JP2002263994A - Rolling element for rolling bearing, method of manufacturing rolling element for rolling bearing, and rolling bearing - Google Patents

Abstract

(57) Abstract: A rolling element having at least one plane which has been subjected to high-precision processing and a true sphere made of steel balls are mixed and processed with high efficiency, and a rolling element having at least one plane can be easily and accurately formed. An object of the present invention is to provide a working method capable of working, and a rolling bearing incorporating a rolling element having at least one plane subjected to high-precision working. A true spherical body made of a steel ball and a spherical rolling element having an outer diameter serving as a rolling contact surface having a curvature in the axial direction and having at least one plane are provided at a predetermined interval from each other. The surfaces of the sphere 15 and the rolling element 6 are processed into a true sphere by mixing and processing between the two facing processing boards C1 and C2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling bearing capable of receiving a radial load, an axial load and a moment load in both directions, and relates to an industrial machine, a robot, a medical device, a food machine, a semiconductor / liquid crystal manufacturing device, an optical device and an optical device. Used for electronic devices.

[0002]

2. Description of the Related Art Rolling bearings have been proposed which are capable of receiving a radial load, an axial load in both directions, and a moment load with a single bearing which realizes a high moment rigidity and a low torque as well as an improvement in spin wear resistance (Japanese Patent Application). 2000
-16621). That is, the bearing configuration is such that a plurality of rolling elements are incorporated between a pair of races, and each race has a raceway groove having a raceway surface having a curvature larger than the radius of the rolling race, and at least one raceway groove. The race is composed of two raceways, and each of the rolling elements has an outer diameter serving as a rolling contact surface also having a curvature in the axial direction, has at least one plane or more, and alternately cross each other on the circumference. The rolling elements are arranged such that the outer diameters of the rolling elements are always in contact with each other at one point on each of the raceway surface of one raceway and the raceway surface of the other raceway.

[0003]

Here, the rolling element having at least one flat surface has a spherical surface formed into a true sphere. Therefore, as a method of forming the above-mentioned rolling element having a spherical surface formed into a true sphere, for example, a method of newly creating a flat surface by grinding and cutting a ball completely finished into a true sphere is adopted. It is also possible.

However, according to this, the following problems are considered. Since a considerable number of processings cannot be performed at one time, the cost increases, which is not practical. Further, as a problem that occurs simultaneously, the surface of the sphere may be damaged because the sphere is fixed at the time of processing. Furthermore, the connecting part (contact part) between the plane created by the additional processing and the rolling surface (spherical surface) becomes a sharp edge,
To alleviate this, a further post-processing step is required.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to provide a high-precision rolling element having at least one flat surface and a steel ball. A processing method capable of easily performing high-precision machining of a rolling element having at least one plane while mixing and processing a true sphere at a high efficiency, and a rolling element incorporating a rolling element having at least one plane subjected to high-precision processing. It is to provide bearings.

[0006]

In order to achieve the above-mentioned object, the present invention provides a technical solution which comprises a spherical surface having an outer diameter serving as a rolling contact surface having a curvature in the axial direction and having at least one flat surface. Rolling element, between the two processing board body facing each other at a predetermined interval, by mixing and processing a spherical rolling element having at least one plane or more with a true sphere made of steel balls, The surface of the rolling element is processed into a true spherical shape.

[0007] Further, a true spherical body made of a steel ball and a spherical rolling element having an outer diameter serving as a rolling contact surface having a curvature in the axial direction and having at least one plane are opposed to each other at a predetermined interval. A method of manufacturing a rolling element for a rolling bearing, in which the surfaces of the spherical body and the rolling element are processed into a true spherical shape by mixing and processing between the two processing boards.

[0008] A plurality of rolling elements are incorporated between a pair of bearing rings, each of which has a raceway groove having a raceway surface having a curvature larger than the radius of the rolling elements, and at least one of the raceways has two raceways. Each rolling element has an outer diameter serving as a rolling contact surface has a curvature also in the axial direction, has at least one plane or more, and is arranged alternately in an intersecting shape on the circumference. The outer diameters of the rolling elements are always in contact at one point each on the raceway surface of one raceway ring and the raceway surface of the other raceway that are opposite each other, and the rolling bodies are spaced apart from each other by a predetermined distance. A rolling bearing whose surface is processed into a true spherical shape is obtained by mixing and processing the two processing disk bodies facing each other together with a true sphere made of steel balls.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. Note that the present embodiment is merely an embodiment disclosed in the description of the present invention, and is not to be construed as limiting at all, and can be freely modified within the scope of the present invention.

