JPH0353496B2 - - 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] This type of linear sliding bearing has a horizontal portion and sleeve portions that hang down from both sides of the horizontal portion, and a concave portion that opens downward. A sliding table having a substantially gate-shaped cross section and having a pair of load ball grooves along the longitudinal direction of the inner surface and a non-load ball passage corresponding to each of the load ball grooves, and both front and rear end surfaces of the sliding table. A pair of lids each having a ball circulation path on the inner surface for communicating and connecting each end of the corresponding loaded ball groove and non-load ball passage to form a ball endless track, and a width dimension. has an elongated hole that is slightly narrower than the diameter of the ball, and this elongated hole is located along the load ball groove on the inner surface of each sleeve of the slide table, and prevents the balls rolling along the load ball groove from falling off. a ball holder; a rail-shaped track whose upper portion fits into the recess of the sliding table while maintaining a predetermined distance from each other; and a rail-shaped track having a ball rolling groove corresponding to the load ball groove; There is known a ball bearing that consists of a large number of balls that roll while being loaded between a load ball groove of a sliding table and a ball rolling groove of the track base (Japanese Patent Publication No. 57-38812).

In a linear sliding ball bearing having such a ball holder, the balls will not fall off from the sliding base even when the sliding base is separated from the track base.
It has the advantage of improving workability when incorporated into machine tools, etc.

Conventionally, this type of ball retainer has been made of various types, such as those molded by injection molding of synthetic resin to fit the inner surface of the recess of the slide table, or those made by press molding of a thin metal plate. There is. Examples of this fixing method include a method of directly fixing to the slide table by screwing several places, and a method of indirectly attaching to the slide table using a pair of lids attached to the ends of the slide table.

[Problems to be solved by the invention] By the way, in linear sliding bearings,
Since the ball rolls at high speed while applying a load, vibrations occur in the sliding table, although very slightly. However, since the ball retainer that is attached to the slide table using the above-mentioned fixing method is only partially supported by means such as screws, it is difficult to ensure that the entire ball retainer is firmly integrated with the slide table. I can't say that. As a result, vibrations applied to the slide table may deform the ball holder or cause errors such as loosening or misalignment of the ball holder when attached to the slide table, especially between the two rows of rolling balls provided on the sleeve. This phenomenon is noticeable because a large impact is applied to the ball holder due to the above-mentioned vibration. Such deformation of the ball holder or misalignment of the mounting position may lead to contact between the rolling balls and the ball holder, causing noise generation or impeding smooth sliding movement. have.

In addition, the ball holder is required to be thin in order to avoid contact with the track base. Shikashi,
Ball holders that have been commonly used in the past, that is, ball holders that have long holes for holding balls, are relatively large in size and are easily deformed and come into contact with rolling balls. It has the following drawbacks.

Furthermore, the ball holder must be mounted on the slide table with high precision to avoid contact with rolling balls when the bearing is in use, which is one factor that hinders the automation of bearing assembly.

From the above point of view, a structure in which the sliding table can have a ball holding function without using a ball holder, for example, a so-called dovetail structure in which the opening width is smaller than the ball diameter and the internal width is larger than the ball diameter, is proposed. Ideally, a groove-like deep groove is formed in the slide table by cutting, and the ball is caused to roll using this deep groove as a load ball groove.

However, when such load ball grooves are formed on the slide table as an actual product, it is not possible to grind the ball rolling surface on the inner bottom, making it difficult to achieve smooth sliding movement of the slide table. Not only is this not possible, but it also causes noise.

[Means for Solving the Problems] Therefore, the inventors of the present invention have devised a structure in which the ball holding is approximated to the ideal form, the ball rolling surface is easy to grind, and it is possible to assemble with high precision. The present invention was developed as a result of extensive research into linear sliding ball bearings that can be automated.

That is, the present invention is provided with a recess 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 thereof. A slide table having a substantially gate-shaped cross section and having load ball grooves and non-load ball passages corresponding to each load ball groove; a pair of lid bodies each having an endless ball circulation path for forming an endless ball track by connecting each end of the corresponding loaded ball groove and unloaded ball passage; mutually prescribed 〓
a rail-shaped wayway that is fitted with a distance between them and has a ball rolling groove corresponding to the load ball groove, and a load ball groove of the slider and a ball rolling groove of the wayway; In a linear sliding ball bearing consisting of a large number of balls that roll while applying a load, a pair of upper and lower loaded ball grooves on one side are formed along the longitudinal direction of the inner surface of each sleeve of the sliding table. Formed along the longitudinal direction of the inner surface of the sleeve,
A wide concave groove having a ball raceway surface at each of the upper and lower corners and a dovetail groove formed between these upper and lower raceway surfaces, and a wide concave groove that continues from the ball raceway surface formed at the lower corner of the concave groove. A ball holding plate having a protruding holding piece, a partition member fitted into the dovetail groove to partition the groove into an upper and lower part, and ball holding pieces along both longitudinal directions, and a horizontal lower surface inside the recess of the sliding table. It is characterized in that it is formed with a ball holding substrate attached to the side, and is formed into a deep groove whose opening width is at least smaller than the diameter of the ball.

