JP2006105343A - Bearing device for wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device for a wheel capable of preventing creep on a fitting portion of a hub ring and an inner ring, and retaining the inner ring with a simple constitution at low cost. <P>SOLUTION: An external member 1 having double row rolling faces 4 on its inner periphery, and an internal member 2 having rolling faces opposite to the rolling faces 4 on its outer periphery are mounted, and double row rolling elements 3 are mounted respectively between the rolling faces 4, 5 opposite to each other. The internal member 2 is composed of the hub ring 2A having a flange 2a for mounting the wheel, and the inner ring 2B fitted to an outer periphery of the hub ring 2A. A locking recessed portion 10 is formed on a part in the circumferential direction, of an inside diameter face of the inner ring 2B corresponding to an inboard side end of the hub ring 2A. A locking projection portion 11 engaged in the locking recessed portion 10 of the inner ring B by plastic flow, is formed on the hub ring 2A by contracting or expanding a diameter of the fitting portion of the hub ring 2A and the inner ring 2B. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a wheel bearing device that supports wheels of a vehicle such as an automobile.

  Conventionally, as a wheel bearing device, there is one in which a rotating side wheel is constituted by a hub wheel and an inner ring press-fitted into the outer periphery thereof. In this type of wheel bearing device, the inner ring is simply fixed to the inner ring side end of the hub ring by caulking to the outer diameter side, and this caulking portion is pressed against the width of the inner ring in the axial direction. There are some that fix the inner ring to the hub ring with preload applied.

  However, in situations where heavy loads occur, such as when the vehicle is turning, the love wheel that is press-fitted and fixed to the hub wheel may creep, resulting in a large bearing clearance and a short life.

Then, what is shown in FIG. 7 is proposed as a wheel bearing apparatus which eliminates such a malfunction (patent document 1). In this wheel bearing device, an uneven portion 23 is formed on one or both of the fitting surfaces of the hub wheel 22A and the inner ring 22B, both of the hub wheel 22A and the inner ring 22B fitted to the outer periphery thereof. The fitting portion is plastically bonded by expanding or reducing the diameter. As the concavo-convex part 23, a spiral thing like a screw, an iris knurl, a serration, etc. are mentioned.
JP 2001-18604 A

  However, the configuration disclosed in Patent Document 1 has a problem in that it takes time to process the concave and convex portion 23 that plastically connects the hub wheel 22A and the inner ring 22B, resulting in an increase in cost.

  An object of the present invention is to provide a wheel bearing device capable of preventing creep at a fitting portion between a hub ring and an inner ring and preventing the inner ring from coming off with a simple configuration.

The wheel bearing device of the present invention includes an outer member having a double-row rolling surface on the inner periphery, an inner member having a rolling surface facing the respective rolling surfaces on the outer periphery, and the opposing rolling A plurality of rolling elements interposed between the surfaces, the inner member comprising a hub wheel having a wheel mounting flange and an inner ring fitted to the outer periphery of the hub wheel, A wheel bearing device which is rotatably supported and has the following configuration. That is, a locking recess is provided in a part in the circumferential direction of the inner diameter surface of the inner ring corresponding to the inboard side end of the hub ring, and the hub is reduced or expanded by the fitting portion of the hub ring and the inner ring. The ring is provided with a locking projection that is engaged by plastic flow in the locking recess of the inner ring. The locking recess may be one place in the circumferential direction, but is preferably a plurality of places.
According to this configuration, since the locking recess is provided in a part of the circumferential direction and the locking projections of the hub wheel are engaged, the inner ring is engaged by the engagement of the locking recess and the locking projection. Rotation is prevented, and the occurrence of creep is prevented. Further, the engagement between the locking recess and the locking projection prevents the inner ring from coming off. The locking recess may be a simple shape provided in a part of the inner ring in the circumferential direction, and the locking protrusion is formed by plastic flow due to the diameter expansion of the fitting portion between the hub ring and the inner ring. These locking recesses and locking projections can be easily formed and assembled, and can be formed at low cost.

The locking recess may have a groove shape extending in the axial direction from the end face of the inner ring on the inboard side. In this case, the locking recess functions to prevent rotation by the same action as the keyway.
Further, the locking recess is formed at a corner portion between an end face on the inboard side of the inner ring and an inner diameter, and the bottom shape of the locking recess is an arc shape in a cross section including the inner ring central axis. May be. When the locking recess is formed in an arc shape in this way, the processing of the locking recess is simple, and the cost for the processing can be further reduced.

