JPS59197317A - Method and device for bending sheet material - Google Patents

Abstract

PURPOSE:To obtain a valuable product without leaving straight parts at the side parts of a bent sheet materials by bending the material fed into a gap between opposing rolls as well as pressing the rolls against the side faces of the material. CONSTITUTION:A sheet material 13 is fed between an upper roll 14 and a lower roll 15 and a bending moment is given by pressing its both surfaces, then the material 13 is bent into a shape corresponding to a roll shape and, at the same time, the side face 16 of material 13 is pressed by forming a side-face pressing part 17 for pressing the side face 16. In this way, the material 13 is bent without leaving straight parts at its side parts, and is processed into a pipe without causing increased wall-thickness parts, and a valuable product is obtained. Further, rolls for pressing the side faces of material can be provided separately from upper and lower rolls.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for bending a plate material and a bending apparatus that prevents straight portions from remaining in 1% of the bent plate material.

When making metal pipes, a method is sometimes used that involves bending a plate and then welding the ends of the circularly bent plate to each other. In this case, the plate material is bent several times little by little.

BACKGROUND OF THE INVENTION Conventionally, when bending a plate, a device shown in FIG. 1 is used in the following manner. That is, a bending moment is applied to the plate material 3 by sandwiching the plate material 3 between an upper roll 1 having a circular arc with a smaller diameter closer to both ends and a lower roll 2 having a circular arc with a larger diameter closer to both ends. and bending the plate 3. The plate material 3 is bent into a circular shape by performing the bending process of the plate material 3 stepwise multiple times.

However, by simply adding a moment tube to the plate material, if the plate thickness is t, then 1-(1,0~1
．． 5) There is a drawback that a straight part with a length of t remains (see Fig. 2), and this straight part remains even when the pipe is formed. In order to prevent straight parts from remaining when the pipe is made, at the end of the bending process of the plate, the third
As shown in the figure, when a large pressure is applied from around the plate material 3 using the rolls 4 to 7 of the fin pass stand 8, the inner part of the plate material 3 is
A thickened portion 9 is formed in A11, resulting in a pipe with non-uniform wall thickness.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate such drawbacks and to provide a method and a bending device for bending a plate in which no straight portion remains on the plate when the plate is bent.

The structure of the method of bending the plate material to achieve this purpose is as follows:
In a method of bending a plate material, the plate material is fed between opposing rolls, and the rolls press both sides of the plate material to bend the plate material into a shape corresponding to the shape of the rolls. The structure of the plate bending device is characterized in that the plate bending device is equipped with rolls that press the plate from both sides of the plate to bend the plate into a predetermined shape, in which any of the rolls presses the plate. The present invention is characterized in that a side surface suppressing portion for pressing the side surface of the plate material is formed on the roll, or a side surface suppressing roll for pressing the side surface of the plate material is separately provided.

The present invention will be explained in detail below.

In the method of bending a plate according to the present invention, the plate is fed between opposing rolls, and the rolls are pressed against the sides of the plate during bending. As a result, the fourth
As shown in the figure, a pressing force is applied to the plate material 10 from both sides of the plate material 10 to generate a bending moment M, and a pressing force is also applied to the side surfaces 11 and 12.

Next, a plate bending apparatus for carrying out the bending method according to the present invention will be described with reference to examples.

Note that the sheet material bending device according to the present invention has an improved roll that comes into direct contact with the sheet material to be bent.
The explanation of other parts will be omitted and only the role will be explained.

FIG. 5 shows a side surface suppressing portion that presses the side surface 16 of the plate material 13 on the upper roll 14 in this embodiment, of the upper roll 14 and the lower roll 15 that press the plate material 13 from both sides of the plate material 13 and bend it into a predetermined shape. 17 is partially shown.

The side surface pressing portion 17 rotates together with the upper roll 14 and performs the same function as a separate roll rotating to press the side surface 16 of the plate material 13.

FIG. 6 shows upper rolls 20, 21.
, and a lower roll 22, the plate material bending device is separately provided with a side roll 25 for pressing the side surface 24 of the plate material 23 to be bent between the upper roll 20.21 and the lower roll 22. It is something that

The bending device shown in FIG. 7 is rotatably provided on a support frame 26 via a shaft 27, and includes upper rolls 28, 29, (-) and a lower roll 30, which are integrally formed. At the same time, (l!+1
It is composed of side rolls 34 for pressing the sides, and a lower roll part 33 which can be bent by sandwiching the vicinity of the part from both sides.

As mentioned above, when a plate is bent using the plate bending device shown in Figs. 5 to 7, not only is a bending moment applied to the plate, but also a pressing force is applied to the first surface of the plate, so that the bent plate can be bent. There are no straight parts left in the uniform part, so there is no thickened part in the finished pipe.

In addition, in FIG. 5, the side surface suppressing portion is formed on the upper roll, but it may be formed on the lower roll.

υAs described above in conjunction with the drawings, according to the present invention, not only a bending moment is applied to the plate material, but also a roll for suppressing the side surface is provided to press the side surface of the plate material, so that the bending of the bent plate material is It is possible to obtain a product with high commercial value without leaving any straight parts.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of a plate bending device to explain a conventional plate bending method, Figure 2 is a cross-sectional view of a plate bent using the conventional plate bending device, and Figure 3 is a fin pass stand. FIG. 4 is an explanatory diagram showing the method of bending a plate according to the present invention, and FIGS. 5, 6, and 7 are examples of the plate bending apparatus according to the present invention, respectively. FIG. In the drawing, 10.13, 23.31 are plates, 11.12, 16, 24, 32 are side surfaces, 14.20, 2
1, 28.29 is the upper roll, 15.22.30 is the lower roll, 17 is the side suppression part, and 25.34 is the side roll. Patent Applicant: Mitsubishi Heavy Industries, Ltd. Sub-Agent Patent Attorney: Shibu Mitsuishi (and 1 other person) 7- Figure 1♂ Figure 2-〇jo 105-

Claims (1)

[Scope of Claims] (1) A method of bending a plate material by feeding the plate material between opposing rolls, pressing both sides of the plate material with the rolls, and bending the plate material into a shape corresponding to the shape of the rolls. A method for bending a plate material, characterized in that the roll is pressed against a side surface of the plate material while the plate material is being bent by the roll. (2) In a plate bending device equipped with rolls that press a plate from both sides of the plate to bend it into a predetermined shape, one of the rolls is provided with a side pressing portion that presses the side surface of the plate. (3) In the plate bending device equipped with rolls that press the plate from both sides of the plate to bend it into a predetermined shape, the plate bending apparatus includes a roll for pressing the side surface of the plate. A plate bending device characterized in that it is separately provided.