JP2002019411A - Vehicular hub unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance heat radiating performance, and to restrain the thermal degradation of a lubricant used for a heating element in a vehicular hub unit. SOLUTION: In this vehicular hub unit composed of at least a hub wheel 1, a double row rolling bearing 2 arranged on the outer periphery of this hub wheel 1 and a constant velocity joint 3 arranged on the inner periphery of the hub wheel 1, a heat radiating projection part 8 is arranged in a cylindrical shaft part 36 of the constant velocity joint 3. Thus, since heat generated from the double row rolling bearing 2 and the constant velocity joint 3 is efficiently radiated outside from the heat radiating projection part 8, the thermal degradation of the lubricant used for the double row rolling bearing 2 and the constant velocity joint 3 is restrained so that the service life can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hub unit for a vehicle to which a disk rotor and wheels of a disk brake device in a vehicle such as an automobile are attached.

[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.

Here, as a drive wheel type hub unit structure, for example, as shown in FIG. 1 according to the first embodiment of the present invention, a double row rolling bearing 2 is mounted on the outer periphery of a hub wheel 1 and a hub wheel 1 is mounted. A constant velocity joint 3 is attached to the inner circumference of the. On the other hand, as a driven wheel type hub unit structure, for example, as shown in FIG. 3 according to the second embodiment of the present invention, a structure in which a double row rolling bearing 2 is attached to the outer periphery of a hub wheel 1 is usually used. On the outer peripheral surface of such a hub wheel 1, a radially outward flange 11 for mounting a disk rotor 4 or a wheel of a disk brake device in an automobile is provided.

[0004]

In the above conventional example, heat is generated at the double-row rolling bearing 2 and the constant velocity joint 3, so that the lubricant inside thereof is easily deteriorated by heat. Is desired.

In particular, in the case of the driving wheel type, since heat is generated not only from the double row rolling bearing 2 but also from the constant velocity joint 3, it is easy for the two to influence each other and the temperature is likely to rise. The heat is deteriorated more quickly as described above, and the life of the double row rolling bearing 2 and the constant velocity joint 3 is likely to be shortened. FMV-US
ERyoshida As described above, regardless of the type, the heat generated by the constant velocity joint and the double row rolling bearing cannot be avoided, and how this heat is quickly released to the outside to prevent thermal deterioration of the lubricant. It is an issue to control.

[0006] In view of such circumstances, an object of the present invention is to improve heat dissipation and suppress thermal deterioration of a lubricant used for a heating element in a vehicle hub unit.

[0007]

According to a first aspect of the present invention, there is provided a hub unit for a vehicle, in which a double-row rolling bearing is disposed on the outer periphery of a hub wheel, and is integrally formed with an outer end portion of the outer peripheral surface of the hub wheel. The disk wheel and the wheel of the disk brake device are mounted on the outer surface of the radially outward flange in a state where the disk rotor and the wheel are applied. A hollow portion is provided on the inner periphery of the hub wheel, the hollow portion being opened on the flange side. The portion is provided with a plurality of heat radiating protrusions.

A second vehicle hub unit according to the present invention is characterized in that, in the above-mentioned first configuration, the heat-radiating projection is formed integrally with the inner periphery of the hollow portion.

According to a third aspect of the present invention, in the vehicle hub unit according to the first aspect, the heat radiating projection is formed as a separate member fitted and mounted to an inner periphery of the hollow portion. It is characterized by.

A fourth vehicle hub unit according to the present invention is provided with a double row rolling bearing on the outer periphery of the hub wheel, and a constant velocity joint on the inner periphery of the hub wheel.
The outer surface of a radially outward flange formed integrally with the outer end portion of the outer peripheral surface of the hub wheel is mounted in a state where a disk rotor and wheels of a disk brake device are applied thereto, and the outer ring of the constant velocity joint is A bowl-shaped portion for accommodating the tilt guide element on the inner peripheral surface, and a cylindrical shaft portion connected to the small diameter portion of the bowl-shaped portion and spline-fitted to the inner periphery of the hub wheel; A plurality of heat-radiating projections are provided on the inner periphery of the cylindrical shaft portion.

According to a fifth aspect of the present invention, there is provided a vehicle hub unit according to the fourth aspect, wherein the heat radiating projection is formed integrally with the inner periphery of the cylindrical shaft portion.

According to a sixth aspect of the present invention, in the vehicle hub unit according to the fourth aspect, the heat radiating projection is formed as a separate member fitted and mounted on the inner periphery of the cylindrical shaft portion. It is characterized by:

According to a seventh aspect of the present invention, in the vehicle hub unit according to the third or sixth configuration, the heat-radiating projection formed of the separate member is made of a material having excellent heat conductivity. I have.

