JP2009083813A - Wheel support apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce bearing pressure and shearing stress of a tooth surface, by increasing the contact area of mutual tooth surfaces of both-side face splines by that extent, by reducing the area of a noncontact part of the both-side face splines on the hub wheel side and the constant velocity joint side. <P>SOLUTION: The both-side face splines 80 and 90 connecting both of these so that torque can be transmitted, are formed on an end surface of a hub shaft 13 of a hub wheel 10 and an end surface of an outer ring 60 of a constant velocity joint 50. Among the both-side face splines 80 and 90, a bottom surface 82 of at least one-side face spline 80 is formed in an angle shape with an inner diameter side inclined face 84 deepening toward the inner diameter end from this top part 83 and an outer diameter side inclined face 85 deepening toward the outer diameter end from the top part 83, with a basic circle surface positioned substantially in the middle between its inner diameter circle and an outer diameter circle as the top part 83. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a wheel support device in which a hub shaft of a hub wheel to which a wheel is attached and an outer ring of a constant velocity joint are connected so as to be able to transmit torque.

This type of wheel support device is disclosed in Patent Document 1, for example.
In this case, as shown in FIG. 7, double row angular balls as rolling bearings having an inner ring 121, an outer ring 130, and balls (rolling elements) 141, 142 on the outer peripheral surface of the hub shaft 113 of the hub wheel 110. A bearing 120 is assembled.
On the other hand, a connecting shaft portion 163 extends integrally from the end surface of the side wall portion 161 of the outer ring 160 of the constant velocity joint 150 to which the end portion of the drive shaft 151 is connected.
Further, an inner spline 114 is formed on the inner peripheral surface of the inner hole of the hub shaft 113 of the hub wheel 110, and an outer spline 164 that meshes with the inner spline 114 is formed on the outer peripheral surface of the connecting shaft portion 163. .
The connecting shaft portion 163 is fitted into the inner hole of the hub shaft 113 of the hub wheel 110 while the inner and outer splines 114 and 164 are engaged with each other, and the male screw portion 165 protruding from the tip of the connecting shaft portion 163. By tightening the tightening nut 166, the hub wheel 110 and the constant velocity joint 150 are coupled so as to be able to transmit torque.
JP 2002-114004 A

By the way, in the wheel support device disclosed in Patent Document 1, the torque of the outer ring 160 of the constant velocity joint 150 that rotates in the same direction as the drive shaft 151 is, for example, during traveling of the vehicle, the inner and outer splines 114, 164. Is transmitted to the hub wheel 110 and the wheel is driven to rotate.
At this time, relative slip (twist) is caused between the contact surfaces of the end surface of the side wall 161 of the outer ring 160 of the constant velocity joint 150 and the end surface of the hub shaft 113 of the hub wheel 110 (end surface of the caulking portion 117). Slipping), and abnormal noise may occur.
As shown in FIG. 8, in order to prevent the occurrence of abnormal noise caused by relative slip between the end surface of the side wall portion 161 of the outer ring 160 of the constant velocity joint 150 and the end surface of the hub shaft 113 of the hub wheel 110, as shown in FIG. Both side face splines 280 and 290 are formed on the end face of the caulking portion 217 of the hub shaft 213 and the end face of the side wall portion 261 of the outer ring 260 of the constant velocity joint 250 that is abutted against the end face. It is proposed by the same applicant that the hub shaft 213 of the hub wheel 210 and the outer ring 260 of the constant velocity joint 250 are connected to each other so that torque can be transmitted by meshing 290 with each other.
When the side face splines 280 and 290 are formed by forging on the end face of the caulking portion 217 of the hub shaft 213 and the end face of the side wall portion 261 of the outer ring 260 of the constant velocity joint 250, the bottom surfaces 282 and 292 of the side face splines 280 and 290 are The inclined surface gradually becomes deeper from the inner diameter end toward the outer diameter end.
For this reason, the engagement of both side face splines 280, 290 is limited on the inner diameter side of the tooth bottom surfaces 282, 292 of both side face splines 280, 290. As a result, a non-contact portion S is formed in which the spline teeth are not brought into contact with the outer diameter side portion where the bottom surfaces 282, 292 of the side face splines 280, 290 are deep. As a result, the surface pressure and the shear stress of the tooth surface of the spline teeth at the contact portions of the both side face splines 280 and 290 are expected to increase, and the durability is expected to be hindered.

