JP2011132999A - Rolling bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing device which secures a lubricating oil in an amount necessary for the guide surface of a cage, even when the supply of the lubricating oil is reduced. <P>SOLUTION: This rolling bearing device includes a rolling bearing 1 and nozzle members 3 which are installed adjacent to the outer ring 2 of the rolling bearing 1 and which injects a lubricant into the bearing space between the inner and outer rings 1, 2. An annular flange part 11 which is inserted into the bearing space and which has a nozzle hole 11a for the lubricant is provided to the nozzle member 3. The outer diameter surface of the flange part 11 serves as the guide surface 11b of the cage. The inner diameter surface 6a of the cage is guided by the cage guide surface 11b of the flange part 11. The cage guide surface 11b of the flange part 11 is formed into an irregular surface 25. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rolling bearing device capable of improving the lubricity of a cage guide surface such as a machine tool spindle bearing.

There are outer ring guide, inner ring guide, and rolling element guide methods as guide types for the cage of the rolling bearing. In the case where the rolling bearing is used for inner ring rotation, in the inner ring guide type cage, the lubricating oil is hardly held on the guide surface due to the centrifugal force of the inner ring rotation. Therefore, many rolling bearing cages that rotate at high speed have an outer ring guide system in which the outer diameter surface of the cage is guided by the shoulder of the outer ring. However, the guide clearance between the outer ring and the cage may decrease due to the centrifugal expansion and thermal expansion of the cage during bearing operation.
In order to avoid a decrease in the guide clearance, a method of guiding the cage inner surface with a lubricant supply nozzle has been proposed (Patent Document 1). In this method, the lubricating oil supplied from the nozzle passes through the cage guide surface and is smoothly discharged. Thereby, since the high-temperature lubricating oil does not stay on the guide surface, the lubricity of the guide portion is excellent.

JP 2009-74682 A

From the viewpoint of reducing rolling friction loss due to the agitation resistance and viscosity resistance of the lubricating oil, the amount of lubricating oil at the entrance of the elastohydrodynamic lubrication part should be reduced within the range where the solids do not contact each other. It is desirable to supply a small amount of lubricating oil. An increase in rolling friction loss leads to an increase in bearing temperature due to heat generation, leading to a reduction in machining accuracy in machine tool spindle applications.
On the other hand, since the cage guide surface becomes a sliding friction, it is necessary to supply and drain a sufficient amount of lubricating oil. Therefore, if the amount of oil supplied is reduced in order to reduce the rolling friction loss between the rolling elements and the races, it may not be possible to secure the amount of lubricating oil necessary for the cage guide surface.

  An object of the present invention is to provide a rolling bearing device capable of ensuring a necessary amount of lubricating oil for the cage guide surface even when the supply of lubricating oil is reduced.

The rolling bearing device according to the present invention includes a rolling bearing in which a plurality of rolling elements held by an annular cage are interposed between raceway surfaces of inner and outer rings, and a bearing between the inner and outer rings provided adjacent to the outer ring. In a rolling bearing device comprising a nozzle member for discharging a lubricant into a space, the nozzle member is provided with an annular flange portion having a nozzle hole for the lubricant inserted into the bearing space, and an outer diameter surface of the flange portion Is a cage guide surface that guides the inner diameter surface of the cage, and either one or both of the cage inner diameter surface and the cage guide surface of the flange portion is an uneven surface.
The uneven surface refers to a surface having fine unevenness enough to retain oil on the surface.

  According to this configuration, since the outer diameter surface of the collar portion of the nozzle member is used as a cage guide surface, the swinging of the cage increases, or the cage pocket holding the rolling element is damaged due to interference with the rolling element. Such a problem can be solved. In particular, since either one or both of the inner diameter surface of the cage and the cage guide surface of the flange portion is an uneven surface, the lubricating oil is easily retained, and even if a small amount of lubricating oil is present, the lubricating oil is applied to the uneven surface. Holds securely. Therefore, even when the amount of supplied oil is small or when the lubricating oil on the cage guide surface is reduced due to centrifugal force, the lubricating oil held on the concave and convex surfaces allows normal lubrication without causing contact between solids. Therefore, it is possible to reduce the amount of oil supplied from the conventional cage guide type to reduce the rolling friction loss between the rolling elements and the races, and to secure the necessary amount of lubricating oil on the cage guide surface. Can do. Since the amount of supplied oil can be reduced, heat generation due to the agitation resistance of the lubricating oil can be suppressed, and the temperature rise of the bearing can be suppressed.

