JPH02165817A - Metallic plate and bending method therefor - Google Patents

Abstract

PURPOSE:To prevent a hole diameter from deforming even when a metallic plate is bent at a specified place by making a hole at a place a prescribed distance far from the assumed outside face of the bending part and providing a notch within a prescribed distance from the outside. CONSTITUTION:After the metallic plate performs a prescribed working, it is bent at a part of the bending plate 1b. A hole 1a is formed at a place a prescribed distance P far from the outside 1c of the bent part after bending is performed, which is assumed from the bending place 1b. A notch 2 is provided within a prescribed distance from the outside 1c. Thereafter, the metallic plate 1 is bent at the bending place 1b. By this method, a metallic plate excellent in finish appearance can be obtained.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a metal plate to be bent, a method for bending a flat metal plate, and a method for bending a metal plate in which a hole is formed in the vicinity of the bent portion. It is something.

[Prior Art] A flat metal plate is subjected to bending, cutting of holes, etc., and punching.

When holes are formed in the vicinity of these bending points, the bending and hole formation are performed in an order as required.

[Problems to be Solved by the Invention] In other words, this order is selected depending on each situation described below.

■) When bending after forming a hole.

Normally, when the thickness of the metal plate 1 is t, the distance P between the assumed outer surface 1c after bending and the end 1aa of the hole 1a closest to this outer surface 1c is set as P=2 t+2 (mm). .

Here, the second term in the above equation is a constant value based on experience.

As shown in the plan view of FIG. 7, when the flat metal plate lO is set to have a distance P + < P between the end 1aa of the hole 1a, after the hole is formed by punching, the shape shown in FIG. 8(a) , (b
), the vicinity of the hole 10a is bent, but the end 1 of the hole 10a near the bending point tab
0aa was pulled in the bending direction, resulting in a poor appearance and a defect in the diameter of the hole 10a. Further, since a portion of the hole 10a was bent, the bending dimension Ll could not be accurately obtained, resulting in a defect.

Therefore, when bending after forming a hole, the hole could not be formed near the bending point (within a predetermined pressure!tP from the bending point).

2) When forming a hole after bending.

In order to solve the above-mentioned problem, the hole 10a may be formed after bending the metal plate IO.

However, in order to form the hole 10a in the vicinity of the bending point tab, the metal plate 10 must be fixed, but there is a problem that it cannot be easily fixed because a predetermined bend has already been formed.

Further, when using a die such as a punch press machine that automatically forms the hole 10a, it cannot be used because there are models that punch out only a flat metal plate. Therefore, the holes are usually drilled manually. In this case, in order to make the hole 10a at an accurate location, punch the hole 10a in advance for positioning at the location where the hole is to be made before bending the metal plate 10, and then use a drill etc. to form the hole 10a after bending the metal plate 10. must be done.

In this case, the number of work steps was increased and the holes had to be deburred. Furthermore, since the hole 10a is formed near the bent portion, it may not be possible to remove the hole.

The present invention has been made in view of the above-mentioned problems, and aims to provide a metal plate that can obtain accurate bending accuracy and accurate hole diameter, and thereby has a good finished appearance. Furthermore, it is an object of the present invention to provide a method for bending a metal plate, which has the above-mentioned effects and can be easily formed with a minimum number of steps before bending the metal plate.

[Means for Solving the Problems] In order to achieve the above object, the metal plate of the present invention is a flat metal plate l that can be bent at a bending point ib after a predetermined processing.
A hole 1a formed at a predetermined distance P from the bent portion outer surface 1c after bending assumed by the bent portion, and a notch 2 provided within the predetermined distance from the outer surface. It is characterized by having the following.

Further, in the metal plate bending method, a metal plate bending method is performed when forming a bending point 1b in a metal plate l and a hole 1a at a position near the bending point, the metal plate being bent into a flat metal plate. After setting the location, positioning and forming the hole at a location a predetermined distance away from the bent portion outer surface 1c after bending assumed by the bending location,
Further, after forming the notch 2 within the predetermined distance from the outer surface, the metal plate is bent at a bending point ib.

[Function] According to the above metal plate, the notch 2 is provided in the bent portion 1b of the metal plate 1, and the hole 1a is provided at a predetermined distance P from the bent portion 1b via the notch 2. It will be done.

As a result, the metal plate l by the above-mentioned metal plate bending method is
The tensile force at the bending point ib that acts when bending is
The cutout 2 does not absorb and deform the predetermined diameter of the shadow formation of the hole 1a.

EXAMPLES] FIG. 1 is a plan view showing a metal plate 1 according to the present invention and a metal plate l to which a metal plate bending method is applied, and FIG. 2 is a flowchart showing the steps of the above method.

