JP2972004B2 - Automatic creation of development drawings for bending - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for automatically preparing a developed view for bending, in which dimensions of each portion of the developed view required for bending are accurately set based on a finished dimension.

[0002]

2. Description of the Related Art Generally, when a product is obtained by bending, a developed view is required. On the other hand, with the automation of processing, attempts have been made to automatically create this type of developed view by CAD. For example, JP-A-63-130220
Been the invention described in JP-to form a box-like product, as in FIG. 12, the size of the cross-sectional shape and each part of the outline of the vertical and horizontal directions of the sheet metal _{H 1 ~H 3, W 1 ~W} 3
By inputting the material and thickness of the sheet metal as necessary, the development view D is automatically adjusted to the dimension corrected for the sheet thickness of the sheet metal and the elongation of the bent portion as shown in FIG. Is to be created. Regarding the overlap at the butting portion, a desired shape is selected from a plurality of types of butting patterns registered in advance, and the cutout shape of the corner portion is determined according to the shape of the butting portion. .

[0003]

However, in the above-described conventional configuration, the dimensions and bending shape of each part are input only in the vertical and horizontal directions of the sheet metal. Therefore, only a development view of a box-shaped product formed in a rectangular parallelepiped shape can be obtained. There is a problem that it cannot be formed. That is, as shown in FIG. 14A, a development view D for a product whose bottom is not square or rectangular.
Further, there is a problem that the conventional method cannot cope with a product P which is not box-shaped as shown in FIG.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to provide a method for automatically creating a developed view for bending, which can easily create a developed view even for a product other than a rectangular parallelepiped. It is assumed that.

[0005]

According to the present invention, in order to achieve the above-mentioned object, a process of drawing a shape of a main surface of a product to a reference shape with a certain scale relative to a finished size, and a bending process are performed. Drawing the bent shape, which is the cross-sectional shape of the portion to be cut, at a fixed scale with respect to the finished dimension for each side of the reference shape, inputting the material and thickness of the sheet metal to be bent, and corresponding to the bent shape. Connecting a bent piece to each side of the reference shape to create a first development view;
A process of creating a developed view and a second developed view in which the first developed view is modified so that no overlapping portion is formed between the bent pieces after bending, and elongation of the bent portion based on the material and thickness of the sheet metal. The process of determining the amount and the second based on the determined amount of elongation
And correcting the dimensions given to the developed view to obtain the intended developed view.

[0006]

According to the above construction, the drawing is performed with the shape of the main surface of the product as the reference shape, and the cross-sectional shape of the portion to be bent is drawn as the bending shape. By combining the above, a development view of the product can be obtained. That is, it is possible to easily create a development view for products of various shapes only by drawing the reference shape and the bent shape. The method further includes a step of correcting the first development view so that the bending pieces do not overlap with each other based on the first development view in a state where the bent pieces corresponding to the bent shape are connected to each side of the reference shape. Therefore, it is possible to create a development view only by a simple operation of drawing a reference shape and a bent shape. Furthermore, the amount of elongation of the bent portion is determined by the material and thickness of the sheet metal, and the dimension given by drawing the base shape and the bent shape based on the finished dimensions is corrected by the amount of elongation. By drawing, the dimensions of each part in consideration of the amount of elongation are automatically determined, and the optimal dimensions are set to obtain a product having the desired dimensions.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, description will be made mainly on the assumption of bending a fixed product such as a building exterior wall panel. The apparatus used in the present invention is, as shown in FIG. 2, an input means 1 having a keyboard and a pointing device.
And a first developed view creating means 2 for creating a first developed view by combining the reference shape and the bent shape created by the input means 1, and correcting the first developed view so that no overlapping portion is formed in the bent piece. A second developed view creating means 3 for creating the second developed view, a dimension calculating means 4 for obtaining dimensions of each part of the second developed view based on an input from the input means 1, and a developed view as a calculation result is output Output means 5 such as a display device, a printer, and a magnetic storage means. The first development view creation means 2, the second development view creation means 3, and the dimension calculation means 4
It is constituted by a computer device.

