Protrusion 22a...End surface 22b...Inner peripheral surface (peripheral surface) 23...Outer ring raceway surface (raceway surface) 24, 24A, 24B, 24C, 24D, 24E, 124, 124E, 224, 224A, 224E...Concave portion 25, 25A, 25B, 25C...Edge portion 30...Rolling element 50... …Sealing component 51…Base portion 52…Extending portion 53…Plane portion 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 portion (raceway ring contact portion) 62, 162, 262, 462, 462A, 462B…Sealing component contact portion 227…Inclined portion.

Claims

1. A rolling bearing comprising: An inner ring and an outer ring, which are coaxially arranged with each other; A rolling element disposed between the inner ring and the outer ring; a sealing member mounted on the inner ring or the outer ring and covering a space between the inner ring and the outer ring from the outside in the axial direction; and grease, which is arranged between the rolling element and the sealing member, One of the inner ring and the outer ring has a circumferential surface facing the other raceway ring. On the peripheral surface, there are formed: a raceway surface that supports the rolling element in a rolling manner; and a recessed portion provided at a portion extending in the axial direction from an end edge in the axial direction of the raceway surface and recessed in the radial direction, The grease is in contact with the recessed portion, The unmixable consistency of the grease is greater than 178 and less than 287.

2. The rolling bearing according to claim 1, wherein: The grease contacts a portion of the recessed portion that faces a direction inclined outward in the axial direction with respect to the radial direction.

3. The rolling bearing according to claim 1 or claim 2, wherein: The recess has a portion facing a direction inclined toward the inside in the axial direction with respect to the radial direction.

4. The rolling bearing according to claim 1 or claim 2, wherein: The grease is in contact with the sealing member.

5. The rolling bearing according to claim 1 or claim 2, wherein: The grease contacts a ridge portion formed at an end edge of the recessed portion on the raceway surface side.

6. The rolling bearing according to claim 1 or claim 2, wherein: The one raceway ring has a protrusion protruding toward the other raceway ring and having the peripheral surface formed thereon, The protrusion has an end surface facing outward in the axial direction and connected to the peripheral surface at the peripheral edge on the other raceway ring side, The peripheral surface has a connecting surface formed between the recess and the end surface, The connection surface is further away from the other raceway ring in the radial direction than an end edge of the raceway surface in the axial direction.

7. The rolling bearing according to claim 1 or claim 2, wherein: The peripheral surface has an inclined portion extending from an end edge of the recessed portion on the raceway surface side toward the raceway surface at an inclination with respect to the radial direction and the axial direction.

8. The rolling bearing according to claim 7, wherein: The grease is arranged so as not to protrude from the inner side of the recessed portion toward the inclined portion in the radial direction.

9. The rolling bearing according to claim 1, wherein: The difference between the mixed consistency and the unmixed consistency of the grease is less than 50.

10. The rolling bearing according to claim 1, wherein: The ratio of the difference between the mixed consistency and the unmixed consistency of the grease to the mixed consistency was less than 22.7%.

11. The rolling bearing according to claim 1, claim 9 or claim 10, wherein: The unmixable consistency of the grease after 18 hours at 85°C was greater than 158.

12. A rotating device comprising: a rotating body configured to be rotatable; a support body that rotatably supports the rotating body; and The rolling bearing according to claim 1, which is interposed between the rotating body and the supporting body.

13. A method for manufacturing a rolling bearing, which is the following method for manufacturing a rolling bearing: have: An inner ring and an outer ring, which are coaxially arranged with each other; A rolling element disposed between the inner ring and the outer ring; a sealing member mounted on the inner ring or the outer ring and covering a space between the inner ring and the outer ring from the outside in the axial direction; and grease, which is arranged between the rolling element and the sealing member, One of the inner ring and the outer ring has a circumferential surface facing the other raceway ring. On the peripheral surface, there are formed: a raceway surface that supports the rolling element in a rolling manner; and The recessed portion is provided at a portion extending in the axial direction from the end edge of the raceway surface in the axial direction and is recessed in the radial direction. The manufacturing method of the rolling bearing: The method further comprises applying the grease to the recessed portion by bringing the grease into contact with the recessed portion. The unmixable consistency of the grease is greater than 178 and less than 287.

14. The method for manufacturing a rolling bearing according to claim 13, wherein: The sealing component has: an annular seat portion which contacts the one raceway ring from the outside in the axial direction; a protruding portion extending from a peripheral edge of the other raceway ring side of the inner ring and the outer ring of the seat portion toward the outside in the axial direction; and a flat portion extending in a radial direction from an end edge of the protruding portion on the outer side in the axial direction toward the other raceway ring, In the applying step, the grease is applied so as to protrude from the contact portion with the one raceway ring toward the outside in the axial direction and toward the other raceway ring. The method for manufacturing the rolling bearing further comprises: a contact step of bringing the sealing member close to the one raceway ring from the outside in the axial direction so that the flat surface portion contacts an outer edge of the grease in the axial direction; as well as An assembly process, after the contact process, brings the sealing component close to the one raceway ring, makes the seat portion contact the one raceway ring from the outside in the axial direction, and presses the grease inward in the axial direction by the flat surface portion.

Images