JP2002227845A - Rolling bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling bearing capable of being used without generating seizure even under an environment which easily becomes a boundary lubrication. SOLUTION: A retainer 14 for retaining a ball 13 is provided between an inner ring 11 and an outer ring 12 of a ball bearing 10. This retainer 14 is formed by a heat-resistant resin such as PEEK and a DLC film 15 having a film thickness of approximately 0.5-10 μm is formed on an outer periphery surface thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to rolling bearings such as ball bearings and roller bearings.

[0002]

2. Description of the Related Art In a machine tool such as a machining center or a high-speed lathe, a rolling bearing such as a ball bearing or a roller bearing is used as a bearing for supporting a spindle. This type of rolling bearing has an inner ring that is externally fitted to a shaft to be supported, such as a spindle, and an outer ring that is provided on the outer periphery of the inner ring.When the inner ring relatively rotates integrally with the spindle, the inner ring and the outer ring are The rolling elements disposed between the rolling elements rotate while contacting the surfaces thereof with the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring, and the retainer holding the rolling elements rotates in the circumferential direction of the inner ring and the outer ring. It works.
Therefore, in such a rolling bearing, there is a possibility that frictional heat is generated at a contact portion between the inner and outer wheels and the rolling element to cause seizure. Therefore, grease lubrication or oil air filling the bearing with a lubricant such as grease is required. A small amount of oil lubrication is used to prevent seizure.

[0003]

However, in oil-air lubrication, when the bearing rotates at a high speed, an air curtain is generated inside the bearing, and this air curtain hinders the intrusion of the lubricant into the transfer surfaces of the inner and outer wheels. Grease lubrication is effective for lubrication of the bearing alone, but the grease agitation resistance is large and the heat generation of frictional heat is large under high-speed rotation conditions. There is a problem that is easily caused.

Further, when the spindle or the like is rotated at a high speed, there is a problem that the lubricant is scattered by centrifugal force and the boundary lubrication tends to be insufficient. In such a case,
The same problem occurs not only between the bearing raceway surface and the contact surface between the rolling elements, but also between the cage outer diameter surface and the outer ring inner diameter surface and between the cage inner diameter surface and the inner ring outer diameter surface. Therefore, an object of the present invention is to solve the above-mentioned problems and to provide a rolling bearing that can be suitably used without causing seizure or the like even in an environment where boundary lubrication tends to occur.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an inner ring fitted on a shaft to be supported, an outer ring provided on the outer periphery of the inner ring, and an inner peripheral surface of the outer ring. And a plurality of rolling elements that roll while contacting the outer peripheral surface of the inner ring with the surface, and a retainer that holds these rolling elements, wherein the outer peripheral surface of the retainer or the inner circumference of the outer ring is provided. A sliding resistance reducing film is formed on a surface and / or an inner peripheral surface of the cage or an outer peripheral surface of the inner ring.

With such a configuration, the sliding resistance (friction resistance) at the sliding portion between the outer ring and the cage and / or the sliding portion between the inner ring and the cage is reduced by the sliding resistance reducing film. Seizure can be prevented, and it can be suitably used without causing seizure even in an environment where boundary lubrication tends to occur. Here, the sliding resistance reducing film means a film that can reduce the sliding resistance of the sliding portion between the outer ring and the cage and / or the sliding portion between the inner ring and the cage, and specifically, for example, on the outer peripheral surface of the cage. This can be achieved by forming a hard carbon film (diamond-like carbon film) or a fluororesin coating film. In this case, the retainer is made of polyetheretherketone (PEEK, coefficient of linear expansion; 45 × 10 ⁻⁶ /
° C), polyphenylenesulfonoid (PPS, 28 × 1
0 ^-6 / ° C), thermoplastic polyimide resin, phenol resin, polyamide 66 (nylon, coefficient of linear expansion; 28 × 1)
0 ^-6 / ° C) or a light metal (for example, a magnesium alloy) having a specific gravity of 3 or less, and thus the retainer is made of a heat-resistant resin or a light metal or a titanium having a specific gravity of 3 or less. By using an alloy, the cage can be prevented from being thermally damaged due to frictional heat, as compared with, for example, a cage made of bearing steel, and a hard carbon film (hereinafter abbreviated as a DLC film) on the outer peripheral surface of the cage. ) Can be formed.