  In view of the above problems, an object of the present invention is to reduce the area of the non-contact portion of both side face splines on the hub wheel side and the constant velocity joint side, and to this extent, the mutual tooth surfaces of both side face splines are reduced. It is an object of the present invention to provide a wheel support device that can increase the contact area to reduce the tooth surface pressure and shear stress.

In order to achieve the above object, a wheel support device according to claim 1 of the present invention is a wheel support device in which a hub shaft of a hub wheel to which a wheel is attached and an outer ring of a constant velocity joint are connected so as to be able to transmit torque. There,
The hub shaft of the hub wheel and the outer ring of the constant velocity joint are connected to each other so that torque can be transmitted between the end surface of the hub shaft and the end surface of the outer ring of the constant velocity joint abutted on the end surface. Both side face splines are formed,
Of the two side face splines, the tooth bottom surface of at least one of the side face splines has a top on a basic circle located approximately in the middle of the inner diameter circle and the outer diameter circle, and gradually increases from the top to the inner diameter end. The inner diameter side inclined surface which becomes deeper and the outer diameter side inclined surface which gradually becomes deeper from the top toward the outer diameter end are formed in a mountain shape.

According to the above configuration, the torque on the constant velocity joint side is transmitted to the hub wheel by the engagement of both side face splines of the end surface of the outer ring of the constant velocity joint and the end surface of the hub shaft when the vehicle is running, etc., and the wheel rotates. Driven.
In this way, the torque on the constant velocity joint side can be satisfactorily transmitted to the hub wheel side by the meshing of both side face splines, so unlike the conventional case, the end surface of the outer ring of the constant velocity joint and the hub axle of the hub wheel The occurrence of abnormal noise can be prevented by suppressing the relative slip between the end face of each of the two.
In addition, since the tooth bottom surface of at least one side face spline of both side face splines has an inner diameter side inclined surface and an outer diameter side inclined surface, the tooth bottom surface is formed from the inner diameter end. The area of the non-contact portion of both side face splines can be reduced as compared with the case where the inclined surface gradually becomes deeper toward the outer diameter end.
That is, it is possible to prevent the meshing from being restricted on the inner diameter side of the tooth bottom surface of the side face spline, and thereby to reduce the area of the non-contact portion of both side face splines.
In addition, the contact area between the tooth surfaces of both side face splines can be increased by reducing the area of the non-contact portion of both side face splines, and the surface pressure and shear stress of the tooth faces can be reduced to improve durability. Can be improved.

  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 side sectional view showing a wheel support device according to Embodiment 1 of the present invention. FIG. 2 is an enlarged perspective view showing a part of the side face spline on the end surface of the hub shaft of the hub wheel. FIG. 3 is an enlarged sectional view showing a state where both side face splines are separated. FIG. 4 is an enlarged cross-sectional view showing a state in which both side face splines are engaged with each other.

As shown in FIG. 1, the wheel support 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.

That is, in the first embodiment, the hub shaft 13 has a large-diameter shaft portion 15 formed on the flange 11 side, and has a suitably smaller diameter than the large-diameter shaft portion 15 and continuously with the large-diameter shaft portion 15 and a stepped portion. The formed 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, after the inner ring 21 in which the raceway surface 23 corresponding to the other raceway surface 32 of the outer ring 30 is formed on the outer peripheral surface is fitted into the outer peripheral surface of the small-diameter shaft portion 16 of the hub shaft 13, the tip of the small-diameter shaft portion 16. The inner ring 21 is fixed between the stepped portion and the caulking portion 17 by caulking the portion to form the caulking portion 17.
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 inner and outer rings 52, 60, and a cage 54 that holds the plurality of balls 53.
Further, a connecting bolt 70 for connecting the hub wheel 10 and the constant velocity joint 50 integrally is projected at the center of the side wall 61 of the outer ring 60 of the constant velocity joint 50.

