JP2001241449A - Waveform cage for ball bearing and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waveform cage for a ball bearing and its manufacturing method capable of preventing generation of abnormal sound due to self-excited vibration by positively holding a ball 2 at a bottom of a ball retaining part 3 so that this ball 2 does not come into contact with an edge of the ball retaining part 3. SOLUTION: Inner circumferential faces of each ball retaining parts 3 of two annular retaining plates 1 are provided so that they are wider with larger radius of curvature as they near circumferential rim parts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ball bearing wave retainer for holding a ball of a ball bearing and a method of manufacturing the same.

[0002]

2. Description of the Related Art FIG. 4 shows an example of the configuration of a wave retainer for a ball bearing for a radial ball bearing. This wave retainer for ball bearings has 2
Eight balls 2 are sandwiched between two annular holding plates 1 so as to be able to rotate. Each of the two annular holding plates 1 has ball holding portions 3 bulging in a hemispherical shape at eight locations at equal intervals in the circumferential direction. In addition, these two annular holding plates 1 face each ball holding portion 3 on the opening side, and
The balls 2 are held in the pockets formed thereby, and the space between the ball holding portions 3 is fixed with rivets 4. The ball bearing waveform retainer configured as described above becomes a radial ball bearing by being inserted between an outer ring and an inner ring (not shown).

As shown in FIG. 5, in a conventional ball bearing waveform retainer, the radius of curvature of the inner peripheral surface of each ball holding portion 3 forming a pocket is substantially the same as or slightly larger than the radius r of the ball 2. Was formed in a large uniform radius. As shown in FIG. 6, such a ball holding portion 3 includes a convex mold 5 having a hemispherical outer peripheral surface having a radius of curvature substantially equal to the radius r of the ball 2,
The thickness t of the annular holding plate 1 is determined by the radius of curvature of the outer peripheral surface of the convex mold 5.
The annular holding plate 1 is formed by pressing the annular holding plate 1 with a concave mold 6 having a hemispherical inner peripheral surface having a radius of curvature to which is added.

[0004]

However, since the inner peripheral surface of the ball holding portion 3 has a uniform radius of curvature substantially equal to or slightly larger than the radius r of the ball 2, it is shown by cross hatching in FIG. In the area B of almost the entire inner peripheral surface, the ball 2
Will be held. For this reason, the conventional ball bearing wave retainer uses a traction force between the inner peripheral surface of the ball holding portion 3 and the ball 2, particularly when high viscosity grease is used as a lubricant. The wave retainer whirls, thereby forming the ball holding portion 3 forming a pocket.
Since the edge of the joint is in contact with the ball 2, the lubrication mode of the contact surface may become boundary lubrication and cause self-excited vibration, which causes a problem that abnormal noise is generated by the self-excited vibration.

The present invention has been made in order to cope with such a situation, and the self-excitation is performed by increasing the radius of curvature while expanding the inner peripheral surface of the ball holding portion for holding the ball toward the periphery. It is an object of the present invention to provide a ball bearing waveform retainer capable of preventing generation of abnormal noise due to vibration and a method of manufacturing the same.

[0006]

According to a first aspect of the present invention, there is provided a wave bearing for a ball bearing, wherein two hemispherical ball holding portions are formed at a plurality of positions in a circumferential direction at predetermined intervals. In a ball bearing waveform retainer configured by holding each ball in a pocket formed by opposing each ball holding portion on the opening side and combining them, the ball holding portion of each of the two annular holding plates is In the inner peripheral surface, the distance from the center of the opening surface of the ball holding portion at the bottom is slightly longer than the radius of the ball, and the closer to the periphery, the longer the distance, and the radius of curvature of the ball holding portion is the bottom. Is characterized in that the radius of curvature is substantially the same as or slightly larger than the radius of the ball, and the radius of curvature is further increased toward the periphery.

According to the first aspect of the present invention, at the bottom of the ball holding portion, the inner peripheral surface has a radius of curvature along the ball. Is increased so that the ball does not contact the seam edge of the ball holding portion constituting the pocket, thereby making it possible to prevent the generation of abnormal noise due to self-excited vibration.

According to a second aspect of the present invention, there is provided a method of manufacturing a wave bearing for a ball bearing, wherein the annular holding plate is swelled into a hemisphere by pressing a plurality of circumferential portions at predetermined intervals with a hemispherical convex shape and a concave shape. A ball holding portion is formed, and two annular holding plates are provided. In the method of manufacturing a ball bearing waveform holder for holding and combining balls in pockets formed by facing each ball holding portion on the opening side, The radius of curvature of the convex outer peripheral surface is made substantially the same as or slightly larger than the radius of the ball, and the radius of curvature of the concave inner peripheral surface is calculated by adding the thickness of the annular holding plate to the radius of curvature of the convex outer peripheral surface. It is characterized in that it is formed larger than the one formed.

