JP2001030013A - Slitted bending die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent damage by abutting in forming a rectangular flange next orthogonally crossed with the rectangular flange in the case that the rectangular flange which is previously bent is present at the time of bending a box by forming plural slits in edge parts for pressure-welding a sheet-shaped work of a bending die for bending by ironing a box-shaped product or the like. SOLUTION: The plural slits (relieves) 9 are cut in prescribed positions in a longitudinal direction in tip parts for pressing the work of a lower die 5. Each cut position in the longitudinal direction is decided by dimensions of a long side and short side of the prescribed box-shaped product. When an angle for correcting a spring back is (90+α) deg. at the time of secondary bending of a flange, the width by which thickness of the pressure welding part at the tip of the lower die 5 is abutted on the edges on the side of the flange parts 1 by the primary bending is relieved, that is, when the thickness of the work W is expressed by (t), it is defined as the dimension of about 3t. The number of slits 9 may be provided by the number compatible to the prescribed plural box-shaped products on the same lower die 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bending die having a slit, and more particularly, to a bending die having a slit having a function of preventing damage due to mutual contact of work pieces in a panel bender or the like.

[0002]

2. Description of the Related Art FIG. 3 shows a so-called "iron bending" of a sheet-like work in a conventional panel bender or the like.
Of the mold arrangement on the operating arm 4 is shown. 5 is a downward bending die for forward bending, and 6 is an upward bending die for reverse bending.
Each of these bending dies 5, 6 is usually formed in one piece.

Hereinafter, a case of forward bending using the downward bending mold 5 will be described.

FIG. 4 shows an example of a cross-sectional view of a main part of the processed part. W is a sheet-shaped sheet metal work to be processed into a box-shaped product, and is fixed in a pressing and holding state by an upper / lower presser die (top die) 7 and a receiving fitting (bottom die 8). The lower bending die 5 is configured such that the operating arm 4 is operated in the direction of the arrow, so that the projecting portion of the work W from the holding portion is bent by 90 ° as one flange portion.

FIG. 5 shows a processing order of each flange in a normal box bending process. In the case of this type of box bending, in order to eliminate the need to change the length of the top die 7 in the middle, usually, as shown in FIG. Make a bend. FIG. 6 shows the first short side 1
Shows the state in which the process moves to the second long side 2 after bending.

Generally, when each of these flange portions is bent at 90 ° by a bending mold 5, a work material W is required.
In consideration of the "spring back" phenomenon, the bending operation angle of the lower mold 5 needs to press the edge of the lower mold 5 by 90 ° + α ° as shown by the dotted line in FIG. There is.

[0008] For this reason, as shown in FIG. 8, an example of a box-bending product is shown in FIG.
In order to perform bending at an angle of + α °, an enlarged view of each corner angle portion A is shown in FIG. There is a problem in that the portion abuts and damages (deforms) 3.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and as described above, for example, when there is a right-angled flange that has already been bent during box bending, the next time It is an object of the present invention to provide a bending die having a slit so as not to cause contact damage as in the related art when forming a right-angled flange at right angles to the above.

[0009]

Therefore, in the present invention, an object of the present invention is to achieve the above object by providing a bending die having a slit as described below.

In a panel bender, when performing a second bending process on the work pressing edge of the bending dies 5, 6 for performing ironing bending for a box-shaped product of a sheet-like work,
A slit-forming bending die, characterized in that a plurality of slits are omitted to avoid abutting of a side bent vertically in a side of a flange in a first bending process.

[0011]

With the above-described bending die according to the present invention, for example, after forming a first pair of flanges at the time of box bending of a sheet-like work, at the time of forming a second pair of flanges perpendicular to these, the bending die is formed. Therefore, there is no fear of damaging the side ends of the first pair of flanges.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
An embodiment will be described in detail with reference to the drawings.

[0013]

FIG. 1 is a perspective view showing an external appearance of an embodiment of a lower bending die 11 for a front bending as a lower bending die for a panel bending according to the present invention, and FIG. Example of work processing layout plan (However, excluding presser die (top die) 7)
Are respectively shown.

(Construction) As shown in FIG. 1, a predetermined position in the longitudinal direction of the work pressing tip of the lower mold 5 of the embodiment of the present invention is
A plurality of slits (escapes) 9 are omitted.

The positions of the cutouts in the longitudinal direction are determined by the long side dimension and the short side dimension of a predetermined box-shaped product.
As shown in FIG. 8, at the 90 ° + α ° angle for springback correction at the time of the second flange bending, the press-contact portion at the front end of the bending process 5 is attached to the edge on the flange portion 1 side by the first bending process. When the width at which the contact portion escapes, that is, the thickness of the work material W is t, the dimension is about 3 t,
The number of these slits 9 can be provided in the same lower mold 5 in such a number as to be compatible with a predetermined plurality of box-shaped products.

(Other Embodiments) In the above embodiment, the lower bending die 5 for forward bending shown in FIG. 3 has been described. Even if a plurality of slits 9 are provided, the same effect can be obtained at the time of reverse bending.

[0017]

As described above, according to the present invention,
For example, when forming a first flange pair at the time of box bending of a sheet-like work, and at the time of forming a second pair of flanges perpendicular to the first pair of flanges, a bending die may be used to damage the side end portions of the first pair of flanges. There is no possibility of giving.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a lower mold of an embodiment.

FIG. 2 is an example of a plan view of a work processing arrangement using a mold.

FIG. 3 is an example of a side view of a mold operating arm.

FIG. 4 is an illustration of ironing bending

Fig. 5 Example of box bending process

FIG. 6 is an example of box bending secondary processing

Fig. 7 Springback phenomenon

FIG. 8 is an example of a conventional box bent product, (a) is an enlarged view of a portion A.

[Explanation of symbols]

 1 Short side of primary bending (flange) 2 Long side of secondary bending (flange) 3 Damaged contact 4 Working arm 5 Lower (bending) mold (for forward bending) 6 Upper (bending) mold ( 7) Pressing die (top die) 8 Receiving die (bottom die) 9 Slit (runaway) W Work

Claims (1)

[Claims] In a panel bender, when performing a second bending process on the edge portion for press-contacting the work of the bending dies 5, 6 for performing ironing bending for a box-shaped product of a sheet-like work, A slit-forming bending die, characterized in that a plurality of slits are omitted to avoid abutting of a side bent vertically in a side of a flange in a first bending process.