JP2003294031A - Rolling bearing unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the following problems in a rolling bearing unit, in which precision of a product is worse because a supporting shaft is formed by hot processing, the number of necessary processes is increased because subsequent processing such as machining is required, and overall manufacturing costs are also increased. <P>SOLUTION: A first inner ring member 11 is provided to be light in weight by forming a tubular blank to a hollow cylindrical shape when compared with a conventional solid cylindrical shape in section, and consequently, reduction of rotary torque for the rolling bearing unit is feasible. Upon comparing with a conventional manufacturing process of the first inner ring member such as a hot forging process, a new process dispenses a large scale facilities, and is capable of forming finished components with high precision. Consequently, grinding time for obtaining necessary accuracy of a raceway surface is shortened as accuracy of the finished components is relatively better than that of the conventional components. Further, grinding works are almost not necessary for other parts except the raceway surface, and overall manufacturing costs of the first inner ring member can be reduced. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling bearing device, and more particularly to a rolling bearing device suitable for supporting wheels on a vehicle body.

[0002]

2. Description of the Related Art FIG. 3 is a schematic diagram of a rolling bearing device used for an axle on the driven wheel side. The rolling bearing device is rotatably supported around the axis through an outer ring member 50 which is supported non-rotatably on the vehicle body side and a plurality of rows of balls 51a and 51b radially inward of the outer ring member 50. And an inner ring member 52. The inner ring member 52 is a hub wheel 53 for mounting a brake disc and a tire wheel.
And an axle 55. The hub wheel 53 has an inner raceway surface of the balls 51a in one row on the outer peripheral surface thereof.

The axle 55 is provided on the outer peripheral surface thereof with the balls 51 of the other row.
b has an inner ring raceway surface. The outer ring member 50 has, on its inner peripheral surface, outer ring raceway surfaces of the balls 51a and 51b in both rows. The axle 55 is formed into a solid cross section by hot forging and has a shaft portion 54 that is inserted into a center hole of the hub wheel 53.

[0004]

In the above conventional rolling bearing device, the axle 55 has a solid cross section and is formed by hot forging. Therefore, in manufacturing the same, an expensive and large-scale equipment is required such as a press machine for applying a large pressure. Further, since it is difficult to ensure product accuracy in the axle shaft 55 manufactured by hot forging, a lot of post-processing such as turning and polishing is required, resulting in an increase in the number of processes.

[0005]

In order to solve the above-mentioned problems, a rolling bearing device according to the present invention comprises an outer ring member and first and concentric radially inner parts of the outer ring member.
A second inner ring member, and a plurality of rows of rolling elements interposed between the outer ring member and each inner ring member, wherein the first inner ring member is formed in a hollow cylindrical shape, and the second inner ring member is A center hole into which the first inner ring member can be inserted, and an end portion of the first inner ring member inserted into the center hole of the second inner ring member is crimped to an end surface of the second inner ring member. .

By forming the first inner ring member of the inner ring members into a hollow cylindrical shape as described above, when the inner ring member rotates about its axis, the rotational torque is reduced. Become.

Further, the first inner ring member is formed by cold forging. Alternatively, the first inner ring member is formed by cold forging a tubular material.

When the first inner ring member is cold-forged or the tubular material is cold-forged into a hollow cylindrical shape having a predetermined cross-sectional shape as in the above-mentioned construction, the rolling bearing device is manufactured. , Does not require large-scale equipment. Further, it is possible to shorten the polishing processing time for making the raceway surface of the rolling element have a required accuracy. Therefore, the manufacturing of the product is facilitated and the manufacturing cost is reduced.

An inner ring raceway surface having a double row outer ring raceway surface on the inner circumferential surface thereof, the outer ring member being non-rotatably supported by the vehicle body, and an outer ring surface corresponding to the outer ring raceway surface on one side of the outer ring member. With an axle having an inner ring raceway surface corresponding to the outer ring raceway surface on the other side of the outer ring member, and
The hub wheel is externally fitted to the outer peripheral surface of the other side of the axle and is caulked by the end of the axle to prevent the hub wheel from slipping off. The hub wheel is interposed between the outer raceway surface and the inner raceway surface. And a rolling element, the axle is formed into a hollow cylindrical shape by cold forging.

