JP2009234542A - Wheel bearing assembly - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheel bearing assembly can efficiently perform the spline coupling of a center hole of a hub spindle of a hub wheel with a center shaft of an outer ring of a constant velocity joint. <P>SOLUTION: In the wheel bearing assembly, a female spline 90 formed in the axial direction of an inner circumferential surface of a center hole 14 of the hub spindle 13 of the hub wheel 10 with a wheel being mounted thereon, and a male spline 90 formed in the axial direction of an outer circumferential surface of the center shaft 62 protruding from an end face of an outer ring 60 of a constant velocity joint 50 are spline-coupled. A non-meshing part 82 having no spline tooth is provided in an intermediate portion in the axial direction of at least one spline 80 out of the male and female splines 80, 90. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wheel bearing device in which a center hole of a hub shaft of a hub wheel to which a wheel is attached and a center shaft protruding from an end face of an outer ring of a constant velocity joint are spline-coupled.

This type of wheel bearing device is disclosed in Patent Document 1, for example.
In such a wheel bearing device, a female spline is formed in the inner peripheral surface axial direction of the center hole of the hub shaft of the hub wheel, and the outer peripheral surface axial direction of the central shaft protrudes from the end surface of the outer ring of the constant velocity joint. Is formed with a male spline corresponding to the female spline. The outer sprocket of the constant velocity joint and the hub shaft are coupled so that torque can be transmitted by meshing the female spline of the hub shaft with the male spline of the central shaft of the outer ring of the constant velocity joint. .
Japanese Patent Laid-Open No. 9-96317

By the way, in the wheel bearing device described above, one of the female spline of the hub shaft and the male spline of the central shaft of the outer ring of the constant velocity joint is formed in a spiral shape with a lead angle set in the circumferential direction. There is a case.
In this case, at one end in the axial direction of both male and female splines, the one-side facing surface of each spline tooth of these splines is in contact with no gap, and at the other axial end of both male and female splines, Torque is transmitted in a state in which the opposite surface of each spline tooth of the spline is in contact with no gap.
Further, in the axially intermediate portion of both the male and female splines, a gap is formed between the opposing surfaces of the spline teeth of these two splines, so that the portion does not fulfill the torque transmission function.

  In view of the above problems, an object of the present invention is to provide a wheel bearing device that can efficiently spline-couple the center hole of the hub shaft of the hub wheel and the center shaft of the outer ring of the constant velocity joint. .

To achieve the above object, a wheel bearing device according to a first aspect of the present invention includes a female spline formed in the axial direction of the inner peripheral surface of the center hole of the hub shaft of the hub wheel to which the wheel is attached, and a constant velocity. A wheel bearing device in which a male spline formed in the axial direction of the outer peripheral surface of the central shaft protruding from the end surface of the outer ring of the joint is spline-coupled,
One of the male and female splines has a lead angle in the circumferential direction.
Of the male and female splines, at least one of the splines is provided with a non-engagement portion having no spline teeth in an axially intermediate portion thereof.

  According to the above configuration, by providing a non-engagement portion having no spline teeth in the axially intermediate portion of at least one of the male and female splines, the spline teeth of both the male and female splines can be efficiently used. The spline can be well connected and the weight can be reduced.

The wheel bearing device according to claim 2 is the wheel bearing device according to claim 1,
In the center hole of the hub shaft, a large-diameter hole portion having a hole diameter dimension larger than the valley diameter dimension of the female spline is formed at an axially intermediate portion where the female spline is formed,
A non-meshing portion is provided by the large-diameter hole.

According to the above-described configuration, the hub shaft (hub wheel) is reduced in weight by forming the large-diameter hole portion and providing the non-meshing portion in the intermediate portion in the axial direction where the female spline of the center hole of the hub shaft is formed. be able to.
Moreover, before forming the female spline in the axial direction of the inner peripheral surface of the center hole of the hub shaft, the machining cost of the female spline can be reduced by forming a large-diameter hole at a predetermined position of the center hole of the hub shaft. Is possible.

