JP2003072311A - Bearing system for axle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing system for an axle free to generalize main constitutional parts such as a hub shaft, etc., while corresponding to patterns of wheel mounting screw holes different from each other in accordance with car models and makers. SOLUTION: This bearing system for the axle applies structure not to directly mount a brake disc rotor 3 and a wheel 7 on the hub shaft 1 but to mount it through an attachment 4. Consequently, it becomes possible to prepare a plurality kinds of the attachments 4 in accordance with the number of the mounting screw holes and central circular diameters PCD of the wheels different from each other in accordance with the models and the makers of the automobiles, to select the required kind of the attachments 4 from them, to mount them on the hub shaft 1 free to connect and disconnect to and from it, to generalize the main constitutional parts (such as the hub shaft 1, a double row rolling bearing 2, etc.), and to improve generality.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axle bearing device for supporting wheels on a vehicle body.

[0002]

2. Description of the Related Art The basic construction of a conventional axle bearing device is as follows.
A hub shaft having a flange for mounting a brake disc rotor extending radially outward on the outer periphery of the vehicle outer side, and a hub shaft externally fitted and attached to the outer periphery of the hub shaft so as not to come off from the hub shaft. A double-row rolling bearing rotatably supported with respect to the vehicle, and a brake disc rotor externally mounted on a surface of the flange on the vehicle outer side.

Generally, the number of bolt mounting holes provided in the wheel portion of the wheel and the center circle diameter PCD of the bolt mounting holes differ depending on the type of vehicle and the manufacturer.

Therefore, in the conventional axle bearing device,
Since the brake disc rotor has a structure which is directly attached to the flange of the hub axle, it is necessary to manufacture a plurality of hub axles each having a flange corresponding to a mounting hole of a different wheel depending on the type of automobile and the manufacturer.

Further, the outer diameter of the flange of the hub axle is made as large as possible because it is necessary to secure an outer dimension sufficient for holding the brake disc rotor in a stable posture. Therefore, the deviation between the maximum outer diameter portion of the flange and the minimum outer diameter portion is large,
The number of steps for manufacturing the hub axle by forging increases.

[0006]

In the above-mentioned conventional example, since the brake disc rotor has a structure which is directly attached to the flange of the hub axle, a plurality of types of hub axles which differ depending on the type of automobile and the manufacturer are to be used. It is pointed out that manufacturing costs and storage costs are high because they must be manufactured on separate production lines.

Further, since it is necessary to increase the outer diameter of the flange portion of the hub shaft, the deviation between the flange and the minimum outer diameter portion becomes large, and many steps are required when manufacturing the hub shaft by forging. Has to be repeated, and manufacturing costs are soaring.

In view of such circumstances, the present invention is capable of selectively attaching an attachment of a type required for each object of use to a hub shaft in a bearing device for an axle and reducing the manufacturing process of the hub shaft. Adopted a structure that can.

[0009]

According to a first aspect of the present invention, there is provided a bearing device for an axle according to claim 1, wherein a radially outwardly projecting portion is provided as a maximum outer diameter portion on the outer periphery of the vehicle outer side. A hub shaft, a double row rolling bearing that is mounted on the outer periphery of the hub shaft in a region closer to the vehicle inner side than the convex portion, and rotatably supports the hub shaft with respect to the vehicle body; An attachment that is externally fitted and attached to a surface of the vehicle outer side with respect to a region of the vehicle outer side with respect to the convex portion while holding the brake disc rotor integrally rotatably, and the attachment that is attached to the vehicle outer side of the hub axle. A fastening member for holding and fixing the attachment from the axial direction with the convex portion, wherein the attachment is an annular plate set to an outer diameter dimension for holding the brake disc rotor in a stable posture, A plurality of bolts for mounting the wheel are mounted in a state of being penetrated in the axial direction at several places of the circle, and the protruding size of the convex portion is limited to a degree slightly larger than the central hole of the attachment. The deviation between the maximum outer diameter portion of the convex portion and the minimum outer diameter portion of the outer peripheral surface of the hub axle is set to be permanently small.

According to a second aspect of the present invention, there is provided a bearing device for an axle according to the second aspect, wherein in the first aspect, the fastening member is
It is a nut and is screwed onto a screw shaft portion provided on the vehicle outer side of the hub shaft.

According to a third aspect of the present invention, there is provided a bearing device for an axle according to claim 3, wherein in the first or second aspect, the outer periphery of the hub axle is located in a vehicle outer side region with respect to the convex portion.
A cylindrical surface for centering is provided in which the central hole of the attachment is fitted.