By forming the axle into a hollow cylindrical shape by cold forging as in the above structure, no large-scale equipment is required when manufacturing the rolling bearing device. Further, it is possible to shorten the polishing processing time for making the raceway surface of the rolling element have a required accuracy. Therefore, the manufacturing of the product is facilitated and the manufacturing cost is reduced.

By forming the outer ring member and the second inner ring member by cold forging from a tubular material like the first inner ring member or the axle, the manufacturing of the product is further facilitated and the manufacturing cost is reduced. To be done. Further, the second inner ring member can also be formed by cold forging a plate-shaped material.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION A rolling bearing device according to an embodiment of the present invention will be described below with reference to the drawings. In the figure, the rolling bearing device is applied to an axle rolling bearing device on the driven wheel side. FIG. 1 is a cross-sectional view showing the overall configuration of a rolling bearing device according to an embodiment of the present invention, and FIG. 2 is a side view of the rolling bearing device from the vehicle inner side. As shown in the figure, this rolling bearing device 1 includes an outer ring member 2 and a rolling element 2
It has rows of balls 4, 5 and an inner ring member 6.

The outer ring member 2 is formed by hot forging. The outer ring member 2 has a double row outer ring raceway surface on its inner peripheral surface. The outer ring member 2 includes a support flange 20.
Have. The support flange 20 is formed at an intermediate position in the axial direction of the outer ring member 2 so as to project radially outward. By mounting the support flange 20 on a knuckle that is incorporated in the vehicle body side (not shown), the outer ring member 2 is supported non-rotatably around the axis with respect to the vehicle body. A cover 22 is fitted to an end portion of the outer ring member 2 on the vehicle inner side. The cover 22 is for securing a space 21 for accommodating a vehicle speed sensor (not shown). The balls 4 and 5 in each row are held at equal positions in the circumferential direction by a crown-shaped cage 3.

The inner ring member 6 is composed of a first inner ring member 11 and a second inner ring member 13 which are arranged concentrically with the outer ring member 2, respectively. The first inner ring member 11 has a function as an axle, and on the vehicle inner side thereof, a track portion 7 having an outer peripheral surface corresponding to one outer ring track surface as an inner ring track surface of the balls 4 in one row.
Are formed. The first inner ring member 11 has a reduced diameter portion 14 on the vehicle outer side. The first inner ring member 11 having such a configuration is formed into a hollow cylindrical shape as shown in the figure by cold forging from a tubular material.

The second inner ring member 13 is formed with a raceway portion 12 whose outer peripheral surface corresponding to the other outer raceway surface is the inner raceway surface of the ball 5 on the other side, and which projects radially outward from this raceway portion 12. Hub flange 10. The second inner ring member 13 is used as a hub wheel for mounting the brake disc 8 and the tire wheel 9. The second inner ring member 13 has a center hole 12a at the center of the track portion 12 into which the reduced diameter portion 14 of the first inner ring member 11 is fitted. The second inner ring member 13 is formed from a tubular, ring-shaped, or flat material by cold forging. The first inner ring member 11 also has a second
The crimping portion 13 that is crimped to the end surface of the inner ring member 13
a.

A guide member 23, which serves as a guide when the brake disc 8 and the tire wheel 9 are attached to the hub flange 10, is provided so as to cover the caulked portion 13a. This guide member 23 is also called a spigot member. The guide member 23 is formed in the center of the guide member 23, and is inserted into the inner hollow portion 24 of the first inner ring member 11 by press fitting, and a radially outer portion from the end of the cylindrical fit portion 25. It has a flat plate portion 26 whose diameter is expanded in a direction, and an annular guide portion 28 which is bent from the radially outer end portion of the flat plate portion 26 toward the vehicle inner side. The guide member 23 having such a configuration is integrally formed from a plate-shaped material by cold forging.

The brake disc 8 and the tire wheel 9 each have a central hole (reference numeral omitted), and these central holes are fitted so as to be guided to the outer peripheral surface of the guide portion 28 of the guide member 23.

