JP2002250348A - Thrust cylindrical roller bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thrust cylindrical roller bearing capable of suppressing the action of a centrifugal force generated by revolution of a cylindrical roller on a cage. SOLUTION: This bearing is constituted by arranging a plurality of cylindrical rollers 3 held in the cage 4 between a pair of opposing bearing rings 1 and 2. Cross sectional shapes of raceway track faces 1a, 2a of both bearing rings 1, 2 are such shapes that the centrifugal force generated by the revolution of the roller 3 is supported by the raceway track faces 1a, 2a. For example, shapes of the raceway track faces 1a, 2a are tapered shapes in which intervals between the raceway track faces are spreaded on an inside diameter side, or curved surface shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thrust cylindrical roller bearing used for various devices, for example, car air conditioners and industrial machinery in general, and more particularly, to a thrust thrust capable of suppressing a centrifugal force caused by a revolution of a roller from acting on a cage. It relates to a cylindrical roller bearing.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 8, in a thrust cylindrical roller bearing, a raceway surface 10
1a and 102a generally have a planar shape. The cylindrical roller 103 can revolve without being protruded outside by centrifugal force by being guided by the retainer 104.

[0003]

However, in the conventional flat raceway surfaces 101a and 102a, since the retainer 104 is strongly subjected to the centrifugal force of the cylindrical roller 103, the following problems may occur. is there. (A) When the end face of the cylindrical roller 103 slides on the retainer 104, a pocket of the retainer 104 is worn and a drilling phenomenon in which a hole is formed occurs. (B) When the cylindrical roller 103 and the retainer 104 strongly interfere with each other, an increase in bearing torque and an uneven bearing torque occur. (C) Strong interference between the cylindrical roller 103 and the retainer 104 causes an increase in sound and excessive heat generation.

An object of the present invention is to provide a thrust cylindrical roller bearing capable of suppressing the centrifugal force of a cylindrical roller from acting on a cage.

[0005]

A thrust cylindrical roller bearing according to the present invention is directed to a cylindrical roller bearing having a plurality of cylindrical rollers held by a retainer between a pair of facing races. The shape of the raceway surface of one or both races is a cross-sectional shape in which the centrifugal force generated by the revolution of the rollers is supported by the raceway surface. In this way, by allowing the centrifugal force generated by the revolution of the rollers to be supported on the raceway surface, the centrifugal force caused by the revolution of the cylindrical rollers acts on the cage during bearing rotation, or does not act at all. Can be.

In the present invention, the shape of the raceway surface is, specifically, a shape in which the interval between the raceway surfaces gradually increases toward the inner diameter side in the radial direction of the raceway ring. The gradually expanding shape may be a tapered shape or a curved shape. In the case of a curved surface shape, for example, the shape is such that the track surface side is concave. It is preferable that both races have a raceway surface that gradually widens toward the inner diameter side, but any one of the races may be used. When only one of the races has the above-described raceway surface shape, the raceway surface of the other raceway has a planar shape. When the raceway surface has a tapered shape spreading toward the inner diameter side in the radial direction of the raceway as in this configuration, centrifugal force generated in the cylindrical roller by the revolution of the cylindrical roller is supported by the raceway surface of the raceway ring. For this reason, the centrifugal force of the cylindrical roller is suppressed from acting on the cage, or the centrifugal force does not act on the cage at all. In this way, the fact that the centrifugal force of the cylindrical roller acts on the cage is reduced or eliminated,
The following actions are obtained.・ Prevents the drilling phenomenon of the cage.・ Reduced bearing torque.・ Improved bearing torque unevenness.・ Improvement of poor sound.・ Reduced heat generation at the interference part between the cylindrical roller and the cage.

In each of the above configurations of the present invention, the outer peripheral surface of the cylindrical roller may have a crowning shape.
By adopting the crowning shape as described above, edge load of the cylindrical roller is prevented from being generated on the raceway surface and the cylindrical roller. By making the raceway surface of the raceway into a tapered shape or a curved surface shape in which the inner diameter side is widened, edge load of the cylindrical roller is more likely to occur on the outer diameter side of the raceway than in the case of a flat surface. Edge loading is prevented.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, this thrust cylindrical roller bearing has a plurality of cylindrical rollers 3 held by a retainer 4 between a pair of facing races 1 and 2. One of the bearing rings 1 and 2 is a fixed wheel, and the other bearing ring 1 and 2 is a rotating wheel. The raceways 1a, 2a of the races 1, 2 have a tapered shape in which the interval G between the raceways 1a, 2a gradually increases toward the inner diameter side in the raceway radial direction. For this reason, the bearing rings 1 and 2 are
As shown in the figure, the outer diameter side has a tapered cross-sectional shape in which the thickness gradually increases. The taper angle α of the raceway surfaces 1a and 2a is a minute angle, for example, about 0.002 rad.

As shown in the sectional view and the partially cutaway plan view of FIGS. 3A and 3B, the retainer 4 is arranged in the circumferential direction of the ring-shaped flat plate and has a plurality of pockets 4a for holding the cylindrical roller 3.
Is provided. The retainer 4 is made of, for example, aluminum, and the pocket 4a is drilled by wire cutting or the like. As shown in FIG. 4A, the cylindrical roller 3 has an outer peripheral surface in a crowning shape. The portion having the crowning shape is only a portion of a part of the length range L at the end of the cylindrical roller 3, and the outer peripheral surface of the cylindrical roller at the remaining central portion is a cylindrical surface. The crowned portion is preferably provided at both ends of the cylindrical roller 3 so as not to be affected by a mistake in assembling the cylindrical roller 3. However, only a portion corresponding to the outer diameter side of the bearing rings 1 and 2 is provided. Is also good. In addition, as the cylindrical roller 3, in addition to the above, as shown in FIG. 5A, the outer peripheral surface is formed into a cylindrical surface over the entire length and chamfered at both ends, or as shown in FIG. The outer end surface may have a convex spherical shape.