According to a fourth aspect of the present invention, there is provided a bearing device for an axle according to any one of the first to third aspects,
A cylindrical portion for centering into which a center hole of the brake disc rotor is fitted is provided in an area on the vehicle outer side with respect to the convex portion on the outer periphery of the hub axle.

According to a fifth aspect of the present invention, there is provided a bearing device for an axle according to any one of the first to fourth aspects,
Cut-and-raised pieces cut and raised so as to project along the axial direction are provided at several places on the inner diameter side of the attachment, and the outer diameter surface of each cut-and-raised piece is the brake disc rotor. Has a curved shape so as to circumscribe the center hole.

In short, according to the present invention, the brake disc rotor and the wheels are not directly attached to the hub axle, but are attached via an attachment. Therefore, an attachment of a necessary type can be attached to the hub axle depending on the object of use. It becomes possible to selectively attach the components to each other, and the main components (such as the hub shaft and the double-row rolling bearing) can be shared, and the versatility can be enhanced. Also, since the hub disc does not need to have a brake disc rotor mounting flange, the deviation between the maximum outer diameter and the minimum outer diameter of the hub shaft can be set as small as possible, and the hub shaft is manufactured by forging. It is possible to reduce the number of steps required.

The second structure is limited to the structure in which the nut is used as the fastening member in the first structure.

Further, in the third structure, the attachment can be simply assembled to the hub shaft so that the hub shaft can be easily centered coaxially with the hub shaft.

In the fourth structure, the brake disc rotor is simply attached to the hub shaft,
The hub shaft can be easily coaxially centered.

Further, in the above fifth structure, the brake disc rotor can be centered only by a simple process of providing a cut-and-raised piece on the attachment, which is preferable.

[0019]

DETAILED DESCRIPTION OF THE INVENTION The details of the present invention will be described below with reference to the embodiments shown in the drawings.

1 to 3 show an embodiment of the present invention. 1 is a sectional view of a bearing device for an axle according to a first embodiment of the present invention, FIG. 2 is an exploded sectional view of FIG. 1, and FIG.
It is a disassembled perspective view of FIG.

The axle bearing device shown in the figure is a solid hub axle 1.
And a double row rolling bearing 2 as an example of a rolling bearing, and a brake disc rotor 3 of a disc brake device is attached to the vehicle outer side of the hub axle 1 via an attachment 4.

The hub axle 1 has a cylindrical portion 11 along its axial direction on the vehicle inner side, and the threaded shaft portion 1 on the vehicle outer side.
2, and a flange 13 extending radially outward is provided in the middle of the axial direction. The flange 13 corresponds to the convex portion described in claim 1.

The double-row rolling bearing 2 has a single outer ring 21 having two rows of raceway grooves, a plurality of balls 22 as rolling elements arranged in two rows, and two crown-shaped cages 23. The inner ring 24 having a single row of raceway grooves is provided, and the outer peripheral portion of the expanded diameter portion 19 provided on the vehicle inner side of the flange 13 of the hub axle 1 serves as the inner ring raceway surface. A radially outward flange 25 is provided at an axially intermediate portion of the outer peripheral surface of the outer race 21, and the flange 25 is attached to the knuckle 5, which is a part of the vehicle body, with a bolt 6.

In this embodiment, when the hub axle 1 is manufactured by forging, it is provided on the outer periphery of the hub axle 1 for stabilizing the posture of the brake disc rotor 3 for the purpose of reducing the number of steps. The outer diameter of the flange 13 is made as small as possible, and the attachment 4 for stabilizing the posture of the brake disc rotor 3 is used instead.

The attachment 4 is an annular plate having a central hole 41 for inserting the hub shaft 1 in the central portion thereof, and bolt mounting holes 44 penetrating in the thickness direction are provided at several positions on the circumference thereof. Has been. This bolt mounting hole 4
4, bolts 72 for fixing the brake disc rotor 3 and the wheels 7 are inserted in a state in which they are not rotated.