Reference numeral 30 in the drawing denotes a hub bolt. The hub bolt 30 is press-fitted into the insertion hole 29 at a predetermined position in the circumferential direction of the hub flange 10. Brake disc 8
The tire wheel 9 and the tire wheel 9 each have a central hole along the guide portion 28 of the guide member 23, and the hub bolt 3
0 is inserted into the board surface and is overlaid on the hub flange 10 as shown by a virtual line in the figure. The brake disc 8 and the tire wheel 9 are fixed to the hub flange 10 by screwing a nut member (not shown) onto the hub bolt 30.

The rolling bearing device 1 has a sealing device 16 for sealing the annular space 15 between the outer ring member 2 and the second inner ring member 13 on the vehicle outer side thereof. The sealing device 16 is an elastic seal body having a cored bar fitted on the inner peripheral surface of the vehicle outer side end of the outer ring member 2 and a lip attached to the cored bar and contacting a facing portion of the second inner ring member 13. It consists of and.

A procedure for manufacturing the rolling bearing device 1 having the above structure will be described. First, the balls 4 and 5 of each row are assembled to the outer ring member 2 while being held by the crown-shaped cage 3. Subsequently, the first inner ring member 11 is assembled so as to be inserted into the outer ring member 2 from the vehicle inner side, and the second inner ring member 13 is assembled from the vehicle outer side. At this time, the reduced diameter portion 1 of the first inner ring member 11
The inner ring members 11 and 13 are aligned at the radial position so that the inner ring member 4 can be smoothly inserted into the center hole 12a of the second inner ring member 13.

With the reduced diameter portion 14 of the first inner ring member 11 inserted in the center hole 12a of the second inner ring member 13, the diameter of the end surface of the first inner ring member 11 is expanded so that the second inner ring member 1 is expanded.
The end face 3 is crimped to form a crimped portion 13a on the first inner ring member 11. In this way, by caulking the end surface of the first inner ring member 11 with respect to the end surface of the second inner ring member 13,
The second inner ring member 13 is retained from the first inner ring member 11 so that both inner ring members 11 and 13 are integrally rotated around the axis, and a predetermined preload is applied to the balls 4 and 5 in both rows. To be done.

After that, the cylindrical fitting portion 2 of the guide member 23
5 is press-fitted into the inner space portion 24 of the first inner ring member 11 so that the guide portion 28 abuts on the vehicle outer side end surface of the second inner ring member 13.
Assemble to 1. After that, the outer ring member 2 is attached to the support flange 20.
The brake disc 8 and the tire wheel 9 are attached to the hub flange 10 by assembling to the vehicle body.

When the brake disc 8 and the tire wheel 9 are mounted on the hub flange 10 in this manner, their central holes are guided to the outer peripheral surface of the guide portion 28 of the guide member 23.

Rolling bearing device 1 manufactured in this way
Then, when the vehicle travels, the inner ring member 6, that is, the first inner ring member 11 and the second inner ring member 6 rotate together with the rotation of wheels (not shown).
The inner ring member 13 rotates around the axis.

By the way, the first inner ring member 11 is made of a tubular material and is formed into a hollow cylindrical shape having a predetermined cross-sectional shape. Can be made lighter, and as a driven wheel, it is possible to reduce the rotational torque.

Further, since the first inner ring member 11 is made of a tubular material and is formed into a hollow cylindrical shape having a predetermined sectional shape by cold forging, when it is formed by hot forging as in the conventional case. Compared with the above, even a small-scale and inexpensive facility can be used, and the first inner ring member 11 can be formed with high accuracy.

That is, in the case of hot forging, the surface accuracy of the product is low, and in particular, a long polishing time is required to make the inner ring raceway surface of the ball 4 have the required accuracy, and in some cases, the portion other than the inner ring raceway surface is also required. It required polishing. On the other hand, when the first inner ring member 11 and the second inner ring member 13 are formed by cold forging using a tubular material, the accuracy of the product is good, so that the inner ring raceway surface has the required accuracy. The polishing time can be shortened and almost no polishing is required for parts other than the inner ring raceway surface. This can significantly reduce the manufacturing cost.