The procedure for creating a development view in the present invention is as shown in FIG. First, a reference shape, which is a shape of a main surface (generally, a bottom surface) of a product, is drawn with a scale of a certain scale with respect to a finish size (step S1). That is, drawing is performed using a pointing device or the like so that a desired reference shape is displayed on the screen of the display device. Next, as shown in FIG. 3, a bent shape Y as a cross-sectional shape of a portion where each side of the reference shape X is subjected to the bending process is drawn on a scale of a fixed scale with respect to the finished size (step S).
2). Here, it is assumed that when the bending shape Y is designated as shown in FIG. 4A, it has the meaning as shown in FIG. 4B. That is, a line segment projecting inward perpendicular to each side shows the same plane as the reference shape, and in the direction from this line segment to another line segment, another line segment continues rightward with respect to the end point of each line segment. When it is performed, it means a valley fold, and when it is continuous leftward, it is a mountain fold. The lengths a and b of the line segments excluding the above-mentioned line segments respectively correspond to the finished dimensions of the bent portion. Further, the intersection angles θ ₁ and θ ₂ of the respective line segments indicate the surface angles of the respective surfaces. Here, the bending shape Y is given to all sides of the reference shape X. However, when the bending shapes Y are all equal, the bending shape Y is given to one side, and the others are the same. It may be indicated.

Further, the material and thickness of the sheet metal to be processed are inputted from the input means 1 (step S3). After the reference shape and the bent shape are selected and the material and thickness of the sheet metal are input, the first developed view creating means 2 creates the first developed view (step S4). As shown in FIG. 5, a first developed view shows a bent plate 11 necessary for forming a cross-sectional shape specified by a bent shape, and a main plate 10 forming a main surface of a product specified by a reference shape. Are connected to each side of.

In the first developed view, the bent piece 11 is the main plate 1
0 is protruded over the entire length of each side. Therefore, the first
In the developed view, when the inner angle of each vertex of the main plate 10 exceeds 180 degrees, the bent pieces 11 overlap each other. Therefore, as shown in FIG. 6, the width of the bent piece 11 is adjusted so that such an overlapping portion is not formed. That is, the width of the bent piece 11 is reduced by the dimension δL from the vertex where the bent piece 11 overlaps. The dimension δL is determined by the protrusion dimension F of the bent piece 11, the inner angle φ of the vertex of the main plate 10, and the value α corresponding to the thickness of the sheet metal. That is, δL = L ₁ −L ₂ = F / tan ｛180 ° − (φ /
2) It becomes｝ + α. Also, the inner angle of the vertex of the main plate 10 is 18
If the angle is within 0 degree, the bent piece 11 is displayed on the first development view.
Do not overlap, but taking into account the thickness of the sheet metal as shown in FIG.
The width of the bent piece 11 is reduced from the vertex by the value α. That is, δL = α.

By the way, in the first developed view, the bent piece 11
Even when the bent pieces 11 are not overlapped with each other, when the bending process is performed on each bent piece 11, an overlapping portion may be generated between the bent pieces 11. For example, when the first developed view is shaped as shown in FIG. 8 and each bent piece 11 is bent at two places, as shown in FIG. If both of the bent portions are mountain-folded or valley-folded, the bent pieces 11 will overlap after bending. Therefore, FIG.
As shown in (a), the notch 12 is provided in the bent piece 11 so as to prevent the bent piece 11 from overlapping. The width d of the notch 12 is determined by a function g whose function value is determined by the protrusion dimension a of the tip piece 11 a forming the inner flange of the product in the bent piece 11 and the inner angle φ of the vertex of the main plate 10. g
It is determined in the form of (φ, a). On the other hand, as shown in FIG. 10, when one of the two bent portions of the bent piece 11 is a mountain fold and the other is a valley fold, the notch portion 12 is not formed.

