JP2010049381A - Nc data creation system with template software inserted therein for converting three-dimensional cad model geometrical element into machining program sentence - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To create highly precise/super-fine and smooth machining data including a circular-arc by carrying out vector processing instead of polygon processing in creating the NC data of a three-dimensional CAD shape model. <P>SOLUTION: Template software is prepared between an upstream three-dimensional CAD and a downstream three-dimensional automatic programming system, which is configured to create a machining program by extracting and automatically converting three-dimensional CAD data having potential point information of node points where mesh curves of a CAD model cross each other into the machining program by a mouse operation. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an NC cutting data creation method for a three-dimensional CAD shape model of a shaped part, and directly extracts nodal point geometric element vector information intersecting geometric element curves woven in a mesh shape constituting the CAD shape model from CAD, The present invention relates to a template software insertion NC data creation system for converting CAD shape model information into machining program information in order to improve machining accuracy and smoothness by using this as a shaping part shape machining program.

  In creating NC data for cutting from a three-dimensional CAD shape model of a modeled part, the modeled part is designed with three-dimensional CAD, and NC data is created with three-dimensional CAM.

  In the conventional CAD / CAM, the model of the shaped part designed by 3D CAD for machining data creation is reproduced in the CAM modeler unit via the translator (software that correctly transfers the CAD data to the CAM modeler). The processed surface of the curve display woven in a mesh pattern is subjected to surface processing polygon processing, and the shape of the three-dimensional CAD shape model is expressed by a group of fine triangular patches to create NC machining data.

  The geometric structure figure when designing a shape model with 3D CAD is roughly divided into regular solids and curved surfaces, and the geometric elements of regular solids are combinations of 2D and 3D straight lines, 2D circles and 2D arcs. It is an aggregate display, and the geometric elements of the curved surface are displayed as a combined aggregate of two-dimensional and three-dimensional straight lines.

  In conventional 3D CAD / CAM, when creating NC data for regular 3D modeling of a shape model, the geometric element component of a regular 3D is a 2D geometric element, but software that directly converts to 2D CAM data is available. In addition, since there is no idea of converting to a two-dimensional circle and arc in a three-dimensional CAM, there is no command, and all the circles and arcs are divided into hyperpolygons. In NC data creation, the CAD drawing command is used to switch to the three-view drawing display, print it out as a drawing, and create a new design drawing with two-dimensional CAD based on the three-view drawing displayed. Thus, NC machining data is created by a three-dimensional machining 2.5-dimensional CAM.

  NC data creation for modeling a curved surface in a 3D CAD shape model was created by executing a polygon processing after reproducing the CAD design shape model in the 3D CAM modeler, and the curved surface was sliced by cutting a horizontal plane at equal intervals. NC machining data creation method similar to 2.5-dimensional contour cutting is adopted as cutting processing data using contour cutting.

  The current CAD / CAM NC machining data creation uses many contour cutting NC machining data including efficiency improvement in the machine structure of the NC machine, so the boundary between 3D curved patches may be blurred. Polishing work for manual correction and smoothing is added in the post-process.

  In the creation of NC machining data for 3D CAD / CAM, even though the improvement of machining accuracy and smoothness is required by system introduction users, the resolution at the time of machining data conversion is minimized even in provisional measures. There was a problem that the fundamental solution was not clarified.

  When creating 3D CAD / CAM NC machining data, when reproducing a CAD design shape model in the 3D CAM modeler unit, the surface of the curved display weaves in a mesh pattern is subjected to polygon processing for surface processing to form a fine triangular patch group Therefore, there has been a problem that the conversion creation function of the 2D circle and 2D arc possessed by the NC language cannot be used.

  Further, in reproducing the CAD design shape model in the three-dimensional CAM modeler unit, the surface of the curved display shape woven in a mesh shape is only subjected to surface processing polygon processing to form a fine triangular patch group. Therefore, in the 3D CAD design, the mesh-like curves of the shape model are only used for polygon processing, and are not effectively used for NC machining data creation. There was a problem that NC machining data for continuous cutting could not be created.

