JP2002174256A - Hub unit for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problems in a conventional hub unit for a vehicle that foreign matter such as mud water enters a double row rolling bearing easily, the lubricity of a lubricant applied into the inside of the double row rolling bearing is easily lost, and service life of the double row rolling bearing is shortened because the hub unit for the vehicle has such configuration that a contact type seal comes into contact with an outer peripheral face of a hub wheel or an outer peripheral face of a bowl-shaped part of an constant velocity joint merely as a seal mechanism. SOLUTION: An annular seal part 41 extended so as to cover an end part of an outer face 16 of the double row rolling bearing 6 is formed in a non- contact type seal member 37 of a seal device 35, and its tip part is arranged with a slight clearance on an outer peripheral face of the outer ring 16 of the double row rolling bearing 6 to prevent the entry of the foreign matter such as mud water into the clearance 31. When the bowl-shaped part 15 of the constant velocity joint 5 rotates around a shaft axis C, the non-contact type seal member 37 rotates around the shaft axis C in accordance with the rotation of the bowl-shaped part to improve the sealing property.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a hub unit for a vehicle.

[0002]

2. Description of the Related Art In general, a vehicle hub unit is roughly classified into a type used on a driving wheel side of a vehicle such as an automobile and a type used on a driven wheel side.

As shown in FIG. 5, a hub unit 50 for a drive wheel type vehicle has a hub wheel 5 on which a wheel or a disk rotor of a disk brake device is mounted.
1, a constant velocity joint 52 and a double row rolling bearing 53 that rotatably supports these around an axis. In addition, a shaft portion 54A integrally formed on an outer ring of the constant velocity joint 52, that is, a shaft-shaped outer end side (vehicle outboard side) of a main body bowl-shaped portion (hereinafter, simply referred to as a "bowl-shaped portion") 54.
Are spline-fitted into the center hole of the hub wheel 51,
The double-row rolling bearing 53 is disposed so as to extend over the outer peripheral surfaces of the hub-shaped portion 54 of the hub wheel 51 and the constant velocity joint 52.

The outer peripheral surface of the hub wheel 51 or the constant velocity joint is provided on the outer end side in the axial center of the outer race 55 of the double row rolling bearing 53 and on the inner end side in the axial direction of the outer race 55 (inboard side of the vehicle). A contact-type seal 56 for preventing foreign substances such as muddy water from entering the double-row rolling bearing 53 in contact with the outer peripheral surface of the bowl-shaped portion 54 of 52 is attached.

[0005]

In the conventional vehicle hub unit 50, the outer peripheral surface of the hub wheel 51 or the bowl-shaped portion 5 of the constant velocity joint 52 is used as a sealing mechanism.
Since the contact type seal 56 is only in contact with the outer peripheral surface of the double row rolling bearing 53, foreign matter such as muddy water easily enters the double row rolling bearing 53. The lubricity declined early and the life of the double row rolling bearing 53 was shortened.

In addition, since the double row rolling bearing 53 and the constant velocity joint 52 are mounted close to the hub wheel 51, heat generated from the double row rolling bearing 53 and the constant velocity joint 52 is mutually generated. The temperature is likely to increase synergistically during use, and the contact-type seal 56
As a result, the interior of the bearing 53 is substantially sealed, so that the lubricant applied to the interior of the double-row rolling bearing 53 is thermally degraded at an early stage, and the lubricity tends to deteriorate. Therefore, the life of members such as the double row rolling bearing 53 and the constant velocity joint 52 has been shortened.

Accordingly, an object of the present invention is to provide a vehicle hub unit that can solve the above-mentioned problems.

[0008]

According to the present invention, a constant velocity joint for tiltably supporting a hub wheel for mounting a wheel is provided integrally with a large diameter outer ring and one end thereof. A rotating shaft having a small diameter, wherein the rotating shaft is integrally inserted into and supported by the hub wheel, and a rolling bearing for rotatably supporting the hub wheel around its axis is provided. An end surface of the outer race and an end surface of the hub wheel are arranged with a predetermined gap therebetween in the axial direction, and a contact-type seal member and a non-contact-type seal for preventing foreign matter from entering the inside of the rolling bearing and the gap. The non-contact type sealing member is provided such that a base is attached near the gap on the outer peripheral surface of the outer ring of the constant velocity joint and extends so as to cover the end of the outer ring of the rolling bearing. Having a sealing portion of the annular, the seal portion, the tip portion is disposed at a slight gap in the circumferential direction on the outer ring outer circumferential surface of the rolling bearing.

