JP2020128787A - Retainer for rolling bearing, and rolling bearing - Google Patents

Abstract

To provide a retainer for a rolling bearing capable of reducing shear resistance of grease and reducing rotary torque of a rolling bearing, and to provide a rolling bearing having the retainer.SOLUTION: A retainer 1 is a crown retainer for a rolling bearing that is open to one axial side and has plural pockets 4 for holding balls as rolling elements on an annular retainer body 2. A retaining nib 3 projecting toward one axial side is formed on the retainer body 2. The retaining nib 3 is formed only in a partial place among plural places at both ends in a circumferential direction of each of the plural pockets 4. The plural pockets 4 are composed of a pocket 4A in which the retaining nib 3 is formed at both ends in a circumferential direction and a pocket 4B in which the retaining nib 3 is not formed at both ends in a circumferential direction, and the pocket 4A and the pocket 4B are disposed alternately in a circumferential direction.SELECTED DRAWING: Figure 1

Description

The present invention relates to a rolling bearing retainer, and a grease-lubricated rolling bearing having the retainer.

The rolling bearing is generally composed of an inner ring, an outer ring, rolling elements, and a cage. A seal member may be provided at the opening end in order to prevent foreign matter from entering from the outside or to prevent the lubricant enclosed in the inside from flowing out. Grease is often used as the lubricant inside the bearing. Grease is easy to handle and the design of the sealing device can be simplified. In addition, the grease does not need to be re-supplied and has excellent maintainability. However, in the case of grease lubrication with grease sealed in the bearing, the friction torque increases and the heat associated therewith increases due to the stirring resistance that the balls and the cage stir the grease and the shear resistance that shears the grease between the balls and the cage. It is known to occur. The following techniques have been conventionally proposed as techniques for reducing friction torque.

Non-Patent Document 1 discloses a technique for improving lubrication characteristics by changing a lubricant, and in a grease used inside a bearing of a hub unit bearing, the base oil kinematic viscosity of the grease is reduced to reduce the grease stirring resistance. I am trying.

Patent Document 1 describes a crown-shaped cage provided with a grease accommodating recess communicating with a pocket, in order to reduce the rotational torque of the bearing by changing the shape of the cage or the like. As a result, the grease is stored in the grease accommodating concave portion and rotates together with the cage, so that the torque is reduced.

In Patent Document 2, similarly, in order to reduce the rotational torque of the bearing by changing the shape of the cage, a crown-shaped cage in which the edge portion of the pocket is structured to scrape off the lubricant by line contact with the balls Is listed. The radius R of the conventional pocket-shaped cage made of resin is large relative to the balls to be held. Therefore, the balls are in contact with the central portion (pocket surface) in the radial direction of the cage. In that case, the grease adhering to the ball surface moves back and forth between the pocket surface and the ball surface during the bearing operation, and is in a state of being constantly stirred. On the other hand, in the cage of Patent Document 2, the radius R of the pocket in the radial direction is smaller than that of the ball to be held, and the ball and the edge portion of the pocket are brought into contact with each other to reduce the torque. By scraping the grease adhering to the ball surface at the edge of the cage pocket, the shear resistance of the grease is reduced and the rotational torque of the bearing is reduced.

JP, 2011-226635, A JP, 2012-31914, A

Hirokawa Ishikawa, "Technical Trends and Tribology of Hub Unit Bearings", Tribologist, 2009, Vol. 54, No. 9, p. 580-585

Non-Patent Document 1 improves lubrication characteristics by improving an encapsulated grease. However, for example, at a high temperature condition, the base oil kinematic viscosity is small and oil shortage easily occurs, so that the service life may be shortened.

In the cage having the grease accommodating concave portion as in Patent Document 1, for example, when the amount of grease filled is large, it becomes difficult to store the grease, and it may not be possible to expect lower torque. In addition, since the grease accommodating recess and the pocket communicate with each other, there is a concern that the pocket may be affected by shear resistance.

