JPS59159220A - Bending method of sheet metal or the like - Google Patents

Abstract

PURPOSE:To make an external appearance of a joined part smooth and to enhance an operability in welding by performing a bending by providing a notch having a shape of isosceles triangle, which is formed so that a perpendicular dropped from its vertex coincides with a bending line of one side and the adjoining bending lines intersect each other at the vertex, in manufacturing a box body. CONSTITUTION:In manufacturing a box body by bending a metallic plate at one stroke after providing notches to the plate; a notch 5 having an isoscels triangle shape, provided to the position where an intersection 6 of bending lines 2a, 2b is a vertex of the triangle and a perpendicular 7 dropped from the vertex coincides with the bending line 2b at one side, is cut out. Next, the plate is bent along the bending lines 2a, 2b, and a joining part is butt-welded. By this method, an external appearance of the joining part is made smooth, and an enclosing construction by welding is made practicable, and the safety of operation is improved. This method is also applicable to the manufacturing of box body by two times welding.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a manufacturing method for manufacturing a box or the like by bending a metal plate.

BACKGROUND ART Conventionally, when manufacturing a box or the like having three perpendicular planes by sheet metal bending, the process was carried out as follows.

Figures 1 and 2 show a conventional example of a corner part when a container-shaped box is created by one-time bending and pressurization. Figure 1 is a developed view of a metal plate, and Figure 2 is a folded FIG. 3 is a perspective view of a corner after processing. Also, 1 is a metal plate, 2a and 2b are bent parts, and 3 is
In the conventional technology constructed as described above, a notch is cut out in a rectangular shape with two sides of the bent portions 2a and 2b, and 4 is a joint portion after the notch is bent. After cutting the notch 3, bend it along the bent parts 2a and 2b,
The joint 4 was built up by welding. This means that
If an attempt is made to finish by bending only, the cut end of the cutout 3 will be exposed at the joint 4, which is not only unfavorable in terms of appearance but also poses a risk of injury to the human body, etc. To prevent this, Generally, the build-up was done by welding. However, even in this case, the joint 4 is only in line contact with one side of the end face of the metal plate 1 as shown in the figure, and it is corner welded, which is extremely difficult to weld. Unless the welding material is built up using an auxiliary welding agent such as a welding rod, welding defects are likely to occur and liquid leakage may occur. Furthermore, even when finishing by polishing or the like, it is difficult to do the work because it is a corner part, and considerable skill is required to finish it with a good appearance.

The present invention has been made in view of the above-mentioned drawbacks of the prior art, and is an isosceles triangle whose apex is the intersection of two bent portions and whose perpendicular line is on the same line as one of the bent portions. By making a notch in the shape and then performing the bending process, it is possible to fold sheet metal, etc., which looks good and does not injure the human body, and can be easily and reliably welded when building a sealed structure or increasing strength. A bending method is provided.

Hereinafter, the present invention will be explained in detail according to the embodiments shown in FIGS. 3 to 8.

Fig. 3 and Fig. 4 show an example in which a container-shaped box is created by one bending process, and Fig. 3 is a developed view;
FIG. 4 is a perspective view after the bending process. Further, 5 has the intersection 6 of the bending parts 2a and 2b as the apex, and the perpendicular line 7 is the bending part 2.
This is an isosceles triangular notch provided at the same position as b, and 8 is the joint after bending.

In the embodiment of the present invention as described above, first, the bending portion 2
a and 2b are determined, and a notch 5 is cut out with the intersection point 6 as the apex. Next, fold along the bending lines 2a and 2b.
.

According to the embodiment of the present invention manufactured as described above, the corner portion or the sheet metal is bent, and there is no sharp portion at the end of the cut surface, so the appearance is improved and the appearance is desirable. , it is also safe for the human body.

Furthermore, even when welding is used to create a sealed structure or to provide strength, the joints are welded by butt welding, which simplifies the welding work and eliminates welding defects, making it possible to perform reliable welding. This makes it possible to create a welded container that is easy to weld and does not leak when used as a container for liquid or the like.

Further, according to the manufacturing method of the present invention, since welding is performed on the flat surface, the container can be finished by polishing or the like, and the finished state is good and the appearance is good.

Next, a first embodiment in which a box forest is manufactured by folding twice will be described with reference to FIGS. 5 and 6.

FIG. 5 is a developed view, and FIG. 6 is a perspective view after the bending process. 9 shows the first bent part 2a and the second bent part 1.
The notch is provided at a position where the intersection point 13 of 0b is the apex and the perpendicular line 11 is on the same line as the first bent portion 2a. Also, when the metal plate processed as shown in Fig. 5 is bent, it becomes as shown in Fig. 6, where 8 is the joint part consisting of the notch 5,
Reference numeral 12 denotes a joint portion consisting of a notch.

As described above, the first embodiment in which a box or the like is manufactured by two folding processes has the same effect as the case in which a box or the like is manufactured by one bending process.

Furthermore, Fig. 7 and Fig. 8 show a second embodiment in which a box body etc. is manufactured by folding twice. FIG.

On the other hand, when bending a metal plate at right angles, cutouts 5 and 8
The goal can be achieved by making the apex angle of

As explained above, according to the method for manufacturing corners of a box according to the present invention, an isosceles triangular shape is formed at a position where the intersection of adjacent bent portions is the apex and the perpendicular line is on the same plane as one of the bent lines. Although it is a simple method of forming a notch and then performing a bending process, the joints are no longer at the corners, resulting in a better appearance, and the welding that was conventionally done to improve the appearance is no longer necessary. In addition, the welding work performed to improve the sealed structure or strength is butt welding, which improves workability and allows finishing work such as polishing to be performed easily.

Furthermore, since the corners are bent and the sharp edges of the metal plate are not exposed, it is safe for the human body of the worker.

[Brief explanation of drawings]

FIGS. 1 and 2 show examples of the prior art, with FIG. 1 being a developed view and FIG. 2 being a perspective view after bending. Figures 3 to 8 show embodiments of the present invention; Figure 3 is a developed view of a case in which a box is manufactured by one-time bending, Figure 4 is a perspective view of the same, and Figure 5 is a two-fold bending process. FIG. 6 is a perspective view of the first embodiment, FIG. 7 is a development view of the second embodiment, and FIG. 8 is a development view of the first embodiment when manufacturing a box by processing. It is a perspective view of the second embodiment. 1‥Metal plate, 2a, 2b‥First bent portion, 10a, 10
b. Second bending part,

Claims (1)

[Claims] 1. In a method of manufacturing a box by bending a metal plate after providing a notch, the intersection point of adjacent bent portions is the apex, and the electric wire is the same as one of the bent portions. - A method for bending sheet metal, etc., characterized in that the bending process is performed after providing an isosceles triangular notch on a line. 2. Place the isosceles triangular notch at a position where the apex is the intersection of the adjacent first bent portions and the perpendicular line is on the same line as one of the first bent portions, and the first bent portion and the first bent portion. Claims characterized in that the bending is performed in two stages after the bending is done in two places, with the intersection of the second bending part being the apex and the perpendicular line being on the same line as the first bending part. The method for bending sheet metal, etc., described in item 1. 3. The method for processing sheet metal, etc. according to claim 1 or 2, characterized in that the apex angle of the isosceles triangular notch is a right angle.