JPH0217218A - Roll bearing - Google Patents

Abstract

PURPOSE:To reduce drag, of fluid such as lubricating oil, acting to rolling bodies for suppressing generation of heat on a bearing by making close to orbital surfaces of bearing rings of at least inner peripheral face and other peripheral face of pillar members between pockets, on a retainer. CONSTITUTION:A space enclosed with a retainer main body 1a, neighboring pillars 6 and a ring 1b is constructed as a pocket 2 nearly rectangular form in plan view. A projection stripe member 1c getting wider in width in peripheral direction on outer side in radius direction is formed integrally on outside in radius direction of the pillar member 6. On a bore of a retainer 1, that is set to a little larger than the outer diameter of an inner race 5 for making the retainer so as to provide little clearance between the inner peripheral face of the retainer 1 and the outer peripheral face of the inner race 5 to make little of protrusion of rollers 3 on inner side in radius direction.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a rolling bearing configured to suppress heat generation, particularly in a high-speed rotation range.

<Prior Art> For example, in a cylindrical roller bearing shown in FIGS. 6 and 7, rollers 3 as rolling elements rotatably housed in pockets 2 of a cage 1 are arranged on the outer peripheral surface of the cage 1. It is held in the retainer 1 in a state in which it protrudes more radially outward and more radially inward than the inner circumferential surface. This example shows a type in which the cage 1 is guided by the outer ring 4. It is set larger than the dimensions.

As explained above, the rollers 3 have conventionally protruded into and out of the cage l in the radial direction. Incidentally, the thickness of the cage 1 is generally set so that the area covered by the pillars 6 between the pockets 2 of the cage 1 over the rollers 3 is approximately 5094 times the area of the rollers 3 when viewed from the rolling direction. ing. This is Koro 3
This is based on the purpose of reducing contact resistance with the inner peripheral surface of the pocket 2 of the cage 1.

<Problems to be Solved by the Invention> By the way, when a rolling bearing is used in a high speed rotation range of 10,000 rpm or higher, for example, there is a cage in the space between the inner and outer rings. , fluid resistance of lubricating oil and the like against rotating objects including the rollers 3 becomes a problem.

Conventionally, turbine oil with low viscous resistance has been used as a lubricant for use in high-speed rotation ranges, but
If the rollers 3 protrude significantly from the cage 1 as in the conventional example shown in Figures 1 and 7, the drag force of fluid such as lubricating oil acting on the rollers 3 will increase, and as a result the heat generation of the entire bearing will increase. Therefore, the continuous use time at high speed rotation becomes shorter.

The present invention was made in view of the above circumstances, and an object of the present invention is to reduce the drag force of fluid such as lubricating oil acting on the rolling elements, and to suppress heat generation in the bearing.

<Means for Solving Problem i1> In order to achieve the above object, the present invention has the following configuration.

That is, the rolling bearing according to the present invention is characterized in that the inner circumferential surface and outer circumferential surface of at least the columnar portion between the pockets of the retainer are close to the raceway surface of the raceway ring.

Effect〉 The effects of the configuration of the present invention are as follows.

Since the rolling elements hardly protrude inward or outward in the radial direction from the cage when viewed from the rolling direction, the drag force of fluid such as lubricating oil acting on the rolling elements can be suppressed to a small level.

<Example> Hereinafter, an example of the present invention will be described in detail based on the drawings.

An embodiment of the present invention is shown in FIGS. 1 to 5.
In this embodiment, an example in which the present invention is applied to a cylindrical roller bearing will be described. In addition, in the figures, the same reference numerals as those in FIGS. 6 and 7 of the conventional example refer to the same parts, etc., as indicated by the reference numerals in this embodiment. Therefore,
In this embodiment, only the configurations that are different from the conventional example will be explained in detail, and the explanation of the common configurations will be omitted.

The cylindrical roller bearing of this embodiment has a different structure from the conventional example by making the cage l as thick as possible in the space between the inner and outer rings so that it covers almost the entire surface of the rollers 3 when viewed from the rolling direction. It is that you are.

As shown in FIG. 3, the cage l has an assembly structure, and is integrated with a rivet or the like after the rollers 3 are housed. Specifically, the cage l includes a cage main body 1a having a plurality of pillars 6 protruding in the axial direction, for example, in a comb-like shape, and a ring fixed to the end surface of each pillar 6 with a rivet 7. 1b
The space surrounded by the cage main body 1ah, the adjacent column part 6 and the ring ]b is a pocket 2 which is approximately rectangular in plan view.
It is configured as. A protrusion 1c is integrally formed on the radially outer side of the column 6, and the protrusion 1c becomes wider in the circumferential direction on the outer diameter side. It is arranged to cover the outer diameter side in the radial direction of No. 3.

