JP2008190630A - Retainer for radial ball bearings, and radial ball bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a retainer for a radial ball bearing, and a radial ball bearing to be able to reduce the vibration, noise and torque of the radial ball bearing. <P>SOLUTION: The retainer for the radial ball bearing has an axial cylindrical surface in the inside circumferential both side portion of a pocket 8. Center points O<SB>1</SB>, O<SB>2</SB>of each curvature of the axial cylindrical surfaces 18a, 18b are offset to the axial cylindrical surface opposite to each other from a center point O<SB>5</SB>of the ball on a rolling center axis α of a ball 5. Each curvature of a first axial cylindrical surface and a second axial cylindrical surface is restricted to 101 to 109% of the ball diameter. The diameter of the cylindrical portion comprising the first axial cylindrical surface and the second axial cylindrical surface is restricted to 101 to 106% of the ball diameter. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an improvement in a radial ball bearing used in various rotating machine devices and a cage constituting the radial ball bearing, and ensures sufficient lubrication of a sliding portion between the cage and the ball. The vibration and noise of the radial ball bearing are reduced by controlling the amount of circumferential movement and the amount of radial movement of the cylindrical surface.

Radial ball bearings as shown in FIG. 8 are widely used to support various rotating parts such as bearings of various rotating machinery devices.
In this radial ball bearing, an inner ring 2 having an inner ring raceway 1 on an outer peripheral surface and an outer ring 4 having an outer ring raceway 3 on an inner peripheral surface are disposed concentrically with each other, and a plurality of radial ring bearings are provided between the inner ring raceway 1 and the outer ring raceway 3. The balls 5 and 5 are provided so as to roll freely. In the case of the illustrated example, both the inner ring raceway 1 and the outer ring raceway 3 have a deep groove shape. The plurality of balls 5 and 5 are held in pockets 8 and 8 provided in the holder 6 so as to be freely rollable.

  The cage 6 constituting the radial ball bearing shown in FIG. 8 is called a corrugated press cage, each of which is obtained by press-molding a metal plate material, and is a pair of corrugated and annularly formed. It is formed by combining elements 9 and 9. Both the elements 9 and 9 are formed with recesses 8a and 8a for forming the pockets 8 and 8 at a plurality of positions in the circumferential direction. Then, the pair of elements 9 and 9 are brought into contact with each other at the portions removed from the recesses 8a and 8a, and these portions are coupled and fixed by a plurality of rivets 10 to form pockets 8 at a plurality of locations in an annular shape in the circumferential direction. , 8. The intermediate portion of the inner surface of each of the recesses 8a, 8a is a spherical holding concave surface 11 having a radius of curvature slightly larger than the radius of curvature of the outer surface of each of the balls 5, 5. Therefore, when the pair of elements 9 and 9 are brought into contact with each other, the recesses 8a and 8a are combined to form the pockets 8 and 8.

  Further, the cage 6a called a crown type cage shown in FIG. 9 rolls balls 5 and 5 (FIG. 8) at a plurality of circumferential positions of an annular main portion 7 made of synthetic resin or the like. Pockets 8 and 8 are provided for holding them freely. In the case of such a crown-shaped cage 6a, each of the pockets 8 and 8 includes one side surface of a pair of elastic pieces 12 and 12 arranged at a distance from each other on the main portion 7 and the main portion 7. 9 (vertical direction in FIG. 9) and one side (upper surface in FIG. 9) of spherical concave surfaces 13 and 13 provided between the pair of elastic pieces 12 and 12. The curvature radius of the concave surface portions 13 and 13 is slightly larger than the curvature radius of the outer surface of the ball 5.

  In the case of assembling a radial ball bearing, each of the balls 5, 5 is paired with the pair of elastic pieces 12, 12 constituting the pockets 8, 8 while elastically expanding the distance between the tip edges thereof. Between the elastic pieces 12 and 12. The cage 6a thus holds the balls 5 and 5 in the pockets 8 and 8 so that the balls 5 and 5 are connected to the inner ring track 1 and the outer ring track 3 (FIG. 8). In between, it is held freely rolling.

