JPH02113114A - Journalled roller type bearing for linear motion - Google Patents

Abstract

PURPOSE:To obtain a bearing for linear motion eliminating the need for a rolling element circulation mechanism by assembling a bearing assembly body having rollers journalled at one side of a table so as to abut against the rods of a raceway device consisting of the rods fitted ad fixed into recessed parts lengthwise extending along the surfaces of a base. CONSTITUTION:Recessed parts 25, 25 are formed on the side surfaces of a base 20, and rods 21, 21 are pressure-fitted or fitted and fixed into the recessed parts. A bearing assembly body 13 holds a table 30 and four rollers 40, on the outer peripheral surfaces of which recessed parts 45 are formed at the lower side of the table 30, and it is installed at a position where the rollers can hold the rods 21, 21 of the raceway device 12. With this structure, the need for a complex circulation mechanism is eliminated, no vibration, etc., is created, and thereby a bearing for linear motion capable of being smootly travelled can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a linear motion bearing used for guiding linear motion parts such as tables and positioning tables of machine tools.

BACKGROUND OF THE INVENTION Conventionally, linear motion bearings enable guidance through rolling contact between a track and a bearing body by endlessly circulating a large number of rolling elements such as balls or rollers.

Therefore, this kind of device requires a complicated mechanism for circulating the transmission body, which makes it difficult to manufacture at A-prices and has the problem of high cost.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and provide a linear motion bearing that does not require a rolling element circulation mechanism.

Means for Solving the Problems The present invention provides a track base having a base having a recess extending in the longitudinal direction on its side surface, and a rod fitted and fixed in the 6N recess. This base can be made of aluminum or resin to make it lightweight. Note that the rod is preferably a hardened #4-ground rond.

The present invention also provides a bearing assembly comprising a pedestal and a roller pivotally supported on one surface of the pedestal so that a recess formed on the outer circumferential surface abuts a rod of the track. In this bearing assembly, the roller can be preloaded by adjusting its pivot position using an eccentric bolt.

A linear motion bearing is constructed from the Moe's track base and bearing assembly.

Function: The track base of the present invention does not have an integrally formed load groove as in the prior art, and provides a load surface on which the bearing assembly runs on the outer circumferential surface of the rod.

The shaft support roller of the bearing assembly contacts the outer peripheral surface of the rod at its outer peripheral surface, and rolls due to frictional force to guide the pedestal in the longitudinal direction.

The roller is in contact with the rod, and by adjusting the shaft support position of the roller with an eccentric bolt, a preload can be applied between the outer circumferential surface of the rod and the recess on the outer circumferential surface of the roller.

Embodiment FIGS. 1 to 3 show a perspective view, a plan view, and a front view of a linear motion bearing 10 according to a first embodiment of the present invention. The linear motion bearing 10 includes a track 12 and a bearing assembly 13.

As shown in FIGS. 4 and 5, the track 12 consists of a base 20 and rods 21, 21.

The base 2o is composed of a bottom portion 22 and a head portion 24. The bottom part 22 has a flat surface 2 on the lower surface for installation on a mounting surface.
3.23 is formed, and the head 24 expands to the left and right,
Recesses 25 that open laterally in both of its expanding parts.
25 is formed. There is a constriction between the bottom part 22 and the head part 24, and the new surface forms a substantially truncated conical groove 26,26.

The new surface of the recess 25.25 in this embodiment is rectangular.

Reference numeral 28 indicates a bolt hole for installation.

The rods 21.21 are press-fitted or fixed in the recesses 25, 25 so that they cannot easily fall out, or the recesses 25, 25 are of such size. Also, recess 2
5 has a depth that allows the outer peripheral surface of the rod 21 to partially protrude from the opening of the recess 25 when the rod 21 is inserted.

Conventionally, the base 20 is made of iron, but in the present invention, it can be made of aluminum, aluminum alloy, or wood. The bearing assembly 1 is attached to the rod 21.
Since the shaft support roller 40 (described later) in No. 3 comes into pressure contact with the bearing assembly, a hardened bearing steel with high hardness and wear resistance is desirable, and it is desirable to grind the bearing assembly in order to ensure running accuracy of the bearing assembly 13. Further, in cases where #abrasion resistance is particularly required, only the rod 21 may be specially manufactured. Therefore, the base 20 is not required to have much strength, and even a material such as aluminum described above can function satisfactorily.

