JPS58224022A - Bending method of plate material - Google Patents

Abstract

PURPOSE:To simplify bending work and bend a plate efficiently by forming a drawn part in a body that narros a space formed by the first bending work before the second bending work of a plate. CONSTITUTION:A notch 24 is provided at the center of an end of an iron plate 21 having a plated layer and a coating film layer on the plated layer, and a pair of grooves 26 are provided along the edge of the plate on both sides of the notch. A nearly U-shaped part 27 is formed by the first bending process that bends the plated layer and coating film layer to outside. A convex part having nearly semi-circular sectional form is protruded as a drawn part by monoblock forming process to narrow the space 30 in the U-shaped part 27 near the first bending part 29. Then, a nearly L-shaped part 32 is formed by the second bending process bringing the edge part 25 inside. Thus, an overlapped part of the second bending part 34 of the L-shaped part and above-mentioned first bending part 29 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention includes a first bending step of folding and bending a plate material, and a second bending step of forming a second bending portion across the first bending portion. The present invention relates to a method for bending a plate material.

In this type of steel plate, the second bending process may cause cracks in the plate material at or near the area where the first bend and the second bend overlap, or in the case of a pre-coated steel plate that has been plated or coated in advance. Various measures have been taken to prevent damage to coatings such as plating or paint films.

1 and 2 are perspective views showing a conventional bending method. In FIG. 9, 1 is a plate material made of iron or the like having a plating layer 2 and a coating layer 3 on its surface; One end of the plate, 5 is a notch in the center, 6 is a pair of concave grooves provided along the edge of the plate on both sides of the notch, and T is a substantially U-shape bent by the first bending process. , 9 is the first bent part of this U-shaped part, 10 is a spacer made of iron or the like inserted into the space 11 inside the U-shaped part 1, and 12 in FIG. 14 is the second bent portion of this L-shaped portion, and 15 is the first bent portion 9 and the second bent portion 14.
This is the overlapped part with

According to the above configuration, by additionally mounting the spacer 10 in the space 11 formed by the first bending process, the second bending process 13 can be performed as if bending a plate material having a thickness t. As a result, the plate material 1 is bent at the overlapped portion 15 and its vicinity, the bending curvature is uneven, the surface is wavy, or the plated layer 2 or coating on the surface is damaged. Excellent bending can be performed without cracking the layer 3.

However, in this method, an extra and different process, such as manual work, of inserting and mounting the spacer 10 is required in the middle of the bending process, which is generally performed by press forming, and the entire process cannot be completed as a series of operations. There wasn't. Furthermore, the spacer 41 and the spacer 10 did not play any role in the final product, and from this point of view they were useless members. In addition, in some cases, the position of the spacer 10 may be shifted and the spacer 10 may not fulfill its role.

This invention has been made in view of the above-mentioned drawbacks, and at least before the second bending process, the plate material is provided with a wrinkled part that narrows the space formed by the first bending process. The present invention provides a method for bending a plate material, which includes a step of integrally forming a second bent portion in the vicinity of the bent portion.

An embodiment of the present invention will be described below with reference to FIGS. 3 to 5.

FIG. 5 is a diagram showing the completion of the first stage bending process.

FIG. 4 is an end view taken along line IV-IV in FIG. 3, and in FIG. A pair of concave grooves provided along the edge of the plate on both sides of the notch 25 and 26 at one end of the plate along the edge of the plate, 2
7 is a substantially U-shaped part bent by the first bending part processing step in which the plated layer 22 and coating layer 23 sides are bent outward; 29 is the first bent part of this U-shaped part; 30 is a U
The space 31° inside the letter-shaped portion 21 is a convex portion having a substantially semicircular cross section as a wrinkled portion that is protruded in the integral molding process so as to narrow the area near the first bent portion 29. In this embodiment, the opposing plates are provided with a slight gap between them.

FIG. 5 is a diagram showing the completion of the second stage bending process. In the figure, 32 is an abbreviated-shaped part formed by the second bending process in which the end 25 is bent inside, and 34 is this abbreviated part. The second bent part of the L-shaped part, 35 is the first bent part 2
9 and the second bent portion 34.

According to the above configuration, the convex portion 31 corresponding to the spacer 10
．． It is sufficient to form the groove simultaneously with the concave groove 26, then perform the first bending process, and then perform the second bending process. According to this method, not only the effort of inserting the spacer 10 can be saved, but also the processing cost and material cost of the spacer 10 itself can be saved, resulting in a significant cost reduction.

Furthermore, since there is no complicated insertion work, these bending processes can be performed in a series of automated processes, making it an extremely efficient bending method. In addition, when the bending curvature in the second bending process is small or when the bending angle is large, two or more protrusions 31 may be provided substantially parallel to each other, and the cross-sectional shape of the protrusions 31 may be changed to the opposing plate material. It is also possible to provide parallel flat portions. Further, it goes without saying that if the convex portion 31 is located close to the first bent portion 29, the effect of preventing damage to the plate material is great.

FIG. 6 shows another embodiment, which is different from the above embodiment.
This is an example in which the bending step 41 is performed so that the convex portion 42 is on the outside, and the same effect can be obtained even in such a case.

As explained above, according to the present invention, at least before the second bending process, the first bending part is formed on the plate material so as to narrow the space formed by the first bending part process.
By providing a step of integrally molding the second bent portion near the bent portion, the nine bending steps can be simplified.

This makes it possible to realize an efficient method for bending plate materials.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the state in which the conventional first bending part processing step has been completed, FIG. 2 is a perspective view showing the state in which the second bending step has been completed, and FIG. A perspective view showing a state in which the first bent portion processing step of a plate material according to an embodiment has been completed, FIG. 4 is an end view cut along the line tV-M in FIG. 3, and FIG. FIG. 6 is a perspective view showing another embodiment of the present invention. In the figure, 21 is a plate material, 27 is a substantially U-shaped part, 29 is a first bent part, 30 is a space, 31 is a convex part as a seam part, and 34 is a second bent part. Agent Shin Kuzuno - (1 other person)

Claims (1)

[Claims] +11 The first part surrounding the space formed by folding back the plate material
and a second bending step of forming a second bending portion that intersects with the first bending portion, wherein the plate material is at least before the second bending step. A method for bending a plate material, comprising the step of integrally molding a constriction portion that narrows the space in the second bent portion in the vicinity of the first bent portion. (2) A method for bending a plate material according to claim 1, characterized in that the convex portion is a groove-shaped constriction portion.