JP3686350B2 - Automotive disc wheel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bolt wheel structure for fixing to an axle in an automotive disc wheel.
[0002]
[Prior art]
Conventionally, an automobile disc wheel is provided in a hub by inserting an axle to which the hub is connected into a hub hole provided in a central portion, and in a bolt hole provided in a hub mounting surface formed around the hub axle. In general, the disc wheel is fixed to the axle by inserting the bolt portion and tightening the disc wheel with the bolt portion and the nut. Here, a nut tightening seat surface formed by forming a seat surface shape matching the shape of the nut is provided on the inner peripheral edge of the bolt hole, so that the nut comes into surface contact with the nut tightening seat surface. Then, the disk wheel and the axle are fixed with sufficient force by the surface pressure that the nut tightening seat receives from the force of tightening the nut. Further, the surface contact between the nut and the nut-clamping seating surface allows the disc wheel and the axle to be fixed and held for a relatively long time.
[0003]
[Problems to be solved by the invention]
As such nuts, automotive wheel nuts with tapered surface shapes, tapered nuts for tapered seats, or automotive wheel nuts with spherical convex surfaces, spherical nuts for spherical seats are used, and automobile manufacturers The nut of any of the above types is used. However, since most automobile manufacturers use tapered nuts, commercially available automotive disk wheels have nut-clamping seats with tapered surfaces to accommodate tapered nuts. There are many cases. Therefore, when a user who owns a car of a certain automobile manufacturer who uses a spherical nut purchases a new disc wheel, he / she purchases a disc wheel corresponding to the spherical nut at the car manufacturer, It is necessary to purchase a new taper nut along with the purchase.
[0004]
On the other hand, when a spherical nut is used for a disc wheel corresponding to a tapered nut, the spherical nut and the nut tightening seating surface are only in line contact with each other, so that the force for fixing the disc wheel to the axle becomes insufficient. In such a case, an external force such as vibration received from the road surface during traveling of the automobile may cause the disc wheel and the axle to loosen easily, possibly leading to damage and accidents associated therewith.
[0005]
SUMMARY OF THE INVENTION An object of the present invention is to propose an automotive disc wheel having a nut tightening seating surface that can cope with both a taper nut and a spherical nut and can be properly fixed to an axle by tightening these nuts.
[0006]
[Means for Solving the Problems]
The present invention relates to a steel disc wheel for an automobile in which a bolt portion formed on a hub of an axle is inserted into a bolt hole provided on a hub mounting surface and fixed to an axle by tightening a taper nut or a spherical nut. The nut tightening seating surface formed on the inner periphery of the wheel bolt hole is formed by coupling the inner tapered surface to which the tapered nut is surface-bonded and the outer spherical concave surface to which the spherical nut is surface-bonded inward and outward. This is a steel disc wheel for automobiles.
[0007]
In such a configuration, since the nut tightening seating surface has a configuration in which the tapered surface and the spherical concave surface are coupled inward and outward, when tightened with the taper nut, the surface is pressure-bonded to the tapered surface, and the spherical nut When tightened with, the surface is pressure-bonded to the spherical concave surface. Therefore, regardless of whether a taper nut or a spherical nut is used, the disc wheel and axle can be fixed and held with sufficient force by the required tightening torque, so the user can select the disc wheel without worrying about the nut shape. And can be purchased. In addition, there is an advantage that the tightening failure of the nut can be reduced from the product side.
[0008]
As such a nut tightening seat surface, it is proposed that a tapered surface is formed on the inner side and a spherical concave surface is formed on the outer side so as to be coupled to the tapered surface. That is, the tapered surface and the spherical concave surface which is formed continuously to the inside and outside direction the nut clamping bearing surface, a tapered surface is formed on the inner side, in which the spherical concave surface is assumed to be formed on the outer side. Generally, bolts and nuts having the same nominal diameter have the same head diameter, so that the spherical nut has a spherical convex surface that swells outward as compared to a tapered nut. Therefore, by disposing the spherical concave surface corresponding to the spherical nut shape outside the tapered surface, even if either a spherical nut or a tapered nut with the same nominal diameter is used, the surface is properly crimped. ing.