In this invention, a step portion having a larger diameter than the inner diameter surface is provided on the entire circumference of the inner diameter surface of the inner ring corresponding to the inboard end side of the hub wheel, and the step is provided on a part of the inner peripheral surface of the step portion. A locking recess is provided, and the hub ring and the inner ring are engaged with each other by plastic flow and engagement with the hub ring in the stepped portion and the locking recess, respectively, due to the reduced or expanded diameter of the fitting portion between the hub ring and the inner ring. A stop portion and the locking projection may be provided.
In this way, when the stepped portion over the entire circumference and the locking stepped portion that engages with the stepped portion are provided, it is possible to further strengthen the proof strength of the inner ring against the hub wheel.

  In this invention, the inner member may be one in which the rolling surfaces of the rows are formed on the hub wheel and the inner ring. That is, it may be a third generation type wheel bearing device. In the case of such a wheel bearing device in which only the rolling surface of one row is formed by the inner ring, engagement between a part of the locking recesses in the circumferential direction and a locking protrusion of the hub wheel engaged therewith With such a simple configuration, it is easy to sufficiently obtain the necessary effects of preventing creep and preventing the inner ring from falling off.

In this invention, the locking projection is formed by caulking to expand the inboard side end of the hub wheel, and the rolling surface of the hub wheel is a hardened surface-hardened surface, The inboard side end to be caulked may be a non-heat treated part, and the entire inner ring from the surface to the core part may be hardened by a quenching process.
The rolling surface of the hub wheel is preferably hardened as a surface-hardened surface from the viewpoint of improving the rolling life, but the portion where the caulking process is performed is made easy for the caulking process. It is preferable to use a non-heat treated part as it is. The inner ring is a small part, has a rolling surface, and the inner diameter surface is fitted to the hub ring, so that the entire surface from the surface to the core is hardened by quenching. It is preferable in terms of life and wear resistance of the fitting surface.

  The wheel bearing device of the present invention is provided with a locking recess in a part of the inner surface of the inner ring corresponding to the inboard side end of the hub ring in the circumferential direction, and the reduced diameter of the fitting part between the hub ring and the inner ring or By expanding the diameter, the hub ring is provided with a locking protrusion that is plastically flowed into the locking recess of the inner ring to prevent creep at the fitting portion between the hub ring and the inner ring. The inner ring can be prevented from coming off with a simple configuration, and the processing for preventing the inner ring can be performed at a low cost.

A first embodiment of the present invention will be described with reference to FIGS. The wheel bearing device of this embodiment is an example applied to a wheel bearing for driving wheel support, which is a third generation inner ring rotating type. In the present invention, the side closer to the outer side in the vehicle width direction of the vehicle when attached to the vehicle is referred to as the outboard side, and the side closer to the center of the vehicle is referred to as the inboard side. In FIG. 1, the left side is the outboard side and the right side is the inboard side.
In FIG. 1, the wheel bearing device includes an outer member 1 having double-row rolling surfaces 4 on the inner periphery, and an inner member 2 having rolling surfaces 5 facing the rolling surfaces 4 on the outer periphery. And the double row rolling elements 3 interposed between the double row rolling surfaces 4 and 5. This bearing device is a double-row angular contact ball bearing. Each of the rolling surfaces 4 and 5 has an arcuate cross section, and each of the rolling surfaces 4 and 5 is formed so that the contact angle is aligned with the back surface. ing. The rolling elements 3 are formed of balls and are held by the cage 6 for each row. Both ends of the annular space formed between the outer member 1 and the inner member 2 are sealed by contact type seals 7 and 8, respectively.

  The outer member 1 is a member on the fixed side, and has a vehicle body mounting flange 1a for fixing to a knuckle (not shown) of the suspension device of the vehicle body on the outer periphery, and the whole is an integral member. ing. The vehicle body mounting flange 1a is fastened to the knuckle with a bolt (not shown).

