JPH06227202A - Light alloy wheel for automobile - Google Patents

Abstract

PURPOSE:To ensure lightweight construction and provision of high stiffness for a piece wheel of light alloy, increase the strength of a disc spoke part, lessen deflective vibration in actual running, and enhance the safety in maneuvering. CONSTITUTION:A nut detention hole 9 is formed in the range of a rim drop part 7 from a rim front bead seat part 6. A bolt detention hole 10 is formed in the disc center part 5. The head 11b of a bolt 11 is detained with the bolt detention hole 10, and the other is fastened by a nut 12 detained with the hole 9, and the bolt 11 is given a tensile force.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light alloy wheel for automobiles.

[0002]

2. Description of the Related Art Conventionally, a light alloy one-piece wheel is composed of a rim 13 and a disc 14 as shown in FIGS. 7 to 10, and the disc 14 is composed of a disc hub portion 16 and a disc spoke portion 15. It is configured.

The disc hub portion 16 is mainly disc-shaped, and the disc spoke portion 15 is provided with various designs. For example, the mesh type shown in FIGS. 7 and 8, the fin type shown in FIGS. 9 and 10 and other disc type, Products with various design features such as spoke type are made.

[0004]

The light alloy one-piece wheel as shown in FIGS. 7 to 10 has the following problems.

Since it is a cast wheel, it is extremely vulnerable to the impact load caused by curb riding and collision in actual running, and therefore, it requires durability performance several times as high as that of a normal wheel road (for example, steel wheel) and its safety. Must be secured.

In particular, the impact load P in the direction of the arrow as shown in FIG. 7 is the most frequent in actual traveling, and in order to withstand the impact, the rim flange portion 17 and the disc spoke portion 15 must have sufficient strength. There must be. As a result, it will be constructed with a thickness several times thicker than that of a normal steel wheel, and the weight reduction effect of the light alloy wheel is not sufficiently exerted.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a light alloy integrally cast (or forged) wheel from a rim front bead seat portion (6) portion to a rim drop portion (7). A nut engaging hole (9) is formed in the range, a bolt engaging hole (10) is formed in the disc center portion (5), and the head of the bolt (11) is formed in the bolt engaging hole (1).
0) and the other end is tightened and held by the nut (12) locked in the nut engaging hole (9), and the bolt (1
A wheel made of a light alloy for automobiles, characterized in that a tensile force is applied to 1).

[0008]

By applying a tensile force to the bolt (11), a compressive prestress is applied to the disk spokes (3) of the wheel, and the attractive force due to the actual load at that portion can be reduced.

[0009]

EXAMPLE A first example of the present invention shown in FIGS. 1 and 2 will be described. 1 is a rim, 2 is a disc, 3 is a disc spoke part, 4 is a disc hub part, 5 is a disc center part, 6 is a bead seat part on the rim front side, 7 is a rim drop part, 8 is a rim flange part, and these are integrated. It is designed as a cast hybrid wheel.

Reference numeral 9 denotes a nut engaging hole penetrating inward and outward in the range from the rim front bead seat portion 6 to the rim drop portion 7, and is formed in a predetermined number at predetermined intervals in the circumferential direction. Further, the outer side portion of the nut engaging hole 9 is countersunk, so that the head of a nut 12 described later is locked.

Numeral 10 is a bolt engagement hole penetrating in the disc center portion 5 inward and outward, and is formed in the same number as the nut engagement holes 9 at a predetermined interval in the circumferential direction.
Further, the inner portion of the bolt engagement hole 10 is counterbored,
The head of the bolt 11 described later is locked.

Reference numeral 11 denotes a bolt, which is a high-strength bolt having a length extending over both the engaging holes 9 and 10 and a tensile strength of about 120 kgf / mm ² . Also, the bolt 1
1, a male screw 11a is formed on the rim front bead seat portion 6 side, and a large diameter head portion 11b is formed on the disc center portion 5 side.

Reference numeral 12 denotes a nut, which is engaged with the nut engaging hole 9 and screwed with the male screw 11a of the bolt 11. The nut 11 is a high tension nut.

