JPH10252747A - Cylindrical roller bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure smooth rolling and improve durability by setting the member of rollers so that a basic static rated road is made a specific value against a radial load, and providing through holes in the radial direction on the column section between adjacent pockets in the peripheral direction of a retainer. SOLUTION: The number of cylindrical rollers 3 is set so that the basic static rated load Cor' of a bearing is made P<0.04 Cor' against the radial load P. Since this bearing has fewer rollers 3 than the standard bearing, the number of pockets 4a of a retainer 4 is fewer then that of the standard retainer, and column sections 4c are made wide in width. A roller drop stop 4e preventing the drop of the roller 3 is provided at the inner diameter side portion of each column section 4c, and a through hole 4f is provided on the column section 4c to reduce the weight of the retainer 4, accelerate the flow of a lubricant, and secure the elasticity of the column section 4c required for its incorporation into the pocket 4a of the roller 3. The smooth rolling of the retainer rollers 3 is secured even under a light radial load, and the life of the bearing can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical roller bearing used under such a condition that the acting radial load is smaller than the load capacity of a standard bearing.

[0002]

The cylindrical roller bearing has a large radial load-bearing capacity due to linear contact between the cylindrical roller and the raceway surface, and has a high speed because the rollers are guided by the inner ring or outer ring flange. Also suitable for rotation.

However, there are cases where the operation is performed under the condition that the radial load is smaller than the standard load capacity due to the relationship with the counterpart device or the like to be incorporated. In this case, depending on the magnitude of the acting radial load, The rollers do not roll smoothly (slip occurs), and an appropriate bearing function may not be secured. Generally, the radial load P acting on the bearing is
It is said that, when the basic static load rating of the bearing is 4% or less, a phenomenon that smooth rolling of the rollers is prevented may occur. In particular, in the case of a large-sized (bearing inner diameter of 300φ or more) thin bearing, the number of rollers increases, so this tendency is strong. In addition, the radial internal clearance (initial clearance) is set to be larger than the normal clearance according to the use conditions. If so, the tendency is stronger.

An object of the present invention is to ensure smooth rolling of a cylindrical roller under a light radial load, thereby ensuring an appropriate bearing function and at the same time improving the durability of a bearing.

[0005]

SUMMARY OF THE INVENTION The present invention is directed to a cylindrical roller bearing used under a condition that an applied radial load P is 4% or less of a basic static load rating Cor of a standard bearing.

A cylindrical roller bearing according to the present invention includes an inner ring, an outer ring, a plurality of cylindrical rollers interposed between the inner ring and the outer ring, and a cage formed by shaving and having a plurality of pockets for holding the cylindrical rollers. ing. Then, the basic static load rating Cor 'of the bearing is such that P> 0.
The number of cylindrical rollers is set to be 04Cor ',
In addition, the retainer has a through-hole penetrating in a radial direction in a pillar portion between pockets adjacent in the circumferential direction of the retainer.

Here, the "basic static load rating" generally causes a total permanent deformation of 0.0001 times the rolling element diameter at the center of the contact portion between the raceway surface receiving the maximum stress and the rolling element. Refers to static load. Basic static load rating of standard bearing Cor
Are displayed in the product catalog for each bearing type and bearing size.

The basic static load rating is proportional to the number of rolling elements, and decreases as the number of rolling elements decreases. Taking advantage of this, the number of cylindrical rollers is set so as to satisfy the load condition under which smooth rolling of the cylindrical rollers is ensured. Specifically, the number of cylindrical rollers is made smaller than that of the standard bearing so that the radial load P acting and the basic static load rating of the bearing are Cor ', and P>0.04Cor'. As a result, an appropriate radial load is applied to each cylindrical roller, and smooth rolling of the cylindrical rollers is ensured.

On the other hand, if the number of cylindrical rollers is reduced, the circumferential dimension of the pillar portion of the retainer increases (because the number of pockets decreases), which leads to an increase in the weight of the retainer. In the roller guide (type in which the cage is guided by cylindrical rollers), an increase in the weight of the cage causes an increase in bearing noise due to an increase in whirling inertia of the cage. In this case, lubrication shortage is likely to occur due to an increase in the surface pressure of the cage guide. In addition, in cages formed by shaving (milled cages), roller stoppers are usually provided on the inner diameter side or outer diameter side portion of the column, and during assembly, the roller rollers are elastically deformed and the cylindrical roller is deformed. However, if the rigidity of the column is too high and the rigidity thereof is too high, there is a problem that the work of assembling the cylindrical roller becomes difficult.

[0010] In the present invention, the reason why the through hole is formed in the pillar portion of the cage in the radial direction is to eliminate the above-mentioned adverse effects caused by reducing the number of cylindrical rollers. That is, by forming a through hole in the pillar portion of the cage, the weight of the cage is reduced, the flow of the lubricant inside the bearing is promoted, and the elasticity of the pillar portion necessary for incorporating the cylindrical roller is ensured. Therefore, the above-mentioned adverse effects are eliminated.

[0011]

Embodiments of the present invention will be described below.

The cylindrical roller bearing shown in FIG. 1 is a large-sized cylindrical roller bearing having a nominal bearing inner diameter of 300 φ (mm) or more, and includes an inner ring 1, an outer ring 2, and a plurality of cylindrical rollers 3 interposed between the inner ring 1 and the outer ring 2. And a retainer (cut-out retainer) 4 formed by shaving to retain the cylindrical roller 3. In this embodiment, the inner race 1 has flanges 1b on both sides of the raceway surface 1a.
The end face of the cylindrical roller 3 is contact-guided by the flange face b, and the inner diameter face of the retainer 4 is contact-guided by the outer diameter face of the flange 1b. The outer ring 2 has only the raceway surface 2a and does not have a flange. The lubrication system is not particularly limited, but is preferably oil lubrication.