Further, the crown cage of Patent Document 2 focuses on the shear resistance of grease as a torque reduction, but when the grease supply amount becomes larger than the grease scraping amount, for example, when the grease filling amount is large. It may not be possible to expect a reduction in torque.

The present invention has been made in view of the above circumstances, and a rolling bearing retainer capable of reducing the shear resistance of grease and reducing the rotational torque of the rolling bearing, and a rolling bearing including this retainer. The purpose is to provide.

A cage for rolling bearing of the present invention is a cage for rolling bearings having a plurality of pockets, which are opened on one side in the axial direction and hold balls which are rolling elements, on an annular cage main body. , On the retainer main body, a holding claw protruding toward the one side in the axial direction is formed, and the holding claw is provided at a part of a plurality of positions at both circumferential ends of the plurality of pockets. It is characterized by being formed only.

The plurality of pockets includes a pocket A in which the holding claws are formed at both ends in the circumferential direction and a pocket B in which the holding claws are not formed in both ends in the circumferential direction. And are alternately arranged in the circumferential direction.

A flat portion serving as a rising reference surface of the holding claw is formed between the pocket A and the pocket B that are adjacent to each other in the circumferential direction, and the pocket depth of the pocket B from the reference surface is the ball. It is characterized by being smaller than the radius of.

The plurality of pockets are characterized in that the holding claw is composed of a pocket C formed only at one end in the circumferential direction.

The holding claw is curved toward one side in the circumferential direction and constitutes a part of the pocket. In the rolling bearing cage, the plurality of pockets C are such that the back surfaces of the holding claw are circumferentially arranged. It is characterized in that they are arranged so as to face each other.

An oil repellent layer is formed on the inner peripheral surface of at least one of the plurality of pockets.

At least one of the plurality of pockets has a cylindrical shape or a substantially quadrangular prism shape along the radial direction.

At least one of the plurality of pockets has a spherical shape having a predetermined radius of curvature, and the predetermined radius of curvature is smaller than the radius of the ball.

The rolling bearing of the present invention includes an inner ring and an outer ring, balls that are a plurality of rolling elements interposed between the inner ring and the outer ring, a retainer that holds the balls, and a grease that is sealed in a bearing inner space. A rolling bearing comprising: a cage, wherein the cage is a rolling bearing cage according to the present invention.

The rolling bearing retainer of the present invention has a retainer claw formed on the retainer main body so as to project to one side in the axial direction, and the retainer claw is at a plurality of positions at both circumferential ends of a plurality of pockets. It is formed only in some places, in other words, it has a structure in which the holding claws in a general crown type retainer are partly removed, so the area of the pocket surface becomes smaller, and between the pocket and the ball. The amount of grease to be sheared is reduced, and the rotation torque of the rolling bearing can be reduced.

The plurality of pockets is composed of a pocket A in which holding claws are formed at both ends in the circumferential direction and a pocket B in which holding claws are not formed in both ends in the circumferential direction, and the pockets A and B are arranged in the circumferential direction. Since they are arranged alternately, it is possible to prevent the cage from coming off from the rolling bearing, even though the retaining claws are partially removed. It is also possible to prevent the cage from tilting in the bearing.

Since the pocket depth of the pocket B from the reference surface is smaller than the radius of the ball, the area of the pocket B in contact with the ball is further reduced, and the shear resistance of the grease can be further reduced.

In addition, the plurality of pockets is composed of a pocket C in which the holding claw is formed only at one end in the circumferential direction, and the plurality of pockets C are arranged such that the back surfaces of the holding claw face each other in the circumferential direction. Therefore, it is possible to prevent the retainer from coming off from the rolling bearing, even though the holding claw is partially removed.

Since the oil-repellent layer is formed on the inner peripheral surface of at least one of the plurality of pockets, the grease existing between the ball surface and the inner peripheral surface of the pocket can be smoothly slid on the pocket surface. It is possible to preferably reduce the shear resistance of the.

