JPH0999701A - Fastening structure of vehicular wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it hard for a vehicular wheel to be loosen against external force. SOLUTION: A fastening hole 14 is board in a disk part 12 of a vehicular wheel 10, and a taper nut 16 is inserted. A contact surface 17 of the taper nut 16 is formed so as to gradually become a small diameter at a first angle θ1. A nut contact surface 18 of the fastening hole 14 is formed so as to gradually become a small diameter at a second angle θ2 smaller than the first angle θ1 from a nut inserting side end part 18A, and in a condition of having a tolerance, (θ1>θ2) is realized. A bolt 20 is inserted into the fastening hole 14, and the bolt 20 is pressed in and fixed to a through hole 24 bored in a hub 22 on the vehicle side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fastening structure for a vehicle wheel such as an automobile, and more particularly to a fastening structure for a vehicle wheel having a disc portion formed with a fastening hole.

[0002]

2. Description of the Related Art Conventionally, as an example of a vehicle wheel fastening structure in which fastening holes are formed in a disc portion, Japanese Patent Application Laid-Open No. HEI-1 is proposed.
The structure shown in Japanese Patent Laid-Open No. 109101 is known.

As shown in FIG. 3, in this vehicle wheel fastening structure, the nut contact surface 72A of the fastening hole 72 is formed in the fastening hole 72 in the vehicle wheel 74 in which the fastening hole 72 is formed in the disk portion 70. It is formed by a curved surface protruding toward the axis 76 of 72. As a result, the contact portion P1 between the nut 80 and the nut contact surface 72A, which is shown in phantom in FIG. 3, has a complete circumferential shape, which enables uniform torque transmission and helps to reinforce the disk portion 70. In addition, the area of the contact portion P1 is increased when the nut 80 is tightened further.

[0004]

However, in such a vehicle wheel fastening structure, the vehicle wheel 74 has a curved nut contact surface 72A,
Since it comes into contact with the nut 80, depending on the processing accuracy, the contact portion P
1 is the direction of the small diameter side of the fastening hole 72 (direction of arrow Y in FIG. 3)
It may shift to When the contact portion P1 shifts in the direction of the arrow Y, the distance L between the axis line 76 of the fastening hole 72 and the contact portion P1.
1, that is, the equivalent circle diameter R of the joining surface for fastening becomes small,
The fastening structure makes it easy to loosen against external force (moment input in the loosening direction).

In view of the above facts, an object of the present invention is to obtain a vehicle wheel fastening structure that is not easily loosened by an external force.

[0006]

According to a first aspect of the present invention, there is provided a fastening structure for a vehicle wheel according to the present invention, wherein a nut is formed so as to have a gradually smaller diameter at a first angle, and the first side from the nut insertion side. And a fastening hole formed in the vehicle wheel such that the diameter is gradually reduced at a second angle smaller than the above angle, and the fastening is performed when the nut is fastened to a bolt fixed to the vehicle side. It is characterized in that the contact surface with the working hole starts to contact from the end portion of the fastening hole on the nut insertion side.

As described above, since the nut is formed at an angle larger than the forming angle of the fastening hole, when the nut is fastened to the bolt fixed to the vehicle side, the contact surface of the nut is the wheel. The large diameter side of the fastening hole formed in
That is, the contact starts from the end portion on the nut insertion side.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a vehicle wheel fastening structure of the present invention will be described with reference to FIGS.

As shown in FIG. 1, a vehicle wheel 10 of this embodiment is made of an aluminum alloy material, and a disc portion 12 has a fastening hole 14 formed therein. The taper nut 16 is inserted.

The contact surface 17 of the taper nut 16 is formed so as to have a gradually smaller diameter at a first angle θ1, and the first angle θ1 is, for example, 6 when there is a tolerance.
It is 0 ° to 61 °.

On the other hand, the nut contact surface 18 of the fastening hole 14
Is formed such that the diameter gradually decreases from the nut insertion side end portion (upper end portion in FIG. 1) 18A at a second angle θ2 that is smaller than the first angle θ1, for example, the second angle. θ2 is 59 ° to 60 ° in a state where there is a tolerance.

That is, in the state of having the tolerance, θ1>
It is θ2. A bolt 20 is inserted into the fastening hole 14 from the lower side of FIG. 1, and a taper nut 16 is screwed into the bolt 20. Bolt 20
It is press-fitted and fixed in a through hole 24 formed in the vehicle-side hub 22 by serration fitting.

Next, the operation of this embodiment will be described. In the vehicle wheel 10 of the present embodiment, when the taper nut 16 is fastened to the bolt 20 fixed to the hub 22 on the vehicle side, θ1> θ2 as shown in FIG. The contact portion P with 12 always starts from the large diameter side end portion 18A of the fastening hole 14, and as the taper nut 16 is tightened, the wheel side 10 is plastically deformed to form a contact surface.

Therefore, the distance L between the axis 14A of the fastening hole 14 and the contact portion P is larger than that when the contact portion P1 is on the smaller diameter side of the fastening hole as shown in FIG. Therefore, the taper nut 16 is unlikely to loosen with respect to an external force (a moment input in a direction in which the taper nut 16 loosens).

In the vehicle wheel 10 of this embodiment, since the nut contact surface 18 is not a curved surface, the fastening hole 14
Can be processed by drilling. Therefore, NC
Compared with a nut contact surface that has to be curved, which requires machining, machining is easier and cost can be reduced.

In the above, the present invention has been described in detail with respect to specific embodiments, but the present invention is not limited to such embodiments, and various other embodiments within the scope of the present invention. It is obvious to a person skilled in the art that

For example, not only an aluminum wheel but also a magnesium wheel such as a magnesium wheel that is plastically deformed to secure the surface contact between the nut and the wheel can be applied.

[0018]

According to the fastening structure for a vehicle wheel of the present invention as set forth in claim 1, the nut is formed so as to have a gradually smaller diameter at the first angle, and is smaller than the first angle from the nut insertion side. When the nut is fastened to a bolt fixed to the vehicle side, the contact surface with the fastening hole has a fastening hole formed in the vehicle wheel such that the diameter gradually becomes smaller at the second angle. Since it is configured to start contacting from the end of the fastening hole on the nut insertion side, it has an excellent effect that it is difficult to loosen due to external force.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a fastening structure for a vehicle wheel according to an embodiment of the present invention.

FIG. 2 is an operation explanatory view of the vehicle wheel fastening structure according to the embodiment of the present invention.

FIG. 3 is a side sectional view showing a vehicle wheel fastening structure according to a conventional embodiment.

[Explanation of symbols]

 10 Vehicle Wheel 12 Disk Part 14 Fastening Hole 16 Taper Nut 17 Contact Surface 18 Nut Contact Surface 18A Nut Insert Side 20 Bolt 22 Hub

Claims (1)

[Claims] 1. A nut formed to have a diameter that gradually decreases at a first angle, and a vehicle wheel that has a diameter that gradually decreases from a nut insertion side at a second angle that is smaller than the first angle. When fastening the nut to a bolt fixed to the vehicle side, the contact surface with the fastening hole contacts from the nut insertion side end of the fastening hole. Vehicle wheel fastening structure characterized by starting.