JPS6353312A - Multi-row roller bearing - Google Patents

Abstract

PURPOSE:To obtain a multi-row roller bearing with high reliability by forming a spherical surface, whose center of curvature coincides with the center of bearing, on the raceway track surface of outer ring in each row of rollers among more than four rows, and arranging spherical rollers thereon, thereby equalizing the load distribu tion to each row of rollers. CONSTITUTION:The first to fourth raceway grooves 13 to 16 are formed on the outer circumferential surface of an inner ring 10 in a form of circular arc with the same length of a generating line. An outer ring consists of outside outer rings 21, 22, pro vided on both ends in the axial direction and an inside outer ring 20 between them. The first and fourth raceway track surfaces 23, 26, corresponding to the first and fourth raceway grooves 13, 16 on the inner ring 10 are formed on the inner circumferen tial surfaces of the outside outer rings 21, 22, respectively. The second and third race way track surfaces 24, 25, corresponding to the second and third raceway grooves of the inner ring 10 are formed on the inner circumferential surface of the inside outer ring 20. All the surfaces mentioned above form a spherical surface of radius R whose center of curvature coincides with center of bearing O. Even if each row of rollers is subjected to an uneven load, therefore, the spherical rollers are brought in normal contact with the outside raceway track surface so that the distribution of load is equalized.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to multi-row roller bearings, and particularly in multi-row roller bearings in which uneven loads are applied to each roller row, it is possible to equalize the load on each roller row. This is designed to extend the life of the bearing.

[Prior Art] In general, multi-row roller bearings are widely used as bearings for roll necks such as rolls of rolling mills and back-amp rolls. A four-row tapered roller bearing as shown in Figure 3 is installed. In the figure, reference numeral 1 indicates a roll of a rolling mill, and reference numeral 2 indicates a roll neck. Four-row tapered roller bearings 4 that support the roll neck 2 in the radial direction are held by a bearing box (chock) 3.

This tapered roller bearing 4 has four rows of tapered rollers 8 assembled between two double-row inner rings 5, two single-row outer rings 6, and one double-row outer ring 7. The tapered rollers 8 have the same specifications in material, shape, and dimensions in each roller row, and are arranged in the same number. In addition, the bearing box 3 has a bearing member 9.
It is supported via a support member 9b that contacts the roll 1 on a curved surface, and is provided with an alignment mechanism that allows the bearing box 3 to follow the deflection of the roll 1 and tilt. Furthermore, recent rolling mills have been developed that are equipped with a mechanism that moves the roll 1 in the axial direction. When it moves, a moment load is applied that is deviated from the center of the bearing.

[Problem that the invention seeks to solve]

As mentioned above, in a roll neck bearing equipped with an alignment mechanism for the bearing box 3, if the alignment mechanism operates normally, the relative inclination between the axis of the roll 1 and the central axis of the bearing box 3 will be Since this does not occur, an equal load is applied to each roller row of the bearing, but in reality, the bearing of the alignment mechanism is affected by the frictional force between the member 9a and the support member 9b, etc. As a result, the bearing box 3 often does not follow the inclination of the roll 1 sufficiently, and a situation occurs in which the center axis of the bearing box 3 receives a load in a state where it does not coincide with the axis of the roll (2).

Therefore, as shown in Figure 4, the load on each roller row is large, even though a large load is applied to a specific roller row (row B, the second row from the barrel side, and row D, the fourth row from the barrel side). On the other hand, the load applied to the other rows A and 0 becomes smaller, resulting in a very uneven load distribution for the bearing as a whole. As a result, on roller rows that are subjected to large loads, loads exceeding the rated load are applied, edge loading occurs, and early exposure causes damage such as smearing, making the life time of each roller row uneven. There is a problem.

