JP2001246903A - Hub unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide structure of a hub unit capable of reducing or restraining transmission of vibration from a constant velocity joint to a double row rolling bearing to improve the life of the bearing. SOLUTION: In this hub unit 1, the constant velocity joint 5 is incorporated in the inner periphery of the double row rolling bearing 3, a flange 17 directing outward in the radial direction is formed on the outer end in the axial direction of one inner ring 7 of the double row rolling bearing, and with a disc rotor 19 of a disc brake device and a wheel applied to the outer surface of the flange, the hub unit is installed. In this hub unit, an elastic member 39 is interposed between a set of inner rings 7, 8 of the double row rolling bearing and an outer ring of the constant velocity joint, whereby the vibration of the constant velocity joint is damped by the elastic member to restrain transmission of vibration to the bearing, and fretting abrasion of the bearing due to the vibration is restrained to improve the life of the bearing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a hub unit incorporating a constant velocity joint.

[0002]

2. Description of the Related Art Various types of hub units incorporating a constant velocity joint on the inner periphery of a double row rolling bearing have been proposed by the present applicant.

A conventional hub unit of this type will be described in detail.

A double-row rolling bearing includes a single outer ring having two rows of raceways, a plurality of rolling elements in two rows in the axial direction, and two outer and inner inner rings in the axial direction. A radially outward flange is formed at an axially outer end of the outer inner ring, and a disk rotor and a wheel of a disk brake device are attached to an outer surface of the radially outwardly directed flange.

In other words, the constant velocity joint has its outer ring incorporated into the inner periphery of both inner rings of a double row rolling bearing, while its inner ring is connected to one end of a shaft which is rotationally driven by a power source. Is transmitted to the wheels mounted on the outer surface of the flange of the outer inner ring of the double row rolling bearing.

[0006]

In such a hub unit, the constant velocity joint and the double row rolling bearing are integrally coupled so as to rotate synchronously in order to increase the transmission efficiency of the rotational power via the constant velocity joint. Have been. However, such a coupling, on the other hand, has a structure in which even if the constant velocity joint vibrates minutely, the vibration is easily transmitted to the double row rolling bearing, so that the early stage of the rolling element, the outer ring, and the inner ring constituting the double row rolling bearing is formed. Fretting wear and affect the life of the bearing.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a hub unit having a structure that can reduce or suppress the transmission of vibration from a constant velocity joint to a double row rolling bearing, thereby improving the bearing life.

[0008]

The hub unit of the present invention has a constant velocity joint built into the inner periphery of a double row rolling bearing, and has an axially outer one of two inner rings provided in the double row rolling bearing. A hub unit in which a radially outward flange is formed at an end, and a disk unit and a wheel of a disk brake device are mounted on an outer surface of the flange in a state where the disk rotor and the wheel are applied thereto. The hub unit includes a double row rolling bearing and a constant velocity joint. A vibration damping member is provided therebetween.

According to the hub unit of the present invention, since the vibration from the constant velocity joint to the double row rolling bearing is attenuated by the vibration damping member, its transmission is reduced or suppressed, and the life of the bearing can be improved.

In a preferred embodiment of the present invention, the vibration damping member is an elastic member such as a rubber material. When the vibration damping member is an elastic member, especially a rubber material, heat transfer from the constant velocity joint to the double row rolling bearing is reduced by this rubber, which suppresses temperature rise inside the double row rolling bearing and contributes to longer bearing life it can.

According to a preferred embodiment of the present invention, the inner diameter of both inner races of the double row rolling bearing and the outer diameter of the outer race of the constant velocity joint are formed to be non-circular, and these are fitted through a required gap. The elastic member is interposed in the lever gap.

According to this embodiment, since the inner diameter of both inner races of the double row rolling bearing and the outer diameter of the outer race of the constant velocity joint are formed to be non-circular, multiple rotations of the constant velocity joint are prevented. The row rolling bearing does not rotate synchronously, but relatively rotates with a slight delay while elastically deforming the elastic member, so that the rotational power of the constant velocity joint is transmitted to the double row rolling bearing.
Therefore, it is not necessary to integrally couple the constant velocity joint to the double row rolling bearing, so that the effect of suppressing the transmission of vibration of the constant velocity joint to the double row rolling bearing is further exhibited, which is preferable.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described based on embodiments shown in the drawings.

1 to 3 show an embodiment of the present invention. FIG. 1 is a longitudinal side view of the hub unit, and FIG.
3 is a cross-sectional view taken along the line AA of FIG. 1 when the rotational power is not transmitted to the constant velocity joint, and FIG. 3 is a cross-sectional view taken along the line AA of FIG. 1 when the rotational power is transmitted to the constant velocity joint. . 2 and 3, illustration of the inside of the constant velocity joint is omitted.

The hub unit 1 shown in the figure has a structure in which a constant velocity joint 5 is incorporated in the inner periphery of a double row rolling bearing 3 such as a double row outward angular ball bearing.

The double row rolling bearing 3 has two inner races 7, 9
, A single outer ring 11 having two rows of raceway grooves, a plurality of balls 13 arranged in two rows, and two retainers 15.

A radially outward flange 17 is integrally formed at the axially outer end of the outer inner ring 7 of the double row rolling bearing 3. A disk rotor 19 of a disk brake device and wheels (not shown) are attached to the outer surface of the radially outward flange 17.

