JP5372548B2 - Fastening structure for vehicle wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a wheel disc from cracking in the vicinity of a nut means, in a fastening structure of wheels for a vehicle. <P>SOLUTION: A disc 21 is fastened to a hub flange 12 by fastening the nut means 30 screwed into hub bolts 15 toward the disc 21 with the disc 21 of a wheel fitted to the hub flange 12 and with the hub bolts 15 inserted into the bolt holes 23 of the disc 21. On the disc 21, an annular clearance groove 24a is formed facing the peripheral edge on the disc side of each nut means 30. A surface area between the bolt hole 23 of the disc 21 and the clearance groove 24a functions as a receiving surface 25a to receive a fastening force by each nut means 30. The peripheral edge of each nub means 30 facing the disc is separated from the bottom surface 24x (clearance surface) of each clearance groove 24a. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a structure for fastening a vehicle wheel to a hub flange.

  In order to fasten the vehicle wheel to the hub flange of the vehicle, a plurality of bolt holes separated in the circumferential direction are formed in the disk of the wheel. On the other hand, a plurality of hub bolts separated in the circumferential direction are fixed to the hub flange.

  The wheel is attached to the hub by tightening nut means screwed into the hub bolt toward the disc while the disc is applied to the hub flange and the hub bolt is inserted into the bolt hole of the disc. Fasten to the flange.

In Patent Document 1, an annular relief groove is formed on the wheel disc so as to face the peripheral edge of the hub flange, so that a concentrated load is avoided from being applied to the peripheral edge of the hub flange, thereby preventing cracks due to fretting fatigue. ing.
JP-A-8-268001

  However, Patent Document 1 does not consider the possibility that a crack caused by fretting fatigue occurs in the wheel disk due to the concentrated load from the periphery of the nut means. Therefore, in order to ensure the safety of the wheel, it has been impossible to optimize the disk thickness and reduce the weight.

  In order to solve the above-described problems, the present invention provides a structure in which a disk of a vehicle wheel is fastened to a hub flange, wherein the disk receives a nut means screwed into a hub bolt, and a hub flange side from the receiving surface. And a flank face opposed to the periphery of the nut means and spaced away from the periphery.

  According to the above configuration, since the surface of the disk that faces the periphery of the nut means is separated from the periphery as a flank, it is possible to avoid a concentrated load from being applied to the disk from the periphery. As a result, it is possible to prevent the disk from cracking and to improve durability.

  Preferably, the nut means includes a nut screwed to the hub bolt, and a washer interposed between the nut and the disk, and a peripheral edge of the washer faces the flank.

Preferably, a receiving surface and a flank surface of the disk are formed on both surfaces of the disk.
According to this configuration, it is possible to combine the wheels without distinguishing between the case where one wheel is fastened to the hub and the case where two wheels are fastened to the hub.

Preferably, the disk is formed with an annular relief groove facing the periphery of the nut means, and the bottom surface of the relief groove is provided as the relief surface.
According to this configuration, the flank can be formed on the disk by relatively simple processing.
In addition, since the inner receiving surface and the outer surface can be compared across the clearance groove, even if the receiving surface wears down due to repeated contact received from the nut means and the disk thickness decreases, the use limit due to this wear is reduced. Can be visualized, and strength reduction can be predicted. This further improves the reliability of the wheel.

  According to the present invention, it is possible to prevent the wheel disk from cracking due to the concentrated load from the periphery of the fastening nut means. Further, it is not necessary to increase the disk thickness in order to prevent this crack, and the weight of the wheel can be reduced.

  Hereinafter, a wheel fastening structure for a large vehicle adopting an ISO type (flat seat) fastening method according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a single-wheel type wheel fastening structure 1 on the front side of the vehicle, and FIG. 4 shows a double-wheel type wheel fastening structure 2 on the rear side.