The irregular surface may be a periodic structure having a fine structure formed by arranging at least a pitch determined in the circumferential direction. Lubricating oil is easily held in the recesses when the periodic structure has such a fine structure. Note that the periodic structure having a fine structure means a repetition period of 0.3 μm or more and 1.2 μm or less.
Each of the recesses may be a groove extending in a bearing axis direction or a direction inclined with respect to the bearing axis direction. In this case, pressure, that is, dynamic pressure, is generated in the lubricating oil existing in the cage guide clearance and the groove by the relative sliding movement between the cage inner diameter surface and the cage guide surface of the flange portion. Since the lubricating oil is smoothly guided along the groove by this dynamic pressure action, the lubricity over the entire circumference of the cage guide surface is further improved. In particular, when each recess is a groove extending in a direction inclined with respect to the bearing axis direction, the dynamic pressure can be generated more effectively by the above-described relative sliding motion. Accordingly, the lubricity of the cage guide surface can be further improved.

  The uneven surface may be a surface processed using a femtosecond laser. Either one or both of the inner diameter surface of the cage and the cage guide surface of the collar portion is irradiated with an ultrashort pulse laser beam called a femtosecond laser. Then, a finely processed surface having a depth of usually 0.1 μm or more and 1 μm or less is formed with a period according to the wavelength by the interference action of the laser light. Lubricating oil is reliably held on this finely processed surface.

  The uneven surface may be provided only on the cage guide surface of the flange. For example, for the purpose of irradiating the surface to be irradiated with laser light, a laser light source is arranged radially outward of the outer diameter surface of the collar, and laser light is emitted from this light source to the cage guide surface of the collar. It can be easily irradiated. In addition, the laser optical system can be simplified, and the equipment cost can be reduced.

  The cage may be made of laminated phenolic resin, polyamide, or PEEK, and the uneven surface may be provided on the inner diameter surface of the cage in the cage. The “PEEK” is an abbreviation for Polyether Ether Ketone. The speed of the bearing can be further increased by using this cage.

  The cage may be made of steel, a copper alloy, or a magnesium alloy, and the uneven surface may be provided on the inner diameter surface of the cage in the cage. It is desirable to apply a magnesium alloy from the viewpoint of strength and density.

Based on the sum of the maximum surface roughness of the inner diameter surface of the cage excluding the concave portion of the concave and convex surface and the maximum surface roughness of the cage guide surface of the flange portion excluding the concave portion, the bottom surface depth of the concave portion of the concave and convex surface May be defined.
When the oil film becomes less than the maximum surface roughness, solids contact with each other. Since the dynamic pressure groove is generally the same depth as the oil film thickness, the bottom surface depth of the concave portion of the uneven surface is the sum of the maximum surface roughness of the cage inner surface and the cage guide surface of the flange portion. And the same level. Thereby, the oil film thickness of the lubricating oil held in the recesses can be made thicker than the maximum surface roughness to prevent solids from contacting each other, and the lubricity of the cage guide surface can be improved more reliably.

The rolling bearing may be an angular ball bearing.
The rolling bearing may be a cylindrical roller bearing.
When the rolling bearing is an angular ball bearing or a cylindrical roller bearing, the lubricant discharged from the nozzle hole of the nozzle member may be air oil. In the case of this air oil, it is easy to perform a minute amount of lubrication.

  The rolling bearing device may be used for supporting the main shaft of the machine tool. In this case, it is possible to increase the speed of the spindle and reduce the temperature rise.

The rolling bearing device according to the present invention includes a rolling bearing in which a plurality of rolling elements held by an annular cage are interposed between raceway surfaces of inner and outer rings, and a bearing between the inner and outer rings provided adjacent to the outer ring. In a rolling bearing device comprising a nozzle member for discharging a lubricant into a space, the nozzle member is provided with an annular flange portion having a nozzle hole for the lubricant inserted into the bearing space, and an outer diameter surface of the flange portion Was used as a cage guide surface for guiding the inner diameter surface of the cage, and either one or both of the inner diameter surface of the cage and the cage guide surface of the flange portion was an uneven surface, thereby reducing the supply of lubricating oil. Even in this case, it is possible to secure the amount of lubricating oil necessary for the cage guide surface.
The concavo-convex surface is formed by arranging a plurality of concave portions at a pitch determined at least in the circumferential direction, and the concave surface is a fine periodic structure in which the bottom surface of each concave portion repeats the concave and convex portions along the bearing axis direction. Lubricating oil is easily held inside.
When each of the recesses is a groove extending in the bearing axis direction or in a direction inclined with respect to the bearing axis direction, the cage guide clearance and the cage by the relative sliding movement between the cage inner diameter surface and the cage guide surface of the flange portion. Pressure or dynamic pressure is generated in the lubricating oil present in the groove. Since the lubricating oil is smoothly guided along the groove by this dynamic pressure action, the lubricity over the entire circumference of the cage guide surface is further improved. In particular, when each recess is a groove extending in a direction inclined with respect to the bearing axis direction, the dynamic pressure can be generated more effectively by the above-described relative sliding motion. Accordingly, the lubricity of the cage guide surface can be further improved.