In the first embodiment, the connecting bolt 70 has a head portion 71 and a shaft portion 72 that are separate from the outer ring 60 of the constant velocity joint 50, and is provided at the center of the side wall portion 61 of the outer ring 60 of the constant velocity joint 50. Has a through hole 63.
Then, the shaft portion 72 of the connecting bolt 70 is fitted and inserted from the inner opening portion of the through hole 63 of the outer ring 60 of the constant velocity joint 50, and the shaft portion 72 reaches a position where the lower surface of the head portion 71 contacts the inner surface of the side wall portion 61. The shaft portion 72 of the connecting bolt 70 is protruded and fixed from the side wall portion 61 of the outer ring 60 of the constant velocity joint 50 by press-fitting the large diameter portion 72a of the base portion. A male screw portion 73 is formed at the tip of the shaft portion 72 of the connecting bolt 70, and a caulking groove 74 for preventing the tightening nut 75 from rotating is recessed in the male screw portion 73.

  As shown in FIGS. 1 and 2, the end surface of the hub shaft 13 of the hub wheel 10 (in this embodiment 1, the end surface of the caulking portion 17 of the hub shaft 13) and the outer ring 60 of the constant velocity joint 50 abutted against the end surface. Both side face splines 80 and 90 are formed on the end surface of the side wall portion 61 so as to mesh with each other so as to connect the hub shaft 13 and the outer ring 60 of the constant velocity joint 50 so that torque can be transmitted.

As shown in FIGS. 2 and 3, the bottom surface 82 of the spline tooth 81 of the side face spline 80 on the end face of the caulking portion 17 of the hub shaft 13 includes an inner diameter circle (diameter dimension A) of the caulking portion 17 and an outer diameter circle ( A base circle (diameter dimension C) positioned approximately in the middle of the diameter dimension B) is a top portion 83, an inner diameter side inclined surface 84 that gradually becomes deeper from the top portion 83 toward the inner diameter end, and an outer diameter end from the top portion 83. It has an outer diameter side inclined surface 85 that gradually becomes deeper toward the surface, and is formed in a mountain shape.
In the first embodiment, the center axis of the caulking portion 17 is L, and a reference line that is perpendicular to the center axis L and passes through the tip surface 86 of the spline tooth 81 of the side face spline 80 is H, and the center axis L The angle from the intersection O1 is defined as O1 when the intersection between the reference line H and the reference line H is O1, and the intersection between the reference line H and the circle having the diameter D that is twice the diameter of the base circle (diameter C) is O2. An outer diameter side inclined surface 85 is formed on a conical surface having θ1.
Further, an intersection of the conical surface having an angle θ1 from the intersection O1 and the basic circle (diameter dimension C) is defined as a top portion 83. Furthermore, an inner diameter side inclined surface 84 is formed on a conical surface having the same angle θ2 as the angle θ1 from the intersection point O2.