  When the radial ball bearing provided with the cage 6 or the cage 6a described above is used, relative rotation between the inner ring 2 and the outer ring 4 can be freely performed as the plurality of balls 5 and 5 roll. To do. At this time, the plurality of balls 5 and 5 revolve around the inner ring 2 while rotating. The cages 6 and 6 a rotate around the inner ring 2 at the same speed as the revolution speed of the balls 5 and 5.

  The portion between the outer peripheral surface of the inner ring 2 and the inner peripheral surface of the outer ring 4 is filled with or continuously supplied with a lubricant such as grease or other lubricating oil so that the relative rotation is performed smoothly. . Further, vibration and noise are prevented from occurring in the radial ball bearing, and failure such as seizure is prevented. In some ball bearings, both ends of the space between the outer peripheral surface of the inner ring 2 and the inner peripheral surface of the outer ring 4 are closed by a sealing member such as a seal plate or a shield plate, and the lubricant leaks from this space. In some cases, foreign matter such as dust is prevented from entering the space. However, FIG. 8 shows a ball bearing which does not have such a sealing member.

  In the case of a radial ball bearing incorporating the cages 6 and 6a as described above, even if a necessary amount of lubricant is filled or supplied, vibration is induced in the cages 6 and 6a. The built-in radial ball bearing may generate noise and vibration called cage noise. Such vibration of the cages 6 and 6a is caused by sliding friction between the balls 5 and 5 and the cages 6 and 6a due to a large amount of movement of the cages 6 and 6a with respect to the balls 5 and 5. Occurs based on. In order to suppress the generation of such cage noise, conventionally, the gap between the inner surfaces of the pockets 8 and 8 and the rolling surfaces of the balls 5 and 5 is reduced to reduce the cages 6 and 6a with respect to the balls 5 and 5. The amount of movement is reduced to suppress the generation of cage noise.

  However, if the amount of movement of the cages 6 and 6a relative to the balls 5 and 5 is simply reduced, cage noise is generated due to the shape of the inner peripheral surfaces of the pockets 8 and 8 of the cages 6 and 6a. This reason will be described with reference to FIGS. As shown in FIG. 10 and FIG. 11, sharp (large curvature) corners 15 and 15 exist in the opening peripheral portions 14 and 14 of the pockets 8 of the cages 6 and 6a. Provides resistance to lubricant flow.

  Accordingly, if the gap 16 between the inner surface of the pocket 8 and the rolling surface of the ball 5 is reduced to suppress the cage noise, the lubricant is less likely to flow into the gap 16. That is, the lubricant that tries to enter the gap 16 from the surrounding space as the ball 5 rolls is scraped off by the corners 15 and 15 and hardly enters the gap 16. For this reason, a sufficient amount of lubricant cannot be taken into the gap 16, and the frictional vibration at the sliding contact portion between the cages 6, 6 a and the balls 5, 5 can not be sufficiently suppressed, causing vibration and noise. To do.

  On the other hand, a cage in which the shape of the inner surface of the pocket is not a spherical surface but a radial cylindrical surface whose center axis is the radial axis of the cage is also known. In this way, in the case of a cage in which the inner peripheral surface of the pocket is a radial cylindrical surface, the lubricant adhering to the ball rolling surface is not scraped off at the opening edge of the pocket, and the cage and ball While frictional vibration at the sliding contact portion can be suppressed, excessive lubricant is taken into the pocket. When excessive lubricant is taken into the pocket, the resistance against the rolling of the ball in the pocket increases, and the rotational torque of the radial ball bearing incorporating the cage increases. When the radial ball bearing is, for example, a miniature bearing that is incorporated in the rotation support part of a small motor, the increase in rotational torque has a large effect on the performance of various devices incorporating the small motor (particularly battery life and wow flutter). Improvement is desired.

  Therefore, the present inventor first provided the radial ball bearing retainer disclosed in Patent Document 1 whose pocket inner surface shape is improved for the purpose of improving the cage sound performance and torque performance of the radial ball bearing, and We are trying to achieve the purpose.