FIG. 1 shows an embodiment of the rolling element of the present invention, in which a sphere is machined by the sphere machining apparatus shown in FIG.

The rolling element 6 is made of a steel material such as SUJ-2 (quenched and tempered product), and has an outer diameter 6a serving as a rolling contact surface having a curvature in the axial direction and a spherical shape having at least one plane 6b or more. The spherical surface (part other than the flat surface) 6e of the rolling element 6 is formed into a true spherical shape. 6c in the figure
Indicates a rotation center axis.

For example, the rolling element 6 has a structure in which upper and lower cut spheres having a pair of planes (relative surfaces) 6b, 6b (the upper and lower portions of the sphere are cut to form the relative surfaces 6b, 6b). The same applies to the following.), And then a spherical processing is performed on the spherical surface by a spherical processing device.

The upper and lower cutting widths of the rolling element 6 are not particularly limited, and the upper and lower cutting ratios may be equal or unequal, and can be arbitrarily selected within the scope of the present invention. That is, the relative surfaces 6b, 6b of the rolling elements 6
Both symmetric and asymmetric may be within the scope of the present invention.

FIG. 2 shows an embodiment of a rolling element in which two planes are asymmetric. The rolling element 6 of this embodiment is used particularly in the case of high-speed rotation. The rolling element 6 of the present embodiment has asymmetrical planes (relative surfaces) 6b and 6d, and the planes (relative surfaces) 6b and 6d.
By arranging the large end 6d of d to face the inner ring 2 of the bearing, the rotation of the rolling element 6 becomes more stable, and a lower torque can be realized.

Further, as shown in FIG. 3, the rolling element 6 may have a ball shape formed by cutting one of the upper and lower sides to form a plane.

Incidentally, the entire shape of the rolling element 6, the flat surfaces 6b, 6b
The presence / absence of (6d) and the magnitude of the curvature in the axial direction at the outer diameter 6a are not limited to the above specific shape at all, and can be arbitrarily changed within the scope of the present invention. That is, for example, in place of the relative surfaces 6b, 6b, non-parallel surfaces may be provided, and a rotation center axis 6c perpendicular to the both surfaces may be provided. The plane 6b and the spherical surface 6e
The connecting portion 6f with the (outer diameter 6a) may have an edge or a continuous smooth arc shape without the edge.

Next, one embodiment of a method for processing a spherical surface of the spherical surface of the rolling element 6 (a method for manufacturing a rolling element) will be described.

In the present embodiment, a rolling element (hereinafter simply referred to as a rolling element) 6 having a flat surface 6b is provided between two processing boards C1 and C2 opposed to each other with a predetermined space therebetween.
Is mixed with a true sphere (hereinafter, also simply referred to as a steel ball or sphere) 15 as a steel ball and processed (ground or ground) to process the spherical surface 6e of the rolling element 6 into a true sphere. I have. Further, according to the present embodiment, it is possible to efficiently mix the spherical surface of the steel balls 15 together with the rolling elements 6.

FIG. 4 is a diagram showing a configuration of a sphere processing device (lapping device) C for processing the rolling element 6 into a true spherical shape.
This is a configuration known as a sphere processing device. In the figure,
C1 and C2 are circular processing boards (lapping machines) facing each other at a predetermined interval. These two processing boards C1, C
Two concentric grooves C3 are formed on the surfaces facing each other. C4 is a disk-shaped conveyor rotatable at a fixed position and stores a large amount of rolling elements 6 and steel balls 15. With the rotation of the conveyor C4, the rolling elements 6 and the steel balls 15 on the conveyor C4 are sequentially fed between the two processing boards C1 and C2 in an aligned state.

Then, the rolling element 6 and the steel ball 15 are sandwiched between the two processing boards C1 and C2, and at least one of the processing boards C1 and C2 is pressed in the axial direction.
Alternatively, the rolling element 6 and the steel ball 1 are rotated by rotating C2.
The surface of No. 5 is processed into a true spherical shape. During this processing operation, the rolling elements 6 and the steel balls 15 are processed (polished or ground) while being guided by the grooves C3 of the both processing boards C1 and C2 while rolling.