[0009]
Here, it is proposed that the contact width of the tapered surface and the spherical concave surface constituting the nut tightening seat surface is 1.0 mm or more. As a result, the surface pressure applied by tightening the nut with the required tightening torque on the contact surface with the nut formed by setting the contact width to 1.0 mm or more is appropriately fixed to the axle of the disc wheel. It can be necessary force. Here, the surface pressure acting on the contact surface between the nut and the nut tightening seat surface increases in proportion to the size of the contact surface. Therefore, the larger the contact surface, the more the force that fixes the disc wheel and the axle. growing. The size of the contact surface is determined by the diameter and contact width of the nut tightening seat surface. Since the nominal diameters of bolts and nuts of general automobiles are the same standard, the bolt hole diameter and the diameter of the nut tightening seating surface on the inner periphery thereof are substantially the same. The size is determined by the contact width. That is, by increasing the contact width, the force for fixing the disc wheel and the axle can be increased. Further, desirably, such a contact width may be set to 1.5 mm or more in consideration of safety.
[0010]
The automobile disc wheel according to the present invention may be used in combination with so-called winter tires such as studless tires and snow tires generally used by users in winter. Since such tires are often used on rough roads such as snowy roads, the tires are subjected to a greater load as compared to normal paved road running. Under such circumstances, if a tire attached to a conventional disc wheel using a different type of nut is used, the disc wheel and the axle are further fixed because the fixing between the disc wheel and the axle becomes insufficient. It is easy to loosen, and there is a possibility that it may lead to breakage and accidents accompanying it. On the other hand, according to the disc wheel of the present invention, the disc wheel and the axle can be properly fixed and held regardless of the type of nut as described above. There is an excellent advantage that a situation that can be disadvantageous to the user can be avoided.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the accompanying drawings.
The steel disc wheel 1 shown in FIGS. 1 and 2 is composed of a rim 2 and a disc 5 having a hub hole 3 in the center. The disc wheel 1 is integrated by fitting a disc 5 on the inner peripheral surface of the rim 2 and joining them by fillet welding or spot welding. For fillet welding, known techniques such as arc welding and laser welding can be used.
[0012]
FIG. 3 shows a disk 5 forming the disk wheel 1. A predetermined wheel cap (not shown) is engaged with the hub hole 3 provided in the center portion in a cap groove 7 formed around a hub hole flange 4 protruding to the front side of the disc wheel 1. A hub mounting surface 10 is provided on the back side of the disc wheel 1 so as to contact the hub when the disc wheel 1 is attached to a hub (not shown) connected to the axle of the automobile using the hub hole 3 as a guide. A plurality of bolt holes 6 that are located radially outside the hub hole 3 around the hub hole 3 and are formed at equal intervals in the circumferential direction are disposed on the hub mounting surface 10.
[0013]
Further, on the front side of the disc wheel 1, a raised portion 8 that protrudes most axially outward in the radial direction of the bolt hole 6, and a plurality of decorative holes 9 that are formed in the circumferential direction outside the raised portion 8. Is provided. The raised portions 8 and the decorative holes 9 play a role of improving design properties, improving rigidity, reducing weight, improving heat dissipation, and the like. Note that the raised portion 8 and the decorative hole 9 may not be provided depending on the type of wheel.
[0014]
Such a steel disc wheel 1 is made of a steel material mainly composed of iron, and is generally formed by adding an alloy element such as Ni, Cr, Si, Mn, or Ti to the steel material. By using such an alloy steel, it is possible to obtain a disc wheel 1 having excellent wear resistance, heat resistance, corrosion resistance, and the like. And the disc wheel 1 is obtained by welding the rim | limb part 2 and the disk 5 which were formed by press molding from such a steel material plate material as mentioned above. Note that the bolt hole 6 and the nut tightening seating surface according to the present invention are formed by the hole forming punch and the die at the same time as the press forming of the disk 5 or after the press forming.
[0015]
Next, attachment of the disc wheel 1 to an automobile will be described.
A hub mounting surface 10 is provided so that a bolt wheel formed on the hub is inserted into the bolt hole 6 with the hub wheel 3 as a guide, with the hub connected to the disc wheel 1 with an appropriate tire attached to the axle of the automobile. Contact the hub. Thereafter, the tape wheel 21 (or spherical nut 22) is fastened to the bolt portion protruding from the bolt hole 6 with a required tightening torque, thereby fixing the disc wheel 1 to the axle. As a result, the tire is properly attached to the automobile.
[0016]
Next, the main part of the present invention will be described.