  The technique disclosed in Patent Document 1 is a so-called crown-type cage, and the ball held in each pocket is transferred to a part of the inner surface of each pocket including the peripheral side opening edge. Axial cylindrical surfaces in the direction with the dynamic central axis as the central axis are provided on both sides in the circumferential direction at a part of these pockets. And the one end side part of the rolling center axis | shaft of the ball | bowl hold | maintained in the said pocket by the remainder of the inner surface of each of these pockets is made into the 1st spherical concave surface which has a curvature radius larger than the curvature radius of this ball rolling surface. Similarly, the other end portion is a second spherical concave surface having a radius of curvature larger than the radius of curvature of the rolling surface of the ball. Further, assuming that the ball is present in a neutral position in the pocket, the center point of curvature of the first spherical concave surface is shifted to the other end side from the center of the ball on the rolling center axis. The center of curvature of the second spherical concave surface exists at a position that is offset from the center of the ball toward one end on the rolling center axis.

By using the radial ball bearing cage disclosed in Patent Document 1, the following specific effects can be expected.
(1) The rotational torque (absolute value and fluctuation range) of a radial ball bearing incorporating a cage is prevented by preventing the presence of excessive lubricant between the ball rolling surface and the outer ring raceway and inner ring raceway. Reduction can be achieved.
(2) In addition, the lubricant that adheres to the part away from the running part and is not scraped off by the opening edge, improves the lubricity between the ball rolling surface and the pocket inner surface. This contributes to the prevention of the generation of vibration and noise called cage noise, and the improvement of the durability of radial ball bearings incorporating the cage.
(3) In particular, the first and second spherical concave surfaces are provided on the remaining part of the inner surface of the pocket, and the center points of the curvatures of both spherical concave surfaces are shifted in an appropriate direction with respect to the center of the ball. Optimum incorporation of the lubricant into the pocket while preventing the displacement of the cage in the axial direction by making the minimum value of the distance between the spherical concave surface and the axial cylindrical surface and the rolling surface of the ball substantially coincide. Can be done.

  Further, in the prior art disclosed in Patent Document 1, a configuration in which the distance between the opening edge of the axial cylindrical surface and the rolling surface of the ball is different between the outer diameter side and the inner diameter side of the cage is also adopted. Adjusting the scraping effect of the lubricant at the opening edge of each axial cylindrical surface, adjusting the amount of lubricant fed into the pocket, reducing the cage noise and reducing the radial ball bearing torque It is intended to

  In the prior art disclosed in Patent Document 1, the present inventor finds useful features that exhibit various unique functions and effects as described above. However, the present inventor has found the following room for improvement and is more preferable for a radial ball bearing. Further improvements have been made for the purpose of providing a cage and a radial ball bearing.

That is, in the prior art disclosed in Patent Document 1, since the central axis of the axial cylindrical surface in the circumferential direction of the cage pocket coincides with the central axis of the ball, depending on the curvature of the axial cylindrical surface,
(1) Axial cylindrical surface and the amount of movement of the ball in the circumferential direction
(2) Radial movement of cage
(3) It is difficult to independently control the amount of grease taken in by the inner and outer edges of the axial cylindrical surface of the cage pocket, and it may be difficult to individually reduce radial ball bearings to vibration, noise, and torque.
In addition, in order to suppress the cage noise generated during the operation of the radial ball bearing and to reduce the dynamic friction torque acting on the radial ball bearing, the clearance between the axial cylindrical surface of the cage and the ball is simply reduced. Instead, it is necessary to regulate to an appropriate gap size.
Japanese Patent No. 3744663

  An object of the present invention is to provide a radial ball bearing retainer and a radial ball bearing capable of reducing vibration, noise and torque of the radial ball bearing.

