JPS6224653B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is applicable to the table saddle of a machine tool, the sliding surface of a machining center, or the sliding surface of a transport robot that supports a heavy object and moves back and forth. Concerning effective linear motion roller bearings.

(Prior Art) In conventional linear motion roller bearings of this kind, a bearing body with a grooved cross section is slidably mounted on a substantially trapezoidal track with a single cylindrical roller interposed therebetween.

(Problems to be Solved by the Invention) The structure of the conventional example has a drawback that it cannot sufficiently resist loads in the uplift direction and loads in the radial direction.

In addition, since the roller rolling groove that guides the alignment and circulation movement of the cylindrical rollers is formed directly on the inner surface of the skirt portion of the bearing body, the roller rolling groove can be processed by turning, grinding, surface hardening, etc. Not only is the processing work troublesome and inconvenient, resulting in poor work efficiency, but the bearing body must be made of hard and easily quenchable materials, resulting in high material costs and a rise in manufacturing costs. was inviting.

Therefore, the present invention has been made to solve the above-mentioned drawbacks of the prior art, and its purpose is to be able to support loads not only in the floating direction and radial direction, but also in all directions, and to support the rollers. To provide a linear motion roller bearing in which precision machining of rolling grooves and surface hardening treatment can be simply and easily carried out, the workability is good, and the bearing can be manufactured at low cost.

(Means for solving the problems) In order to achieve the above object, the present invention includes the following:
A pair of bearing races is installed in two race storage grooves provided symmetrically in the longitudinal direction on both sides of the inner circumference of the bearing body, and a load roller of the track is attached to the arc-shaped inner circumference of each bearing race. Two rows of loaded roller rolling surfaces are formed facing the rolling surface, and two rows are formed between the two loaded roller rolling surfaces provided on each bearing race and the corresponding loaded roller rolling surface of the way base. interpose a spherical roller,
Moreover, the unloaded roller rolling path formed in the bearing body is arranged on the contact angle direction line of the spherical roller rolling between the loaded roller rolling surfaces.

(Example) Hereinafter, an example of a linear motion roller bearing according to the present invention will be described with reference to the accompanying drawings.

First, a first embodiment of the present invention is shown in FIGS. 1 to 17. In FIGS. 1 to 8, reference numeral 1 indicates the entire bearing body, and this bearing body 1 is made of a block body with a groove-shaped cross section, and is provided with a substantially rectangular central recess 2 at the lower center thereof. At the same time, skirt portions 3 and 4 are provided on the left and right sides of the central recess 2.

On the inside of each skirt portion 3, 4, lace storage grooves 5, 6 having a substantially semicircular cross section are formed symmetrically,
Further, through holes 7 to 10 having a substantially circular cross section and having a diameter larger than the width of the roller are bored in the solid portion of the skirt portions 3 and 4 in the longitudinal direction. As shown in FIGS. 3 and 6, the above-mentioned through holes 7 to 10 are connected to the line of action
Reference line Y-Y making an angle of 30 degrees with respect to the angle of 60
It is located on the intersecting line Z that intersects at a degree.

The bearing main body 1 having the above structure is made of a lightweight material such as synthetic resin, but by having such a lightweight structure, the inertia force can be reduced, so there is a great need for repeating starting and stopping at high speeds. Ideal for linear motion roller bearings.

