JP2003097577A - Bearing device for wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low cost bearing device for a wheel of which bonding part does not loosen even if a large moment load acts on the bearing during cornering or the like of a vehicle, increasing stiffness thereof while reducing weight and size. SOLUTION: A hardened rough part 24 is formed on an inner circumference of a hub wheel 21 provided in an outer diameter side of a fitting part of the hub wheel 21 and an outer side joint member 46. A fitting part 49b of the outer side joint member 46 is formed in hollow shape having a bottom part 49c. The fitting part 49b is expanded by static hydraulic pressure to bite into the rough part 24. The hub wheel 21 and the outer side joint member 46 thereby are plastically bonded as one body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wheel bearing device for supporting a wheel of an automobile and the like and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, a wheel bearing device for rotatably supporting a wheel with respect to a suspension device of an automobile has been reduced in weight for improving fuel consumption. In particular, in a drive wheel bearing device for an automobile such as a rear wheel of an FR vehicle, a front wheel of an FF vehicle, or all wheels of a 4WD vehicle, unitization for increasing rigidity is rapidly progressing for further steering stability.

As shown in FIG. 6, a conventional drive wheel bearing device comprises a hub wheel 50, a double-row rolling bearing 60, and a constant velocity universal joint 70, which are unitized. One of the inner races of the double row 51 is formed on the hub wheel 50, and the other 72
Is formed on the outer joint member 71 of the constant velocity universal joint 70. The hub wheel 50 integrally has a wheel mounting flange 53 for mounting a wheel (not shown) at one end of the cylindrical portion 52, and the wheel mounting flange 53 has a wheel mounting flange 53 for fixing the wheel at equidistant positions. The hub bolts 54 are planted. The inner raceway 5 is formed on the outer periphery of the cylindrical portion 52 near the wheel mounting flange.
1 is formed.

The constant velocity universal joint 70 includes an outer joint member 71,
It comprises a joint inner ring (not shown), a cage, and a torque transmission ball. The outer joint member 71 is the cup-shaped mouth portion 7
3, a shoulder portion 74 forming the bottom portion of the mouth portion 73, and a stem portion 75 extending in the axial direction from the shoulder portion 74, and a curved track groove 76 extending in the axial direction on the inner circumference of the mouth portion 73. And the inner raceway surface 7 is formed on the outer periphery of the shoulder 74.
Forming 2. With the end portion of the cylindrical portion 52 of the hub wheel 50 abutting against the shoulder portion 74, the stem portion 75 is attached to the cylindrical portion 5.
2 is fitted inside to position the hub wheel 50 and the outer joint member 71 in the axial direction, and defines the groove pitch of the inner raceways 51 and 72. The stem portion 75 is hollow by providing a through hole 77 communicating with the mouth portion 73. Therefore, in order to prevent the grease filled in the mouth portion 73 from leaking, the end plate 78 is attached to the end portion of the through hole 77 on the mouth portion 73 side.

The double row rolling bearing 60 includes an outer member 61 and a double row rolling element 62. The outer member 61 has a vehicle body mounting flange 63 for mounting the outer member 61 on a vehicle body (not shown).
Are integrally formed, and double rows of outer rolling surfaces 64, 64 are formed on the inner circumference. The outer rolling surfaces 64, 64, and the inner rolling surface 51 of the hub wheel 50 and the inner rolling surface 72 of the outer joint member 71, which are opposed to the outer rolling surfaces 64, 64, are rotatably held by cages 65, 65. The double-row rolling elements 62, 62 are accommodated. In addition, a seal 66 is provided at the end of the outer member 61,
67 is attached to prevent leakage of the lubricating grease sealed inside the bearing and intrusion of rainwater and dust from the outside.

A hardened concavo-convex portion 55 is formed on the inner peripheral surface of the cylindrical portion 52 of the hub wheel 50, and the inner diameter side of the stem portion 75 is expanded to form a concavo-convex portion 55 for fitting with the cylindrical portion 52. The outer joint member 71 and the hub wheel 50 are plastically coupled to each other. When such a diameter expansion is performed by press working, as shown in FIG. 7, after the stem portion 75 is fitted in the cylindrical portion 52 of the hub wheel 50, the hub wheel 50 is received by the receiving member 80.
The large diameter portion 81a formed to have a diameter slightly larger than the inner diameter of the through hole 77 of the stem portion 75 while supporting the side surface of the wheel mounting flange 53 and restraining the outer diameter portion of the hub wheel 50.
The caulking jig (punch) 81 having the above is pushed into the through hole 77 to expand the diameter (see Japanese Patent Application No. 2001-50846).