The wheel bearing device according to claim 3 is the wheel bearing device according to claim 1 or 2,
On the central axis of the outer ring of the constant velocity joint, a small-diameter shaft portion having an outer diameter dimension smaller than the valley diameter dimension of the male spline is formed at an axially intermediate portion where the male spline is formed,
A non-meshing portion is provided by the small-diameter shaft portion.

According to the above configuration, by forming the small-diameter shaft portion and providing the non-meshing portion at the axial intermediate portion where the male spline of the central shaft of the outer ring of the constant velocity joint is formed, the central shaft of the outer ring of the constant velocity joint is provided. Weight reduction can be achieved.
Further, by forming the small-diameter shaft portion at a predetermined position of the central axis before forming the male spline in the axial direction of the outer peripheral surface of the central axis, it is possible to reduce the processing cost of the male spline.

  Next, the best mode for carrying out the present invention will be described with reference to examples.

Example 1
A first embodiment of the present invention will be described with reference to FIGS.
1 is a longitudinal sectional view showing a wheel bearing device according to Embodiment 1 of the present invention. FIG. 2 is a longitudinal sectional view showing a state where the hub wheel and the constant velocity joint are separated.

As illustrated in FIG. 1, the wheel bearing device according to the first embodiment includes a hub wheel 10, a double row angular ball bearing 20 as a rolling bearing, and a constant velocity joint 50.
The hub wheel 10 integrally has a cylindrical hub shaft 13 and a flange 11 formed on the outer peripheral surface near one end of the hub shaft 13. A plurality of hub bolts 12 for attaching a wheel (not shown) with a brake rotor (not shown) interposed therebetween are fixed to the flange 11 at a predetermined pitch and press-fitted.
A double-row angular ball bearing 20 including an outer ring 30, an inner ring 21, a plurality of balls 41 and 42 as rolling elements and cages 45 and 46 is assembled to the outer periphery of the hub shaft 13.

In the first embodiment, the hub shaft 13 is continuously formed with a large-diameter shaft portion 15 formed on the flange 11 side and a diameter that is appropriately smaller than the large-diameter shaft portion 15 and with a large-diameter shaft portion 15 and a stepped portion. The small-diameter shaft portion 16 is integrally provided. A track surface 22 corresponding to one track surface 31 of the outer ring 30 is formed on the outer peripheral surface of the large-diameter shaft portion 15.
Further, an inner ring 21 in which a raceway surface 23 corresponding to the other raceway surface 32 of the outer ring 30 is formed on the outer peripheral surface is press-fitted and fixed to the outer peripheral surface of the small-diameter shaft portion 16 of the hub shaft 13.
Further, a plurality of balls 41, 42 and a plurality of balls 41, 42 are provided between the raceways 31, 32 of the outer ring 30 and the raceways 22, 23 on the hub shaft 13 side. Are respectively assembled.
In addition, a fixing flange 35 is integrally formed on the outer peripheral surface of the outer ring 30 to be attached to a vehicle body side member (knuckle or carrier) supported by a vehicle suspension device (not shown) with a bolt.

As shown in FIG. 1, the constant velocity joint 50 uses a constant velocity joint called a well-known Zepper type or Barfield type, and includes an inner ring 52 integrally connected to one end of a drive shaft 51. The outer ring 60 includes a plurality of balls 53 disposed between the male / female wheels 52, 60, and a cage 54 that holds the plurality of balls 53.
Further, a central shaft 62 for connecting the hub wheel 10 and the constant velocity joint 50 integrally is projected at the center of the end wall portion 61 of the outer ring 60 of the constant velocity joint 50. A male screw portion 63 is formed at the tip of the central shaft 62, and a caulking groove 64 for preventing the tightening nut 65 from rotating is recessed in the male screw portion 63.

