JPS62141308A - Bearing for rectilinear motion - Google Patents

Abstract

PURPOSE:To increase up and down moment load bearing capacity by providing two ball circulating paths on the upper surface of a raceway table and two upper and lower ball circulating paths on both side surface thereof. CONSTITUTION:An upper surface ball groove 13 is formed on the upper surface both side portions of a raceway table 11, and upper and lower ball grooves 15, 16 are formed on both side surfaces. On the other hand, a sliding table 12 comprises a support 18 and both side walls 19. A turn groove opposite to the ball groove 13 and two load ball grooves 20 connected to a no-load ball hole 22 are formed on the lower surface of the support 18. Two load ball grooves 23, 24 which are opposite to the ball grooves 15, 16 and communicate with no-load ball holes 27, 28 through the turn groove are formed on the inner surface of the side wall 19. In this arrangement, contact angles of lines of balls 35, 36, 37 and ball grooves 13, 15, 16 are alpha=90 deg., and beta=45 deg.. Thus, the capacity of bearing vertical and sideways load can be increased to lessen vibration and attain high rigidity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a linear motion bearing, a so-called linear bearing, and particularly to a linear motion bearing suitable for heavy loads.

[Conventional technology]

Various types of linear motion bearings have been known in the past, and a typical conventional example in relation to the invention of this application is shown in FIG. 6 or 7.

All of these linear motion bearings have a sliding base 2 mounted on a way base 1, and load ball grooves 4 are formed on the surface of the sliding base 2 facing the ball rolling grooves 3 of the way base 1. A plurality of ball circulation paths 6 are provided in which a non-load ball hole 5 provided through the moving table 2 is communicated with both ends of the load ball groove 4, and balls are stored in each circulation path 6 to form a ball row 7. It was formed.

In the case of Fig. 6, four rows of ball rows 7 are provided, and the two rows on the top surface are formed to have a contact angle of 90 degrees, and the two rows on both sides are formed to have a contact angle of 30 degrees, and the loads from the side and bottom surfaces are It is supported by ball rows 7 arranged on each side.

In addition, in the case of FIG. 7, four rows of balls 7 are provided, and each ball row 7 on the top and bottom surfaces is formed to have a contact angle of 45 degrees, so that the load from the top surface is transferred to the balls in the two rows on the top surface. The load from the side is supported by the ball rows 7 on one of the upper surfaces and the ball rows 7 on one of the lower surfaces.
The load from the bottom surface is supported by two rows of balls 7 on the bottom surface.
It is now supported by

[Problem that the invention seeks to solve]

In general, linear motion bearings are often used with loads applied from the top surface, but in all of the conventional examples mentioned above, the load from the top surface is borne only by two rows of balls, so the load is There is a certain limit to the ability to bear the burden.

Therefore, this invention increases the load-bearing capacity by arranging the rows of balls arranged on the side of the track so as to bear not only the load in the lateral direction but also the load in the vertical direction, and the capacity to bear the moment load. The purpose is to increase the number of people.

[Means for solving problems]

In this invention, ball circulation paths are provided in two rows on the top surface of the track and two rows above and below both side surfaces, for a total of 6 rows, and the contact lines of the balls in the upper and lower load ball grooves on both side surfaces are formed so as to intersect obliquely with the horizontal line. The structure is as follows.

[Effect]

The load from the top is supported by two ball rows in the ball circulation path on the top surface and two ball rows on both sides, a total of four ball rows. Loads from the sides are applied to the top and bottom of each side.
Due to the row of balls in the row, the load from the bottom is reduced to two on both sides.
Supported by rows of balls in rows.

C Embodiment] Hereinafter, embodiments of the present invention will be described based on FIGS. 1 to 4.

The basic structure of the linear motion bearing of the embodiment is a combination of a track base 11 of a required length and a sliding base 12 mounted thereon.