Furthermore, if a mechanism for moving the roll 1 in the axial direction is provided, an uneven load distribution will occur as shown in FIGS. 5 and 6. That is, Fig. 5 fa)
When the load center P deviates toward the barrel side with respect to the axial center WOO of the bearing due to the axial movement of the roll L, as shown in the same figure ('b), the load in the B row is However, on the contrary, if the load center P deviates toward the shaft end side with respect to the axial center position O-O of the bearing as shown in Fig. 6(a), ), the load on the 0th row is the maximum.

Therefore, especially in roll neck bearings of rolling mills equipped with a roll moving mechanism, roll deflection and moment loads make the load distribution of each row of rollers increasingly uneven, leading to early bearing failure. The result is that it helps.

This invention was made to solve the above problems, and an object of the invention is to provide a multi-row roller bearing in which an equal load is applied to each row of rollers.

[Means for Solving the Problems] The multi-row roller bearing of the present invention is a bearing having at least four rows of rollers arranged between an inner ring and an outer ring, and each roller row has a spherical surface. Rollers are arranged, and the raceway surface of the outer ring of each roller row is formed with a spherical surface whose center of curvature coincides with the center of the bearing.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is an enlarged vertical sectional side view showing only the upper half of the bearing portion when the present invention is applied to the roll neck bearing of the rolling mill shown in FIG. 3.

In the bearing shown in the figure, the inner ring 10 is a four-row inner ring in which the first to fourth rows of raceway grooves are integrally provided, but the outer ring consists of outer outer rings 21 and 22 at both ends in the axial direction and an inner outer ring 20 in the center. ,
The outer outer rings 21 and 22 are single-row outer rings having raceway surfaces in the first and fourth rows, respectively, and the inner outer ring 20 is a double-row outer ring in which raceway surfaces in the second and third rows are integrally provided. The outer outer rings 21 and 22 and the inner outer ring 20 are assembled with their opposing end surfaces facing each other. This outer outer ring 2
1.22 and the inner and outer ring 20 have semicircular oil fillers 27a, 28a; 27b on their opposing end faces, respectively.

A plurality of oil fillers 28b are provided in the radial direction at intervals in the circumferential direction, and these oil fillers 27a, 28a;
8b are aligned to form a perfect circular oil filler at 27° and 28°.

Further, the inner outer ring 20 is provided with a plurality of oil fillers 29,
Oil supplied through these oil containers 27, 28, 29,
The inside of the bearing is lubricated using a lubricant such as grease.

On the outer circumferential surface of the inner ring 10, small flanges 10b and 10c are provided at equal intervals on both sides in the axial direction of the middle rib 10a at the center, and small flanges 10c and 10b on the left side in the axial direction.
1 through the middle brim 10a to the small brim 10b on the right side in the axial direction.
Between each rib extending to 0c, a first orbit groove 13, a second orbit groove 14, a third orbit groove 15, and a fourth orbit groove 16 are formed in an arc shape with the same generatrix length.

Also, on the inner circumferential surface of the outer outer ring 21, 22, first raceway surfaces 23. A fourth raceway surface 26 is formed.

The first raceway surface 23 and the fourth raceway surface 26 are located at the bearing center 0.
It is a spherical surface with radius R and center of curvature. Similarly, a second raceway surface 24 and a third raceway surface 25 corresponding to the second raceway groove 14 and third raceway groove 15 of the inner race 10 are formed on the inner peripheral surface of the inner outer ring 20 . The second raceway surface 24 and the third raceway surface 25 have a radius R with the center of curvature at bearing center 0.
is a spherical surface, and its axially opposite end edges are the outer outer ring 21.
The first raceway surface 23 and the fourth raceway surface 26 of 22 are smoothly connected to the axially opposite end edges thereof.

The above inner ring 10, outer outer ring 21, 22 and inner outer ring 2
0, there is an asymmetrical spherical roller 30 having the same shape.
are arranged in the first to fourth rows of rollers.

These spherical rollers 30 are held and guided by a machined cage 32, but a pin-shaped or pressed cage, a synthetic resin cage, or the like may also be used as required.