A radially outward flange 21 is integrally formed at the axially inner end of the outer race 11 of the double row rolling bearing 3. The radially outward flange 21 is bolted to the vehicle body 23 or the like.

The constant velocity joint 5 is a generally known CV
J (Constant Velocity Join)
t), which includes an inner ring 25, an outer ring 27, a plurality of balls 29, and a retainer 31, and is connected to a vehicle differential device as a power source (not shown) via a shaft 33. . The shaft end of the shaft 33 is spline-fitted to the inner ring 25 of the constant velocity joint 5.

The outer ring 27 of the constant velocity joint 5 is provided at its axially outer end with a radially outwardly directed flange 35, which faces the outer end surface of the outer inner ring 7 of the double row rolling bearing 3 against the flange 35. Abut. In this state, the inner end of the outer race 27 of the constant velocity joint 5 in the axial direction is caulked in a form of being bent radially outward by a rolling caulking method or the like, so that the caulked portion 37 is formed inside the inner race 9 of the double row rolling bearing 3. Press against the inner end face of. Thereby, the double row rolling bearing 3 is positioned in the axial direction with respect to the constant velocity joint 5.

In the hub unit 1 of the embodiment, the inner diameters of the inner rings 7 and 9 of the double row rolling bearing 3 and the outer diameter of the outer ring 27 of the constant velocity joint 5 are changed as shown in FIGS. Are formed in a non-circular shape, and they are fitted to each other with a required gap therebetween. In this gap, for example, an elastic member 39 is densely interposed as a vibration damping member.

The inner diameter of the inner races 7 and 9 of the double row rolling bearing 3 and the outer diameter of the constant velocity joint 5 are not limited to those shown in the drawings as long as they are non-circular.

The vibration damping member is preferably the elastic member 39, but is not limited to this, and may be any member having a function or action capable of damping vibration, for example, a resin.

In the case of a resin, the heat resistance is excellent, the amount of permanent deformation is small, and the resin is hardly deteriorated.

In the embodiment, the elastic members 39 are densely interposed in the axial direction. However, if the vibration of the constant velocity joint 5 can be attenuated before being transmitted to the double row rolling bearing 3, It is not always necessary to interpose densely like
It is also possible to partially interpose a gap between the inner ring portion of the double row rolling bearing 3 and the outer ring portion of the constant velocity joint 5.

In the hub unit 1 having the above configuration, when the outer ring 27 of the constant velocity joint 5 rotates as shown in FIGS. 2 and 3 by the rotational power of the shaft 33, the double row rolling bearing 3 The inner rings 7, 9 do not rotate synchronously, but relatively rotate with a slight delay while elastically deforming the elastic member 39, whereby the rotational power is transmitted to the double row rolling bearing 3. Therefore, in this embodiment, in order to transmit power from the constant velocity joint 5 to the double row rolling bearing 3,
There is no need to combine these two together.

As a result, even if the constant velocity joint 5 vibrates minutely, the vibration is attenuated by the elastic member 39, and the vibration is hardly transmitted to the double row rolling bearing 3. Therefore, in this embodiment, unlike the related art, the double row rolling bearing 3
The fretting wear in the bearing parts constituting the above is suppressed, and the bearing life is improved.

In the illustrated hub unit 1, the tilting fulcrum of the constant velocity joint 5 is arranged at the axial center of the double row rolling bearing 3 so that the constant velocity joint 5 can transmit torque and couple. When this occurs, no bending moment acts on the double row rolling bearing 3.

[0029]

As described above, according to the present invention, a constant velocity joint is incorporated in the inner periphery of the double row rolling bearing, and the axially outer end of one of the two inner rings provided in the double row rolling bearing. A radial outward flange is formed on the
This is a hub unit that is mounted in a state where the disk rotor and wheels of the disk brake device are applied to the outer surface of the flange, and a vibration damping member is provided between the double row rolling bearing and the constant velocity joint, Since the vibration of the constant velocity joint is attenuated by the vibration damping member before being transmitted to the double row rolling bearing, the occurrence of fretting wear of the bearing due to the vibration is suppressed, and the life of the bearing can be improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a hub unit according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA in FIG. 1 when rotational power is not transmitted to the constant velocity joint;

FIG. 3 shows a state in which rotational power is transmitted to a constant velocity joint.
Sectional view along line AA of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hub unit 3 Double row rolling bearing 5 Constant velocity joint 7, 9 Inner ring of double row rolling bearing 11 Outer ring of double row rolling bearing 13 Ball of double row rolling bearing 17 Radial outward flange 19 Disk rotor 27 Constant velocity joint Outer ring 33 Shaft 39 Elastic member

Claims (3)

[Claims] A constant velocity joint is incorporated in the inner periphery of a double row rolling bearing, and a radially outward flange is formed at an axially outer end of one of two inner rings provided in the double row rolling bearing. A hub unit which is mounted in a state where a disk rotor and wheels of a disk brake device are applied to an outer surface of the flange, wherein a vibration damping member is provided between the double row rolling bearing and the constant velocity joint; A hub unit, characterized in that: 2. The hub unit according to claim 1, wherein the vibration damping member is an elastic member. 3. The hub unit according to claim 2, wherein the inner diameter of both inner ring portions of the double row rolling bearing and the outer diameter of the outer ring portion of the constant velocity joint are formed to be non-circular, and they are fitted through a required gap. A hub unit which is fitted and the elastic member is interposed in the gap.