The track base 11 has a rectangular cross-sectional shape as a whole, and has upper surface ball grooves 13 formed on both sides of its upper surface. Further, an upper ball groove 15 and a lower ball 1ll16 are formed on both side surfaces. Further, mounting holes 17 are formed in the track base 11 at regular intervals, passing through both the upper and lower surfaces thereof.

The slide table 12 consists of a support body 18 and both side walls 19 formed on both sides of the lower surface thereof, and is straddled on the track base 11 through a space formed between the lower surface of the support body 18 and both side walls 19. installed in the state.

The upper surface ball groove 13 of the track base 11 is provided on the lower surface of the support body 18.
Two rows of load ball grooves 20 facing each other are formed.

Further, both ends of each load ball groove 20 are continuous with turn grooves 21 (see FIG. 4) formed on both end surfaces of the support body 18, and the turn grooves 21 are in a penetrating state between the both end surfaces of the support body 18. It communicates with a no-load ball hole 22 provided in the.

Also on the inner surface of the side wall 19, the upper ball groove 15 of the track base 11,
Two rows of load ball grooves 23 facing the lower ball grooves 16.
24 are formed, and these are turn grooves 25 and 26, respectively.
It communicates with the unloaded ball holes 27 and 28 through.

The lid member 29 attached to both end faces of the sliding table 12 is
The entire support body 18 and both side walls 19 are formed in a downward C-shape so as to cover their end surfaces, and grooves 30.3L are formed on the inner surface thereof, facing each of the turns 1JI2L25.26.
32 is formed.

Two rows of endless ball rows 35 are constructed by interposing cages 33 and 34 between the upper surface of the track 11 and the lower surface of the support body 18 and on both side surfaces and filling them with balls 41. Similar two rows of upper and lower ball rows 36 on the surface
．． 37 are constructed.

The retainer 33 interposed on the upper surface of the track base 11 has two rows of ball retainers 'a38, and both end portions of the retainer 33 match with the lower part of the groove 30 formed on the inner surface of the lid member 29 (see FIG. 3). reference). The retainer 34 also has ball support surfaces 40 on its upper and lower sides.

Among the above ball rows 35, 36, 37, ball groove 13.
The ball 41 on 15.16 bears the load, and the other parts are unloaded.

In the two ball rows 35 formed on the top surface, the angle α of the contact line of the balls 41 in the top ball groove 13 with respect to the horizontal line is set to 90 degrees. In addition, in the ball rows 36 and 37 formed on the side surface, the angle β of the contact line of the balls 41 in the upper ball groove 15 and the lower ball groove 16 with respect to the horizontal line is each set to 45 degrees, and the intersection of both contact lines is set to 45 degrees. is located outside the track 11.

In addition, in the figure, 42 is a sealing material, and 43 is a grease nipple.

It is desirable to apply a certain preload to the balls 41 in each of the ball rows 35, 36, 37 in each load ball groove 20 by appropriately selecting the diameter thereof.

These preload diagrams are shown in FIG. In FIG. 5, the horizontal axis shows the apparent preload amount δ (difference between the diameter of the ball and the distance between the ball grooves sandwiching it) of the upper ball row 35, the left vertical axis shows the vertical preload amount δ′, and the right vertical axis shows the preload amount δ′ in the vertical direction. Vertical preload P (ball 1
(per piece). Graphs δ′1, δ″2, δ shown by solid lines
'3 are balls 41 of ball rows 35, 36, and 37, respectively.
The graphs P+ and Pg shown by broken lines indicate the preload amount δ′ of
, P3 indicate ball loads P for giving displacements of δ'1, δ'2, and δ'3, respectively. In addition, ball row 36.3
The amount of preload in the vertical direction between the balls 41 of No. 7 is 20 μm.

The contact angle α of the balls 41 in the ball row 35 is 90 degrees, and the contact angle β of the balls 41 in the ball rows 36 and 37 is 45 degrees.

