JPH0325650B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a linear motion bearing used in slide tables of machine tools, other measuring instruments, slide parts of press machines, and the like.

B. Prior art In general, in mechanical devices that perform linear motion such as slide tables of machine tools, other measuring instruments, sliding parts of press machines, etc., the sliding stroke can be infinitely extended, and the linear motion of ball circulation type Often uses kinematic bearings.

As shown in FIGS. 1 to 3, the conventional structure of the above-mentioned ball circulation type linear motion bearing has rolling grooves 2 formed on the top and both sides of a long track 1 having a rectangular cross section. A sliding groove 2 formed in the longitudinal direction and having a U-shaped cross section straddles the track 1, and a rolling groove 2 of the track 1 on the inner peripheral surface of the slide 3 facing the track 1. A rolling groove 4, which together with this rolling groove 2 constitutes a ball rolling part
is formed in the longitudinal direction, and a return hole 5 of a ball return portion Y whose both ends are open at the end surface is formed in the adjacent part separated from the rolling groove 4 by a predetermined distance.
A lid 6 is fixed to both end surfaces of the sliding body 3, and the ball rolling portion
A U-shaped groove 7 of a ball reversing part Z is formed which communicates between the ball rolling part X, the ball returning part Y and the ball reversing part Z.
A retainer 8 is installed in each ball circulation path in part.
It accommodates a large number of balls 9 held in.

By the way, in the above-mentioned conventional ball circulation type linear motion bearing, the ball reversing part Z that communicates between the ball rolling part X and the ball returning part Y is the fourth
As shown in the figures to FIG. 6, a core fitting groove 10 is formed in the U-shaped groove 7 of the lid body 6 so as to be orthogonal to the U-shaped groove 7, and the core fitting groove 10 has a circular cross section. It is constructed by fitting arc-shaped (semi-cylindrical) inverted cores 11 into each other.

Therefore, it is necessary to machine a core fitting groove 10 in each U-shaped groove 7 of the lid body 6 and fit the inverted core 11 into each groove, which makes it troublesome to assemble the inverted cores 11. At the same time, there is a drawback that the combination of the reversing cores 11 tends to be slightly misaligned, making it difficult for the balls 9 to roll smoothly.

In addition, since the linear motion bearing does not have a contact angle with the balls 9 in the ball rolling portion X, it is difficult to receive a large load from the upward load of the sliding body 3, and play may occur. There are drawbacks to doing so.

C. Purpose of the Invention The present invention aims to provide a linear motion bearing that is easy to manufacture, allows balls to roll smoothly, and has an increased load capacity.

D. Structure of the Invention [Means for Solving the Problems] The present invention includes a track base in which two rows of rolling grooves are formed in the longitudinal direction on the top surface and one row on each side surface, and the track is formed in a U-shape in cross section. Rolling grooves corresponding to the rolling grooves of the way are formed in the longitudinal direction on the upper surface of the inner periphery and both sides of the inner periphery, and both ends are formed on the end surface at an adjacent part separated from these rolling grooves by a predetermined distance. A sliding body in which an opening ball return hole is formed, and a U-shaped recess with an arcuate cross section is formed around the opening on the inner end face corresponding to the end face of the sliding body, and the upper and both ends of this recess are formed. a lid body formed with an inversion groove forming the outer diameter side of an arcuate tubular ball inversion path that corresponds to the rolling groove and ball return hole of the sliding body; an inverted core body having an inverted groove forming the inner diameter side of an arcuate tubular ball inverted path corresponding to the inverted groove of the cover plate on the upper and both sides thereof, and a rolling groove of the track base. a sealing member having a seal lip on its inner circumferential surface corresponding to the ball, and balls arranged and held in the rolling groove and ball return hole of the sliding body and the ball reversal path, and the ball is arranged and held in the recess of the lid body. The core body is fitted, and an arcuate tubular ball reversal path is formed by mutual reversal grooves on the abutting surfaces, and this lid body is fixed to both end surfaces of the sliding body, and the outer side of the lid body The sealing member is attached to the end face, and the sliding body is slidably straddled over the way via the balls, and the rolling grooves on both sides of the way and the sliding body opposite thereto are connected to each other. The balls arranged between the rolling grooves on both sides of the inner circumference have a contact angle to support the upward load of the sliding body.

