JPH065087B2 - How to adjust the clearance for linear sliding bearings - Google Patents

Description

The present invention relates to a linear sliding bearing that linearly guides a movable body to be slid in a sliding portion of a machine tool such as an NC machine or an industrial robot. In particular, it adjusts the pressurization of the ball that applies a load between the slide table and the raceway that make up the bearing, or adjusts the clearance of the linear sliding bearing for smooth rolling of the ball. Regarding the method.

[Conventional technology]

The linear sliding bearing generally includes a slide base having a recessed portion on the lower surface side and having a substantially inverted C-shaped cross section, and a raceway whose upper part is fitted in the recess of the slide base while maintaining a predetermined gap. The ball formed on the slide table has a large number of balls circulating in an endless track, and linear reciprocating motion along the track table while applying vertical and horizontal loads acting on the slide table with these balls. Is configured to guide.

In such a linear sliding bearing, it is required that it can be incorporated into a sliding portion of a general industrial machine with high accuracy, and that its positioning and repeatability are good and its life is long. In order to impart such characteristics, the distance between the load ball groove of the sliding table and the rolling groove of the track table on which the ball that loads the load rolls between the sliding table and the track table is set. It is important to set the ball in a negative state compared to the diameter of the ball, thereby applying pressure to the ball to increase the hit rate of all balls and to prevent hammering action and prying load etc. due to the moment of inertia when changing direction. It is important that each ball circulating in the ball endless track smoothly circulates from its unloaded region to its loaded region or from its loaded region to its unloaded region.

For this reason, conventionally, as a means for applying a pressure to the ball, ball selection fitting is performed in which the ball is selected and the diameters of the balls are aligned and fitted, or a split groove is formed in the sleeve portion of the sliding base. Bolts are used to adjust the clearance between the slide base and the raceway, and as a means for smooth ball circulation in the ball endless track, the load ball of the slide base is used. For example, so-called crowning is performed to widen both ends of the groove and narrow the middle part.

[Problems to be Solved by the Invention]

However, ball selection fitting, which is performed as a means for applying pressure to the balls, is a very troublesome work, and the ball selection fitting and clearance adjustment performed from the side of the slide base make the bearing a slide part of the machine. There is a problem that it is difficult to adjust the pressurizing force that acts on the ball according to the purpose of use of this bearing, and it is also necessary to perform crowning processing on the load ball groove of the slide base. There is a problem in that the work to be performed must be finished with high processing accuracy, which is a very troublesome work.

[Means for Solving the Problems]

The present invention has been made in view of such a point of view, and the ball diameter is selected to be larger than the distance between the load ball groove and the rolling groove that face each other. A pair of mounting surfaces are formed along the upper longitudinal direction, a mounting base is mounted on the pair of mounting surfaces by a plurality of fastening bolts, and the space between the upper surface of the horizontal portion and the lower surface of the mounting base is between the mounting surfaces. A gap adjusting press bolt is formed in the mounting base, which penetrates the mounting base and contacts the horizontal portion at an intermediate position between the pair of mounting surfaces. It is characterized in that it is moved to press the horizontal portion.

[Work]

According to such a technical means, the ball sandwiched between the load ball groove of the sliding base and the rolling groove of the raceway is preloaded from the beginning, but the above-mentioned gap adjusting pressure bolt is used. By rotating and pressing the horizontal portion of the slide base, the gap between the inner surface of each sleeve portion of the slide base and the outer surface of the raceway is widened, and the preload applied to the ball is reduced, and , This can be adjusted.

〔Example〕

Hereinafter, the method for adjusting the clearance of the linear sliding bearing according to the present invention will be specifically described with reference to the accompanying drawings.

1 to 5 show a linear sliding bearing B to which an embodiment of the method of the present invention is applied. This bearing B has a horizontal portion (5) and a pair of sleeve portions (6) hanging downward from both sides thereof, and is provided with a trapezoidal recess (7) on the lower surface side, and both sleeves are provided. Along with the longitudinal direction of the inner surface of the portion (6), there is a substantially semi-circular load ball groove (8) and the escape ball track (9) corresponding to each load ball groove (8).
Inside the recess (7) of the sliding base (1) having a trapezoidal upper part and a sliding base (1) having a substantially inverted C-shape in cross section, which is formed with an escape ball hole (9a). Rails (2) having a substantially semicircular rolling groove (10) corresponding to the load ball groove (8) and fitted together while maintaining a predetermined gap between them, and the sliding table (1 )
A guide groove (not shown) that is attached to both front and rear end surfaces and that forms an endless track of balls by communicating and connecting the ends of the load ball groove (8) and the escape ball hole (9a) to each other on the inner surface side. With a pair of lids (3), which circulate in the ball endless track, and the load ball groove (8) of the slide table (1) and the rolling groove of the track table (2).
It is composed of a large number of balls (4) that bear a load between it and (10).