In summary, in the present invention, by providing a heat-radiating projection for increasing the surface area at the inner peripheral portion of the heat-generating element, the heat dissipation is enhanced and the temperature rise of the heat-generating element is suppressed. I have to.

As a result, thermal deterioration of the lubricant used for the heating element is suppressed for a long period of time.
The durability of the heating element will be extended.

By the way, as in the seventh configuration, more favorable results can be obtained if the heat-radiating projections are made of a material having excellent thermal conductivity.

[0017]

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

FIGS. 1 and 2 show a first embodiment of the present invention. FIG. 1 is a sectional view showing a vehicle hub unit.
FIG. 2 is a sectional view taken along line (2)-(2) of FIG.

The illustrated vehicle hub unit is of a type used on a driving wheel side of an automobile or the like, and has a configuration including at least a hub wheel 1, a double-row rolling bearing 2, and a constant velocity joint 3. ing.

The hub wheel 1 has a hollow structure. A radially outward flange 11 is formed at an axially intermediate portion of an outer peripheral surface of the hub wheel 1, and a female area is provided at a required area on an inner peripheral surface of the hollow portion. The spline is formed, and the raceway surface 12 of the ball 22 group in one row in the double row rolling bearing 2 is formed on the inner end of the outer peripheral surface. Further, bolts 13 for fixing the disc rotor 4 of the disc brake device and wheels (not shown) are mounted in several places on the circumference of the flange 11 in a penetrating state. Note that reference numeral 5
Is a brake pad.

The double row rolling bearing 2 comprises a single outer ring 21 having two rows of raceways, a plurality of balls 22 as rolling elements arranged in two rows, and two crowned retainers 23. The two inner rings that are originally required utilize the outer peripheral surface of the hub wheel 1 and the outer peripheral surface of the constant velocity joint 3. The outer race 21 is formed with a radially outward flange 24 that is bolted to the vehicle body 6 or the like.

The constant velocity joint 3 is called a well-known Zeppa type (Barfield type) constant velocity joint, and includes an outer ring 31, an inner ring 32, a ball 33 and a retainer.
It is composed of The outer ring 31 includes a bowl-shaped part 35 in which the inner ring 32, the ball 33, the retainer 34, and the like are housed and arranged, and a cylindrical shaft part 36 integrally connected to the small diameter side of the bowl-shaped part 35. Have been. A raceway surface 37 of one row of balls 22 in the double-row rolling bearing 2 is provided on the outer peripheral surface of the bowl-shaped portion 35, and a required area on the outer peripheral surface of the cylindrical shaft portion 36 is provided with a hub. Wheel 1
A male spline that is spline-fitted to the female spline is formed. Further, one end of the shaft 7 is spline-fitted to the inner ring 32 and is fixed to the inner ring 32 with a retaining ring or the like. The other end of the shaft 7 is connected to a differential gear of the vehicle via another constant velocity joint (not shown). Attached to the device.

Then, with the double row rolling bearing 2 attached to the outer peripheral surface of the hub wheel 1 and the constant velocity joint 3 attached to the inner peripheral surface of the hub wheel 1, the cylindrical shaft portion of the outer race 31 of the constant velocity joint 3 is mounted. The outer end of the hub wheel 36 is bent radially outward and is caulked against the outer end surface of the hub wheel 1 (caulking portion 38), so that the hub wheel 1 and the outer ring 31 of the constant velocity joint 3 form a double row rolling bearing. 2 in the form of being pinched from the axial direction, and a double row rolling bearing 2
A required preload (compressive stress) is applied to the substrate.

In such a vehicle hub unit, the rotational power of the shaft 7 is transmitted to wheels (not shown) attached to the hub wheel 1 via the constant velocity joint 3.

The first embodiment is characterized in that the heat radiating projections 8 are integrally formed at several locations on the inner peripheral surface of the cylindrical shaft portion 36 of the constant velocity joint 3 by cold forging or the like. There is.

As described above, the outer ring 31 of the constant velocity joint 3
If the heat radiating protrusion 8 is provided for the cylindrical shaft portion 36 in the above, the surface area increases, and the heat radiating action is improved. Therefore, the heat generated from the constant velocity joint 3 is transmitted to the hub wheel 1 and radiated to the outside from the heat-radiating projection 8 of the hub wheel 1. Also, the heat generated from the double row rolling bearing 2 is transmitted to the hub wheel 1 in the same manner as described above, and is radiated to the outside from the heat radiating projection 8 of the hub wheel 1. As a result, thermal deterioration of the lubricant used for the double row rolling bearing 2 and the constant velocity joint 3 is suppressed, so that the double row rolling bearing 2 and the constant velocity joint 3 are stably lubricated for a long period of time. And contribute to the improvement of their life.

