JPH0353495B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is a linear sliding device for linearly guiding a movable body to be moved in a sliding part of a machine tool such as an NC machine or an industrial robot. Regarding bearings.

[Prior Art] Conventionally, this type of linear sliding bearing has a horizontal portion and sleeve portions that hang downward from both sides of the horizontal portion, and a concave portion that opens downward. has a pair of load ball grooves along the longitudinal direction of its inner surface, and a slide table with a gate-shaped cross section having a non-load ball passage corresponding to each load ball groove; a pair of lids attached to both end surfaces and having ball circulation paths on the inner surface for communicating and connecting the respective ends of the corresponding loaded ball grooves and non-load ball passages to form a ball endless track; It is formed by press-molding a metal plate and has a long hole whose width is slightly narrower than the diameter of the ball.It is installed between the pair of lids, and the long hole is located on the inner surface of each sleeve of the sliding table. a ball holder positioned along the load ball groove of the slider to prevent the balls rolling along the load ball groove from falling off; At the same time, rolling is carried out while applying a load between a rail-shaped wayway having a ball rolling groove corresponding to the load ball groove, and a load ball groove of the sliding base and a ball rolling groove of the wayway. A device consisting of a large number of running balls is known (Japanese Patent Publication No. 38812/1983).

[Problems to be Solved by the Invention] However, in the above-mentioned conventional linear sliding bearing, the ball retainer is formed by press-forming a thin metal plate, and the width dimension is larger than that of the ball. In addition to forming an elongated hole that is slightly narrower than the diameter, the ball retainer is attached between the pair of lids, so it is particularly susceptible to screws, and the ball retainer itself lacks strength and rigidity and may deform. It is easy to warp and the width of the long hole is distorted, making it difficult to process with precision. Even if it is machined with precision, it is easily distorted due to deformation, and contact with the ball may occur during use, causing noise. This may become an obstacle to smooth sliding movement, and the assembly of the ball holder and each lid to the slide table requires accurate positioning between these three parts, which requires manual labor. Unavoidably, there was a problem that it was difficult to automate the assembly.

Therefore, as shown in FIG. 18, for example, each sleeve portion of the sliding table 1 has ball rolling surfaces 10a and 10b at the bottom along the longitudinal direction of the inner surface, and the opening width l is larger than the diameter d of the ball 5. Forming small so-called dovetail-shaped load ball grooves 16a and 16b,
Furthermore, a pair of lids (not shown) having ball circulation paths are attached to both front and rear end surfaces of the slide table 1 to connect the corresponding ends of the load ball grooves 16a and 16b and the non-load ball hole 12. It is conceivable to connect them to each other to form a ball endless track. By forming the load ball grooves 16a and 16b in this manner, it is possible to prevent each ball 5 from falling off when the track base 4 is separated from the slide base 1 without using any ball holding means, and as described above. However, when such load ball grooves 16a and 16b are formed, the ball rolling surfaces 10a and 10b can be polished. First, the ball rolling surfaces 10a and 10b cannot be finished smoothly, making it impossible to achieve smooth sliding motion of the slide table 1, and also causing noise.

[Means for solving the problem] Therefore, the inventor of the present invention determined the positioning between each part by two methods.
It is possible to determine only the 1:1 relationship between the two parts, which allows each part to be machined with high precision and assembled with high precision, and the ball rolling surface of the load ball groove can be easily polished. The present invention was achieved through intensive research into linear sliding bearings that can be assembled automatically.

That is, the present invention includes a recessed portion that opens downward and has a horizontal portion and sleeve portions that hang downward from both sides of the horizontal portion, and each of the sleeve portions has a pair of sleeve portions extending along the longitudinal direction of the inner surface of the recessed portion. a sliding table having a substantially gate-shaped cross section and having load ball grooves and non-load ball passages corresponding to each of the loaded ball grooves; and a load ball groove formed on the inner surface of each sleeve of the sliding table. A ball holding means is arranged along the load ball groove to prevent the ball groove rolling along the load ball groove from falling off; and a pair of lid bodies having a ball circulation path for communicating and connecting each end of the unloaded ball passage to form a ball endless track;
a rail-shaped track whose upper part fits into the recess of the sliding table while maintaining a predetermined distance from each other and has a ball rolling groove corresponding to the load ball groove; and a load ball of the sliding table. In a linear sliding ball bearing consisting of a large number of balls that roll while applying a load between a groove and a ball rolling groove of the above-mentioned way, each sleeve of the above-mentioned sliding stand has a groove extending along its inner surface in the longitudinal direction. A groove that opens inward along the groove is formed, and upper and lower ball rolling surfaces are formed at the upper and lower corners of each groove, respectively, and a vertical wall between the upper and lower ball rolling surfaces is formed with a longitudinal direction. A dovetail groove is formed along the inner surface of each sleeve portion, and a retainer constituting a part of the ball retaining means protrudes continuously from the lower ball rolling surface formed at the lower corner of each concave groove. At the same time as attaching the plate, a holding member having a trapezoidal cross section and forming a part of the ball holding means is fitted into the dovetail groove formed in the groove, and the holding member is used to vertically move the groove. This is a linear sliding ball bearing that is partitioned to form a pair of load ball grooves.