At this time, it is already known that the fine removal speed of the surface of the sphere affects the finally obtained sphericity, and that the slower the processing, the higher the final accuracy. However,
Generally, it takes time to process a sphere, and it is not uncommon for the processing to be several days. When the processing speed is reduced, the processing time is further extended, and as a result, phenomena such as a change in processing pressure due to deformation of the lapping device due to a change in air temperature, lack of uniformity, etc. become remarkable. Degree was the limit.
Naturally, when only the rolling element 6 having a flat surface is thrown into the device C to be processed into a sphere, the value is less than that.

Therefore, in the present embodiment, the rolling elements 6
Is mixed with the steel balls 15 and processed (polished or ground), whereby the surfaces of the rolling elements 6 and the steel balls 15 are subjected to high-precision spherical processing.

In the case of this embodiment, when viewed from the rolling element 6 side, the processing load between the both processing boards C1 and C2 is the steel ball 15
And the working load distributed between the rolling elements 6 between the two working boards C1 and C2 is reduced.
Therefore, fine removal processing of the surface of the rolling element 6 is performed.

Further, since the steel ball 15 supports the processing load between the both processing boards C1 and C2 and restricts the relative position between the two processing boards C1 and C2, the steel balls 15 can be connected to both the processing boards C1 and C2. Even if there is some deformation of the sphere processing device that affects the distance,
Rolling element 6 with stable dimensions between both processing boards C1 and C2
Since fine removal of the surface can be accurately performed, adverse effects on the rolling elements 6 are reduced.

FIG. 6 is a graph showing the relationship between the mixing ratio of the steel ball 15 and the rolling element 6, the machining time, and the expected difference between the steel ball 15 and the rolling element 6 to be processed. The drawing conditions are as follows.

(A) Specific materials Steel ball, rolling element: SUJ-2 (hardened and tempered product), HRC
61-62 (b) Used grindstone diamond abrasive grain + metal bond (c) Average processing force per one sphere 200 gr / piece The processing speed depends on the mixing ratio of steel ball 15 and rolling element 6.
It becomes like the solid line in FIG. However, the finally obtained sphericity and the difference between the spheres to be machined are better as the amount of sphere surface removal each time the ball passes through both machining discs C1 and C2 is smaller. Since the amount does not become less than the removal amount, a tendency shown by a broken line in FIG. 6 is obtained. In FIG. 6, as an example, when the rolling elements are 100%, a sphere processing apparatus capable of processing the rolling elements having a difference of 300 nm between the spheres to be processed in 24 hours is assumed.

Therefore, taking into account the balance between the processing time and the required accuracy, the processing may be performed by changing the mixing ratio of the steel balls 15 and the rolling elements 6. In the case of 25%, the processing time takes 150 hours, but the difference between the spheres to be processed can be expected to be 90 nm or less.

As described in detail above, according to the method for processing a sphere according to the present embodiment, the mixing ratio of 1
Since the rolling elements 6 are mixed and processed (polishing or grinding), the processing is performed little by little, compared to the case of processing using only the rolling elements, and the processing is performed little by little. Processing can be performed. Further, according to the method of the present embodiment, the connecting portion 6f between the flat surface 6b and the spherical surface 6e (outer diameter 6a) can be formed into a continuous smooth arc shape without edges. Therefore, post-processing is not required.

In the lapping device C, which is a sphere processing device for carrying out the method of the present invention, it is necessary to maintain a constant processing load applied to each sphere to be processed in order to obtain high processing accuracy. Since it is effective to increase the number of balls between both processing boards, it is desirable to increase the lot. However, according to the method of processing a sphere according to the present embodiment, high-precision processing is possible even in a small lot. .

In the above-described embodiment, the mixing ratio of the rolling elements 6 to the steel balls 15 is 1/3, but the present invention is not limited to this, and the mixing ratio of the rolling elements 6 to the steel balls 15 is not limited to this. Can be appropriately selected in the range of 10% to 100%. Preferably, it is selected in the range of 10% to 95%, and more preferably, it is selected in the range of 10% to 75%.