[0007]

In the bearing device for a wheel, the stem portion 75 of the outer joint member 71 needs to be formed in the hollow by the above-described diameter expansion method by the press working, and the bending moment load is applied to the device. In this case, the rigidity that suppresses the deformation was insufficient. On the other hand, if it is attempted to increase the rigidity by increasing the wall thickness of the stem portion 75 and the like without changing the size of the device, the diameter of the through hole 77 becomes small, which hinders press working, and There was a limit to the improvement in rigidity because it hindered weight reduction.

In the diameter expanding step, the punch 71, which is longer than the total length of the outer joint member 71, is inserted into the through hole 7 of the stem portion 75.
7, the diameter expanding device becomes large and the cycle time becomes long. Further, there is a problem that the work speed cannot be increased in order to prevent the material from cracking and the punch 81 from being seized when the diameter is expanded. In order to prevent the seizure of the punch 81 and improve the durability, the punch 81 is hardened by quenching and then at least the large diameter portion 81a is ground, and the surface of the punch 81 is hardened with titanium carbide (TiC) or the like. Has become expensive, and has caused a rise in manufacturing cost along with the problem of cycle time.

Further, not only the removal force of the end plate 78 must be controlled, but also the stem portion 75 must be controlled to have a desired diameter expansion amount. Therefore, the dimensional accuracy of the through hole 77 must be regulated, and It was unavoidable to increase the cost such as the number of parts to be processed.

The present invention has been made in view of the above circumstances, and achieves weight reduction and compactness, and even when a large moment load acts on the device, the fixing portion does not loosen, and An object of the present invention is to provide a low-cost bearing device for a wheel that can improve rigidity.

[0011]

[Means for Solving the Problems] In order to achieve the purpose,
The invention according to claim 1 of the present invention includes a double row rolling bearing for accommodating a double row rolling element between an inner member and an outer member and rotatably supporting a wheel. In a bearing device for a wheel, wherein a wheel mounting flange is formed integrally with a member or an outer member, a separate inner ring is externally fitted to the inner member, and the wheel is rotatably supported with respect to a vehicle body. By forming a hardened uneven portion on the inner diameter of the inner ring, the fitting portion of the inner member is a hollow shape having a bottom, and by expanding the fitting portion to bite into the uneven portion, A structure in which the inner member and the inner ring are integrally joined is adopted.

In such a so-called second-generation or third-generation driven wheel bearing device, it is possible to achieve weight reduction and compactness and increase the rigidity of the inner member.

According to a second aspect of the present invention, there is provided a wheel bearing device in which a hub wheel integrally having a wheel mounting flange at one end, a constant velocity universal joint, and a double row rolling bearing are unitized. For a wheel in which a separate inner ring is press-fitted into the cylindrical portion of the hub wheel, and the outer joint member of the constant velocity universal joint is fitted into the hub wheel to rotatably support the wheel with respect to the vehicle body. In the bearing device, a hardened uneven portion is formed on the inner diameter of the hub wheel, and the fitting portion of the outer joint member is formed in a hollow shape having a bottom portion, and the fitting portion is expanded in diameter to form the unevenness. By adopting a configuration in which the hub wheel and the outer joint member are integrally coupled by being bitten into the portion, the bearing device for drive wheels of the second and third generations also achieves weight reduction and compactness, and has an internal structure. The rigidity of the rectangular member can be increased.

More preferably, as in the invention described in claim 3, one inner rolling surface of the double row rolling bearing is on the outer circumference of the hub wheel, and the other inner rolling surface is on the outer circumference of the inner ring. In the bearing device for a third-generation drive wheel wheel formed as described above, the practicality is high in combination with the effects peculiar to the third generation, such as the improvement of rolling fatigue life of the bearing portion.