As shown in FIGS. 1 and 2, a center hole penetrating through the center of the hub shaft 13 to spline-couple the hub shaft 13 of the hub wheel 10 and the outer ring 60 of the constant velocity joint 50 so as to transmit torque. A female spline 90 is formed in the axial direction of the inner peripheral surface 14, and a male spline 80 corresponding to the female spline 90 is formed in the direction of the outer peripheral surface of the central shaft 62 of the outer ring 60 of the constant velocity joint 50.
Of these male and female splines 80, 90, one spline, for example, each spline tooth constituting the male spline 80 is helical with an appropriate lead angle set in the circumferential direction and extends in the axial direction. ing.
Moreover, each spline tooth | gear which comprises the female spline 90 as the other spline is extended in parallel with the axial direction.

Of the male and female splines 80 and 90 described above, a non-meshing portion having no spline teeth is provided at an axially intermediate portion of at least one of the splines.
In the first embodiment, an axially intermediate portion of the male spline 80 formed on the central shaft 62 of the outer ring 60 of the constant velocity joint 50 has a small diameter with an outer diameter dimension smaller than the valley diameter dimension of each spline tooth of the male spline 80. A shaft portion 82 is formed. A non-meshing portion is provided by the small diameter shaft portion 82 of the center shaft 62.

In the wheel bearing device according to the first embodiment configured as described above, when the hub shaft 13 of the hub wheel 10 and the outer ring 60 of the constant velocity joint 50 are integrally connected so as to transmit torque, first, While engaging the male spline 80 of the center shaft 62 of the outer ring 60 of the constant velocity joint 50 with the female spline 90 of the inner hole 14 of the hub shaft 13, one end side (vehicle width direction center side) to the other end side (vehicle width direction outer side). Press into the spline toward Then, the male screw portion 63 at the tip end portion of the center shaft 62 is projected to the other end side of the inner hole 14 of the hub shaft 13.
In this state, the tightening nut 65 is fastened to the male screw portion 63 of the center shaft 62. Finally, a part of the thin portion 66 at the end of the tightening nut 65 is caulked in the caulking groove 64 of the male screw portion 63 and is prevented from rotating, whereby the hub shaft 13 and the outer ring 60 of the constant velocity joint 50 are torqued. They are spline-coupled so as to be able to be transmitted and connected integrally (see FIG. 1).

  As described above, when the male and female splines 80 and 90 are spline-coupled, depending on the lead angle of each spline tooth of the male spline 80, both the splines 80 and 90 are arranged at one axial end of both male and female splines 80 and 90. , 90 one spline tooth side facing surface (tooth surface) and the large diameter surface of the male spline 80 and the tooth bottom surface of the female spline 90 are in contact with each other without any gap, and the axial direction of both the male and female splines 80, 90, etc. At the end, the other side facing surfaces (tooth surfaces) of the spline teeth of both the splines 80 and 90, the large-diameter surface of the male spline 80, and the tooth bottom surface of the female spline 90 are in contact with no gap. As a result, the hub shaft 13 and the outer ring 60 of the constant velocity joint 50 are spline-coupled so that torque can be transmitted satisfactorily.

In particular, in the first embodiment, by forming a small-diameter shaft portion 82 and providing a non-engagement portion at an axially intermediate portion where the male spline 80 of the central shaft 62 of the outer ring 60 of the constant velocity joint 50 is formed, The center shaft 62 of the outer ring 60 can be reduced in weight.
Further, by forming the small-diameter shaft portion 82 at a predetermined position of the center shaft 62 before forming the male spline 80 in the axial direction of the outer peripheral surface of the center shaft 62, it is possible to reduce the processing cost of the male spline 80. Become.

(Example 2)
Next, a second embodiment of the present invention will be described with reference to FIGS.
FIG. 3 is a longitudinal sectional view showing the wheel bearing device according to the first embodiment of the present invention. FIG. 4 is a longitudinal sectional view showing a state where the hub wheel and the constant velocity joint are separated.

