JPH11148516A - Double row roller bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of creep at a fitting surface of an inner ring and a shaft by engaging a projecting part provided on a side of one inner ring with a recessed part provided in a side of the other inner ring. SOLUTION: In a double row angular ball bearing, a plurality of same rectangular recessed parts 4a are provided in a side of one inner ring 4 with intervals in the circumferential direction. A plurality of same rectangular projecting parts 4b are provided on a side of the other inner ring 4 with interval in the circumferential direction, and engaged with the recessed parts 4a in the side of one inner ring. When a large load in the radial direction is applied to one inner ring 4, the inner ring 4 to which the load is applied slides on a shaft 5 in the circumferential direction. However both inner rings 4 are engaged due to rugged parts of the side of the inner ring 4, and the relative rotation in the circumferential direction of both inner rings 4 to the shaft 5 is prevented, and both inner rings are integratedly rotated. As a result, generation of a creep causing a problem on the bearing performance can be suppressed, and the service life of the bearing can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rolling bearing,
More specifically, the present invention relates to an improvement of a double-row rolling bearing applicable to a rolling bearing for an automobile wheel and the like, and more particularly to an improvement of a double-row rolling bearing for preventing the occurrence of creep between an inner ring and a shaft.

[0002]

2. Description of the Related Art Conventionally, double row rolling bearings are often used for supporting automobile wheels. In this case, the rolling bearing for a vehicle wheel receives a large radial load because it receives the weight of the vehicle directly, although the rotation speed of the shaft is relatively slow.

In a double-row rolling bearing in which the inner rings are separated (separated inner ring), when a large load is applied to the bearing, if the same load is applied to both inner rings due to the degree of load applied to the two inner rings, etc. Not necessarily. For example, when the vehicle turns sharply, the double-row rolling bearing receives a larger radial load, axial load and moment load due to acceleration applied to the vehicle. As described above, when a load is applied to a bearing due to a sudden turning of a normal car, an axial load other than a radial load is also applied at the same time.
It is rare that the same magnitude of load is applied to both separated inner rings. That is, a large load is generally applied to one inner ring, and a small load is often applied to the other inner ring.

[0004] In this case, a force acts to slide the inner ring to which a large load is applied in the circumferential direction with respect to the shaft. Therefore, if the interference between the inner ring and the shaft is small and the fitting strength is weak, the inner ring to which one large load is applied slides on the shaft in the circumferential direction. If the slip continues, creep occurs between the inner ring to which a large load is applied and the shaft, that is, harmful slip in the circumferential direction of the inner ring with respect to the shaft. Thus, creep is 2
Often, it occurs first on one of the inner rings rather than on one of the inner rings at the same time. When this creep occurs, the inner ring inner surface is gradually worn, which may cause abnormal noise, seizure of the inner ring and the shaft, and shorten the life of the bearing.

For this reason, conventionally, the interference between the inner ring and the shaft has been sufficiently ensured to prevent the occurrence of creep. However, if this interference is too large, the circumferential tensile stress acting on the inner ring becomes excessive. The inner raceway receives a radially inward repetitive load from the rolling elements, which also generates a tensile stress. If the tensile stress based on the fitting becomes excessive, the durability of the inner race is impaired. Therefore, there was a limit in increasing the interference.

[0006]

SUMMARY OF THE INVENTION The present invention reduces the occurrence of creep on the mating surface between the inner race and the shaft by changing the shape of the side surface of the inner race without increasing the interference between the inner race and the shaft. The purpose is to prevent it.

[0007]

SUMMARY OF THE INVENTION The present invention relates to a double row rolling bearing having a double row rolling element between a double row outer ring and two inner rings. It is an object of the present invention to provide a double-row rolling bearing characterized in that convex portions provided on side surfaces of an inner ring mesh with each other.

In the conventional double-row rolling bearing, a larger load is applied to one of the two inner rings, so that one of the inner rings tends to slide in the circumferential direction first. However, in the double-row rolling bearing of the present invention, a concave portion formed on the side surface of the inner ring,
The convex portion on the side surface of the other inner ring is engaged. With this structure, even if one of the inner rings tries to slide in the circumferential direction with respect to the shaft, the other inner ring is prevented from slipping. As a result, the occurrence of creep can be delayed as compared with the related art, and the life of the bearing is prolonged.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a double-row angular contact ball bearing device for a vehicle wheel according to an embodiment of the present invention. FIG. 2 is a front view of the inner race of FIG. A double row angular contact ball bearing is mounted on a bearing mounting surface 5a on the outer diameter surface of a hollow shaft 5 having a flange portion by press fitting or the like. The bearing comprises two axially arranged inner races 4 and one (integral) double row outer race 1.
And two rows of balls 2 interposed between the inner ring 4 and the double row outer ring 1, and two retainers 3 for holding the balls 2. The balls 2 are respectively arranged on tracks formed on the inner race 4 and the double row outer race 1. In this embodiment, a ball is used as a rolling element. However, the present invention is not limited to a ball, and a roller may be used.