Further, according to a fourth aspect of the present invention, a hub wheel integrally having a wheel mounting flange at one end, a constant velocity universal joint, and a double-row rolling bearing are unitized, and the hub wheel and the constant velocity universal joint are integrated. An outer joint member is fitted, and one inner rolling surface of the double-row rolling bearing is formed on the outer circumference of the hub wheel, and the other inner rolling surface is formed on the outer circumference of the outer joint member. In a bearing device for a wheel in which a wheel is rotatably supported, a mating portion between the hub wheel and the outer joint member forms a cured uneven portion on a member disposed on the outer diameter side, and has an inner diameter. The fitting portion of the member disposed on the side is formed in a hollow shape having a bottom portion, and the fitting portion is expanded in diameter to bite into the uneven portion, thereby integrally coupling the hub wheel and the outer joint member. With the above configuration, that is, in the bearing device for wheels called the fourth generation Te, members can be minimized sites machining, the weight and size at a low cost can be reduced further. Further, it is possible to avoid insufficient rigidity with respect to bending moment load, which is one factor that has hindered the practical use of the conventional fourth generation structure.

According to a fifth aspect of the present invention, if the member on the outer diameter side of the fitting portion is the hub ring and the member on the inner diameter side is the outer joint member, the hub ring and the outer joint are formed. The workability of the step of plastically joining the members is good, and the manufacturing cost can be suppressed.

Further, as in the invention described in claim 6, if the member on the outer diameter side of the fitting portion is the outer joint member and the member on the inner diameter side is the hub wheel, the outer joint member is forged. Processing becomes easy, and the surface can be formed of case-hardening steel or the like that can be hardened by carburizing and quenching, so that the degree of freedom in selecting materials is expanded.

In the invention method according to claim 7 of the present invention, an outer member having a double row of outer rolling surfaces on the inner circumference,
An inner member having at least two members fitted to each other and having an inner rolling surface facing the double row rolling surface, and an inner member housed between the outer rolling surface and the inner rolling surface of the double row. A bearing for a wheel, comprising a double-row rolling bearing having a double-row rolling element, in which a wheel mounting flange is integrally formed on the inner member or the outer member, and the wheel is rotatably supported with respect to the vehicle body. In the method of manufacturing a device, of the inner member, a hardened concavo-convex portion is formed on a fitting portion of an outer diameter side member, and a fitting portion of an inner diameter side member is formed in a hollow shape having a bottom portion. Then
By expanding the diameter of this fitting portion, when the two members are made to bite into the uneven portion and plastically bond the two members, the member on the inner diameter side is engaged with one side in the axial direction of the member on the outer diameter side, and In a state where the other side in the axial direction of the member on the radial side is supported by the receiving member, a punch having a through hole is inserted into the member on the inner diameter side, and a closed portion is formed between the punch and the bottom portion, The closed portion is filled with a fluid from the through hole, and the fitting portion is expanded in diameter while pressurizing the fluid.

By adopting such a manufacturing method,
Without using a highly accurate and expensive punch as in the past, it is possible to minimize the machining to regulate the dimensional accuracy of each member and shorten the cycle time of the diameter expansion process. The manufacturing cost can be reduced.

Preferably, as in the invention described in claim 8, the member on the outer diameter side is a hub wheel integrally having a wheel mounting flange, and the member on the inner diameter side is an outer joint of a constant velocity universal joint. As a member, if the fitting portion of this outer joint member is hollow with an open end surface and the diameter of this fitting portion is expanded and connected to the hub wheel, the punch shape and diameter expansion equipment can be simplified. And the cycle time of the diameter expansion process can be further shortened.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a vertical sectional view showing a first embodiment of a wheel bearing device according to the present invention.

This wheel bearing device is applied to a driven wheel, and is constructed by uniting the inner member 1 and the outer member 10. In the following description, the side closer to the outside of the vehicle when assembled to the vehicle is referred to as the outboard side (left side in the drawing), and the side closer to the center is referred to as the inboard side (right side in the drawing).