In order to achieve the above object, a first aspect of the present invention is a radial ball bearing in which a plurality of balls are formed in an annular shape and pockets are provided at a plurality of locations in the circumferential direction so as to be able to roll freely. For cages,
The first axial cylindrical surface having a radius of curvature larger than the radius of curvature of the rolling surface of the ball, the one end side portion of the portion including the peripheral surface side opening edge of the cage in a part of the inner surface of each pocket,
Similarly, the other end side portion is a second axial cylindrical surface having a radius of curvature larger than the radius of curvature of the rolling surface of the ball,
Assuming that the ball is in a neutral position in the pocket,
The center point of curvature of the first axial cylindrical surface is present at a position on the rolling center axis of the ball that is offset from the center of the ball toward the axial cylindrical surface on the other end side,
One of these pockets is located so that the center point of curvature of the second axial cylindrical surface is located on the rolling center axis of the ball at a position closer to the axial cylindrical surface on one end side than the center of the ball. Is provided on both sides in the circumferential direction,
The curvature of each of the first axial cylindrical surface and the second axial cylindrical surface is regulated to 101 to 109% of the ball diameter, and the first axial cylindrical surface and the second axial cylindrical surface are The diameter of the configured cylindrical part is regulated to 101 to 106% of the ball diameter,
The one end side portion of the rolling center axis of the ball held in the pocket at the remaining part of the inner surface of each pocket is a first spherical concave surface having a radius of curvature larger than the radius of curvature of the rolling surface of the ball,
Similarly, the other end side portion is a second spherical concave surface having a radius of curvature larger than the radius of curvature of the rolling surface of the ball,
Assuming that the ball is present in a neutral position in the pocket, the center point of curvature of the first spherical concave surface is shifted to the other end side from the center of the ball on the rolling center axis of the ball. Exists in position,
A radial ball bearing retainer characterized in that a center point of curvature of the second spherical concave surface is present at a position offset toward one end side from the center of the ball on the rolling center axis of the ball. That is.

In the second invention, an inner ring having an inner ring raceway on an outer peripheral surface and an outer ring having an outer ring raceway on an inner peripheral surface are arranged concentrically with each other, and the radial ball of the first invention is interposed between the inner ring raceway and the outer ring raceway. A plurality of balls, which are rotatably held in a plurality of pockets provided in the bearing cage, are provided to freely roll,
A radial characterized in that the pitch circle diameter of each pocket is different from the diameter of the pitch circle of each ball, and the pitch circle of each pocket is located outside or inside the pitch circle of each ball. This is a ball bearing.

  According to the present invention, it is possible to provide a radial ball bearing retainer and a radial ball bearing that can reduce vibration, noise, and torque of the radial ball bearing.

  Hereinafter, an embodiment of the present invention will be described.

  1 to 5 show a first embodiment of the present invention. In this embodiment, the present invention is applied to the crown type cage shown in FIG. The present invention relates to a radial ball bearing retainer having axial cylindrical surfaces on both sides in the circumferential direction of the inner surface of a pocket, and the center point of each curvature of the axial cylindrical surface is set on the rolling center axis of the ball. The point of the first axial cylindrical surface and the second axial cylindrical surface that are located near the opposite axial cylindrical surfaces from the center and the curvature of each of the first axial cylindrical surface and the second axial cylindrical surface are set to be 101 to 109% of the ball diameter. It is characterized in that it is regulated and the diameter of the cylindrical portion constituted by the first axial cylindrical surface and the second axial cylindrical surface is regulated to 101 to 106% of the ball diameter. The effect is the same as that of Patent Document 1 described above. Hereinafter, the characteristic parts of the present invention will be described together with the main components of Patent Document 1.

In the cage of the present embodiment, the inner surface of the pocket 8 provided on one axial surface of the annular main portion 7 is provided with a first spherical concave surface 17 at the center in the circumferential direction.
The first spherical concave surface 17 has a curvature radius R17 that is slightly larger than the curvature radius R5 of the rolling surface of the ball 5 held in the pocket 8 (see FIG. 3).
Then, on both sides in the circumferential direction of the first spherical concave surface 17, one end side portion of the portion including the circumferential surface side opening edge of the cage at a part of the pocket inner surface is from the radius of curvature of the rolling surface of the ball 5. A first axial cylindrical surface 18a having a slightly larger radius of curvature R18a, and a second axial cylindrical surface having a radius of curvature R18b slightly larger than the radius of curvature of the rolling surface of the ball 5 at the other end. 18b (in this embodiment, the right side in FIG. 2 is the first axial cylindrical surface 18a and the left side in FIG. 2 is the second axial cylindrical surface 18b). These first axial cylindrical surface 18a, One end of the second axial cylindrical surface 18 b is formed in a state of being continuous from both circumferential ends of the first spherical concave surface 17.