As shown in FIG. 2, one side (right side in FIG. 2)
A plurality of the same rectangular recesses 4a are circumferentially spaced on the side surface of the inner ring. On the side surface of the other (left side in FIG. 2) inner ring, a plurality of same convex portions 4b of the same rectangle are spaced apart in the circumferential direction, and mesh with the concave portions 4a on the side surface of one inner ring. Here, both the concave portion 4a and the convex portion 4b on the side surface of the inner ring are formed over the entire thickness of the inner ring 4. The bearing assembly is fitted and pressed into a housing (not shown) on the outer peripheral surface of the double row outer race 1.

Next, prevention of creep occurring between the shaft 5 and the inner race 4 will be described. When a large radial load is applied to one of the inner rings 4, the inner ring 4 to which the load is applied is applied.
Tends to slide on the shaft 5 in the circumferential direction. However, the two inner rings 4 are engaged with each other by the concave and convex portions on the side surfaces of the inner rings, so that both the inner rings 4 are prevented from rotating relative to the shaft 5 in the circumferential direction, and rotate integrally. That is,
As compared with the case where there is no uneven portion on the side surface of the inner ring, the slip of the inner ring is doubled, and the sliding in the circumferential direction is suppressed.

As a result, it is possible to suppress the occurrence of creep, which is a problem in bearing performance. In this way, by suppressing the sliding of one of the inner rings 4 in the circumferential direction, the occurrence of creep between the shaft 5 and the inner ring 4 is suppressed, and the life of the double row angular contact ball bearing is extended. It is. In addition, since the structure is a simple structure in which the uneven portion is provided on the side surface of the inner ring, there is no need to complicate the manufacturing process of the bearing.

In order to further prevent creep between the inner race 4 and the shaft 5, it is desirable that the contact area between the two inner races 4 and the shaft 5 is as large as possible. That is, the contact area of the inner ring 4 with the shaft 5 is increased, and by increasing this area, the fitting strength with the shaft 5 can be increased. At the same time, it is most effective to make the fit areas of the two inner rings 4 equal to each other to prevent the occurrence of creep. If the fitting area of the two inner races 4 is unbalanced, the fitting strength tends to be unbalanced. Therefore, when a large load is applied to any of the inner rings 4, the inner ring 4 to which the load is applied tends to slide in the circumferential direction.

The size of the uneven portion on the side surface of the inner ring is not particularly limited. However, it is desirable to have the same shape as shown in the present embodiment from the viewpoint of cost and assemblability. In order to increase the fitting area between the inner ring 4 and the shaft 5 as much as possible, the circumferential length of the bearing of the concave portion 4a on the side surface of one inner ring and the circumferential length of the bearing of the convex portion 4b on the side surface of the other inner ring. It is desirable that the bearings have the same height, and that both the concave and convex portions are equally disposed in the circumferential direction of the bearing.

The axial length of the concave portion 4a and the convex portion 4b on the side surface of the inner ring is such that the ball 2 does not pass through the joint portion of the concave portion 4a and the convex portion 4b on the side surface of the inner ring when rolling on the track. It is necessary to This is because if the ball passes through the joint portion, the ball becomes difficult to roll, and smooth rolling of the ball 2 cannot be secured.

In this embodiment, the side surface of the inner ring is provided with rectangular irregularities and is joined to them. However, the shape of the irregularities is not particularly limited to a rectangular shape.
Any of a triangular shape, a wedge shape, and the like may be used. In particular, it is preferable that the fitting areas of the two inner races 4 with the shaft 5 are equal, and the side surfaces of the two inner races are desirably symmetrical.

The joint between the concave portion 4a and the convex portion 4b on the side surface of the inner ring is not particularly limited, but it is also possible to use an adhesive or the like, and furthermore, an intermediate fit or a tight fit. Even so, the two inner rings 4 are preferable because they operate integrally.

In the above embodiment, application to a double-row angular contact ball bearing has been described. However, the present invention is not limited to this and can be similarly applied to a double-row tapered roller bearing. The operation of the double row tapered roller bearing is almost the same as that of the double row angular ball bearing of the above embodiment, except that the rolling elements are tapered rollers. Therefore, the present invention has the same problem that creep occurs, and therefore it is preferable to implement the present invention to solve the problem.

[0019]

As described above, according to the present invention, the inner ring can be slid in the circumferential direction by the large load applied to the inner ring without increasing the interference between the inner ring and the shaft. Thus, it is possible to prolong the life of the bearing by preventing the occurrence of creep between the rotating shaft and the inner ring.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a double-row angular contact ball bearing device for a vehicle wheel according to an embodiment of the present invention.

FIG. 2 is a front view of the inner race of FIG. 1 of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Double row outer ring 2 Rolling element (ball) 3 Cage 4 Inner ring 4a Depression 4b Convex part 5 axis

Claims (1)

[Claims] 1. A double-row rolling bearing having a double-row rolling element between a double-row outer ring and two inner rings, wherein a recess provided axially on a side face of one inner ring is provided on a side face of the other inner ring. A double-row rolling bearing characterized in that convex portions engage with each other.