[Effect]

The balls roll under load between the rolling grooves on both sides of the wayway and the corresponding rolling grooves on both sides of the inner circumference of the sliding body, and there is no load in the ball return hole running inside the sliding body. roll in the state. The ball reversing paths located at both ends of the sliding body connect the rolling grooves and the ball return holes to enable circulation of the balls. This ball reversal path is configured in an arcuate tube shape with the reversal groove formed in the lid body and the reversal groove formed in the reversible core body, so the ball moves as if it were rolling inside a pipe. , the ball can be smoothly reversed and circulated from the rolling groove to the ball return hole or vice versa. Moreover, it has a gate-shaped shape (U-shape).
By simply fitting the reversing core body into the recess of the lid body having the same shape, an arcuate tubular ball reversing path is formed on the mating surfaces of the two. Therefore, there is almost no room for misalignment, unlike when inserting a core with a semicircular cross section as in the conventional case.

In the part of the ball circulation path that constitutes the load area, a contact angle is given to the balls arranged between the rolling grooves of the wayway and the rolling grooves of the sliding body to support the upward load of the sliding body. Can be done. Various structures for imparting a contact angle can be considered, but in this invention, since the positions of the rolling grooves on the vertical planes facing each other in parallel are simply shifted, the rolling grooves are formed on both sides of the inner circumference of the sliding body. It is extremely easy to process
High accuracy can therefore also be obtained.

E. Embodiment FIGS. 7 to 12 show an example of a rolling element circulation type linear motion bearing according to the present invention.
In this drawing, reference numeral 12 denotes a long track with a rectangular cross section, and rolling grooves 14a, 1 with an arcuate cross section, in which two rows of balls 13 roll on the top surface and one row each on both sides.
4b, 14c, and 14d are formed in the longitudinal direction. As shown in FIGS. 7, 11, and 12, reference numeral 15 denotes a sliding body having a U-shaped cross section and extending over the track 12. The slide body 15 has a U-shaped cross section that extends over the track 12. Rolling grooves 14a, 14b of platform 12
rolling grooves 16a each having an arc-shaped cross section,
16b is formed in the longitudinal direction, and a 12th groove is formed on both inner circumferential sides facing both sides of the wayway 12 between the rolling grooves 14c and 14d of the wayway 12.
As shown in the figure, rolling grooves 16c and 16d each having an arcuate cross section are formed in the longitudinal direction so that the ball 13 is contacted and supported with a contact angle α of about 30 degrees, and these rolling grooves 16a, 16b, 16c, 1
Ball return holes 17a, 17b, 17 with open ends at both ends are located adjacent to 6d at a predetermined distance.
c, 17d into the corresponding rolling grooves 16a, 16b, 16
It is drilled parallel to c and 16d. 18 is a gate-shaped lid that covers the front and rear end surfaces of the sliding body 15, and as shown in FIGS. 13 to 16, the sliding body 1
A recess 19 having an arcuate cross section is formed around the opening of the inner end face opposite to the end face of 5, and a recess 19 having an arcuate cross section and an inverted portal shape as shown in FIGS. 17 to 20 is formed in the recess 19. The child body 20 is fitted, and inverted grooves 21a, 21b, 21c, 21d are formed on the abutting surfaces of the two.
and 22a, 22b, 22c, and 22d each having an arcuate cross section to form the rolling groove 14 of the track 12.
a, 14b, 14c, 14d, rolling grooves 16a, 16b, 16c, 16d of the sliding body 15 and the ball return hole 17 of the sliding body 15 facing these.
ball reversal paths 23a, 23b, 23c, 23d that communicate between
It consists of Each ball reversal path 23a to 23d
has an arcuate tubular shape, and its outer diameter side is constituted by the inverted grooves 21a to 21d of the lid body 18, and its inner diameter side is constituted by the inverted grooves 22a to 22d of the inverted core body 20. 13, 15 and 1 on the outer end surface of the lid body 18.
As shown in FIG. 6, a flat notch 24 is formed, and a locking groove 25 is formed on the inner peripheral edge facing the track 12, as shown in FIGS. 14 to 16. 26, as shown in FIG. 12, connects the balls 13, 13, .
6c, 16d, the cage has a predetermined length and a U-shaped cross section, and has rolling grooves 14a, 14b, Forming slits 27a, 27b, 27c, 27d corresponding to the balls 14c, 14d at intervals such that the balls 13, 13... do not fall out,
These slits 27a, 27b, 27c, 27d
As shown in FIGS. 21, 22, and 24, both ends of the ball 13 are tapered so that the ball 13 is guided in the rotational direction rather than in the linear direction.

