JP2001304285A - Constant velocity universal joint and bearing system for wheel using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a clearance diameter of a constant velocity universal joint installing a large diametrical side end part of a boot on an outer ring and to improve a connecting and disconnecting property to and from a car body of a wheel bearing system in which this constant velocity universal joint is built. SOLUTION: The wheel bearing system is constituted by providing an extended part 28 on an opening end part of the outer ring 3 of the constant velocity universal joint 1, providing a ring installation part 29 on an inner peripheral surface of the extended part and press-fitting and fixing the large diametrical side end part 14 of the boot 12 on this installation part 29.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a constant velocity universal joint and a wheel bearing device using the same, and more particularly to a boot mounting structure.

[0002]

2. Description of the Related Art In a constant velocity universal joint, a synthetic resin or rubber boot is mounted between an outer ring and a drive shaft in order to prevent leakage of internal lubricating grease.

FIG. 5 shows a constant velocity universal joint 51 and a wheel bearing 52.
Is a conventional wheel bearing device configured by combining the joint body 63 and the boot 62.
Combination with

The joint body 63 has a curved track groove 5 on each of the spherical inner surface of the outer ring 53 and the spherical outer surface of the inner ring 54.
5, 55 'are formed at equal intervals in the circumferential direction, a ball 56 for torque transmission is incorporated between both track grooves 55, 55', and a retainer 57 of the ball 56 is connected to the outer ring 53 and the inner ring 54.
And contact guidance between Outer ring 53 above
An outer ring stem 58 is integrally provided on the closed end surface of the rim, and a spline 59 is formed on the outer diameter surface thereof. A drive shaft 61 is inserted into and fixed to the inner race 54 from the opening end side of the outer race 53. The inner race 54 and the drive shaft 61 are integrally bent with respect to the outer race stem 58 to transmit torque with a predetermined operating angle. Is available.

[0005] The boot 62 includes the outer ring 53 and the inner ring 54.
In order to prevent leakage of grease filled between the
3 is mounted between the outer diameter surface of the open end and the drive shaft 61. The boot 62 is made of synthetic resin or rubber, and is provided with a large-diameter end 64 attached to the outer diameter surface of the outer ring 53 at one end of the bellows portion 60 and attached to the drive shaft 61 at the other end. A small-diameter end 65 is provided. Each of these ends 64, 65 is tightly fixed by a steel-made boot band 66, 66 wound around its outer peripheral surface.

On the other hand, the wheel bearing 52 is provided with an outer member 67,
It has an inner member 68, and the inner member 68 is a hub wheel 68a.
And a bearing inner ring 68b fitted and fixed to the outer diameter surface of the inner end of the hub ring 68a. The outer-side rolling element 70a is provided between the outer member 67 and the raceway surface of the facing surface of the hub wheel 68a on the outer side, and the outer member 67 is provided on the inner side.
The inner rolling element 70b is incorporated between the bearing surface of the bearing inner ring 68b and the bearing surface. The outer member 67 is provided with a vehicle body mounting flange 72 for connecting to a knuckle 71 of the vehicle body, and the hub wheel 68a is provided with a wheel mounting flange 73 for mounting a wheel. A spline groove 74 is formed on the inner diameter surface of the hub wheel 68a.

The above constant velocity universal joint 51 has its outer ring stem 58 inserted into the inner diameter surface of the hub wheel 68a and the spline 5
9 and the spline groove 74 and the hub wheel 68
The nut 75 is fastened to the part protruding outside of FIG.

The vehicle body mounting flange 72 is connected and fixed to a knuckle 71 by a bolt 76, and a wheel is mounted by a bolt 77 fixed to the wheel mounting flange 73.

The wheel bearing device having the above-described configuration transmits the torque applied to the outer ring 53 of the constant velocity universal joint 51 to the hub wheel 68a via the outer ring stem 58.

