JP3488266B2 - Bending method of square edge of plate-shaped member - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous opening formed by bending a plate-shaped member at an edge portion of a rectangular opening at a required height to either side of a front surface or a back surface. The present invention relates to a method for bending a rectangular end edge of a plate-shaped member, which comprises forming the bent edge by press working.

[0002]

2. Description of the Related Art Conventionally, an edge of a rectangular opening formed in a required portion of a plate-like member such as a so-called color metal plate which is covered with a synthetic resin on the surface of an iron or aluminum plate and which cannot be welded. In order to form a continuous bent edge that is bent and projected at the required height on either side of the front and back sides, make a notch in each corner of the square edge, The horizontal straight parts were separately bent by pressing, or the square edge was pressed by a metal mold and bent.

[0003]

The method of forming a notch in each corner of the rectangular edge and bending it with a press is as follows.
Since the work method is easy and the processing cost is low, each corner of the bent edge is cut, so when using the plate-shaped member as a decorative plate, it is necessary to cover the cut portion with another suitable material. There is a drawback that the member must be attached to each corner.

Further, the method of bending the rectangular edge portion by a press using a mold is simple in the bending work itself, but has a drawback that it is difficult to manufacture the mold. In particular, when the rectangular edge has a short length and a small area, the mold and pressing machine used may be small, so this does not pose a problem, but the length of the opening is 1 m or more and the area is also small. In the case of a large size, the mold and pressing machine to be used also need a large size, and the equipment cost is high, so it is good for mass production, but the processing cost is high for small volume production. Often unprofitable.

[0005]

SUMMARY OF THE INVENTION The present invention has been made by paying attention to such conventional problems as described above. An object of the present invention is to solve the above-mentioned problems by forming connecting portions at both ends of the bent edge near the corners of the rectangular opening when forming the bent edge.

The present invention, on the edge of the rectangular opening that is formed in a plate-like member, at the required height to either side of the front and back side, continuous
Subsequently , when forming the bent edge part that is bent and projected by press working, the bent edge part is formed at the opposite long edge part, and the bent edge part is formed at both ends thereof. After forming connecting portions each formed of a curved surface in which the end portion and the end edge portion are connected, a bent edge portion is formed at each of the U-shaped end edge portions including the opposite end edge portion and the connecting portion. It is a method of bending a rectangular edge of a plate-shaped member, which is characterized by being shaped.

[0007]

[Function] Since the connecting portions formed by the curved surfaces in which the bent edge portion and the end edge portion are continuous are formed at both ends of the bent edge portion, the crack phenomenon which is likely to occur at the time of press working is formed at both ends of the bent edge portion. In addition to preventing the above, the crack phenomenon at the time of pressing the upper and lower U-shaped edge portions can be prevented, and the adjacent bent edge portions can be connected smoothly and beautifully.

[0008] By cutting and cutting the long end edges and the U-shaped end edges including the short end edges by pressing, it is possible to achieve the latter difficulty in downsizing of the die, resulting in a large size. You can avoid investment in molds and presses.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on an embodiment shown in FIGS. Perforated with a required area in the central portion of the plate-shaped member 1 (FIG. 1), which is a decorative plate made of a colored aluminum plate whose surface is covered with a synthetic resin and is stretched on both sides of the door frame of the metal entrance door. A bending method for forming a continuous bent edge 4 on the edge 3 of the formed rectangular opening 2 will be described.

First, after the lower die 5 is installed on the lower surface (the back surface of the plate-shaped member 1) of the edge portion 3 ₁ (right side in FIG. 2A) of one of the longer sides of the opening 2, and the upper die fixed press plate member 1 (not shown) and pressed to form a bent edge portion 4 ₁ was bent protruding on the back surface at the required height. Again forming the bent edge portions 4 _1, at both ends of the bent edge portion 4 ₁ at the corners 2 'vicinity of the opening 2 and a curved surface continuous and a bent edge portion 4 ₁ and the edge portion 3 ₁ The connecting portions 6 and 6'are simultaneously formed.

[0011] Next, the even edge 3 ₁ edge 3 ₂ opposing longer to, by pressing with the upper and lower mold in the same manner as in the edge portions 3 _1, folded The edge portion 4 ₂ and the connecting portions 6, 6 ′ which are curved surfaces in which the bent edge portion 4 ₂ and the end edge portion 3 ₂ are connected to each other are formed at both ends thereof.

Subsequently, the upper connecting portions 6 and 6, both end edge portions 3 ₁ and 3 ₂ connected to the connecting portions 6 and 6, both corner portions 2 ',
The U-shaped edge portion 7 composed of 2'and the shorter edge portion 3 ₃ is formed into a bent edge portion 4 ₃ by press working using the upper and lower molds which has been conventionally performed. To do.