Since at least one of the plurality of pockets has a cylindrical shape or a substantially quadrangular prism shape along the radial direction, the gap between the balls and the pocket (pocket gap) becomes larger than that in the case of the spherical shape, The shear resistance of grease can be reduced appropriately.

At least one of the plurality of pockets has a spherical shape having a predetermined radius of curvature, and since the predetermined radius of curvature is smaller than the radius of the ball, a ball is formed at the inner and outer diameter surface edge portions of the pocket. Contact. Therefore, the grease adhering to the ball surface can be scraped off at the edge portion, and the shear resistance of the grease between the pockets can be reduced.

Since the rolling bearing of the present invention includes the rolling bearing cage, the shear resistance of the grease is reduced, and the rotational torque of the rolling bearing can be reduced. Therefore, this rolling bearing can be suitably used even when the amount of grease filled is relatively large.

FIG. 1 is a perspective view of a rolling bearing cage according to a first embodiment of the present invention. FIG. 2 is a development view of the vicinity of adjacent pockets in FIG. 1. It is a development view of another example of FIG. It is a development view of another example of FIG. It is a perspective view of 2nd Embodiment of the cage for rolling bearings of this invention. FIG. 6 is a development view around the adjacent pockets in FIG. 5. It is a development view of another example of FIG. It is a development view of another example of FIG. It is a radial cross-sectional view (schematic diagram) of a cage. It is a partial cross section figure which shows an example of the rolling bearing of this invention. It is a development view of the adjacent pocket periphery in the conventional holder.

The rolling bearing cage of the present invention will be described with reference to FIG. FIG. 1 is a perspective view of a first embodiment of a cage according to the present invention. The cage 1 is a crown type cage and holds balls, which are rolling elements in the rolling bearing, at equal intervals in the circumferential direction. As shown in FIG. 1, the cage 1 has a plurality of pockets that are opened on one side in the axial direction and that hold balls that are rolling elements on an annular cage body 2. In addition, holding claws 3a and 3b are formed on the retainer body 2 so as to project to one side in the axial direction.

The cage of the present invention is designed to reduce torque by changing the pocket shape from the conventional general cage. Here, FIG. 11 shows a development view of the vicinity of adjacent pockets of the conventional crown-shaped cage. The conventional retainer 51 has a plurality of pockets 54 on a retainer main body 52, and has a pair of retaining claws 53a and 53b projecting in the axial direction at both circumferential ends of each pocket 54, respectively. The pair of holding claws 53a and 53b face each other in the circumferential direction and form a part of the pocket between them. Thus, in the conventional shape, a pair of holding claws 53a and 53b are provided in each pocket 54, and one ball is constrained by both claws.

On the other hand, the cage of the embodiment shown in FIG. 1 is provided with a pocket without both pawls (hereinafter, also referred to as a pocket without both pawls) for one ball and prevents the cage from coming off from the bearing. The pockets of the crown-shaped cage (hereinafter, also referred to as pockets with both claws) are mixed. Specifically, the plurality of pockets of the cage 1 are composed of a pocket 4A having holding claws formed at both ends in the circumferential direction and a pocket 4B having no holding claw formed at either end in the circumferential direction. A flat portion 5 serving as a rising reference surface of the holding claws 3a and 3b is formed between the pockets adjacent in the circumferential direction, and between the pockets 4A and 4B in FIG.

A pair of holding claws 3a and 3b facing each other are formed at both ends in the circumferential direction of the pocket 4A at a constant pitch in the circumferential direction, and the holding claws 3a and 3b facing each other are bent in a direction approaching each other. A pocket 4A is formed between the holding claws 3a and 3b. The pocket 4A is equivalent to the conventional pocket 54 (see FIG. 11). On the other hand, the holding claws are not provided at both ends in the circumferential direction of the pocket 4B, and the pocket 4B is formed as a recessed portion that is recessed from the flat portion 5 in the axial direction. By partially removing the holding claw, it is possible to reduce the grease shear resistance of the claw portion.