A pair of left and right bearing races 11 and 12 made of semi-annular cylinder bodies are fitted into the race storage grooves 5 and 6 of the bearing body 1, and the upper and lower ends of these bearing races 11 and 12 are arranged in a plurality of grooves. It is fixedly held by three longitudinally extending retaining plates 11a, 12a fixed to the bearing body 1 by bolts 11b, 12b. As clearly shown in FIGS. 3 and 6, the semicircular inner peripheral surfaces of the bearing races 11 and 12 have load roller rolling surfaces 13 to 1 along the longitudinal direction.
6 is formed. Bearing race 11,1
2 is formed by dividing a cylindrical body made of metal such as steel with high hardness into two parts in the circumferential direction, and performs surface hardening treatment such as induction hardening on the entire inner circumferential surface of the cylindrical body to form loaded roller rolling surfaces 13 to 16. is formed. Therefore, as in the conventional case, the load roller rolling surfaces 13 to 1
Compared to the case where the bearing body 1 is formed by directly grooving the bearing body 1, a loaded ball raceway surface with a high finish accuracy can be manufactured extremely easily.
In addition, in this first embodiment, the load roller rolling surfaces 13 to 16 intersect at an angle of 60 degrees with the reference line Y-Y, which forms an angle of 30 degrees with respect to the line of action X-X of the track 18. They are arranged symmetrically on line Z.

The through holes 7 to 10 of the bearing body 1 include
Tubular body 7a made of synthetic resin, aluminum, etc.
10a is inserted, and each of the tubular bodies 7a to 10a
The outer circumferential shape of is substantially equal to the cross-sectional shape of the through holes 7 to 10, and unloaded roller rolling paths 7b to 10b having a substantially rectangular cross section are formed on the inner circumferential surface thereof. As is clear from FIG. 5, each of the no-load roller rolling paths 7b to 10b and the bearing race 11,
A portion of the inner periphery of the roller 12 between the loaded roller rolling surfaces 13 to 16 is rounded in order to smooth the rolling of the roller. Further, the bearing body 1 is provided with through holes 7 to 10 having a size for inserting the tubular bodies 7a to 10a.
When drilling the through holes 7 to 10, the processing accuracy of the through holes 7 to 10 may be low, so that the work efficiency of the drilling process is high.
Furthermore, by forming the tubular bodies 7a to 10a from synthetic resin or aluminum, which is softer than steel or the like, the noise generated when the rollers roll on the no-load roller rolling paths 7b to 10b in the tubular bodies 7a to 10a can be greatly reduced. can be reduced to

A track 18 is fitted into the hollow recess 2 of the bearing body 1, and is attached to a movable part or a fixed part of a machine tool or the like using fixing means such as bolts. As shown in FIGS. 2, 10 and 11, this track base has left and right protrusions 18a, 1
8b has loaded roller rolling surfaces 19 to 22 extending in the axial direction corresponding to the loaded roller rolling surfaces 13 to 16 of the bearing races 11 and 12, and these both loaded roller rolling surfaces 13 ~16,1
9 to 22 form four linear load roller passages. Furthermore, as shown in FIGS. 1 and 3, the load roller rolling surfaces 19 to 22 of the track base 18 are similar to the load roller rolling surfaces 13 to 16 of the bearing races 11 and 12, as well as the load roller _B1. The contact angles β ₁ and β ₂ (the angle between the reference plane P perpendicular to the vertical central axis O of the bearing body and the contact angle direction line l of the load roller B) with the load roller rolling surfaces 19 to 22 are respectively 90 degrees and 30 degrees.

B is a barrel-shaped spherical roller that is interposed between the bearing races 11, 12 and the track 18 and moves in circulation; Load roller that is loaded by rolling inside
B ₁ , a no-load roller rolling within the no-load roller rolling paths 7b to 10b of the bearing body 1;
Contains _B2 . Note that the difference between the loaded roller B ₁ and the unloaded roller B ₂ merely indicates whether the same roller is rolling in a loaded region or in a non-loaded region. Also,
The curvature of the spherical outer surface of the roller B is slightly larger than the curvature of the arc-shaped loaded roller rolling surfaces 19 to 22.