(A) is sectional drawing of the rolling bearing apparatus which concerns on one Embodiment of this invention, (B) is sectional drawing of the principal part of the rolling bearing apparatus. It is an enlarged plan view of the principal part of the rolling bearing device. It is an enlarged plan view of the principal part of the rolling bearing apparatus which concerns on other embodiment of this invention. It is principal part sectional drawing of the rolling bearing apparatus which concerns on other embodiment of this invention. It is principal part sectional drawing of the rolling bearing apparatus which concerns on other embodiment of this invention. It is an enlarged plan view of the principal part of the rolling bearing apparatus which concerns on further another embodiment of this invention. It is sectional drawing of the rolling bearing apparatus which concerns on other embodiment of this invention. It is sectional drawing of the high-speed spindle apparatus provided with the rolling bearing apparatus of embodiment of this invention.

An embodiment of the present invention will be described with reference to FIGS.
The rolling bearing device according to this embodiment is used as a main shaft bearing of a machine tool. The rolling bearing device includes a rolling bearing 1 and a nozzle member 3 provided adjacent to the outer ring 2 of the rolling bearing 1. The rolling bearing 1 includes an inner ring 4, an outer ring 2, a plurality of rolling elements 5 interposed between the raceway surfaces 4 a and 2 a of the inner and outer rings 4 and 2, and the rolling elements 5 held at regular intervals in the circumferential direction. And an annular cage 6. In this example, a cylindrical roller bearing is applied as the rolling bearing 1, and a cylindrical roller is applied as the rolling element 5. The cage 6 is made of, for example, a resin material such as laminated phenol resin, polyamide, PEEK, steel, copper alloy, magnesium alloy, or the like.

The inner ring 4 is fitted to the outer diameter surface of the main shaft (not shown). On the outer diameter surfaces of the inner ring 4 on both sides in the axial direction of the raceway surface 4a, sloped portions 4b having larger diameters from the inner ring end surface side toward the raceway surface 4a side are respectively provided.
The outer ring 2 is fixed in the bearing housing Hs. On both sides of the outer ring 2 in the axial direction, nozzle members 3 described later are arranged adjacent to the outer ring end face. The outer ring 2 is a hooked outer ring having hooks 7 on both sides of the raceway surface 2a. In the outer ring 2, on the inner diameter surface connected to the inner peripheral surfaces on both sides in the axial direction forming the flange 7, slope portions 2b having a larger diameter toward the outer ring end surface side are respectively provided. The outer ring 2 is formed with a through hole 8 and a groove 9 through which the lubricating oil staying on the raceway surface 2a is discharged out of the bearing. In the example of FIG. 1 (A), the through hole 8 extends radially outward from both corners between the raceway surface 2a and the flange surface 7a of the outer ring 2 and penetrates to the outer ring outer diameter surface 2c. These through-holes 8 are formed at regular intervals, for example, at a plurality of locations in the circumferential direction.

  The outer ring outer diameter surface 2c is formed with the groove 9 extending in the axial direction from the opening of each through hole 8 to the other side. That is, the groove 9 is formed in the outer ring 2 so as to extend to both side edges along the axial direction at a position that is in phase with the circumferential position where the through hole 8 is formed. An annular groove 10 that communicates with the groove 9 is formed in the bearing housing Hs, and the annular groove 10 communicates with an oil drain passage that is not shown. Therefore, the lubricating oil staying on the raceway surface 2a of the outer ring 2 can be discharged sequentially through the through hole 8, the groove 9, and the annular groove 10.

