JP2013169549A - Bending device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bending device capable of suppressing fluctuation of a bending amount of a metal sheet.SOLUTION: A bending device 100 is provided with: a processing plinth which has a plurality of support parts 12 where a metal sheet extending in a horizontal direction is supported at least total three points from the below and has a concave face which is formed at a space inside these plurality of support parts 12, makes the support parts 12 connect with each other, and has a concave face having a concave shape downward; and a linear heating part 30 which is arranged above the processing plinth and applies linear heating processing to the metal sheet installed on an installation face 11.

Description

  The present invention relates to a bending apparatus for bending a metal plate three-dimensionally by subjecting the metal plate to linear heating.

For example, bending of a steel plate for shipbuilding at a shipyard or a metal plate used for an inner liner of a reactor containment vessel is performed by linear heating (see, for example, Patent Documents 1 and 2).
In this bending process by linear heating, the surface of a flat metal plate is linearly heated by a laser or the like from above, and the metal plate is contracted by the plastic strain generated thereby. Then, the metal plate is bent so as to be bent starting from the heating location, and the both side portions of the heating location are displaced so as to rise toward the surface side, that is, upward. Thus, in the bending process, an intended three-dimensional curved surface shape is created.

Japanese Patent Laid-Open No. 5-76947 JP 2009-12058 A

By the way, in the bending process by the said conventional linear heating, there existed a problem that dispersion | variation produced in the amount of bending processes by the influence of the weight of a metal plate.
That is, as shown in FIG. 7, when the both sides of the heating location are displaced so as to float upward, a bending moment due to their own weight acts on both sides of the heating location with the heating location as a fulcrum. The direction of this bending moment is opposite to the bending direction of the metal plate by linear heating, that is, downward. Therefore, when the displacement of both sides of the metal plate is canceled out by the bending moment, the amount of bending of the metal plate that is initially expected cannot be obtained, and the predicted shape and the actual shape of the metal plate are different. It becomes.

As a result, when a variation occurs in the amount of bending, a separate operation is required to match the final amount of bending, leading to an increase in cost due to an increase in the number of processing steps.
Further, the variation in the bending amount becomes more remarkable as the metal plate has a larger bending moment. On the other hand, in the case of bending by a skilled engineer, it is possible to suppress the variation in the bending amount depending on the skill level, but when the bending is automated, the variation in the bending amount Cannot be avoided.

  This invention is made | formed in view of the said subject, Comprising: It aims at providing the bending apparatus which can suppress the dispersion | variation in the bending amount of a metal plate.

In order to solve the above problems, the present invention provides the following means.
That is, the bending apparatus according to the present invention is formed in a plurality of support portions that support a metal plate extending in the horizontal direction from below at a total of three points, and a space inside the plurality of support portions. A processing base having an installation surface that forms a concave curved surface that is connected to each other and is recessed downward, and a linear heating process is performed on the metal plate that is provided above the processing base and that is installed on the installation surface. And a linear heating unit.

When bending a metal plate with this bending apparatus, first, the metal plate is supported at a total of at least three points by the support portion of the processing base. When linear heating processing is performed from above the metal plate in this state, the metal plate is dropped into the concave curved surfaces inside the plurality of support portions by bending both sides starting from the heating location. Finally, the metal plate has a three-dimensional curved surface shape corresponding to the shape of the concave curved surface.
In this way, by forming the three-dimensional curved surface while dropping the metal plate supported by the support portion into the concave curved surface, both side portions of the linear heating portion in the metal plate do not float upward from the processing base. Therefore, generation | occurrence | production of the bending moment by the dead weight of a metal plate can be suppressed.

In the bending apparatus according to the present invention, it is preferable that the concave curved surface has a spherical shape.
Thereby, the metal plate can be easily formed into a spherical three-dimensional curved surface shape.

Furthermore, in the bending apparatus according to the present invention, the concave curved surface may have a cylindrical surface shape.
Thus, the metal plate can be easily formed into a cylindrical three-dimensional curved surface shape.

In the bending apparatus according to the present invention, it is preferable that the radius of curvature of the concave curved surface is set smaller than the radius of curvature of the final processed shape of the metal plate.
Thereby, the metal plate before the final processed shape can be easily obtained, and a desired three-dimensional curved surface shape can be easily obtained by the subsequent final processing.

  According to the bending apparatus of the present invention, since it is possible to suppress the generation of a bending moment due to the weight of the metal plate, it is possible to suppress variations in the amount of bending due to the weight of the metal plate.

It is a perspective view of the bending apparatus which concerns on embodiment of this invention. It is a perspective view of the state which is giving the linear heating process to the metal plate in the bending apparatus which concerns on embodiment of this invention. (A) is a perspective view which shows the state which is performing the linear heating process with respect to a metal plate, (b) is a perspective view which shows the state of the metal plate after a linear heating process. It is a perspective view of the state after performing a linear heating process to the metal plate in the bending apparatus which concerns on embodiment of this invention. It is a perspective view of the bending apparatus which concerns on the 1st modification of this invention. It is a perspective view of the bending apparatus which concerns on the 2nd modification of this invention. It is a figure which shows the state which gave the linear heat processing to the metal plate conventionally, and was bent.

