JPH03117719A - Gap adjusting method for linear slide bearing - Google Patents

Abstract

PURPOSE:To adjust a gap between balls easily by providing a gap on the horizontal upper face of a slide base which is slided on a track support to mount a mounting base and inserting gap adjusting differential bolts, the upper and the lower portions of which are different in pitch, therein to elastically transform the slide base. CONSTITUTION:With a linear slide bearing B, a slide base 1 is slided on a track support 2 with interposition of balls 4 between them. The mounting face 11 of a mounting base 12 is threaded onto the horizontal portion 5 of the slide base 1 with fastening bolts 13 to form a gap D. On the center line of the horizontal portion 5, gap adjusting differential bolts 16 are provided, the upper and the lower portions of which are different in pitch. The differential bolts give the horizontal portion 5 upward or downward force, depending on a rotational movement direction, to elastically transform the slide base 1. Such adjustment causes a gap (d) between a sleeve portion 6 and the track support 2 to be adjusted. It is thus possible to perform the gap adjustment of the balls easily after the bearing is assembled in a machine device.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a linear sliding bearing that linearly guides a movable body to be slid in a sliding part of a machine tool such as an NC machine or an industrial robot. In particular, the present invention relates to a gap adjustment method in a linear sliding bearing for applying pressurization to balls rolling between a sliding base and a track base that constitute the bearing.

[Prior Art] A linear sliding bearing usually has a sliding base having a substantially inverted C-shaped cross section with a recess on the lower surface side, and the upper part is fitted into the recess of the sliding base while maintaining a predetermined gap. It has a track base, and a large number of balls that circulate in a ball endless track formed on the slide base, and these balls apply loads acting on the slide base in the vertical and horizontal directions. and is configured to guide linear reciprocating motion along the line.

Such linear sliding bearings are required to be able to be incorporated with high precision into the sliding parts of general industrial machinery, have good positioning and repeatability, and have a long life. In order to provide such characteristics, it is necessary to reduce the distance between the load ball groove of the sliding base and the rolling groove of the way, where the balls that apply the load roll between the sliding base and the way. It is important to set the ball in a negative state compared to the diameter of the ball mentioned above, thereby applying pressurization to the balls to increase the hitting rate of all balls, and to prevent hammer action and prying loads caused by the moment of inertia when changing direction. It is also important that each ball circulating in the ball endless track smoothly circulates from its no-load area to its loaded area or from its loaded area to its no-load area.

For this reason, in the past, as a means of applying pressurization to the balls, ball selection fitting, in which balls are selected and fitted with their diameters aligned, has been used, or grooves have been formed in the sleeves of the slide table. Methods such as adjusting the gap between the slide table and the track base using bolts are also used, and as a means of smoothing the circulation of the balls within the ball endless track, the load ball of the slide base is A so-called crowning process, in which the grooves are widened at both ends and narrowed at the middle, is performed.

[Problem to be solved by the invention]

However, ball selective fitting, which is performed as a means of applying pressurization to the balls, is extremely time-consuming work, and ball selective fitting and gap adjustment performed from the side of the slide table do not allow the bearing to slide into the machine. There is a problem in that it is difficult to adjust the pressurization applied to the balls depending on the purpose of use of the bearing, and it is also difficult to crown the load ball groove of the sliding table. The work performed also had a problem in that it had to be finished with good processing accuracy, which was extremely time-consuming work.

The present invention was made in view of these problems,
The purpose is to provide a gap adjustment method for linear sliding bearings that allows pressurization to be freely applied to the balls and to adjust the degree of pressurization even after the bearing is assembled into a mechanical device. be.

[Means to solve the problem]

In order to achieve the above object, the method for adjusting the clearance of a linear sliding bearing of the present invention includes forming a pair of mounting surfaces on the upper surface of the horizontal part of the sliding table along the upper longitudinal direction of both sleeves, and A mounting base is attached to the pair of mounting surfaces using a plurality of fastening bolts, and a gap is formed between the upper surface of the horizontal portion and the lower surface of the mounting base, and a gap is formed between the mounting base and each of the mounting surfaces. A through hole or gap adjustment screw hole is provided in the horizontal part of the sliding table between the two holes, and the gap adjustment differential bolt screwed into both holes is rotated to allow the slider to slide. It is characterized by giving elastic deformation to the horizontal part of the table.