Reference numerals 23 and 24 denote side covers that are attached to the front and rear end surfaces of the bearing body 1 by fixing means such as bolts, and are manufactured by injection molding or die casting using synthetic resin material or die casting alloy. According to FIGS. 14 to 17,
The structure of the side lids 23 and 24 will be explained with reference to one of the side lids 23. The side lid 23, which is a lid body with a generally groove-shaped cross section, is provided with a generally rectangular hollow recess 25 in the center thereof. By providing skirt portions 26 and 27 on the left and right sides of the hollow recess 25, and at the same time forming left-right symmetrical grooves 28 and 29 on the inner peripheral edge of each skirt portion, the above-mentioned It has a shape similar to the inner peripheral shape of the bearing body 1. Furthermore, the side lid 23 has a roller direction conversion groove 3 that is curved in the inner surface of the lid toward the outer surface of the lid.
0a', 30a'' and 30b', 30b''. The respective roller direction conversion grooves 30a', 30a'' and 30b',
30b" in more detail, as shown in FIG. It is placed on the intersection line Z,
It extends along the intersection line Z for a predetermined length. Therefore, each roller direction conversion groove 30a', 30a'', 30
The starting ends of b', 30b'' are bearing races 11, 12
and load roller rolling surface 13 to 1 of track base 18
6, 19 to 22, and its terminal end corresponds to the groove ends of the no-load roller rolling paths 7b to 10b of the bearing body 1.

In short, each roller direction conversion groove 30a', 30
a'' and 30b', 30'' have their starting ends communicated with the loaded roller rolling surfaces 13-16, 19-22, and at the same time their terminal ends communicate with the unloaded roller rolling paths 7b-10b. There is. Therefore, by the side cover 23 provided with this roller direction conversion groove, the front sides of the loaded roller rolling surfaces 13 to 16, 19 to 22 and the unloaded roller rolling paths 7b to 10b, which are in a mutually corresponding relationship, are connected. Ru. On the other hand, the loaded roller rolling surfaces 13 to 16, 19 to 22 and the other side of the unloaded roller rolling paths 7b to 10b are connected by another side cover 24 having the same configuration as the one side cover 23 described above. For example, a roller circulation path is formed by any loaded roller rolling surfaces 13, 19 and any unloaded roller rolling paths 7b to 10b (see FIG. 5).

33 and 34 are locking grooves provided on the inner surface of the side cover 23 and having the same cross-sectional shape as the retainer to be described later;
These locking grooves 33, 34 are formed in the U-shaped portion of the roller direction conversion grooves 30a', 30a'', 30b',
It is formed to cross the starting end of 30b''.
Race holding grooves 31 and 32 and locking grooves 33 and 34 having the same structure are also provided on the inner surface of the other side cover 24.

Reference numerals 35 and 36 denote a pair of left and right retainers that guide the rolling transition of the load balls _B1 , and curve the strip steel plate into an arc shape along the inner peripheral surfaces of the bearing races 11 and 12, as well as a cross section along the longitudinal direction. Approximately U-shaped roller holding parts 35a, 36a are formed by bending, and the bottom surfaces of the roller holding parts 35a, 36a are provided with slits 3 to the extent that the roller B does not fall off.
At the same time that 5b and 36b are formed, tongue pieces 35c and 36c are formed at both ends of these slits. These tongue pieces 35c, 36c scoop up the rollers that have rolled on the loaded roller rolling surfaces 13-16, 19-22, and then transfer them to the ball direction conversion grooves 30a', 30a'' and 30b', 30b. This function is to feed the roller into the inside of the roller and smoothly change the direction of the roller from the linear direction to the rotational direction. Further, the roller holding parts 35a, 36a have a pair of side walls 35d, 35d; 36d, 36d which are arranged opposite each other at an interval substantially equal to the width of the roller B. These side walls 35d, 35d; 36d, 36
d guides the rolling motion of roller B and prevents its skew (center shaft wobbling). Both ends of these retainers 35, 36 are engaged with the locking grooves 33, 34, . . . of the side covers 23, 24, thereby being fixed to the side covers 23, 24. As mentioned above, these tongue pieces 35c, 3
6c has the function of guiding the roller from the linear direction to the rotational direction, so its strength and rigidity are very important. Therefore, the retainers 35 and 36 are given rigidity by being subjected to heat treatment such as Tufftride treatment. is desirable.

