JPS6134916B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in welding methods for automotive foil rings, head lamp rims, and other decorative metal plate products.

The welding method of the present invention is intended to facilitate the finishing of the front side of the welded part and to provide a highly decorative and beautiful metal plate product without leaving any weld marks. Place both edges to be welded on the front side of the product over the groove of the backing metal, which has a contact surface that matches the shape of the product surface and has a groove that is continuously recessed along the weld line in the contact surface. The welding torch is moved from the welding start end to the welding end end of the welding line on the back side of the product, and the molten metal of the welding line is By causing the metal plate to hang down slightly in the groove, a protruding strip having a height of about a fraction of the thickness of the metal plate to be welded is formed on the front surface of the product, and the product Welding is performed by forming grooves corresponding to the protrusions on the back side of the weld, and further,
It is characterized in that the protruding stripes protruded as described above are finished smooth so that they are flush with the non-welded portion of the front side of the product.

Hereinafter, details of the present invention will be explained based on the accompanying drawings.

The attached drawings show an embodiment of the manufacturing process of the automotive foil ring 1. As shown in the cross-sectional shape and side profile in FIG. It has a small-diameter annular inner peripheral edge 12, and the inner end edge is formed into a U-shaped inner folded edge 13. On the other hand, the outer circumferential edge (generally designated by reference numeral 14) that engages with the road wheel continues from an outwardly-opening outward annular edge 15 to a large-diameter inward annular edge 16 bent in an F-shape. The edges are turned inward and formed into edges 17.

In the first step, as shown in FIG. 2, an intermediate annular material shaped like two foil rings symmetrically joined together, that is, an object to be welded material 3 to be welded in this invention is produced.

FIG. 1 shows an apparatus for forming a workpiece 3 from a metal strip W, and a group of forming apparatuses, designated as a whole by reference numeral 2, supports and supplies the metal strip W wound into a roll. supply device 21,
It includes a material feed roller 22, a press device 23, a roll forming device 24, and a coiling machine 25.

As described above, the metal strip W has a width twice the width of the cross-sectional shape of the foil ring 1 developed in a plane. The wide strip W is subjected to pretreatment such as removing curls from being wound into a roll in a press device 23, and is also pre-notched 4 to serve as a standard for later cutting into a predetermined length.

The strip W exiting the press device 23 is formed into a predetermined cross-sectional shape by a roll forming device 24 consisting of a combination of forming rolls in multiple stages. It is symmetrical about the center line (FIG. 2 C-C).

The strip W formed into a linear material with a predetermined cross-sectional shape by the roll forming device is introduced into a coiling machine 25, where it is passed through a guide device 2 having a guide surface of a predetermined curvature.
6 into an annular or continuous coil shape, and cut with a cutting device (not shown) using the notch 4 formed in the pre-notching process as a reference,
An intermediate annular material having the same shape as the foil ring 1 (FIGS. 2 to 4), that is, an object to be welded 3 which is a material in the present invention is made.

The foil ring 1, which is the final product, has the above-mentioned U-shaped inner folded edge 13 on the annular inner circumferential edge 12, and has an inward annular edge 16 and an inward folded edge 17 on the outer circumferential edge 14. , these shapes are not suitable for the next welding process. Therefore, in manufacturing the intermediate annular material, these are formed into the shape of the central flat plate part 31 which is still unfolded into a flat plate shape, and the outer flat plate part 34 which has an outwardly opening flat plate-like cross section. The intermediate flat plate portion 33 will later become the ring body 11 of the foil ring, and the oblique flat plate portion 32 will later become the annular inner peripheral edge 12.

Further, referring to FIG. 3, the radius of curvature r at the bent portion between the central flat plate portion 31 and the oblique flat plate portion 32 and other bent portions between each plate portion is set to 3 mm or more in order to obtain a good welding result. .

The intermediate annular material 3 of this embodiment is an intermediate product whose cross-sectional shape is similar to the product cross-sectional shape as described above, but if the final product has a simple cross-sectional shape, it is necessary to Needless to say, it should have a cross-sectional shape.

The intermediate annular material 3 is formed into an intermediate annular body 3' by welding the cut ends 30 facing each other in a butted manner.

The foil ring 1 is attached to the inner peripheral surface 1 of the annular body during use.
A becomes the front side, and the outer circumferential surface 1b becomes the back side.
In the welding method of this invention, the front side of the product is pressed against the backing metal of the welding device, the back side of the product is known, and welding flame is sprayed along the weld line. A concave groove is formed in the backing metal along the welding line so that it does not come into contact with the object to be welded.

Figures 5 and 6 are shown enlarged as a whole.
In the figure, 5 indicates a welding nozzle (torch) of a plasma arc welding device, 51 is a plasma working gas inlet, 52 is a shielding gas inlet, 53 and 54 are a coolant inlet and its discharge port, and 55 is a plasma arc welding device. There are 50 spouts.

The backing metal 6 is usually made of chromium copper, and its contact surface 60 conforms to the cross-sectional shape of the inner circumferential surface of the metal plate workpiece 3 (FIG. 6) and the annular shape of the workpiece 3 to be welded. It has an arcuate shape (FIG. 5) along the inner peripheral surface. The contact surface 60 has a concave groove 61 along the welding line of the workpiece 3 (the line where the opposite edges 30, 30 face each other) of the workpiece 3 over a certain width to avoid contact with the workpiece 3. It is provided along the entire length of the line.