To explain the process in order, the hole part 1 in the metal plate l is
Set a and bending point 1b under the following conditions (SPI)
.

Assuming that the thickness of the metal plate 1 is t, the outer surface 1 after the assumed bending
c, and the end 1aa of the hole 1a closest to this outer surface 1c.
The distance P1 is set as P+ <P=2 t+2 (mm). Here, the second term is a constant value based on experience.

Next, 4 at a location within the above distance P and at the end 1a of the hole 1a.
A rectangular notch 2 having a central portion 2a and having a predetermined length is formed in a direction perpendicular to the outer surface 1c from a (SF
2). The length Kl may be set to be longer than the seed of the hole 1a, but it is sufficient that it is equal to the length of the chord where the hole 1a intersects with the outer surface 1c at a distance P, as shown in FIG.

As will be described later, the length 1 differs depending on the shape of the hole 1a adjacent to the bent portion 1b.

At this stage, the hole 1a and notch 2 have been formed in the metal plate 1, and the bending point 1b has been determined, so a flat metal plate 1 with holes processed before the bending stage is manufactured. become.

Next, by bending the metal plate 1 around the bending point 1b (SF3), the tensile force generated at the bending point 1b is shown in the front view and side sectional view of FIGS. 3(a) and (b). In this way, the diameter of the shadow formation of the hole 1a is not deformed by being absorbed by the notch 2 portion, and the bending dimension L2 can be accurately obtained.

Further, when forming a square hole 3a as shown in FIG. 4(a) instead of the hole 1a, the side portion 3aa becomes the end portion. At this time, the entire surface of the side portion 3aa is provided parallel to the bent portion 1b, and the entire side portion 3aa is similarly subjected to the bending action, so the notch 2 needs to have the same length Kl as the side portion 3aa. .

In addition, in the case of the diamond-shaped hole 4a shown in FIG. 4(b), the corner 4a
a becomes the above-mentioned end. If the length Kl of the notched hole 2 is set to the length of two points where the diamond-shaped hole 4a intersects at a distance of P from the outer surface 1c, the diameter of the hole can be similarly bent without deforming.

Although the notch 2 is formed in a rectangular shape, it may be in a circular shape as shown in FIG. ) may be a slit continuously formed on the outer surface 1c as shown in the side sectional view after bending, and in this case also the same effect as described above can be obtained.

If the width of the notch 2 is 0.5 mm or more, the metal plate 1 can be bent without deforming the hole 1a.

[Effects of the Invention] According to the metal R@ according to the present invention, a hole can be formed in the vicinity of a bending point, and the hole diameter can be prevented from deforming even if the metal plate is bent at the bending point.

Further, according to the above method for bending a metal plate, it is possible to obtain a metal plate with accurate bending accuracy and accurate hole diameter, thereby making it possible to obtain a metal plate with a good finished appearance. It has the advantage of being easy to form with minimal steps.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a metal plate and a metal plate before bending to which the metal plate bending method of the present invention is applied, and FIG. 2 is a flowchart 1-1 showing the steps of the above method. Figure 3 (
a) and (b) are a plan view and a side sectional view showing the state after bending the metal plate, and FIGS. 4(a) and (b) are plan views showing punching formation positions of holes of other shapes, Figures 5 and 6 (a
)teeth. FIG. 6(b) is a plan view showing a notch in another example; FIG. 6(b) is a side sectional view after the bending process of FIG. 6(a); FIG. 7 is a plan view showing a metal plate processed by conventional sheet metal processing. Figure 8(a),(b)
7 is a plan view and a side sectional view after bending the portion shown in FIG. 7. FIG. 1...Metal plate, l a = hole, 1aa-end of hole,
ib--bending point, 1c--outer surface, 2--notch, 2a--center, P--set distance, K1--
...(notch) length.

Claims (1)

[Claims] 1. A flat metal plate (1) that is bent at a bending point (1b) after a predetermined processing, the outer surface of the bent portion (1c) after bending assumed by the bending point.
) is formed at a predetermined distance (P) from the hole (1a
); and a notch (2) provided within the predetermined distance from the outer surface. 2. A sheet metal bending method for forming a bending point (1b) in a metal plate (1) and a hole (1a) in the vicinity of the bending point, the bending point being set in the flat metal plate. After that, the outer surface of the bent part after bending (1c
) After positioning and forming the hole at a location a predetermined distance (P) away from the outer surface and forming a notch (2) within the predetermined distance from the outer surface, bend the metal plate at a location (1b).
A metal plate bending method characterized by bending a metal plate.