JPH0742733A - Linear ball bearing - Google Patents

Abstract

(57) [Abstract] [Purpose] To facilitate the positioning between the components and to achieve a smooth circulating movement of the ball. [Structure] The linear groove 5 is formed in the bearing body 2 at a position exposed from the inner wall of the bearing body 2, and is formed so as to penetrate through the wall of the bearing body 2. Further, inner grooves 7 of the swirl groove 6 are formed at both ends of the bearing body 2, and the straight grooves 5 of the load region P and the unloaded region L are connected by the inner groove 7. An outer groove 8 of the turning groove 6 is formed in the end cap 3 in an arc shape. The outer groove 8 is projected to form a tongue-shaped projection 9, which is fitted into the linear groove 5 of the bearing body 2 to form the end cap 3
Is joined to a predetermined position, and the bearing ball b is picked up to promote the turning. [Effects] The assembling process is facilitated, and smooth circulation is possible without obstructing the circulation of the balls.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear ball bearing applied to linear motion parts of general office equipment, industrial machines, robots and the like.

[0002]

2. Description of the Related Art Conventionally, there has been a linear ball bearing having a structure in which a retainer having a number of endless tracks of bearing balls is mounted on an inner wall of a hollow bearing body. In addition, recently, a structure has been adopted in which an outer cylinder integrated with a retainer and end caps are joined to both ends of the outer cylinder, and a straight groove of the infinite circulation groove is formed on the outer cylinder side, and a swirl groove is formed on the end cap. There is a structure that circulates the ball. In such a linear ball bearing, it is a problem to join the straight groove of the infinite circulation groove and the swiveling groove without displacement so as not to hinder the smooth circulation movement of a large number of balls. A protrusion for positioning is formed on the end cap or the outer cylinder in order to improve the mounting accuracy of the end cap to the end cap.

[0003]

However, with such a means, unless the machining accuracy is considerably improved, even if the end cap is assembled to the outer cylinder by the projection for positioning, the straight groove and the swirling groove of the infinite circulation groove are formed. However, there is a problem that the ball is displaced and the smooth circulation movement of the ball is hindered. The present invention has been made to improve such inconvenience, and facilitates the positioning between the component parts, improves the assembling accuracy, and joins the straight groove portion and the swivel groove portion of the infinite circulation groove so as not to be displaced. An object of the present invention is to provide a linear ball bearing capable of achieving a smooth circulating movement of a ball.

[0004]

In order to solve the above-mentioned problems, the present invention has a hollow bearing main body and end caps that are joined to both ends of the bearing main body. The straight groove that constitutes the infinite circulation groove of the bearing ball is formed at the position exposed from the inner wall of the bearing body to form the load region, while it is formed so as to penetrate through the wall of the bearing body to form the no-load region. An inner groove forming a swirl groove is formed at both ends of the bearing body, and the inner groove connects the linear grooves of the load region and the no-load region, and the end cap has an outer groove forming a swirl groove. At the joint surface of the end cap with the bearing body, the end groove is fitted into the straight groove of the bearing body to join the end cap at a predetermined position, and the bearing ball is scooped up for swiveling. Characterized in that a be tongue-like projection. In the above configuration, the bearing body and / or the end cap can be made of synthetic resin. Furthermore, the bearing body and / or the end cap can be made of ceramics.

[0005]

It is easy to position and join the end cap to the bearing body at a predetermined position. At that time, the tongue-shaped projection is formed when the ball travels from the straight groove to the turning groove.
Since the turning of the ball is promoted, the influence of the joint surface can be suppressed as much as possible, and the smooth circulation can be achieved without obstructing the circulation of the ball. Since the bearing body or the end cap can be formed of synthetic resin or ceramics, it is easy to process and the manufacturing cost can be suppressed.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the linear ball bearing according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a linear ball bearing 1. The linear ball bearing 1 has a hollow bearing body 2 and end caps 3 that are joined to both ends of the bearing body 2. The bearing body 2 is provided with a straight groove 5 which constitutes an infinite circulation groove 4 of a large number of bearing balls b.
It is formed at a position exposed from the inner wall, and is formed so as to penetrate through the wall of the bearing main body 2. The straight groove 5 exposed from the inner wall of the bearing body 2 is a load region P, and the straight groove 5 penetrating the inside of the bearing body 2 wall is a no-load region L. Further, inner grooves 7 of the swirl groove 6 are formed at both ends of the bearing body 2, and the straight grooves 5 of the load region P and the unloaded region L are connected by the inner groove 7. On the other hand, an outer groove 8 of the turning groove 6 is formed in the end cap 3 in an arc shape. The outer groove 8 of the turning groove 6 projects from the joint surface of the end cap 3 with the bearing body 2 and is fitted into the linear groove 5 of the bearing body 2 to join the end cap 3 to a predetermined position. A tongue-shaped projection 9 is formed to scoop up the bearing ball b to accelerate the turning. The protrusion 9 is
The outside has a shape that closely engages with the groove inner peripheral surface of the straight groove 5,
On the other hand, the inner side is curved with the radius of curvature of the outer groove 8 of the turning groove 6 and has a shape that is pointed toward the tip (see FIG. 2).