To make the wheels shown in FIGS. 1 and 2, first, a one-piece cast (or forged) wheel as shown in FIGS. 3 and 4 is made. In making this wheel, it is important to select a wheel design having a structure that allows the tension of the bolt 11 to be fully utilized. For example, a mesh type as shown in FIGS. 7 and 8 or a wheel type as shown in FIGS. If a disc spoke design of a fin type shape or a design close to that shape is selected, the combination (matching) with the bolt 11 is easy and the effect of the bolt tension described above can be sufficiently exerted.

Next, an engaging hole 10 for accommodating the head of the bolt 11 is formed through the disk center portion 5, and counterbore cutting is performed so that the head of the bolt is seated. Nut 12
A nut engaging hole 9 for accommodating is formed so as to penetrate from the outer peripheral surface side of the rim, and counterbore cutting is performed so that the nut head seats.

After that, coating is performed, the design surfaces A to B are subjected to a gloss finish cutting with a diamond tool (diamond tool), and then clear coating is performed again to complete the integrally cast portion.

Next, as shown in FIGS. 1 and 2, bolts 11 are inserted through the engaging holes 10 in the disk center portion 5 to radially project, and the tips are passed through the nut engaging holes 9 and the nuts 12 are inserted. From the outer peripheral side of the rim, engage the nut seat of the nut engaging hole 9 and tighten the bolt 11.

In this tightening, it is important that the tightening torque of the bolt acts uniformly over the entire circumference, and that the tightening torque is a constant torque that maximizes the effect of strength improvement by the bolt tension. After that, the gap portion of the engagement hole 9 of the nut head is sealed with a sealant to complete the assembly.

FIGS. 5 and 6 show an embodiment in which the present invention is applied to an integrally cast hybrid wheel of a type in which the diameter of the disk center portion 5a is large. Also in this embodiment, the bolt 11 is provided by being tightened similarly to the above.

[0020]

As described above, according to the present invention, a hybrid of a light alloy one-piece wheel and a bolt / nut gives a compression prestress to the disc spokes of a cast wheel having excellent compressive strength, and its portion. The tensile stress due to the actual load can be reduced and the strength can be improved. Therefore, it is possible to secure a lightweight and high rigidity that cannot be obtained only with the light alloy one-piece wheel, the above-mentioned conventional problems are solved, and further, the unsprung weight is reduced, and the high rigidity particularly in actual running It is possible to provide a light alloy wheel which has less runout vibration during high-speed traveling and has excellent steering stability and which is comfortable to ride.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view showing an embodiment of an integrally cast hybrid wheel according to the present invention.

FIG. 2 is a front view of the same.

FIG. 3 is a vertical sectional side view showing an integrally cast wheel used in the embodiment of FIG.

FIG. 4 is a front view of the same.

FIG. 5 is a vertical sectional side view showing another embodiment of the present invention.

FIG. 6 is a surface view of the same.

FIG. 7 is a vertical cross-sectional side view showing an example of a mesh type one-piece aluminum wheel having a conventional structure.

FIG. 8 is a front view of the same.

FIG. 9 is a fin-type one-piece structure in a conventional structure.
The longitudinal side view which shows an example of an aluminum wheel.

FIG. 10 is a front view of the same.

[Explanation of symbols]

 5 Disc center part 6 Rim front bead seat part 7 Rim drop part 9 Nut engaging hole 10 Bolt engaging hole 11 Bolt 12 Nut

Claims (1)

[Claims] 1. A disc center is formed by penetrating a nut engaging hole (9) in a range from a rim front bead seat portion (6) portion to a rim drop portion (7) of a light alloy integrally cast (or forged) wheel. A bolt engaging hole (10) is formed through the portion (5), and the head of the bolt (11) is attached to the bolt engaging hole (1).
0) and the other end is tightened and held by the nut (12) locked in the nut engaging hole (9), and the bolt (1
A wheel made of a light alloy for automobiles, characterized in that a tensile force is applied to 1).