  The first axial cylindrical surface 18a and the second axial cylindrical surface 18b are formed on the assumption that the ball 5 held in the pocket 8 is in a neutral position in the pocket 8, and the first axial cylindrical surface 18a. The center point O1 of the curvature of the ball 5 exists on the rolling center axis α of the ball 5 at a position offset toward the axial cylindrical surface 18b on the other end side from the center O5 of the ball 5, and the second axial cylinder. Each of the pockets 8 is such that the center point O2 of the curvature of the surface 18b is located near the axial cylindrical surface 18a on the one end side with respect to the center O5 of the ball 5 on the rolling center axis α of the ball 5. Is provided on both sides in the circumferential direction.

  In the present embodiment, the curvature of each of the first axial cylindrical surface 18a and the second axial cylindrical surface 18b is 101 to 109% of the ball diameter, and the first axial cylindrical surface 18a and the first axial cylindrical surface 18b The diameter D1 of the cylindrical portion constituted by the second axial cylindrical surface 18b is regulated to be 101 to 106% of the ball diameter.

  That is, the ball 5 held in the pocket 8 with the relative rotation of the inner ring 2 and the outer ring 4 (FIG. 8) constituting the ball bearing has a rolling center axis α parallel to the center axis of the main portion 7. Roll to the center. Each pair of the first axial cylindrical surface 18a and the second axial cylindrical surface 18b provided for each of the pockets 8 is positioned on a single cylindrical surface of the rolling center axis α.

The axial cylindrical surface 18X indicated by a broken line in FIG. 2 is a cage (hereinafter referred to as the following patent document 1) in which the center point of each curvature coincides with the center O5 of the ball on the rolling center axis α of the ball 5. This is called a conventional cage.) It is an axial cylindrical surface in the pocket 8.
In this way, the center points O1 and O2 of the respective curvatures are present on the rolling center axis α of the ball 5 at positions offset toward the axial cylindrical surfaces facing each other than the center O5 of the ball 5. Therefore, the radius of curvature of each of the axial cylindrical surfaces 18a and 18b can be set larger than that of the conventional cage described above.

Therefore, for example, when the radial movement amount is set to be the same as that of the conventional cage, the inner diameter edge E1 (or outer diameter edge E2) of the first axial cylindrical surface 18a and the second axial cylindrical surface 18b is held in the conventional manner. If the same setting as that of the cage is used, the amount of movement in the radial direction of the cage is equivalent, and the circumferential clearance S1 can be made smaller than the conventional circumferential clearance S10.
As a result, the amount of grease taken into the pocket 8 is equivalent to that of the conventional cage, and the amount of movement in the circumferential direction can be suppressed, and the effect of suppressing vibration and noise such as cage noise is improved. Further, the curvature of each of the first axial cylindrical surface 18a and the second axial cylindrical surface 18b is set to be 101 to 109% of the ball diameter, and the first axial cylindrical surface 18a and the second axial cylindrical surface. Since the diameter D1 of the cylindrical portion constituted by the surface 18b is regulated to be 101 to 106% of the ball diameter, the suppression of abnormal vibration such as cage noise and the torque performance are good.

  Further, as shown in FIG. 1 and FIG. 3, of the pair of elastic pieces 12, 12 provided at the opening portions at both ends of the pocket 8, the inner peripheral surface constituting the pocket 8 is respectively the rolling center. On the axis α, the second spherical concave surfaces 19 and 19 are centered on a different point from the central point of the first spherical concave surface 17. The second spherical concave surfaces 19 and 19 are formed so that the traveling portion of the ball 5 held in the pocket 8 does not come off from the pair of axial cylindrical surfaces 18a and 18b. , 18b to regulate the length and shape thereof. For this purpose, the first spherical concave surface 17 and the second spherical concave surfaces 19, 19 are positioned at the rolling center axis α with a radius of curvature larger than the radius of curvature of the rolling surface of the ball 5. Let