On the other hand, the bottom surface 92 of the spline teeth 91 of the side face spline 90 on the end surface of the side wall portion 61 of the outer ring 60 of the constant velocity joint 50 also extends from the top 93 to the inner diameter end in the same manner as the side face spline 80 on the hub shaft 13 side. The inner diameter side inclined surface 94 that gradually becomes deeper toward the outer diameter side and the outer diameter side inclined surface 95 that gradually becomes deeper from the top portion 93 toward the outer diameter end are formed in a mountain shape.
The hub wheel 10 and the constant velocity joint 50 are integrally connected so as to transmit torque as follows.
That is, first, the shaft portion 72 of the connecting bolt 70 protruding from the end surface of the side wall portion 61 of the outer ring 60 of the constant velocity joint 50 is moved from one end side (vehicle width direction center side) of the inner hole 14 of the hub shaft 13 of the hub wheel 10. Insert it toward the other end (outside in the vehicle width direction).
Thereafter, the male screw portion 73 at the distal end portion of the shaft portion 72 of the connecting bolt 70 is engaged with the side face spline 80 on the end surface of the hub shaft 13 and the side face spline 90 on the end surface of the side wall portion 61 of the outer ring 60 of the constant velocity joint 50. A tightening nut 75 is tightened to the male screw portion 65 in a state of protruding to the other end side of the inner hole 14 of the hub shaft 13. Here, a part of the thin portion 76 at the end of the tightening nut 75 is caulked in the caulking groove 74 of the male screw portion 73 and is prevented from rotating, so that the hub wheel 10 and the constant velocity joint 50 can transmit torque. They are connected together (see FIG. 1).

The wheel support device according to the first embodiment is configured as described above.
Accordingly, during traveling of the vehicle, the torque of the drive shaft 51 is sequentially transmitted to the inner ring 52, the plurality of balls 53, and the outer ring 60 of the constant velocity joint 50, and the outer ring 60 of the constant velocity joint rotates in the same direction as the drive shaft 51. Is done.
The torque transmitted to the constant velocity joint 50 is transmitted to the hub wheel 10 by the engagement of the side face splines 80 and 90 between the end surface of the hub shaft 13 and the end surface of the outer ring 60 of the constant velocity joint 50, and the wheel is driven to rotate. .

As described above, the torque on the constant velocity joint 50 side can be satisfactorily transmitted to the hub wheel 10 side by the meshing of both side face splines 80 and 90.
For this reason, unlike the conventional case, relative slip between the end surface of the outer ring 60 of the constant velocity joint 50 and the end surface of the hub axle 13 of the hub wheel 10 (end surface of the caulking portion 17) can be satisfactorily suppressed. . As a result, it is possible to prevent the generation of abnormal noise that causes a relative slip between the end surface of the outer ring 60 of the constant velocity joint 50 and the end surface of the hub shaft 13 of the hub wheel 10.

Further, the tooth bottom surfaces 82 and 92 of both side face splines 80 and 90 are formed in a mountain shape having inner diameter side inclined surfaces 84 and 94 and outer diameter side inclined surfaces 85 and 95. For this reason, the area of the non-contact portion of both side face splines 80 and 90 is reduced as compared with the case where the bottom surfaces of both side face splines are formed to be inclined surfaces that gradually become deeper from the inner diameter end toward the outer diameter end. be able to.
That is, by providing the inner diameter side inclined surfaces 84, 94 on the bottom surfaces 82, 92 of both side face splines 80, 90, the engagement of both side face splines 80, 90 is limited on the inner diameter side of the bottom surfaces 82, 92. Can be suppressed. As a result, the area of the non-contact portion of both side face splines 80 and 90 can be reduced.
In addition, the contact area between the tooth surfaces can be increased by reducing the area of the non-contact portions of both side face splines 80 and 90, and the surface pressure and shear stress of the tooth surfaces can be reduced to improve durability. Can be achieved.

(Example 2)
Next, a second embodiment of the present invention will be described with reference to FIGS.
FIG. 5 is an enlarged sectional view showing a state where both side face splines of the wheel support device according to Embodiment 2 of the present invention are separated. FIG. 6 is an enlarged sectional view showing a state in which both side face splines are engaged with each other.
As shown in FIGS. 5 and 6, in the second embodiment, the tip surface 96 of the spline tooth 91 (or 81) of one side face spline 90 (or 80) of both side face splines 80 and 90. (Or 86) is formed in a shape corresponding to the tooth bottom surface 82 (or 92) of the other side face spline 80 (or 90).
That is, as shown in FIG. 5, the tip surface 96 of the spline tooth 91 of the side face spline 90 on the end face of the outer ring 60 of the constant velocity joint 50 is the bottom surface 82 of the spline tooth 81 of the side face spline 80 on the end face of the hub shaft 13. The portion facing the top portion 83 is a trough portion 97, and the inner diameter side tip surface 98 gradually increases from the trough portion 97 toward the inner diameter end, and gradually increases from the trough portion 97 toward the outer diameter end. The outer diameter side tooth tip surface 99 is formed into a V shape.
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.