As shown in FIGS. 3 and 4, in the second embodiment, the male spline 80 is continuously formed in the axial direction of the outer peripheral surface of the central shaft 62 of the outer ring 60 of the constant velocity joint 50.
On the other hand, the central hole 14 of the hub axle 13 of the hub wheel 10 has a valley diameter dimension of each spline tooth of the female spline 90 at an axially intermediate portion of the female spline 90 formed in the axial direction of the inner peripheral surface thereof. The large-diameter hole portion 92 is formed with a larger hole diameter. The large-diameter hole 92 provides a non-meshing portion.
Since the other structure of this Example 2 is comprised similarly to Example 1, the same code | symbol is attached | subjected with respect to the same component, and the description is abbreviate | omitted.

Therefore, in the wheel bearing device according to the second embodiment, a large-diameter hole portion 92 is formed in the axially intermediate portion where the female spline 90 of the center hole 14 of the hub shaft 13 is formed to provide a non-engagement portion. Thus, the hub shaft 13 can be reduced in weight.
Further, before the female spline 90 is formed in the axial direction of the inner peripheral surface of the center hole 14 of the hub shaft 13, the large-diameter hole portion 92 is formed at a predetermined position of the center hole 14 of the hub shaft 13. The processing cost can be reduced.

(Example 3)
Next, a third embodiment of the present invention will be described with reference to FIGS.
FIG. 5 is a longitudinal sectional view showing the wheel bearing device according to the first embodiment of the present invention. FIG. 6 is a longitudinal sectional view showing a state where the hub wheel and the constant velocity joint are separated.

  As shown in FIGS. 5 and 6, in the wheel bearing device according to the third embodiment, the hub shaft 113 outer peripheral surface of the hub wheel 110 and the outer peripheral surface of the end wall portion 161 of the outer ring 160 of the constant velocity joint 150 are straddled. The double-row angular ball bearing 120 including the outer ring 130, a plurality of balls 141 and 142 as rolling elements, and cages 145 and 146 is assembled.

  That is, in the third embodiment, a raceway surface 122 corresponding to one raceway surface 131 of the outer ring 130 is formed on the outer peripheral surface of the hub shaft 113 closer to the flange 111, and the end wall of the outer ring 160 of the constant velocity joint 150 is formed. A raceway surface 123 corresponding to the other raceway surface 132 of the outer ring 130 is formed on the outer peripheral surface of the portion 161. Thereby, the axial length of the wheel bearing device is shorter than that of the first embodiment.

Further, in order to spline-couple the hub shaft 113 of the hub wheel 110 and the outer ring 160 of the constant velocity joint 150 so as to be able to transmit torque, the center hole 114 extending in the center of the hub shaft 113 extends in the axial direction of the inner peripheral surface. A female spline 190 is formed, and a male spline 180 corresponding to the female spline 190 is formed in the axial direction of the outer peripheral surface of the center shaft 162 of the outer ring 160 of the constant velocity joint 150.
Of these male and female splines 180, 190, one spline, for example, each spline tooth constituting the male spline 180 has a helical shape with an appropriate lead angle set in the circumferential direction and extends in the axial direction. ing.
Moreover, each spline tooth | gear which comprises the female spline 190 as the other spline is extended in parallel with the axial direction.
Also in the third embodiment, as described in the first embodiment, each spline tooth of the male spline 180 is disposed at the axially intermediate portion of the male spline 180 formed on the center shaft 162 of the outer ring 160 of the constant velocity joint 150. A small-diameter shaft portion 182 is formed with an outer diameter dimension smaller than the valley diameter dimension. A non-meshing portion is provided by the small diameter shaft portion 182 of the central shaft 162.