In the bearing with the above configuration, the first to fourth raceways of each outer ring are connected to the surface 2.
3, 24, 25, and 26, there is provided a self-aligning roller bearing having four rows of rollers each having a spherical surface whose center of curvature coincides with the bearing center 0, in which each row of spherical rollers 30 is connected to its respective outer ring raceway. It contacts surfaces 23, 24, 25, and 26 and receives a load.

Therefore, when this bearing is installed and used in the roll neck of a rolling mill, even if an uneven load is applied to each row of rollers due to the inclination of the bearing box or deflection of the roll, each row of rollers will be Since the spherical rollers make normal contact, the load distribution becomes even and damage caused by edge loading can be prevented.

FIG. 2 is a sectional view of the upper half of the housing showing another embodiment of the present invention.

In this embodiment, the inner ring is the outer inner ring 11.1 at both ends in the axial direction.
2 and a central inner inner ring 10, and an outer inner ring 11.1.
Reference numeral 2 denotes a single-row inner ring of the same width having raceway grooves in the first and fourth rows, and the inner inner ring 10 has raceway grooves in the second and third rows.
It is a double-row inner ring with integral rows of raceway grooves, and is assembled with mutually opposing end surfaces abutting each other.

The outer ring similarly consists of an outer outer ring 21.22 and an inner outer ring 20, and the outer outer ring 21.22 is a single-row outer ring having the same width and the raceway surfaces of the first row and the fourth row, respectively, and the inner outer ring 2
0 is a double-row outer ring in which the raceway surfaces of the second row and the third row are integrally provided, and the outer outer ring 2L22 and the inner outer ring 20 have outer ring spacers 40 and 42 interposed between their opposing end surfaces, respectively. It is assembled. This outer ring spacer 40.42 is provided with a plurality of oil fillers 41.43. Also, inner outer ring 2
0 is also provided with a plurality of oil containers 44.

On the outer peripheral surface of the outer inner ring 11, 12, a 12th raceway groove 13° and a 4th raceway groove 16 are formed on the same generatrix between the large ribs lla, 12a on the large diameter side and the small ribs 11b, 12b on the small diameter side, respectively. It is formed by length. On the outer circumferential surface of the inner inner ring 10, a second raceway groove 14 and a third raceway groove whose generatrix length is longer than the first and fourth raceway grooves 13 and 16 are formed between the middle rib 10a and the small ribs 10b at both ends in the axial direction. The track groove 15 is formed with the same generatrix length.

Further, the first raceway grooves 13. of the outer inner rings 11.12 are formed on the inner peripheral surfaces of the outer outer rings 21.22, respectively. 4th orbit groove 16
The first raceway surface 23.corresponding to the first raceway surface 23. A fourth orbit 26 is formed. The first raceway surface 23 and the fourth raceway surface 26 are spherical surfaces having a radius Ra with the bearing center O as the center of curvature. Similarly, on the inner circumferential surface of the inner outer ring 20, the second
A second raceway surface 24 and a third raceway surface 25 are formed corresponding to the raceway groove 14 and the third raceway groove 15. This second
The raceway surface 24 and the third raceway surface 25 are spherical surfaces with the center of curvature at the bearing center O, but the radius of curvature Rb is smaller than the radius of curvature Ra of the first raceway surface 23 and the fourth raceway surface 26. ing.

Between the outer inner rings 11 and 12 and the outer outer rings 21 and 22, a first asymmetrical spherical roller 30a having the same shape is provided.
Asymmetrical spherical rollers 30b having the same shape and dimensions are arranged between the inner inner ring 10 and the inner outer ring 20 as the second and third rows of rollers. ing.

The maximum diameter of the spherical rollers 30b in the second and third rows is the same as that of the spherical rollers 30a in the first and fourth rows, but the length dimension is greater than that of the spherical rollers 30a in the first and fourth rows. It's also getting longer.

These spherical rollers 30a, 30b are connected to a pin-shaped cage 33.
In addition to this, a machined or pressed cage, a synthetic resin cage, or the like may be used as necessary.