  In the wheel support device according to the second embodiment configured as described above, the tooth tip surface 96 of the spline tooth 91 of one side face spline 90 corresponds to the chevron of the tooth bottom surface 82 of the other side face spline 80. By forming in a shape, the area of the non-contact portion of both side face splines 80 and 90 can be further reduced, and the contact area between the tooth surfaces can be increased by this amount. As a result, the effect of reducing the tooth surface pressure and shear stress is great.

The present invention is not limited to the first and second embodiments.
For example, in the first and second embodiments, the tooth bottom surfaces 82 and 92 of both the side face splines 80 and 90 include the inner diameter side inclined surfaces 84 and 94 and the outer diameter side inclined surfaces 85 and 95, respectively. However, the bottom surface 82 of the spline tooth 81 of one side face spline 80 (or 90) has an inner diameter side inclined surface 84 and an outer diameter side inclined surface 85 to form a mountain shape. Even when it is formed, the present invention can be implemented.
In the first embodiment, the case where the connecting bolt 70 separate from the outer ring 60 is fixed to the through hole 63 of the side wall 61 of the outer ring 60 of the constant velocity joint 50 by press-fitting is illustrated. The present invention can be implemented even when the connecting bolt protrudes integrally from the side wall portion 61.
Further, as the rolling bearing on the hub wheel side, the present invention can be implemented by using a double row tapered roller bearing in addition to the double row angular ball bearing 20.

It is a sectional side view which shows the wheel support apparatus which concerns on Example 1 of this invention. It is a perspective view which expands and shows a part of side face spline of the hub axial end surface of a hub wheel similarly. Similarly, it is sectional drawing which expands and shows the state which both the side face splines isolate | separated. Similarly, it is sectional drawing which expands and shows the state in which both side face splines were meshed. It is sectional drawing which expands and shows the state which both the side face splines of the wheel support apparatus which concerns on Example 2 of this invention isolate | separated. Similarly, it is sectional drawing which expands and shows the state in which both side face splines were meshed. It is a sectional side view which shows the state by which the connection shaft part of the constant velocity joint was spline-fitted in the hub axle inner hole of the hub wheel of the conventional wheel support apparatus. It is sectional drawing which shows the state in which the side face spline of the outer ring | wheel end surface of the constant velocity joint was meshed | engaged with the side face spline of the hub axle end surface of the hub wheel of a reference example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Hub wheel 11 Flange 13 Hub axle 17 Caulking part 20 Double row angular contact ball bearing (rolling bearing)
50 Constant velocity joint 60 Outer ring 80, 90 Side face spline 81, 91 Spline teeth 82, 92 Bottom surface 83, 93 Top portion 84, 94 Inner diameter side inclined surface 85, 95 Outer diameter side inclined surface

Claims (1)

A wheel support device in which a hub shaft of a hub wheel to which a wheel is attached and an outer ring of a constant velocity joint are connected so as to be able to transmit torque,
The hub shaft of the hub wheel and the outer ring of the constant velocity joint are connected to each other so that torque can be transmitted between the end surface of the hub shaft and the end surface of the outer ring of the constant velocity joint abutted on the end surface. Both side face splines are formed,
Of the two side face splines, the tooth bottom surface of at least one of the side face splines has a top on a basic circle located approximately in the middle of the inner diameter circle and the outer diameter circle, and gradually increases from the top to the inner diameter end. A wheel support device, characterized by having an inner diameter side inclined surface that becomes deeper and an outer diameter side inclined surface that gradually becomes deeper from the top toward the outer diameter end, and is formed in a mountain shape.

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