JP2004265050A - Measurement method for gap between component models and gap analysis model production method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for easily measuring a gap between component models to easily produce an analysis model for the gap. <P>SOLUTION: The surface of the component model by CAD data is divided into a plurality of face elements, contact decision is executed by use of a normal vector in each the divided face element, and a distance of the normal vector (contact 1-n) between the face elements forming the gap is measured. Thereby, the gap between the component models can be easily measured. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for measuring a gap between component models and a method for creating a gap analysis model.
[0002]
[Prior art]
In a process of flowing a raw material in a gap or processing a raw material, a gap between two part models is evaluated by various simulations using a CAD tool before a product is created. For example, evaluation of a gap in a mold into which raw materials are poured, evaluation of a gap to be filled with a heat insulating material of a refrigerator, evaluation of a gap formed in a pressed part, and evaluation of a gap formed in a mold are performed.
[0003]
In the evaluation of such a gap, since a method of creating an analysis model of the component itself using the surface data of the component model has conventionally existed, by using the analysis model of the component model itself, It was performed indirectly (for example, see Patent Document 1).
[0004]
[Patent Document 1]
JP-A-11-353501
[Problems to be solved by the invention]
However, in the method of indirectly evaluating the gap using the surface data of the component model, it takes enormous man-hours and time to recognize an analysis model corresponding to the gap. That is, even if the surface of the part model is divided into a plurality of elements, the part model based on the CAD data is eventually recognized as one large surface by the CAD calculation formula. When measuring, the distribution of the distance between the surfaces cannot be measured, and the calculation of the portion corresponding to the gap becomes very complicated and difficult. In addition, since the calculation is based on the surface data of the component model and does not use the gap model as it is, the accuracy of the gap analysis model indirectly recognized is low.
[0006]
The present invention has been made by paying attention to such a conventional technique, and provides a method of easily measuring a gap between component models and easily creating an analysis model of the gap.
[0007]
[Means for Solving the Problems]
According to the first aspect of the present invention, the surfaces of two or more component models based on CAD data are divided into a plurality of surface elements by a conversion tool, and a normal vector for each surface element is used to divide a surface of an opposing part model. This is a gap measurement method between component models, in which a contact determination is performed, and a gap between component models is measured by measuring a distance between normal vectors at contacts 1 to n.
[0008]
According to a second aspect of the present invention, there is provided a method for measuring a gap between component models, wherein the surface element is a polygon, an FEM mesh or a patch.
[0009]
According to a third aspect of the present invention, there is provided a method for measuring a gap between component models, wherein when a gap is measured, only a surface element targeted for the gap is colored by assigning a color distribution according to a measured distance. is there.
[0010]
According to a fourth aspect of the present invention, the surfaces of two or more component models based on CAD data are each divided into a plurality of surface elements by a conversion tool, and a normal vector for each surface element is used to divide a surface of an opposing part model. This is a method for creating a gap analysis model between component models, in which a contact determination is performed, only a surface element to be a gap is extracted, and a gap analysis model is created using the extracted surface element.
[0011]
A fifth aspect of the present invention is a method for creating a gap analysis model between component models, wherein the surface element is a polygon, an FEM mesh, or a patch.
[0012]
A sixth aspect of the present invention is a method for creating a gap analysis model between component models, characterized in that only the extracted surface elements are colored.
[0013]
【The invention's effect】
According to the first aspect of the present invention, the surface of the part model based on the CAD data is divided into a plurality of surface elements, and a contact determination is performed using a normal vector of each of the divided surface elements to form a gap. By measuring the distance of the normal vector (contact 1 to n) between the surface elements, the gap between the component models can be easily measured.
[0014]
According to the second aspect of the present invention, since polygons, FEM meshes, or patches are used as the surface elements for gap measurement, the surface data of the part model can be converted into a plurality of surface elements by a general conversion tool. .
[0015]
According to the third aspect of the present invention, since the color distribution according to the measurement distance is assigned to only the surface element targeted for the gap and colored, it is easy to visually recognize the measurement distance distribution of the gap. Become.
[0016]
According to the fourth aspect of the present invention, the surface of the part model based on the CAD data is divided into a plurality of surface elements, and a contact determination is performed using a normal vector of each of the divided surface elements. Since a gap analysis model is created by extracting only those surface elements, a gap analysis model between component models can be easily created.
[0017]
According to the fifth aspect of the present invention, since a polygon, an FEM mesh or a patch is used as a surface element for creating a gap analysis model, the surface data of the part model is converted into a plurality of surface elements by a general conversion tool. Can be.
[0018]
According to the invention of claim 6, since only the surface elements extracted for creating the gap analysis model are colored, it becomes easy to visually recognize the gap analysis model.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described with reference to FIGS. FIG. 2 shows two component models 1 and 2 existing on the CAD system. One part model 1 is a columnar body having a substantially elliptical cross section, and the other part model 2 is a rectangular parallelepiped.
[0020]
The measurement between the gaps S existing between the two component models 1 and 2 and the creation of the analysis model M will be described with reference to the flowchart of FIG. 1 and FIGS.
[0021]
First, two component models 1 and 2 forming the gap S are created as CAD data (step S1). Next, as shown in FIG. 3, the surfaces of the component models 1 and 2 are divided into a plurality of polygons 1a and 2a using a conversion tool (translator, converter, or the like) on the CAD system (step S2). The polygons 1a and 2a are polygons used for expressing a three-dimensional shape in three-dimensional computer graphics. In most cases, triangles are used for ease of calculation. For convenience, it is represented as a square and large. In addition to the polygons 1a and 2a, a mesh of FEM (finite element method) or a patch may be used.
[0022]
Then, using the surfaces of the polygons 1a and 2a, a normal vector perpendicular to the polygon surface (not shown) is generated in the direction opposite to the component thickness direction. If only the surface has no thickness, a normal vector is generated for both surfaces (step S3).
[0023]
Next, contact determination is performed using the generated normal vector (step S4). This contact determination is based on, for example, the number of normal vectors from another part model that contacts one polygon 1a and the number of normal vectors generated from the one polygon 1a that contacts another part model. judge. When the contact is 0, it is not regarded as the gap S (step S5). If it is not the gap S, it means that the normal vector is not headed toward the partner part models 1 and 2, and nothing is done (step S6). Here, “contact” means that “the normal vector hits one polygon of the other party” or “the normal vector has a projection point on the polygon surface of the other party”. .
[0024]
If the number of contacts is 1 or more (1 to n), it is determined that there is a gap S (step S7). The gap S formed between the two component models 1 and 2 can be directly measured from the measured distance of the normal vector (step S8). Therefore, when the number of contacts is one or more, the gap S between the objects is calculated from the starting point of the normal vector to the projection point on the mating polygon surface.
[0025]
Next, based on the measurement result, only the polygons 1a and 2a targeted for the gap S are assigned a color distribution according to the measurement distance and colored (step S9). This makes it easy to visually recognize the measured distance distribution of the gap S.
[0026]
Note that only the polygons 1a and 2a of the contacts 1 to n can be colored in a single color without measuring the distance of the normal vector (step S10).
[0027]
Then, as shown in FIG. 4, only the polygons 1a and 2a colored in step S9 or step S10 are extracted to make it easier to recognize the shape of the gap S three-dimensionally (step S11). Further, the periphery of the extracted polygons 1a and 2a is closed using processing software, and an analysis model M of the gap S as shown in FIG. 5 can be obtained (step S12).
[0028]
As described above, the contact determination is performed using the normal vectors of the polygons 1a and 2a divided into a plurality of parts, and only the polygons 1a and 2a that are the targets of the gap S are extracted to create the analysis model M of the gap S. It is easy to create the analysis model M of the gap S between the component models 1 and 2.
[0029]
Therefore, in the process of flowing the raw material into the gap S or in the process of processing the raw material, a preliminary evaluation of the product can be performed at an early stage by simulation using the created analysis model M, and the development period of the product can be shortened. This can contribute to improving the quality of the product, reducing the number of man-hours for trial production, and the like. For example, it is possible to analyze the flow of the resin, which is a raw material, in the gap of a mold for molding a resin molded part, and to apply the method to an analytical model of a heat insulating material such as a refrigerator, a pressed part, or a mold.
[Brief description of the drawings]
FIG. 1 is a flowchart showing a procedure of gap measurement and creation of a gap analysis model.
FIG. 2 is a three-dimensional view showing two component models on CAD data.
FIG. 3 is a three-dimensional view showing a state where the surface of a part model is divided into a plurality of polygons.
FIG. 4 is a three-dimensional view showing only polygons that are targeted for gaps.
FIG. 5 is a three-dimensional view showing an analysis model created by closing the periphery of a polygon to be a gap;
[Explanation of symbols]
1, 2 part model 1a, 2a polygon S gap M analysis model