Reference numeral 28 denotes a sealing member made of rubber, soft synthetic resin, etc., and as shown in FIGS.
Convex seal lips 29a, 29b, 29c, 29 in an arc shape corresponding to b, 14c, 14d
d. Reference numeral 30 denotes a seal presser plate that is fitted into the notch 24 of the lid 18, and the seal member 28 is fitted onto the inner peripheral surface as shown in FIGS. 25 to 28. Then, as shown in FIG. 9, this seal presser plate 30 is attached to the notch 24 of the lid body 18, and at the same time, the seal member 28 is held between the lid body 18 and the seal presser plate 30. Reference numeral 31 designates a suitable number of fixing holes formed along the longitudinal direction of the track 12 as shown in FIG. 8, and these holes are used to properly fix the track 12. 32a,
Reference numerals 32b, 32c, and 32d are mounting holes formed in the upper surface of the sliding body 15 as shown in FIGS. 7 to 11, and are used to mount a mechanical device (not shown) for performing linear motion. 33a, 33b,
33c and 33d are the lids 1 on the front and rear end surfaces of the sliding body 15.
8 and the seal presser plate 30 as shown in FIGS. 7 and 9 to 11.

Each part of the linear motion bearing of the present invention is constructed as described above, and its operation will be explained next.

When the sliding body 15 on the track 12 is moved by an appropriate means, the rolling grooves 14a, 14b,
14c, 14d and the rolling groove 16a of the sliding body 15,
The sliding body 15 smoothly linearly moves along the track 12 in a predetermined direction via the balls 13, 13, . . . held between the balls 16b, 16c, 16d. At this time, the rolling grooves 14a, 14b, 14c, 14d of the way base 12 and the sliding body 15
The balls 13, 13, which are held between the rolling grooves 16a, 16b, 16c, 16d...
The slits 27a, 27b, 27 of the retainer 26
It rolls while being guided by c and 27d, and the cage 26
Each slit 27a, 27b, 27c, 27d is guided so as to be scooped up in the rotational direction from the linear direction by the tapered portion at one end of the slit 27a, 27b, 27c, 27d, and the rolling grooves 21a, 21b, 21c,
Ball reversal paths 23a, 23b, 23 formed by 21d and 22a, 22b, 22c, 22d
The balls 13, 13... roll through c, 23d and reach the ball return holes 17a, 17b, 17c,
17d and ball return holes 17a, 17
b, 17c, and 17d, and the other lid body 18 and the rolling grooves 21a, 2 of the inverted core body 20 are formed at the terminal end.
1b, 21c, 21d and 22a, 22b, 22
Ball reversal path 23a formed by c, 22d,
From 23b, 23c, 23d to the rolling grooves 14a, 14b, 14c, 14d of the way base 12 and the sliding body 15
It is fed again between the rolling grooves 16a, 16b, 16c, and 16d to circulate.

F. Effects of the Invention In the linear motion bearing of the present invention, four ball reversal paths 23a, 23b, 23c, and 23d can be formed simultaneously by simply fitting the integral reversing core body 20 into the lid body 18. Moreover, since each ball reversing path is configured in an arcuate tube shape with the reversing groove of the lid body and the reversing groove of the reversing core body, it is possible to easily and precisely combine the balls, and there is no misalignment. Smooth rolling is performed and the sliding body 15 moves smoothly. As described above, according to the present invention, due to the configuration of the ball reversing path, assembly is extremely easy and accuracy can be achieved. This allows the ball to roll smoothly and the sliding body to move smoothly with a small amount of force.
It can be widely applied to various mechanical devices that require linear motion. In addition, the positions of the rolling grooves on both sides of the way and the corresponding rolling grooves of the sliding body are slightly shifted so that the balls supported in contact between them have a contact angle of approximately 30°. from,
It is possible to increase the load capacity of the sliding body against upward loads with simple machining and high precision. Furthermore, the seal member provided on the outer end surface of the lid body allows
Not only does it provide a dustproof effect, but it also simplifies lubrication.