The cylindrical roller bearing of this embodiment is used under the condition that the radial load P is 4% or less (P ≦ 0.04 Cor) of the basic static load rating Cor of a standard cylindrical roller bearing of the same type and size. . The radial internal clearance (initial clearance) is set to be larger than the normal clearance. Then, in order to ensure smooth rolling of the cylindrical roller 3 under such use conditions (light radial load), the basic static rated load Cor 'of the bearing is P>0.04Cor' with respect to the radial load P. The number (Z) of cylindrical rollers is set so that

For example, in the case of a standard cylindrical roller bearing having a bearing inner diameter of 500 φ, the basic static load rating Cor is 292,000 kg.
f (value described in product catalog), normal clearance is 180 to 3
The standard number (Z) of 20 μm cylindrical rollers is 27.
In this case, P ≦ 0.04Cor = 11680 kgf. The appropriate number of cylindrical rollers (Z ') varies depending on the magnitude of the radial load P. Assuming that P = 10000 kgf, P = 10000>0.04Cor',
Cor '<250,000, and since the basic static load rating is proportional to the number of cylindrical rollers, Z'<27 × (250,000 / 292000) = 23.
1 (book). Therefore, in this case, by setting the number (Z ') of the cylindrical rollers 3 to 23 or less, it is possible to apply an appropriate radial load to each cylindrical roller 3 and to ensure smooth rolling thereof. it can.

As shown in FIG. 2 in an enlarged manner, the retainer 4
A plurality of pockets 4a for accommodating and holding the cylindrical roller 3 are provided at equal circumferential positions, and an annular portion 4b in which both sides in the axial direction of the pocket 4a are guided by the inner ring 1 and a pocket 4a adjacent in the circumferential direction are provided. It is an annular body that has become a wide pillar portion 4c. As described above, in the cylindrical roller bearing of this embodiment, the number of the cylindrical rollers 3 is smaller than that of the standard bearing. Therefore, the number of pockets 4a of the retainer 4 is smaller than that of the standard retainer. , The column portion 4c is wide.

A roller stopper 4e for preventing the cylindrical roller 3 from falling off is provided on the inner diameter side portion of the column 4c. When accommodating the cylindrical roller 3 in the pocket 4a,
Press the cylindrical roller 3 against the roller stopper 4e from the inner diameter side,
The cylindrical roller 3 is pushed into the pocket 4a while elastically expanding the roller stopper 4e in the circumferential direction.

Further, each of the pillars 4c reduces the weight of the retainer 4, promotes the flow of the lubricant inside the bearing, and forms the pillars 4c necessary for incorporation into the pockets 4a of the cylindrical rollers 3. Through hole 4f to ensure elasticity
Is provided. Each through-hole 4f is formed by radially punching a center portion of each pillar 4c in the circumferential direction. The through hole 4f in this embodiment has a long hole shape, and has an axial width approximately equal to that of the pocket 4a and a circumferential width approximately 1/3 that of the column portion 4c. Both ends in the axial direction of the through hole 4f are circular arcs, in order to reduce stress concentration. The shape, size, and number of the through holes may be appropriately determined as long as the above functions can be ensured, and are not particularly limited to the above examples. For example, a polygonal shape such as a circle, a rectangle, and a hexagon can be adopted as the shape of the through hole.

Since the weight of the retainer 4 is reduced by an amount corresponding to the volume of the through hole 4f, the contact surface pressure at the contact portion (guide portion) between the retainer 4 and the inner ring 1 is reduced, so that the guide portion is worn. It leads to reduction. In addition, since the lubricating oil inside the bearing can flow to the inner diameter side or the outer diameter side through the through hole 4f, lubrication conditions in the raceway surfaces 1a, 2a and the guide portion of the retainer 4 are advantageous. Furthermore, the through hole 4f
By forming, the column portion 4c is given an appropriate elasticity, so that the operation when the cylindrical roller 3 is incorporated into the pocket 4a is also facilitated.

[0019]

As described above, according to the present invention, the number of cylindrical rollers is set so that the basic static load rating Cor 'of the bearing is such that P>0.04Cor' with respect to the radial load P. Even under a light radial load, smooth rolling of the cylindrical rollers is ensured, and an appropriate bearing function is exhibited. Thereby, the life of the bearing can be increased. At the same time, the through hole formed in the column of the cage reduces the weight of the cage, promotes the flow of lubricant inside the bearing, and ensures the elasticity of the column required for incorporating the cylindrical roller. Increase in bearing noise due to adoption of the above means,
It is possible to solve the problems of increasing the surface pressure of the cage guide, insufficient lubrication, and incorporation of the cylindrical rollers.

[Brief description of the drawings]

FIG. 1 is a sectional view of a large-sized cylindrical roller bearing according to an embodiment.

FIG. 2 is a partial plan view (FIG. A) and a partial cross-sectional view (FIG. B) of the cage.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inner ring 2 Outer ring 3 Cylindrical roller 4 Cage 4a Pocket 4c Column part 4f Through hole

Claims (1)

[Claims] 1. A cylindrical roller bearing used under a condition that an applied radial load P is 4% or less of a basic static load rating Cor of a standard bearing, wherein an intermediate ring is provided between an inner ring, an outer ring, and an inner ring and an outer ring. A plurality of cylindrical rollers and a cage by shaving having a plurality of pockets for holding the cylindrical rollers, wherein the basic static load rating Cor 'of the bearing is P>0.04Cor' with respect to the radial load P. A cylindrical roller bearing, wherein the number of cylindrical rollers is set so as to form a cylindrical roller bearing, and a through-hole penetrating in a radial direction is provided in a pillar portion between pockets adjacent in a circumferential direction of the retainer.