As shown in FIG. 1, in the cage 1, the pockets 4A and the pockets 4B are preferably arranged alternately in the circumferential direction. By arranging every other pocket 4A in which the holding claws 3a and 3b are formed at both ends in the circumferential direction, it is possible to prevent the cage from tilting or being displaced in the bearing, and stable rotation can be realized. Further, it is possible to prevent the cage from coming off the rolling bearing when the bearing rotates. Further, in the cage 1, it is preferable that the pocket 4B is provided so that the position of the pocket 4B is symmetrical with respect to the plane X passing through the central axis of the cage and extending along the axial direction.

In the cage of the present invention, it is preferable that an oil repellent layer (see FIG. 2) is formed on the inner peripheral surface of at least one of the plurality of pockets. FIG. 2 shows a development view of the vicinity of the adjacent pockets in FIG. In FIG. 2, the oil repellent layer 6 is provided on the inner peripheral surface of each of the pocket 4A and the pocket 4B. The oil repellent layer 6 only needs to have oil repellency, and a fluororesin layer, a coating film, or the like can be used.

Examples of the fluororesin used for the fluororesin layer include polytetrafluoroethylene (PTFE) resin, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA) resin, tetrafluoroethylene-hexafluoropropylene copolymer (FEP). Resin, tetrafluoroethylene-ethylene copolymer (ETFE) resin, polyvinylidene fluoride (PVDF) resin, polychlorotrifluoroethylene (PCTFE) resin, chlorotrifluoroethylene-ethylene copolymer (ECTFE) resin, etc. To be When the fluororesin layer is used as the oil repellent layer, only the pockets 4A and 4B can be formed into two layers as shown in FIG.

The coating film can be dried by immersing it in a solution diluted with an oil repellent, spraying a solution diluted with an oil repellent to a predetermined position and drying it, or sputtering a fluorine-based modified film. Can be mentioned. Examples of the oil repellent include silicone-based siloxanes, surfactants having a fluorine-based perfluoroalkyl group, fluorine-based silane coupling agents, and the like. Examples of commercially available products include MK guard and Neoseed NR manufactured by Nichika Chemical Co., Ltd., Unidyne manufactured by Daikin Industries, Ltd., and Asahi Guard E-SERIES manufactured by Asahi Glass Co., Ltd.

The layer thickness of the oil repellent layer is preferably 1 μm to 500 μm, more preferably 20 μm to 100 μm. The layer thickness can be, for example, in the above numerical range after firing, or can be formed so that the film thickness after firing is thicker than the above numerical range and can be set in the above range by mechanical processing such as polishing.

A bearing that is grease-lubricated by using the cage having the oil-repellent layer provides low torque. One factor in the torque of grease-lubricated bearings is the shear resistance of the grease interposed between the pocket and the ball. When oil repellency is imparted to the pocket surface, the grease present in the pocket gap slips on the pocket surface. Therefore, the grease shear resistance in the pocket gap is reduced, and a low torque can be obtained. This imparting of oil repellency can be applied without restricting the type of cage such as punching, chamfering, and resin molded cage.

The cage body of the present invention is made of a resin material or a metal material. As the resin material, any material can be used as long as it can be injection-molded and has sufficient heat resistance and mechanical strength as a cage material. It is preferable to use a resin material other than the above-mentioned fluororesin. For example, a polyamide resin such as a polyether ether ketone (PEEK) resin, a polyphenylene sulfide (PPS) resin, a thermoplastic polyimide resin, a polyamideimide resin, a nylon 66 resin, a nylon 46 resin, a nylon 6T resin, or a nylon 9T resin is used as a resin base material. In addition, a resin composition containing reinforcing fibers such as carbon fibers and glass fibers and other additives can be used.