[For production]

According to such technical means, the clearance adjustment differential bolt is screwed into both the through hole of the mounting base and the clearance adjustment screw hole of the sliding base, each having a female threaded portion having a pitch difference from each other. By selecting the direction of rotation of the clearance adjustment bolt, a force in the lifting direction or a force in the pressing direction acts on the horizontal portion of the sliding table. Therefore, the gap between the inner surface of each sleeve of the sliding base and the outer surface of the way can be freely narrowed or widened, and the gap between the load ball groove of the sliding base and the rolling groove of the way can be freely narrowed or widened. Any preload can be applied to the sandwiched balls.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for adjusting a gap in a linear sliding bearing according to the present invention will be explained in detail based on the accompanying drawings.

1 to 5 show a linear sliding bearing B to which an embodiment of the method of the invention is applied. This bearing B has a horizontal portion (5) and a pair of sleeve portions (6) hanging downward from both sides of the horizontal portion (5), and has a trapezoidal recess (7) on the lower surface side. The portion (6) has a substantially semicircular load ball groove (8) along the longitudinal direction of the inner surface thereof, and an escape ball hole (9) forming an escape ball trajectory corresponding to each of these load ball grooves (8). A sliding base (1) having a substantially inverted C-shaped cross section is bored, and a trapezoidal upper part is fitted into the recess (7) of the sliding base (1) while maintaining a predetermined gap from each other. A track base (2) having a substantially semicircular rolling groove 00) that matches the load ball groove (8) and corresponds to the load ball groove (8); a pair of lids (3) having guide grooves (not shown) that communicate and connect each end of the load ball groove (8) and the escape ball hole (9) to form a ball endless track; , the ball circulates within the endless track, and the sliding table (1
) of the load ball groove (8) and the rolling groove of the wayway (2) (Go)
It consists of a large number of balls (4) that apply a load between them.

As shown in FIG. 1 and FIGS. 3 to 5, on the upper surface of the horizontal part (5) of the sliding table (1), there is a pair of mounting surfaces ( 11) are formed, and a mounting base (I
A mounting hole (I4) is drilled into which the fastening bolt (13) is screwed when installing the ZI, and the horizontal part (5)
A concave surface (15) is formed on the upper surface so that a predetermined gap is formed between each of the mounting surfaces (11) and the lower surface of the mounting base (12).

The mounting base (12) also has a mounting surface (11) that is located between a pair of mounting surfaces (11) that pass through the mounting base (12) and are formed on the upper surface of the horizontal portion (5) of the sliding base (1). Horizontal center line! A gap adjustment differential bolt (lω (hereinafter referred to as differential bolt) that acts on this horizontal portion (5) is provided at the top.

This differential bolt (16) has a male threaded portion with a pitch difference between the upper and lower parts, and on the mounting base ( While the nut (23) is fitted and screwed into the female thread formed in the through hole (24) of the nut, on the sliding table side, the gap adjustment screw drilled above the horizontal center line! It is screwed into the female threaded part of the hole (171).

Note that the original number (la) in Figures 1 to 4 above is a bed having a mounting reference surface (19) when fixing the track base (2) of the bearing B to various mechanical devices; In FIG. 5, the symbol ■ is a mounting bolt that fixes the lid (3) to both the front and rear end surfaces of the sliding base (1).

Next, regarding the bearing B according to this example, we will explain how to assemble it to various mechanical devices and its sliding base (1) and track base (2).
A method of adjusting the gap d between the two will be explained.

First, the track base (2) was fixed to the mounting reference surface (19) of the bed of various mechanical devices (IEI), and the bearing B was installed. Place the mounting base (D) on the mounting surface (1υ, raise its height and tighten it) (13) and attach the mounting base (12).
) to be fixed.

After installing the bearing B in this way, rotate the differential bolt (1) from the top of the mounting base (see the figure) while observing the sliding condition of the bearing B.

At this time, since the female threaded portion of the through hole (24) and the female threaded portion of the gap adjustment screw hole (IT) have a pitch difference from each other, in one direction of rotation, the differential pole l-(
1G) applies a force in the direction of arrow Y1 to the upper surface of the horizontal part (5) of the slide table (1), causing elastic deformation as shown by the two-dot chain line in Fig. 6, thereby deforming the slide table (1). The distance between the sleeves (6) is widened, thereby increasing the distance between the sleeves (6) of the slide table (1).
) The initial gap d between the inner surface and the outer surface of the track (2) is d
Expand to l. In addition, in other rotation directions, the differential bolt (1ω) applies a force in the direction of arrow Y2 to the upper surface of the horizontal part (5) of the sliding table (1), and the elastic force as shown by the two-dot chain line in FIG. By causing deformation, both sleeves of the sliding table (1) (
6) narrowing the spacing between them, thereby reducing the initial gap d between the inner surface of each sleeve (6) of the sliding platform (1) and the outer surface of the track platform (2) to d.

