JPS61175312A - Multiple-row roller bearing device - Google Patents

Abstract

PURPOSE:To equalize load distribution of each roller row so as to prevent damage at an early stage by minimizing rigidity of a circular part for a roller row where large load is laid or that of the roller on the roller row. CONSTITUTION:A concave groove 14a having a bottom surface at taper angle parallel to the truck surface is formed on the bore diameter surface of a circular part for a roller row 13 of an inner wheel 14, and so is a concave groove 15a on a circular part for a roller row D of an inner wheel 15. Similarly, a concave groove 17 having a bottom surface at taper angle parallel to the truck surface is formed on the major diameter surface of a circular part for a roller row B of an outer wheel 17, and so is a concave groove 18 on a circular part for a roller row D of on outer wheel 18. As the result, rigidity of the circular part for the rows B, D becomes smaller than that for the roller rows A, C, and load of each roller row is equalized.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a multi-row roller bearing device, and in particular, in a multi-row roller bearing device in which uneven loads are applied to each roller row, small loads are applied. By reducing the rigidity of the bearing parts, rotating shaft, and bearing housing of the roller rows that are subject to large loads, the load on each roller row can be brought closer to equalization. be.

[Conventional technology]

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 is installed. In the figure, reference numeral 10 indicates a roll of a rolling mill, and reference numeral 11 indicates a roll neck. Four-row tapered roller bearings 12 that support the roll neck 11 in the radial direction are held by a bearing box (ticket) 22. This tapered roller bearing 12 has two double-row inner rings 14.
15, two single row outer rings 16.1B, one double row outer ring 17
Four rows of tapered rollers 20 are assembled between the rollers, and each row of tapered rollers 20 has the same specifications in material, shape, and dimensions, and has the same number of rollers. . Further, the bearing box 22 is supported via a support member 31 that contacts the receiving member 30 on a curved surface, and is provided with an alignment mechanism that allows the bearing box 22 to tilt following the deflection of the roll 10. ing. Furthermore, recent rolling mills have been developed that are equipped with a mechanism for moving the rolls 10 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 22, if the mechanism of interest operates normally,
Since there is no relative inclination between the axis of the roll 10 and the center axis of the bearing box 22, an equal load is applied to each roller row of the bearing. Due to the influence of frictional force between the receiving member 30 and the supporting member 31, the bearing box 22 often does not follow the inclination of the roll 10 sufficiently, and the central axis of the bearing box 22 is A situation occurs in which a load is applied without being aligned with the axis. For this reason, the load on each roller row is, for example, as shown in Fig. 6, even though a large load is applied to a specific roller row (row B, which is the second row from the barrel side, and row D, which is 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, large edge loads occur, and early exposure can cause damage due to smearing, etc., and the lifespan of each roller row becomes uneven. There is a problem with becoming.

Further, if a mechanism for moving the roll 10 in the axial direction is provided, an uneven load distribution will occur as shown in FIGS. 7 and 8.

In other words, when the load center P deviates toward the barrel side with respect to the axial center position 0-0 of the bearing due to the axial movement of the roll 10 as shown in FIG. 7(a), As shown, the load on the B row is the largest, but on the contrary, the 8th row
When the load center deviates toward the shaft end side with respect to the axial center position O-0 of the bearing as shown in FIG.

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-mentioned problems, and an object of the invention is to improve the relative stiffness of a roller row to which a large load is applied to a roller row to which a small load is applied. It is an object of the present invention to provide a multi-row roller bearing device in which the load on each roller row is equalized.

[Means for solving problems]

Under operating conditions in which multiple rows of rollers are arranged on the raceway between the inner ring fitted on the rotating shaft and the outer ring held in the bearing box, and different loads are applied to each roller row. In a multi-row roller bearing device, the inner ring.