  The nozzle member 3 is made of, for example, bearing steel and is fixed in the bearing housing Hs. The nozzle member 3 discharges a lubricant into the bearing space between the inner and outer rings 1 and 2, and as this lubricant, air oil in which lubricating oil is mixed into the carrier air is used. The nozzle member 3 includes an annular flange 11 having an air oil nozzle hole 11 a inserted into the bearing space, and a nozzle member main body 12 provided integrally with the flange 11. The nozzle member main body 12 has a function as a spacer for positioning the axial position of the outer ring 2 and a function as an oil supply passage 13 for supplying air oil to the nozzle hole 11 a of the flange portion 11. The oil supply passage 13 opens from the outer diameter surface of the nozzle member main body 12 to a depth determined in the radial direction, and communicates with the nozzle hole 11 a of the flange portion 11. The nozzle holes 11 a are provided at a plurality of locations in the circumferential direction of the annular flange 11. Each nozzle hole 11a is inclined toward the inner diameter side toward the discharge-side tip. Air oil is discharged from the discharge-side tip of the nozzle hole 11a toward the vicinity of the end surface of the inner ring 4 on the inclined surface 4b.

  As shown in FIG. 1B, the outer diameter surface of the flange portion 11 is a cage guide surface 11b, and the cage inner diameter surface 6a is guided by the cage guide surface 11b of the flange portion 11. Further, the inner diameter surface 11c of the flange portion 11 of the nozzle member 3 forms a minute gap δ1 between the inner ring 4 and the inclined surface portion 4b along the corresponding inclined surface portion 4b.

  As shown in FIGS. 1B and 2, the entire portion of the outer diameter surface of the flange portion 11 facing the cage inner diameter surface 6 a is an uneven surface 25 having an uneven shape. The uneven surface 25 is a surface having fine unevenness to the extent that oil is held on the surface, and a plurality of grooves 14 that are recesses are formed side by side at a pitch determined in the circumferential direction indicated by an arrow L3 in FIG. Is done. Each groove 14 extends a predetermined distance L2 in the bearing axial direction represented by the arrow L1 in FIG. In FIG. 2, each groove 14 is represented by hatching. The bottom surface of each groove 14 is a periodic structure of a fine structure by microfabrication, that is, a fine periodic structure. As shown in FIG. 1B, a period in which irregularities of the order of wavelength (described later) are repeated along the bearing axis direction. Structure. The concavo-convex surface 25 including these grooves 14 is processed using, for example, an extremely short pulse laser called a femtosecond laser. The femtosecond laser is a kind of pulse laser that oscillates with a constant pulse width, and the pulse width is at a femtosecond level. One femtosecond is one thousandth of a second. The laser intensity of this femtosecond laser is obtained by dividing the pulse energy E by the value obtained by multiplying the area S of the beam spot by the time width t of the laser pulse (E / St).

  In this example, a laser light source (not shown) is disposed radially outward of the outer diameter surface of the flange portion 11, and the laser light of the femtosecond laser is disposed from the light source to the outer diameter surface of the flange portion 11. Is irradiated. Then, as shown in FIG. 1B and FIG. 2, a groove 14 composed of local irregularities 14a having a depth D1 of usually 0.1 μm or more and 1 μm or less at a period T according to the wavelength due to the interference action of laser light. Are self-organized along the axial direction. Within the range of the laser spot RS irradiated on the outer diameter surface of the flange 11, the above-mentioned interference action of the laser beam occurs, and a plurality of rows (5 rows in the example of FIG. 2) of grooves 14 are formed substantially simultaneously. . The groove width H1 and the groove interval H2 of the plurality of rows of grooves 14 are, for example, about several μm depending on the wavelength of the laser beam. After forming a plurality of rows of grooves 14 in this way, the flange portion 11 is relatively displaced about the axis with respect to the light source, and a plurality of rows of grooves 14 are formed within the range of the laser spot RS as described above. I will do it. The uneven surface 25 is formed by repeating this step over the entire outer diameter surface of the flange portion 11.

  When the oil film becomes less than the maximum surface roughness, solids contact with each other. Since the dynamic pressure groove is generally the same depth as the oil film thickness, the depth D1 of the groove 14 is the maximum surface roughness of the cage inner diameter surface 6a and the cage guide surface 6a of the flange portion 11. Same as the sum.