[0010]

In the above-described wheel bearing device, the large-diameter end 64 of the boot 62 of the constant velocity universal joint 51 is attached to the outer diameter surface of the outer ring 53.
The minimum clearance diameter in assembling the constant velocity universal joint 51 is
In many cases, the outer diameter of the outer ring 53 is a dimension obtained by adding the thickness of the boot 62 or the protrusion 78 of the boot band 66.

On the other hand, in the assembly line of an automobile, considering the case where the above-mentioned wheel bearing device is incorporated into the knuckle 71 or the case where the device is removed from the knuckle 71 during repair, the clearance of the constant velocity universal joint 51 is larger than the knuckle inner diameter A. Since the diameter has to be small, the design of the wheel bearing device is sometimes restricted. Further, when the projecting portion 78 of the boot band 66 protrudes from the knuckle inner diameter A, there is no problem because the boot band 66 is attached later at the time of assembling, but it is necessary to take steps such as removing it in advance at the time of repair.

In view of this, the present invention provides a constant-velocity universal joint that maintains the size of the outer race as before, while preventing the thickness of the boot and the height of the boot band from affecting the clearance diameter. It is an object of the present invention to improve the convenience of attaching / detaching a wheel bearing device incorporating a constant velocity universal joint to / from a vehicle body.

[0013]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention comprises a joint body and boots mounted between the outer ring and a drive shaft, and the open end of the outer ring is provided. A constant-velocity universal joint in which the large-diameter end of the boot is attached to the drive shaft and the small-diameter end of the boot is attached to the drive shaft. And a large diameter end of the boot is press-fitted and fixed to the mounting portion.

According to the above configuration, the large-diameter end of the boot attached to the open end of the outer race of the constant velocity universal joint is within the outer diameter of the outer race, so that the clearance diameter of the constant velocity universal joint is reduced. Is done. Also, a boot band is not required.

It is possible to adopt a configuration in which a pushing flange is provided on the outer diameter surface of the large-diameter end portion of the boot, and the flange is pressed against the end surface of the mounting portion. In this case, the pushing flange serves as a portion against which the jig is pressed when the boot is attached to the mounting portion, and at the same time, reinforces the large-diameter end portion.

Further, the reinforcing member may be provided with a reinforcing flange integrated with the pushing flange at one end of the cylindrical portion, thereby reinforcing the pushing flange.

As means for imparting elasticity to the cylindrical portion of the above-mentioned reinforcing member, a slit is provided at a plurality of positions of the cylindrical portion, the end of which is opposite to the reinforcing flange and whose outer end surface is open to the outside.
It is possible to adopt a configuration in which engagement pieces are provided at a plurality of positions of the cylindrical portion by cutting and raising the reinforcing flange side.

The constant velocity universal joint having the above configuration has a configuration in which the open end of the outer race is extended in the axial direction by an amount corresponding to the mounting portion, so that the operating angle is slightly reduced. Therefore, since it does not have a steering mechanism like the front wheels, it is suitable for rear wheels of FR vehicles or 4WD vehicles that do not require a large operating angle. In addition, the present invention can be applied to the front wheels of an FF vehicle or a 4WD vehicle by being used together with a four-wheel steering mechanism.

The present invention also includes a wheel bearing device configured by combining the above constant velocity universal joint with a wheel bearing portion. As described above, since the clearance diameter of the constant velocity universal joint in this case is reduced, it can be made smaller than the inner diameter of the knuckle on the vehicle body side. This simplifies the attaching / detaching operation when attaching the wheel bearing device to the knuckle of the vehicle body or removing the bearing device during repair.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, the wheel bearing device according to the embodiment is also configured by a combination of a constant velocity universal joint 1 and a wheel bearing unit 2 as in the conventional case. The constant velocity universal joint 1 includes a combination of a joint body 13 and a boot 12.

The joint body 13 has curved track grooves 5, 5 'on the spherical inner surface of the outer race 3 and the spherical outer surface of the inner race 4, respectively.
Are formed at equal intervals in the circumferential direction, a ball 6 for torque transmission is incorporated between both track grooves 5 and 5 ', and a retainer 7 of the ball 6 is contact-guided between the outer ring 3 and the inner ring 4. ing. An outer ring stem 8 is integrally provided on the closed end face of the outer ring 3, and a spline 9 is formed on the outer diameter surface. A drive shaft 11 is provided on the inner ring 4.
The inner ring 4 and the drive shaft 11 are integrated with each other and can be freely bent with respect to the outer ring stem 8 so that torque can be transmitted at a predetermined operating angle.