In some cases, the bearing assembly 13 is fixed and the track 12 side is moved, so in such applications, it is possible to reduce the inertial weight and obtain smooth running performance by using light materials as described above. can. Also, rod 2
Since 1 has a cylindrical shape, it is easy to process such as grinding, and it is easy to achieve accuracy such as roundness and straightness.

FIGS. 6 and 7 show modified examples of the track base. The former track 12a is the same as the track 12 shown in FIG. 5, except that a longitudinally extending fitting recess 29 is formed in place of the bolt hole 28 for installation. This track 12a is preferably solid in the direction of the load from the bearing assembly 13, that is, in the direction of the contact angle of the rollers 40. The track 12b shown in FIG. 7 has an even more compact structure, having no bottom and only a head for receiving the rods 21 and 21. Note that bolt holes (not shown) are provided.

Returning to FIGS. 1 and 3, the bearing assembly 13 includes a pedestal 30, four rollers 40 each having a recess 45 formed in an outer peripheral surface 44 on the lower surface of the pedestal 30, and a rod of the track 12. 2 for pivoting in a position where 21, 21 can be gripped! 1 bolt 51.52.

The frame 30 is rectangular as shown in FIG. 2, and has screw holes 3 for attaching bolts 51 and 52 for the roller 40.
1 and 32, a screw hole 33 for attaching a table, etc., and a screw hole 34 for attaching a sealing device 60 and 70 to be described later.

8 and 9 show the roller 40, and the roller of this embodiment is the outer ring 4 of a shield type double row outward angular contact ball bearing.
3 with a recess 45, which will be described later, and has a structure having a contact angle that resists moment load. In addition,
Some bearings are of the rubber seal type. The inner peripheral surface 42 of the inner ring 41 when viewed as a bearing is
．． 52. The outer circumferential surface 44 of the outer ring 43 is provided with a recess 45 having a shape that matches the outer circumferential surface of the rod 21 of the track base 12.
is formed. As shown in FIG. 9, the recess 45 has a Gothic arch shape, is inclined in the same direction as the contact angle of the bearing, and cooperates with the recess 45 to support the moment load generated on the pedestal 30. Furthermore, as shown in FIG. 10, there is also an outer ring 43a in which a recess 45a having a truncated conical cross section is formed.
Like the Gothic arch shape, it can handle moment loads. The included angle of the recess 45a of this outer ring 43a is 100°.

11 to 14 show poles 1 to 5.1, 52. for pivotally supporting the roller 40 on the frame 30. A nut 36 and a washer 37 are shown, and a bolt 51 for attaching a roller located on one rod of the track 12 and a bolt 52 for attaching a roller located on the other rod have different shapes. Note that both rollers 4o are the same.

The first pol 1-51 is as shown in Figures 11 and 12,
It is a standard bolt, consisting of a threaded part 55 for attachment to the frame 30, a shank 53 and a head 58 that are lightly press-fitted into the inner peripheral surface 42 of the inner ring 41 of the roller 4o, and is symmetrical with respect to the center line. It is.

The second bolt 52 is a double-thread type eccentric bolt, as shown in FIGS. 13 and 14, and has a threaded portion 56 for attachment to the frame 30 from one end. It consists of a shank 54 that is lightly press-fitted into the inner peripheral surface 42 of the inner ring 41 of the roller 40, a threaded portion 57 for tightening the nut 36, and a prismatic head 59. shank 54
, the tightening screw portion 57 and the prismatic head 59 are eccentric from the mounting screw portion 56 by a dimension d, and by turning the prismatic head 59 with an appropriate tool, the roller 40 can adjust its pivot position. adjusted.

To assemble the bearing assembly 13, first.

The inner ring 4 of the roller 40 is attached to the shank 53 of the first bolt 51.
1 is press-fitted, a washer 37 is inserted into the screw portion 55, and the screw hole 31 on one side of the frame 30 is fixed. Next, the washer 37 is pushed through the second bolt, that is, the inner ring 41 of the roller 40 is press-fitted into the shank 54 of the eccentric bolt 52, and the second bolt is attached to the threaded hole 32 on the other side of the frame 30. Bearing assembly 1 assembled in this way
3 is inserted into the track base 12, and the prismatic head 59 is turned with an appropriate tool to adjust its position so as to generate a preload between the roller 40 and the rod 21. Thereafter, the other roller 40 is fixed with the nut 36.

