JPH0149574B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a trim ring for a foil, and particularly to a method for manufacturing a trim ring by forming a metal plate into an annular shape, welding both ends, and pressing.

[Conventional technology]

9 and 10 are cross-sectional views showing an example of a conventional foil trim ring. The foil trim ring 1 includes a synthetic resin disk-shaped foil cover 2.
It is integrated into the outer periphery and protects this outer periphery. The foil cover 2 is attached to the foil rim 3 via attachment means (not shown).

The foil trim ring 1 faces the outer circumferential surface 4 of the foil cover 2, has a bent piece 6 formed on the inner circumferential side that fits into the recess 5, and has a cover 2 on the outer circumferential side.
The trim ring is integrated with the cover 2 by the bent piece 6 and the bent part 7.

[Problem that the invention seeks to solve]

As shown in FIG.
is welded to form an annular body 10, which is then preformed.
When done from a to the opposite end 9b, the end 9
The heat during welding is concentrated on a and 9b, which tends to melt and cause a welding part S. Therefore, both edges 6a and 7a are bent using a press, and the bent pieces 6 and 9b are bent. When the bent portion 7 is formed, if the burn-through portion S is deep, a part of the burn-through portion S will be exposed in appearance as shown in FIG. 9, resulting in poor appearance and loss of commercial value.

Therefore, the present invention is intended to prevent the defective portion that occurs at the butted and welded ends from appearing visually.

[Means for solving problems]

The present invention is to form a ring-shaped body by welding the abutted parts, leaving both ends of the butted parts, and then bending both ends of the ring-shaped body, including the non-welded parts at both ends, inward to form a trim ring for foil. be.

〔Example〕

First, as shown in Fig. 1, strip material 20 such as a long stainless steel plate with a constant width is stacked several times in the width direction, and after being bent and formed in the width direction according to a constant curvature, one piece is formed. Each piece is cut to form an intermediate material 21 shown in FIG. Next, the cut ends are abutted against each other and the abutted portions 22 are welded as shown in FIGS. 3a and 3b.

During welding, a narrow groove 2 is formed in the center and width direction of the lower electrode 23 made of copper, tungsten alloy, etc.
4, the abutting portion 22 is positioned, and one end 22a of the abutting portion 22 is formed in a horizontal recess 23c formed in the rising wall portion 23b of the side electrode 23a.
and thereby the end portion 22a is fitted into the covering portion 2.
Cover with 3d. The length l of the end portion covered by this covering portion 23d is approximately 0.5 mm. Note that the side electrode 2
3 a rises from the side of the lower electrode 23 in the upper direction of the lower electrode 23 and is electrically integrated with the lower electrode 23 .

Next, an arc is generated from the covering portion 23d of the side electrode 23, and is caused to scan in the opposite direction along the abutting portion 22. Arc is terminal 2 on the opposite side
Stop at a position approximately 0.5mm from 2f. As a result, welding is performed leaving 0.5 mm at the end of the abutted portion, resulting in an annular body. Next, after grinding and polishing the welded part as necessary, both edges 22h, 22h of the annular body including the non-welded part 22e are bent inward as shown in FIG. With the piece 6 fitted into the recess 5 of the foil cover 2, the outer peripheral end is bent toward the back surface of the foil cover 2 to form a bent part 7, integrated with the foil cover, and attached to the foil rim 3. .

According to the above method, both edges including the non-welded portion 22e are bent inward, so that the non-welded portion 22e is not visible in appearance. That is, according to the present invention, the length of the non-welded portion 22e is set to 0.5, for example.
It can be set in advance to about 0.5 mm, so both edges can be bent inward using the center as a fulcrum from this 0.5 mm position. If the depth of the burn-through part S differs for each product as in the past, it is difficult to set the length of the part to be bent, and if this length is short, the burn-through part S will be visible in appearance. The present invention can improve the appearance of all products.

In the present invention, the foil trim ring used integrally with the outer periphery of the foil cover 2 has been described, but the present invention is not limited to this.
As shown in FIG. 8, the present invention can also be applied to a trim ring 30 for a foil of the type that is formed to have a substantially L-shaped cross section so as to extend along the inner wall of the foil rim 3. That is, as shown in FIG. 7, a metal strip material is formed to form a cylindrical body, and the abutting portions 22 at both ends are shaped as shown in FIGS. 3a and 3b.
As shown in the figure, a ring-shaped body is obtained by welding leaving both ends intact, and both edges 30h, 30h of this ring-shaped body including non-welded portions 30e, 30e are bent inward. As a result, the non-welded portions 30e, 30e are
It does not appear on the outside.

〔Effect of the invention〕

As explained above, according to the present invention, after welding leaving both ends of the abutting part, both edges including the non-welded parts at both ends are bent inward, so that the non-welded parts are not visible. The appearance can be improved.

[Brief explanation of drawings]

1 to 6 are process diagrams showing an embodiment of the method for manufacturing a foil trim ring according to the present invention,
7 and 8 are diagrams showing other embodiments of the present invention,
FIGS. 9 to 11 are diagrams showing an example of a conventional method for manufacturing a trim ring for foil. DESCRIPTION OF SYMBOLS 1... Trim ring for foil, 2... Foil cover, 3... Rim, 6... Bent piece, 7... Bent part, 22... Butt part, 22e... Non-welded part.

Claims (1)

[Scope of Claims] 1. A method for manufacturing a foil trim ring formed into an annular shape corresponding to a foil rim, comprising: butting both ends of an annularly formed metal plate;
A process of manufacturing an annular body by welding the abutted part, leaving both ends of the abutting part, and a process of bending both edges of the annular body inward, including the non-welded parts at both ends of the welded part of the annular body, to produce a non-welded part. A method for manufacturing a trim ring for foil, characterized by including a pressing process in which a welded part is not visible in appearance. 2. The method for manufacturing a foil trim ring according to claim 1, wherein the annular body is integrated with the outer periphery of the synthetic resin foil cover during the pressing step. 3. The method for manufacturing a trim ring for a foil according to claim 1, wherein the annular body is flat or cylindrical.