The inner member 1 includes a hub wheel 2 and the hub wheel 2
It is composed of a separate inner ring 3 press-fitted into. The hub wheel 2 integrally has a wheel mounting flange 4 for mounting a wheel (not shown), and hub bolts 5 for fixing the wheel are planted at equally spaced circumferential positions of the wheel mounting flange 4. ing.
On the outer periphery of the hub wheel 2, an inner raceway surface 2a on the outboard side and a small diameter step portion 6 are formed. On the other hand, an inner rolling surface 3a on the inboard side is formed on the outer periphery of the inner ring 3, and the inner ring 3 is press-fitted into the small diameter step portion 6. Further, the uneven portion 3b hardened to the inner diameter of the inner ring 3 is formed, and the fitting portion of the small-diameter step portion 6 is expanded and bite into the uneven portion 3b by a method described later to integrally form the hub ring 2 and the inner ring 3. Is plastically coupled to. The end portion of the small-diameter step portion 6 of the hub wheel 2 is formed in a hollow shape having a bottom portion 6a. Due to the bottom portion 6a, the rigidity of the hub wheel 2 is almost equal to that of the solid structure, and the weight can be reduced. The bottom portion 6a may be formed in the vicinity of the stepped portion of the small-diameter step portion 6 so as to have a hollow shape with an open end surface.

The outer member 10 integrally has a vehicle body mounting flange 11 for mounting on a vehicle body (not shown) on the outer periphery,
Double rows of outer rolling surfaces 10a, 10a are formed on the inner circumference. On the other hand, the inner member 1 has a plurality of rows of inner rolling surfaces 2a facing the outer rolling surfaces 10a and 10a of the outer members 10,
3a are integrally formed on the outer circumferences of the hub ring 2 and the inner ring 3, respectively,
Double rows of rolling elements (balls) 12 are accommodated between the rolling surfaces 10a, 2a and 10a, 3a. The cages 13 and 13 rotatably retain the double row rolling elements 12 and 12. Further, seals 14 and 15 are attached to the ends of the outer member 10 to prevent leakage of the lubricating grease sealed inside the bearing and intrusion of rainwater, dust and the like from the outside. Further, an end cover 7 made of a steel plate press is further attached to an end portion of the outer member 10 to prevent dust and the like from the outside. In this case, the inboard seal 15 may be omitted or simplified.

As described above, the so-called third-generation wheel bearing device has been exemplified here, but a pair of inner rings are press-fitted into the hub ring to form the above-mentioned concavo-convex portion at least on the inner diameter of the inboard side inner ring to form the hub ring. A so-called second generation structure in which they are integrally connected may be used. Although the double row angular contact ball bearing in which the rolling elements 12 and 12 are balls has been illustrated here, the present invention is not limited to this, and a double row tapered roller bearing in which tapered rollers are used for the rolling elements may be used.

The hub wheel 2 is made of carbon such as S53C 0.40 to 0.40.
A seal land portion formed of medium carbon steel containing 0.60 wt% of the inner board 2a on the outboard side and slidingly contacting the seal 14 is subjected to induction hardening to harden the surface, and the small diameter step 6 is not hardened. I'm leaving. Inner rolling surface 2a
The surface hardness of 58 to 64 HR is the same as that of the outer raceway surface 10a.
By setting it in the range of C, a desired rolling fatigue life can be obtained. On the other hand, the inner ring 3 has a carbon content of 0.95
Made of high carbon chromium bearing steel consisting of 1.10 wt%,
The core is quenched and hardened.

For the driven wheel, in addition to the exemplified structure,
It may be a so-called outer ring rotating type in which the outer member integrally has a wheel mounting flange and the inner member integrally has a vehicle body mounting flange. In this case, in the third-generation structure, the inner ring on the outboard side is a separate body ring, and the hub ring is integrally plastically coupled by the above-described method.

FIG. 2 is a vertical sectional view showing a second embodiment in which the present invention is applied to a wheel bearing device on the driving side. The same parts and components as those in the above-described embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

This wheel bearing device has a third generation structure in which the inner member 20, the double-row rolling bearing 30, and the constant velocity universal joint 40 are unitized. Here, the inner member 20 refers to the hub wheel 21 and the outer joint member 41 of the constant velocity universal joint 40.

The hub wheel 21 integrally has a wheel mounting flange 22 for mounting a wheel (not shown), and hub bolts 5 for fixing the wheel are fixed to the wheel mounting flange 22 at equal positions on the circumference. It is being planted. On the outer periphery of the hub wheel 21, the inner raceway surface 21a on the outboard side and the small diameter step portion 23 are provided.
Is formed. The inner ring 3 which is a separate body is press-fitted into the small-diameter step portion 23 and assembled in a butted state with a shoulder portion 43 of an outer joint member 41 described later.