In the present invention, each lid body may have a ball circulation path for connecting each end of the corresponding loaded ball groove and unloaded ball passage to form a ball endless track. but,
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.

[Function] According to the present invention, since the partition wall member constituting the load ball groove is fitted to the slide table by the dovetail groove formed in the groove of the slide table, this partition wall member is firmly attached. It can be said that it is integrated with the slide table, and the ball holding form on the slide table approximates the ideal ball holding form.

In addition, since the partition wall member, ball holding plate, and ball holding board that make up the load ball groove are manufactured as separate members from the slide table, the inner bottom of the load ball groove must be sealed before being fixed to the slide table. The ball rolling surface can be easily ground.

Furthermore, since the installation accuracy of the partition wall member is uniquely determined by the formation position of the dovetail groove, there is no correlation between the installation of the partition wall member and the ball holding plate or ball holding board, and the ball holding plate and The ball holding board can be easily attached.

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

1 to 6, a linear sliding ball bearing according to a first embodiment of the present invention is shown. This linear sliding ball bearing has a sliding base 1 having a substantially gate-shaped cross section, which has a horizontal portion 5, sleeve portions 6 that hang downward from both sides thereof, and a recessed portion C that opens downward. a pair of lids 2 attached to both front and rear end surfaces of the sliding table 1; and a rail-shaped track whose upper part fits into the recess C of the sliding table 1 while maintaining a predetermined distance from each other. 3, a large number of balls 4 that roll while applying a load between the sliding table 1 and the track 3, and the sleeve portion 6 of the sliding table 1.
Ball holding plate 18 attached to the lower part of the inner surface of
, a partition wall member 19 fitted to the inner surface side of the sleeve portion 6 of the sliding table 1, and a holding piece 22 attached to the lower surface side of the horizontal portion 5 in the recess of the sliding table 1 and along both sides.
The ball holding board 21 has a ball holding board 21.

As shown in FIGS. 4 to 7, the sliding table 1 includes, along the inner longitudinal direction of each sleeve portion 6,
A pair of upper and lower load ball grooves 8a and 8b are formed on one side, each of which has ball rolling surfaces 7a and 7b inside and is composed of a pair of upper and lower deep grooves whose opening width l is at least smaller than the diameter d of the ball 4. There is. These load ball grooves 8a, 8b are formed along the longitudinal direction of the inner surface of each sleeve portion 6, and are wide concave grooves 16 having the ball rolling surfaces 7a, 7b at the upper and lower corners.
and a ball rolling surface 7b attached to the lower part of the inner surface of each sleeve portion 6 and formed at the lower corner of the groove 16.
A ball holding plate 18 having a substantially L-shaped cross section and having a holding piece 17 continuously protruding from the ball holding plate 18 (see FIG. 15).
and a partition member 19 having a substantially trapezoidal cross section that fits into the dovetail groove 20 formed between the upper and lower rolling surfaces 7a and 7b in the groove 16 to partition the groove 16 into upper and lower sections (see FIG. 16). A ball holding substrate 21 ( (see FIG. 17). Further, along the longitudinal direction of each sleeve portion 6, a non-load ball hole 9 forming a non-load ball passage corresponds to the load ball grooves 8a, 8b.
is drilled.

Furthermore, the lids 2 attached to both the front and rear ends of the sliding table 1 are shown in FIGS. 1, 6, and 9 to 1.
As shown in FIG. 2, each end of each load ball groove 8a, 8b formed on the sliding table 1 side and each end of each non-load ball hole 9 corresponding to each of these load ball grooves 8a, 8b. It has a ball circulation path 10 for forming a ball endless track by connecting the lid body 2a with four semicircular slots 11 on the inner surface, and a lid body 2a formed in a substantially semicircular shape. The ball 4 is attached to the periphery of the ball 4 along with the periphery of the slot 11.
It has a circumferential groove 12 forming a semi-circular ball circulation path 10 in which the ball circulates, and each slot 1 of the lid main body 2a
1 and a round piece 2b fitted into the center of the inside. Each of the lids 2 is installed using stepped bolt holes at both the front and rear ends of the sliding table 1.
2a and bolt holes 12b, and each lid body 2 is provided with the stepped bolt holes 12a and bolt holes 12b.
A stepped insertion hole 13a and an insertion hole 13b corresponding to the holes 13a and 13b are opened, respectively, and a bush 14 for positioning the lid body 2 is provided between each stepped portion of the stepped bolt hole 12a and the stepped insertion hole 13a, as shown in FIG. is inserted, and the lid body 2
Insert the mounting bolt 14 through the stepped insertion hole 13a and insertion hole 13b on the side, and insert the mounting bolt 14 into the stepped bolt hole 12a and bolt hole 12b on the sliding table 1 side.
It is done by screwing together.