The inner member 2 is a member on the rotation side, and includes a hub wheel 2A having a wheel mounting flange 2a on the outer periphery, and an inner ring 2B fitted to the outer periphery of the end portion on the inboard side of the hub wheel 2A. Consists of. The rolling surfaces 5 of each row are formed on the hub wheel 2A and the inner ring 2B. An outer ring (not shown) of a constant velocity joint, which is a joint member of a shaft joint, is connected to the hub wheel 2A.
The hub wheel 2 </ b> A has an inner ring fitting surface 9 constituting a step portion on the outer periphery of the end portion on the inboard side, and the inner ring 2 </ b> B is fitted to the inner ring fitting surface 9. The hub 2A of the hub wheel 2A has a hub bolt 18 that passes through the bolt insertion hole 17 and a hub nut (not shown) that is screwed into the hub bolt 18 so that a brake rotor and a wheel (not shown) of the disc brake device are shown. ) And are attached in layers.

  The rolling surface 5 of the hub wheel 2A is a hardened surface-cured surface, and the inboard side end, which is a portion for performing a caulking process described later, is a non-heat-treated portion. The inner ring fitting surface 9 of the hub wheel 2 </ b> A has the inboard side portion as the non-heat-treated portion, but the outboard side portion is a surface-hardened surface following the rolling surface 5. The entire inner ring 2B is hardened by a quenching process from the surface to the core.

Locking recesses 10 are provided in a part of the inner diameter surface of the inner ring 2 </ b> B in the circumferential direction (here, three locations separated from each other by 120 ° in circumferential angle) as shown in FIG. 2. The locking recess 10 has a key groove shape extending in the axial direction from the end face on the inboard side of the inner ring 2B.
Locking protrusions 11 that engage with the respective locking recesses 10 are provided on the hub wheel 2A as shown in FIG. The locking projection 11 is formed by caulking to increase the diameter of the inboard side end of the hub wheel 2A while the inner ring 2B is fitted to the hub wheel 2A. That is, due to the diameter expansion of the hub wheel 2A, the material of the hub wheel 2A plastically flows into the locking recess 10 to form the locking protrusion 11. At this time, the locking projection 11 is formed to engage with the locking recess 10.
The locking projection 11 may be formed by reducing or increasing the diameter of the fitting portion between the hub wheel 2A and the inner ring 2B, and may be formed by reducing the diameter of the inner ring 2B. In order to ensure the accuracy of the rolling surface 5 or the like, it is easier to increase the diameter of the hub wheel 2A.

  According to the wheel bearing device, since the locking recess 10 is provided in a part of the inner ring 2B in the circumferential direction and the locking protrusion 11 of the hub wheel 2A is engaged, the locking recess 10 and the locking protrusion The rotation of the inner ring 2B is prevented by the circumferential engagement with 11 and the occurrence of creep is prevented. Further, the engagement between the locking recess 10 and the locking projection 11 in the axial direction prevents the inner ring 2B from coming off. The locking recess 10 has a simple key groove shape provided in a part of the inner ring 2B in the circumferential direction, and the locking protrusion 11 is an expansion of the fitting portion between the hub ring 2A and the inner ring 2B. Since it is formed by plastic flow depending on the diameter, it is easy to form and assemble the locking recess 10 and the locking projection 11 and can be formed at low cost. For example, the processing cost is lower than that in the case of processing uneven portions such as iris knurls and serrations as in the conventional example.

  In addition, the rolling surface 5 of the hub wheel 2A is a hardened surface-hardened surface, the inboard side end for caulking for forming the locking protrusion 11 is a non-heat treated portion, and the inner ring 2B is a core from the surface. Since the entire part is hardened by the quenching process, the rolling life of each rolling surface 5 can be secured without hindering the caulking of the hub wheel 2A.

FIG. 3 shows another example of the locking recess 10 of the inner ring 2B in the first embodiment. The locking recess 10 of this example is formed at the corner between the end face on the inboard side of the inner ring 2B and the inner diameter surface, and the bottom shape of the locking recess 10 is a single circle in the cross section including the inner ring central axis. It is an arc shape.
By forming the locking recess 10 in such an arc shape, the locking recess 10 can be easily processed, and the cost for the processing can be reduced.

  4 and 5 show another embodiment of the present invention. In this embodiment, in the wheel bearing device of the first embodiment shown in FIG. 1, a step portion 12 having a larger diameter than the inner diameter surface is provided on the entire circumference of the inner diameter surface of the inner ring 2B as shown in FIG. In addition, a locking recess 10 similar to that in the case of FIG. 2 is provided at a part of the inner peripheral surface of the stepped portion 12 (here, three locations separated from each other by 120 ° in circumferential angle). The diameter of the fitting portion between the hub wheel 2A and the inner ring 2B is increased as in the case of the first embodiment. Due to this diameter expansion, as shown in FIG. 4, the locking step 13 and the locking projection 11 which are engaged by plastic flow in the step 12 and the locking recess 10 of the inner ring 2B are respectively attached to the hub wheel 2A. Provided. Other configurations are the same as those in the first embodiment.

