JP2001020949A - Bearing device for drive shaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent entry of foreign matter into the inside of a bearing and prevent influence on a closed member due to variation of internal pressure of the bearing. SOLUTION: A bearing device for a drive shaft to support the drive shaft on one end of a shaft part of which a pinion is provided and on the other end side of which the drive shaft is spline fitted on a housing free to revolve has an outer ring 60 supported and fixed to the housing 5, inner rings 62, 63 to be fitted on a pinion shaft 1, a plural number of tapered rollers 64 to be arranged between the inner and outer rings, a first closed member 7 arranged between the inner and outer rings 63, 60 on the side of the pinion 2, a second closed member 8 arranged between the housing 5 and the drive shaft 3 and a breather hole 10 provided in the housing 5 and to communicate an inside space of the housing 5 between the first and second sealing members 7, 8 and an outer space of the housing 5 to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a drive shaft bearing device for transmitting power to a differential device such as an automobile.

[0002]

2. Description of the Related Art Conventionally, as this type of drive shaft bearing device, one disclosed in Japanese Utility Model Laid-Open No. 5-96551 is known. In this device, a pinion is provided at one end of a shaft portion, and a drive shaft to which a drive shaft is spline-fitted at the other end side is rotatably supported by a housing. A double-row tapered roller bearing including an inner ring to be fitted and a plurality of tapered rollers disposed between the inner and outer rings is disposed. Then, the inside of the bearing on the pinion side is opened, and a sealing member is arranged between the housing on the anti-pinion side and the drive shaft.

[0003]

In the above-mentioned prior art, the pinion and the ring gear (not shown) meshing with the pinion and the inside of the bearing are lubricated with the same lubricating oil. It may penetrate inside and cause a reduction in bearing life.

In order to solve this problem, Japanese Patent Laid-Open Publication No.
Japanese Patent Application Laid-Open No. 5449 proposes a drive shaft bearing device in which sealing members for sealing between the inner and outer rings at both ends of the outer ring of the double row tapered roller bearing are provided. However, in this conventional device, since the inside of the bearing is completely sealed, entry of foreign matter such as gear abrasion powder into the inside of the bearing as in the above-described conventional device is prevented. Due to an increase in the internal pressure inside the bearing, the sealing property of the sealing member may be reduced and lubricating oil may leak, which may easily lead to insufficient lubrication of the bearing. Furthermore, when the rotation of the bearing is stopped, the internal pressure inside the bearing decreases, and if the lip sticking phenomenon of the sealing member occurs, the bearing torque increases and abnormal lip wear may occur.

[0005] The present invention has been made to address the above-described problems, and has been made to prevent foreign matter from entering the inside of a bearing,
It is an object of the present invention to provide a drive shaft bearing device that prevents a change in bearing internal pressure from affecting a sealing member.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a drive shaft in which a pinion is provided at one end of a shaft portion and a drive shaft is spline-fitted to the other end. A drive shaft bearing device rotatably supported by a housing, comprising: an outer ring supported and fixed to a housing; an inner ring fitted to a pinion shaft; a plurality of tapered rollers disposed between the inner and outer rings; A first sealing member disposed between the inner and outer rings, a second sealing member disposed between the housing and the drive shaft, and a housing inner space and a housing outer space provided between the first and second sealing members. And a breather hole that communicates with

[0007]

1 to 3 show one embodiment of the present invention. A pinion 2 meshing with a ring gear of a differential device (not shown) is provided at one end of a shaft portion 1 and a drive is provided at the other end side. A drive shaft D on which the shaft 3 is spline-fitted 4 is rotatably supported by a bearing 6 in an aluminum housing 5. This bearing 6
Is a double row tapered roller bearing, and has an integral outer race 60 having a pair of tapered raceway surfaces 60a, 60b whose inner diameter increases from the central portion toward both ends in the axial direction. A pair of inner races 62, 63 having opposed raceway surfaces 62a, 63a and having small end surfaces abutted and integrated by a retaining ring 65, and between raceway surfaces 60a, 62a between the inner and outer rings 60, 62, 63; A plurality of tapered rollers 64, 64 are disposed between the raceway surfaces 60b, 63a. The outer race 60 is fitted to the housing 5 and a radial outward flange 61 formed at one end of the outer race 60 is bolted to the housing. 5 and the inner rings 62 and 63 are
And is pinched and fixed between the end face of the pinion 2 and the end face of the drive shaft 3.

A dustproof cover 9 partially covering the outer peripheral surface of the housing 5 is fixed to the outer peripheral surface of the drive shaft 3, and a first sealing member 7 is arranged between the inner and outer rings 63 and 60 on the pinion 2 side. A second sealing member 8 is disposed between the housing 5 and the drive shaft 3. As shown in detail in FIG. 2, the first sealing member 7 has cylindrical portions 71a, 72a and radial flanges 71 respectively on inner and outer rings 63, 60, respectively.
b, 72b L-shaped metal rings 71, 7 so that they face each other
2 are fitted and fixed, and a plurality of lips 74 of an elastic body 73 such as rubber molded integrally with the metal ring 71 on the outer ring 60 side are connected to the inner ring 6.
This is a configuration in which the metal ring 72 on the third side is slidably contacted. Further, as shown in detail in FIG. 3, the second sealing member 8 is fixed to the housing 5, and a main lip 80 and an auxiliary lip 81 formed on the inner periphery are slid on the drive shaft 3, and The auxiliary lip 82 formed on the dustproof cover 9 is in sliding contact with the dustproof cover 9.

Further, the housing 5 is formed with a breather hole 10 for communicating the internal space of the housing 5 between the first and second sealing members 7 and 8 and the external space of the housing 5 so that the bearing 5 can rotate when the bearing rotates and when the bearing stops. Fluctuations in the bearing internal pressure are relieved, the bearing internal pressure is always made substantially the same as the external pressure, and the influence on the sealing members 7, 8 is minimized.

[0010]

According to the present invention, since the bearing portion is completely sealed, foreign matters can be prevented from entering the inside of the bearing, and the breather hole formed in the housing eliminates fluctuations in the bearing internal pressure when the bearing rotates and when the bearing stops after rotation. By doing so, it is possible to prevent the lubricant from leaking from the sealing member, the lip abrasion due to the lip sticking of the sealing member, and the increase in rotational torque.

[Brief description of the drawings]

FIG. 1 is a half sectional view of an embodiment of the present invention.

FIG. 2 is a sectional view of a first sealing member of FIG. 1;

FIG. 3 is a sectional view of a second sealing member of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pinion shaft 2 Pinion 3 Drive shaft 4 Spline fitting 5 Housing 6 Double row tapered roller bearing 7 1st sealing member 8 2nd sealing member 9 Dustproof cover 10 Breather hole 60 Outer ring 62 Inner ring 63 Inner ring D Drive shaft

Claims (1)

[Claims] 1. A drive shaft bearing device in which a pinion is provided at one end of a shaft portion and a drive shaft to which a drive shaft is spline-fitted at the other end side is rotatably supported by a housing. Outer ring, an inner ring fitted to the pinion shaft, a plurality of tapered rollers disposed between the inner and outer rings, a first sealing member disposed between the inner and outer rings on the pinion side, and between the housing and the drive shaft. A bearing device for a drive shaft, comprising: a second sealing member to be disposed; and a breather hole provided in the housing and communicating a housing internal space and a housing external space between the first and second sealing members.