JPH028802Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a resin center cap that covers the center portion of a wheel disk.

2. Description of the Related Art Conventionally, wheel caps covering the entire surface of the wheel have been attached to wheel discs of wheels of automobiles, etc., mainly for decorative purposes. However, due to recent resource and energy shortages, and increases in safety and pollution control costs, the overall cost of vehicles has been reduced.
There is also a growing trend for wheel caps to be decorated only in the center of the wheel disc. In view of these trends, the present invention utilizes the processability of resin to improve decorativeness, simplify the structure and reduce costs, and solve the problem of rotation during rotation with conventional resin center caps. The present invention provides a resin center cap that prevents it from coming off due to vibration or impact.

[Conventional technology]

Hitherto, as this type of center cap, the one disclosed in Utility Model Application Publication No. 52-79630 has been known, and its mounting structure is as shown in Fig. 1. A plurality of locking claws 8 are provided, and a wheel disc 1 is provided at the tip of the locking claw 8.
so as to be able to fit into the end face of the central opening edge 12 of 1,
An annular groove 13 was provided on the outer surface of the locking pawl.

When attaching this resin center cap, the annular groove 13 of the locking pawl 8 was fitted into the end face of the central opening edge 12 of the wheel disc.

[The problem that the idea aims to solve]

However, in this case, a problem occurred in that stress concentration occurred in the locking pawl 8.

That is, the locking claw 8 utilizes the elastic force of the resin molded product, but since the elastic force is generated in a limited range of the root portion 9 of the locking claw, stress is generated at the root portion. It was easy to concentrate, and the locking claws were damaged from the base due to changes over time, and were also damaged due to vibration and impact during rotation, resulting in problems with reliability in terms of mounting strength.

In particular, when the center cap heats up due to heat transfer while driving, or conversely under conditions in a cold region, stress concentration and fatigue accelerating conditions such as heating and cooling are added, which increases the mounting strength. There were particular problems with reliability.

The present invention solves the problem of lack of reliability during installation that conventional resin center caps had, and provides a resin center cap that is suitable for mass production and has less variation in quality.

[Means to solve the problem]

The resin center cap of the present invention is made of resin and is composed of a top plate 1 and a cylindrical side wall 2 connected to the top plate 1, in which the top plate 1 is a thick and rigid structure. At the same time, the surrounding side wall 2 has a thin and flexible structure, and a plurality of closely spaced grooves are provided inside the opening edge of the side wall for fitting and fixing into an annular groove 13 provided on the outer periphery of the central opening edge 12 of the wheel disc. At least three parallel hook-shaped protrusions 3 are provided as one protrusion group 4, and the protrusions 3, except for the positions of the protrusions, come into elastic contact with the inner surface of the central opening edge 12 of the wheel disc. As shown, an arc-shaped standing wall 5 is integrally provided a certain distance inside the inner surface of the side wall 2 from the inner wall of the top plate to the edge of the opening, and on the outside of the tip of this standing wall, the diameter decreases toward the tip over the entire arc. The inclined portion 6 is formed so as to be as follows.

Further, the above-mentioned arc-shaped standing wall 5 has at least the outer surface of both ends thereof, and when the hook-shaped protrusion 3 is fitted into the annular groove 13 of the wheel disk when the cap is attached, it comes into contact with the center opening edge of the wheel disk. Ribs 7 are integrally provided.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 2 to 4.

The resin center cap of this invention is molded from 6-nylon resin containing glass fiber, and the top plate 1
is formed with a wall thickness of 2 mm and has a rigid structure.
Further, the peripheral side wall 2 connected thereto is formed to have a thickness of 1.2 mm and has a flexible structure. On the inside of the opening edge of the side wall 2, three groups of protrusions 4 are provided for fitting and fixing into an annular groove 13 provided on the outer periphery of the central opening edge 12 of the wheel disc. In this case, five hook-shaped protrusions 3, each having a thickness approximately equal to that of the side wall, are provided in parallel at intervals of 2 mm.

In addition, the standing wall 5 is, as shown in FIGS. 3 to 5,
Excluding the position of the group of protrusions, it hangs in an arc shape from the inner wall of the top plate to the opening edge a certain distance inward from the inner surface of the side wall 2 so as to elastically abut the inner surface of the central opening edge 12 of the wheel disk. It is installed integrally with the top plate. On the outside of the tip of this standing wall, an inclined portion 6 is provided slightly below the protrusion 3 so that the diameter decreases toward the tip over the entire arc.

Moreover, the central opening edge 12 of the wheel disc is
Unlike conventional products in which the tip of the cylindrical part is bent toward the inner circumference, it has a simple cylindrical shape.
Its upper end is straight, and an annular groove 13 is formed on the outer periphery of the central opening edge 12.