  In the third embodiment, as shown in FIG. 6, a caulking cylindrical portion 167 is formed at the tip of the central shaft 162 of the outer ring 160 of the constant velocity joint 150. Then, after the male spline 180 of the center shaft 162 of the outer ring 160 of the constant velocity joint 150 is spline-fitted while meshing with the female spline 190 of the inner hole 114 of the hub shaft 113 of the hub wheel 110, the cylinder at the tip of the center shaft 62 is inserted. The portion 167 is caulked radially outward along the outer end surface of the hub shaft 113 to form a caulking portion 168, so that the hub shaft 113 and the outer ring 160 of the constant velocity joint 150 are spline-coupled so that torque can be transmitted. So that they are connected together.

The wheel bearing device according to the third embodiment is configured as described above.
Therefore, by forming a small diameter shaft portion 82 and providing a non-meshing portion at an axially intermediate portion where the male spline 180 of the central shaft 162 of the outer ring 160 of the constant velocity joint 150 is formed, the central shaft 162 of the outer ring 160 is provided. Weight reduction can be achieved.
Further, by forming the small-diameter shaft portion 82 at a predetermined position of the center shaft 162 before forming the male spline 180 in the outer peripheral surface axial direction of the center shaft 162, it is possible to reduce the processing cost of the male spline 180. Become.
Further, in the third embodiment, as described in the second embodiment, a large-diameter hole portion is formed in the intermediate portion in the axial direction where the female spline 190 of the center hole 114 of the hub shaft 113 of the hub wheel 110 is formed. Even in the case where the non-meshing portion is provided, the same effect can be obtained.

In addition, this invention is not limited to the said Examples 1-3.
For example, in the first to third embodiments, the case where a double-row angular ball bearing is employed as the rolling bearing has been illustrated, but the present invention can also be implemented using a double-row tapered roller bearing in addition to the angular ball bearing. It is.

It is a longitudinal cross-sectional view which shows the wheel bearing apparatus which concerns on Example 1 of this invention. It is a longitudinal section showing the state where a hub wheel and a constant velocity joint were separated similarly. It is a longitudinal cross-sectional view which shows the wheel bearing apparatus which concerns on Example 2 of this invention. It is a longitudinal section showing the state where a hub wheel and a constant velocity joint were separated similarly. It is a longitudinal cross-sectional view which shows the wheel bearing apparatus which concerns on Example 3 of this invention. It is a longitudinal section showing the state where a hub wheel and a constant velocity joint were separated similarly.

Explanation of symbols

10, 110 Hub wheel 11 Flange 13, 113 Hub shaft 14, 114 Center hole 20, 120 Angular contact ball bearing (rolling bearing)
50, 150 Constant velocity joint 60, 160 Outer ring 61, 161 End wall 62, 162 Center shaft 80, 180 Male spline 82, 182 Small diameter shaft (non-meshing part)
90, 190 Female spline 92 Large diameter hole (non-meshing part)

Claims (3)

A female spline formed in the axial direction of the inner peripheral surface of the center hole of the hub shaft of the hub wheel to which the wheel is attached, and a male spline formed in the outer peripheral surface axial direction of the central axis protruding from the end surface of the outer ring of the constant velocity joint. Is a spline-coupled wheel bearing device,
One of the male and female splines has a lead angle in the circumferential direction.
A wheel bearing device, wherein a non-meshing portion having no spline teeth is provided at an axially intermediate portion of at least one of the male and female splines. The wheel bearing device according to claim 1,
In the center hole of the hub shaft, a large-diameter hole portion having a hole diameter dimension larger than the valley diameter dimension of the female spline is formed at an axially intermediate portion where the female spline is formed,
A wheel bearing device, wherein a non-meshing portion is provided by the large-diameter hole portion. The wheel bearing device according to claim 1 or 2,
On the central axis of the outer ring of the constant velocity joint, a small-diameter shaft portion having an outer diameter dimension smaller than the valley diameter dimension of the male spline is formed at an axially intermediate portion where the male spline is formed,
A wheel bearing device, wherein a non-meshing portion is provided by the small-diameter shaft portion.

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