Next, an embodiment of a rolling bearing incorporating the above-mentioned rolling element 6 will be described.

The rolling bearing has a plurality of rolling elements 6, 6,... Incorporated in a raceway groove 3 formed between an inner diameter of a raceway (outer ring) 1 and an outer diameter of a raceway ring (inner race) 2. Track ring 1,2
One or both of them are axially divided at an arbitrary position in the width direction in the axial direction, and are integrally assembled with bolts and rivets.

The raceway groove 3 is formed by raceway surfaces 4 and 5 having a radius larger than the radius of the rolling element 6. Further, in the present embodiment, the raceway surface 4 of the raceway ring (outer race) 1 is configured by two raceway surfaces 4a and 4b having a radius larger than the radius of the rolling element 6. As long as the shape of each raceway surface 4a, 4b has a shape suitable for rolling of the rolling element 6,
The cross section may be arbitrarily shaped such as an arch shape or a V-shape, and may be any shape such as a curved shape or a linear shape, and is not particularly limited. For example, a gothic arch is applied. In the embodiment, the grinding relief is formed at the intersection of the raceways 4a and 4b of the outer ring to facilitate the grinding process. However, a continuous elliptical raceway groove is formed without forming the grinding relief. It is also possible.

In the present embodiment, the race (outer ring) 1
Is composed of two raceway surfaces 4a and 4b having a radius larger than the radius of the rolling element 6. However, contrary to this embodiment, the raceway surface 5 of the raceway (inner race) 2 is It is good also as composition consisting of two raceway surfaces with a radius larger than the radius of rolling element 6, and both raceway surfaces 4 and 5 of raceway ring (outer ring) 1 and raceway ring (inner ring) 2 It is good also as composition consisting of two track surfaces of a radius larger than a radius. That is, the raceway surfaces 4 and 5 of at least one of the raceways (outer race) 1 and the raceway (inner race) 2 are in contact with the rolling elements 6.
The configuration is not particularly limited as long as the configuration is made up of two raceway surfaces having a radius larger than the radius. The above-mentioned grinding relief can be formed in the same manner as described above even when the race (ring) 2 is made up of two race surfaces.

The rolling elements 6 are configured as described above, and the rolling elements 6, 6...
The rotation center axes 6c perpendicular to 6b are alternately assembled in an intersecting manner so as to intersect with each other, and the outer diameter 6a of each rolling element 6 is always equal to the raceway surface 4 (4a, 4b) of one of the races 1.
And the raceway surface 5 (5a, 5b) of the other raceway ring 2 is in contact with each other at one point each.

The above-mentioned intersection state may be either orthogonal or non-orthogonal.

The method of arranging the rolling elements 6 in an intersecting manner is not particularly limited as long as the numbers are the same in both cases, that is, the rolling elements 6 may intersect one by one, If the number is the same in both cases even if they do not intersect, they may intersect two by two or intersect each other, such as one by one, and both are within the scope of the present invention.

The movement of each rolling element 6, 6 is guided by a cage 7 or a separator (spacer) 9.

The retainer 7 and the separator (spacer) 9
Pockets 8 for holding and guiding the rolling elements 6 or grooves 1
The shape is not particularly limited as long as it has a shape of 0 and 10, and can be arbitrarily selected and changed within the scope of the present invention. The guide system of the retainer 7 is not particularly limited, and may be inner ring guide, outer ring guide, or rolling element guide. Further, the configuration and shape of the retainer 7 are not particularly limited, and may be, for example, an integral type or formed from several parts.

For example, the retainer 7 is provided with pockets 8 on which the adjacent rolling elements 6, 6 can be alternately assembled so that the rotation center axes 6c, 6c are respectively crossed, on the circumference of the annular body. The rolling elements 6 are arranged at equal intervals and alternately in an intersecting manner with the same quantity as the quantity. Each pocket 8 ...
Are parallel to each other alternately and neither perpendicular nor parallel to the rotation axis of the bearing, and have a constant angle (inclined) at the same level as the contact angle of the rolling element 6.

Both axial sides 8a, 8 of each pocket 8.
The distance between b is slightly larger than the width of the rolling element 6. If the pocket 8 has slanted parallel side surfaces 8a and 8b, and the distance between the side surfaces 8a and 8b is formed to be slightly larger than the width of the rolling element 6, the pocket 8 may have the same shape. The overall shape is not particularly limited and can be changed within the scope of the present invention.