On the upper surface of the horizontal part (5) of the sliding base (1), as shown in FIG.
As shown in FIG. 5, a pair of mounting surfaces (11) extending along the upper longitudinal direction of both sleeves (6) is formed, and mounting bases (11) are provided at both ends of each mounting surface (11). Mounting holes (14) into which fastening bolts (13) are screwed when mounting (12) are drilled, and each mounting surface (11) is attached to the upper surface of the horizontal part (5).
Between the above and the lower surface of the mounting base (12), a predetermined gap D
The concave surface (15) is formed so that

Further, the mounting base (12) has a pair of mounting surfaces formed on the upper surface of the horizontal portion (5) of the sliding base (1) so as to penetrate the mounting base (12).
Three gap adjusting pressure bolts (16) abutting the horizontal part (5) on the horizontal part center line 1 located in the middle of (11)
(Hereinafter, a pressing bolt) is screwed.

Further, the ball (4) is a slide base whose diameter faces each other.
It is selected to be larger than the distance between the load ball groove (8) in (1) and the rolling groove (10) in the way (2), and between the load ball groove (8) and rolling groove (10). Pre-load is applied when it is sandwiched between.

The reference numeral (18) in FIGS. 1 to 4 is a bed having a mounting reference surface (19) when fixing the raceway (2) of the bearing B to various mechanical devices, and FIGS. In FIG. 5, reference numeral (20) is a mounting bolt for fixing the lid body (3) to the front and rear end surfaces of the slide base (1), and in FIG.
Reference numeral (21) is a contact position indicating a position where the pressing bolts (16) and (16a) contact the upper surface of the horizontal portion (5) of the slide base (1).

Next, with respect to the bearing (B) according to this embodiment, an assembling procedure for various mechanical devices and a method for adjusting the clearance (d) between the slide table (1) and the track table (2) will be described. To do.

First, the bed (18) of various machines and equipment has its mounting reference surface (1
Fix the rail (2) to 9) and install the bearing B, then place the mounting base (12) on the mounting surface (11) formed on the upper surface of the horizontal part (5) of the sliding base (1). , Raise the height and tighten the fastening bolt (1
Connect by 3) and fix the mounting base (12). After assembling the bearing B in this way, while watching the sliding state of the bearing B, tighten the pressure bolts (16) from above the mounting base (12) to fix the horizontal portion (5) of the sliding base (1). ) A pressing force in the direction of arrow Y _{1 is applied to the} upper surface, and elastic deformation as shown by the chain double-dashed line in FIG. 6 is applied to this horizontal part (5), so that both sleeve parts (6) of the slide base (1) Widen the space between each sleeve of the slide (1)
(6) Set the initial gap d between the inner surface and the outer surface of the way (2) to d ₁
Spread to.

In this way, by applying elastic deformation as shown in FIG. 6 to the horizontal part (5) of the slide base (1), each sleeve part of the slide base (1)
(6) The distance between the loaded ball groove (8) formed on the inner surface and each rolling groove (10) formed on the outer surface of the raceway (2) is defined by the ball (4)
The diameter of each ball (4) rolling in the loaded ball groove (8) is reduced and the preload is adjusted to a predetermined value.

7 and 8 show a modified example of the linear sliding bearing B to which the method of the present invention is applied. The bearing B of FIG. 7 is a sliding base (a slide base) having a pair of bearing races (24). 1) is used, and in the bearing B of FIG. 8, the recess (7) on the lower surface side is formed in a substantially semicircular shape, and is formed along the inner surface of the recess (7). The loaded ball groove (8) is formed in a substantially semi-elliptical shape, and the escape ball track (9) is composed of a deep groove (9b) formed along the longitudinal direction of the inner surface of the recess (7). Further, a ball retainer (25) is provided on the inner surface of the recess (7), and two pairs of ball endless tracks are formed in cooperation with guide grooves provided on front and rear lids (not shown), In addition, the rail (2) has ridges (26) on both shoulders.
Is formed to form rolling grooves (10) on both side surfaces thereof, and the projection (26) is sandwiched by balls (4) circulating in the ball endless tracks of each pair.