Hereinafter, a bending apparatus according to an embodiment of the present invention will be described in detail with reference to FIGS.
The bending apparatus 100 performs bending on a metal plate 200 by linear heating on a flat metal plate 200. As shown in FIG. 1, a processing base on which the metal plate 200 is installed. 10 and a linear heating unit 30 that performs linear heating processing on the metal plate 200 on the processing base 10.

As shown in FIG. 1, the processing base 10 has a substantially square shape in plan view, and is an installation surface 11 of the upper surface metal plate 200. .
The installation surface 11 of the processing base 10 has a concave curved surface shape that is concave downward, and in this embodiment, has a spherical shape. In addition, around the installation surface 11, a plurality of support portions 12 are formed so as to be continuous with the installation surface 11.

  The support portion 12 of the present embodiment is formed at each of a plurality of corner portions (four corner portions in the present embodiment) in plan view of the processing base 10, and upwards from the center of the installation surface 11 toward the corner portion. It is located at the outer peripheral end of the curved installation surface 11. The support portion 12 has a shape that is pointed upward, so that the metal plate 200 can be point-supported from below. Thus, in the present embodiment, the metal plate 200 can be supported from below by a total of four points by the four support portions 12. Note that the tip of the support portion 12, that is, the portion that supports the metal plate 200 is located on the same horizontal plane.

  As described above, the processing base 10 of the present embodiment is provided with the four support portions 12 that support the metal plate 200 extending in the horizontal direction, that is, the metal plate 200 arranged in parallel with the horizontal plane from below. An installation surface 11 having a concave curved surface shape that is concave downward is formed in a space inside the four support portions 12. Moreover, the part which supports the metal plate 200 in these support parts 12 and the installation surface 11 are smoothly connected to each other.

  Here, in this embodiment, the radius of curvature of the installation surface 11 having a concave curved surface shape is the same as the radius of curvature of the final shape of the metal plate 200 to be processed into a three-dimensional curved surface shape, or more than the radius of curvature of the final shape. It is set small.

  In the present embodiment, the linear heating unit 30 is configured to perform heating by irradiating the metal plate 200 with laser light H, and includes a laser head 3131, a moving mechanism 32 that drives the laser head 31, And a control device 33 that controls the moving mechanism 32.

  The laser head 3131 irradiates the metal plate 200 with the laser beam H for linear heating, and is installed so as to be able to irradiate the laser beam H downward above the processing base 10. When the metal plate 200 receives the energy of the laser beam H emitted from the laser head 31, only the irradiated portion of the laser beam H is locally heated.

  The moving mechanism 32 is configured to arbitrarily move the laser head 31 in the horizontal direction. For example, by combining a ball screw mechanism that linearly moves the laser head 31 in the horizontal direction, the moving head 32 moves the laser head 31 along the horizontal direction. It is configured to be movable in the direction and the Y direction. By driving the moving mechanism 32 as described above, the laser head 31 is moved in the horizontal direction while the metal plate 200 is irradiated with the laser beam H from above. As a result, a linear heating process can be performed on the metal plate 200. In addition, as long as the surface of the metal plate 200 can be heated locally, the structure heated with other than the laser beam H may be sufficient.

  The control device 33 controls the driving of the moving mechanism 32, and drives the moving mechanism 32 so as to draw a predetermined programmed locus, for example. The laser head 31 scans the metal plate 200 in accordance with the driving of the moving mechanism 32 like this, and performs a linear heating process on the metal plate 200.

Next, bending of the metal plate 200 by the bending apparatus 100 having the above configuration will be described.
First, as shown in FIG. 2, the metal plate 200 is installed on the four support portions 12 in the processing base 10. Thereby, the metal plate 200 is arrange | positioned so that it may extend in parallel with respect to a horizontal surface. At this time, the metal plate 200 may be installed on three of the four support portions 12 without arranging the metal plate 200 on all of the four support portions 12.

  Subsequently, as shown in FIG. 2, the surface of the metal plate 200 is linearly heated by the linear heating unit 30. That is, in a state where the laser beam H is irradiated from the laser head 31 of the linear heating unit 30 onto the surface of the metal plate 200, the driving unit is driven by the control device 33 to scan the laser head 31 in the horizontal direction. At this time, the laser head 31 scans the metal plate 200 so as to draw a locus programmed in advance by the control device 33, and the surface of the metal plate 200 is linearly heated by the laser light H along the scanning path. .