Among at least one part of the outer ring 1 rotating shaft and the bearing box, the rigidity of the annular part corresponding to the roller row to which a large load is applied, or the annular part corresponding to the roller row to which a large load is applied, among the annular parts corresponding to each roller row. The rigidity of the rollers in the roller row is made smaller than the rigidity of the annular portion corresponding to the roller row on which a small load is applied, or the rigidity of the rollers in the roller row on which a large load is applied. contact length with respect to the raceway surface,
At least one of the diameter and the number of rollers is smaller than the diameter and the length of contact with the raceway surface of the rollers of the roller row to which a small load is applied, and is smaller than the number of rollers.

〔Example〕

Hereinafter, an embodiment in which the present invention is applied to a roll neck bearing under the usage conditions shown in FIG. 5 will be described.

1 shows a first embodiment of the present invention, in which a four-row tapered roller bearing is used as a roll neck bearing, similar to the conventional example.

In this figure, the assembly structure of each part of the roll, roll neck, four-row tapered roller bearing, and bearing box is the same as in the above-mentioned Fig. 5, so the same parts are given the same reference numerals and detailed explanations will be given. omitted.

Among the parts constituting the four-row tapered roller bearing 13, the tapered rollers 20 have the same diameter and the same length in each roller row, and the same number of rollers are arranged in each row.

In the inner ring 14, a concave groove 14a having a bottom surface with a taper angle parallel to the raceway surface of the row is provided on the inner diameter surface of the annular portion corresponding to the second row of rollers from the barrel side (row B). It is formed continuously in the circumferential direction with almost the same axial length,
Also on the inner diameter surface of the inner ring i5, there is a fourth row of rollers on the barrel side (
A groove 15a having a similar shape to the groove 14a is formed in the annular portion corresponding to the row D).

Further, in the outer ring 17, a concave groove 17a having a bottom surface with a taper angle parallel to the raceway surface of the row is formed on the outer diameter surface of the annular portion corresponding to the B row, and has a length in the axial direction that is approximately the same as the raceway surface. A groove 18a having a similar shape to the groove 17a is also formed on the outer diameter surface of the outer ring 18 in an annular portion corresponding to the D row.

By configuring as described above, the rigidity of the annular portion corresponding to the A row of the inner ring 14 (the first roller row from the barrel side) and the 0 row of the inner ring 15 (the third roller row from the barrel side) is increased. , the rigidity of the annular portion corresponding to the B row of the inner ring 14 and the D row of the inner ring 15 becomes smaller.
The rigidity of the annular portion corresponding to the B row of the outer ring 17 and the D row of the outer ring 18 is smaller than the rigidity of the annular portion corresponding to the row B of the outer ring 17 and the row D of the outer ring 18.

In the rolls of a rolling mill equipped with the four-row tapered roller bearing device configured as described above, the load distribution applied to each roller row becomes uneven due to the deflection and moment load of the roll, and the difference between rows B and D It is assumed that a larger load is applied to the roller rows than the roller rows of the A row and the 0 row.

Inner rings 14 corresponding to rows B and D, which are loaded with large loads.
Concave grooves 14a, 15a and concave grooves 17a, 18a are formed in the annular portions of the outer rings 15 and 17, 18, respectively, and these concave grooves 14a, 15a; As flexural deformation occurs, the load is distributed and the load is reduced.
The load is applied to the annular portions of the outer rings 16 and 17, and the load on the annular portions of the row increases. Therefore, the loads on each roller row function in the direction of equalization.

In the above embodiment, the case where the grooves are formed in both the inner ring and the outer ring is explained, but the grooves may also be formed in either the inner ring or the outer ring. Similar effects can be obtained.

Furthermore, the grooves are not limited to being formed continuously around the entire circumferential direction of the annular portion corresponding to the roller example of the characteristics of the inner ring and the outer ring, but can also be formed in a portion or in a discontinuous manner. ,
You can obtain the same effects as Habo.