FIGS. 3 and 4 show a second embodiment of the present invention. FIG. 3 is a sectional view showing a vehicle hub unit;
FIG. 4 is a sectional view taken along line (4)-(4) of FIG.

In the second embodiment, the heat radiation projection 8 is not formed integrally with the cylindrical shaft portion 36 of the constant velocity joint 3 as in the first embodiment, but is formed separately with respect to the cylindrical shaft portion 36. The heat dissipation cap 9 of the body is fitted and mounted by press fitting.

Specifically, as shown in FIG. 3, the heat dissipating cap 9 is made of, for example, stainless steel or the like and is formed into a cylindrical shape with a bottom by pressing, and a plurality of cuts are formed at several locations on the bottom surface. A raising piece 91 is provided. By providing the cut-and-raised pieces 91, the same number of openings 9
2 are provided.

In this case, as in the first embodiment, the heat generated from the constant velocity joint 3 and the heat generated from the double row rolling bearing 2 are generated by the heat dissipation cap 9 mounted on the inner peripheral surface of the cylindrical shaft portion 36 of the constant velocity joint 3. The generated heat is radiated to the outside, and their temperature rise is suppressed. Therefore, double row rolling bearing 2 and constant velocity joint 3
The thermal deterioration of the lubricant used for the tire is suppressed, and the life of the lubricant can be improved.

The heat dissipation cap 9 is not a part that processes the inner periphery of the cylindrical shaft part 36 of the outer race 31 of the constant velocity joint 3, but is a separate part that can be easily obtained by press working. Become. In addition, since the heat radiation cap 9 is detachable, there is the convenience that replacement can be easily performed.

FIG. 5 is a sectional view of a vehicle hub unit according to Embodiment 3 of the present invention. In the third embodiment, the invention is applied to a vehicle hub unit of a type used on a driven wheel side of an automobile.

That is, the vehicle hub unit here comprises the hub wheel 1 and the double row rolling bearing 2 and does not have the constant velocity joint 3 shown in the first embodiment.

The hub wheel 1 and the double-row rolling bearing 2 according to the third embodiment have basically the same configuration as that described in the first embodiment, but are slightly different in details.
That is, the hub wheel 1 has a solid structure, and has a structure in which a raceway surface serving as one inner ring of the double-row rolling bearing 2 is formed on the outer peripheral surface of the shaft portion. Has a single inner ring 25.

The inner end of the shaft portion of the hub wheel 1 is bent radially outward to be caulked against the end surface of the inner ring 25 of the double row rolling bearing 2 (the caulked portion 1).
5) As a result, the double row rolling bearing 2 is integrated with the hub wheel 1.

In the third embodiment, in order to dissipate heat generated from the double row rolling bearing 2 in the above-described premise,
On the inner periphery of the hollow portion 14 at the outer end of the hub wheel 1,
As in the first embodiment, the heat radiation projections 8 are characterized by being integrally formed by cold forging or the like.

In this case, the heat generated from the double-row rolling bearing 2 is transmitted to the hub wheel 1 and radiated to the outside by the heat-radiating projection 8 of the hub wheel 1. The rise can be suppressed. Therefore, the thermal deterioration of the lubricant used for the double-row rolling bearing 2 is suppressed, so that the double-row rolling bearing 2 is stably lubricated for a long period of time, thereby contributing to the improvement of the service life. .

FIG. 6 is a sectional view of a vehicle hub unit according to Embodiment 4 of the present invention. The hub unit for a vehicle according to the fourth embodiment is of a type used on the driven wheel side of an automobile similarly to the third embodiment, and is similar to the second embodiment.
The same technical philosophy is applied.

Specifically, the heat dissipation cap 9 is fitted and mounted in the hollow portion 14 of the hub wheel 1 by press fitting.

In this case, similarly to the third embodiment, the heat generated from the double row rolling bearing 2 is transmitted to the hub wheel 1 and the heat dissipating cap 9 mounted on the hub wheel 1 is provided.
As a result, the temperature rise of the double row rolling bearing 2 can be suppressed. Other than that, the maintenance of replacement of the heat radiation cap 9 is the same as that of the second embodiment.