Further, the lower connecting portions 6 ', 6', both end edge portions 3 ₁ , 3 ₂ connected to the both connecting portions 6 ', 6', both corner portions 2 ', 2', and the shorter end edge. the part 4 ₄ which shaped edge portion 7 of the co consisting ', by press working using upper and lower mold in the same manner as in the above, to form a folded edge 4 _4, a rectangular shape A bent edge 4 continuous with the edge 3 of the opening 2 is formed.

The plate-shaped member 1 having a bent edge 4 continuous with the edge 3 of the rectangular opening 2 is stretched over the door frame of a metal entrance door with the bent edge 4 inside. It is used, for example, to fit a packing to the bent edge portion 4 to hold a glass plate mounted inside the door frame.

In this case, the longer bent edges 4 ₁ , 4 ₂
Both ends of each two bent edge portions 4 _1, 4 ₂ and both end edge portions 3 _1,
Since the connecting portions 6 and 6'consisting of curved surfaces that are continuous with 3 ₂ are formed, the cracking phenomenon that is likely to occur at the time of press working at both ends of the bent edge portions 4 ₁ and 4 ₂ is prevented, and the upper and lower U-shapes are formed. To prevent the cracking phenomenon at the time of press working of the edge portions 7 and 7'of a circular shape, and to make the connection between the adjacent bent edge portions 4 ₁ , 4 ₂ and 4 ₃ , 4 ₄ beautifully without any trouble. You can

Further, the U-shaped end edges 7 including the longer end edges 3 ₁ , 3 ₂ and the shorter end edges 3 ₃ , 3 ₄ .
By separating from 7'and press-working, it is possible to reduce the size of the latter die which is difficult, and it is possible to avoid investment in a large die or press machine.

In the above embodiment, the plate-like member 1 which is a color aluminum plate obtained by coating an aluminum plate with a synthetic resin.
However, a colored iron plate obtained by coating an iron plate with a synthetic resin or the like may be used instead of the colored aluminum plate.
The synthetic metal plate not coated with a resin, for example, stainless steel plate even in the case of forming a continuous folded edges edge shape opening towards the large area, such as may be applied. In this case, the processing cost of the stainless plate can be reduced.

If an arcuate notch 8 (shown by the dotted line in FIG. 1A) is cut and formed in each corner 2'of the rectangular opening 2 of the plate-like member 1, the upper and lower corners will be cut. When the bent edges 4 ₃ and 4 ₄ are formed on the letter-shaped edge portions 7 and 7 ′ by pressing, it is possible to prevent the occurrence of cracks at the corner portions 2 ′ and bend them beautifully.

[0019]

According to the present invention, both ends of the bent edge of the edge are
By forming a connecting portion composed of a curved surface in which the bent edge portion and the end edge portion are continuous, the edge portion of the rectangular opening portion of the plate-shaped member is formed on the edge portion of the plate-like member in the same manner as conventional press working with a simple die. Since it is possible to form a continuous bent edge very easily, the processing cost can be reduced and the product price can be reduced.

According to the present invention, the latter, which is difficult to downsize, is cut by pressing the long end edges and the U-shaped end edges including the short end edges separately. It can be measured, avoiding investment in large molds and presses, and can be easily manufactured in small and medium enterprise factories.

[Brief description of drawings]

FIG. 1 is a plate-like member used in one embodiment of the present invention, in which (A)
Is a front view, (B) is a sectional view taken along line AA.

FIG. 2 is a partially cut plate member for explaining a bending method according to an embodiment of the present invention, in which (A) is a front view,
(B) is BB sectional drawing.

FIG. 3 is a partially cut plate member for explaining a bending method according to an embodiment of the present invention, in which (A) is a rear view,
(B) is CC sectional drawing.

FIG. 4 is a back view of a partially cut plate member for explaining a bending method according to an embodiment of the present invention.

[Explanation of symbols]

1 plate-like member 2 square-shaped opening 3, 3 ₁ , 3 ₂ , 3 ₃ , 3 _{4 end} edge part 4, 4 ₁ , 4 ₂ , 4 ₃ , 4 ₄ bent edge part 6, 6'connecting part 7, 7'U-shaped edge 8 Notch

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Claims (2)

(57) [Claims] Claims: 1. A fold formed by continuously bending and projecting an edge portion of a rectangular opening formed in a plate-like member at a required height toward either side of a front surface or a back surface. When the curved edge is formed by press working, the curved edge is formed at the opposite long edge of the curved edge, and the curved edge and the edge are connected to each other at both ends thereof. After forming the connecting portions each consisting of, in the U-shaped edge portion including the opposing short edge portion and the connecting portion,
A method for bending a rectangular edge of a plate-shaped member, characterized in that each bent edge is formed. 2. The plate-like member according to claim 1, wherein a plate-like member is used, in which arcuate notches are formed at the respective corners of the edge of the rectangular opening. Method of bending rectangular edge of member.