In the present invention, the holding member fixed to each sleeve side and constituting a part of the ball holding means, in combination with the shape of each groove and the holding plate, comes into contact with the ball rolling on the above-mentioned upper and lower ball rolling surfaces. Any material may be used as long as it can prevent the balls from falling off by dividing the groove into upper and lower parts to form a pair of load ball grooves with an opening width smaller than the diameter of each ball, and the material, shape, etc. There is no limit to this, but it is preferably made of synthetic resin.

Further, each lid body may have a ball circulation path for forming a ball endless track by connecting each end of the corresponding loaded ball groove and unloaded ball passage. Preferably, a lid main body having four semicircular slots on its inner surface, and a semicircular portion that is fitted into the center of each slot of the lid main body and in which the ball circulates in conjunction with the peripheral edge of the slot. When installing, the R piece is fitted into the center of the slot in the lid body to form the lid body, and then this lid body is attached with bolts or other means. It is best to fix it to the end face of the sliding table.

[Operation] According to the technical means of the present invention, the mounting position of the holding member constituting the ball holding means is uniquely determined by the position where the dovetail groove is formed. This can be done with high accuracy in a 1:1 relationship with the sliding table without considering the mounting accuracy of the parts. Therefore, the load ball groove can be formed with high precision by these ball holding means that are mounted on the slide table with high precision, and contact between the ball holding means and the balls when the bearing is used is completely prevented.

Moreover, before the ball holding means is attached to the slide table, the ball rolling surface can be easily ground.

Furthermore, since the holding member and the ball holding plate are mounted in a 1:1 relationship with the sliding table, the mounting work is simplified and automation of bearing assembly can be achieved.

[Example] Hereinafter, the linear sliding bearing of the present invention will be specifically described based on the example shown in the accompanying drawings.

1 to 6, linear sliding bearings according to embodiments of the present invention are shown,
The sliding table 1 is basically formed in the shape of a gate in cross section.
, a ball holding means 2 attached to the sliding table 1 to prevent the balls 5 from falling off, a pair of lids 3 attached to both front and rear end surfaces of the sliding table 1, and a rail-shaped track 4. , the above-mentioned sliding table 1 and the above-mentioned track stand 4
It consists of a large number of balls 5 that roll while applying a load between them.

As shown in FIGS. 7 and 8, the sliding table 1 has a horizontal portion 6 and sleeve portions 7 that hang downward from both sides of the horizontal portion 6, and a concave portion 8 that opens downward.
A groove 9 opening inward is formed in each sleeve portion 7 along the longitudinal direction of the inner surface thereof,
Upper and lower ball rolling surfaces 10a and 10b are formed at the upper and lower corners of each groove 9, respectively, and a dovetail groove 11 is formed along the longitudinal direction between these ball rolling surfaces 10a and 10b. has been done. Further, each sleeve portion 7 of this sliding table 1 is formed with a no-load ball hole 12 that constitutes a no-load ball passage corresponding to each of the ball rolling surfaces 10a and 10b, and the lid body 3 is A stepped bolt hole 13a used for installation is drilled, and the horizontal part 6
Bolt holes 13b, which are used when attaching the lid 3, are bored at both front and rear ends of the cover.