As is clear from the above preload diagram, as δ' increases (because the sliding table 12 tends to float), δ'2 increases, while δ- decreases. Paying attention to the fact that the balls 41 of the upper surface ball row 35 and the balls 41 of the lower side ball row 37 receive the load from the top surface at the same time, this point A is the intersection of the ball load curves PI and P3. The apparent preload amount δ1 of the ball row 35 corresponding to is Xl
Therefore, δ'2 and δ' corresponding to this become Y2 and Y3.

In Figure 5, X+ #13/' m, Y2 + Y
Since 3=40pm, X+: Y2 + Y3
= 1:3. That is, two rows of balls 4 on the top surface
By setting the apparent preload amount δ of 1 and the total preload amount of the balls 41 in the four rows on both sides to approximately 1=3, the load from the top is transferred to the balls 41 in the two rows of balls 35 on the top surface and the balls 41 on both sides. It can be supported by the lower two rows of balls 37.

The embodiment of the present invention has the above configuration, and its operation will be explained next.

As described above, the load acting on the upper surface of the support body 18 is supported by a total of four ball rows 35 and 37, including two ball rows 35 on the upper surface and lower ball rows 37 on both sides.

Further, the load acting on the side surface is supported by two rows of balls 36 and 37 on one side surface, upper and lower, depending on the direction of the load. Further, the load acting on the lower surface in the lifting direction is supported by the upper two rows of balls 36 on both side surfaces.

Note that the contact angle α in the above embodiment may be changed around 90 degrees, and the contact angle β may be changed around 45 degrees depending on design conditions.

〔effect〕

As described above, the present invention is suitable as a heavy-load type linear motion bearing because the load from the top can be supported by four rows of balls. In addition, it has the effect of increasing the ability to bear loads from the side and being able to bear loads from the bottom (loads in the lifting direction).

Furthermore, compared to the case where there are four rows of balls, the amount of preload on each ball is smaller, and the impact when the balls enter the load ball grooves of the slide table is smaller. In addition, since the impact is borne by the remaining many balls, vibration is reduced and high rigidity is achieved.

[Brief explanation of drawings]

Fig. 1 is a partially omitted perspective view of the embodiment, Fig. 2 is a longitudinal sectional front view of the same, Fig. 3 is a longitudinal sectional side view of the same, Fig. 4 is an exploded perspective view showing a part of the same, and Fig. 5. is the graph related to preload, No. 6
7 and 7 are cross-sectional views of the conventional example. 11... Track platform, 12. Curved/sliding platform, 13...
Curved ball surface hole groove, 15... Side upper ball groove,
16... Four side lower ball grooves, 18... Surface support, 19
...Curved side wall, 20...Load ball groove, 21...
Output groove, 22... No-load ball hole, 23.
24...Load ball groove, 25.26...Curved turn groove, 27.28...No load ball hole, 2nd...
Curved/lid member, 3o, 31.32...Groove, 33.
34...Cage, 35.36.37...
- Ball row.

Claims (3)

[Claims] (1) A slider is mounted on the wayway, a loaded ball groove is formed on the surface of the slider facing the ball rolling groove of the wayway, and a non-load ball hole is provided through the slider. In a linear motion bearing in which a plurality of ball circulation paths are provided, each of which is connected to both ends of the load ball groove, and a ball is housed in each circulation path, the ball circulation paths are arranged in two rows on the upper surface of the track base.
A bearing for linear motion, characterized in that two rows are provided above and below on both sides, for a total of six rows, and the contact lines of balls in the upper and lower load ball grooves on both sides are formed obliquely to the horizontal line. (2) For linear motion according to claim 1, wherein the contact line is formed so as to obliquely intersect with the horizontal line, and the intersection of the contact lines is located outside the track base. bearing. (3) The contact angle of the two rows of balls on the top surface is set to 90 degrees, and the contact angle of the four rows of balls on both sides is set to 45 degrees, and the apparent preload amount of the former balls and the total preload amount of the latter balls are approximately 1 3. The linear motion bearing according to claim 1, wherein the linear motion bearing is set at a ratio of :3.