FIG. 2 shows a second embodiment of the invention. In this embodiment, an annular portion (a part of the outer circumferential surface) of the outer circumferential surface of the roll neck 11 corresponding to rows B and D has an axial length and a constant depth that are approximately the same as the raceway surfaces of the rows. A groove 11a and a groove 11b having the bottom surface of the groove are formed continuously in the circumferential direction, and the bearing box 22 also has an annular portion (a part of the bore) corresponding to the B row and the D row. A groove 22a and a groove 22b having a bottom surface having substantially the same axial length as the raceway surface of the row and a constant depth are formed continuously in the circumferential direction on the inner circumferential surface of the groove.

In this way, by releasing a part of the fitting surface of the bearing rings, the rigidity of the bearing rings corresponding to the B row and D row can be made smaller than the rigidity of the bearing rings corresponding to the A row and the 0 row. do. That is, in the annular portions of the roll neck 11 and bearing box 22 corresponding to rows B and D, which are loaded with large loads, the bearing rings are deflected and deformed to reduce the load, and a small load is loaded. By increasing the loads on the A and 0 rows, it is possible to equalize the loads on each roller row.

In this embodiment as well, the groove may be formed in either the roll neck or the bearing box (the groove may be formed in a part of the circumference or discontinuously).

FIG. 3 shows a third embodiment of the invention. In this embodiment, the inner ring 14°15 and the outer ring 1 of the 4-row tapered roller bearing 13 are
The configuration of 6.17.18 is the same as the conventional bearing, but solid rollers 20a and 20c are arranged in the roller rows A and 0, which carry small loads, and which carry large loads. The solid rollers 20a, 20 are placed in the loaded roller rows B row and D row.
Hollow rollers 20b and 20d having the same outer diameter as c are provided.

With this configuration, there is a difference in the rigidity of the tapered rollers in each row of rollers, and the rigidity of the rollers 20b and 20d in rows B and D, which are subjected to large loads, is different from that of rollers 20b and 20d, which are subjected to small loads.
Row 20a between row and 0 row.

The rigidity is smaller than that of 20c.

Therefore, the load on rows B and D is the roller 20 of the rows.
b, decreased by flexural deformation of 20d, row B and D
The load distributed from the rows is transferred to the rollers 20a and 2 of rows A and 0.
Since 0c is shared and the load on the row increases, the load is distributed evenly to each row of rollers.

In addition to this embodiment, ceramic rollers with greater rigidity than the rope may be arranged in the roller rows to which small loads are applied, and steel rollers may be arranged in the roller rows to which large loads are applied. In this way, depending on the material of the rollers, the rigidity of the roller row to which a large load is applied can be made smaller than the rigidity of the roller row to which a small load is applied.

Figure 4 shows a fourth embodiment of the present invention, in which 208.20 g of tapered rollers with a small amount of crowning are arranged in the roller rows A and 0, which are subjected to small loads, and which are not subjected to large loads. The roller rows B and D have tapered rollers 20f with a large amount of crowning.

20h is installed.

In this way, by arranging tapered rollers with different crowning amounts in each roller row, the tapered rollers 20f, 2
The contact length of 0h is shorter than the contact length of the tapered rollers 20e and 20g with respect to the raceway surfaces of the roller rows A and 0, on which small loads are applied.

Therefore, the loads on rows B and D decrease, and the loads on rows A and 0 increase, so that the load distribution of each roller row functions in the direction of equalization.

In addition to this embodiment, the length of the rollers in the row of rollers to which a large load is applied may be shorter than the length of the rollers in the row of rollers to which a small load is applied. The number of rollers to be arranged may be a decimal number compared to the number of rollers in a row of rollers to which a small load is applied, and furthermore, the number of rollers to be arranged may be a decimal number than the number of rollers in a row of rollers to which a large load is applied. Rollers with smaller diameters may be provided, and in any of these cases, the load distribution of each roller row will function in the direction of equalization.

Note that the present invention is applicable not only to tapered roller bearing devices but also to other cylindrical roller bearing devices, needle roller bearing devices, and multi-row roller bearing devices consisting of combinations thereof.