Then, when the retainers 35 and 36 are inserted into the bearing main body 1 and both ends thereof are fixed with the side covers 23 and 24, the center axes of the slits 35b and 36b and the load roller rolling surfaces 13 to 16, 19 to 2
It is assumed that the central axes of the two are on the same straight line.

To explain the operation of the present invention having the above configuration, for example, a machining center (not shown)
After incorporating the linear motion bearing unit of the present invention into the track base 18 and setting the required machinery on the bearing body 1, when the bearing unit is moved forward and backward, the bearing races 11, 12
The load roller _B1 , which is held between the load roller rolling surfaces 13 to 16 and 19 to 22 of the track base 18, travels in one direction while being prevented from skewing by the retainers 35 and 36. Eventually, the load roller B ₁ is scooped up by the tongues 35c and 36c on one side of the retainers 35 and 36, and then moved into the roller direction conversion grooves 30a' and 30a'' of the side cover 24.
b', 30b'', the direction is changed from the linear direction to the rotational direction, and the unloaded ball is sent into the unloaded roller rolling paths 7b to 10b of the bearing body 1.
B becomes ₂ . At this time, since each roller direction changing groove is formed along the contact angle direction line l of the loaded roller _B1 , the direction changing of the loaded roller _B1 is carried out extremely smoothly without causing sideways slipping or the like. After that, the no-load roller rolling paths 7b to 10
The no-load roller B ₂ that has run inside the roller direction converting grooves 30a' and 3 formed in the side cover 23 on the opposite side
0a'', 30b', 30b'', the direction is changed from the linear direction to the rotational direction, and the bearing races 11, 12 and the loaded roller rolling surface 1 of the track 18 are again
Returns to 3-16, 19-22, loaded ball
B becomes ₁ . Thereafter, the alignment cycle is repeated for the same operation.

In the above embodiment, the case where the no-load roller rolling paths 7b to 10b are formed by the inner circumferential surfaces of the tubular bodies 7a to 10a has been described, but the no-load roller rolling paths 7b to 10b are formed by the bearing body 1.
It may also be formed by drilling in a straight line.

FIG. 18 shows a second embodiment of the present invention,
The same members as in the first embodiment are given the same reference numerals. In this embodiment, the bearing race 11,
12 and the loaded roller rolling surface 13 of the wayway 18
~16, 19~22 are lines of action on the track 18 X-
They are arranged symmetrically on the intersecting line Z' that intersects X at an angle of 45 degrees, and _{the contact angles β 1 ,} β ₂ ( The angle between the reference plane P perpendicular to the vertical central axis O of the bearing body 1 and the contact angle direction line l' of the load roller B is approximately 45 degrees.
In addition, through holes 7 to 7 bored in the bearing body 1
10 is located on the intersection line Z'. Then,
In this embodiment, loaded roller rolling surfaces 13 to 1
Load roller B ₁ interposed between 6, 19 and 22
Since the contact angle is set to approximately 45 degrees, it can equally support not only loads in the floating direction and radial direction, but also loads from all directions. The structure and operation of this embodiment other than those described above are substantially the same as those of the first embodiment.