By the way, usually, the number of bolt mounting holes provided in the wheel portion of the wheel 7 and the center circle diameter PCD of the bolt mounting holes differ depending on the type of vehicle and the manufacturer. Therefore, a plurality of types of attachments 4 are prepared for each vehicle type and manufacturer of the automobile for which the bearing device for an axle is used, and a required type of attachment 4 is selected from these attachments and detached from the hub axle 1. It is preferable to be able to attach it. In this way, the brake disc rotor 3 and the wheels 7 are connected to the hub axle 1.
If it is attached directly to the vehicle through the attachment 4, it is not necessary to manufacture a plurality of axle bearing devices with different specifications for each vehicle model and manufacturer on separate production lines, increasing versatility. You can

By the way, since the attachment 4 needs to stabilize the posture of the brake disc rotor 3 as described above, for example, the SC material and SPC of JIS standard are used.
It is preferable to manufacture it with a high-strength material such as a material, and the outer diameter thereof is preferably set to a dimension that can be loosely fitted into the inner diameter portion of the hat of the disk rotor 3.

By suppressing the ratio of the minimum outer diameter and the maximum outer diameter of the hub axle 1 to, for example, 2.2 or less, it is possible to reduce the number of steps for manufacturing the hub axle 1 by forging. , Leading to cost reduction.

Further, the flange 13 provided on the hub axle 1
The maximum outer diameter of the outer ring 21 is limited to be slightly larger than the central hole of the attachment 4, and is preferably set to be equal to or smaller than the outer diameter of the outer ring 21.

Next, an assembling form of each of the above-mentioned components will be described.

First, after assembling the double row rolling bearing 2 to the hub shaft 1, the cylindrical portion of the hub shaft 1 on the free end side (see the chain double-dashed line in FIG. 1) is radially outside by rolling caulking or the like. By bending in a direction and crimping the inner ring 24 to a predetermined portion on the vehicle inner side, a required preload is applied to the double-row rolling bearing 2. Reference numeral 16 is attached to the caulking portion.

Then, the attachment 4 to which the bolt 72 is attached is applied to the flange 13 from the vehicle outer side. At this time, the attachment 4 is centered by fitting the inner diameter portion 41 of the attachment 4 onto the outer peripheral surface of the cylindrical portion 14 of the hub axle 1 provided on the vehicle outer side of the flange 13. The fitting interference of this part is an intermediate fit.

Subsequently, the brake disc rotor 3 is applied to the attachment 4 from the vehicle outer side. At this time, the inner diameter portion 31 of the brake disc rotor 3
Is externally fitted to the outer peripheral surface of the cylindrical portion 15 of the hub axle 1 to center the brake disc rotor 3. The fitting interference of this part is a tight fit so that accurate centering can be performed.

Thereafter, the flat washer nut 51 is screwed into the screw shaft portion 12 provided on the vehicle outer side of the hub axle 1, so that the attachment 4 and the brake disc rotor 3 are connected by the flange 13 and the flat washer nut 51. The attachment 4 and the brake disc rotor 3 are sandwiched between the hub shaft 1 and
Fixed against.

Thereafter, the wheel 7 is applied to the brake disc rotor 3 from the vehicle outer side, and the wheel 72 is attached to the bolt 72 by screwing a nut (not shown). The centering of the wheel 7 is performed by aligning the outer peripheral surface of the seat portion 52 of the seat bolt 51 with the inner diameter portion 71 of the wheel 7.
It can be performed by fitting with.

As described above, according to the axle bearing device of the present embodiment, the outer diameter of the flange 13 provided to stabilize the posture of the brake disc rotor 3 on the outer periphery of the hub shaft 1 can be changed. Since the attachment 4 for stabilizing the posture of the brake disc rotor 3 is used instead of the hub shaft 1, the hub axle 1 is made smaller.
When forging is manufactured, the number of steps can be reduced, and the manufacturing cost of the hub axle 1 can be reduced.

Moreover, since the brake disc rotor 3 and the wheels 7 are not directly attached to the hub axle 1 but are attached via the attachment 4, the attachment 4
A plurality of types are prepared for each vehicle type and manufacturer of the automobile for which the axle bearing device is used, and the attachment 4 of the required type can be selected from these and can be detachably attached to the hub axle 1. As a result, it is not necessary to manufacture a plurality of axle bearing devices having different specifications for each vehicle type and manufacturer of automobiles on different production lines, and versatility can be enhanced.

The present invention is not limited to the above embodiment, and various modifications and applications are possible.

(1) In the above-described first embodiment, an example in which the inner ring on the vehicle outer side of the double-row rolling bearing 2 is also used as the hub shaft is given. However, as in the second embodiment shown in FIG. The present invention also includes a structure in which the double row rolling bearing 2 is also provided with a dedicated inner ring 28 on the vehicle outer side without being used also as an inner ring. In addition, in the double row rolling bearing 2 of this type, the rolling element is the ball 2 as in the third embodiment shown in FIG.
Instead of 2, tapered roller 22A may be used.