[Effects of the Invention] As explained above, according to the present invention, the rigidity of the roller row to which a large load is applied in a multi-row roller bearing device is made smaller than the rigidity of the roller row to which a small load is applied. This function works in the direction of equalizing the load on each roller row, 1. There is no possibility that a larger load is applied to a particular roller row than on other roller rows, causing early damage, and the load on each roller row is reduced. The life time is averaged, the bearing life as a whole becomes longer, and a highly reliable multi-row roller bearing device can be obtained. Therefore, the multi-row roller bearing device of the present invention is a bearing device having the most suitable performance for the roll neck of a rolling mill.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing a first embodiment of the present invention, and a second embodiment of the present invention is shown in FIG.
The figure is a vertical sectional view showing a second embodiment of the invention, and FIG.
FIG. 4 is a vertical cross-sectional view showing a third embodiment of the present invention, FIG. 4 is a vertical cross-sectional view showing a fourth embodiment of the present invention, and FIG. 5 is a vertical cross-sectional view showing a conventional example of a bearing device for a roll neck of a rolling mill. Figure 6 is a load distribution diagram of each roller row of a roll neck bearing. Fig. 7 and Fig. 8 each show the load state during roll movement of the moving roll rolling mill, and Fig. 7 (al and Fig. 8 (a) are load center position diagrams, respectively, in Fig. 7). and FIG. 8(b) are load distribution diagrams for each roller row. In the figure, 10 is a roll, 11 is a roll neck, 11a, 1
1b is a groove in the roll neck, 13 is a 4-row tapered roller bearing, 14.15 is an inner ring, 14a and 15a are grooves in an inner ring, 1
6, 17, 18 are outer rings, 17a, 18a are grooves of the outer ring,
20a and 20c are solid rollers, 20b and 20d are hollow rollers, and 20e. 20g is 20f when the amount of crowning is small. 20h is the roller with a large amount of crowning, 22 is the bearing box,
22a and 22b are grooves in the bearing box. Patent Applicant NSK Ltd. Representative Patent Attorney Tetsuya Mori Patent Attorney Yoshiaki Naito Representative Patent Attorney Tadashi Shimizu Figure 5 Figure 2 Figure 7 (a) (b) Figure 8 ( a) (b) Two Ku I”

Claims (5)

[Claims] (1) Use where multiple rows of rollers are arranged on the raceway between the inner ring fitted on the rotating shaft and the outer ring held in the bearing box, and a load of a different size is applied to each roller row. In a multi-row roller bearing device under such conditions, at least one of the inner ring, outer ring, rotating shaft, and bearing box is an annular portion corresponding to each roller row, and corresponds to the roller row on which a large load is applied. The rigidity of the annular portion corresponding to the roller row to which a large load is applied, or the rigidity of the rollers of the roller row to which a small load is applied, is made smaller than the rigidity of the annular portion corresponding to the roller row to which a small load is applied, or the rigidity of the rollers of the roller row to which a small load is applied. , or at least one of the contact length, diameter, and number of rollers of the roller row to which a large load is applied to the raceway surface of the roller row to which a small load is applied than the contact length and diameter of the rollers to the raceway surface of the roller row to which a small load is applied. A multi-row roller bearing device characterized by a smaller number of rollers than the number of rollers. (2) At least one of the inner diameter surface of the inner ring, the outer diameter surface of the outer ring, the outer circumferential surface of the rotating shaft, and the inner circumferential surface of the bearing box has a circumferential The multi-row roller bearing device according to claim 1, wherein a concave groove is formed in a direction. (3) The multi-row roller bearing according to claim 1, wherein hollow rollers are arranged in the roller rows to which large loads are applied, and solid rollers are arranged in the roller rows to which small loads are applied. Device. (4) The multi-row roller according to claim 1, wherein steel rollers are arranged in the roller rows to which large loads are applied, and ceramic rollers are arranged in the roller rows to which small loads are applied. Bearing device. (5) According to claim 1, in which rollers with a large amount of crowning are arranged in the roller row to which a large load is applied, and rollers with a small amount of crowning are arranged in the roller row to which a small load is applied. multi-row roller bearing device.