  When the metal plate 200 is heated from the surface in this way, as shown in FIG. 3A, the heated portion A of the metal plate 200 tends to locally expand. At this time, since the proof strength of the heated portion A that is softer than the surrounding is small by being heated, the compression yielding occurs due to the action of the compressive force from the periphery of the heated portion A as shown in FIG. Thereby, when the heating location A returns to the original temperature, the volume is reduced by the amount of compression yield. Thus, when the heating location A shrinks from the beginning, the surface side of the metal plate 200 is pulled toward the heating location A, and as a result, both sides of the heating location A as the metal plate 200 as a whole start from the heating location A. It will be in the state bent toward the surface side, ie, upward.

  Here, when such linear heating is applied to the metal plate 200, the metal plate 200 is bent starting from the linear heating location, so that the metal plate 200 is a concave curved surface inside the four support portions 12. It is gradually dropped into the installation surface 11 having a shape. That is, as the metal plate 200 is supported by the support portion 12 as the linear heating progresses, the bent portion gradually displaces toward the bottom of the concave curved surface, as shown in FIG. The metal plate 200 has a concave curved surface shape corresponding to the shape of the installation surface 11, that is, a spherical surface shape.

  Thus, since the metal plate 200 is bent in a state in which the periphery is supported by the plurality of support portions 12, only both sides of the heating portion of the metal plate 200 do not float from the installation surface 11. Further, in the process in which the metal plate 200 is bent and dropped onto the installation surface 11, the metal plate 200 is displaced while being in partial contact with the installation surface 11 having a concave curved surface shape. There is no big uplift. That is, by forming the three-dimensional curved surface while dropping the metal plate 200 supported by the support portion 12 into the concave curved surface, it is possible to avoid the end portion of the metal plate 200 from floating upward from the processing base 10.

  Here, when only the end of the metal plate 200 is lifted from the installation surface 11, a downward bending moment due to the weight of the metal plate 200 acts on the lifted portion, so that the initially predicted shape is obtained. And the bending shape of the metal plate 200 varies.

On the other hand, in this embodiment, since only the edge part of the metal plate 200 does not lift from the installation surface 11 as described above, it is possible to reliably suppress the bending moment from acting on the metal plate 200. it can.
Therefore, since it is possible to obtain the bending amount of the metal plate 200 as much as initially estimated, it is possible to avoid the predicted shape of the metal plate 200 from being greatly different from the actual shape, and variation in the bending amount. Can be suppressed.

  Moreover, in this embodiment, when the curvature radius of the concave curved surface which makes | forms spherical shape is set smaller than the curvature radius of the final process shape of the metal plate 200, the shape before a final process shape is easily obtained by bending. The desired three-dimensional curved surface shape can be easily obtained by subsequent final processing.

The embodiment of the present invention has been described above, but the present invention is not limited to this, and can be appropriately changed without departing from the technical idea of the present invention.
For example, as shown in FIG. 5, the bending apparatus 101 according to the first modification has a configuration in which the shape of the processing base 10 in a plan view is triangular, and support portions 12 are provided at the corners of the triangle. May be. That is, this bending apparatus has a configuration in which three support portions 12 are provided, and an installation surface 11 having a concave curved surface shape is formed inside the support portions 12.

  Even in this case, as in the embodiment, the metal plate 200 initially supported only by the support portion 12 is deformed so as to be dropped onto the concave curved surface along with the linear heating process. It is possible to suppress the bending moment from acting on.

  In addition to the first modified example, the number of the support portions 12 may be any number, and if the metal plate 200 can be supported by at least three points, the configuration in which five or more support portions 12 are provided. May be.

  Further, for example, as shown in FIG. 6, as the bending apparatus 102 of the second modification, the concave curved surface shape of the installation surface 11 may be a cylindrical shape. In this case, similarly to the embodiment, when the metal plate 200 falls on the installation surface 11 having a cylindrical surface shape, the metal plate 200 having a cylindrical surface shape as a three-dimensional curved surface shape can be easily obtained.

DESCRIPTION OF SYMBOLS 10 Processing base 11 Installation surface 12 Support part 30 Linear heating part 31 Laser head 31
32 Moving mechanism 33 Control device 100 Bending device 101 Bending device 102 Bending device 200 Metal plate H Laser light

Claims (4)

A plurality of support portions that support at least three points in total from below the metal plate extending in the horizontal direction, and a concave curved surface that is formed in a space inside the plurality of support portions and connects the support portions to each other and is recessed downward A processing pedestal having an installation surface having a shape;
A linear heating unit that is provided above the processing base and performs linear heating processing on the metal plate installed on the installation surface;
A bending apparatus comprising:   The bending apparatus according to claim 1, wherein the concave curved surface has a spherical shape.   The bending apparatus according to claim 1, wherein the concave curved surface has a cylindrical surface shape.   The bending apparatus according to any one of claims 1 to 3, wherein a radius of curvature of the concave curved surface is set to be smaller than a radius of curvature of a final processed shape of the metal plate.

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