  Furthermore, since the mesh-like curve of the shape model created in the 3D CAD design is used only for polygon processing, in order to improve accuracy, processing accuracy, slipperiness, etc. in curved patch units. There was a problem that it was difficult to contribute.

  In order to solve the above-mentioned problem, the invention according to claim 1 is characterized in that the three-dimensional CAD is used to obtain potential point information of the intersecting nodes of the curves displayed in a mesh pattern in the shape model representation of the modeling part designed by the three-dimensional CAD. The gist is that template software that directly extracts from data and creates a machining program is provided between the upstream three-dimensional CAD and the downstream three-dimensional automatic professional.

  In order to solve the above-mentioned problem, the invention according to claim 2 is the NC data creation method according to claim 1, wherein the nodal point geometric elements intersecting the geometric element curves woven in a mesh shape constituting the three-dimensional CAD shape model of the shaped part Is converted into vector information, and includes an implementation of an NC machining program for curved patch machining or curved machining.

  In order to solve the above-mentioned problem, the invention according to claim 3 is the NC data creation method according to claim 1 or claim 2, wherein a curve that weaves a cutting area in a mesh shape is created by a three-dimensional CAD shape model of a shaped part. The horizontal and vertical rows and vertical and vertical curved surface patches make it possible to utilize the know-how cultivated by the program engineer to make one set of single curved surface patches, or a group of curved surface patches and horizontal and vertical rows. It is possible to freely select the cutting area that can make use of experience values such as the cutting area, cutting direction, cutting method, etc. of the curved surface patch group and the matrix-shaped curved surface mesh that combines horizontal and vertical rows and columns. And

  In order to solve the above-mentioned problems, the invention described in claim 4 is intended to achieve high accuracy and high accuracy by utilizing the experience and know-how related to cutting that has been cultivated for many years in NC machining data creation. The NC data creation upstream part is a three-dimensional CAD shape modeling part, the intermediate part is a template software part, the downstream part is an NC data creation part, and a three-dimensional automatic program is arranged in this downstream part. With this, the know-how of cutting technology cultivated by machining engineers can be freely selected in the intermediate part of the template software part and the downstream part of the three-dimensional automatic professional part, and a system configuration capable of giving detailed machining instructions was considered. That is. The gist of this is that the NC data creation system employs a technique that leads to distributed processing operation of advanced computer utilization techniques.

  According to this invention, the machining program to be input to the 3D automatic professional automatically creates a machining program for NC machining from the 3D CAD shape model of the modeled part in the template software without manual input by the machining engineer. It becomes possible.

  Also, for regular solid shapes of 3D CAD shape models, 2D circle and arc conversion program commands are further automatically created by extracting NC machining programs directly from CAD shape data. The processing data volume is drastically reduced by the compression processing and NC machine operation effect, and the smoothness of the machined surface is improved.

  Further, with respect to the curved surface of the three-dimensional CAD shape model, the accuracy and the smoothness of the machined parts are improved by the vector value conversion of the accurate and faithful shape data.

    In the creation of the three-dimensional CAD shape model, a technique that does not change anything from the modeling procedure of the shaped part in the conventional three-dimensional CAD is adopted. However, the conventional 3D CAM is a modeler function part of the CAM for machining data conversion, and NC data is created by utilizing the redraw display function of the CAD shape model. It has no CAD model redraw display function. Therefore, the template software 15 has a functional structure in which the vector information of the nodes where the curves woven in a mesh shape of the three-dimensional CAD shape model intersect is replaced with the machining program information.

Embodiment 1 FIG.
FIG. 2 relates to the NC data creation of the 3D CAD shape model 11 of the template software insertion NC data creation system. Considering the cutting theory of cutting a shaped part, 2.5D cutting of a regular solid 12 is performed. And the three-dimensional cutting of the curved surface 13, and there is a difference in the processing data structure. In the CAD expression of the three-dimensional CAD shape model 11, the nodal point vector information at which the curves interwoven in a mesh shape intersect is used. The template 15 executes an operation of automatically replacing the machining program information.