The linear motion bearing 10 having this structure has no circulating rolling elements, does not require a complicated circulation mechanism, and is compact. In conventional linear motion bearings, the rolling elements roll and move while being elastically deformed between the loaded and unloaded areas, which causes small but undesirable vibrations in the mount, and the return grooves of the rolling elements. On the roads and direction change paths, it was impossible to avoid the generation of abrasion powder due to contact with rolling elements.

In the present invention, since the shaft support roller 40 rolls on the rod 21, such vibrations do not occur, and the pedestal 30 runs smoothly because it is entirely due to rolling contact.

The bearing assembly 13 has four rollers 40 attached to the rod 2.
By being in pressure contact with 1, wobbling in the horizontal direction and in the vertical direction is regulated. Preload is applied from the roller 40 on one side by the eccentric bolt 52, and the recess 45 of the outer ring 43 has a Gothic arch shape. There is two-point contact, which allows the pedestal 30 to resist moment loads about the longitudinal axis of the track 12.

Note that the preload needs to be adjusted within the range of elastic deformation of the rod 21 and roller 40, but can be adjusted freely within that range.

15 to 17 and 18 to 20 respectively show the front seal device 2260 and the side seal device 70. These sealing devices are not required, but are installed when the fIJ4 is used in unfavorable locations such as dusty environments. Note that it is preferable to use a transparent one so that the inside can be seen.

Front seal assembly 2i:60 is a pair of seals 4! l structure 61
61 and a spacer 62. The seal mechanism 61 is
As shown in FIG. 15a, a scraper 63 is attached to the outer circumferential surface of the rod 21 with a slight gap, and a felt-like sealing member 65 is provided on the outer circumferential surface of the rod 21, which is pressed by a spring 64. . This sealing mechanism is symmetrical.

The sealing mechanism 61 has a receiving part 66 that receives the spacer 62, and after receiving the spacer 62 therebetween and fitting each other, the sealing mechanism 61 is fixed to both ends of the bearing assembly 13 by bolts 16. The sealing mechanism 61 is shown in Fig. 16, 1.6.
As shown in Figure a, a check ball type nipple 67 is provided for supplying lubricating oil to the seal member 65. The seal portion +J 65 receives this oil and is impregnated with oil, thereby preventing oxidation of the surface of the polished rod 21 for a long period of time. Symbol>'i681 Indicates a screw hole for mounting the back side sealing device 70.

The side seal device 70 is for dust-proofing the side surface of the bearing assembly 13 and is fixed to the front seal device 60 by bolts 17.

21 to 23 show a stopper 8o provided on the track base 12. FIG. S1 to collar 80 are the bearing assembly 13
It may also be used for positioning. Stopper 8
0 is a gripping member 81, a tightening bolt 82, and a buffer member 83
Consisting of The gripping member 81 is made of aluminum and has #L
A notch 84 is provided on one side of the track base 12, and the first arm 85 and the second arm 86 are engaged with the groove 26 of the track base 12 by inserting it from the end of the track base 12. Then, tighten the tightening bolt 82 to fix it. Yurutabe U83 is Itsuki! It is made of aluminum or rubber, and absorbs the impact of the bearing assembly 13.

The linear motion bearing of this embodiment has the above configuration,
It has a simpler structure and is more compact in height than conventional ones.

Figure 24 shows the track base 12 of Figure 7. Fig. 3b shows a second embodiment of the linear motion bearing 10a of the present invention with a bearing assembly mounted thereon, which is lower in height and more compact than the previous embodiments. The other configurations in this figure are the same as those described above, so their explanation will be omitted.

FIG. 25 shows a linear motion bearing 10b according to a third embodiment of the present invention, in which three rollers 40 are provided on each of the left and right sides of a pedestal 30b. In this way, depending on the load acting on the pedestal, it is sufficient to add the roller 40 or the like that receives the load. In addition, in order to apply appropriate preload to each roller 40, the two bolts that support them are fixed at the rear end on one side.
This is the first bolt 51 shown in FIG. 1, and the other four bolts are eccentric bolts 52 shown in FIG.

FIG. 26 shows a linear motion bearing 10c of the fourth embodiment.
The frame itself is shaped according to the intended use.