Further, as the metal material, any material generally used as a cage can be used, and for example, cold rolled steel plate, carbon steel, etc. can be used. For example, it is obtained by press molding a metal plate.

In FIG. 2, the inner peripheral surfaces of the pockets 4A and 4B are spherical surfaces having a predetermined radius of curvature. The ball B is restrained in the axial direction, the circumferential direction, and the radial direction in the pocket 4A. On the other hand, the ball B is restrained in the circumferential direction and the radial direction in the pocket 4B, and is not restrained in the axial direction.

FIG. 3 shows a developed view of another example of FIG. In the example of FIG. 3, the cage 1 ′ is provided with both-clawless pockets (pockets 4</b>B) and the pocket depth H is smaller than a general pocket depth. The pocket depth H is the axial length from the reference surface of the flat portion 5 to the bottom of the pocket. The pocket height H of the cage 1 in FIG. 2 is larger than the radius r of the ball B (H>r), while the pocket height H of the cage 1′ in FIG. 3 is the radius r of the ball B. Is smaller than that (H<r). By reducing the pocket depth H, the area of the pocket that comes into contact with the balls is reduced, and the grease shear resistance can be further reduced. As the height of the reference surface becomes lower, the claw height of the holding claw becomes higher in the cage 1'of FIG. 3 than in the cage 1 of FIG.

FIG. 4 shows a developed view of another example of FIG. In the example of FIG. 4, the cage 1 ″ is provided with both-clawless pockets (pockets 4</b>B) and has a shape in which the pocket gap of the pockets 4</b>B is large. In FIG. 4, since the pocket 4B has a substantially quadrangular prism shape (a quadrangular prism shape with rounded corners) along the radial direction, the pocket gap becomes larger than that in the case of the spherical shape, and the shear resistance of grease is suitably reduced. it can. The shape in which the pocket gap is large is not limited to the configuration of FIG. 4, and may be, for example, a cylindrical shape along the radial direction. In the case of these pocket shapes, the ball B is restricted only in the circumferential direction.

The cage of the first embodiment described above is not limited to the examples of FIGS. 2 to 4, the oil repellent layer 6 is provided on the inner peripheral surfaces of the pocket 4A and the pocket 4B. However, for example, the oil repellent layer 6 may be provided only on the inner peripheral surface of the pocket 4A, or the inner peripheral surface of the pocket 4B. The oil repellent layer 6 may be provided only on.

FIG. 5: is a perspective view of 2nd Embodiment of the holder|retainer of this invention. The cage of the form shown in FIG. 5 employs a single-claw pocket as the pocket. Specifically, the plurality of pockets of the retainer 11 are configured by pockets 14C in which holding claws are formed only at one end in the circumferential direction. That is, the pocket 14C has a configuration in which one holding claw is removed from the pocket with both claws of the conventional crown type cage. By eliminating one holding claw, it is possible to reduce the grease shear resistance of the claw portion.

As shown in FIG. 5, the holding claws 13a and 13b are curved toward one side in the circumferential direction, and the inner peripheral surface thereof constitutes a part of the pocket. In the retainer 11, the plurality of pockets 14C are preferably arranged so that the back surfaces of the holding claws 13a and 13b face each other in the circumferential direction. In this case, the flat portions 15 on which the holding claws are not formed and the flat portions 15 on which the holding claws are formed are alternately formed in the circumferential direction. By disposing the pocket 14C as shown in FIG. 5, it is possible to preferably prevent the cage from coming off the rolling bearing during rotation of the bearing. The total number of pockets is not particularly limited, but is preferably an even number.

The arrangement of the pockets 14C is not limited to that shown in FIG. 5, and for example, the rear surfaces of the holding claws of all the pockets 14C may be arranged to face one side in the circumferential direction (clockwise direction or the like).