(2) In the first embodiment, as the bearing device for the axle, the type used for the driven wheels is taken as an example, but instead of this, the type used for the drive wheels as in the fourth embodiment shown in FIG. The present invention can also be applied to the axle bearing device. The axle bearing device of the illustrated example differs from the structure shown in FIG. 1 in that the hub shaft 1 is hollow.
Although not shown, an axle shaft is inserted into the hollow portion of the hub shaft 1 through a constant velocity joint and coupled.

(3) As for the attachment 4 shown in the first embodiment, as in the fifth embodiment shown in FIG. 7, cuts are made in several places of the circumference of the inner diameter portion, and these cuts are made in the axial direction on the vehicle outer side. A plurality of cut-and-raised pieces 42 formed by bending 90 ° along the shape may be provided. The outer diameter surface of each cut and raised piece 42 is curved,
It is preferable that the inner diameter portion 31 of the brake disc rotor 3 is externally fitted by an interference fit so that the brake disc rotor 3 can be centered.

(4) In the first embodiment, as in the sixth embodiment shown in FIG. 8, even if the attachment 4 and the brake disc rotor 3 are still attached to the hub axle 1, the axle bearing device is mounted on the knuckle 5. Devise so that it can be attached and removed. That is, in the attachment 4, notches 45 are provided between the bolt mounting holes 44 provided at several places on the circumference and at positions corresponding to the bolt mounting holes 26 of the outer ring 21, respectively. Tool insertion holes 34 are provided between the bolt mounting holes 33 provided at several positions on the rotor 3 and at positions corresponding to the bolt mounting holes 26 of the outer ring 21. The notch portion 45 and the tool insertion hole 34 are set to a size large enough to allow the tool 9 for operating the bolt 6 for attaching the outer ring 21 to the knuckle 5 to pass therethrough in a non-contact manner. As a result, the attachment 4
Even with the brake disc rotor 3 still attached to the hub axle 1, the tool 9 is used to operate the bolt 6 for attaching the outer ring 21 to the knuckle 5, which is a part of the vehicle body, from the outer side of the vehicle. The main body can be attached and detached.

(5) In the first embodiment, the inner ring 24 is prevented from coming off from the hub axle 1 by caulking, but instead of this, a seventh embodiment shown in FIGS.
As described above, the plate 53 can be used. In this case, radially outwardly projecting portions 17 are provided at four locations on the outer peripheral surface of the hub axle 1 on the free end side on the vehicle inner side. on the other hand,
The plate 53 is an annular plate having a central hole 54 through which the free end of the hub axle 1 on the vehicle inner side is inserted, and the inner diameter of the central hole 54 has a convex portion on the hub axle 1. A cutout portion 55 for inserting 17 is provided. Then, the plate 53 is fitted and inserted on the free end side of the hub axle 1,
The plate 53 is rotated 45 ° in the circumferential direction while being applied to the vehicle inner side end surface 29 of the inner ring 24. The distance between the end surface 29 and the vehicle outer side end surface 18 of the convex portion 17 is set to be the same as the thickness of the plate 53. In such a configuration, by tightening the plain washer nut 51, a required preload can be applied to the double-row rolling bearing 2. Of course, the numbers of the convex portions 17 and the cutout portions 55 are not limited to four.

(6) In the first embodiment, the flange 13
Has a continuous shape in the circumferential direction, but is discontinuous in the circumferential direction,
That is, the present invention also includes a structure in which convex portions are intermittently provided at equal intervals around the circumference.

[0045]

In the bearing device for an axle according to the invention of claims 1 to 5, the brake disc rotor and the wheels are not directly attached to the hub axle but are attached via an attachment. A plurality of types of attachments are prepared according to the number of mounting screw holes on the different wheels and the center circle diameter PCD, and the required type of attachment is selected from these attachments to be detachably attached to the hub axle. It becomes possible to share the main components (hub shaft, double row rolling bearing, etc.)
Versatility can be improved. Moreover, since it is not necessary to manufacture a plurality of hub axles that differ for each vehicle type and manufacturer of automobiles on separate production lines, the hub axle manufacturing cost
Storage costs can be reduced.