The double-row rolling bearing 30 includes an outer member 31 and double-row rolling elements 12, 12. The outer member 31 integrally has a vehicle body mounting flange 32 for mounting on a vehicle body (not shown) on the outer periphery, and has double rows of the outer rolling surface 3 on the inner periphery.
1a and 31a are formed. On the other hand, the inner member 20 is
Double rows of inner raceways 21a, 3a facing the outer raceways 31a, 31a of the outer member 31 are integrally formed on the outer circumferences of the hub wheel 21 and the inner race 3, respectively.
Double rows of rolling elements (balls) 12, 12 are housed between a, 21a and 31a, 3a.

The hub wheel 21 is made of carbon 0.40 such as S53C.
It is formed of medium carbon steel containing about 0.60 wt%, and the surface of the rolling land 21a including the outboard side, the seal land portion with which the seal 14 slides, and the small-diameter step portion 23 are hardened by induction hardening. On the other hand, the inner ring 3 has carbon of 0.9.
It is made of high carbon chromium bearing steel consisting of 5 to 1.10 wt%, and the core is quenched and hardened.

The outer joint member 41 of the constant velocity universal joint 40 is
It comprises a cup-shaped mouth portion 42, a shoulder portion 43 which is a bottom portion of the mouth portion 42, and a stem portion 44 which extends from the shoulder portion 43 in the axial direction. The stem portion 44 includes an inlay portion 44a into which the small-diameter step portion 23 of the hub wheel 21 is press-fitted and a fitting portion 44b. The fitting portion 44b is formed in a hollow shape that is open to the end face side (outboard side). The outer joint member 41 is made of carbon such as S53C 0.40 to 0.6.
A hard carbon hardened layer formed by induction hardening is formed on the surfaces of the track groove 42a formed in the inner circumference of the mouth portion 42 and extending in the curved shape in the axial direction, the shoulder portion 43, and the inlay portion 44a. The fitting portion 44b is unquenched and left as it is.

A hardened concavo-convex portion 24 is formed on the inner diameter of the outboard side of the hub wheel 21, and the fitting portion 44b of the stem portion 44 is formed.
The hub wheel 21 and the outer joint member 41 are integrated with each other by enlarging and biting them by a method described later.

FIG. 3A is a vertical sectional view showing a third embodiment according to the present invention. The same parts and components as those of the second embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

This wheel bearing device has a fourth-generation structure in which the inner member 25, the double-row rolling bearing 30, and the constant velocity universal joint 45 are unitized. Here, the inner member 25 indicates the outer joint member 46 of the hub wheel 21 and the constant velocity universal joint 45.

The hub wheel 21 has a wheel mounting flange 22 for mounting a wheel (not shown) at one end, and a hub bolt 5 for fixing the wheel is planted at equidistant positions on the circumference. An inner raceway surface 21 a and a small-diameter step portion 23 are formed on the outer circumference of the hub wheel 21.

The outer joint member 46 of the constant velocity universal joint 45 is
It comprises a cup-shaped mouth portion 47, a shoulder portion 48, and a stem portion 49 extending axially from the shoulder portion 48. A track groove 47a extending in a curved shape in the axial direction is formed on the inner periphery of the mouth portion 47, and an inboard side inner rolling surface 48a is formed on the outer periphery of the shoulder portion 48. The stem portion 49 includes an inlay portion 49a into which the small diameter step portion 23 of the hub wheel 21 is press fitted,
It is composed of a fitting portion 49b, and the end surface of the small-diameter step portion 23 of the hub wheel 21 and the shoulder portion 48 are abutted against each other for assembly.

A hardened concavo-convex portion 24 is formed on the inner diameter of the outboard side of the hub wheel 21, and the fitting portion 49b of the stem portion 49 is formed.
The hub ring 21 and the outer joint member 46 are integrated with each other by enlarging and biting them by a method described later.