  According to the rolling bearing device described above, since the outer diameter surface of the flange portion 11 of the nozzle member 3 is the cage guide surface 11b, the whirling of the cage 6 is increased or the rolling element is caused by interference with the rolling element 5. The problem that the cage pocket Pt holding 5 is damaged can be solved. In particular, since the cage guide surface 11b of the flange portion 11 is the uneven surface 25, the lubricating oil is easily held, and the lubricating oil is reliably held on the uneven surface 25 even with a small amount of lubricating oil. Therefore, even when the amount of supplied oil is small or when the lubricating oil on the cage guide surface 11b decreases due to centrifugal force, the lubricating oil retained on the uneven surface 25 does not cause contact between solids and is normally lubricated. The

  Accordingly, the amount of oil supplied from the nozzle member 3 can be reduced as compared with the conventional cage guide type to reduce the rolling friction loss between the rolling elements 5 and the race rings 4 and 2, and the cage guide surface. The amount of lubricating oil required for 11b can be ensured. Since the amount of supplied oil can be reduced, heat generation due to the agitation resistance of the lubricating oil can be suppressed, and an increase in bearing temperature can be suppressed. Since the heat generation amount of the entire bearing is reduced, rotation at a higher speed is possible. Further, since the lubricant is air oil, it is easy to carry out a minute amount of lubrication. Since the lubricating oil staying on the raceway surface 2a of the outer ring 2 is sequentially discharged through the through hole 8, the groove 9, and the annular groove 10 during the bearing operation, the rolling friction loss can be more reliably reduced. it can.

  Since the groove 14 has a periodic structure in which the bottom surface of the groove 14 repeats local irregularities 14a along the bearing axis direction, and each groove 14 is a groove extending in the bearing axis direction, the retainer inner diameter surface 6a and the flange portion 11 are held. By the relative sliding movement with respect to the cage guide surface 11b, pressure is generated in the lubricating oil existing in the cage guide clearance δ2 and the groove 14, that is, dynamic pressure. Since the lubricating oil is smoothly guided along the groove 14 by this dynamic pressure action, the lubricity over the entire circumference of the cage guide surface 11b is further improved.

In the embodiment, the concave / convex surface 25 is formed using a femtosecond laser, but the concave / convex surface 25 may be formed by other processing methods.
As shown in FIG. 3, for example, a centrifugal flow barrel polishing method is used to form a plurality of round recesses 14A on the surface of the workpiece using a tip, followed by washing, and a surface finishing process is performed by a barrel polishing method. Small convexities on the surface may be removed or rounded. By processing the depth of the recess 14 </ b> A of the uneven surface 25 formed in this way to the same degree as the sum of the maximum surface roughnesses of the retainer inner diameter surface 6 a and the cage guide surface 11 b of the flange portion 11, the uneven surface 25. The lubricating oil held in the cylinder is normally lubricated without causing contact between solids.
Further, the uneven surface 25 may be formed by shot blasting, shot peening, etching, transfer from a mold, or the like. However, these methods require various adjustments according to the material of the workpiece because the workability varies depending on the material of the workpiece. On the other hand, when a femtosecond laser is used, processing is possible regardless of the material of the workpiece, and man-hours when changing the material of the workpiece can be reduced.

As shown in FIG. 4, an uneven surface 25 may be provided on the cage guide surface 11 b and the cage inner diameter surface 6 a of the flange portion 11. In this case, the lubricating oil held on both the concave and convex surfaces 25 does not cause solids to contact each other, and a structure having better lubricity than that of FIG. 1 can be obtained.
As shown in FIG. 5, the uneven surface 25 may be provided only on the inner diameter surface 6a of the cage. When the concave / convex surface 25 is provided on the inner diameter surface 6a of the cage, it is desirable to apply a magnesium alloy as the cage material from the viewpoint of strength and density.
As shown in FIG. 6, the groove 14 may be a groove extending in a direction inclined with respect to the bearing axial direction L1. During the operation of the bearing, the effect of the dynamic pressure generated in the groove 14 by the inclination angle α of each groove 14 is further increased, and the lubricity is further improved.

  As shown in FIG. 7, the rolling bearing 1 may be an angular ball bearing. In this case, the nozzle member 3 is disposed only on the outer ring rear side of the angular ball bearing, and is not disposed on the outer ring front side. In addition, air oil is discharged from the nozzle hole 11 a of the flange portion 11 of the nozzle member 3 toward the slope portion 4 b forming the counter bore portion of the inner ring 4. Other configurations and operational effects are the same as those in the examples of FIGS.

  FIG. 8 shows an example of a high-speed spindle device provided with the rolling bearing device of the embodiment. The spindle device SM is applied to a machine tool, and a tool or workpiece chuck is attached to the front side (machining side) end of the spindle 15. The main shaft 15 is supported on the front side in the axial direction by a pair of angular ball bearing type rolling bearing devices (FIG. 7), and on the rear side in the axial direction by a cylindrical roller bearing type rolling bearing device (FIG. 1A). Has been. The inner ring 4 of each rolling bearing 1 is fitted to the outer diameter surface of the main shaft 15, and the outer ring 2 is fitted to the inner diameter surface of the bearing housing Hs.