In the linear ball bearing 1 as described above, at least the bearing body 2 or the end cap 3
Can be made of synthetic resin, that is, engineering plastic. Further, the bearing body 2 or the end cap 3 may be made of ceramics.

Linear ball bearing 1 according to the present invention
Since the above is configured as described above, it becomes easy to position and join the end cap 3 to the bearing main body 2 at a predetermined position. At this time, the tongue-shaped projection 9 has a shape in which the outer side is closely engaged with the groove inner peripheral surface of the linear groove 5 and has a shape pointed toward the tip, so that a step generated on the joint surface can be suppressed. . In this way, the straight groove 5 of the bearing body 2
By inserting the projection 9 into the groove, it is possible to easily join, and by joining, the inner groove 7 of the turning groove 6 on the side of the straight groove 5 and the outer groove 8 of the turning groove 6 are combined to form the turning groove 6. Thus, the infinite circulation groove 4 is completed.

At the joint of the swivel groove 6, the protrusion 9
Since the inner side of the groove bears the inner peripheral surface of the groove and has the arc shape of the outer groove 8 of the turning groove 6, the groove moves from a straight line to the turning portion without any step, and the influence of the joint surface is minimized. When the bearing ball b is running, the bearing ball b is swirled, and smooth running of the bearing ball b is achieved.
Since the structure is such that the end cap 3 is simply joined to the bearing body 2, the assembly manufacturing process can be simplified. Further, since the linear ball bearing 1 can be formed of engineering plastic or ceramics, the manufacturing cost can be suppressed.

Although the linear ball bearing 1 according to the present invention has been described with reference to one embodiment, it may be implemented as a ball spline bearing (not shown). In this case, although not shown, the spline formed on the guide shaft side and the groove exposed on the inner wall of the bearing body 2
The linear groove 5 in the load region P is used. The structure and operation of the ball spline bearing are the same, and the description thereof is omitted.

[0011]

As described above, according to the present invention, it becomes easy to position and join the end cap to the bearing body at a predetermined position. At that time, the tongue-like protrusions promote the turning of the ball when the ball travels from the straight groove to the turning groove, so that the influence of the joint surface can be suppressed as much as possible, and the circulation of the ball is not obstructed and smooth. Circulation is possible.
It should be noted that since the structure is such that only the end cap is joined to the bearing body, the assembly manufacturing process can be simplified, and since it is made of synthetic resin or ceramics,
Manufacturing cost can be suppressed.

[0012]

[Brief description of drawings]

FIG. 1 is an external perspective view showing the assembled structure of an embodiment of a linear ball bearing according to the present invention.

2 is a perspective explanatory view showing an infinite circulation groove of the linear ball bearing shown in FIG. 1 and a joint structure of a bearing body and an end cap.

[Explanation of symbols]

 1 linear ball bearing 2 bearing body 3 end cap 4 infinite circulation groove 5 straight groove 6 swivel groove 7 inner groove 8 outer groove 9 protrusion b bearing ball

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[Procedure amendment]

[Submission date] October 4, 1994

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 2

[Correction method] Change

[Correction content]

[Fig. 2]

Claims (3)

[Claims] 1. A bearing main body inner wall having a hollow bearing main body and end caps joined to both ends of the bearing main body, wherein the bearing main body is provided with straight grooves forming infinite circulation grooves of a large number of bearing balls. While forming a load region by being formed at a position exposed from the inside, a no-load region is formed by penetrating the inside of the bearing body wall, and an inner groove forming a swirl groove is formed at both ends of the bearing body. Then, the inner groove connects the linear grooves of the loaded region and the unloaded region, and the end cap is formed with an outer groove that constitutes a swivel groove, and the swivel groove is formed on the joint surface of the end cap with the bearing body. A linear ball bearing that is provided with a tongue-shaped projection that fits into the linear groove of the bearing main body to join the end cap at a predetermined position, and scoops up the bearing ball to facilitate turning at the outer groove end of the Ng. 2. A linear ball bearing, wherein the bearing main body and / or the end cap according to claim 1 is made of synthetic resin. 3. A linear ball bearing, wherein the bearing main body and / or the end cap according to claim 1 is made of ceramics.