Next, a method for expanding the diameter of the fitting portion 49b will be described with reference to FIG.
An explanation will be given based on (b). The punch A is inserted into the inner diameter of the fitting portion 49b to form a closed space with the hollow bottom portion 49c of the stem portion 49. The punch A has a stepped portion B and a through hole C. With the outer joint member 46 supported by the stepped portion B, a viscous fluid R such as silicon oil is filled into the closed space from the through hole C. The pressure P is momentarily applied to the viscous fluid R.
By applying, the fitting portion 49b is expanded in diameter as shown by an arrow. The viscous fluid R is not limited to silicon oil, and may be any fluid that can be expanded in diameter by hydrostatic pressure, and is not limited by its properties or specifications. However, if the fluid has a high viscosity such as silicone oil, a sealing means for sealing the closed space,
As in the present embodiment, the stepped portion B can be used as a substitute and simplification can be achieved.

FIG. 4A is a vertical sectional view showing a fourth embodiment according to the present invention. The difference from the above-described third embodiment is only the shape of the stem portion formed on the outer joint member, and the same reference numerals are given to the other same portions and the same parts, and detailed description thereof will be omitted.

The stem portion 49 'of the constant velocity universal joint 45' is
It is composed of an inlay portion 49a and a fitting portion 49b ', and this fitting portion 49b' has a hollow shape communicating with the mouth portion 47,
A bottom portion 49c 'is provided at the tip.

Next, a method for expanding the diameter of the fitting portion 49b 'will be described with reference to FIG. The punch A ′ is inserted into the inner diameter of the fitting portion 49b ′ to form a closed space with the bottom portion 49c ′ of the stem portion 49 ′. The punch A ′ is provided with a through hole C, and a viscous fluid R such as silicon oil is filled into the closed space from the through hole C. By instantaneously applying pressure P to the viscous fluid R, the fitting portion 49b 'is expanded in diameter as shown by the arrow.

FIG. 5 is a vertical sectional view showing a fifth embodiment according to the present invention. The same parts and components as those of the fourth embodiment illustrated in FIG. 4 are designated by the same reference numerals, and detailed description thereof will be omitted.

This wheel bearing device has a fourth-generation structure in which the inner member 35, the double-row rolling bearing 30, and the constant velocity universal joint 45 "are unitized. Here, the inner member 35 is used.
Is the outer joint member 4 of the hub wheel 36 and the constant velocity universal joint 45 ".
6 ”.

The hub wheel 36 integrally has a wheel mounting flange 37 for mounting a wheel (not shown) at one end,
Hub bolts 5 for fixing the wheels are planted at equal circumferential positions. Further, on the outer periphery of the hub wheel 36, an inner rolling surface 36a on the outboard side and a small diameter step portion 38 are formed.

The outer joint member 46 ″ is composed of a mouth portion 47 and a shoulder portion 48. A curved track groove 47 a extending in the axial direction is formed on the inner periphery of the mouth portion 47, and an inner portion is formed on the outer periphery of the shoulder portion 48. An inner rolling surface 48a on the board side is formed.
A cured uneven portion 48b is formed on the inner diameter of the shoulder portion 48,
The small-diameter step portion 38 of the hub wheel 36 is expanded into the uneven portion 48b and bites into the uneven portion 48b to integrally plastically couple the hub wheel 36 and the outer joint member 46 ". Similar to the above-described embodiment, the inner member 35 is formed. The hub wheel 36 that constitutes the outer joint member 46 "
Although the weight is reduced because it is formed in a hollow shape that communicates with the mouth portion 47, its rigidity is almost the same as that of the solid structure due to the presence of the bottom portion 39. Therefore, even if a bending moment load is repeatedly applied to the device, the joint does not loosen, the deformation is small, and the device has sufficient durability.

This outer joint member 46 "has no major axis stem portion, and includes the uneven portion 48b, the inner raceway surface 48a,
Also, the track groove 47a can be hardened by carburizing and quenching without carburizing without being limited to the above-mentioned surface hardening by induction hardening. Therefore, SCr415, etc.
It is also possible to use case-hardened steel, which has good forgeability, and expands the freedom of material selection.

Although the embodiment of the present invention has been described above, the present invention is not limited to the embodiment and is merely an example, and does not depart from the scope of the present invention. Of course, the present invention can be implemented in various forms, and the scope of the present invention is shown by the description of the scope of claims, and the equivalent meanings described in the scope of claims and all within the scope Including changes.