The core of the contact-type seal member is fixed to the end of the outer race of the rolling bearing, and the contact piece of the contact-type seal member fixed to the core is passed to the base of the non-contact-type seal member. Have been contacted.

[0010] Further, on the outer peripheral surface of the seal portion of the non-contact type seal member, there is formed an uneven portion for guiding the flow of air to the outer ring side of the rolling bearing when the outer ring of the constant velocity joint rotates.

In the above configuration, when the constant velocity joint rotates around the axis, the non-contact type sealing member also rotates around the axis, and the tip of the sealing portion of the non-contact type sealing member has Since a small gap in the circumferential direction is arranged on the outer peripheral surface of the outer ring of the rolling bearing, foreign substances such as muddy water enter the gap between the end surface of the outer ring of the constant velocity joint and the end surface of the hub wheel. To prevent.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, a vehicle hub unit 1 according to a first embodiment of the present invention is used on a driving wheel side of an automobile, and has a hub wheel 2 to which wheels (not shown) are attached. A small-diameter shaft portion 4 (rotating shaft) is inserted into an insertion hole 3 formed in the hub wheel 2.
And a constant velocity joint 5 formed on the vehicle outboard side, a rotating member R is provided, and a double row rolling bearing 6 for rotatably supporting the hub wheel 2 around the axis C is provided.

A male spline which is spline-fitted to a female spline of the hub wheel 2 is formed on the outer peripheral surface of the shaft portion 4.
The nut 4a is tightened by the nut 4a to prevent movement in the direction of the axis C.

The hub wheel 2 is provided with a flange 7 projecting radially outward in the middle of the outer peripheral surface thereof.
A brake disc rotor 11 is fixed to the flange 7 via a hub bolt 7a.

Reference numeral 13 in the drawing denotes a brake pad for braking the rotation of the brake disk rotor 11.

The constant velocity joint 5 is of a well-known type called a Zeppa type (Barfield type), and has a bowl-shaped section 15 having a bowl-shaped cross section in which the shaft section 4 is integrally formed on one side. An inner ring 17 to which a drive shaft 22 connected to the engine is inserted and fixed, a ball 10 for tilting and guiding the hub wheel 2 with respect to the drive shaft 22 and a retainer 20 thereof are provided.

One end of the drive shaft 22 is spline-fitted to the inner race 17, and the drive shaft 22 is fixed to the inner race 17 with a retaining ring (omitted). The other end of the drive shaft 22 is attached to a vehicle differential via another constant velocity joint (not shown).

The hub wheel 2 is fitted with an inner race member 25 having a single track on the vehicle inboard side by a caulking portion 2b at the end of the hub wheel 2. Then, the caulked portion 2b and the bowl-shaped portion 1 of the constant velocity joint 5 are formed.
5, a predetermined gap 31 is provided.

The double row rolling bearing 6 has a single outer ring 16 having two rows of raceway grooves, and an axially outer end face 16 a of the outer ring 16 is arranged at a position close to the flange 7 of the hub wheel 2. ing. Furthermore, the double row rolling bearing 6
A plurality of balls 9a and 9b as rolling elements arranged in two rows
And two crown-shaped retainers 23, of which two inner rings are essentially required, one using the raceway surface of the hub wheel 2 and the other using the outer peripheral surface of the inner race member 2b as the raceway surface. It has been. In the middle of the outer peripheral surface of the outer race 16, a knuckle 12 fixed to the vehicle body is provided with a bolt 12a.
A radially outwardly directed flange 8 to be stopped is formed.