Further, since the projecting dimension of the convex portion, which is the maximum outer diameter portion of the hub shaft, is set to be as small as possible with respect to the minimum outer diameter portion, when manufacturing the hub shaft by forging, The number can be reduced, and the manufacturing cost of the hub axle can be reduced.

In particular, according to the second aspect of the invention, the attachment and the convex portion provided with the brake disc rotor on the hub shaft are screwed to the screw shaft portion provided on the vehicle outer side of the hub shaft in the axial direction. Since a structure for holding and fixing using a nut is adopted, the attachment and the brake disc rotor can be securely attached to the hub shaft by a relatively simple fastening means such as nut screwing. .

According to the third aspect of the invention, the attachment of the attachment can be easily carried out by simply assembling the attachment to the hub axle, thereby making it possible to easily align the attachment coaxially with the hub axle. This is preferable because the work can be simplified.

According to the invention of claim 4, the brake disc rotor is simply attached to the hub shaft,
Since it can be easily centered coaxially with the hub shaft, the work for mounting the brake disc rotor can be simplified, which is preferable.

Further, in the invention of claim 5, the brake disc rotor can be centered only by a simple process of providing a cut-and-raised piece on the attachment, which is preferable.

[Brief description of drawings]

FIG. 1 is a sectional view of a bearing device for an axle according to a first embodiment of the present invention.

FIG. 2 is an exploded sectional view of FIG.

FIG. 3 is an exploded perspective view of FIG.

FIG. 4 is a sectional view of an axle bearing device according to a second embodiment of the present invention.

FIG. 5 is a sectional view of an axle bearing device according to a third embodiment of the present invention.

FIG. 6 is a sectional view of an axle bearing device according to a fourth embodiment of the present invention.

FIG. 7 is an exploded perspective view of a bearing device for an axle according to a fifth embodiment of the present invention.

FIG. 8 is an exploded perspective view of a bearing device for an axle according to a sixth embodiment of the present invention.

FIG. 9 is a sectional view of an axle bearing device according to a seventh embodiment of the present invention.

FIG. 10 is an exploded perspective view showing a main part of FIG.

11 is a perspective view showing a state in which the plates of FIG. 10 are assembled.

[Explanation of symbols]

1 hub axle 2 Double row rolling bearing 3 brake disc rotor 4 attachments 7 wheels

Claims (5)

[Claims] 1. A hub shaft having a maximum outward diameter portion provided with a radially outwardly projecting portion on the outer periphery of the vehicle outer side, and an outer periphery of the hub shaft that is externally mounted on a region on the vehicle inner side of the projecting portion. A double-row rolling bearing that rotatably supports the hub shaft with respect to the vehicle body, and a brake disc rotor that integrally rotates on a surface on the vehicle outer side with respect to a region on the vehicle outer side of the protrusion on the outer periphery of the hub shaft. An attachment that is externally fitted and attached in a state in which the attachment is held in a possible manner; and a fastening member that is attached to the vehicle outer side of the hub shaft and holds and fixes the attachment in the axial direction with the convex portion, wherein the attachment , Consisting of an annular plate set to an outer diameter dimension that holds the brake disc rotor in a stable posture,
A plurality of bolts for wheel mounting are attached to the circumference at several places in a state of penetrating in the axial direction, and the projecting size of the convex portion is limited to a degree slightly larger than the central hole of the attachment. The deviation between the convex portion, which is the maximum outer diameter portion, and the minimum outer diameter portion on the outer peripheral surface of the hub axle is set to be permanently small, and the bearing device for an axle is characterized. 2. The axle bearing device according to claim 1, wherein the fastening member is a nut and is screwed to a screw shaft portion provided on the vehicle outer side of the hub shaft. Bearing device. 3. The bearing device for an axle according to claim 1, wherein a centering cylindrical surface in which a center hole of the attachment is fitted in a region of the outer periphery of the hub axle that is closer to the vehicle outer side than the convex portion. A bearing device for an axle, comprising: 4. The axle shaft bearing device according to claim 1, wherein a center hole of the brake disc rotor is fitted in a region of the outer periphery of the hub shaft that is closer to the vehicle outer side than the convex portion. A bearing device for an axle, comprising a cylindrical portion for projecting. 5. The bearing device for an axle according to any one of claims 1 to 4, wherein cut-and-raised pieces cut and raised so as to project along the axial direction are provided at several circumferential positions on the inner diameter side of the attachment. A bearing device for an axle, wherein an outer diameter surface of each cut-and-raised piece is provided in a curved shape so as to circumscribe a center hole of the brake disc rotor.