According to the second aspect of the present invention, since the ball holding portion of the annular holding plate is pressed by the convex shape having a small radius of curvature and the concave shape having a large radius of curvature, the bottom portion of the inner peripheral surface of the ball holding portion is pressed. The radius of curvature of the ball is a perfect molding surface that follows the radius of curvature of the convex shape and follows the ball, but the peripheral edge of the inner peripheral surface of the ball holding portion has a gap between the convex shape and the concave shape that is the thickness of the annular holding plate. Therefore, the surface is not completely formed, but becomes a curved surface having a larger radius of curvature while expanding as it approaches the edge. Therefore, the ball bearing wave retainer manufactured by this manufacturing method,
The spinning ball is securely held at the bottom of the ball holding portion having the slowest peripheral speed, and the gap between the ball and the ball is increased toward the peripheral portion, so that the ball holds the joint of the ball holding portion. By not touching the edge of the ball and reducing the traction force between the ball and the inner surface of the cage,
Generation of abnormal noise due to self-excited vibration can be prevented.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 3 show an embodiment of the present invention. FIG. 1 is an enlarged sectional view of a ball holding portion of the wave bearing for a ball bearing shown in FIG. 2 is an enlarged vertical sectional view showing a pressing step of forming a ball holding portion on an annular holding plate,
FIG. 3 is a partially enlarged front view of the ball bearing waveform retainer. Components having the same functions as those of the conventional example shown in FIGS. 4 to 7 are denoted by the same reference numerals.

In this embodiment, a description will be given of a ball bearing waveform retainer for a radial ball bearing similar to the conventional example shown in FIG. 4 and a method of manufacturing the same. This wave retainer for ball bearings has 2
The two annular holding plates 1 are overlaid and fixed with rivets 4,
The balls 2 are held in pockets formed by the ball holding portions 3 facing each other on the opening side. However,
In the present embodiment, the shape of the inner peripheral surface of the ball holding section 3 is different from the conventional example.

That is, as shown in FIG. 1, each ball holding portion 3 of the annular holding plate 1 in the ball bearing waveform holder of the present embodiment.
Is the distance from the center C of the opening surface of the ball holding portion (the center of the opening of the ball holding portion 3 on the surface along the upper surface of the annular holding plate 1 in the lower annular holding plate 1 in the figure). (The lower end portion of the lower annular holding plate 1 in the figure) is replaced with a ball 2 as in the prior art.
Is slightly longer than the radius r of
This distance is formed so as to be further longer toward the periphery. The radius of curvature of the inner peripheral surface at the bottom of the ball holding portion 3 is almost the same as or slightly larger than the radius r of the ball 2, but the radius of curvature (r
+ Α) increases. Therefore, the distance from the center C of the opening surface is long at the peripheral portion of the inner peripheral surface of the ball holding portion 3.
The gap between the ball 2 becomes large. Further, at the bottom of the inner peripheral surface of the ball holding portion 3, since the radius of curvature follows the outer peripheral surface of the ball 2 having substantially the same radius of curvature, the ball 2 can be reliably held at the center of the pocket. For this reason, there is no possibility that the ball 2 comes into contact with an edge of the joint of the ball holding portion 3 constituting the pocket. Further, since the ball 2 rotates around an axis connecting the bottoms of the ball holding portions 3 on both sides constituting the pocket, the portion where the peripheral speed of the ball 2 is the smallest is held only by the bottom of the ball holding portion 3. And thus the traction force is also reduced.

A method for manufacturing a ball bearing wave retainer provided with the ball holding portion 3 having the above inner peripheral surface shape will be described. As shown in FIG. 2, the ball holding portion 3 has a convex mold 5 having a hemispherical outer peripheral surface having a radius of curvature substantially equal to or slightly larger than the radius r of the ball 2, and an outer periphery of the convex mold 5. By pressing the annular holding plate 1 with a concave mold 7 having a hemispherical inner peripheral surface having a radius of curvature (r + t + β) larger than the radius of curvature of the surface plus the thickness t of the annular holding plate 1. It is formed. As in the conventional example shown in FIG. 6, the convex mold 5 has a complete hemispherical protrusion except for a rounded portion at the peripheral edge. However, the concave mold 7 is different from the conventional concave mold 6.
Although the depth is the same as that of the sphere, the radius of curvature is large, so that the concave is less than half of the sphere.

