JP2001355637A - Ball bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a long-service-life ball bearing having less possibility of lubricant such as grease leaking out the outside of the bearing. SOLUTION: This ball bearing is provided with an inner ring, an outer ring, a plurality of balls 10 rotatably disposed between the inner ring and the outer ring, a retainer 1 retaining the plurality of balls 10 between the inner ring and the outer ring and extending into an annular shape, and the lubricant being formed between the inner ring and the outer ring and filling the clearance portion internally providing the balls 10. The shape of the inside face 4a of a plurality of pockets 4 provided in the retainer 1 is set to an approximately elliptical shape with the diameter in the extending direction of the retainer 1 set to the long diameter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ball bearing provided with a cage.

[0002]

2. Description of the Related Art Conventionally, in a cage provided in a ball bearing, the shape of the inner surface of a pocket is spherical (true spherical) (that is, the cross-sectional shape of the annularly continuous pocket in the continuous direction is a perfect circle). T).

[0003]

However, in the conventional ball bearing, since a rolling element having a spherical shape (a cross-sectional shape is a perfect circle) is housed in a pocket having a spherical inner surface as described above, Almost the entire inner surface of the pocket comes into contact with the surface of the rolling element. Therefore, when the bearing rotates, almost the entire inner surface of the pocket slides on the surface of the rolling element, so that the lubricant such as grease attached to the surface of the rolling element is easily and easily scraped off. It was difficult for the lubricant to adhere again later.
As a result, lubrication inside the bearing is likely to be insufficient, and the bearing may have a short life.

Further, since there is almost no space between the rolling element and the pocket, a lubricant such as grease cannot accumulate between the rolling element and the pocket. As a result, the lubricant may flow out into another space inside the bearing, and in the worst case, the lubricant may leak out of the bearing. Therefore, an object of the present invention is to solve the problems of the conventional ball bearing as described above, and to provide a ball bearing having a long life and a low possibility that a lubricant such as grease leaks out of the bearing. I do.

[0005]

In order to solve the above problems, the present invention has the following arrangement. That is, the ball bearing of the present invention includes an inner ring, an outer ring, a plurality of rolling elements disposed so as to freely roll between the inner ring and the outer ring, and the plurality of rolling elements between the inner ring and the outer ring. A retainer that holds a moving body and is annularly continuous, a lubricant formed between the inner ring and the outer ring, and a lubricant filled in a gap portion in which the rolling element is provided,
, At least one of the plurality of pockets provided in the cage has a substantially elliptical surface whose inner surface has a major axis whose diameter in the continuous direction of the cage.

With such a configuration, almost the entire inner surface of the pocket does not come into contact with the surface of the rolling element, and a part of the inner surface of the pocket, specifically, the inner surface of the pocket, Only the lower part (bottom part) and the upper part (near the opening part) of the pocket come into contact with the surface of the rolling element. Then, when the ball bearing rotates, the possibility that the lubricant such as grease adhered to the surface of the rolling element is scraped is low, and even when the lubricant is scraped, the surface of the rolling element may be scraped off. Easy to reattach. as a result,
The lubrication inside the ball bearing becomes sufficient, and the ball bearing has a long life.

[0007] Further, a space is formed between the inner surface of the pocket and the surface of the rolling element, and the lubricant can accumulate in the space. The likelihood of leakage to the outside is reduced.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a ball bearing according to the present invention will be described below in detail with reference to the drawings. FIG.
Is a cage 1 provided in the ball bearing (not shown) of the present embodiment.
2 is a developed cross-sectional view taken along line AA of FIG. The ball bearing according to the present embodiment includes an inner ring, an outer ring, a plurality of balls 10 arranged to be rollable between the two wheels, and a plurality of balls 10 held between the two wheels so as to be annularly continuous. Vessel 1
And a lubricant such as grease filled between the two wheels and filled in the gap in which the ball 10 is provided (however, the inner ring, the outer ring, etc. are not shown).

The cage 1 is a crown type cage, and has an annular portion 2.
And a plurality of elastic members 3 protruding from one surface of the annular portion 2 in the axial direction. A concave pocket 4 for accommodating the ball 10 is formed between an adjacent pair of three 3,3, and the ball 10 is held by the pair of three 3,3 and the pocket 4. The inner surface 4a of the pocket 4 is an elliptical surface whose major axis is the diameter of the retainer 1 in the continuous direction (the circumferential direction of the annular retainer 1). That is, the inner surface 4a of the pocket 4 has a shape such that the space surrounded by the inner surface 4a has an elliptical shape. This will be described with reference to the drawings.
As shown in (1), it has a substantially elliptical shape having a major diameter in the circumferential direction and a minor diameter in the axial direction.

With such a configuration, in the case of the conventional ball bearing, almost the entire inner surface of the pocket is in contact with the surface of the ball, whereas in the case of the ball bearing of the present embodiment, the pocket 4
Of the inner surface 4a, specifically, only the lower portion 5 (bottom portion) and the upper portion 6 (near the opening of the pocket 4) of the pocket 4 in the inner surface 4a are in contact with the surface of the ball 10. Then, when the ball bearing rotates, it is unlikely that the lubricant adhering to the surface of the ball 10 will be scraped off, and even if the lubricant is scraped off, it will easily adhere to the surface of the ball 10 again. As a result, lubrication inside the ball bearing becomes sufficient, and the ball bearing has a long life.

A space 7 is formed between the inner surface 4a of the pocket 4 and the surface of the ball 10 (because the major axis of the elliptical surface is larger than the diameter of the ball 10), so that the lubricant can be stored. Since the space 7 functions as a lubricant reservoir, the possibility that the lubricant leaks out of the ball bearing is reduced. Note that the present embodiment is an example of the present invention, and the present invention is not limited to the present embodiment.

For example, the present invention can be applied to various ball bearings such as deep groove ball bearings, angular ball bearings, and thrust ball bearings. In this embodiment, the cage is a crown type cage. However, there is no problem with other types of cages. For example, a shape holder, a waveform holder, a matching holder, and the like.

Further, examples of the material of the retainer include a metal such as steel and a resin. As the resin, for example,
Polyamide resin such as nylon 66 and nylon 46, PT
Fluorine resins such as FE and ETFE; ether ketone resins such as polyether ether ketone resin (PEEK); polyether sulfone resin (PES); polyoxymethylene resin (POM); polybutylene terephthalate resin (PBT); Type polyphenylene sulfide resin (L-PPS) and the like.

Fibers may be added to these resins in order to impart strength. Examples of preferably used fibers include glass fibers, carbon fibers, aramid fibers, and various whiskers. The fiber content is
It is appropriately selected in consideration of moldability, assemblability, and the like in addition to the strength of the cage. Usually, it is 5 to 40% by weight. Furthermore,
The kind of the lubricant is not particularly limited, and any kind of lubricant such as grease may be used as long as it is a usual lubricant used for a ball bearing.

Further, the material of the ball 10 may be steel or ceramic. Further, in the present embodiment, the ball bearing may or may not include the seal.

[0016]

As described above, the ball bearing of the present invention has a low possibility that the lubricant such as grease adhered to the surface of the rolling element during the rotation of the ball bearing is scraped off. Further, even when the lubricant is scraped off, the lubricant easily adheres to the surface of the rolling element. Therefore, lubrication inside the ball bearing is sufficient, and the ball bearing has a long life.

Further, the possibility that the lubricant leaks out of the ball bearing is low.

[Brief description of the drawings]

FIG. 1 is a plan view of a cage provided in a ball bearing according to an embodiment.

FIG. 2 is an expanded sectional view taken along line AA of FIG.

[Explanation of symbols]

 1 cage 4 pocket 4a inner surface 10 balls

Claims (1)

[Claims] 1. An inner ring, an outer ring, a plurality of rolling elements rotatably disposed between the inner ring and the outer ring, and the plurality of rolling elements between the inner ring and the outer ring. A ball bearing comprising: a ring-shaped continuous cage; and a lubricant formed between the inner ring and the outer ring, and filled in a gap in which the rolling element is provided. A ball bearing characterized in that at least one of the plurality of pockets has an inner surface having a substantially elliptical surface whose major axis has a diameter in the continuous direction of the cage.