Further, as shown in FIG. 3, conventionally, the raceway portion of the hub wheel 53 (second inner ring member), the hub flange and the guide member have been integrally formed by hot forging. A large-scale device was needed. However, as in this embodiment, the guide member 2
By forming 3 by cold forging as a member separate from the raceway portion 12 and the hub flange 10, the capacity of the hot forged portion becomes small, and it is possible to manufacture with a cheaper and smaller-scale device than the conventional one. .

Further, since the guide member 23 has a function of covering the caulked portion 13a of the first inner ring member 11, muddy water or the like enters from between the end face of the second inner ring member 13 and the caulked portion 13a. It has a function to prevent

The present invention is not limited to the above embodiment. In the above embodiment, an example of the inner ring rotating type is shown as the rolling bearing device 1, and the guide member 23 is used as the inner ring member 1.
I attached it to 1. However, the present invention can also be applied to an outer ring rotating type rolling bearing device having the hub flange 10 on the outer ring member 2. In this case, the guide member 23 is attached to the inner peripheral surface of the end portion of the outer ring member 2. Alternatively, as another embodiment, for example, the first inner ring member 11 and the second inner ring member 11
It can also be applied to a rolling bearing device having a structure in which the inner ring member 13 is spline-fitted. In any case, by making the guide member 23 separate from the inner ring members 11 and 13 or the outer ring member 2, at least the first inner ring member 11 can be formed by cold forging using a tubular material. As a result, the rotation torque can be reduced and the manufacturing cost can be significantly reduced.

In each of the above-mentioned embodiments, the tubular or ring-shaped or flat plate-shaped material for the inner ring members 11 and 13, the outer ring member 2 and the guide member 23 can be formed as thin as the strength allows. It is also excellent in terms of weight reduction, workability, and manufacturing cost.

Further, although the rolling bearing device 1 in the above-described embodiment has been shown to be used on the driven wheel side of a vehicle, the present invention is not limited to this and can be applied to the driving wheel side of a vehicle.

[0033]

As is clear from the above description, according to the present invention, not only is expensive and large-scale equipment unnecessary, but also the raceway surface of the rolling element is made to have the required accuracy with respect to the inner ring member. Post-processing time such as polishing or turning can be shortened or omitted, and thus manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is an overall sectional view of a rolling bearing device according to an embodiment of the present invention.

FIG. 2 is a side view of the same.

FIG. 3 is an overall sectional view of a conventional rolling bearing device.

[Explanation of symbols]

1 Rolling bearing device 2 Outer ring member 10 Hub flange 11 First inner ring member 13 Second inner ring member 13a Caulking part 23 Guide member 24 inner space

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3J101 AA02 AA32 AA43 AA54 AA62                       BA53 DA09 FA44 GA02 GA03                 4E087 AA10 BA18 CB01 HA42 HA82                       HB03

Claims (4)

[Claims] 1. An outer ring member, first and second inner ring members which are concentrically arranged radially inward of the outer ring member, and a plurality of rows interposed between the outer ring member and each inner ring member. The first inner ring member is formed in a hollow cylindrical shape,
The inner ring member has a center hole into which the first inner ring member can be inserted, and the end portion of the first inner ring member inserted into the center hole of the second inner ring member is caulked to the end surface of the second inner ring member. Has been
A rolling bearing device characterized by the above. 2. The rolling bearing device according to claim 1, wherein the first inner ring member is formed by cold forging.
A rolling bearing device characterized by the above. 3. The rolling bearing device according to claim 1, wherein the first inner ring member is formed by cold forging a tubular material. 4. An outer ring member having a double row outer ring raceway surface on an inner circumferential surface thereof, the outer ring member being non-rotatably supported by a vehicle body, and an outer ring surface corresponding to an outer ring raceway surface on one side of the outer ring member. And an outer peripheral surface having an inner ring raceway surface corresponding to the outer ring raceway surface on the other side of the outer ring member, and being externally fitted to the other side outer peripheral surface of the axle and crimped by the end portion of the axle. A hub wheel that is retained from the axle,
A rolling bearing device comprising: rolling elements that are respectively interposed between the outer ring raceway surfaces and the inner ring raceway surfaces, wherein the axle is formed into a hollow cylindrical shape by cold forging.