The boot 12 is mounted between the outer diameter surface of the open end of the outer race 3 and the drive shaft 11 in order to prevent the grease filled between the outer race 3 and the inner race 4 from leaking. The boot 12 is made of synthetic resin or rubber and has a large-diameter end 14 to which the outer diameter surface of the outer ring 3 is attached, and a small-diameter end 15 to be attached to the drive shaft 11, and a bellows portion therebetween. 19 are formed. The point that the small-diameter end 15 is tightly fixed to the outer diameter surface of the drive shaft 11 with a boot band 16 made of a steel plate is the same as the conventional case, but the structure of the large-diameter end 14 and the outer ring to which it is attached The structure of the opening end side of 3 is different from the conventional case. This will be described later.

On the other hand, the wheel bearing section 2 has an outer member 17 and an inner member 18, and the inner member 18 is fitted and fixed to a hub wheel 18a and an outer diameter surface at an inner end portion of the hub wheel 18a. Of the bearing inner ring 18b. On the outer side, the outer rolling element 20a is provided between the raceway grooves on the facing surface of the outer member 17 and the hub wheel 18a, and on the inner side, the inner rolling element 20b is provided between the raceway grooves on the facing surface of the outer member 17 and the bearing inner ring 18b. Be incorporated. The outer member 17 is provided with a vehicle body-side mounting flange 22 for connecting to a knuckle 21 of the vehicle body, and the hub wheel 18a is provided with a wheel-side mounting flange 23 for mounting a wheel. A spline groove 24 is formed on the inner surface of the hub wheel 18a.

In the above constant velocity universal joint 1, the drive shaft 11 is inserted into the inner diameter surface of the hub wheel 18a, the spline 9 and the spline groove 24 are engaged, and the hub wheel 1
The portion protruding to the outside of 8a is tightened and fixed with a nut 25.

The vehicle body side mounting flange 22 is connected and fixed to the knuckle 21 by bolts 26, and the wheels are mounted by bolts 27 fixed to the wheel side mounting flanges 23.

The wheel bearing device having the above-described structure transmits the torque applied to the outer ring 3 of the constant velocity universal joint 1 to the hub wheel 18a via the outer ring stem 8.

As shown in FIG. 2, the opening end of the outer race 3 extends from the opening end of the conventional track groove 5 to the boot 12 side by a dimension b with a constant thickness a. Is provided. The outer diameter surface of the extension portion 28 is continuous from the outer diameter surface of the outer race 3 without a step, but the inner diameter side is thinner by the step c at the track groove 5 portion. The inner diameter surface of the extension portion 28 forms an annular mounting portion 29 for mounting the large-diameter end portion 14 of the boot 12. An engagement groove 30 is formed at an inner end of the mounting portion 29.

The large-diameter end 14 of the boot 12 and the bellows 19
Between them, a pushing flange 31 is formed on the outer diameter surface of the boot 12. This pushing flange 31
Is a portion to which a jig is pressed when the large-diameter end portion 14 is mounted on the mounting portion 29.

A metal reinforcing member 32 having an L-shaped cross section is formed on the surface formed by the outer diameter surface of the large-diameter end portion 14 and the pushing flange 31 continuous with the inner end thereof (see FIG. 2B). ) Are integrated by insert molding. The reinforcing member 32 includes a reinforcing cylindrical portion 33 and a reinforcing flange 34 formed outward at one end thereof. The reinforcing cylindrical portion 33 is integrated with the outer diameter surface of the large-diameter end portion 14, and the reinforcing flange 34 is integrated with the pushing flange 31.