  In this embodiment, in addition to the partial locking recess 10 in the inner ring 2B, a step 12 over the entire inner circumference of the inner ring 2B is provided, and the locking step 13 of the hub ring 2A is engaged over the entire circumference. For this reason, it is possible to further strengthen the pull-out resistance of the inner ring 2B with respect to the hub ring 2A.

FIG. 6 shows still another embodiment of the present invention, which is applied to the second generation type.
In this wheel bearing device, as in the first embodiment, the inner member 2 is composed of a hub wheel 2A and an inner ring 2B fitted to the outer diameter surface of the hub wheel 2A. Two inner rings 2B1 and 2B2 are arranged in the direction, and each row of rolling surfaces 5 is formed on each inner ring 2B1 and 2B2. The locking recess 10 in the first embodiment is formed on the inner ring 2B2 corresponding to the inboard side end of the hub wheel 2A here. Other configurations are the same as those in the first embodiment.

It is sectional drawing of the wheel bearing apparatus concerning 1st Embodiment of this invention. (A) is sectional drawing of the inner ring | wheel in the bearing apparatus for wheels, (B) is a front view of the inner ring | wheel. (A) is sectional drawing which shows the other example of the inner ring in the bearing apparatus for wheels, (B) is a front view of the inner ring. It is a fragmentary sectional view of the bearing device for wheels concerning other embodiments of this invention. (A) is sectional drawing of the inner ring | wheel in the bearing apparatus for wheels, (B) is a front view of the inner ring | wheel. It is sectional drawing of the wheel bearing apparatus concerning other embodiment of this invention. It is sectional drawing of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Outer member 2 ... Inner member 2a ... Wheel mounting flange 2A ... Hub wheel 2B, 2B1, 2B2 ... Inner ring 3 ... Rolling element 4, 5 ... Rolling surface 6 ... Cage 7, 8 ... Seal 9 ... Inner ring Fitting surface 10 ... locking recess 11 ... locking projection 12 ... step 13 ... locking step

Claims (6)

An outer member having a plurality of rolling surfaces on the inner periphery, an inner member having a rolling surface facing each of the rolling surfaces on the outer periphery, and a double row interposed between the facing rolling surfaces. A wheel bearing device comprising: a rolling element, wherein the inner member includes a hub ring having a wheel mounting flange and an inner ring fitted to an outer periphery of the hub ring, and the wheel is rotatably supported with respect to the vehicle body. In
A locking recess is provided in a part of the inner ring inner diameter surface corresponding to the inboard side end of the hub ring in the circumferential direction, and the hub ring is reduced in diameter or enlarged by the fitting portion of the hub ring and the inner ring. The wheel bearing device is characterized in that a locking projection that is engaged by plastic flow is provided in the locking recess of the inner ring.   2. The wheel bearing device according to claim 1, wherein the locking recess has a groove shape extending in an axial direction from an end face on an inboard side of the inner ring.   In Claim 1, the said latching recessed part is formed in the corner | angular part of the end surface of the inboard side of the said inner ring | wheel, and an internal diameter, and the bottom face shape of this latching recessed part comprises circular arc shape in the cross section containing an inner ring | wheel central axis. Wheel bearing device that is in shape.   4. The step according to claim 1, wherein a step portion having a larger diameter than the inner diameter surface is provided on the entire circumference of the inner diameter surface of the inner ring corresponding to the inboard end side of the hub wheel. The engaging recess is provided in a part of the inner peripheral surface of the inner ring, and the hub ring is provided with a reduced diameter or an expanded diameter of the fitting portion between the hub ring and the inner ring, so that A wheel bearing device comprising: a locking step portion engaged with each other by plastic flow, and the locking protrusion.   5. The wheel bearing device according to claim 1, wherein the inner member has a rolling surface of each row formed on the hub wheel and the inner ring. 6.   In claim 5, the locking protrusion is formed by caulking to expand the inboard side end of the hub wheel, and the rolling surface in the hub wheel is a hardened surface-hardened surface, The inboard side end for performing the caulking is a non-heat treated portion, and the inner ring is hardened by quenching the entire inner ring from the surface to the core portion.

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