According to the thrust cylindrical bearing of this configuration, the raceway surfaces 1a and 2a are tapered so as to expand toward the inner diameter side in the radial direction of the raceway ring. Track surface 1 of bearing rings 1 and 2
a, 2a. Therefore, the centrifugal force of the cylindrical roller 3 is suppressed from acting on the cage 4, or the centrifugal force does not act on the cage 4 at all. Therefore, the cage 4
Drilling phenomenon is prevented, bearing torque is reduced,
Uneven bearing torque and poor acoustics have been improved.
And the heat generated by the interference part of the cage 4 is reduced. In addition, since the outer peripheral shape of the cylindrical roller 3 is a crowning shape,
Although the raceway surfaces 1a and 2a have a tapered shape in which the inner diameter side is widened, the edge load of the cylindrical roller 3 is prevented from being generated on the raceway surfaces 1a and 2a and the cylindrical roller 3.

FIG. 6 shows verification data comparing the bearing torque with respect to each rotation speed for the thrust cylindrical roller bearing of this embodiment and the conventional example shown in FIG. As is clear from the figure, in the thrust cylindrical roller bearing of this embodiment, the bearing torque is reduced at any rotation speed as compared with the conventional example.

FIG. 7 shows another embodiment of the present invention.
The thrust cylindrical roller bearing of this embodiment is different from the above embodiment (FIG. 1) in that the raceway surfaces 1a, 2a of the two races 1, 2 are provided.
Is a curved surface shape in which the distance between the raceway surfaces 1a and 2a gradually increases toward the inner diameter side in the radial direction of the raceway ring. The curved shape is a shape in which the raceway surfaces 1a and 2a are concave. The outer peripheral shape of the cylindrical roller 3 is a crowning shape. Other configurations are the same as those in the above embodiment.

Even when the raceway surfaces 1a and 2a are curved as described above, the revolving centrifugal force of the cylindrical roller 3 is applied to both raceways 1 and 2.
And the centrifugal force of the cylindrical roller 3 acting on the retainer 4 is suppressed. Also in this case, the outer peripheral shape of the cylindrical roller 3 is formed into a crowning shape, thereby preventing edge load.

[0014]

According to the thrust cylindrical roller bearing of the present invention, the raceway surface of the bearing ring has a cross-sectional shape in which the centrifugal force generated by the revolution of the rollers is supported by the raceway surface. Is suppressed or no effect at all. Therefore, effects such as prevention of the drilling phenomenon of the cage, reduction of the bearing torque, improvement of the bearing torque unevenness and acoustic failure, and reduction of heat generation at the interference portion between the cylindrical roller and the cage are obtained. When the raceway surface is formed into a tapered shape or a curved shape in which the inner diameter side of the raceway extends, the centrifugal force generated in the cylindrical roller by the revolution of the cylindrical roller can be favorably supported by the raceway surface. Also,
When the outer peripheral surface of the cylindrical roller is formed into a crowning shape, the edge load of the cylindrical roller is prevented from acting even if the raceway surface is formed into a tapered shape or a curved shape that spreads toward the inner diameter side as described above.

[Brief description of the drawings]

FIG. 1 is a sectional view of a thrust cylindrical roller bearing according to an embodiment of the present invention.

FIG. 2 is a sectional view of a bearing ring in the bearing.

FIG. 3A is a sectional view of a cage in the bearing,
(B) is a fragmentary plan view of the retainer.

FIG. 4A is a front view of a cylindrical roller in the bearing,
(B) is an enlarged view of a portion M in (A).

FIG. 5 is a front view showing other examples of the cylindrical roller used in the bearing.

FIG. 6 is an explanatory diagram showing a result of comparing a bearing torque of the bearing with a conventional example.

FIG. 7 is a sectional view of a thrust cylindrical roller bearing according to another embodiment of the present invention.

FIG. 8 is a sectional view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Outer ring 2 ... Inner ring 1a, 2a ... Raceway surface 3 ... Cylindrical roller 4 ... Cage G ... Spacing

Claims (6)

[Claims] In a cylindrical roller bearing having a plurality of cylindrical rollers held by a retainer between a pair of facing races, the shape of the raceway surface of one or both races is determined. A thrust cylindrical roller bearing having a cross-sectional shape in which centrifugal force generated by the revolution of a roller is supported on a raceway surface. 2. A cylindrical roller bearing having a plurality of cylindrical rollers held by a retainer between a pair of facing races, wherein one or both races have a raceway surface shape of: A thrust cylindrical roller bearing having a tapered shape in which an interval between raceway surfaces is widened toward an inner diameter side in a raceway radial direction. 3. A cylindrical roller bearing in which a plurality of cylindrical rollers held by a retainer are arranged between a pair of facing races, wherein one or both races have a raceway surface shape of: A thrust cylindrical roller bearing having a curved surface shape in which an interval between raceway surfaces is widened toward an inner diameter side in a raceway radial direction. 4. The thrust cylindrical roller bearing according to claim 3, wherein the curved surface has a shape in which a raceway surface side is concave. 5. The thrust cylindrical roller bearing according to claim 2, wherein the shape of the two bearing rings is such that the space between the raceways is widened toward the inner diameter side in the radial direction of the bearing rings. 6. The thrust cylindrical bearing according to claim 1, wherein an outer peripheral surface of the cylindrical roller has a crowning shape.