Therefore, when attaching the resin center cap of the present invention to the central opening edge 12 of the wheel disk 11, the cap must be pushed in between the sloped portion 6 and the lower end of the protrusion 3 so as to straddle the opening edge of the wheel disk. This allows for smooth installation.

Furthermore, in the resin center cap of the present invention, by sandwiching the central opening edge 12 of the wheel disc between the standing wall 5 and the protrusion 3, the protrusion 3 is located at the center opening edge of the wheel disc at all locations.
It can be firmly fitted into the annular groove 13 provided on the outer periphery of 2.

Further, the vertical wall 5 is provided with ribs 7 on the outer surfaces of both ends thereof, which come into contact with the center opening edge of the wheel disk when the hook-shaped protrusion 3 is fitted into the annular groove 13 of the wheel disk when the cap is attached. When the center cap is attached to the wheel disk with its lower end 7' as abutment, the center opening edge 12 of the wheel disk comes into contact with the lower end 7' of the rib 7 and is prevented from going further inside. ing.

[Effect of invention]

(a) This center cap has a top plate part 1 with a rigid structure and a peripheral side wall 2 connected to it with a flexible structure, so the entire cylindrical part of the side wall becomes an elastic body, and the center opening edge 12 of the wheel disc When the protrusion 3 crosses over the opening edge 12, the side wall 2 deforms and bends into a triangular shape close to a circle with the protrusion group 4 as the apex, and the protrusion 3 crosses the groove 13 on the outside of the opening edge 12. When it enters, it returns to its original shape. Since the elastic force at this time is generated in the entire side wall 2, it is possible to solve the problem of stress concentration in a limited range at the base, which is the problem in the conventional example.

(b) Since a plurality of protrusions 3 form a group, and this group is provided at three locations on the circumference of the side wall 2, stress concentration on one protrusion can be prevented, and each protrusion Since a large number of parts are provided at equal intervals and have approximately the same thickness as the side wall, it is possible to prevent sink marks on the external surface, which are a problem in resin molding.

(c) Because of the above features, the inventor confirmed that the thermal shock test, which is used to evaluate the reliability of center caps, etc. We were also able to obtain better performance than conventional products in tests to confirm the following:

〔effect〕

As can be easily understood from the above explanation, the center cap according to the present invention utilizes the elasticity of the resin and is obtained by integral molding, and its cylindrical side shape can disperse stress concentration. Its practical effects are extremely large.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing a conventional resin center cap attached to a wheel disc.
FIG. 2 is an external perspective view of the resin center cap of the present invention. Figure 3 is a bottom view of the resin center cap of the present invention. FIG. 4 is a sectional view taken along the line AA in FIG. 3. FIG. 5 is a partially enlarged sectional view of the resin center cap of the present invention attached to a disc wheel. 1...Top plate, 2...Side wall, 3...Protrusion, 4...
...Protrusion group, 5... Vertical wall, 6... Inclined portion, 7... Rib, 7'... Lower end of rib, 8... Locking claw, 9...
... Root part, 11 ... Wheel disc, 12 ...
Center opening edge, 13... annular groove, 14... opening.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a resin center cap that is molded from resin and is composed of a top plate 1 and a cylindrical side wall 2 connected to the top plate 1, the top plate 1 is a thick rigid structure. At the same time, the surrounding side wall 2 is made of a thin and flexible structure, and a tight shape is formed on the inner side of the opening edge of the side wall for fitting and fixing into an annular groove 13 provided on the outer periphery of the central opening edge 12 of the wheel disc. A plurality of hook-shaped protrusions 3 provided in parallel are provided at at least three locations as one protrusion group 4, and elastically attached to the inner surface of the central opening edge 12 of the wheel disc, excluding the positions of the protrusion group. An arc-shaped standing wall 5 is integrally provided a certain distance inside the inner surface of the side wall 2 from the inner wall of the top plate to the edge of the opening so as to be in contact with the inner surface of the side wall 2. A resin center cap characterized in that an inclined portion 6 is formed so that the angle is small. (2) An arc-shaped vertical wall 5 extending from the inner surface of the side wall 2 to the opening edge, except for the position of the protrusion group 4, has a hook-shaped protrusion 3 on the outer surface of at least both ends thereof, and a hook-shaped protrusion 3 is attached to the annular shape of the wheel disk. Groove 1
3. A resin center cap according to claim 1, which is integrally provided with a rib 7 that comes into contact with the central opening edge of the wheel disk when fitted to the center cap.