Embodiment 2. FIG.
In FIG. 2, the regular solid 12 and the curved surface 13 of the three-dimensional CAD model 11 of the template software insertion NC data creation system are both shown in the first embodiment. The 3D CAD shape model information is replaced with machining program information, but it is possible to extract a curved patch freely selected from the CAD model shape, and to be able to command machining information cultivated by a machining engineer. . Therefore, an arbitrary curved surface patch of the three-dimensional shape model can be extracted and a free processing instruction can be given. FIG. 3 is an example of an expanded display diagram of a general three-dimensional CAD shape model. The template software 15 includes a total of 12 sets of quadrangular curved patches in this curved patch group 20, in which quadrangular curved patches are arranged in three horizontal and four vertical. Either can be extracted as a program for processing the curved surface patch 21 or 22 shown in FIG. 4 alone, can be extracted as a program for processing the curved surface patch group 23 or 24 shown in FIG. 5, and further the entire curved surface patch group 20 is processed. It can also be extracted as a program to do. In this manner, the template software 15 can freely select extraction of a machining program that the processor is good at from the three-dimensional CAD shape model.

Embodiment 3 FIG.
FIG. 6 shows three-dimensional CAD shape data that is the basis of the template software insertion NC data creation system that is the basis of the first embodiment and the second embodiment of the present invention, and the curves intersect with each other in a mesh pattern. In the relationship between the absolute coordinate value (X, Y, Z) of the nodal point that becomes the vector value of the nodal point O, that is, the position vector value, and the tangential direction vector, that is, the position vector of the direction vector (δx, δy, δz) and the direction vector, Segment point information with a configuration that lends one set of direction vectors to one position vector and potential point information with a configuration that lends two sets of direction vectors to one position vector are configured. Use and potential of this segment point information Describe the use of point information. First, tangent vector lending at a three-dimensional point is a state in which a point P is set on an arbitrary surface of a right-handed coordinate system globe having a vertical axis in FIG. Considering the core O (X0, Y0, Z0) of the globe, if the direction of the straight line OP is expressed by a direction cosine, A (δX, δY, δZ) is obtained. If U = cosα, V = cosβ, and W = cosγ where α, β, and γ are the straight line OP and the X, Y, and Z axes, respectively, (U, V, W) is the cosine of the direction of the straight line OP. (Fig. 8) is a fact of common knowledge. A mode in which the point O is aligned with the nodal point position and the point P is matched with the tangent vector of the three-dimensional CAD shape model may be automatically implemented using template software. This allows all of the following things to be processed automatically.

  The basis of the curved surface patch is a rectangular curved surface patch, and the four corner points of this patch are matched with the nodes of the 3D CAD shape model. A patch can be expressed. In the present invention, this UV is expressed as A instead of U and B as V instead of V. FIG. Applying the vector of the corner points of the four corners of the square □ PQRS in FIG. 7, that is, the potential point information, the template software becomes a shape program that processes a square curved surface patch. This is a patch processing program. All of the curve cutting program and curved surface patch cutting program of the present invention are information on passing points like the CAD modeling curve creation, and unlike the control point input such as general B-spline curved surface creation, the three-dimensional CAD. It is a nodal point itself, not a control point, where the curves interwoven in a mesh form that constitute the shape model intersect. In the template software of the NC software creation system for template software of the present invention, in order to automatically replace the nodal point vector of the three-dimensional CAD shape model with the potential information, and to make this a machining program statement, this template software is a ball end mill. It needs to be shape data at the center of the tool, and is accompanied by a three-dimensional offset processing function. As can be understood from the above description, in the NC data creation system of the present invention, it is not necessary to perform surface processing of the CAD shape model, and only advanced use of only the nodal point potential point information of the CAD shape model is sufficient.

When cutting a 3D CAD shape model shaped part, processing data has been enormous in the past because of processing data creation by polygon processing, but the template according to the present invention automatically performs vector conversion of shape data. By creating a program, the amount of data is drastically reduced, and the three planes extending from G17 (XY plane), G18 (XZ plane), and G19 (YZ plane) are interpolated with circular arcs and NURBS curves to achieve high precision and ultra-smoothness. Can be processed.
Therefore, by utilizing the template software according to the present invention, an effect that a great contribution can be made to the machining industry is generated.