In this embodiment as well, the self-aligning roller bearing has four rows of rollers in which the center of curvature of the spherical surface formed on the first to fourth raceway surfaces 23.24, 25.26 of each outer ring coincides with the bearing center O. It will be configured as

According to this embodiment, even if there are restrictions on the width and external dimensions of the bearing, or even in bearings with large width dimensions, the raceway surface of each row of rollers in the outer ring can be formed into a spherical surface whose center of curvature coincides with the center of the bearing. and the second and third rows
Since spherical rollers having a longer length dimension than the other roller rows can be arranged in each row, the load capacities of the second and third rows are larger than those of the other roller rows.

In each of the embodiments described above, a case has been described in which the present invention is applied to a roller bearing with four rows, but the present invention can be similarly applied to a roller bearing with five or more rows.

In addition, in the above embodiment, an example using asymmetric spherical rollers was explained, but bearing designs using symmetric spherical rollers or a combination of asymmetric spherical rollers and symmetric spherical rollers may also be used. It may also be implemented. Furthermore, the length of the spherical rollers in each roller row is not limited to that in the embodiment, and spherical rollers of appropriate lengths are selected and used depending on the usage conditions.

〔Effect of the invention〕

As explained above, the multi-row roller bearing of the present invention has a self-aligning roller bearing in which spherical rollers are arranged by forming a spherical surface whose center of curvature coincides with the bearing center on the outer ring raceway surface of each of the four or more roller rows. Since it is configured as a roller bearing, even if the shaft is deflected or the bearing box is tilted, an equal load is applied to each row of rollers, and the life span of each row of rollers is averaged, which improves the bearing as a whole. It becomes possible to obtain a multi-row roller bearing with a long life and high reliability.

Therefore, the multi-row roller bearing of the present invention is a bearing having the most suitable performance for the roll neck of a rolling mill.

[Brief explanation of the drawing]

FIG. 1 is a sectional side view of an upper half showing an embodiment of the invention, FIG. 2 is a sectional side view of an upper half showing another embodiment of the invention,
Fig. 3 is a vertical side view showing a conventional example of a roll neck bearing for a rolling mill, Fig. 4 is a load distribution diagram of each roller row of a roll neck bearing, and Figs. 5 and 6 are roll moving type rolling. Figure 5 (al) and Figure 6 (a) are load center position diagrams, respectively.
FIG. 5fbl and FIG. 6(b) are load distribution diagrams for each roller row, respectively. In the diagram, 10.11.12 is the inner ring, 13.14°15.1
6 are the first raceway groove, the second raceway groove, and the third raceway groove of the inner ring, respectively.
Raceway groove, 4th orbit groove, 20°21.22 is outer ring, 2
3, 24, 25.26 are the first raceway surface, second raceway surface, third raceway surface, fourth raceway surface, and 30.26 of the outer ring, respectively. 30 a
, 30 b is a spherical roller, R, Ra, and Rb are radii of curvature of the outer ring raceway surface, and 0 is the center of the bearing. Figure 1 Figure 2 Figure 3 a Figure 4 Figure 5 Row Figure 6 (Q) (b) A BCD Row

Claims (4)

[Claims] (1) In a multi-row roller bearing in which at least four rows of rollers are arranged on the raceway surface between the inner ring and the outer ring, spherical rollers are arranged in each roller row, and the outer ring raceway surface of each roller row has a curvature. A multi-row roller bearing characterized by having a spherical surface whose center coincides with the bearing center. (2) A multi-row roller bearing according to claim 1, wherein a spherical surface with an equal radius of curvature is formed on the outer ring raceway surface of each roller row. (3) A spherical surface having a radius of curvature larger than the radius of curvature of the outer ring raceway surfaces of the other roller rows is formed on the outer ring raceway surfaces of the first and last roller rows. Multi-row roller bearings as described in section. (4) The roller system according to claim 3, wherein each roller row other than the first row and the last row is provided with a spherical roller that is longer than the length of the spherical rollers in the first row and the last row. Row roller bearing.