Further, by forming the retainer from a light metal such as a magnesium alloy, the weight of the retainer can be reduced as compared with the case where the retainer is formed from an iron or copper alloy, and the retainer has high strength. You can get a bowl. Further, as a material for forming the cage, a composite material including a heat-resistant resin such as PEEK and a reinforcing fiber such as glass fiber and carbon fiber may be used, and such a composite material is used as a material for forming the cage. Thereby, the mechanical strength of the cage can be increased. Further, when the DLC film is formed on the outer peripheral surface of the cage, Ti, S is formed between the outer peripheral surface of the cage and the DLC film.
An intermediate layer made of i or the like may be formed in advance, and by forming an intermediate layer made of Ti, Si, or the like between the outer peripheral surface of the cage and the DLC film in this manner, the outer peripheral surface of the cage can be formed. Thus, a DLC film can be favorably formed.

When the thickness of the DLC film is more than 10 μm, the internal stress of the DLC film increases and self-destruction occurs to reduce the sliding resistance reducing function. Because the surface is exposed and the sliding resistance reducing function is reduced, the thickness of the DLC film is 0.5
The range is preferably from 10 to 10 μm, and more preferably from 1 to 5 μm. Further, the thickness of the DLC film is preferably set to 1 to 3 μm from the viewpoint of controlling the film formation time and the gas pressure of the DLC film.

The thickness of the fluororesin coating film is 3
When the thickness is larger than 0 μm, unevenness of the film thickness easily occurs, and
When the thickness is smaller, the sliding resistance reduction effect is significantly reduced.
It is desirably in the range of 0 μm, preferably 5 to 20 μm.
In addition, as a method of forming a DLC film on the outer peripheral surface of the cage, plasma CVD (Chemical Vapor Deposition),
Nonequilibrium sputtering, vacuum arc discharge PVD
(Physical Vapor Deposition), an ion beam forming method, an ionization vapor deposition method, and the like can be used. The target is a carbon-based gas (acetylene, ethylene, methane, ethane, benzene, etc.) or graphite, and the DLC is applied to the outer peripheral surface of the holder. It is possible to form a film.

As a method of forming a fluororesin coating film on the outer peripheral surface of the cage, for example, the outer peripheral surface of the cage is subjected to a base treatment by applying shot peening or sebarrel, and then to a thermal treatment of polyamideimide or epoxy resin. A method of forming a coating layer composed of ethylene tetrafluoride and molybdenum disulfide using a curable resin as a binder on the outer peripheral surface of the retainer with a spray gun or the like, and firing the coating layer to form a fluororesin coating film. Can be used.

Further, molybdenum disulfide and ethylene tetrafluoride may be used alone. It is also beneficial to improve the seizure resistance by providing a metal solid lubricant layer of Ag, Sn, or the like after plating by plating or the like. Further, the synthetic resin used as the binder is not limited to polyamidimide, and other thermosetting resins such as epoxy resin can be used. Such a surface treatment by baking a solid lubricant or the like for reducing friction may be applied to at least one of the cage guide surfaces of the inner ring and the outer ring other than the cage.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing an embodiment in which the present invention is applied to a ball bearing. As shown in FIG. 1, a ball bearing 10 according to the present embodiment has an inner race 11 fitted externally to a shaft to be supported. An outer ring 12 provided on the outer periphery of the inner ring 11, a plurality of balls 13 which roll while contacting the inner peripheral surface of the outer ring 12 and the outer peripheral surface of the inner ring 11 with each other; And a retainer 14 that holds the outer ring 12 at equal intervals along the circumferential direction.

Of these components, the inner ring 11 and the outer ring 1
2 and the ball 13 are made of, for example, bearing steel (linear expansion coefficient;
2.5 × 10 ⁻⁶ / ° C.) and made of metal such as stainless steel (the ball 13 may be made of ceramics such as silicon nitride), but the retainer 14 is made of polyetheretherketone. (PEEK), polyphenylenesulfonoid (PPS), thermoplastic polyimide resin, phenol resin, nylon, and other heat-resistant resins.
The cage 14 has a sliding resistance reducing film DL on its outer peripheral surface.
It has a C film 15. The DLC film 15 is formed, for example, by plasma CVD (Chemical Vapor Deposition), non-equilibrium sputtering, or vacuum arc discharge PVD (Physical
It is formed on the outer peripheral surface of the holder 14 by a method such as vapor deposition, ion beam formation, or ionization vapor deposition, and has a thickness of 0.5 to 10 μm, preferably 1 to 5 μm.
m, more preferably 1-3 μm. Also,
The DLC film 15 has Hv 800-
It has a surface hardness of 3000 and a coefficient of friction of 0.2 or less.