The first spherical concave surface 17 and the second spherical concave surfaces 19, 19 are mutually connected in order to effectively take in the lubricant into the pocket 8 while preventing displacement of the cage over the axial direction. The center of is different.
As shown in FIGS. 1 and 3, a pair of axial cylindrical surfaces 18a and 18b is provided on both sides in the circumferential direction (left and right direction in FIGS. 1 and 3) in a part of the pocket 8, and the first The spherical concave surface 17 is on one end side (lower end side in FIGS. 1 and 3) of the ball 5 and the second spherical concave surfaces 19 and 19 are on the other end side (upper end in FIGS. 1 and 3). Side) part.
A point O5 in FIG. 3A is a center point of the ball 5 in a state where the ball 5 is assumed to be present at a neutral position in the pocket 8. Under such conditions, the center point O17 of the curvature of the first spherical concave surface 17 is present on the rolling center axis α at a position offset from the center point O5 of the ball 5 to the other end side. . On the other hand, the central point O19 of the curvature of the second spherical concave surfaces 19, 19 is made to be located on one end side of the ball 5 on the rolling center axis α. Accordingly, the extent to which the curvature radii R17 and R19 of the first spherical concave surface 17 and the second spherical concave surface 19 are larger than the curvature radius R5 of the rolling surface of the ball 5 is the center points O5, O17 and O19. Compared to the case of matching.

  As shown in FIG. 3A described above, by shifting the center points O17, O19 of the curvatures of the first spherical concave surface 17 and the second spherical concave surface 19, the first spherical concave surface 17, The minimum values L17, L18, and L19 of the distances between the second spherical concave surface 19 and the axial cylindrical surfaces 18a and 18b and the rolling surface of the ball 5 can be made substantially coincident. As a result of making the minimum values L17, L18, and L19 of these distances substantially coincide with each other, the lubricant can be optimally taken into the pocket 8 while preventing the cage from being displaced in the axial direction. .

This point will be described with reference to the comparative example of FIG.
As shown in FIG. 3B, in the case of a structure in which the center of curvature of the first spherical concave surface 17 and the center of curvature O17, O19 of the second spherical concave surface 19, 19 are matched, a pair of axial When the minimum value L18 'of the distance between the cylindrical surfaces 18a, 18b and the rolling surface of the ball 5 is set to an appropriate value, the minimum value L17', L19 of the distance between each spherical concave surface 17, 19 and the rolling surface of the ball 5 is set. 'Becomes excessive, and the amount of movement of the cage in the axial direction with respect to the ball 5 becomes excessive. As a result, the cage is likely to vibrate during operation of the radial ball bearing. On the contrary, when the minimum values L17 ′ and L19 ′ of the distances between the first spherical concave surface 17 and the second spherical concave surface 19 and the rolling surface of the ball 5 are set to appropriate values, a pair of axial cylindrical surfaces 18a. , 18b and the minimum value L18 'of the distance between the rolling surface of the ball 5 becomes too small, and the lubricant adhering to the running portion of the rolling surface of the ball 5 becomes the opening edge of the axial cylindrical surface 18a, 18b. It becomes easy to be scraped off more than necessary, and the effect of reducing the cage sound is impaired.
On the other hand, as shown in FIG. 3A, if the center points O17 and O19 are shifted, the first spherical concave surface 17, the second spherical concave surface 19, the axial cylindrical surfaces 18a and 18b, and the above The minimum values L17, L18, and L19 of the distance to the rolling surface of the ball 5 are substantially matched to prevent the cage from displacing in the axial direction and optimally incorporate the lubricant into the pocket 8. Can be made.

In order to confirm the effect of the present Example 1, the following tests were conducted, and the abnormal vibration (cage sound) occurrence rate and dynamic friction torque were measured.
A radial ball bearing having an inner diameter of φ12 mm is used, and the incorporated crown type cage is made of synthetic resin. The overall configuration is the same as in the first embodiment, and the first axial cylindrical surface 18a and the second axial cylindrical surface The curvature of 18b is selected from the range of 100 to 111% of the ball diameter ratio, and the diameter of the cylindrical portion constituted by the first axial cylindrical surface 18a and the second axial cylindrical surface 18b is from the range of 100 to 110%. Selected.
[Test conditions]
Rotation speed: 4000rpm
Preload: 5kgf
Lubricant: Grease (30% NS7 enclosed)
Normal temperature and humidity [Test results]
The test results are shown in FIGS. However, the value with the same curvature and diameter of the axial cylindrical surface is outside the scope of the present invention.
In FIG.
A: Both abnormal vibration and torque are good. ○: Either abnormal vibration or torque is within an allowable range. Maximum value x: Either or both of abnormal vibration and torque are large.