The ball holding means 2 is composed of a holding plate 2a as shown in FIG. 9 and a holding member 2b as shown in FIG. 10. As shown in FIGS. 9 and 11, the holding plate 2a has a substantially L-shaped cross section and has a mounting portion 14a and a ball holding portion 14b, and each of the sliding bases 1 This ball holding part 14 is attached to the lower part of the inner surface of the sleeve part 7.
At the tip of b, a ball protrudes continuously from the lower ball rolling surface 10b located at the lower corner of the groove 9 formed on the inner surface of each sleeve 7 of the sliding table 1 to prevent the ball 5 from falling off. Holding tongue pieces 14c are formed on the front and rear ends of the mounting portion 14a, and as shown in FIG. Attached lid body 3
It is the same as or slightly protrudes from the surface of this lid body 3 to prevent the lid body 3 from colliding with a member such as a positioning stopper and being damaged during the sliding movement of the sliding base 1. A lid protection portion 14d is provided, and is attached to the lower inner surface side of each sleeve portion 7 of the sliding table 1 with screws 15. The holding member 2b is made of synthetic resin and has a trapezoidal cross section, as shown in FIGS. A pair of dovetail grooves 11 formed in the vertical wall of the ball 9 are fixed by fitting a part thereof into a dovetail groove 11 formed in the vertical wall of the ball 9, thereby dividing the groove 9 into an upper and lower part, and having an opening width at least smaller than the diameter of the ball 5. load ball groove 16
a, 16b are formed.

As shown in FIGS. 1, 6, and 12 to 16, each lid 3 has load ball grooves 16a, 16 formed on the sliding table 1 side.
Load ball communication side 1 connected to each end of b
7a and a no-load ball communication side 17b that is connected to each end of each no-load ball hole 12 corresponding to each load ball groove 16a, 16b for forming a ball endless track. The lid main body 3a has four semicircular slots 18 on its inner surface, and is formed in a substantially semicircular shape, around which the balls 5 circulate along the periphery of the slots 18. It has a circumferential groove 19 that forms a ball circulation path 17 for a half-circumference, and is composed of a radius piece 3b that is fitted into the center of each slot 18 of the lid body 3a. Furthermore, stepped insertion holes 20a and 20b are formed in each lid body 3 at positions corresponding to stepped bolt holes 13a and holes 13b drilled at both front and rear ends of the sliding table 1, respectively. When attaching each lid 3 to both the front and rear ends of the sliding table 1, position the lid 3 between the stepped bolt holes 13a and the stepped insertion holes 20a, as shown in FIG. The mounting bolts 22 are inserted through the stepped insertion holes 20a and 20b on the lid body 3 side, and the mounting bolts 22 are inserted into the stepped bolt holes 13a and bolt holes 13b on the slide table 1 side. It is designed to be screwed together.

Furthermore, as shown in FIG. 17 and FIGS. 1 to 5, the track base 4 has an upper portion that is connected to the slide base 1.
Ball rolling grooves 23a and 23b are formed in the recessed portions 8 of the ball bearings while maintaining a predetermined distance from each other, and corresponding to the ball rolling surfaces 10a and 10b in the load ball grooves 16a and 16b, respectively. ing.

Therefore, according to the linear sliding bearing of this embodiment, the grooves 9 are formed along the longitudinal direction of the inner surface of each sleeve portion 7, and the upper and lower balls roll in the upper and lower corners of each groove 9, respectively. The surfaces 10a and 10b are formed so as to protrude continuously from the lower ball rolling surface 10b formed at the lower corner of each groove 9 on the lower inner surface side of each sleeve portion 7, and constitute a part of the ball holding means 2. Attaching a retaining plate 2a to each ball rolling surface 10
Each sleeve portion 7 of the slide table 1 is fixed by attaching a holding member 2b constituting a part of the ball holding means 2 fixed to each sleeve portion 7 side along the longitudinal direction between a and 10b. A pair of load ball grooves 1 formed in
6a, 16b, and has four semicircular slots 18 on the inner surface of the lid body 3.
and a radius piece 3b fitted into the center of the slot 18 of the lid body 3a, and a radius piece 3b formed on the peripheral edge of the groove 18 formed on the lid body 3a side and on the radius piece 3b side. Since a ball circulation path 17 for forming a ball endless track with the circumferential groove 19 is formed, each component, namely the sliding table 1 and the holding plate 2a of the ball holding means 2 attached to this sliding table 1, The positioning of the holding member 2b and the lid body 3 can be determined only by a 1:1 relationship between the two parts, and the parts can be assembled with high accuracy.