[Brief explanation of the drawing]

Figures 1 to 3 show a conventional linear motion bearing, with Figure 1 being a partially cutaway front view, Figure 2 being a partially cutaway plan view, and Figure 3 being taken along line A-A in Figure 1. FIG. FIG. 4 is a side view of the lid of a conventional linear motion bearing, FIG. 5 is a sectional view taken along the line B--B in FIG. 4, and FIG. 6 is a perspective view of the reversible core. 7th
Figures 12 to 12 show an example of the linear motion bearing of the present invention, and Figure 7 is a perspective view showing an assembled state;
Fig. 8 is a perspective view showing the disassembled state, Fig. 9 is a partially cutaway front view, Fig. 10 is a plan view, Fig. 11 is a side view, and Fig. 12 is a view taken along line C-C in Fig. 9. FIG. 13 to 16 show the lid of the linear motion bearing of the present invention, in which FIG. 13 is a front view, FIG. 14 is a back view, FIG. 15 is a bottom view, and
FIG. 6 is a sectional view taken along the line DD in FIG. 14. 17 to 20 show the inverted core body of the linear motion bearing of the present invention. FIG. 17 is a front view, FIG. 18 is a top view, FIG. 19 is a bottom view, and FIG.
Figure 0 is a side view. 21 to 24 show the cage of the linear motion bearing of the present invention, in which FIG. 21 is a front view, FIG. 22 is a plan view, FIG. 23 is a partially sectional side view, and FIG. The figure is E in Figure 23.
- It is a sectional view in the E line. Figures 25 to 2
8 shows the assembled state of the seal member and the seal presser plate, FIG. 25 is a front view, FIG. 26 is a plan view, FIG. 27 is a side view, and FIG. It is a sectional view in the F line. 12... Orbital platform, 13... Ball, 14a, 1
4b, 14c, 14d...Rolling groove, 15...Sliding body, 16a, 16b, 16c, 16d...Rolling groove, 17a, 17b, 17c, 17d...Ball return hole, 18...Lid body, 20 ...inverted core body,
21a, 21b, 21c, 21d, 22a, 22
b, 22c, 22d...Rolling groove, 23a, 23
b, 23c, 23d...Ball reversal path, 26...
Cage, 27a, 27b, 27c, 27d...Slit, 28...Seal member, 29a, 29b,
29c, 29d... Seal lip, 30... Seal press plate, 33a, 33b, 33c, 33d...
Mounting bolts.

Claims (1)

[Claims] 1. A wayway with two rows of rolling grooves formed in the longitudinal direction on the top surface and one row each on both sides, and a raceway formed in a U-shape in cross section, with rolling grooves of the wayway formed on the upper surface of the inner periphery and on both inner periphery sides. A sliding body in which rolling grooves corresponding to the grooves are formed in the longitudinal direction, and a ball return hole with both ends opening at the end surface in an adjacent part separated from the rolling grooves by a predetermined distance; A recess with an arcuate cross section is formed in a U-shape around the opening of the inner end face corresponding to the end face, and the upper part and both ends of the recess correspond to the rolling groove and ball return hole of the sliding body.
A lid body with an inversion groove forming the outer diameter side of the arc-shaped tubular ball reversal path, and a lid body formed in a U-shape with an arcuate cross section, the upper and both sides of which correspond to the inversion grooves of the lid body. an inversion core body having an inversion groove formed on the inner diameter side of an arcuate tubular ball inversion path; a seal member having a seal lip on an inner circumferential surface corresponding to the rolling groove of the track; The balls are arranged and held in the rolling groove of the sliding body, the ball return hole, and the ball reversal path, and the reversible core body is fitted into the recess of the lid body, and the reversals of each other are formed on the abutting surfaces. The grooves constitute an arcuate tubular ball reversal path, the lid is fixed to both end surfaces of the sliding body, the sealing member is attached to the outer end of the lid, and the sliding body is fixed to the sliding body. A ball that is slidably straddled over the wayway via the ball and is arranged between rolling grooves on both sides of the wayway and rolling grooves on both sides of the inner periphery of the opposing sliding body. A linear motion bearing characterized in that it has a contact angle to support an upward load of a sliding member.