[0050]

As described above in detail, the bearing device for a wheel according to the present invention has the following remarkable effects. In a bearing device for a wheel in which an inner member and a double row rolling bearing, or a constant velocity universal joint are unitized,
Since the inner member is formed in a hollow shape having a bottom,
It has the same rigidity as a solid structure, while solving the intended technical issues such as weight reduction and compactness. Therefore, even when a bending moment load is applied, the joint portion is not particularly loosened, the deformation is small, and sufficient durability can be secured. In addition, since at least two members that fit together are plastically connected by a simple diameter expansion that applies hydrostatic pressure, there is no need to use an expensive punch, the cycle time of the diameter expansion process is short, and the manufacturing cost is low. Can be suppressed. Further, since the diameter is not mechanically expanded by inserting the punch, there is no restriction on the dimensional accuracy of the member, and strict machining or the like that causes a rise in manufacturing cost is not required.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a first embodiment of a wheel bearing device according to the present invention.

FIG. 2 is a vertical cross-sectional view showing a second embodiment of the wheel bearing device according to the present invention.

FIG. 3 (a) is a vertical cross-sectional view showing a third embodiment of the wheel bearing device according to the present invention. (B) It is an important section sectional view for explaining a diameter expansion method.

FIG. 4 (a) is a vertical cross-sectional view showing a fourth embodiment of the wheel bearing device according to the present invention. (B) It is an important section sectional view for explaining a diameter expansion method.

FIG. 5 is a vertical sectional view showing a fifth embodiment of the wheel bearing device according to the present invention.

FIG. 6 is a vertical cross-sectional view showing a conventional wheel bearing device.

FIG. 7 is an explanatory diagram showing a conventional diameter expansion method.

[Explanation of symbols]

1, 20, 35 ... Internal member 2, 21, 36 ... Hub hub 2a, 3a, 21a, 36a ... Inside rolling surface 3 ......... Inner ring 3b, 24, 48b ... 4, 22, 37 ... ・ ・ ・ Wheel mounting flange 5 ... Hub bolt 6, 23, 38 ... ・ ・ ・ ・ ・ Small diameter step 6a, 49c, 49c ', 39 ... bottom 7 ......... End cover 10, 31 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outer member 10a, 31a ... Outer rolling surface 11, 32 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Vehicle mounting flange 12 ......... Rolling elements 13 ......... Cage 14,15 ... Seal 30 ... Double-row rolling bearing 40, 45, 45 ', 45 "... Constant velocity universal joint 41, 46, 46 ', 46 "... Outer joint member 42, 47 ... Mouse part 42a, 47a ..... track grooves 43, 48 ... Shoulder 48a ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner rolling surface 44, 49, 49 '... Stem part 44a, 49a ... Inlay part 44b, 49b, 49b '... Fitting portion 50 ......... Hub wheel 51, 72 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner rolling surface 52 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Cylindrical part 53 ......... Wheel mounting flange 54 ... Hub bolt 55 ... 60 ・ ・ ・ ・ ・ Double row rolling bearing 61 ・ ・ ・ ・ ・ ・ ・ ・ Outer member 62 ......... Rolling elements 63 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Vehicle mounting flange 64 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outer rolling surface 65 ・ ・ ・ ・ ・ ・ ・ ・ Cage 66, 67 ... Seal 70 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Constant velocity universal joint 71 ... Outer joint member 73 ... Mouse part 74 ......... Shoulder 75 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Stem part 76 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Track groove 77 ... 78 ・ ・ ・ ・ ・ ・ End plate 80 ・ ・ ・ ・ ・ ・ ・ ・ Receiving member 81 ・ ・ ・ ・ ・ ・ ・ ・ Crimping jig 81a ..... Large diameter part A, A '... Punch B ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Stepped part C ... R: Viscous fluid P ・ ・ ・ ・ ・ ・ ・ ・ ・ Pressure

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) B60B 35/18 B60B 35/18 A F16C 19/18 F16C 19/18 19/38 19/38 33/60 33/60 43 / 04 43/04 F16D 3/20 F16D 3/20 Z F term (reference) 3J017 AA02 AA05 BA10 CA01 DA10 DB08 HA04 3J101 AA01 AA32 AA43 AA54 AA62 AA72 BA53 BA54 BA56 BA65 BA77 FA04 FA15 FA31 FA44 FA46 FA51 FA53 GA03 GA14