  As for the rolling bearing 1 on the front side of the main shaft, the inner ring 4 is fixed in the bearing housing Hs by the stepped surface 15a of the main shaft 15 and the outer ring 2 is fixed in the bearing housing Hs by the pressing lid 16A through the outer ring positioning spacer 17a. As for the rolling bearing 1, the inner ring 4 is fixed in the bearing box Hs by an inner ring positioning spacer 17b, and the outer ring 3 is fixed by a pressing lid 16B through the nozzle member 3. The bearing housing Hs has a double structure of an inner circumferential bearing housing HsA and an outer circumferential bearing housing HsB, and a cooling groove 18 is formed between the inner and outer bearing housings HsA and HsB. Nozzle members 3 are arranged on the other end face side of the outer ring 2 of the both rolling bearings 1, and an inner peripheral bearing box HsA is interposed between the nozzle members 3 and 3. A bearing fixing nut 19 that presses against the inner ring positioning spacer 17 and fixes the rolling bearing 1 is screwed to the rear end portion of the main shaft 15.

The holding lids 16A and 16B are provided with air oil introduction holes 21 for introducing air oil from air oil supply devices 20A and 20B, which are supply sources when the rolling bearing 1 is air-oil lubricated, respectively. It communicates with an air oil supply path 22 provided in the bearing housing HsA. In addition, the holding lids 16A and 16B are provided with oil drain holes 23, and these oil drain holes 23 communicate with an oil drain passage 24 provided in the inner peripheral bearing box HsA.
In the spindle device SM configured as described above, since the rolling bearing device is incorporated, the amount of oil to be supplied can be reduced to reduce the rolling friction loss between the rolling element 5 and the race rings 4 and 2, The amount of lubricating oil required for the cage guide surface can be ensured.

DESCRIPTION OF SYMBOLS 1 ... Rolling bearing 2 ... Outer ring 2a ... Raceway surface 3 ... Nozzle member 4 ... Inner ring 4a ... Raceway surface 5 ... Rolling body 6 ... Retainer 11 ... Gutter 11a ... Nozzle hole 11b ... Retainer guide surface 14 ... Groove 25 ... Unevenness surface

Claims (11)

A rolling bearing in which a plurality of rolling elements held by an annular cage are interposed between the raceway surfaces of the inner and outer rings, and a nozzle that is provided adjacent to the outer ring and discharges lubricant into a bearing space between the inner and outer rings. In a rolling bearing device comprising a member,
The nozzle member is provided with an annular flange portion inserted into the bearing space and having a nozzle hole for lubricant, and the outer diameter surface of the flange portion is used as a cage guide surface for guiding the inner diameter surface of the cage, and the holding A rolling bearing device characterized in that either one or both of the inner diameter surface of the cage and the cage guide surface of the flange portion are uneven surfaces.   2. The rolling bearing device according to claim 1, wherein the irregular surface is a fine periodic structure formed by arranging a plurality of the concave and convex surfaces at least at a pitch determined in a circumferential direction.   The rolling bearing device according to claim 2, wherein each of the recesses is a groove extending in a bearing axis direction or a direction inclined with respect to the bearing axis direction.   The rolling bearing device according to claim 1, wherein the uneven surface is a surface processed using a femtosecond laser.   The rolling bearing device according to any one of claims 1 to 4, wherein the uneven surface is provided only on the cage guide surface of the flange portion.   The rolling bearing device according to any one of claims 1 to 4, wherein the cage is made of laminated phenolic resin, polyamide, or PEEK, and the concave and convex surfaces are provided on the inner diameter surface of the cage in the cage.   5. The rolling bearing device according to claim 1, wherein the cage is made of steel, a copper alloy, or a magnesium alloy, and the concave / convex surface is provided on the inner diameter surface of the cage in the cage.   The rolling bearing device according to claim 1, wherein the rolling bearing is an angular ball bearing.   The rolling bearing device according to any one of claims 1 to 7, wherein the rolling bearing is a cylindrical roller bearing.   The rolling bearing device according to claim 8 or 9, wherein the lubricant discharged from the nozzle hole of the nozzle member is air oil. 11. The rolling bearing device according to claim 8, wherein the rolling bearing device is used for supporting a main shaft of a machine tool.

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