Therefore, by selecting the direction of rotation of the differential bolt (16), it is possible to apply a force in the pressing direction to the horizontal part (5) of the sliding table (1), or apply a force in the lifting direction. The sliding table ( 1) arbitrarily adjust the interval dimension between the load ball groove (8) formed on the inner surface of each sleeve portion (6) and each rolling groove (10) formed on the outer surface of the track base (2),
A predetermined pressurization can be applied to each ball (4) rolling in the load ball groove (8).

Note that a plurality of these differential bolts (1ω) may be provided at appropriate positions depending on the length of the sliding table (1).

Furthermore, linear sliding bearing B to which the method of the present invention is applied
is not limited to those of the above embodiments, for example, a sliding table having a bearing race in which one of the load ball grooves (one is formed) is used.
1) or a sliding table with two ball tracks on each sleeve, the sliding table (1 ) by adjusting the gap d between the inner surface of each sleeve portion (6) and the outer surface of the track base (2), it is possible to apply a predetermined pressurization to each ball (4) in the load area.

[Effects of the Invention] As explained above, according to the method for adjusting the clearance of a linear sliding bearing of the present invention, each sleeve of the sliding base can be adjusted by rotating the clearance adjustment differential bolt in an arbitrary direction. The gap between the inner surface of the bearing and the outer surface of the track can be freely narrowed or widened. A predetermined preload can be applied to the balls sandwiched between the load ball groove of the moving base and the rolling groove of the way base,
There is no need to selectively fit the balls, which is very time-consuming, or to adjust the gap from the side of the slide table, which is difficult in terms of downsizing the mechanical device.

[Brief explanation of drawings]

FIG. 1 is a front view showing an assembled state of a linear sliding bearing to which a gap adjustment method according to an embodiment of the present invention is applied, FIG. 2 is a side view of FIG. 1, and FIG. 3 is a side view of FIG. 1. Plan view of 4th
The figure is a sectional view taken along the line IV-IV in Figure 3, Figure 5 is a plan view of the bearing with the mounting base removed in Figure 3, and Figures 6 and 7 are elasticity of the horizontal part of the sliding base. FIG. 3 is an explanatory front view showing an exaggerated state of deformation. [Explanation of symbols] B: Bearing (1): Sliding base (2): Track base (3): Lid body (4) Two balls (5): Horizontal part (6): Sleeve part (
7): Recess (8): Load ball groove (9): Relief ball hole 00): Rolling groove (111: Mounting surface ((2)
): Mounting base (13): Fastening bolt +16)
: Gap adjustment differential bolt (1η: Gap adjustment screw hole l: Horizontal center line d: Gap D2 gap

Claims (1)

[Scope of Claims] It has a horizontal portion and a pair of sleeve portions that hang downward from both sides of the horizontal portion, and has a recessed portion on the lower surface side, and the both sleeve portions are loaded along the longitudinal direction of the inner surface thereof. A sliding table having a substantially inverted C-shaped cross section and having ball grooves and relief ball trajectories corresponding to each of these load ball grooves, and an upper portion thereof are fitted into a recessed portion of the sliding table while maintaining a predetermined gap from each other. At the same time, a track base having rolling grooves corresponding to the load ball grooves is attached to both the front and rear end surfaces of the slide base, and on the inner surface, a track base is installed between each end of the load ball groove and the relief ball raceway. A pair of lids having guide grooves that are connected to each other to form a ball endless track, circulate within the ball endless track, and load a load between the load ball groove of the sliding base and the rolling groove of the way base. In a linear sliding bearing consisting of a large number of balls, a pair of mounting surfaces are formed on the upper surface of the horizontal part of the sliding table along the upper longitudinal direction of both sleeves, and a pair of mounting surfaces are formed on the pair of mounting surfaces. A mounting base is attached using a plurality of fastening bolts, and a gap is formed between the upper surface of the horizontal part and the lower surface of the mounting base, and the sliding base is horizontal between the mounting base and each of the mounting surfaces. A through hole or a gap adjustment screw hole is provided in the section with female threads having a pitch difference from each other, and by rotating the gap adjustment differential bolt that is threaded into both holes, the horizontal section of the slide table is elastically deformed. A method for adjusting the gap of a linear sliding bearing, which is characterized by giving the following.