Including the embodiment described in 11t1, the shape of the frame is not limited. Unlike in the past, the pedestal does not receive a direct load from the track via the rolling elements, so it simply receives the load from the roller 4.
It is sufficient that a mounting screw hole of 0 is formed, or the screw hole may be provided directly on the table T or the like. roller 40
Since the position of the T is adjusted when preload is applied, the screw holes do not need to be set accurately, and the base of various devices can be used as a stand, and the table T itself as shown in the same figure can be used as a stand. It can also be modified as a stand for the linear motion bearing 10c.

In addition, the present invention does not only have a symmetrical bearing shape as shown in FIGS. ) It goes without saying that by providing a mount having a mount having a mount, it can also be used as a so-called modular linear motion bearing.

Effects of the Invention Since the present invention is configured as described above, it has the following effects.

(1) The track base can achieve the required functionality, lug accuracy, and wear resistance simply by precisely machining the load-bearing rod. Unlike conventional methods, there is no need to process the entire track.

(2) The base of the track is not required to have the above-mentioned functions, and can be made of a lightweight material with low inertia, such as aluminum, which is easy to process.

(3) The bearing assembly does not require a circulation mechanism for the rolling elements, has a simple structure, and receives everything by rolling contact, so it runs smoothly.

(4) Preload to prevent backlash! Since the alignment is performed after the bearing assembly is installed on the track, it is possible to apply an appropriate preload to the linear motion bearing. Shakiness caused by wear after long-term use can also be eliminated by maintaining and adjusting the preload.

(5) The bearing for linear motion, consisting of the track base and bearing assembly, is compact in the height direction, and becomes even more compact when the rollers are directly attached to a linear motion part such as a table.

[Brief explanation of drawings]

The drawings show embodiments of the present invention; FIG. 1 is a perspective view of a linear motion bearing, FIG. 2 is a plan view of FIG. 1, and FIG. 3 is a partial cross-section of the linear motion bearing of FIG. 1. front view, including
Figure 4 is a perspective view of the track. FIG. 5 is a new view of FIG. 4, FIG. 6 is a new view showing a modified example of the wayway, and FIG. 7 is a sectional view showing another modified example of the wayway.
FIG. 8 is a perspective view of the roller, FIG. 9 is a sectional view of FIG. 8, FIG. 10 is a new view showing a modified example of the roller, and FIG. 11 is a first
12 is a side view of 1 in FIG. 11, FIG. 13 is a perspective view of the second bolt (eccentric bolt), and FIG. 14 is a perspective view of the second bolt (eccentric bolt).
The figure is a plan view of Fig. 13, Fig. 15 is a perspective view of a linear motion bearing equipped with a front seal device, Fig. 15a is an exploded perspective view of the seal mechanism, and Fig. 16 is a plan view of the main part of Fig. 15. , Figure 16a is a new view of the lubricating oil supply nipple, 1st
Figure 7 is a front view of Figure 15, Figure 18 is a perspective view of a linear motion bearing equipped with a front seal device and a side seal device, Figure 19 is a side view of Figure 18, and Figure 20 is a side view of Figure 18. 21 is a perspective view of the stopper attached to the track base, FIG. 22 is a partially sectional front view of FIG. 21, and FIG. 23 is a front view of the stopper attached to the track base.
The figure is a side view of FIG. 21, FIG. 24 is a front view of the linear motion bearing of the second embodiment, FIG. 25 is a perspective view of the linear motion bearing of the third embodiment, and FIG. 26 is the fourth embodiment. FIG. 2 is a perspective view of an example linear motion bearing. 4゜・Frame・Roller・Concave・First bolt・Second bolt (eccentric bolt)・Bearing for straight commuting・Railway・Bearing assembly・Base・Rod・Concave Figure n Figure 2 Figure 3 Figure 8 Figure 9 Figure 10 Figure 19 Figure 20 Figure 15 Figure 22 Figure 23

Claims (6)

[Claims] (1) A base having a longitudinally extending recess formed on the side surface;
A track base for a linear motion bearing, comprising a rod fitted and fixed in the recess. (2) The track base according to claim 1, wherein the base is made of aluminum or resin. (3) The track base according to claim 1, wherein the rod is a hardened steel polished rod. (4) A bearing assembly for linear motion comprising a pedestal and a roller pivotally supported on one surface of the pedestal so that a recess formed on the outer circumferential surface abuts the rod of the track base according to claim 1. Three-dimensional. (5) The bearing assembly according to claim 4, wherein the shaft support position of the roller is adjustable by an eccentric bolt. (6) A linear motion bearing comprising the track according to claim 1 and the bearing assembly according to claim 4.