The flowchart figure which shows the whole function of this invention Internal function display diagram of FIG. Example of expanded display of a general 3D CAD shape model Arbitrary single curved surface patch example display diagram in FIG. Arbitrary surface patch group example display diagram in FIG. Tangent direction vector lending state diagram for position vector points used in the present invention A quadrangle curved surface patch with four points and direction vector loan diagram in A and B directions Direction cosine explanatory diagram

Explanation of symbols

20 curved surface mesh 21 curved surface patch 22 curved surface patch 23 curved surface patch group 24 curved surface patch group

(A) Segment point information (a) The segment point program statement describes the direction coordinate cosine description of the geometric angle display method for the absolute coordinate point of the position vector and the direction vector in one direction passing through the point.
Syntax (1 line 1 statement processing)
(X, Y, Z), A (I, J, K)
X: X value of position vector display (absolute coordinate value)
Y: Y value (absolute coordinate value) of position vector display
Z: Z value of position vector display (absolute coordinate value)
A: Direction vector display symbol I: δx value (relative coordinate value) of direction vector display
J: δy value (relative coordinate value) of direction vector display
K: δz value (relative coordinate value) of direction vector display
Note: If this segment point description method is adopted, all the straight lines, arcs and curves of graphic elements can be expressed, so this description method is used.

(B) Potential point information (b) The program statement of the potential point describes the direction cosine of the geometric angle display method with the absolute coordinate point of the position vector and the two direction vectors passing through the point.
Syntax (1 line 1 statement processing)
(X, Y, Z), A (I, J, K), B (P, Q, R)
X: X value of position vector display (absolute coordinate value)
Y: Y value (absolute coordinate value) of position vector display
Z: Z value of position vector display (absolute coordinate value)
A: A vector symbol
I: δx value of A vector (relative coordinate value)
J: δy value of A vector (relative coordinate value)
K: δz value of A vector (relative coordinate value)
B: B vector display symbol P: δx value of B vector (relative coordinate value)
Q: δy value of B vector (relative coordinate value)
R: δz value of B vector (relative coordinate value)
Note: 2 direction vector lending to potential point 1) A direction vector is the direction in which the tool travels cutting = for explanatory purposes, direction vector of main curve direction = base line direction 2) B direction The direction vector of the crossing curve that intersects the main curve = secondary curve = direction vector of the curve in which the tool picks and moves = cross line direction

Claims (4)

A geometry that interweaves a 3D CAD shape model of a modeled part in an NC data creation system that creates an NC machining program by extracting 3D CAD model geometric elements created by a 3D CAD system from the 3D CAD system. NC data creation, characterized in that it is expressed by a combination curve of elements, vector information of nodal point geometric elements that intersect the mesh of this curve is extracted directly from CAD data, and template software is inserted to convert it into machining program information system. Direction vector values (Δux, Δuy) in two intersecting UV directions at the position vector value (X, Y, Z) points of the vector information held by the intersecting nodes of the curves representing the three-dimensional CAD shape model of the molded part , [Delta] uz and [Delta] vx, [Delta] vy, [Delta] vz), the surface information is composed of a minimum of four sets of nodal point information, or 3 in the UV bi-directional (U or V direction vector) existing at the nodal point. 2. The template software insertion NC data creation system according to claim 1, wherein the system comprises dimension curve information. In order to extract a cutting region from a three-dimensional CAD shape model of a modeling part, when determining the size of the region, one set of quadrangular curved surface patches (four sets of nodal point information = potential point information) ) Simple curved surface patch information, horizontal line or vertical line curved surface patch group, or curved surface mesh information in which curved surface patches are arranged in a matrix, the expression of curves and curved surfaces is not used, and nodal point information is used. 3. The template software insertion NC data creation system according to claim 1 or 2, wherein the machining program command system is arranged in a matrix and performs numerical management control of the nodal point information amount. In order to deliver the shape data for creating NC machining data of 3D shape model data to an automatic professional in the NC data creation system that extracts the 3D CAD shape model geometric element of the modeling part and creates the NC machining program, A template software insertion NC data creation system characterized in that it is configured via a template software section for managing vector-based shape data conversion for NC machining and potential point information.

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