The ball bearing 1 constructed as described above
The reference numeral 0 indicates that the DLC film 15 is formed on the outer peripheral surface of the retainer 14, so that the sliding at the sliding portion between the outer ring 12 and the retainer 14 is compared with the case where the DLC film 15 is not provided on the outer peripheral surface of the retainer 14. Since the dynamic resistance (friction resistance) is reduced, it can be suitably used without seizure even in an environment where boundary lubrication is likely to occur, and seizure resistance can be improved.

Further, since the cage 14 is formed of a heat-resistant resin such as PEEK or PPS, and has a specific gravity smaller than that of the cage 14 formed of, for example, bearing steel, the heat of the cage 14 due to centrifugal force is reduced. Damage can be prevented and the cage 14 can be prevented.
By forming a good DLC film 15 on the outer peripheral surface of
This effect is even greater. In the above-described embodiment, the DLC film 15 is formed on the outer peripheral surface of the retainer 14 to improve the seizure resistance. However, the same applies when the DLC film 15 is formed on the inner peripheral surface of the outer ring 12. Is obtained, and the DLC film 15 is formed on the inner peripheral surface of the retainer 14 or the inner ring 11.
By forming it also on the outer peripheral surface of, the seizure resistance can be further improved. Further, the portion where the DLC film 15 is formed is not limited to the outer peripheral surface of the cage 14, but may be formed on the end surface, the pocket, the inner peripheral surface, etc. of the cage 14.
A film 15 may be formed.

In the above-described embodiment, the cage 14 is formed of a heat-resistant resin such as PEEK or PPS. However, as a constituent material of the cage 14, a heat-resistant resin such as PEEK and a reinforcing fiber such as glass fiber or carbon fiber are used. The use of such a composite material as a constituent material of the cage 14 can increase the mechanical strength of the cage 14. Furthermore, the same effect as in the above-described embodiment can be obtained by forming the DLC film 15 on the outer peripheral surface of the cage 14 made of a light metal (for example, a magnesium alloy) having a specific gravity of 3 or less.

A DLC film 15 is formed on the outer peripheral surface of the cage 14.
May be formed between the outer peripheral surface of the cage 14 and the DLC film 15. As described above, T is set between the outer peripheral surface of the cage 14 and the DLC film 15.
By forming an intermediate layer made of i, Si, etc.,
The DLC film 15 can be favorably formed on the outer peripheral surface of the cage 14.

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 2 is a diagram showing an embodiment in which the present invention is applied to a roller bearing. As shown in FIG.
An inner ring 21 fitted externally to a shaft to be supported, an outer ring 22 provided on the outer periphery of the inner ring 21, and a plurality of rolling members rolling while contacting the inner peripheral surface of the outer ring 22 and the outer peripheral surface of the inner ring 21. Rollers 23 and a cage 24 for holding these rollers 23 at equal intervals along the circumferential direction of the inner ring 21 and the outer ring 22.
It is composed of

Of these components, the inner ring 21 and the outer ring 2
The roller 2 and the roller 23 are formed of, for example, a metal such as bearing steel or stainless steel (however, the roller 23 may be formed of a ceramic such as silicon nitride), but the retainer 24 has a specific gravity of 3 or less. It is formed of a light metal (for example, a magnesium alloy). The cage 24 has a fluororesin coating film 2 on its outer peripheral surface as a sliding resistance reducing film.
Five. The fluororesin coating film 25 is obtained, for example, by subjecting the outer peripheral surface of the retainer 24 to a base treatment such as shot peening, and then using a heat-resistant resin such as polyamideimide or epoxy resin as a binder.
A coating layer composed of FE) and molybdenum disulfide is formed on the outer peripheral surface of the retainer 24, and the coating layer is formed by heating at about 200 to 250 ° C., and has a thickness of 2 to 30 μm, preferably It is 5 to 20 μm.