FIG. 6 shows a development view of the vicinity of the adjacent pockets in FIG. In FIG. 6, the oil repellent layer 16 is provided on the inner peripheral surface of each of the adjacent pockets 14C. In the present embodiment, the distance (dimension W) between the pocket end of the flat portion 15 and the root of the holding claw facing the pocket at the center position in the radial direction of the cage is set so that the ball B does not come off from the pocket 14C. , It must be smaller than the ball diameter R (W<R). This magnitude relationship is the same in FIGS. 7 and 8 described later.

FIG. 7 shows a developed view of another example of FIG. In the example of FIG. 7, a one-claw pocket (pocket 14C) is provided as a pocket and the pocket gap on one side in the circumferential direction of the pocket 14C is increased. In FIG. 7, in each pocket 14C, the pocket gap on the side opposite to the side on which the holding claw 13a is formed is large, and the pocket gap on the side opposite to the side on which the holding claw 13b is formed is large. .. As described above, the shear resistance of the grease can be reduced by increasing the pocket gap. Each pocket 14C in FIG. 7 has a recessed shape (a pocket shape excluding the holding claws) that is asymmetric with respect to the surface Y along the axial direction.

FIG. 8 shows a developed view of another example of FIG. In the example of FIG. 8, a one-claw pocket (pocket 14C) is provided as a pocket, and the pocket gaps on both sides in the circumferential direction of the pocket 14C are large. In FIG. 8, since the pocket 14C has a substantially quadrangular prism shape along the radial direction, the shear resistance of the grease can be reduced.

FIG. 9 shows a radial cross-sectional view of the pocket 4A in the cage 1 of FIG. As shown in FIGS. 9A and 9B, the inner peripheral surface of the pocket 4A has a spherical shape having a predetermined radius of curvature (pocket radius). In the configuration of FIG. 9B, the pocket radius of the cage 1 is larger than the radius of the ball B. That is, since the radius R of the pocket shape in the radial direction is larger than that of the held ball, the pocket surface comes into contact with the ball B. On the other hand, in the configuration of FIG. 9A, the pocket radius of the cage 1 is smaller than the radius of the ball B. That is, since the radius R of the pocket shape in the radial direction is smaller than that of the held ball, the edge B of the pocket 4A contacts the ball B. As shown in FIG. 9, the edge portion 7 is an edge portion located on the inner and outer diameter surfaces of the cage 1. In the configuration of FIG. 9A, the grease attached to the surface of the ball is scraped off by the edge portion 7, so that the grease shear resistance in the gap between the ball B and the pocket 4A can be reduced.

It is more preferable that the retainer of the present invention has a grease scraping structure (edge portion 7) as shown in FIG. Regarding the bearing torque, both the structure in which the holding claw is omitted and the grease scraping structure are focused on the grease shear resistance, and by combining these, the shear resistance can be further reduced.

An example of the rolling bearing of the present invention will be described based on FIG. FIG. 10 is a partial cross-sectional view of a deep groove ball bearing in which the crown cage of the present invention is incorporated as the rolling bearing of the present invention. As shown in FIG. 10, in the rolling bearing 21, an inner ring 22 having a raceway surface 22a on the outer peripheral surface and an outer race 23 having a raceway surface 23a on the inner peripheral surface are concentrically arranged. A plurality of balls 24, which are rolling elements, are arranged between the inner raceway surface 22a and the outer raceway surface 23a. The plurality of balls 24 are held in the pockets of the crown-shaped cage 25. The form of the cage 25 is as shown in FIGS. 1 and 5 (the cages 1 and 11). Further, the rolling bearing 21 is provided with an annular seal member 26 provided at both axial opening ends of the inner and outer rings, and is formed in a bearing inner space composed of the inner ring 22, the outer ring 23, the cage 25 and the seal member 26. It is lubricated by the enclosed grease 27.

The rolling bearing of the present invention is lubricated with grease. The grease is sealed in the bearing internal space and is intervened on the raceway surface or the like for lubrication. As the base oil constituting the grease, mineral oil, synthetic oil or the like can be used without particular limitation as long as it is usually used for rolling bearings. Further, as the thickener constituting the grease, any thickener commonly used for rolling bearings such as metallic soap and urea compounds can be used without particular limitation.