The distal end of the large-diameter end portion 14 is exposed from the distal end of the reinforcing cylindrical portion 33, and is further bent outward to protrude outward from the outer diameter surface of the reinforcing cylindrical portion 33.
Is formed. A bent portion 36 facing the outer ring 3 is formed at the upper end of the pushing flange 31 to cover the end surface of the flange portion 34.

When the large-diameter end 14 of the boot 12 is mounted on the mounting portion 29, the jig is pressed against the pressing flange 31 as described above, and the large-diameter end 14 is mounted on the mounting portion 29. And the engagement rib 35 is forcibly fitted and fixed to the engagement groove 30. Thereby, the outer diameter surface of the reinforcing cylindrical portion 33 of the reinforcing member 32 is in close contact with the mounting portion 29, and the reinforcing flange 34 is pressed against the end surface of the extension portion 28. In this state, the outer peripheral surface of the pushing flange 31,
That is, the outer peripheral surface of the bent portion 36 fits within the thickness a of the extension portion 28, and the inner diameter surface of the large-diameter end portion 14 fits within the step c.

As described above, as a result of the front end face of the pushing flange 31 being set within the wall thickness a, the clearance diameter of the constant velocity universal joint 1 is determined by the outer diameter of the outer ring 3 and set within the knuckle inner diameter A (FIG. 1).

FIG. 3 shows a modified example of the reinforcing member 32. The reinforcing cylindrical portion 33 is provided with a number of slits 37 at predetermined intervals in the circumferential direction, and one end of the slit 37 is connected to the reinforcing flange 34. It is open in the opposite direction. The material (resin, rubber, or the like) of the boot 12 enters the slit 37 during the insert molding. However, the presence of the slit 37 increases the elasticity in the diameter-reducing direction, and the mounting portion 2 of the large-diameter end portion 14.
9 can be easily mounted.

FIG. 4 shows another modification of the reinforcing member 32.
In this case, the engaging piece 38 is formed by cutting and raising the reinforcing cylindrical portion 33 at a predetermined interval in the circumferential direction. The cut-and-raised engagement piece 38 is formed so that the reinforcing flange 34 side rises outward, and the entire reinforcing cylindrical portion 33 including the engagement piece 38 is embedded in the material by insert molding. An engagement groove 41 is formed between the buried portion 39 and the flange 34, and the engagement groove 41 is engaged with an engagement rib 42 formed on the outer end of the mounting portion 28.

The above-mentioned engaging piece 38 is elastically deformed inwardly at the time of mounting to facilitate the mounting of the large-diameter end portion 14, while firmly preventing the large-diameter end portion 14 from coming off after the mounting.

In the above embodiment, the reinforcing member 32 is used. However, when the boot 12 is made of a hard resin and the strength of the large-diameter end portion 14 is sufficiently large, the reinforcing member 32 is omitted. Can be. Further, even when a reinforcing member is used, only the reinforcing cylindrical portion 33 can be used.

Although the above embodiment is a wheel bearing device comprising a combination of a constant velocity universal joint 1 and a wheel bearing part 2, the constant velocity universal joint 1 separated from the wheel bearing part 2, ie, the joint body The present invention also includes a constant velocity universal joint 1 alone composed of a combination of a boot 13 and a boot 13.

[0038]

As described above, the constant velocity universal joint according to the present invention press-fits and fixes the large-diameter end of the boot to the annular mounting portion formed on the inner peripheral surface of the open end of the outer ring. Therefore, the clearance diameter of the constant velocity universal joint is not affected by the thickness of the boot and the boot band, and the diameter can be reduced as compared with the conventional case. Therefore, in the wheel bearing device incorporating the constant velocity universal joint, the work of attaching and detaching to and from the vehicle body is facilitated, and the assemblability and repairability are improved.

Further, since a boot band is not required,
The number of parts can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a state of being attached to a vehicle body according to an embodiment.

FIG. 2A is a perspective view of a reinforcing member according to the first embodiment; FIG.

FIG. 3 (a) is a perspective view of a modified example of the above-mentioned reinforcing member.

FIG. 4 (a) is a perspective view of another modification of the above-mentioned reinforcing member. FIG. 4 (b) is a partially enlarged cross-sectional view of another modification of the above.