The roller bearing 2 constructed as described above
In the case of No. 0, since the fluororesin coating film 25 is formed on the outer peripheral surface of the retainer 24, the outer ring 22
Resistance (friction resistance) at the sliding part between the shaft and the cage 24
Therefore, it can be suitably used without causing seizure even in an environment where boundary lubrication tends to occur, and seizure resistance can be improved.

Further, since the cage 24 is formed of a light metal having a specific gravity of 3 or less, the weight of the cage 24 is reduced as compared with the case where the cage 24 is formed of iron or a copper alloy, which is generated at the time of high-speed rotation. Centrifugal force can be reduced, and a cage having high strength can be obtained. In the above-described embodiment, the fluororesin coating film 25 is formed on the outer peripheral surface of the retainer 24 to improve the seizure resistance.
The same effect can be obtained even if the fluororesin coating film 25 is formed on the inner peripheral surface of the outer ring 22. Further, by forming the fluororesin coating film 25 on the inner peripheral surface of the retainer 24 or the outer peripheral surface of the inner ring 21, And seizure resistance can be further improved. Further, the portion where the fluororesin coating film 25 is formed is not limited to only the outer peripheral surface of the retainer 24, and the fluororesin coating film 25 is also formed on the end surface, the pocket, the inner peripheral surface, etc. of the retainer 24. Is also good.

In the above-described embodiment, the retainer 24 is made of a light metal having a specific gravity of 3 or less.
The cage 14 may be formed of a heat-resistant resin such as PPS.
Further, when the fluororesin coating film 25 is formed on the outer peripheral surface of the retainer 24, a metal solid lubricant layer such as Ag or Sn is plated between the outer peripheral surface of the retainer 24 and the fluororesin coating film 25 by a method such as plating. May be formed. By forming a metal solid lubricant layer of Ag, Sn or the like between the outer peripheral surface of the cage 24 and the fluororesin coating film 25 in this way, seizure resistance can be further improved.

In the ball bearing shown in FIG. 1, the seizure resistance when the sliding resistance reducing film such as the DLC film is formed on the outer peripheral surface of the cage 14 and when the sliding resistance reducing film is not formed is described. Using the test device of FIG.
Tables 1 and 2 show the results of tests on angular ball bearings having a diameter of 5 mm, an outer diameter of 120 mm, and a width of 23 mm. In addition,
Table 1 shows oil-air lubrication (0.08 cc / 12 min, spindle oil), constant pressure preload 147 N, rotation speed 15000
Table 2 shows the results of testing under the conditions of rpm, grease lubrication (Isoflex NBU15), constant pressure preload 196N,
The result of a test performed under the condition of a rotation speed of 12000 rpm is shown. In FIG. 3, reference numeral 31 denotes an angular contact ball bearing as a specimen, 32 denotes a rotating shaft, 33 denotes a pulley, and 34 denotes a thermocouple for temperature measurement.

[0024]

[Table 1]

[0025]

[Table 2]

In Tables 1 and 2, Example 1 is an example of a ball bearing in which a 1 μm-thick DLC film is formed on the outer peripheral surface of a cage 14 formed of polyetheretherketone. In order to increase the strength of the cage, 30% of carbon fibers are combined with the polyetheretherketone material. The necessary portion is the outer peripheral surface of the cage, but in this embodiment, since no masking was performed, DLC is also formed on the end surface, the pocket, and the inner peripheral surface. The formation of the DLC film
High vacuum arc discharge type P (Finland) manufactured by Daiark
Although a VD apparatus was used, the film formation method is not particularly limited. For example, a hot cathode plasma CVD apparatus using a pulse power supply capable of forming a DLC on an insulator can be used. The surface hardness measured by a microhardness tester at a pressing load of 20 mN was 2600 Hv in the example formed by a high vacuum arc discharge type PVD apparatus, but the hot cathode type plasma CVD was used.
Those using the device usually have a hardness of 2200 Hv.

In this embodiment, bearing steel is used for both the inner and outer rings and the rolling elements. However, stainless steel such as SUS440C may be used for the inner and outer rings, and ceramics such as silicon nitride may be used for the rolling elements. Example 2 is an example of a ball bearing in which a 3 μm-thick DLC film is formed on the outer peripheral surface of a cage 14 made of a magnesium alloy by using plasma CVD. An intermediate layer of about 0.4 μm of Ti and Si was formed by PVD, and methane gas was turned into plasma by an ion gun to perform chemical vapor deposition. Surface hardness by micro hardness tester is 21
00 Hv.