The inner diameter of the cage 1 is also set to be slightly larger than the outer diameter of the inner ring 5, so that there is only a small gap between the inner circumferential surface of the cage 1 and the outer circumferential surface of the inner ring 5. The protrusion on the inner diameter side is reduced.

The outer ring 4 is also divided into two parts so that the cage 1 having the unique shape of this embodiment described above can be incorporated therein. The outer ring 4 consists of an outer ring main body 4b having a radially inward flange 4a at one axial end, and a collar ring 4c having a roughly LJ-shaped cross section attached to the other axial end of the outer ring main body 4b. It is configured such that it is integrated after incorporating the retainer 1 containing the retainer 3.

Next, the results of a simulation of a cylindrical roller bearing conducted by the present proponents are shown in the graph of FIG. In the graph in the figure, the horizontal axis represents the ratio of the area covering the rollers 3, and the vertical axis represents the amount of heat generated.

The model number of the cylindrical roller bearing used in this experiment is NU2228.
The experimental conditions were a radial load of 1000 kgf,
The rotation speed is set to 500 rpm, and the lubricating oil is set to turbine oil.

Then, the ratio RA of the area covering the rollers 3 is determined by the following equation.

In Fig. 5, the area of the part where the rollers 3 are hidden by the cage 1 is A3, the area of the part where the rollers 3 protrude to the radially outer side of the cage L is A2, and the area of the rollers 3 is on the radially inner side of the cage. The area of the protruding part is A.

shall be.

R^ = X100 (%
)AI +At +A.

In the graph of FIG. 4, it can be seen that the amount of heat generated by the entire bearing, indicated by a, decreases as the area ratio RA covering the rollers 3 increases. Now, the amount of heat generated at the contact area between the rollers and the outer ring raceway shown as b, the amount of heat generated in the cage pocket shown as C, the amount of heat generated at the contact area between the rollers and the inner ring raceway shown as d, and the cage guide surface shown as e ( The amount of heat generated on the roller 3 (outer circumferential surface) remains almost constant regardless of the increase or decrease in the ratio RA of the area covering the roller 3; The amount of heat generated by the drag force is the area ratio RA covering the roller 3.
It can be seen that as the value increases, the value decreases. In other words, it can be seen that the area ratio RA covering the rollers 3 influences the amount of heat generated by the entire bearing.

Through experiments in the above-mentioned medium-speed rotation range, we confirmed that increasing the area ratio R1 covering the rollers 3 can suppress the heat generation of the entire bearing. It can be assumed that heat generation can be suppressed more effectively by applying the present invention in the above range.

Based on the above results, the ratio RA of the area covered by the column parts 4 of the cage 1 over the rollers 3 is set to about 80 as the range where the heat generation is small.
I think it is desirable to set it to % or more.

In addition, although the above-mentioned embodiment is explained using an example applied to a cylindrical roller bearing, it goes without saying that the present invention is not limited thereto, and can also be applied to various types of roller bearings and ball bearings.

<Effects of the Invention> As explained above, according to the present invention, since the rolling elements are hardly protruded in or out of the cage in the radial direction when viewed from the rolling direction, the amount of fluid such as lubricating oil acting on the rolling elements is reduced. Drag can be kept small. Therefore, especially when the bearing is used in a high-speed rotation range, the heat generation of the entire bearing can be suppressed, and the continuous use time can be extended.

[Brief explanation of the drawing]

1 to 5 relate to one embodiment of the present invention;
The figure is a vertical cross-sectional side view of the upper half of the cylindrical roller bearing, and Figure 2 is the first half of the cylindrical roller bearing.
Figure 3 is an exploded perspective view showing a part of the cage, Figure 4 is a graph showing the experimental results by Nyumireshin, Figure 5 explains the elements for calculating the roller coverage ratio. FIG. Furthermore, FIGS. 6 and 7 show the conventional example, and FIG. 6 is a vertical sectional side view corresponding to FIG. 1, and FIG.
FIG. 1...Cage, 2...Pocket, 3...Roller,
6...Column part. Figure 1

Claims (1)

[Claims] (1) A rolling bearing characterized in that the inner circumferential surface and outer circumferential surface of at least the column portion between the pockets of the retainer are close to the raceway surface of the bearing ring.