  As is apparent from FIG. 4, the curvatures of the first axial cylindrical surface 18a and the second axial cylindrical surface 18b have a ball diameter ratio of 101 to 109%, and the first axial cylindrical surface 18a and the second axial cylindrical surface 18b It can be confirmed that when the diameter D1 of the cylindrical portion constituted by the axial cylindrical surface 18b is 101 to 106%, both the abnormal vibration occurrence rate and the dynamic friction torque can be sufficiently reduced. FIG. 5 shows a case where the diameter D1 of the cylindrical portion constituted by the first axial cylindrical surface 18a and the second axial cylindrical surface 18b is 106% (indicated by ■ in the figure) and 103% larger. In this case (indicated by ▲ in the figure), the abnormal vibration occurrence rate and dynamic friction torque test results are shown.

FIG. 6 shows a second embodiment of the present invention.
In this embodiment, the circumferential clearance S1 in the pocket is set to be the same as the pocket circumferential clearance S10 of the conventional cage, and the curvature radii of the respective axial cylindrical surfaces 18a and 18b are adjusted. The space S2 between the inner and outer diameter edges E1, E2 of the cage pocket 8 and the ball 5 is made larger than the space S20 between the inner and outer diameter edges E1, E2 and the ball 5 of the conventional cage pocket 8. This makes it easy to take in grease into the pocket 8.
As a result, the lubricity in the pocket can be improved, the effect of suppressing vibration and noise due to cage noise and the like can be improved, and the life of the bearing can be extended.
Other configurations and operational effects are the same as those of the first embodiment.

FIG. 7 shows an example of the embodiment in which the pitch circle P8 of the pocket 8 is positioned outside (outer diameter direction) from the pitch circle P5 of the ball 5. In the drawing, the axial cylindrical surface 18X of the conventional cage is shown by a two-dot chain line, and the first axial cylindrical surface 18a and the second axial cylindrical surface 18b of the first embodiment are shown by broken lines.
When practicing the present invention, the pitch circle diameter of the pocket 8 (the diameter of the cylindrical surface connecting the central axes of the curvatures of the axial cylindrical surfaces 18a and 18b) and the pitch circle diameter of the balls 5 do not necessarily have to coincide with each other. However, by shifting both pitch circles P8 and P5 as in this embodiment, the following operational effects can be obtained.

The circumferential clearance S1 can be set smaller than the circumferential clearance S10 of the conventional cage, and the inner edge E1 (or outer diameter edge E2) of the cage pocket 8 and the ball 5 can be made smaller than the space S20 between the inner diameter edge E1 (or outer diameter edge E2) of the conventional cage pocket 8 and the ball 5, thereby suppressing the amount of movement in the radial direction. Is possible.
Furthermore, the space S2 between the outer diameter edge E2 (or inner diameter edge E1) and the ball 5 becomes larger, it becomes easy to take in grease, and lubricity can be improved. The suppression effect is improved.
Furthermore, in the present embodiment, it is shown in comparison with the case of the first embodiment, and even in comparison with this, the effect of suppressing vibrations and noises such as further cage noise is improved.
The magnitude relationship between the pitch circles P8 and P5 can be reversed from that shown in FIG.
Further, in the present embodiment, an example in which the pitch circle P8 of the first axial cylindrical surface 18a and the second axial cylindrical surface 18b is offset in the same radial direction (outer radial direction) is shown. It is also within the scope of the present invention and the design can be changed to set the pitch circles of the cylindrical surface 18a and the second axial cylindrical surface 18b so that one is on the outer diameter side and the other is on the inner diameter side.
Other configurations and operational effects are the same as those in the first or second embodiment.

  The present invention can achieve a remarkable effect by being implemented with a cage incorporated in a small-diameter radial ball bearing such as a miniature bearing. Therefore, the present invention is generally carried out with a synthetic resin crown type cage that is generally used as a cage for a small-diameter radial ball bearing. However, even if the present invention is implemented with a corrugated cage made of a metal plate as shown in FIGS. 8 and 10, a certain effect can be obtained. Of course, such a waveform holder can also be an object of the present invention.