An annular contact-type seal member 32 for sealing a gap between the outer ring 16 of the double row rolling bearing 6 on the vehicle outboard side and the flange 7 of the hub wheel 2 is provided. It comprises a metal core 33 fixed to the inner peripheral surface of the outer ring 16 and a contact piece 34 that contacts the outer peripheral surface of the hub wheel 2.

A sealing device 35 for sealing the gap 31 is provided. The sealing device 35 includes a contact-type sealing member 36 and a non-contact-type sealing member 37, and the contact-type sealing member 36 A core 38 fixed to the inner peripheral surface of the outer ring 16 and a contact piece 40 fixed to the core 38 and in contact with the outer peripheral surface of the inner ring member 25 and a base 39 of a non-contact type sealing member 37 described later. It is configured.
The outer diameter of the core portion 38 of the contact seal member 36 is formed smaller than the diameter of the outer ring 16.

The non-contact type sealing member 37 includes the base 39 fitted on the stepped portion of the bowl-shaped portion 15 of the constant velocity joint 5, and the outer race 16 of the double row rolling bearing 6 from the outer peripheral end of the base 39. Has an annular seal portion 41 which is curved and extended so as to cover the end portion of the outer ring 16 of the double row rolling bearing 6 with a slight gap at the tip end thereof. Are located. Further, the sealing portion 41
Is a bowl-shaped part 15 of the constant velocity joint 5
The air flow during the rotation of the outer ring 16 of the double row rolling bearing 6
An uneven portion 42 inclined with respect to the axis C is formed on the side, that is, in a direction of guiding from the vehicle inboard side to the vehicle outboard side, and the unevenness is arranged along the axis C direction.

In the vehicle hub unit 1 having the above structure, the rotational power of the drive shaft 22 is transmitted to the constant velocity joint 5 and the hub wheel 2, that is, the rotating member R, and transmitted to the wheels to rotate.

Here, the operation of the sealing device 35 will be described. The non-contact type sealing member 37 of the sealing device 35 includes:
The double row rolling bearing 6 has an annular seal portion 41 extended so as to cover the end of the outer ring 16, and the distal end thereof is slightly attached to the outer peripheral surface of the outer ring 16 of the double row rolling bearing 6 in the circumferential direction. Since it is arranged with a large gap, foreign substances such as muddy water are unlikely to enter the gap 31. When the bowl-shaped portion 15 of the constant velocity joint 5 rotates around the axis C, the non-contact type sealing member 37 rotates around the axis C accordingly. And
The rotation of the non-contact type sealing member 37 about the axis C further improves the sealing performance (labyrinth action).

In addition, the uneven portion 4 is formed on the peripheral surface of the seal portion 41.
2, the uneven portion 42 moves (rotates) as the non-contact type seal member 37 rotates around the axis C, so that air flows around the outer periphery of the seal portion 41,
In particular, a flow from the vehicle inboard side to the vehicle outboard side occurs, and the movement of the uneven portion 42 and the flow of the air are combined to remove foreign matter from the vicinity of the seal portion 41 and prevent foreign matter from entering the gap 31. Can be prevented.

Further, the base 3 of the non-contact type sealing member 37
9. Contact type sealing member 36 having a contact piece 40 that contacts
Is provided, foreign matter can be reliably prevented from entering the gap 31 even by the contact-type sealing member 36.

The outer diameter of the contact-type seal member 36 is smaller than the diameter of the outer race 16, so that the vehicle hub unit 1 can be easily assembled to the knuckle 12.

As described above, according to the first embodiment of the present invention, the non-contact type sealing member 37 of the sealing device 35 covers the end of the outer ring 16 of the double row rolling bearing 6 from the vehicle inboard side. An extended seal portion 41 was formed, and the tip end thereof was arranged with a slight gap on the outer peripheral surface of the outer ring 16 of the double row rolling bearing 6, and an uneven portion 42 was formed on the peripheral surface of the seal portion 41. Accordingly, it is possible to reliably prevent foreign matter such as muddy water from entering the gap 31 and prevent corrosion of the fitting portion between the shaft portion 4 and the hub wheel 2 by preventing foreign matter from entering the gap 31. Further, the life of the double row rolling bearing 6 can be extended.