Further, as shown in FIG. 14 and FIGS. 1 to 5, the upper part of the track base 3 is fitted into the recess C of the slide base 1 while maintaining a predetermined distance from each other. Corresponding ball rolling grooves 15a and 15b are formed in each of the ball rolling surfaces 7a and 7b in the loaded ball grooves 8a and 8b, respectively.

In the linear sliding ball bearing of this embodiment configured in this way, the ball rolling surface is fixed by attaching the ball holding plate 18 and the ball holding board 21 to the sliding table 1 and forming the load ball grooves 8a and 8b. The grindstone for grinding 7a and 7b can be easily brought into contact with the upper and lower corners of the groove 16, and the grinding process can be easily performed accordingly.
The ball holding plate 18 and the ball holding board 21 can also be fixed to the slide table 1 by projection welding, thereby making it easier to automate the assembly of the bearing.

[Effects of the Invention] According to the linear sliding ball bearing of the present invention, the ball holding on the sliding table approximates the ideal ball holding form, and the rolling balls come into contact with the ball holding means such as the load ball groove. This eliminates the need for smooth sliding motion of the sliding table, and also prevents noise generation as much as possible. Furthermore, since the ball rolling surface located at the inner bottom of the load ball groove can be easily ground before assembling the bearing, it is possible to commercialize the product with sufficient sliding accuracy.

Furthermore, since the ball holding plate and the ball holding board can be easily attached, precise manual assembly is not required, and bearing assembly can be automated.

[Brief explanation of drawings]

FIG. 1 is a front view of a linear sliding ball bearing according to a first embodiment of the present invention, FIG. 2 is a side view of FIG. 1, FIG. 3 is a plan view of FIG. 1, and FIG. 4 is a second Figure 5 is a partially enlarged sectional view showing the main part of Figure 4, and Figure 6 is a - line sectional view of Figure 5.
Line partial sectional view, Figure 7 is a front view of the sliding table, Figure 8
The figure is a side view of Fig. 7, Fig. 9 is a back view of the lid, Fig. 10 is a sectional view taken along the line - - of Fig. 9, Fig. 11 is a sectional view taken along the line XI-XI of Fig. 10, and Fig. 12. Figure 13 is a partial sectional view showing the state of attachment between the sliding base and the lid, Figure 14 is a perspective view of a part of the track, and Figure 15 shows the ball holding plate. FIG. 16 is a perspective view showing a partition member, and FIG. 17 is a perspective view showing a ball holding board. [Explanation of symbols], 1...Sliding base, 2...Lid body,
3...Railway platform, 4...Ball, 5...Horizontal part, 6
... Sleeve part, C ... Recessed part, 7a, 7b ... Ball rolling surface, 8a, 8b ... Load ball groove, 9 ... No-load ball hole (no-load ball passage), 10 ... Ball circulation path, 15a, 15b...Ball rolling groove, 1
6... Concave grooves 16, 17... Holding piece, 18... Ball holding plate, 19... Partition wall, 21... Ball holding board.

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 pair of sleeve portions along the longitudinal direction of the inner surface thereof. A slide table having a substantially gate-shaped cross section and having load ball grooves and non-load ball passages corresponding to each load ball groove; a pair of lid bodies each having an endless ball circulation path for forming an endless ball track by connecting each end of the corresponding loaded ball groove and unloaded ball passage; a rail-shaped wayway that fits together while maintaining a predetermined distance from each other and has a ball rolling groove corresponding to the load ball groove; 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 between a groove and a load while applying a load, a pair of load balls on one side, upper and lower, formed along the longitudinal direction of the inner surface of each sleeve of the sliding base. The groove is a wide groove formed along the longitudinal direction of the inner surface of each sleeve, and has a ball rolling surface at the upper and lower corners, and a dovetail groove formed between the upper and lower rolling surfaces, and this groove. a ball holding plate having a holding piece that protrudes continuously from the ball rolling surface formed at the lower corner of the plate;
It has a partition member fitted into the dovetail groove and partitioning the concave groove into upper and lower parts, and ball holding pieces along the longitudinal direction on both sides,
A ball bearing for linear sliding, characterized in that it is formed by a ball holding substrate attached to the horizontal lower surface side of a recessed part of a sliding table, and is formed into a deep groove whose opening width is at least smaller than the diameter of the ball.