It is a partial expansion perspective view of the holder | retainer in Example 1 of this invention. It is a figure equivalent to the AA section of Drawing 1 showing the state where a ball was held. (A) is Example 1 and (B) is a comparative example, in which the ball is held in the pocket of the cage and the ball is in a neutral position in the pocket. It is the figure seen partially from. It is a figure which shows the test result which measured the abnormal vibration (cage sound) incidence and dynamic friction torque. It is a figure which shows the test result of the abnormal vibration incidence and dynamic friction torque in case the axial cylindrical surface diameter in FIG. 4 is 103% and 106%. It is the elements on larger scale of the holder | retainer in Example 2 of this invention, and is a figure equivalent to the AA cross section of FIG. 1 which shows the state holding the ball | bowl. It is the elements on larger scale of the holder | retainer in Example 3 of this invention, and is a figure equivalent to the AA cross section of FIG. 1 which shows the state holding the ball | bowl. It is a partially cut perspective view showing an example of a ball bearing incorporating a conventionally known cage. It is a perspective view which shows another example of the holder | retainer conventionally known. It is an expanded sectional view which shows the state which hold | maintained the ball | bowl in the holder | retainer shown in FIG. It is an expanded sectional view which shows the state which hold | maintained the ball | bowl in the holder | retainer shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner ring track 2 Inner ring 3 Outer ring track 4 Outer ring 5 Ball 6, 6a Cage 7 Main part 8 Pocket 12 Elastic piece 17 First spherical concave surface 18a First axial cylindrical surface 18b Second axial cylindrical surface 19 Second spherical shape Concave surface α Ball rolling center axis O1 Center point of curvature of first axial cylindrical surface O2 Center of curvature of second axial cylindrical surface O17 Center of curvature of first spherical concave surface O19 Center of second spherical concave surface Curvature center point P5 Ball pitch circle P8 Pocket pitch circle D1 Diameter of the cylindrical portion composed of the first axial cylindrical surface and the second axial cylindrical surface

Claims (2)

In order to hold a plurality of balls in a freely rolling manner, the entire ball is formed in an annular shape, and a radial ball bearing retainer is provided with pockets in a plurality of locations in the circumferential direction.
The first axial cylindrical surface having a radius of curvature larger than the radius of curvature of the rolling surface of the ball, the one end side portion of the portion including the peripheral surface side opening edge of the cage in a part of the inner surface of each pocket,
Similarly, the other end side portion is a second axial cylindrical surface having a radius of curvature larger than the radius of curvature of the rolling surface of the ball,
Assuming that the ball is in a neutral position in the pocket,
The center point of curvature of the first axial cylindrical surface is present at a position on the rolling center axis of the ball that is offset from the center of the ball toward the axial cylindrical surface on the other end side,
One of these pockets is located so that the center point of curvature of the second axial cylindrical surface is located on the rolling center axis of the ball at a position closer to the axial cylindrical surface on one end side than the center of the ball. Is provided on both sides in the circumferential direction,
The curvature of each of the first axial cylindrical surface and the second axial cylindrical surface is regulated to 101 to 109% of the ball diameter, and the first axial cylindrical surface and the second axial cylindrical surface are The diameter of the configured cylindrical part is regulated to 101 to 106% of the ball diameter,
The one end side portion of the rolling center axis of the ball held in the pocket at the remaining part of the inner surface of each pocket is a first spherical concave surface having a radius of curvature larger than the radius of curvature of the rolling surface of the ball,
Similarly, the other end side portion is a second spherical concave surface having a radius of curvature larger than the radius of curvature of the rolling surface of the ball,
Assuming that the ball is present in a neutral position in the pocket, the center point of curvature of the first spherical concave surface is shifted to the other end side from the center of the ball on the rolling center axis of the ball. Exists in position,
A radial ball bearing retainer, wherein a center point of curvature of the second spherical concave surface is present at a position offset toward one end from the center of the ball on the rolling center axis of the ball. An inner ring having an inner ring raceway on an outer peripheral surface and an outer ring having an outer ring raceway on an inner peripheral surface are arranged concentrically with each other, and the radial ball bearing retainer according to claim 1 is disposed between the inner ring raceway and the outer ring raceway. It consists of a plurality of balls that are freely rollable in a plurality of pockets provided,
A radial characterized in that the pitch circle diameter of each pocket is different from the diameter of the pitch circle of each ball, and the pitch circle of each pocket is located outside or inside the pitch circle of each ball. Ball bearing.

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