In FIG. 6, the inner circumferential surface 3a (the front side of the product) of the workpiece 3 (the welding edge 30 is shown with diagonal lines) is brought into close contact with the contact surface 60 of the backing metal 6, and both edges 30,
30 are set on the concave groove 61 facing each other, and the torch 5 is moved in the direction of the arrow from one end of the welding line along the welding line to perform copy welding.

In the above-mentioned welding, the backing metal 6 does not contact the constant width portion of the workpiece 3 along the weld line. Therefore, there is an advantage that the heat of the welded part is not absorbed by the backing metal 6. And the outer peripheral surface 3 of the metal plate workpiece 3
The raw metal melted by the welding flame injected from b slightly hangs into the groove 61, and a protruding strip 3c is formed on the inner circumferential surface 3a, which is the front side of the product, and on the outer circumferential surface 3b, which is the back side of the product. A groove 3d is formed. The protruding height t of the protruding strip 3c is set to about a fraction of the strip thickness so that the protruding strip 3c can be easily removed in a subsequent process.

In the product which has been welded as described above, as shown in FIG. 7, it is possible to grind and polish the protrusions 3c that are formed on the surface of the product. is easily removed. Therefore, burrs and the like caused by welding are completely removed at the same time, and a smooth surface 3e with almost no welding marks left can be obtained. There will be a concave groove 3d on the back side of the product, but since it will not be visible to the public from the surface side when the product is made, there is no problem with it. Even when molding, since there are no convex portions, there is no problem with processing.

The intermediate annular body 3' produced in the above welding process is
The annular body is cut along the center line C--C perpendicular to the axis of the annular body to form two identical intermediate products 1' or a finished product (in the case of the embodiment, an intermediate product).

FIGS. 8 and 9 show an example of a cutting device for the intermediate annular body 3', and the cutting device 7 includes a guide and drive roller 71 that rotates in contact with the inner circumference of the annular body,
A cutting blade 72 that can move forward and backward along the center line C-C.
It consists of a cutter 73 having a

When the cutter 73 is pressed against the center of the intermediate annular body 3' while rotating the guide/driving roller 71 as shown in FIG. disconnected.

Since the intermediate product 1' is formed to have an intermediate cross-sectional shape as described above, the outer circumferential edge 14, the inner folded edge 13 of the annular inner circumferential edge, etc. are finished.

These final finishing processes can be easily performed by known press working and roll forming processes, so a detailed explanation will be omitted, but FIG. This is an example of a press apparatus for forming. In the press device 8 shown in FIG. 10, 81 is a receiving mold, 82 is a pressing mold, and 16' is an outer flat plate part 34 of the intermediate product 1'.
A portion corresponding to the inward annular edge 16 and 17' formed by bending the inward folded edge 17 indicates a pre-bent edge of the inward folded edge 17.

According to the welding method for decorative metal plate products of the present invention as described above, not only can the front side of the joint be easily finished, but also beautiful metal plate products with high decorativeness can be produced without leaving almost any welding marks. It is effective in providing the following. Moreover, since the product obtained by the present invention only has concave grooves instead of convex portions on the back surface, even if press processing is performed in the post-process,
To make a final product extremely highly decorative without causing dents or the like on the surface side.

[Brief explanation of the drawing]

FIG. 1 is a side view of an apparatus for forming a workpiece to be welded according to the present invention from a metal strip;
Figure 2 is an enlarged sectional view of the object to be welded (taken along the line in Figure 4), Figure 3 is an enlarged perspective view of all its fragments,
FIG. 4 is a front view thereof, FIG. 5 is a longitudinal sectional front view of the welding device showing the backing metal in cross section along the line in FIG. 6, and the welding nozzle in cross section, and FIG.
7a and 7b are enlarged sectional views showing the welded portion of the intermediate annular body before and after finishing, respectively. FIG. 8 is a side view of the cutting device, and FIG. 9 is a partial view. FIG. 8 is an enlarged plan view showing a section taken along the line in FIG. 8, FIG. 10 is a vertical partial side view showing an example of the final finishing device, and FIG. . 3=Metal plate to be welded, 3c=Protruding part, 30=
Edge to be welded, 5 = welding torch, 6 = backing metal, 60
= contact surface, 61 = concave groove.

Claims (1)

[Claims] 1 Both edges to be welded 3 of decorative metal plate to be welded 3
0,30 on the contact surface 6 that conforms to the shape of the product surface.
0 and has a groove 61 continuously recessed along the welding line in the corresponding contact surface 60 of the backing metal 6.
1, the surface 3a that becomes the front side of the product is the contact surface 6.
The welding torch 5 is moved from the welding start end to the welding end end of the welding line on the back surface 3b of the product, and the molten metal of the welding line is transferred to the groove 61. By letting the product hang down a little continuously, a protruding strip 3c having a height t of about a fraction of the thickness of the metal plate to be welded 3 is formed on the surface 3a that becomes the front side of the product, and the product Welding is performed by forming grooves 3d corresponding to the protrusions 3c on the surface 3b that will be the back side of the product, and furthermore, the protrusions 3c that have been made to protrude as described above are welded to the non-concave surface 3a that will be the front side of the product. A method for welding decorative metal plate products, which is characterized by smooth finishing so that it is flush with the welded part.