[Effects of the Invention] As explained above, according to the linear sliding ball bearing of the present invention, the ball holding means consisting of the holding member and the ball holding plate can be mounted on the sliding table with high accuracy, and the ball holding means can Since the load ball groove can be formed with high precision, contact between the ball holding means and the ball is completely prevented when the bearing is used, achieving smooth sliding motion and minimizing noise generation. It becomes possible to prevent this.

In addition, since the ball rolling surface can be easily ground before assembling the bearing, it is possible to accurately form a load ball groove whose opening width is at least smaller than the ball diameter, while also improving the running accuracy of the slide table. can be secured.

Furthermore, automation of bearing assembly is achieved, which improves production efficiency and makes it possible to reduce bearing costs.

[Brief explanation of drawings]

FIG. 1 is a front view of a linear sliding bearing according to an embodiment of the present invention, FIG. 2 is a side view of FIG. 1, and FIG.
The figure is a plan view of Fig. 1, Fig. 4 is a cross-sectional view taken along the line - - of Fig. 2, Fig. 5 is a partial enlarged sectional view showing the main part of Fig. 4, and Fig. 6 is a cross-sectional view of Fig. 5. - line partial sectional view, Figure 7 is a front view of the sliding table, Figure 8 is a side view of Figure 7, Figure 9 is a perspective view of the retaining plate, Figure 10 is a perspective view of the retaining member, Figure 11 The figure is a cross-sectional view showing the above-mentioned holding plate and holding member attached to the sliding table.
Fig. 12 is a back view of the lid, Fig. 13 is a sectional view taken along the - line in Fig. 12, Fig. 14 is a sectional view taken along the - line in Fig. 13, Fig. 15 is a perspective view of the R piece, and Fig. 16 is a sectional view taken along the - line in Fig. 12. FIG. 17 is a partial cross-sectional view showing the state of attachment between the sliding base and the lid, FIG. 17 is a perspective view showing a part of the track base, and FIG. 18 is a possible cross-sectional view similar to FIG. 5. Explanation of symbols 1...Sliding base, 2...Ball holding means, 2a...Holding plate, 2b...Holding member, 3...Lid body,
3a...Lid body, 3b...R piece, 4...Railway, 5...Ball, 6...Horizontal part, 7...Sleeve part, 8...Concave part, 9...Concave groove, 10a, 10b...Ball rolling surface,
11... Dovetail groove, 12... No-load ball hole (no-load ball passage), 16a, 16b... Load ball groove, 17
...Ball circulation path, 18...Slot hole, 19...Circumferential groove, 2
3a, 23b...Ball rolling groove.

Claims (1)

[Scope of Claims] 1. A concave portion that opens downward and has a horizontal portion and sleeve portions that hang downward from both sides of the horizontal portion, and each of the sleeve portions has a concave portion that has a concave portion that opens downward. A sliding base having a substantially gate-shaped cross section and having a pair of loaded ball grooves and a non-loaded ball passage corresponding to each of the loaded ball grooves, and a loaded ball formed on the inner surface of each sleeve of the sliding base. Ball holding means arranged along the groove to prevent balls rolling along the load ball groove from falling off; and load ball grooves attached to both front and rear end surfaces of the slide table and corresponding to each other on the inner surface. and a pair of lid bodies each having an endless ball circulation path for communicating and connecting each end of the unloaded ball passage to form an endless ball track; A rail-shaped wayway that maintains and fits together and has a ball rolling groove corresponding to the load ball groove, and a load ball groove of the sliding base and a ball rolling groove of the wayway. In a linear sliding ball bearing consisting of a large number of balls that roll while being loaded, each sleeve of the sliding table has a groove that opens inward along the longitudinal direction of the inner surface of the sleeve. Upper and lower ball rolling surfaces are formed at the upper and lower corners of the concave groove, respectively, and dovetail grooves are formed along the longitudinal direction on the vertical wall between these upper and lower ball rolling surfaces, and the inner surface of each sleeve section is formed with a dovetail groove. A retaining plate constituting a part of the ball retaining means is attached to the lower part of the groove so as to protrude continuously from the lower ball rolling surface formed at the lower corner of each groove. A straight line characterized in that a holding member having a trapezoidal cross section and forming a part of the ball holding means is fitted, and the holding member partitions the concave groove into an upper and lower part to form a pair of loaded ball grooves. Sliding ball bearing.