Embodiment 3 is an embodiment of a ball bearing in which a 10 μm-thick fluororesin coating film is formed on the outer peripheral surface of a cage 14 formed of polyetheretherketone. The surface of the polyetheretherketone retainer is previously roughened by shot peening, heated to 70 ° C, and uniformly rotated by a spray gun while rotating the retainer. Was formed on the outer peripheral surface of the cage, and heated at 220 ° C. for 1 hour to form a fired film having a thickness of 10 μm.

Embodiment 4 is an embodiment of a ball bearing in which a 15 μm-thick fluororesin coating film is formed on the outer peripheral surface of a cage 14 formed of a magnesium alloy.
The surface of the magnesium alloy cage was previously roughened by shot peening, heated to 70 ° C., and sprayed with a spray gun while uniformly rotating the cage.
After forming a coating layer on the outer peripheral surface of the cage by using TFE) with polyamideimide as a binder, the coating layer was subjected to 1.
Heating was performed for 5 hours to form a fired film having a thickness of 15 μm.

Comparative Example 1 is a conventional example of a ball bearing in which the retainer 14 is formed of polyetheretherketone, and Comparative Example 2 is a conventional example of a ball bearing in which the retainer 14 is formed of a magnesium alloy. As shown in Tables 1 and 2, when a sliding resistance reducing film such as a DLC film was formed on the outer peripheral surface of the cage 14 (Examples 1 to 4), the sliding resistance reducing film was not formed. The temperature of the outer ring 12 does not rise so much as compared with the case (Comparative Examples 1 and 2). In addition, the critical rotation speed leading to seizure was 10 times smaller than that of Comparative Examples 1 and 2.
About 20% higher. Therefore, by forming a sliding resistance reducing film such as a DLC film or a fluororesin coating film on the outer peripheral surface of the retainer 14, compared with a case where the sliding resistance reducing film is not formed on the outer peripheral surface of the retainer 14. As a result, the limit rotational speed of the bearing is increased, so that seizure resistance can be improved.

Next, in the roller bearing shown in FIG. 2, the name N1014 (inner diameter 70 mm, outer diameter 110 m
test using a cylindrical roller bearing (m, width 20 mm) with a sliding resistance reducing film such as a DLC film formed on the outer peripheral surface of the cage 24 and without the sliding resistance reducing film. The results obtained are shown in Tables 3 and 4. The test apparatus was modified from FIG. 3 so as to be able to cope with higher speeds. Table 3 shows oil-air lubrication (0.08 cc / 12 mi).
n, spindle oil), constant pressure preload 147N, rotation speed 25
Table 4 shows the results of a test performed under the conditions of 000 rpm, and Table 4 shows grease lubrication (Isoflex NBU15), constant pressure preload 19
It shows the result of a test under the conditions of 6N and a rotation speed of 15000 rpm.

[0032]

[Table 3]

[0033]

[Table 4]

In Tables 3 and 4, Example 5 is an example of a roller bearing in which a 1 μm-thick DLC film is formed on the outer peripheral surface of a cage 24 formed of polyetheretherketone, and Example 6 is a magnesium alloy. The embodiment of the roller bearing in which the DLC film having a thickness of 3 μm is formed on the outer peripheral surface of the retainer 24 formed by the method described in the above. In the seventh embodiment, the outer peripheral surface of the retainer 24 formed of the polyetheretherketone has the thickness of 10 μm.
Example 8 is an example of a roller bearing in which a 15 μm-thick fluororesin coating film is formed on the outer peripheral surface of a cage 24 formed of a magnesium alloy. . Comparative Example 3 is a conventional example of a roller bearing in which the cage 24 is formed of polyetheretherketone, and Comparative Example 4 is a conventional example of a roller bearing in which the cage 24 is formed of a magnesium alloy.