  First, the front side wheel fastening structure 1 will be described. In this fastening structure 1, one wheel 20 is fastened to the hub 10 of the vehicle. The hub 10 has a fitting portion 11 having a circular cross section and an annular hub flange 12 formed on the outer periphery thereof. A brake drum 13 is fixed to the surface of the hub flange 12 on the vehicle side.

In the hub flange 12, hub bolts 15 are fixed to a surface opposite to the vehicle at intervals in the circumferential direction. The hub bolt 15 extends parallel to the central axis of the hub 10 and is orthogonal to the wheel mounting surface of the hub flange 12.

  As shown in FIGS. 1 and 3, the wheel 20 has a disk 21 and a rim 22. The disk 21 has a cup shape and includes a circular flat plate portion 21a and a skirt portion 21b having a tapered shape such that the diameter increases as the distance from the periphery of the flat plate portion 21a increases. The peripheral edge of the skirt portion 21b is fixed to the inner periphery of the rim 22 by welding.

  A large-diameter hub hole 28 is formed at the center of the flat plate portion 21a, and a plurality of bolt holes 23 are formed around the hub hole 28 at equal intervals in the circumferential direction.

  The wheel 20 is fastened to the hub 10 by nut means 30 including a nut 31 and a washer 32. Specifically, in the flat plate portion 21 a of the disk 21 of the wheel 20, one surface of the annular portion surrounding the hub hole 28 (inner side as viewed from the wheel axial direction, that is, the surface on the vehicle body side) is in surface contact with the hub flange 12. Hit in state. In this contact state, the fitting portion 11 of the hub 10 is fitted into the hub hole 28 of the disk 21 to position the wheel 20, and the hub bolt 15 is inserted into the bolt hole 23.

  Next, the washer 32 is inserted into the hub bolt 15, the nut 31 is screwed, and the nut 31 is tightened to fasten the disk 21 of the wheel 20 to the hub flange 12.

  Next, features of the present invention will be described. Annular relief grooves 24 a and 24 b that are concentric with the bolt hole 23 are formed on the outer surface (the surface on the opposite side of the vehicle body) and the inner surface (the surface on the vehicle body side) of the flat plate portion 21 a.

  On both surfaces of the flat plate portion 21a of the disk 21, annular regions between the bolt holes 23 and the relief grooves 24a, 24b are provided as receiving surfaces 25a, 25b, and the bottom surfaces 24x of the relief grooves 24a, 24b are escaped. Offered as a face. The flank 24x is shifted from the receiving surfaces 25a and 25b toward the thickness center.

  The relief grooves 24a and 24b are preferably formed by press working from the viewpoint of productivity and strength to impart work hardening and compressive residual stress, but may be cut. In the case of cutting, in order to improve the strength of the relief grooves 24a, 24b and the bottom surface 24x, it is preferable to leave compressive stress on the bottom surfaces 24x of the relief grooves 24a, 24b and the vicinity thereof by shot peening.

  The depth of the escape grooves 24a and 24b is preferably 0.4 to 1.0 mm. This is because as the depth increases, the strength of the disk 21 decreases. Further, the radius of curvature of the bottom surface 24x of the relief grooves 24a and 24b is 5 mm or less when the outer diameter of the washer 32 (part facing the disk 20 of the nut means 30) is 55 mm or less, and the outer diameter of the washer 32 is 55 mm. In the above case, it should be 5 mm or more.

In the fastening state, the washer 32 strongly hits the receiving surface 25a on the outer side of the flat plate portion 21a of the disk 21 in a surface contact state. The problem is the concentrated load applied to the disk 21 by the peripheral edge of the washer 32 facing the disk 21. In the present embodiment, a clearance groove 24a is formed in the disk 21 so as to face the periphery of the washer 32, and its bottom surface, that is, the clearance surface 24x is shifted to the hub flange 12 side from the receiving surface 25a. Since the peripheral edge of the clearance is away from the clearance surface 24x of the clearance groove 24a and does not contact the disk 21, no concentrated load is applied to the disk 21.
As a result, it is possible to prevent the occurrence of cracks due to fretting fatigue from occurring in the vicinity of the periphery of the washer 32 in the disk 21, and it is not necessary to increase the thickness of the disk 21 in order to prevent this crack from occurring.