Claims (8)

[Claims] 1. A double-row rolling bearing that accommodates a double-row rolling element between an inner member and an outer member and rotatably supports a wheel, wherein the inner member or the outer member has a wheel. In a wheel bearing device in which a mounting flange is integrally formed, a separate inner ring is externally fitted to the inner member, and the wheel is rotatably supported with respect to a vehicle body, the inner ring is hardened to the inner diameter. While forming the uneven portion,
The inner member and the inner ring are integrally coupled by making the fitting portion of the inner member hollow and having a bottom, and enlarging the fitting portion to bite into the uneven portion. Bearing device for wheels. 2. A wheel bearing device in which a hub wheel integrally having a wheel mounting flange at one end, a constant velocity universal joint, and a double row rolling bearing are unitized, and a separate inner ring is a cylinder of the hub wheel. In a wheel bearing device in which the outer joint member of the constant velocity universal joint is fitted into the hub wheel by press fitting, and the wheel is rotatably supported with respect to the vehicle body, the inner diameter of the hub wheel is hardened. While forming the concavo-convex portion, the fitting portion of the outer joint member is formed in a hollow shape having a bottom portion, and the fitting portion is expanded in diameter to bite into the concavo-convex portion to form the hub wheel and A bearing device for a wheel, wherein the outer joint member and the outer joint member are integrally connected. 3. The wheel bearing device according to claim 2, wherein one inner raceway of the double row rolling bearing is formed on the outer circumference of the hub wheel and the other inner raceway is formed on the outer circumference of the inner race. . 4. A hub wheel integrally having a wheel mounting flange at one end, a constant velocity universal joint, and a double row rolling bearing are unitized, and the hub wheel and an outer joint member of the constant velocity universal joint are fitted together, One of the inner rolling surfaces of the double-row rolling bearing is formed on the outer circumference of the hub wheel, and the other inner rolling surface of the double row rolling bearing is formed on the outer circumference of the outer joint member to rotatably support the wheel with respect to the vehicle body. In the bearing device for a wheel, the fitting portion of the hub wheel and the outer joint member forms a cured uneven portion on a member arranged on the outer diameter side, and the fitting of the member arranged on the inner diameter side. Forming a hollow portion having a bottom portion, and expanding the diameter of the fitting portion so as to bite into the uneven portion, whereby the hub wheel and the outer joint member are integrally coupled to each other. apparatus. 5. The wheel bearing device according to claim 4, wherein a member on the outer diameter side of the fitting portion is the hub wheel, and a member on the inner diameter side is the outer joint member. 6. The wheel bearing device according to claim 4, wherein a member on the outer diameter side of the fitting portion is the outer joint member, and a member on the inner diameter side is the hub wheel. 7. An outer member having a double row outer raceway surface on an inner circumference thereof, and an inner member having an inner raceway surface facing the double row raceway surface and comprising at least two members fitted to each other. A double row rolling bearing having an inner member and a double row rolling element accommodated between the outer rolling surface and the inner rolling surface of the double row, wherein a wheel mounting flange is provided on the inner member or the outer member. In a method for manufacturing a wheel bearing device in which a wheel is rotatably supported with respect to a vehicle body, an uneven portion cured to a fitting portion of an outer diameter side member of the inner member And the fitting part of the member on the inner diameter side,
When forming a hollow shape having a bottom portion and expanding the diameter of this fitting portion so as to bite into the uneven portion and plastically bond both members, the inner diameter side is formed on one side in the axial direction of the outer diameter side member. Of the outer diameter side member is supported by a receiving member on the other side in the axial direction of the outer diameter side member, a punch having a through hole is inserted into the inner diameter side member, and the punch is inserted between the punch and the bottom portion. A method for manufacturing a bearing device for a wheel, comprising: forming a closed portion on the inner surface of the bearing, filling the closed portion with a fluid through the through hole, and expanding the diameter of the fitting portion while pressurizing the fluid. 8. The outer diameter side member is a hub wheel integrally having a wheel mounting flange, while the inner diameter side member is an outer joint member of a constant velocity universal joint, and a fitting portion of the outer joint member is The method for manufacturing a wheel bearing device according to claim 7, wherein the end surface is open, and the fitting portion is expanded in diameter and joined to the hub wheel.