According to the above manufacturing method, the annular holding plate 1 is pressed between the projection of the convex mold 5 and the recess of the concave mold 7 to form the ball holding section 3 which bulges into a hemisphere. At this time, since the bottom of the ball holding portion 3 is pressed at a portion where the top of the protrusion of the convex mold 5 and the bottom of the recess of the concave mold 7 overlap with a gap substantially equal to the thickness t of the annular holding plate 1, it is completely formed. The radius of curvature is substantially the same as that of the convex mold 5. However, since a gap is formed between the protrusion of the convex mold 5 and the depression of the concave mold 7 at the peripheral edge of the ball holding unit 3, the radius of curvature of the concave mold 7 becomes larger than the radius of curvature of the convex mold 5 as the distance from the bottom increases. As it approaches, this radius of curvature gradually increases. In addition, in the peripheral portion of the ball holding portion 3, the convex 5
, The distance from the center C of the opening surface also gradually increases and spreads around.

As described above, according to the ball bearing waveform retainer of this embodiment and the method of manufacturing the same, the ball 2 has the area D at the bottom of the inner peripheral surface of the ball retaining portion 3 indicated by cross hatching in FIG. Therefore, the ball 2 can be reliably held at the center of the pocket. Moreover, FIG.
As shown in (1), since a gap is formed between the ball 2 and the peripheral portion of the ball holding portion 3, the ball 2 does not come into contact with the joint edge of the ball holding portion 3. . Therefore, in the ball bearing waveform retainer, whirling hardly occurs due to the traction force between the ball 2 and the ball 2. Since there is no contact with the peripheral portion, generation of abnormal noise due to self-excited vibration can be prevented.

In the above-described embodiment, the case where the two annular holding plates 1 of the ball bearing wave retainer are fixed with the rivets 4 has been described. However, these annular holding plates 1 can be combined by an arbitrary method. it can.

In the above embodiment, the description has been given of the ball bearing waveform retainer used for the radial ball bearing. However, the present invention can be similarly applied to a ball bearing waveform retainer of a thrust ball bearing.

[0019]

As is apparent from the above description, according to the ball bearing waveform retainer of the present invention and the method of manufacturing the same, the radius of curvature increases while the ball retaining portion of the annular retaining plate expands toward the periphery. Since the ball has an appropriate inner peripheral surface, the ball can be reliably held at the bottom of the ball holding portion, and can be prevented from coming into contact with the edge of the ball holding portion, thereby preventing generation of abnormal noise due to self-excited vibration. Become like

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention, and FIG.
FIG. 5 is an enlarged cross-sectional view of the ball holding portion of the ball bearing waveform retainer taken along line AA of FIG.

FIG. 2, showing an embodiment of the present invention, is an enlarged longitudinal sectional view illustrating a pressing step of forming a ball holding portion on an annular holding plate.

FIG. 3, showing an embodiment of the present invention, is a partially enlarged front view of a wave retainer for a ball bearing.

4A and 4B are a front view and a side view of the ball bearing wave retainer.

5 is an enlarged cross-sectional view showing a conventional example and showing an AA line of a ball holding portion in the ball bearing waveform holder of FIG. 4; FIG.

FIG. 6 is an enlarged longitudinal sectional view showing a conventional example and showing a pressing step of forming a ball holding portion on an annular holding plate.

FIG. 7 shows a conventional example, and is a partially enlarged front view of a waveform retainer for a ball bearing.

[Explanation of symbols]

 Reference Signs List 1 annular holding plate 2 ball 3 ball holding portion 5 convex 7 concave

Claims (2)

[Claims] 1. An annular holding plate in which hemispherically bulging ball holding portions are formed at a plurality of positions in a circumferential direction at predetermined intervals,
In a ball bearing wave retainer configured by holding and combining balls in pockets formed by facing the respective ball holding portions on the opening side, the inner circumference of each ball holding portion of two annular holding plates The distance from the center of the opening surface of the ball holding portion to the bottom is slightly longer than the radius of the ball at the bottom, and this distance is further increased toward the periphery, and the radius of curvature of the ball holding portion is Characterized in that the radius of curvature is substantially the same as or slightly larger than the radius of curvature, and the radius of curvature is further increased toward the periphery. 2. A ball holding portion is formed by pressing a plurality of locations in the circumferential direction of the annular holding plate at predetermined intervals with a hemispherical convex shape and a concave shape so as to bulge into a hemispherical shape. In a method for manufacturing a ball bearing waveform retainer for combining two balls by holding the balls in pockets formed by facing the respective ball holding portions on the opening side, the curvature radius of the convex outer peripheral surface is defined as the radius of the ball. A ball characterized by being substantially the same or slightly larger, and having a radius of curvature of the concave inner peripheral surface larger than the radius of curvature of the convex outer peripheral surface plus the thickness of the annular holding plate. Manufacturing method of waveform retainer for bearing.