Claims (6)

The surfaces of two or more part models (1, 2) based on the CAD data are respectively divided into a plurality of surface elements (1a, 2a) by a conversion tool, and a normal vector in each surface element (1a, 2a) is used. A contact model for the opposing part models (1, 2), and measuring the distance between normal vectors at the contacts 1 to n to measure a gap (S) between the part models. How to measure the gap between A method for measuring a gap between component models according to claim 1, wherein
A method for measuring a gap between component models, wherein the surface elements (1a, 2a) are polygons, FEM meshes or patches. A method of measuring a gap between component models according to claim 1 or 2,
When the gap (S) is measured, only the surface elements (1a, 2a) targeted for the gap (S) are colored by assigning a color distribution according to the measured distance. Method. The surfaces of two or more part models (1, 2) based on the CAD data are respectively divided into a plurality of surface elements (1a, 2a) by a conversion tool, and a normal vector in each surface element (1a, 2a) is used. The contact determination is performed on the facing part model, only the surface element (1a, 2a) targeted for the gap (S) is extracted, and the gap analysis model (M) is extracted using the extracted surface element (1a, 2a). Creating a gap analysis model between component models. A method for creating a gap analysis model between component models according to claim 4,
A method for creating a gap analysis model between component models, wherein the surface elements (1a, 2a) are polygons, FEM meshes or patches. A method for creating a gap analysis model between part models according to claim 4 or claim 5,
A method of creating a gap analysis model between component models, characterized in that only the extracted surface elements (1a, 2a) are colored.

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