In the present embodiment, the rolling elements 6
... the same number of pockets 8 are arranged at equal intervals and alternately in an intersecting manner, but are not particularly limited. If both have the same number, they intersect by two or two by one. They may intersect like two, which is within the scope of the present invention.

Due to the influence of various factors, there is a possibility that spin or skew may occur in the rolling element during rotation. If the attitude of the rolling element cannot be controlled well, the rotational resistance of the bearing will increase or smooth rotation will occur. May not be possible. Therefore, according to the present embodiment, the pocket 8 of the cage 7 is provided with the parallel side surfaces 8a and 8b which are substantially the same as a fixed angle of the same level as the contact angle of the rolling element 6, and the pocket side surfaces 8a and 8b. This suppresses a change in the attitude of the rolling element 6 due to spin, skew, and the like of the rolling element 6, and can maintain the attitude of the bearing. Therefore, it is possible to reduce the torque of the bearing.

The separator 9 has a smaller diameter than the diameter of the rolling element 6, and has a concave shape for holding the adjacent rolling elements 6, 6 so that the rotation center shafts 6c, 6c cross each other as described above. The arc grooves 10 are formed in a cross shape with the relative surfaces 11. The radius of curvature of the arc groove 10 may be substantially the same as or larger than the radius of curvature of the rolling element outer diameter 6a, and is arbitrary. By using the separator 9 in this manner, the entire bearing can be made compact.

The state in which the preload is applied between the rolling element and the raceway surface is not particularly limited, that is, the preload may or may not be applied in the manufacturing stage, and both are within the scope of the present invention. .

As the material of the bearing rings 1 and 2 and the rolling elements 6 of these bearings, usually bearing steel is used. However, in order to improve the corrosion resistance and heat resistance according to the use environment, a corrosion-resistant coating,
Stainless steel, heat-resistant steel (for example, M50, etc.), ceramic, and the like are appropriately selected and are not particularly limited. Further, as a material of the retainer 7, an extruded retainer, a press retainer, a resin retainer, and the like are appropriately selected. For example, a metal such as brass or iron, or a polyamide 66 (nylon 66) is used.
-A synthetic resin such as polyphenylene sulfide (PPS) is selected within the scope of the present invention and is not particularly limited.

The internal clearance of the bearing is set to be small or negative as necessary. Thereby, higher moment rigidity of the bearing can be realized.

In the figure, reference numeral 14 denotes a sealing plate.
Corresponds to either a contact type seal or a non-contact type seal, or a non-contact type shield, and the shape is not particularly limited, and a well-known shape is appropriately selected within the scope of the present invention. . In the drawing, reference numeral 14a denotes a sealing surface of the sealing plate 14 which is in close contact with the inner bottom of the inner ring sealing groove and serves as a sealing surface.

The method of arranging the sealing plate 14 is not particularly limited, and may be arranged on both sides or on one side, if necessary, and both are within the scope of the present invention. Both the outer ring side and the inner ring side of the sealing surface are within the scope of the present invention. The shape of the seal, for example, the lip shape is not particularly limited, and even in line contact with the sealing surface, even in surface contact,
Either is within the scope of the present invention. Further, the presence or absence of the core metal is free, and the type having the core metal and the type without the core metal may be properly used as needed, and are not particularly limited. Also, the seal groove structure of the outer ring 1 and the inner ring 2 is not particularly limited, and can be appropriately changed within the scope of the present invention.
The presence or absence of the sealing plate 14 is not particularly limited, and it is within the scope of the present invention whether or not it is installed as necessary.

Therefore, according to the present embodiment, the outer diameter 6a of the rolling element 6 contacts the raceway surface 4a of the outer race 1 and the raceway surface 5 of the inner race 2 opposite each other at a total of two points (the contact points are 12, 12). 1
2), and the adjacent rolling element 6 is the raceway surface 4b of the outer race 1
And the raceway surface 5 of the inner ring 2 is brought into contact with each other at a total of two points one by one (contact points are indicated by 13 and 13).