Further, since the air flow is generated around the outer periphery of the seal portion 41 by the movement of the concave and convex portion 42, the temperature rise of the non-contact type seal member 37 is suppressed. Even if 40 is in contact with the base 39 of the non-contact type sealing member 37, the contact type sealing member 3
The temperature rise of the bearing 6 can be suppressed to extend the service life, and the deterioration of the lubricant in the double row rolling bearing 6 can be prevented.

Next, a second embodiment of the present invention will be described with reference to FIG. The vehicle hub unit 1 according to the second embodiment of the present invention is provided with a rotation for detecting a rotation speed of a wheel at a position facing the uneven portion 42 of the seal portion 41 on the vehicle inboard side panel surface of the knuckle 12. Sensor 45
Is attached. This rotation sensor 45
The moving speed of the uneven portion 42 is detected as a signal, and this signal is output to a control device (not shown). Based on this signal, the control device calculates the rotational speed of the wheels. The other configuration and operation and effect are the same as those in the first embodiment, and thus will not be described.

In the above embodiment, the concave and convex portions 42 of the seal portion 41 are arranged along the axis C. However, the present invention is not limited to this, and as shown in FIG. It may be formed so as to be inclined. In this case, the rotation of the non-contact type sealing member 37 can more reliably generate an air flow on the vehicle outboard side, and can remove foreign matters.

[0032]

As is apparent from the above description, the present invention is intended to prevent foreign matter from entering the inside of the rolling bearing and the gap between the end face of the outer ring of the constant velocity joint and the end face of the hub wheel. Is provided, and the non-contact type seal member of the seal device is provided with an annular seal portion extended so as to cover the end of the outer ring of the rolling bearing, so that the seal portion rotates with the rotation of the constant velocity joint. As a result, the sealing property is improved, and foreign matter can be prevented from entering the gap, and therefore, the life of members such as rolling bearings can be extended.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a vehicle hub unit according to a first embodiment of the present invention.

FIG. 2 is a partially enlarged perspective view of the non-contact type sealing member.

FIG. 3 is a schematic sectional view of a vehicle hub unit according to a second embodiment of the present invention.

FIG. 4 is a partially enlarged perspective view of a non-contact type sealing member showing another embodiment.

FIG. 5 is a schematic sectional view of a conventional vehicle hub unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vehicle hub unit 2 Hub wheel 2b Caulking part 5 Constant velocity joint 6 Double row rolling bearing 12 Knuckle 15 Outer ring 22 Drive shaft 31 Gap 35 Sealing device 36 Contact type seal member 37 Non-contact type seal member 41 Seal portion 42 Irregular portion

Claims (3)

[Claims] A constant velocity joint for tiltably supporting a hub wheel for mounting a wheel includes a large-diameter outer ring and a small-diameter rotary shaft integrally provided at one end thereof. The rotation shaft is integrally inserted and supported,
A rolling bearing for rotatably supporting the hub wheel around its axis is provided, and an end surface of an outer ring of the constant velocity joint and an end surface of the hub wheel are arranged with a predetermined gap in an axial direction, A seal device including a contact-type seal member and a non-contact-type seal member for preventing foreign matter from entering the inside of the rolling bearing and the gap is provided, and the non-contact-type seal member is provided on an outer periphery of a constant velocity joint. A base portion is attached near the gap on the surface and has an annular seal portion extended so as to cover the end of the outer ring of the rolling bearing. A hub unit for a vehicle, wherein the hub unit is arranged with a small gap in a circumferential direction. 2. The contact-type seal member has a core portion fixed to an end of an outer ring of the rolling bearing, and a contact piece of the contact-type seal member fixed to the core portion passes to a base of the non-contact-type seal member. The vehicle hub unit according to claim 1, wherein the hub unit is in contact with the hub unit. 3. A concavo-convex portion is formed on an outer peripheral surface of a seal portion of the non-contact type seal member to guide an air flow to the outer ring side of the rolling bearing when the outer ring of the constant velocity joint rotates. The vehicle hub unit according to claim 1 or 2, wherein: