JP3126335B2 - Sheet metal model development method in sheet metal CAD / CAM system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to computer aided design (CAD) systems and computer aided manufacturing (CA).
M) The present invention relates to a sheet metal CAD / CAM system configured to cooperate with each other and handle sheet metal products. In particular, a complicated operation input for an operator is removed, and a sheet metal model representing the geometric shape of the sheet metal product is directly obtained. The present invention relates to a sheet metal model expanding method in a sheet metal CAD / CAM system that can be expanded.

[0002]

2. Description of the Related Art An example of a procedure for developing a sheet metal model in a conventional sheet metal CAD / CAM system will be described with reference to FIG. Here, the sheet metal model refers to a solid model in which all surfaces including the outer surface, the inner surface, and the plate thickness surface that constitute the geometric shape of the sheet metal product are three-dimensionally expressed. 7, as shown in FIG. 7, means to generate a shape of a developed surface, which is a stage before a bending process, from a sheet metal model equivalent to a real model representing the geometric shape of a sheet metal product.

First, in step S101 of FIG.
The operator independently creates the shape of each surface in two dimensions while referring to the three surface drawings drawn using the CAD system.

Next, in step S102 of FIG.
The operator sequentially connects a plurality of surfaces by inputting an instruction to combine a pair of sides of each surface adjacent to each other. At this time, for example, when the surfaces adjacent to each other at a certain angle are continuous with each other, the operator sets the elongation value of the sheet metal work from the constraint conditions such as the bending angle between the two surfaces, and also sets the elongation value on both surfaces. Place them at a certain distance that is considered.

[0005] When the surface synthesis for connecting all the surfaces is completed, in step S103 in Fig. 8, the operator deforms the connection between the surfaces to set the outer shape to one closed path. At this time, a bending line is added to the connection portion between the surfaces, and a sheet metal development is created in the above procedure.

[0006]

However, the above-described sheet metal developing method in the conventional sheet metal CAD / CAM system includes many procedures that require an operator's hand, and the number of steps required for the development tends to be large. There was an inherent problem to be solved.

[0007] In view of such a situation, there has been a long-awaited desire among concerned parties to develop a new sheet metal developing method capable of directly developing a sheet metal model without bothering the operator.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and it is an object of the present invention to provide a sheet metal CAD / CAM system capable of directly developing a sheet metal model by eliminating complicated operation input for an operator. An object of the present invention is to provide a sheet metal model developing method.

[0009]

In order to solve the above-mentioned problems, the invention according to claim 1 uses a computer-aided design (CA).
D) Sheet metal CAD which is configured in cooperation with the system and a computer assisted manufacturing (CAM) system and handles sheet metal products.
In the / CAM system, with reference to the thickness of the sheet metal model representing the geometric shape of the sheet metal product, a pair of general surfaces facing each other across the sheet thickness portion among a plurality of surfaces constituting the sheet metal model; A thick part recognizing step of separately recognizing the thick face and a pair of general faces recognized in the thick part recognizing step, and generating an intermediate face from which the thick component is removed by referring to the pair of general faces. Surface generation step, a bending surface recognition step of recognizing a bending surface to be bent among the intermediate surfaces generated in the intermediate surface generation step, and at least the bending surface recognized in the bending surface recognition step, An elongation value obtaining step of obtaining an elongation value of the bent surface with reference to parameters determined from constraint conditions including a bending angle, a radius dimension of an inner radius, and a material of the sheet metal work; Connection between each surface And a face-to-face connection state search step of creating a face-to-face connection relation table containing the connection state between the faces based on the search result, and when a plurality of faces constituting the intermediate face are developed A developed shape calculating step of calculating the shape of the partially developed surface, and a partially developed surface of the shape calculated in the developed shape calculating step based on the inter-plane connection relation table created in the inter-face connection state searching step. An inter-plane line that generates an entire developed surface whose outer periphery is one closed path by removing a line segment existing between the partial developed surfaces generated in the developed surface generation process and the developed surface that is sequentially generated. And a step of removing the sheet metal model.

According to the first aspect of the present invention, first, in the sheet thickness portion recognition step, referring to the sheet thickness dimension of the sheet metal model representing the geometric shape of the sheet metal product, among the plurality of surfaces constituting the sheet metal model, A pair of general surfaces facing each other across the plate thickness portion and the plate thickness surface are separately recognized.

In the intermediate plane generation step, an intermediate plane from which the thickness component has been removed is generated with reference to the pair of general planes recognized in the thickness part recognition step.

In the bending surface recognition step, a bending surface to be bent is recognized from among the intermediate surfaces generated in the intermediate surface generation step.

In the elongation value obtaining step, the bending surface recognized in the bending surface recognition step is referred to at least by parameters determined from constraint conditions including a bending angle, a radius dimension of the bending R, and a material of the sheet metal work. Then, the elongation value of the bending surface is obtained.

In the inter-plane connection state search step, a connection state between the respective planes is searched for a plurality of planes constituting the intermediate plane, and an inter-plane connection including the connection state between the respective planes based on the search result. Create a relationship table.

In the developed shape calculation step, the shape of the partially developed surface when the plurality of surfaces constituting the intermediate surface are developed is calculated.

Further, in the developed surface generation step, a partial developed surface of the shape calculated in the developed shape calculation step is sequentially generated based on the inter-plane connection relation table created in the inter-plane connection state search step.

Then, in the inter-plane line segment removing step, by removing the line segment existing between the partial developed planes generated in the developed plane generating step, an entire developed plane having an outer periphery as one closed path is generated. .

As described above, according to the first aspect of the present invention, the sheet metal model itself representing the geometric shape of the sheet metal product is used as it is, and the thickness portion recognition, the intermediate plane creation, the bending surface recognition, the elongation value acquisition, the surface Search for connection state, calculation of expanded shape, generation of expanded surface,
And the unfolding process including the removal of inter-plane line segments is performed sequentially, so that the sheet metal model has the correct geometric shape as a sheet metal product, regardless of the type of system used to create the sheet metal model, and Thus, the complicated input operation by the operator can be eliminated, and the sheet metal model can be directly developed.

Further, according to the first aspect of the present invention, since the development is performed using the sheet metal model representing the geometrical shape of the sheet metal product as it is, the development cannot be performed due to an erroneous operation input by the operator such as a wrong composite position of the surface. Can be avoided beforehand.

Further, according to the first aspect of the present invention, since the development is performed using the sheet metal model representing the geometrical shape of the sheet metal product as it is, a free-form surface which can only obtain approximate dimensions by the conventional method can be obtained. It is possible to accurately reproduce a portion that becomes a free curve by developing.

Further, the invention of claim 2 is characterized in that the intermediate plane generating step generates an intermediate plane at a position which is at an equal distance from both of the pair of general planes recognized in the plate thickness part recognition step. And

According to the second aspect of the present invention, when the following processing steps such as recognition of a curved surface are performed based on a general surface without creating an intermediate surface, the radius dimension of the bend R becomes zero. However, there is no corresponding surface in the bent portion, which may hinder the performance of the processing step. On the other hand, when each processing step is executed on the basis of the intermediate plane, the bending R In the case where the radius dimension of is zero, a surface is created in the same manner as the other parts, so that a situation that hinders the execution of each processing can be avoided beforehand, and the flow of each processing is simplified. be able to.

Furthermore, the invention of claim 3 is characterized in that the elongation value of the bending surface obtained in the elongation value obtaining step can be set and input by an operator.

[0024] The invention of claim 4 is characterized in that a bending line generating step of generating a bending line at an intermediate position of a bending surface is added before the inter-plane line segment removing step.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A sheet metal CAD according to the present invention will be described below.
An embodiment of a sheet metal model expanding method in the / CAM system will be described in detail with reference to the drawings.

FIG. 1 is a flowchart showing a schematic procedure of a sheet metal model expanding method according to the present invention, and FIGS.
FIG. 6 is a state transition diagram used to supplementally explain a schematic procedure of the sheet metal model expanding method according to the present invention. FIG. 6 is a schematic block configuration diagram of a sheet metal CAD / CAM system to which the sheet metal model expanding method according to the present invention is applied. It is.

First, a sheet metal CAD / CAM system to which the sheet metal model expanding method according to the present invention is applied will be described with reference to FIG.
The explanation will be given with reference to FIG.
D) Sheet metal CAD which is configured in cooperation with the system and a computer assisted manufacturing (CAM) system and handles sheet metal products.
The / CAM system 1 includes a CAD system 3 and a CAM system 5.

The CAD system 3 includes a three-dimensional design device (hereinafter referred to as a “3D design device”) 7, a graphic display device 9 such as a graphic display, and a graphic device such as a keyboard connected to the 3D design device 7. Referring to the operation input device 11, the position input device 13 such as a mouse and a light pen, and CAD data including drawing information drawn by using the 3D design device 7, a paper model or a sheet metal model of a sheet metal product is created. Paper model / sheet metal model creation device 15
And a paper model / sheet metal model storage device 1 that stores the paper model and the sheet metal model created by the paper model / sheet metal model creating device 15 in a database and stores them.
7 are provided.

The CAM system 5 includes an NC processing data creation device 19 for creating NC processing data,
A graphic display device 21 such as a graphic display, a graphic operation input device 23 such as a keyboard, a position input device 25 such as a mouse and a light pen, and an NC processing data generating device 19 connected to the processing data generating device 19. Referring to the input CAD data, a paper model / sheet metal model creation device 27 for creating a paper model or a sheet metal model of a sheet metal product, and a sheet metal model created by the paper model / sheet metal model creation device 27 are developed and developed. The apparatus is provided with a sheet metal model automatic development device 29 for creating a drawing, and a paper model / sheet metal model storage device 17 for storing the paper model and the sheet metal model created by the paper model / sheet metal model creation device 27.

The paper model / sheet metal model storage device 17 is connected to a local area network such as Ethernet, which connects the CAD system 3 and the CAM system 5 so that data can be exchanged with each other. 3 and the CAM system 5. This allows
In both the CAD system 3 and the CAM system 5, access to the paper model and the sheet metal model stored in the database stored in the paper model / sheet metal model storage device 17 is permitted to access such as reading and writing of a corrected portion. .

The NC machining data created by the NC machining data creation device 19 of the CAM system 5 is, for example, NCT
It is supplied to a group of NC processing machines such as a processing apparatus 31, a laser processing apparatus 33, an NCT / laser combined processing apparatus 35, and a bending processing apparatus 37. In the NC processing machine group, cutting and punching of a sheet metal work according to the NC processing data are performed. It is configured to obtain a desired sheet metal product through sheet metal processing such as bending.

Next, a schematic procedure of a sheet metal model expanding method in the above-described sheet metal CAD / CAM system will be described with reference to a state transition diagram shown in FIGS. 2 to 5 and a flowchart shown in FIG. The sheet metal model expanding method according to the present invention is executed by being applied to the sheet metal model automatic expanding device 29 of the sheet metal CAD / CAM system 1.

First, the sheet metal model automatic developing device 29 converts, for example, the sheet metal model shown in FIG. 2A to be developed from among the sheet metal models stored in the database stored in the paper model / sheet metal model storage device 17. Referring to the thickness of the sheet metal model representing the geometric shape of the read and read sheet metal product, of the plurality of surfaces constituting the sheet metal model, as shown in FIG. A thick part recognition process for separately recognizing a pair of general faces and a thick face that face each other is executed (step S1).

Next, as shown in FIG. 3A, the sheet metal model automatic developing device 29 removes the sheet thickness component with reference to the pair of general surfaces recognized in the sheet thickness portion recognition processing in step S1. An intermediate plane generating process for generating the generated intermediate plane is executed (step S2). In this intermediate plane generation processing, step S1
An intermediate plane is generated at a position at an equal distance from both of the pair of general planes recognized in the plate thickness part recognition processing.

At this time, the number of faces generated by removing the thickness component is significantly reduced as compared with the case where the sheet metal model is directly handled. By sequentially executing the following processing steps as a basis, the number of processing steps in each processing step can be significantly reduced. Further, as an effect accompanying execution of each processing step based on the intermediate plane, for example, when each processing step is executed based on a general plane without creating an intermediate plane, an inner radius R (radius of bending R) In the bent portion where the value of (dimension) is 0, there is no corresponding surface, which may hinder the execution of the processing. On the other hand, when each processing step is executed based on the intermediate surface, In the case where the R value becomes 0, a surface is created in the same manner as the other portions, so that a situation that hinders the execution of each process can be avoided beforehand, and the flow of each process can be reduced. It can be simplified.

In the intermediate plane generation processing in step S2, an example will be described in which an intermediate plane is generated at a position at an equal distance from both of the pair of general planes recognized in the plate thickness portion recognition processing in step S1. However, the present invention is not limited to this form. For example, it is possible to adopt a form in which an intermediate plane is generated at an arbitrary position between a pair of general planes according to a sheet metal product shape.

Next, as shown in FIG. 3B, the sheet metal model automatic unfolding device 29 recognizes a bending surface to be bent from among the intermediate surfaces generated in the intermediate surface generating process in step S2. Execute bending surface recognition processing (step S
3).

Subsequently, the sheet metal model automatic developing device 29
As shown in FIG. 4 (a), regarding the bending surface recognized in the bending surface recognition processing in step S3, at least the bending angle, the radius dimension of the inner R (bending R), and the constraint including the material of the sheet metal work. An elongation value acquisition process for acquiring an elongation value of each bending surface is executed with reference to a parameter determined from the condition (step S4). The setting value input by the operator is allowed for the elongation value of the bending surface obtained in the elongation value obtaining process. At this time, for example, when the operator sets and inputs the elongation value of the bending surface, the other bending processing conditions are interactive, that is, the setting input value of the elongation value of the bending surface and the other bending processing conditions are interactive. Changed to work together. Conversely, for example, when an operator sets and inputs a certain bending condition, the elongation value of the bending surface is interactive, that is, the setting input value of a certain bending condition and the elongation value of the bending surface are mutually linked. It is changed as follows.

Next, as shown in FIG. 4 (b), the sheet metal model automatic development device 29 searches for the connection state between each of the plurality of surfaces constituting the intermediate surface generated in step S2. Then, based on the search result, an inter-plane connection state search process for creating an inter-plane connection relation table containing the connection state between the respective planes is executed (step S5).

Subsequently, the sheet metal model automatic development device 29
Determines whether or not all the planes constituting the intermediate plane generated in step S2 have been expanded. If the result of this determination is that all of the planes have not been expanded, the flow of processing is shifted to step S7. On the other hand, when all the surfaces have been developed, the flow of processing proceeds to step S9 (step S6).

If it is determined in step S6 that all the surfaces have not been developed yet, the sheet metal model automatic developing device 29 proceeds to step S2. A developed shape calculation process for calculating the shape of the partial developed surface when the surface is developed is executed (step S7).

Further, the sheet metal model automatic development device 29
Based on the inter-plane connection relation table created in the inter-plane connection state search process in step S5, as shown in FIG. 5A, the partially developed surface of the shape calculated in the expanded shape calculation process in step S7 is sequentially determined. The development plane generation processing to be generated is executed (step S8).

On the other hand, as a result of the determination in step S6, when it is determined that all the surfaces have been developed, the sheet metal model automatic developing apparatus 29 performs step S8 as shown in FIG.
By removing the line segment existing between the partial development surfaces generated by the development surface generation process of (1), the inter-plane line segment removal process of generating the entire development surface whose outer periphery becomes one closed path is executed (step S9). ), Terminating the sheet metal model development process. The inter-plane line segment removal processing in step S9 may be configured by adding a bending line generation processing for generating a bending line at an intermediate position of a bending surface, which is performed before this processing.

As described above, according to the sheet metal model developing method according to the present invention, the sheet metal model representing the geometrical shape of the sheet metal product itself is used as it is, and the thickness portion recognition, the intermediate surface creation, the bending surface recognition, and the elongation value of the elongation value are determined. Since the acquisition processing, the retrieval of the connection state between the planes, the development of the developed shape, the development of the developed plane, and the removal of the inter-plane line segment are sequentially executed, the sheet metal model may have the correct geometric shape as the sheet metal product. For example, the sheet metal model can be directly developed regardless of the type of system used to create the sheet metal model, and by eliminating complicated input operations by the operator.

Moreover, since the development is performed using the sheet metal model representing the geometrical shape of the sheet metal product as it is, it is possible to avoid a situation in which the development cannot be performed due to an erroneous operation input by the operator such as a wrong composite position of the surface. Can be.

Furthermore, since the development is performed using the sheet metal model representing the geometrical shape of the sheet metal product as it is, only the approximate dimensions can be obtained by the conventional method. The portion can be accurately reproduced.

Further, by using the sheet metal model expanding method according to the present invention, it is possible to construct a sheet metal CAD / CAM system capable of greatly reducing both the modeling man-hour on the design side and the man-hour for developing on the manufacturing side. Can be.

It is needless to say that the present invention is not limited to the above-described embodiment, but can be embodied in other modes by making appropriate changes.

[0049]

As described in detail above, according to the first aspect of the present invention, the sheet thickness model, the intermediate plane creation, the bending surface recognition, and the sheet metal model representing the geometric shape of the sheet metal product are used as they are. The expansion process including acquisition of elongation value, search of inter-plane connection state, calculation of expansion shape, generation of expansion surface, and removal of inter-plane line segment is executed sequentially, so that the sheet metal model has the correct geometric shape as the sheet metal product. Thus, the sheet metal model can be directly developed irrespective of the type of system used to create the sheet metal model, and by eliminating complicated input operations by the operator.

Further, according to the first aspect of the present invention, since the development is performed using the sheet metal model representing the geometrical shape of the sheet metal product as it is, the development cannot be performed due to an erroneous operation input by the operator such as a wrong composite position of the surface. Can be avoided beforehand.

Further, according to the first aspect of the present invention, since the development is performed using the sheet metal model representing the geometrical shape of the sheet metal product as it is, a free-form surface which can only obtain approximate dimensions by the conventional method can be obtained. It is possible to accurately reproduce a portion that becomes a free curve by developing.

According to the second aspect of the present invention, when the following processing steps such as recognition of a curved surface are performed based on a general surface without creating an intermediate surface, the bending radius is reduced.
There is no corresponding surface in the bent portion where the radius dimension of is 0, which may hinder the performance of the processing step. On the other hand, when each processing step is performed based on the intermediate plane, Even in the case where the radius dimension of the above-described bending R is 0, a surface is created in the same manner as the other portions, so that a situation that hinders the execution of each process can be avoided beforehand, and each process can be prevented. An extremely excellent effect that the flow can be simplified is achieved.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a schematic procedure of a sheet metal model expanding method according to the present invention.

FIG. 2 is a state transition diagram used for supplementarily describing a schematic procedure of a sheet metal model expanding method according to the present invention.

FIG. 3 is a state transition diagram used to supplementarily explain a schematic procedure of a sheet metal model expanding method according to the present invention.

FIG. 4 is a state transition diagram used for supplementarily describing a schematic procedure of a sheet metal model expanding method according to the present invention.

FIG. 5 is a state transition diagram used for supplementarily explaining a schematic procedure of the sheet metal model expanding method according to the present invention.

FIG. 6 is a schematic block configuration diagram of a sheet metal CAD / CAM system to which the sheet metal model expanding method according to the present invention is applied.

FIG. 7 is a diagram for explaining a sheet metal model expanding method according to a conventional example.

FIG. 8 is a diagram for explaining a sheet metal model expanding method according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sheet metal CAD / CAM system 3 CAD system 5 CAM system 7 3D design device 9 Graphic display device 11 Graphic operation input device 13 Position input device 15 Paper model / sheet metal model creation device 17 Paper model / sheet metal model storage device 19 NC processing data creation Apparatus 21 Graphic display device 23 Graphic operation input device 25 Position input device 27 Paper model / sheet metal model creation device 29 Sheet metal model automatic development device 31 NCT processing device 33 Laser processing device 35 NCT / laser combined processing device 37 Bending device

Claims (4)

(57) [Claims] 1. A sheet metal CAD / CAM system configured to cooperate between a computer assisted design (CAD) system and a computer assisted manufacturing (CAM) system and handling a sheet metal product, wherein a sheet metal model representing a geometric shape of the sheet metal product. A thick part recognizing step of separately recognizing a pair of general faces facing each other across a thick part and a thick face among a plurality of faces constituting the sheet metal model with reference to the thickness dimension. An intermediate plane generating step of generating an intermediate plane from which the thickness component has been removed with reference to a pair of general planes recognized in the plate thickness part recognizing step, and an intermediate plane generated in the intermediate plane generating step A bending surface recognition step of recognizing a bending surface to be bent; and at least a bending angle, a radius dimension of the bending R, and a material of the sheet metal work for the bending surface recognized in the bending surface recognition step. An elongation value obtaining step of obtaining an elongation value of the bending surface with reference to a parameter determined from the constraint condition, and, for a plurality of surfaces constituting the intermediate surface, searching for a connection state between the surfaces, A face-to-face connection state searching step of creating a face-to-face connection relation table containing the connection state between the faces based on the search result; and a shape of a partially developed face when the plurality of faces constituting the intermediate face are developed. And an expanded surface generation step of sequentially generating a partially expanded surface of the shape calculated in the expanded shape calculation step based on the inter-plane connection relation table created in the inter-plane connection state search step. And an inter-plane line segment removing step of generating an entire developed plane having an outer periphery as one closed path by removing a line segment existing between the partial developed planes generated in the developed plane generating step. Includes composed The method sheet metal model development in sheet metal CAD / CAM system, characterized in that deploying the sheet metal model. 2. The intermediate plane generating step of generating an intermediate plane at a position at an equal distance from both of the pair of general planes recognized in the plate thickness part recognition step.
3. A sheet metal model expanding method in the sheet metal CAD / CAM system according to item 1. 3. The method for developing a sheet metal model in a sheet metal CAD / CAM system according to claim 1, wherein the elongation value of the bending surface obtained in the elongation value obtaining step is allowed to be set and input by an operator. . 4. A front The interplanar segment removal step, sheet metal according to claim 1, characterized in that it is constituted by adding a bend line generating step of generating a bend line to an intermediate position of the bent surface CAD
/ Development method of sheet metal model in CAM system.