As described above, it is possible to obtain a second developed view in which the bent pieces 11 are prevented from overlapping based on the first developed view (step S5). When bending is performed in accordance with the second developed view obtained in this manner, an error occurs in a finished dimension due to extension at a bent portion. Therefore, the dimension calculating means 6 calculates the elongation amount δ when the bent portion is bent, based on the constant ρ defined by the material, the plate thickness t, and the bending angle θ (see FIG. 9B). (Step S6). In the dimension calculation means 2, the second
The dimension based on the finished dimension given to the developed view is corrected by the calculated elongation δ (step S7). That is, assuming that the finishing dimensions are set as shown in FIG. 11A, the dimensions H ₁ , H ₂ , W ₁ , and W ₂ are calculated as shown in FIG.
As shown in (b), dimensions H ₁ -δ, H ₂ -δ, W ₁
−δ, W ₂ −δ. After the dimensions are corrected in this manner, the developed data is output to the output unit 4 as a developed view (step S8). Here, steps S1 and S2 may be after step S3.

[0013]

According to the present invention, as described above, the drawing is performed with the shape of the main surface of the product as the reference shape, and the cross-sectional shape of the portion to be bent is drawn as the bending shape. By combining the shape and the bending shape, the development of the product can be obtained.Therefore, it is possible to easily create the development of various shapes by simply drawing the reference shape and the bending shape. To play. The method further includes a step of correcting the first development view so that the bending pieces do not overlap with each other based on the first development view in a state where the bent pieces corresponding to the bent shape are connected to each side of the reference shape. Therefore, there is an advantage that a development view can be created only by a simple operation of drawing a reference shape and a bent shape. Furthermore, the amount of elongation of the bent portion is determined by the material and thickness of the sheet metal, and the dimension given by drawing the base shape and the bent shape based on the finished dimensions is corrected by the amount of elongation. Drawing is also effective in that dimensions of each part in consideration of the amount of elongation are automatically obtained, and optimal dimensions are set to obtain a product having a desired dimension.

[Brief description of the drawings]

FIG. 1 is an operation explanatory diagram showing a processing procedure of an embodiment.

FIG. 2 is a block diagram of an embodiment.

FIG. 3 is a diagram illustrating a drawing example of a reference shape and a bent shape in the embodiment.

FIG. 4A is a diagram showing a reference shape and a bent shape in the embodiment, and FIG. 4B is a perspective view showing a part of a product corresponding to FIG.

FIG. 5 is a diagram showing an example of a first development view in the embodiment.

FIG. 6 is a diagram illustrating an example of avoiding overlapping of bent pieces in the embodiment.

FIG. 7 is a diagram illustrating an example of a portion where bent pieces do not overlap in the embodiment.

FIG. 8 is a diagram showing an example before considering an overlapped portion after bending in an embodiment.

FIG. 9A is a diagram showing an example of a second developed view in which no overlapping portion is formed after bending, and FIG. 9B is a cross-sectional view of a main part showing an example of a shape after bending.

FIG. 10 is a sectional view of a main part showing an example of a shape after bending.

11A is a diagram illustrating a state in which finishing dimensions are set in the example, and FIG. 11B is a diagram illustrating a state in which the amount of elongation is corrected in the example.

FIG. 12 is a diagram showing an example of a method for setting dimensions in a conventional example.

FIG. 13 is a diagram showing an example of a conventional development view.

14A is a diagram illustrating an example of a development view that cannot be handled by the conventional example, and FIG. 14B is a diagram illustrating an example of a product that cannot be handled by the conventional example.

[Explanation of Signs] 1 Input means 2 First development view creation means 3 Second development view creation means 4 Dimension calculation means 5 Output means

Claims (1)

(57) [Claims] 1. A process of drawing a shape of a main surface of a product to a reference shape with a fixed scale relative to a finished size, and a method of drawing a bent shape, which is a cross-sectional shape of a portion to be bent, on each side of the reference shape. A process of drawing with a fixed scale to the finished size, a process of inputting a material and a thickness of a sheet metal to be bent, and a process of connecting a bent piece corresponding to a bent shape to each side of the reference shape to perform a first development A process of creating a diagram, a process of creating a first developed view and a second developed view in which the first developed view is modified so that no overlapping portion is formed between bent pieces after bending, A step of obtaining an elongation amount of the bent portion based on the thickness, and a step of correcting a dimension given to the second development view based on the obtained elongation to obtain a target development view. A feature of this method is to automatically create a development view for bending.