The receiving surface 25a is worn by repeated contact received from the nut means 30, and the thickness of the disk 21 is thereby reduced. In this case, if the nut means 30 is removed, the inner receiving surface 25a and the outer surface can be compared with the escape groove 24a interposed therebetween. Therefore, the use limit due to this wear can be visualized, and a decrease in strength can be predicted. The bottom surface 24x of the escape groove 24a may be painted with a color different from that of other parts. Thereby, the recognition effect can be made clear. The same applies to the escape groove 24b.
The inner clearance groove 24b has no role in the single-wheel wheel fastening structure 1 because it is located on the vehicle side, that is, the hub flange 12 side. In the structure 2, it plays the same role as the outer clearance groove 24a in the single-wheel type wheel fastening structure 1 described above.

  Next, the double wheel type wheel fastening structure 2 will be described with reference to FIG. In the fastening structure 2, two wheels 20 having the same structure as that used in the fastening structure 1 are set on the hub flange 12 so that the flat plate portions 21 a of the disks 21 are overlapped. A common hub bolt 15 is inserted into the bolt holes 23 of the two wheels 20, and the disks 21 of the two wheels 20 are fastened to the hub flange 12 by common nut means 30 screwed into the hub bolts 15.

  In the fastening structure 2, the escape groove 24 b formed in the flat plate portion 21 a of the disk 21 of the wheel 20 on the outer side (opposite the vehicle) faces the peripheral edge of the washer 32, and the escape groove 24 a of the fastening structure 1 Since the same action is performed, it is possible to prevent the occurrence of cracks due to fretting fatigue of the flat plate portion 21a of the wheel 20.

  In the above embodiment, since the relief grooves 24a and 24b are formed on both surfaces of the flat plate portion 21a of the wheel 20, the wheel 20 is used for both the single wheel type wheel fastening structure 1 and the double wheel type wheel fastening structure 2. be able to.

When the wheel 20 is not used as the single-wheel and double-wheel fastening structures 1 and 2 as described above, the annular groove is formed only on the surface facing the peripheral edge of the washer 32 as in the reference example shown in FIG. 24 may be formed.

In the reference example shown in FIG. 6, a raised portion 29 is formed around the bolt hole 23 in the flat plate portion 21a instead of forming the annular relief groove. In this case, the surface of the raised portion 29 becomes a receiving surface 29a that receives the washer 32, and the inclined surface around the raised portion 29 becomes a flank 29b.
Also in the above reference example , since the peripheral edge of the washer 32 floats facing the flank 29b, it is possible to prevent the occurrence of cracks due to fretting fatigue of the flat plate portion 21a.

FIG. 7 shows still another reference example. In this reference example , instead of processing the flat plate portion 21a of the disk , the peripheral edge portion of the washer 32 'is inclined with respect to the central flat plate portion. The nut 31 is placed on the flat plate portion of the washer 32 '.
Since the peripheral edge of the washer 32 'is inclined away from the flat plate portion 21a in the radial direction and outward direction, the peripheral edge of the contact area with the flat plate portion 21a forms an obtuse angle in the washer 32'. . Therefore, the crack prevention of the flat board part 21a can be expected.

The present invention is not limited to the above embodiment, and various aspects can be adopted. For example, the nut means may be constituted by a single nut having a special shape such as a seated nut, for example, instead of a combination of a nut and a washer. In this case, the peripheral edge of the nut facing the disk is circular like the washer in the above embodiment, and faces the flank.
The brake drum 13 may be fixed between the hub flange 12 and the wheel 20.
The disk 21 may have a simple disk shape without having a taper shape, and in that case, the disk 21 is fixed to the inner periphery of the rim 22 by welding.