As shown in Tables 3 and 4, the cage 2
In the case where a sliding resistance reducing film such as a DLC film is formed on the outer peripheral surface of Example 4 (Examples 5 to 8), the outer ring 22 is formed as compared with the case where no sliding resistance reducing film is formed (Comparative Examples 3 and 4). Temperature does not rise so much. Also, the critical rotation speed leading to seizure is higher by about 10 to 20% than in Comparative Examples 3 and 4.
Therefore, by forming a sliding resistance reducing film such as a DLC film or a fluororesin coating film on the outer peripheral surface of the retainer 24, compared with a case where the sliding resistance reducing film is not formed on the outer peripheral surface of the retainer 24. As a result, the limit rotational speed of the bearing is increased, so that seizure resistance can be improved.

FIG. 4 is a diagram showing the relationship between the film thickness and the outer ring temperature rise by changing the thickness of the DLC film formed on the outer peripheral surface of the cage of Example 2 in Table 1; As shown in the above, when the thickness of the DLC film is larger than 10 μm, the internal stress of the film increases, self-destruction occurs, and the temperature of the outer ring rapidly rises. If the thickness of the DLC film is smaller than 0.5 μm, the metal surface is partially exposed, so that the function of reducing the sliding resistance of the DLC film under boundary lubrication conditions is reduced, and the temperature of the outer ring rapidly increases. . Therefore, the thickness of the DLC film formed on the outer peripheral surface of the cage is preferably 0.5 to 10 μm, and more preferably 1 to 5 μm, and from the viewpoint of controlling the film formation time and gas pressure, it is 1 to 3 μm. Is particularly preferred.

FIG. 5 is a diagram showing the relationship between the film thickness and the outer ring temperature rise by changing the thickness of the fluororesin coating film formed on the outer peripheral surface of the cage of Example 3 in Table 1. As shown in the figure, when the thickness of the fluororesin coating film is smaller than 2 μm, the function of reducing the sliding resistance is remarkably reduced, so that the temperature of the outer ring rapidly rises. Further, when the thickness of the fluororesin coating film is larger than 30 μm, the effect of improving the performance is small and unevenness of the film thickness is likely to occur. Therefore, the thickness of the fluororesin coating film formed on the outer peripheral surface of the cage is 2 to 30 μm.
m, preferably 5 to 20 μm.

[0038]

As described above, the rolling bearing according to the present invention has a sliding resistance reducing film on the outer peripheral surface of the cage or the inner peripheral surface of the outer ring and / or the inner peripheral surface of the cage or the outer peripheral surface of the inner ring. By reducing the sliding resistance in the sliding portion between the outer ring and the cage and / or the sliding portion between the inner ring and the cage, seizure due to frictional heat can be prevented, and even in an environment where boundary lubrication tends to occur. It can be suitably used without causing sticking or the like.

[Brief description of the drawings]

FIG. 1 is a view showing an embodiment in which the present invention is applied to a ball bearing.

FIG. 2 is a diagram showing an embodiment in which the present invention is applied to a roller bearing.

FIG. 3 is a view showing a test device used for a seizure test of a rolling bearing.

FIG. 4 is a diagram showing a relationship between a thickness of a DLC film formed on an outer peripheral surface of a cage and an outer ring temperature.

FIG. 5 is a diagram showing the relationship between the thickness of a fluororesin coating film formed on the outer peripheral surface of the cage and the outer ring temperature.

[Description of Signs] 10 Ball bearing 11 Inner ring 12 Outer ring 13 Ball 14 Cage 15 DLC film 20 Roller bearing 21 Inner ring 22 Outer ring 23 Roller 24 Cage 25 Fluororesin coating film

 ────────────────────────────────────────────────── ─── Continued on the front page F term (reference) 3J101 AA03 AA13 AA24 AA32 AA42 AA43 AA52 AA54 AA62 BA21 BA50 BA51 DA05 EA34 EA36 EA38 FA06 FA33 GA31 4K029 AA11 BA34 BC02 BD04 CA03 CA05 4K030 BA28 CA07 FA01 LA23

Claims (1)

[Claims] 1. An inner ring fitted externally to a shaft to be supported, an outer ring provided on an outer periphery of the inner ring, and a plurality of rollers rolling while bringing the inner peripheral surface of the outer ring into contact with the outer peripheral surface of the inner ring. A rolling bearing comprising a rolling element and a retainer for retaining the rolling element, wherein an outer peripheral surface of the retainer or an inner peripheral surface of the outer ring and / or
Or on the inner peripheral surface of the cage or the outer peripheral surface of the inner ring,
A rolling bearing characterized by forming a sliding resistance reducing film.