The amount of grease enclosed is not particularly limited as long as the desired lubrication characteristics can be secured, but it is preferably about 50% to 80% (volume ratio) of the static space volume in the bearing internal space. Here, the stationary space volume is the volume of the space in which the rolling elements and the cage do not pass during bearing rotation in the space volume of the inner ring, the outer ring and the seal member. Furthermore, by combining the configuration of FIG. 9(a), the grease on the ball surface is scraped off by the edge portion of the cage pocket, the stirring resistance of the grease can be reduced, and the grease filling amount is in the above range to prolong the service life. The rotation torque can be reduced while achieving the above.

The rolling bearing of the present invention is not limited to the form (deep groove ball bearing) of Fig. 10 as long as it is a type of bearing using a crown type cage. Further, it is possible to apply these rolling bearings with or without a seal member.

INDUSTRIAL APPLICABILITY The rolling bearing cage of the present invention can be widely used as a resin crown cage for rolling bearings in various applications, which can reduce the shearing resistance of grease and the rotational torque of rolling bearings.

1, 1', 1'' cage (roller bearing cage)
2 Cage main body 3a Holding claw 3b Holding claw 4A Pocket 4B Pocket 5 Flat part 6 Oil repellent layer 7 Edge part 11, 11', 11'' Cage (roller bearing cage)
12 Cage main body 13a Holding claw 13b Holding claw 14C Pocket 15 Flat part 16 Oil repellent layer 21 Rolling bearing 22 Inner ring 23 Outer ring 24 Ball (rolling element)
25 Cage 26 Sealing member 27 Grease

Claims (9)

A cage for a rolling bearing having a crown shape having a plurality of pockets for holding balls that are rolling elements and opening on one side in the axial direction on an annular cage body,
On the retainer main body, a retaining claw protruding to one side in the axial direction is formed,
The rolling bearing cage according to claim 1, wherein the holding claws are formed only at a part of a plurality of positions at both ends in the circumferential direction of the plurality of pockets. The plurality of pockets are composed of a pocket A in which the holding claws are formed at both ends in the circumferential direction and a pocket B in which the holding claws are not formed in both ends in the circumferential direction. The cage for a rolling bearing according to claim 1, wherein and are alternately arranged in the circumferential direction. A flat portion serving as a rising reference surface of the holding claw is formed between the pocket A and the pocket B that are adjacent to each other in the circumferential direction,
The cage for rolling bearing according to claim 2, wherein the pocket depth of the pocket B from the reference surface is smaller than the radius of the ball. The rolling bearing cage according to claim 1, wherein the plurality of pockets are pockets C in which the holding claws are formed only at one end in the circumferential direction. The holding claw is curved toward one side in the circumferential direction to form a part of the pocket,
The rolling bearing cage according to claim 4, wherein in the rolling bearing cage, the plurality of pockets C are arranged such that the back surfaces of the retaining claws face each other in the circumferential direction. The rolling bearing cage according to any one of claims 1 to 5, wherein an oil repellent layer is formed on an inner peripheral surface of at least one of the plurality of pockets. The rolling bearing according to any one of claims 1 to 6, wherein at least one of the plurality of pockets has a cylindrical shape or a substantially quadrangular prism shape along the radial direction. Cage. At least one of the plurality of pockets has a spherical shape having a predetermined radius of curvature, and the predetermined radius of curvature is smaller than the radius of the ball. The cage for rolling bearing according to any one of 7 to 7. A rolling bearing comprising an inner ring and an outer ring, balls which are a plurality of rolling elements interposed between the inner ring and the outer ring, a cage for holding the balls, and a grease filled in a bearing inner space. There
A rolling bearing characterized in that the cage is the cage for rolling bearings according to any one of claims 1 to 8.