It should be noted that the present invention is not limited to only the above embodiment, and various applications and modifications are conceivable.

(1) In the first to fourth embodiments,
The cut-and-raised piece 91 of the heat dissipation convex portion 8 and the heat dissipation cap 9 is
The propeller can be twisted in the longitudinal direction (axial direction). In this case, since the fan function of generating a wind with the rotation of the hub wheel 1 and the outer ring 31 of the constant velocity joint 3 is exhibited, the heat dissipation is further improved. The number and shape of the cut-and-raised pieces 91 of the heat-radiating projections 8 and the heat-radiating cap 9 can be considered variously and are not particularly limited.

(2) In the second and fourth embodiments, the heat dissipation cap 9 can be formed of a material having excellent heat conductivity (eg, copper or copper alloy). In this case, the heat generated from the double row rolling bearing 2 and the constant velocity joint 3 is more efficiently dissipated, and more preferable results are obtained.

[0044]

According to the first to seventh aspects of the present invention, the heat generated by the operation is efficiently dissipated, so that heat is not trapped in the heat generating elements such as the double row rolling bearing and the constant velocity joint. And the overall temperature rise is suppressed. As a result, thermal deterioration of the lubricant used for the double-row rolling bearing and the constant velocity joint is suppressed, and the lubricating ability is stabilized, so that the life of the double-row rolling bearing and the constant velocity joint can be improved. As a result, a highly reliable vehicle hub unit can be provided.

In particular, according to the third and sixth aspects of the present invention, since the heat radiating projection is formed as a separate component from the components of the hub unit, it is advantageous in terms of cost as compared with the case of processing the components of the hub unit. In addition, maintainability such as replacement is improved.

According to the seventh aspect of the present invention, the third and sixth aspects are provided.
Since the separate heat-radiating projections in are made of a material with excellent thermal conductivity, the heat-radiating properties will further increase,
This can greatly contribute to the improvement of the life of double row rolling bearings and constant velocity joints.

[Brief description of the drawings]

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

FIG. 2 is a sectional view taken along line (2)-(2) of FIG.

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

4 is a sectional view taken along line (4)-(4) of FIG.

FIG. 5 is a sectional view showing a vehicle hub unit according to a third embodiment of the present invention.

FIG. 6 is a sectional view showing a vehicle hub unit according to a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hub wheel 2 Double row rolling bearing 3 Constant velocity joint 4 Disk rotor 8 Radiation convex part 9 Radiation cap 31 Outer ring of constant velocity joint 36 Cylindrical shaft part of outer ring

Claims (7)

[Claims] A double-row rolling bearing is disposed on an outer periphery of a hub wheel, and a disk rotor of a disk brake device is provided on an outer surface of a radially outward flange integrally formed with an outer end of an outer peripheral surface of the hub wheel. And a vehicle hub unit mounted in a state where wheels are applied, wherein a hollow portion is provided on an inner periphery of the hub wheel, the hollow portion being opened on a flange side thereof, and a plurality of heat radiation convex portions are provided in the hollow portion. A hub unit for a vehicle, comprising: 2. The vehicle hub unit according to claim 1, wherein the heat radiating projection is formed integrally with an inner periphery of the hollow portion. 3. The vehicle hub unit according to claim 1, wherein the heat-radiating projection is formed on a separate member fitted and attached to an inner periphery of the hollow portion. Hub unit. 4. A double row rolling bearing is provided on the outer periphery of a hub wheel.
In addition, a constant velocity joint is provided on the inner periphery of the hub wheel, and a disk rotor or a wheel of a disk brake device is provided on an outer surface of a radially outward flange formed integrally with an outer end of an outer peripheral surface of the hub wheel. Wherein the outer ring of the constant velocity joint is connected to a bowl-shaped portion that accommodates a tilt guide element on an inner peripheral surface and a small-diameter portion of the bowl-shaped portion. And a cylindrical shaft portion that is spline-fitted to the inner periphery of the hub wheel, and a plurality of heat radiation protrusions are provided on the inner periphery of the cylindrical shaft portion. Hub unit. 5. The vehicle hub unit according to claim 4, wherein said heat-radiating projection is formed integrally with an inner periphery of a cylindrical shaft portion. 6. The vehicle hub unit according to claim 4, wherein the heat-radiating projection is formed on a separate member fitted and mounted on the inner periphery of the cylindrical shaft portion. Hub unit. 7. The vehicle hub unit according to claim 3, wherein the heat radiating projection formed of the separate member is made of a material having excellent thermal conductivity.