JP2003278762A - Rolling element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling element which is easy to produce, compact and has a large load capacity. <P>SOLUTION: The rolling element 4 has a width W set to be smaller than its outside diameter D, and the portion 4E of its outer periphery close to a transverse end thereof is machined into a projecting arcuate shape with a radius r4 of curvature slightly smaller than the inner radius r<SB>3</SB>of curvature of an outer cylinder 3. The portion of the outer periphery of the rolling element 4 near its transverse center 4C is cylindrical and a retainer 5 retaining the rolling element 4 is packed between a guide shaft 2 and the outer cylinder 3, so that the outer periphery of the rolling element 4 makes contact with the interior wall of the outer cylinder 3 at its portions 4E close to both transverse ends and makes contact with the guide shaft 2 at its portion close to the transverse center 4C. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling element used for a bearing which is easy to manufacture, compact, and has a large load capacity.

[0002]

2. Description of the Related Art Conventionally, rolling elements generally used for bearings include a steel ball and a roller roller. The roller roller has a cylindrical outer shape, a convex arc shape, and both end portions have a convex arc shape. There are some with a concave arc at the center. It can be said that all of these roller rollers are formed in a shape in which the width dimension is larger than the outer diameter dimension. By the way, in a bearing, for example, the range in which a roller roller having a width of several millimeters receives a load (the size of the contact ellipse) varies depending on the magnitude of the load, the difference in the curvature of the contact surface, etc., but the major axis of the contact ellipse usually exceeds 1 mm. Things are rare.

[0003]

Therefore, if the width of the roller roller is 1 mm or more, there is no problem in use even if it is smaller than the outer diameter of the roller roller, and the width dimension as described above is unnecessary, and rather, This occupies an extra space, which limits the number of housings incorporated in the bearing and limits the load capacity. Further, when the outer shape of the roller roller having a large width is processed into a different shape, the machining allowance is increased, and the processing time is correspondingly consumed. The present invention has been proposed in order to improve the above inconvenience, and an object thereof is to provide a rolling element that is easy to manufacture, compact, and has a large load capacity.

[0004]

In order to solve the above-mentioned problems, according to the present invention, in claim 1, the width dimension is set smaller than the outer diameter dimension, and a part of the outer peripheral portion,
Alternatively, a rolling element formed by processing the whole into an arc shape is disclosed.
According to the present invention, in claim 2, the width dimension is set smaller than the outer diameter dimension, and both ends of the outer peripheral portion are processed into a convex arc shape, and the central portion is processed into a cylindrical shape. Disclose. Further, according to the present invention, in claim 3, the width dimension is set smaller than the outer diameter dimension, and both ends of the outer peripheral portion are processed into an arc shape and the central portion is processed into a concave arc shape. Disclose.

According to the first aspect, it is possible to reduce the volume removed by machining, facilitate the machining, and shorten the time required for the machining. Also, by setting the width dimension smaller than the outer diameter dimension, it is possible to incorporate more in the bearing compared to the conventional rolling elements,
The load capacity of the entire bearing can be increased.

According to the second aspect, both end portions of the outer peripheral portion are processed into a convex arc shape, and the central portion is processed into a cylindrical shape. It has a small stock removal and is easy to process. Moreover, since the convex arcuate portions on both ends of the outer peripheral portion are in contact with the inner wall of the outer cylinder of the bearing, the load is dispersed, the contact pressure per unit area is reduced, and the load capacity can be increased as a whole. it can.

According to the third aspect of the present invention, both ends of the outer peripheral portion are processed into an arc shape, and the central portion is processed into a concave arc shape. The load is dispersed by the contact of the points, and the load capacity is further increased by the contact of the central portion of the concave arc shape with the outer circumference of the shaft.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION One embodiment of a rolling element according to the present invention will be described below with reference to the accompanying drawings. A bearing 1 is shown in FIG. 1, and in order to support an outer cylinder 3 on a guide shaft 2 so as to be relatively movable in the axial direction of the guide shaft 2, a large number of bearings are provided between the guide shaft 2 and the outer cylinder 3. The retainer 5 holding the rolling element 4 is interposed. In the retainer 5, holding holes 6 for rotatably holding the rolling elements 4 are arranged at predetermined intervals so that a tangent line of a concentric circle passing through the middle of the meat part is used as a rotation center axis. The tangents are respectively orthogonal to the moving direction of the rolling elements, that is, the longitudinal axis of the guide shaft 2.

The rolling element 4 in the bearing 1 is
As shown in FIG. 2, the width W dimension is set smaller than the outer diameter D dimension, and the outer circumferential portion 4E is provided near the width direction end portion 4E.
It is machined into a convex arc shape with a radius of curvature r4 slightly smaller than the inner radius of curvature r3 (see FIG. 3). The vicinity of the widthwise central portion 4C of the outer peripheral portion of the rolling element 4 is cylindrical. The rolling element 4 may be made of steel, or may be made of any material as long as it has strength characteristics equal to or higher than that of steel.

According to the rolling element 4 of the present invention, the outer diameter D
By setting the width W to be smaller than the size, it is possible to incorporate a large number in the bearing 1 and to increase the load capacity of the bearing 1 as a whole, as compared with the rolling elements used so far. Further, by comparing the widthwise end portion 4E of the outer peripheral portion of the rolling element 4 with a convex arc shape and the widthwise central portion 4C of the outer peripheral portion with a cylindrical shape, comparison is made with a method of processing the entire outer peripheral portion into an arc shape. Therefore, the machining allowance is small and the machining is easy.

When the rolling element 4 is held in the holding hole 6 of the retainer 5 and the retainer 5 is loaded between the guide shaft 2 and the outer cylinder 3, the outer peripheral portion of the rolling element 4 is 4E of the width direction end portion of the outer tube 3 is in contact with the inner wall of the outer cylinder 3, while the guide shaft 2 is a cylindrical width direction central portion 4C.
The neighboring areas come into contact with each other (see FIG. 3). In this way, the inner wall of the outer cylinder 3 of the bearing 1 is in contact with the widthwise end portion 4E, which is a convex arcuate portion on both ends of the outer peripheral portion, so that the load is dispersed and the contact pressure per unit area is It is possible to reduce the load capacity and increase the load capacity as a whole. In addition, it is not necessary to form a rolling groove or the like on the guide shaft 2 side, and the manufacturing is easy. Further, by processing the outer peripheral portion of the rolling element 4 in the widthwise end portion 4E into a convex arc shape, unlike the conventional cylindrical roller or the like, the contact resistance between both ends of the rolling peripheral surface and the holding hole 6 is reduced. It is not necessary to process the edge of the holding hole to prevent the frictional heat generated by the local contact resistance between both ends of the rolling surface and the holding hole, and high-speed rotation is possible (see FIG. 4). ).

The rolling element 4 according to the present invention can also be constructed as follows. In the rolling element 4 in this case, the width W dimension is set to be smaller than the outer diameter D dimension, and the outer peripheral portion near the widthwise end portion 4E is formed in a convex arc shape and the vicinity of the widthwise central portion 4C is provided. It is processed into a concave arc shape (see FIG. 5). The rolling element 4 is formed in a convex arc shape,
The radius of curvature r4 near the end in the width direction is made slightly smaller than the inner radius of curvature r3 of the outer cylinder 3 so as to be in contact with the inner wall of the outer cylinder 3, and the vicinity of the central portion 4C in the width direction machined into a concave arc shape. The radius of curvature ro is set to be slightly larger than the radius r2 of the guide shaft 2 so that the vicinity of the central portion 4C in the width direction is in contact with the guide shaft 2 (see FIG. 6).

Even in the rolling element 4 as described above, the outer diameter D
By setting the width W to be smaller than the size, it is possible to incorporate a large number of the rolling elements into the bearing 1 and to increase the load capacity of the entire bearing, as compared with the conventional rolling elements. Similarly, since both of the width direction end portions 4E formed in the convex arc shape come into contact with the inner wall of the outer cylinder 3, the load is dispersed, and the outer circumference of the guide shaft 2 has a concave arc shape. The load capacity is further increased by the contact of the widthwise central portion 4C. Further, also in such rolling element 4, the guide shaft 2
Since it is not necessary to process rolling grooves on the side, it is easy to manufacture.

[0014]

EFFECTS OF THE INVENTION According to the present invention, (1) the volume removed by processing can be reduced, processing becomes easier, and the time required for processing can be shortened. Further, by setting the width dimension smaller than the outer diameter dimension, it is possible to incorporate a larger number of the rolling elements into the bearing and to increase the load capacity of the entire bearing, as compared with the conventional rolling elements. (2) Compared with the method of machining the entire outer peripheral portion in an arc shape by processing both end portions of the outer peripheral portion into a convex arc shape and the central portion into a cylindrical shape, the machining allowance is small, and machining Is easy. Moreover, since the convex arcuate portions on both ends of the outer peripheral portion are in contact with the inner wall of the outer cylinder of the bearing, the load is dispersed, the contact pressure per unit area is reduced, and the load capacity can be increased as a whole. it can. (3) Since both ends of the outer peripheral portion are processed into an arc shape and the central portion is processed into a concave arc shape, the outer cylinder inner wall of the bearing is brought into contact with the arcuate portions on both end portions of the outer peripheral portion, so that a load is applied. Are dispersed, and the central portion of the concave arc shape is in contact with the outer circumference of the shaft, so that the load capacity is further increased.

[0015]

[Brief description of drawings]

FIG. 1 is a sectional view showing one embodiment of a bearing using a rolling element according to the present invention.

FIG. 2 is an enlarged side view showing an example of a rolling element according to the present invention.

FIG. 3 is an enlarged explanatory view of a contact portion between the rolling element and the outer cylinder shown in FIG.

FIG. 4 is an explanatory view showing a state where the rolling element shown in FIG. 2 is inserted into a holding hole in a retainer.

FIG. 5 is an enlarged side view showing another example of the rolling element according to the present invention.

FIG. 6 is an enlarged explanatory diagram of a contact portion between the rolling element, the outer cylinder, and the guide shaft shown in FIG.

[Explanation of symbols]

1 bearing 2 Guide shaft 3 outer cylinder 4 rolling elements 4E Width direction end 4C width direction central part 5 retainer 6 holding holes

Claims (3)

[Claims] 1. A rolling element characterized in that a width dimension is set smaller than an outer diameter dimension, and part or all of an outer peripheral portion is processed into an arc shape. 2. A rolling element characterized in that the width dimension is set smaller than the outer diameter dimension, and both end portions of the outer peripheral portion are processed into a convex arc shape and the central portion is processed into a cylindrical shape. 3. A rolling element characterized in that the width dimension is set smaller than the outer diameter dimension, and both end portions of the outer peripheral portion are processed into an arc shape and the central portion is processed into a concave arc shape.