Also in the bearing B of each of these modified examples, the sliding base (1) is fixed by the pressing bolt (16) in exactly the same manner as described above.
The gap d between the inner surface of each sleeve (6) and the outer surface of the track (2) can be widened to reduce the pressurization of each ball (4) in the load range and adjust this.

The arrangement and number of the fastening bolts (13) and the pressing bolts (16) are such that, if the pressing bolts can be rotated to widen the gap between the inner surface of each sleeve of the slide and the outer surface of the raceway, The present invention is not limited to the above embodiment.

〔The invention's effect〕

As described above, according to the clearance adjusting method for the linear sliding bearing of the present invention, the clearance adjusting pressing bolt is rotated to press the horizontal portion of the sliding base, and the sliding base is moved to the inner surface of each sleeve. Since the clearance between the raceway and the outer surface is widened, it is pre-applied to the ball by rotating the clearance adjusting pressure bolt from above the mounting base after incorporating the bearing into various mechanical devices. Preload can be adjusted by reducing the preload, which is extremely troublesome for selective fitting of balls and adjustment of the clearance from the side of the sliding base, which is a problem in terms of downsizing of mechanical equipment. No need to make adjustments.

[Brief description of drawings]

FIG. 1 is a front view showing an assembled state of a linear sliding bearing to which a clearance adjusting method according to an embodiment of the present invention is applied, FIG. 2 is a side view of FIG. 1, and FIG. 3 is FIG. Top view of the fourth
The drawing is a cross-sectional view taken along the line IV-IV in FIG. 3, FIG. 5 is a plan view of the bearing showing a state in which the mounting base is removed in FIG. 3, and FIG. 6 is a state in which the horizontal portion of the sliding base is elastically deformed. FIG. 7 and FIG. 8 are exaggeratedly illustrated front views, which are sectional views similar to FIG. 4 showing a modified example of the linear sliding bearing to which the method of the present invention is applied. [Explanation of symbols] B: Bearing (1): Sliding base (2): Track base (3): Lid (4): Ball (5): Horizontal part (6): Sleeve part (7): Recessed part (8) ): Load ball groove (9): Relief ball raceway (9a): Relief ball hole (9b): Deep groove (10): Rolling groove (11): Mounting surface (12): Mounting base (13): Fastening bolt ( 16): Gap adjusting pressure bolt l: Horizontal center line d: Gap D: Gap.

Claims (1)

[Claims] 1. A load ball having a horizontal portion and a pair of sleeve portions that hang downward from both sides thereof and having a recessed portion on the lower surface side, and the sleeve balls are provided with a load ball along the inner surface longitudinal direction thereof. A slide base having a substantially inverted C-shaped cross section having grooves and escape ball raceways corresponding to the respective load ball grooves and an upper part are fitted in the recesses of the slide base while maintaining a predetermined gap therebetween. At the same time, a raceway having rolling grooves corresponding to the load ball groove and front and rear end surfaces of the sliding table are mounted, and the load ball groove and each end of the escape ball raceway are communicated with each other on the inner surface side. A pair of lids having a guide groove that is connected to each other to form a ball endless track, and circulates in the ball endless track, and applies a load between the load ball groove of the slide table and the rolling groove of the track table. In a linear sliding bearing consisting of many balls, The diameter of the roller is selected to be larger than the distance between the load ball groove and the rolling groove that face each other, while a pair of mounting surfaces are formed on the upper surface of the horizontal part of the sliding base along the upper longitudinal direction of both sleeve parts. At the same time, a mounting base is mounted on the pair of mounting surfaces by a plurality of fastening bolts to form a gap located between the mounting surfaces between the upper surface of the horizontal portion and the lower surface of the mounting base,
A gap adjusting pressure bolt that penetrates the mount and contacts the horizontal portion at an intermediate position of the pair of mounting surfaces is screwed into the mounting base, and the gap adjusting pressure bolt is rotated to press the horizontal portion. A method for adjusting the clearance of a linear sliding bearing, which is characterized in that