As shown in FIG. 4, a nut mounting seat surface 13 is formed on the inner peripheral edge of the bolt hole 6 provided in the disc wheel 1. The nut mounting seat surface 13 has a configuration in which a tapered surface 11 is formed on the inner side and a spherical concave surface 12 is formed on the outer side in the inner and outer direction. Since the tapered surface 11 and the spherical concave surface 12 have shapes corresponding to the shapes of the tapered nut 21 and the spherical nut 22, respectively, the tapered surface 11 and the spherical concave surface 12 are formed to have a central axis equal to that of the bolt hole 6.
[0017]
Then, when the taper nut 21 is tightened to the nut tightening seat surface 13, the taper nut 21 is surface-bonded to the taper surface 11 as shown in FIG. On the other hand, when the spherical nut 22 is tightened, the spherical nut 22 and the spherical concave surface 12 are surface-bonded as shown in FIG. Thus, the disc wheel 1 is appropriately fixed and held on the axle by applying a predetermined tightening torque and performing surface pressure bonding.
[0018]
Further, on the nut tightening seat surface 13 formed on the disc wheel 1 in this specific example, a tapered surface 11 formed with a contact width of 1.5 mm, and a spherical concave surface 12 formed with a contact width of 1.9 mm, It has. Here, since the nominal diameter M12 is used as a bolt and nut used in a general automobile, a nut tightening seat surface 13 corresponding to this is formed. Thus, the disc wheel is obtained by press-fitting a nut to which a required tightening torque is applied to each contact surface formed by the average diameter of the nut tightening seat surface 13 that is determined in advance and the contact width. 1 can be fixed to the axle with sufficient force, and the fixing can be maintained for a relatively long time.
[0019]
As described above, in the disk wheel 1 according to the present invention, both the taper nut 21 and the spherical nut 22 can be fixed to the axle with a sufficient force, so that the bolt and the nut are sheared by the force received from the road surface. Even when concentrated stress such as force is applied, the disc wheel 1 and the axle are not easily loosened, and sufficient fixation can be maintained.
[0020]
The present invention is not limited to this embodiment, and can be implemented in various forms without departing from the gist of the present invention. The present invention can be applied not only to a steel disc wheel but also to other disc wheels having a predetermined configuration, such as an aluminum disc wheel.
[0021]
【The invention's effect】
In the present invention, as described above, a tapered surface ( a surface to which a tapered nut is crimped) and a spherical concave surface (a surface to which a spherical nut is crimped) are coupled inward and outward with a nut tightening seating surface of an automobile disc wheel. Since it is configured, when it is tightened using a taper nut, the surface is pressure-bonded to the tapered surface, and when it is tightened with a spherical nut, it is surface-bonded to the spherical concave surface. For this reason, the disc wheel and the axle can be fixed and held with sufficient force regardless of whether the taper nut or the spherical nut is used, and the user can purchase the disc wheel without worrying about the nut shape. In addition, since insufficient tightening of the nut can be reduced from the product surface, there is an advantage that defective mounting between the disc wheel and the axle is reduced.
[0022]
In addition, the tapered surface and the spherical concave surface forming the nut tightening seat surface form a contact width of 1.0 mm or more, so that the disc wheel and the axle are properly fitted when the nut is tightened with a predetermined tightening torque. A force that can be fixed and a holding force that maintains the force can be obtained. As a result, even if an external force such as vibration is applied while the automobile is running, the looseness between the disc wheel and the axle can be prevented for a long period of time, so that safety is maintained.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a steel disc wheel 1 according to the present invention.
FIG. 2 is a plan view of the disc wheel 1. FIG.
FIG. 3 is an oblique view of the disk 5;
FIG. 4 is an enlarged vertical sectional view of a nut tightening seat surface 13;
FIG. 5 is a cross-sectional view illustrating a tightened state of the taper nut 21. FIG.
6 is a cross-sectional view showing a tightened state of a spherical recess 22. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Disc wheel 6 Bolt hole 11 Tapered surface 12 Spherical concave surface 13 Nut clamping seat 21 Tapered nut 1 Spherical nut

Claims (2)

In an automotive disc wheel fixed to an axle by tightening a taper nut or a spherical nut by inserting a bolt portion formed on a hub of an axle into a bolt hole provided on a hub mounting surface,
The nut tightening seating surface formed on the inner peripheral edge of the bolt hole of the disc wheel is formed by coupling an inner tapered surface to which the tapered nut is surface-bonded and an outer spherical concave surface to which the spherical nut is surface-bonded inward and outward. An automobile disc wheel characterized by being a thing . 2. The disk wheel for an automobile according to claim 1 , wherein each of the tapered surface and the spherical concave surface constituting the nut mounting seat surface has a contact width of 1.0 mm or more.

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