(Effects of the Invention) The present invention has the above-described configuration and operation, and since the bearing race having the loaded roller rolling surface is formed separately from the bearing body, the loaded roller rolling surface is formed directly on the bearing body. This not only makes it easier to perform surface hardening treatments such as grinding and quenching on the rolling surface of the loaded rollers, which not only greatly improves the efficiency of these operations, but also significantly improves machining accuracy and improves reliability. A thermosetting treatment can be carried out to improve the wear resistance of the loaded roller rolling surface, thereby ensuring smooth aligned circulation of the roller over a long period of time. In addition, only the bearing race needs to be made of a relatively expensive material that is easy to grind and surface harden, and the bearing body itself can be made of inexpensive material, making it possible to reduce the cost of the entire roller bearing. Furthermore, since the bearing race is formed into a semi-annular shape with high torsional resistance, the bearing race does not twist even when a load is applied, and as a result, the contact pressure of the rollers rolling along the bearing race is uniform. Since it can be held, it prevents the roller from skewing and enables its smooth alignment and circulation. Furthermore, since a part of the arc-shaped inner circumferential surface of the bearing race is used as the load roller rolling surface, there is a possibility that the formation position of the load roller rolling surface may be misaligned, and the bearing body and the track base may be attached to the table or bed. surface parallelism error,
Even if the machine body to which the bearing is attached is twisted or deformed due to a heavy load, the automatic adjustment action of the spherical roller will ensure that the spherical roller remains in position over its entire length against the bearing body and the loaded roller rolling surface of the track base. The rollers are in line contact with each other, so they can easily withstand large loads and roll smoothly, greatly extending the life of the roller. In addition, the left and right 2
The rows of spherical rollers can sufficiently support not only loads in the floating direction and radial direction, but also loads from all directions (especially loads in the vertical direction).
Furthermore, since the unloaded roller raceway formed in the bearing body is placed on the contact angle direction line of the roller rolling on the loaded roller raceway surface, the roller can move from the loaded roller raceway surface to the unloaded roller raceway, or When moving in the opposite direction, the direction of movement can be smoothly changed without causing sideslip, etc. Therefore, no excessive load is applied to the rollers, and the durability of the rollers can be significantly improved. It is something.

[Brief explanation of the drawing]

The figures show an embodiment of a linear motion roller bearing according to the present invention, and FIGS. 1 to 17 show the first embodiment of the present invention. FIG. 1 is an overall front view, and FIG. 2 is an overall side view. Figure, Figure 3 is Figure 2-
Line sectional view, Figure 4 is line sectional view, Figure 3 - Line sectional view, Figure 5.
The figures are a sectional view taken along the line shown in FIG. 3, a front view of the bearing body, FIG. 7 a plan view of the bearing body, a sectional view taken along the line taken in FIG. 8, and a longitudinal cross-section of the tubular body. 10 is a front view of the tubular body, FIG. 11 is a front view of the retainer, FIG. 12 is a side view of the retainer, FIG. 13 is a sectional view taken along the line of FIG. 12,
FIG. 14 is a plan view of the side cover, FIG. 15 is a front view of the side cover, FIG. 16 is a sectional view taken along the line of FIG. 15, FIG. 17 is a sectional view taken along the line of FIG. FIG. 4 is a sectional view similar to FIG. 3, showing a second embodiment of the invention; 1...Bearing body, 2...Central recess, 3,
4...Skirt part, 5, 6...Lace storage groove, 7
~10...Through hole, 7a-10a...Tubular body, 7
b~10b...No-load roller rolling path, 11,1
2...Bearing race, 13-16, 19-2
2... Load roller rolling surface, B... Roller,
l, l'...Roller contact angle direction line.

Claims (1)

[Claims] 1. A linear motion bearing in which a bearing body having left and right skirts sandwiching a central recess is slidably fitted to a track via rollers,
A pair of semi-annular bearing races are respectively installed in two race housing grooves provided symmetrically in the longitudinal direction on both sides of the inner periphery of the bearing body, and the Two loaded roller rolling surfaces are formed facing the loaded roller rolling surface of the wayway, and two loaded roller rolling surfaces provided on each bearing race and the corresponding loaded roller rolling surface of the wayway are formed. Two rows of spherical rollers are interposed between the surfaces, and the unloaded roller rolling path formed in the bearing body is arranged on the contact angle direction line of the spherical roller rolling between the loaded roller rolling surfaces. Features linear motion roller bearings. 2. Forming four through holes extending in the longitudinal direction on the contact angle direction line of the roller in the bearing body, and inserting a tubular body having the no-load roller rolling path on the inner peripheral surface into each of the through holes. A linear motion roller bearing according to claim 1.