FIG. 5A is a cross-sectional view of a conventional example mounted on a vehicle body. FIG. 5B is a partially enlarged cross-sectional view of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Constant velocity universal joint 2 Wheel bearing part 3 Outer ring 4 Inner ring 5, 5 'Track groove 6 Ball 7 Cage 8 Outer ring stem 9 Spline 11 Drive shaft 12 Boot 13 Joint main body 14 Large diameter side end part 15 Small diameter side end part 16 Boots Band 17 Outer member 18 Inner member 18a Hub ring 18b Bearing inner ring 19 Bellows portion 20a Outer rolling element 20b Inner rolling element 21 Knuckle 22 Body side flange 23 Wheel side flange 24 Spline groove 25 Nut 26 Bolt 27 Bolt 28 Extension 29 mounting part 30 engaging groove 31 pushing flange 32 reinforcing member 33 reinforcing cylindrical part 34 reinforcing flange 35 engaging rib 36 bent part 37 slit 38 engaging piece 39 buried part 41 engaging groove 42 engaging rib

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B60B 35/14 B60B 35/14 V F16C 19/38 F16C 19/38 F16D 3/224 F16D 3/224 A

Claims (11)

[Claims] 1. A large-diameter end of the boot is attached to an open end of the outer ring, comprising a joint body and boots mounted between the outer ring and the drive shaft. In the constant velocity universal joint to which the small diameter side end of the boot is attached, an annular mounting portion is provided on the inner peripheral surface of the extension provided at the open end of the outer ring, and the large diameter of the boot is provided at the mounting portion. A constant velocity universal joint having a side end press-fitted and fixed. 2. The constant velocity universal joint according to claim 1, wherein a metal cylindrical reinforcing member is integrally provided at a large-diameter end portion of the boot press-fitted into the mounting portion. 3. The method according to claim 1, wherein a pushing flange is provided on an outer diameter surface of a large-diameter end of the boot, and the flange is pressed against an end surface of the mounting portion. Speed universal joint. 4. The constant velocity universal joint according to claim 3, wherein a reinforcing flange integrated with the pushing flange is provided at one end of the reinforcing member. 5. An engaging groove extending over the entire circumference of the mounting portion, and an engaging rib provided on an outer diameter surface of a large diameter end of the boot is fitted into the engaging groove. The constant velocity universal joint according to claim 1. 6. The reinforcing member according to claim 1, wherein a plurality of slits are provided at a plurality of positions in the cylindrical portion of the reinforcing member, the slits having ends opposite to the reinforcing flanges being open to the outer end surfaces. The described constant velocity universal joint. 7. An engaging piece formed by cutting and raising the reinforcing flange side at a plurality of positions of the cylindrical part of the reinforcing member, and the cylindrical part including the engaging piece is provided inside the large-diameter end of the boot. 5. The constant velocity universal joint according to claim 4, wherein the joint is buried, an engagement groove is provided between the buried portion and the flange portion, and the engagement groove is provided on an inner diameter surface of the mounting portion. 8. The constant velocity universal joint according to claim 1, wherein said boot is made of a synthetic resin. 9. A wheel bearing device comprising a combination of a wheel bearing portion and a constant velocity universal joint, comprising: an outer member having a vehicle body mounting flange for mounting the wheel bearing portion on a vehicle body; and a wheel mounting flange for mounting a wheel. A double row rolling element is incorporated between the inner member and the inner member, the above constant velocity universal joint is constituted by the one according to any one of claims 1 to 8, and an outer ring shaft of the constant velocity universal joint is formed. A bearing device for a wheel, wherein the bearing device is coupled to an inner member of the wheel bearing portion. 10. The wheel bearing device according to claim 9, wherein the inner member is formed by a combination of a hub wheel having the wheel mounting flange and a bearing inner ring. 11. An outer diameter of an outer race of a constant velocity universal joint including a large diameter end of said boot is formed to be smaller than an inner diameter of a knuckle attached to said outer member. 4. The bearing device for a wheel according to 1.