JP2543313Y2 - Linear motion rolling guide bearing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a rolling element non-circulating type linear rolling used in a feed table device or the like for supporting a moving table so as to be linearly movable with respect to a bed. It relates to improvement of guide bearings.

[Prior Art] As a non-circulation type linear motion rolling guide bearing,
Fig. The one shown in FIG. 6 is known. In this device, one guide rail 1 is fixed to the bed 2 side, and the other guide rail 3 is fixed to the moving table 4 side, and a number of rollers 5 are held between the rails 1 and 3 by a holder 6. Has been interposed. By the rolling of the rollers 5, the moving table 4 is smoothly and linearly moved with respect to the bed 2 via the two guide rails 1 and 3. With the movement of the guide rail 3 fixed to the moving table 4 side, the retainer 6 moves in the same direction together with a large number of rollers 5. 7 is a stopper. The moving distance of the retainer 6 at that time is half of the moving stroke of the guide rail 3. Therefore, the length of the retainer 6 is (the length of the guide rail 3) − so that the retainer 6 does not come off the rail.
(Rail stroke / 2).

Note that the roller 5 in FIGS.
Although it is a cross roller type that crosses at an angle of °, a linear roller type in which the axes of the rollers are parallel is also known.

[Problems to be solved by the invention]

If the guide rails 1 and 3 have poor parallelism due to mounting errors,
The preload applied to the roller 5 becomes uneven, and the moving table 4
A difference occurs in the resistance of the reciprocating movement of Further, when the moving speed of the moving table 4 is different between going and returning, or when accelerating or decelerating while moving, a difference occurs in the magnitude of inertia. If the preload is uneven or the inertia is different, the relative positions of the guide rails 1 and 3 and the retainer 6 are slightly shifted while the moving table 4 repeats the reciprocating motion. Come. However, since the space between the guide rails 1, 3 and the roller 5 is not restrained in the longitudinal direction of the guide rails 1, 3, the phenomenon that the retainer 6 eventually comes off from the guide rails 1, 3 (micro (Slip phenomenon) occurs.

Conventionally, in order to prevent the micro-slip phenomenon, rack teeth are formed on the guide rails 1 and 3 and teeth such as pinions are formed on the outer periphery of the roller 5 so that the two mesh with each other. Means have been taken to correct the movements. However, these conventional micro-slip prevention means have the problems that the structure is complicated and the cost is increased, and that each part is excessively restrained.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to prevent the micro-slip by simple means without complicating the structure and increasing the cost without causing a large-scale change in the structure of each member.

[Means for solving the problem]

According to the present invention, two parallel guide rails each having a V-shaped cross section extending in the axial direction facing each other and relatively moving in the axial direction are held by a retainer between the two guide rails. A linear motion rolling guide bearing having a rolling element that rolls on a V-shaped raceway surface, at least one of the guide rails is slightly inclined toward the end at the end of the raceway surface to reduce the opening width of the raceway surface. An inclined surface that is gradually reduced is formed.

[Action]

When the rolling element at the end of the cage reaches the inclined surface at the end of the other guide rail due to the movement of one guide rail, the component of the radial load applied to the contact point between the rolling element and the inclined surface due to the slope action. Occurs in the direction opposite to the direction of movement of the cage.
Therefore, the cage is prevented from moving due to slip,
It is difficult to come off the guide rail.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same or corresponding parts as those in the related art are denoted by the same reference numerals.

FIG. 1 is a plan view of a guide rail raceway surface, FIG. 2 is a cross-sectional view of a set of linear motion rolling guide bearings, and FIG. 3 is III in FIG.
FIG. 3 is a sectional view taken along line III. One guide rail 1 (fixed side) of this embodiment has 90 ° at both ends in the length direction.
The track surface 11 of the grooved rail is slightly inclined toward the tip, and is provided with an inclined surface 12 that gradually reduces the opening width of the V-shaped track surface 11. The degree of inclination is preferably such that the maximum opening width B−the minimum minimum opening width A = 5 to 10 μm and the inclined surface length C = about 10 to 20 mm in FIG.

Track surface 11 of the other opposing guide rail 3 (moving side)
May be the same as before.

The two sets of linear motion rolling guide bearings 10, 1 thus formed
Numerals 0 are symmetrically attached to the bed 2 and the moving table 4 by bolts, as shown in FIG. 4, for example. Reference numeral 15 denotes a lateral push bolt.

Now, when the moving table 4 receiving the load F moves and the end of the moving-side guide rail 3 exceeds the end of the fixed-side guide rail 1 by about a half of a predetermined stroke, the cage that has moved together. The endmost roller 5 in 6 rests on the inclined surface 12 of the guide rail 1 as shown in FIG. Then, due to the slope action, the component force of the load applied to the contact point P of the roller 5 is opposite to the traveling direction of the roller 5 (arrow f).
And the roller 5 and the retainer 6 are restrained from proceeding further. This makes it difficult for the retainer 6 to come off the guide rail 1.

In this case, the end rollers 5 of the left and right guide bearings 10, 10 are
Each of the guide rails 3 on the moving side tries to be pushed outward, but since the guide rails 3 are arranged symmetrically, the outward force acting on the load roller 5 is offset, and the center of the moving table 4 is misaligned. Does not occur.

In the above embodiment, the inclined surface 12 at the end of the guide rail is provided on the guide rail 1 on the fixed side.
May be provided together. Further, it may be provided only on the guide rail 3 on the moving side.

Further, the case where the rolling element is a roll has been described, but a ball may be used.

[Effect of the invention]

As described above, according to the present invention, a simple means of providing a slight inclined surface at the end of the raceway surface of the guide rail so as to gradually reduce the opening width of the raceway surface toward the end is conventionally provided. Microslip, for which complicated measures had to be taken, can be easily prevented.

[Brief description of the drawings]

1 is a plan view of a main part of a guide rail according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view of a linear motion rolling guide bearing using the guide rail of FIG. 1, and FIG. 3 is FIG. FIG. 4 is a cross-sectional view of the feed table device equipped with the linear motion rolling guide bearing of FIG. 2, FIG. 5 is a perspective view of a conventional linear motion rolling guide bearing, and FIG. Is a half sectional view of the mounted state. In the figure, 1, 3 are guide rails, 5 is rolling elements, 6 is a cage, 10
Is a linear motion rolling guide bearing, 11 is a guide rail raceway surface, and 12 is its inclined surface.

Claims (1)

(57) [Scope of request for utility model registration] 1. Two parallel guide rails each having a V-shaped cross section extending in the opposite axial direction and moving relative to each other in the axial direction, and said guide rail being held by a retainer between the two guide rails. A linear motion rolling guide bearing comprising a rolling element that rolls on a V-shaped raceway surface, wherein at least one of the guide rails has an end portion of the raceway surface slightly inclined toward the tip and an opening width of the raceway surface. A linear motion rolling guide bearing, characterized in that an inclined surface is formed to gradually reduce the diameter.