JPS60180733A - Cut-machining method for aluminum wheel - Google Patents

Abstract

PURPOSE:To secure the paint film thickness of corner sections and obtain corrosion resistance by forming an R-section with the radius of curvature of 0.5mm. or more at corner sections of a wheel and cutting up to the cut-machining line on the tangential line of the R-section. CONSTITUTION:Corner sections 13, 13 of a spoke 11 are formed into an R-section with the radius of curvature R of 0.5mm. or more by casting, and a cut margin 17 of 0.5mm. or more is provided in advance on the tangential line of the corner sections 13, 13 via a cut-machining line 15. The surface of the spoke 11 thus formed is cut with a cutting tool, and the cut margin 17 is cut out up to the cut- machining line, then a cut finish surface 19 continued to the unground corner sections 13, 13 is formed. Next, the surface of the spoke 11 is applied with clear coating and is heat-treated, then a uniform paint film 23 is formed over the side surface 21 of the spoke 11, the corner sections 13, 13 and the cut finish surface 19, and the paint film of 0.5mum or more sufficient for corrosion resistance can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for cutting aluminum wheels for vehicles.

BACKGROUND OF THE INVENTION Aluminum wheels, which are made entirely of aluminum, are becoming popular among wheels that are attached to the axle of automobiles. This aluminum wheel is shaped by casting, and the surface of the aluminum wheel is machined to give it a metallic luster. Therefore, the surface is beautifully finished and exhibits a design effect. Furthermore, in order to maintain these effects over a long period of time and to improve rust prevention, the cut surface of the aluminum wheel is coated with a clear coating.

FIG. 1 shows an aluminum wheel body, and a rim 5 is integrally provided on this body 1 with spokes 3 interposed therebetween. By the way, when the spoke 3 is enlarged in cross section, it is formed as shown in FIG. In other words, (4) is made of cast aluminum, cut by cutting @ 6i, and then clear coated. However, as a result of the above cutting process, the corner portions 7° 7 of the spokes 3 become a nip, and as shown in (B), even if clear coating is applied, the necessary coating film 9 cannot be secured on the corner portions 7, 7. Generally, a coating film 9 with a thickness of 5 μm or more is required to obtain anti-rust properties, but due to heat treatment after painting, the coating film 9 on the corner portions 7, 7 is approximately μm thick.
Rust occurs starting from point 7, reducing the decorative effect.

This invention was made in view of the above circumstances, and its purpose is to form a radius of curvature of 0.5 mm or more at the corner of an aluminum wheel, and to form a radius on the tangent of the radius of 0.5 mm. The purpose of this paper is to provide a cutting method for aluminum wheels that can ensure a sufficient coating thickness even at the corners by cutting up to the located cutting line, thereby providing anti-rust properties.

The present invention will be described below based on an embodiment shown in the drawings.

FIGS. 3A, 3B, and 3C show the cutting process of an aluminum wheel, and 11' shows a cross section of a spoke of the aluminum wheel. This aluminum wheel is shaped by casting, and the spokes are cast or colored. As shown in (6), the corner portion 13.13 of the spoke 11 is formed into a rounded portion with a radius of curvature (R) of 0.5 or more by casting, and a cutting line is placed on the tangent of this corner portion 13.13. A cutting allowance 17 of 0.5 m or more is provided in advance through the spoke 15. The surface of the spoke 1 thus formed is cut with a cutting tool, and the cutting allowance 17 is shaved down to the cutting line 15. Then, as shown in (B), a cut finished surface (19) is formed that is continuous with the unground corner portion 13°13.

Next, a clear coating is applied to the surface of the spoke 1) and heat-treated. As shown in (C), a uniform coating film is formed over the side surface 21, the corner portions 13, 13, and the cut surface 19 of the spoke 1. 23 is formed, and its film thickness can be ensured to be 5 μm or more, which is sufficient to obtain antirust properties.

According to the inventor's experiments, the radius of curvature (R
) is less than 0.5 mm, the film thickness of the corner part 13 becomes thinner due to the heat treatment after painting, and it is not possible to ensure a film thickness of 5 μm or more, but if the radius of curvature (R) of the corner part 13 is 0.5 r As a result, a film thickness of 5 μm or more could be ensured even after heat treatment after painting.

In addition, in the above-mentioned example, the aluminum wheel spring?
Although we have described the corner part of the aluminum wheel body, any corner part of the aluminum wheel body may be used, and the ventilation holes and rim of the wheel can also be machined in the same manner.

As explained above, according to the present invention, a radius of curvature of 0.5 sun or more is formed at the corner of an aluminum wheel, and cutting is performed to the cutting line located on the tangent of this radius. , a sufficient coating thickness can be ensured even in the corner areas.

Therefore, it exhibits anti-rust power even after long-term use.
The effect is that it is possible to obtain aluminum wheels that are beautiful and have a beautiful design.

[Brief explanation of drawings]

Figure 1 is a front view of the aluminum wheel, Figure 2 (N (B) is a cross-sectional view showing the conventional cutting method, Figure 3 (A) (B)
(C) is a sectional view showing one embodiment of the cutting method of the present invention. 1. Nose torn (part of aluminum wheel), 13.
... Corner part, 15... Cutting line.

Claims (1)

[Claims] In a cutting method in which the surface of an aluminum wheel obtained by casting is finished by cutting, a cutting allowance is provided in advance on the cutting surface of the aluminum wheel to form a rounded part with a radius of curvature (R) of 05 or more at the corner part. This aluminum wheel cutting method is characterized by cutting to the cutting line located on the tangent of this rounded part.