It is sectional drawing of the wheel fastening structure for single-wheel vehicles which makes 1st Embodiment of this invention. It is sectional drawing which expands and shows the principal part of the fastening structure in FIG. It is a front view of the wheel. It is sectional drawing of the wheel fastening structure for multi-wheels vehicles in the embodiment. It is a principal part expanded sectional view of the wheel disc used for the reference example of the wheel fastening structure for vehicles . It is a principal part expanded sectional view of the other reference example of the wheel fastening structure for vehicles . It is a principal part expanded sectional view which shows the other reference example of the wheel fastening structure for vehicles.

DESCRIPTION OF SYMBOLS 1, 2 Wheel fastening structure 10 Hub 12 Hub flange 15 Hub bolt 20 Wheel 21 Disc 21a Flat plate part 23 Bolt hole 24, 24a, 24b Relief groove 24x Relief surface 25a, 25b Receiving surface 29 Raised part 29a Receiving surface 29b Relief surface 30 Nut Means 31 Nut 32 Washer

Claims (3)

One wheel is fastened to the front hub of the vehicle, two wheels are fastened to the rear hub,
Each hub includes a fitting portion, a hub flange projecting radially and outwardly from the fitting portion, and a plurality of hub bolts disposed so as to surround the fitting portion and projecting from the hub flange to the opposite side of the vehicle And
Each wheel includes a disc and a rim provided on the periphery of the disc,
The disc has a hub hole formed in the center thereof into which the fitting portion of the hub is fitted, an annular flat plate portion surrounding the hub hole, and a plurality of bolt holes formed in the flat plate portion through which the hub bolt is inserted. And
The flat plate portion has a flat first surface located on the protruding side of the rim and a flat second surface located on the opposite side to the protruding direction of the rim,
On the front side, the wheel is disposed with its rim facing the vehicle, and the nut means screwed to the hub bolt is tightened toward the second surface of the flat plate portion of the wheel, whereby the wheel is flat. The board is fastened to the hub flange,
On the rear side, the inner wheel close to the vehicle is arranged with the rim facing the vehicle, the outer wheel far from the vehicle is arranged with the rim facing the other side of the vehicle, and the flat portions of the inner wheel and the outer wheel are arranged. The flat surface of these two wheels can be obtained by tightening the nut means, which is overlapped so that the second surface thereof is in surface contact, and screwed into the hub bolt toward the first surface of the flat plate portion of the outer wheel. In the vehicle wheel fastening structure in which the portion is fastened to the hub flange ,
The front wheel, the rear inner wheel, and the rear outer wheel are combined,
An annular relief groove surrounding the bolt hole is formed on both the first surface and the second surface of the flat plate portion of all the wheels, and an area between the bolt hole and the relief groove is provided as a receiving surface. And
On the front side, the nut means hits the receiving surface of the second surface of the flat part of the wheel, and the periphery of the nut means faces the bottom surface of the relief groove formed on the second surface,
On the rear side, the nut means hits the receiving surface of the first surface of the flat portion of the outer wheel, and the periphery of the nut means faces the bottom surface of the relief groove formed on the first surface. Fastening structure for vehicle wheels. The nut means has a nut screwed to the hub bolt, and a washer interposed between the nut and the disk, and the periphery of the washer faces the bottom surface of the escape groove. The fastening structure for a vehicle wheel according to claim 1. The clearance groove has a depth of 0.4 to 1.0 mm, the bottom surface of the clearance groove forms a circular arc, and the radius of curvature thereof is such that the outer diameter of the portion of the nut means facing the disk is 55 mm or less. The vehicle wheel fastening structure according to claim 1 or 2, wherein the width is 5 mm or less, and the outer diameter is 5 mm or more when the outer diameter is 55 mm or more.

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