Since the contact angles of the rolling elements 6, 6 intersect alternately, a single bearing can receive a radial load, an axial load and a moment load in both directions. The rolling element 6 is at one point on each of the raceway surfaces 4a and 5 and the other rolling element 6 is at one point on each of the raceway surfaces 4b and 5, and only two points (two points) are in point contact (12.12, 12). 13.13), large spin in the conventional four-point contact bearing can be eliminated.

Further, since the contact form between the rolling elements 6, 6 and the outer and inner races 1, 2 is the same as that of a general ball bearing, the rolling resistance is lower and a lower torque can be realized as compared with a cross roller.

[0053]

According to the present invention, since a true sphere made of steel balls and rolling elements are mixed and processed (polished or ground) at a predetermined mixing ratio in the above-described configuration, a considerable number of the spheres are formed at a time. The rolling element having at least one plane which can be machined and has been machined with high precision can be provided at low cost. Compared to the case of processing using only rolling elements, stable processing is performed little by little, and disturbance is hardly affected, so that high-precision processing can be performed.

In the lapping device, which is a sphere processing device for carrying out the present invention, it is necessary to maintain a constant processing load applied to one sphere to be processed in order to obtain high processing accuracy. According to the method for processing a sphere according to the above, high-precision processing is possible even in a small lot.

Further, according to the present invention, a flat surface is not newly created by additional processing, so that not only a significant cost reduction can be achieved but also the surface of the sphere is not damaged. Further, in the present invention, since the plane is formed at the elementary sphere stage, the connecting portion between the plane and the spherical surface is also formed round without an edge, so that a post-process is naturally unnecessary. Further, according to the production method of the present invention, a true sphere made of steel balls can be efficiently mixed and processed.

[Brief description of the drawings]

FIG. 1 is an enlarged perspective view showing an embodiment of a rolling element having two planes.

FIG. 2 is an enlarged perspective view showing another embodiment of a rolling element having two planes.

FIG. 3 is an enlarged perspective view of a rolling element having one plane.

FIG. 4 is a perspective view showing a configuration of a main part of a sphere processing device for performing a method of processing a rolling element.

FIG. 5 is a partially enlarged sectional view of both processing boards in the sphere processing apparatus shown in FIG. 4;

FIG. 6 is a view showing a relationship between a mixing ratio of a steel ball and a rolling element, a processing time, and an expected difference between the processed balls of the steel ball.

FIG. 7 is a sectional view showing an embodiment of a rolling bearing.

FIG. 8 is a perspective view showing one embodiment of a retainer.

FIG. 9 is a perspective view showing one embodiment of a separator.

[Explanation of symbols]

 1: outer ring 2: inner ring 3: raceway groove 6: rolling element 6a: outer diameter 6b: flat surface 6e: spherical surface

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) F16C 33/58 F16C 33/58 (72) Inventor Katsuhiro Yamazaki 12 Nippon Steel Ball Stock, Kirihara-cho, Fujisawa-shi, Kanagawa Association In-house F term (reference)

Claims (3)

[Claims] 1. A spherical rolling element having an outer diameter serving as a rolling contact surface having a curvature also in an axial direction and having at least one plane or more. In the meantime, by mixing and processing a spherical rolling element having at least one plane or more together with a true spherical body made of a steel ball, the spherical surface of the rolling element is processed into a true spherical shape. Moving body. 2. A sphere made of a steel ball and a spherical rolling element having an outer diameter serving as a rolling contact surface having a curvature in the axial direction and having at least one plane are opposed to each other at a predetermined interval. A method of manufacturing a rolling element for a rolling bearing, characterized in that the surfaces of the above-mentioned sphere and the rolling element are processed into a true spherical shape by mixing and processing between the two processing boards. 3. A plurality of rolling elements are incorporated between a pair of races, each of the races has a raceway groove having a raceway surface having a curvature larger than the radius of the raceway, and at least one raceway ring. Is composed of two raceway surfaces, and each of the rolling elements has an outer diameter serving as a rolling contact surface also having a curvature in the axial direction, has at least one plane or more, and is arranged alternately in an intersecting shape on the circumference. The rolling elements are always in contact with each other at one point on the raceway surface of one raceway and the raceway surface of the other raceway, the outer diameters of which are always opposed to each other. A rolling bearing characterized in that a spherical surface is machined into a true sphere by mixing and working with a true sphere made of a steel ball between two opposed machined bodies.