JP4353689B2 - Method of creating machining path information in CAD / CAM apparatus and CAD / CAM apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for generating an NC program in a CAD / CAM device, and more particularly to a wire CAM device, and a process for generating machining path information for generating an NC program for machining a model from a three-dimensional model in the CAD / CAM device. The present invention relates to a method and apparatus for automating the process.
[0002]
[Prior art]
Conventional NC wire processing that cuts the workpiece in accordance with the direction of wire travel and discharges the workpiece into a predetermined shape by electric discharge between the wire attached to the wire CAM device or the like and the workpiece such as metal. In the machine, input / output data for the contour of the workpiece is created by the user or by dialog with the system each time. Some have been partially automated (for example, see Patent Document 1).
[0003]
[Patent Document 1]
JP 7-319529 A
[0004]
[Problems to be solved by the invention]
The conventional method of creating input / output data for the contour of a workpiece by the user or by interacting with the system has the following problems. First, in determining whether wire processing is possible, it is necessary for the operator to determine for each surface to be processed, which is complicated. In particular, it is easy to make a mistake in judging whether or not the taper stroke is within the limit of the wire inclination of the wire processing machine. Next, in the work of extending the surface so as to ride on the upper and lower program specifications, the surface is extended using the function of the three-dimensional CAD, but the function of the three-dimensional CAD is not a function intended only for wire processing. May not be created. Next, the cross-sectional line is the same, and it is not intended to create a continuous and non-branching path required by the wire CAM. Therefore, a non-continuous path or a branching path was created with a slight model error. Sometimes things need to be corrected. Next, in associating paths of upper and lower program specifications, associating curved surfaces becomes a problem. In the case of a curved surface, the path is a curve, but the curve is represented as a number of minute line segments for association. For this reason, the task of associating the upper and lower sides to represent the surface is a problem that even a skilled operator requires a huge amount of work.
[0005]
When creating from a curved line, the work flow is basically the same as that of a solid surface, so the amount of work increases as much as the surface work is performed.
[0006]
In addition, in order to create an NC program with a conventional wire CAM device, the operator must determine in what order to cut the machining shape in order to create a workpiece, and machining the recognized machining site. It was necessary to determine which of the inner and outer sides to be cut, which is the most basic judgment in the method, is the product shape and to give machining information to the CAM side.
[0007]
In the present invention, in order to process the target shape of the product shape of the above-described 3D model, as a piece of information to be passed to the wire CAM, the wire processing portion of the 3D model that conventionally had to be determined and created by the operator is recognized.・ Judgment work, 2D path of the upper and lower program specifications for wire processing the wire processable part of the 3D model according to its shape, and determination and processing of whether the shape is inside or outside the product shape The purpose is to automate the judgment of the order and the judgment of the processing start position by recognizing and judging the three-dimensional model. And it aims at fully automating from a three-dimensional model to processing by combining a wire CAM device.
[0008]
In addition, when creating a path for wire processing on a three-dimensional curve, only the operation of specifying the correspondence between curves that is necessary at the minimum to define the processing path for the part that was conventionally done manually The purpose is to do.
[0009]
[Means for Solving the Problems]
In view of the above object, the present invention For wire processing machines that move the upper and lower guides to move the wires stretched between these guides and perform processing by electric discharge between the wires and the workpiece A method of creating machining path information for generating an NC program for machining a model from a three-dimensional model in a CAD / CAM apparatus, wherein a surface 3 is obtained from a solid surface three-dimensional model of an indicated three-dimensional CAD. Dimensional surface type Start and end ridge lines that indicate the range of machining start and end of the boundary surface 3D model wire processing is performed by determining whether or not wire processing of the surface is possible based on the taper angle of the constituent curve in the wire feed direction and whether there is path interference in which the wire processing path cuts into the 3D model. From the process of automatically recognizing the parts that can be processed by the machine and the parts that can be processed by the wire processing machine, According to the NC program command of the guide Creates a wire processing path of program specifications indicating the movement of the program command height and the arbitrary shape command height, groups it into wire processing units, automatically recognizes the wire processing machine operation from the 3D model, and generates the processing path Machining path information in a CAD / CAM device comprising: a step of creating, and a step of setting a machining type based on information referred to by a three-dimensional model and setting a machining type of an appropriate wire And a CAD / CAM device thereof.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
First, wire processing as a technical background of the present invention will be described. FIG. 1 is a conceptual diagram of wire processing. The wire processing is a process in which a material is wire-cut by electrolytic action using the wire 101 as an electrode. When the NC program is executed on the wire processing machine (wire CAM device), the upper part is positioned so that the wire position is in the XY plane (program command height) and UV plane (arbitrary shape command height) specified in the NC program. The guide 102 and the lower guide 103 move so that the wire 101 moves along the wire processing path 100. In the section in which the wire has moved, line cutting is performed, and the shape is cut from the material by the continuous line cutting. Processing to cut the wire vertically is straight processing, processing to cut while tilting the wire at a certain angle is taper processing, processing to cut while tilting the wire so that the wire position on the specified XY surface UV surface is arbitrary This is called (4-axis) machining. A control command for obtaining the cutting shape from the material by controlling the upper and lower guides of the wire processing machine is called an NC program for the wire processing machine.
[0011]
Conventionally, when an operator performs a desired machining on a three-dimensional solid surface model, the operator has to create a machining path on specifications that the NC program generation unit of the wire CAM device necessarily requires. The reason is that the 3D CAD model expresses the product shape itself as a solid, so it naturally has a larger amount of information than the 2D shape. This is because when a wire processing path shape is transferred to the wire CAM, it is necessary to recreate the two-dimensional processing path format that can be processed by the conventional wire CAM.
[0012]
However, when creating a path for machining a target shape that can be placed on the program specifications for machining the shape, the operator needs to draw a machining path using 3D CAD based on the product shape. There was a problem with the difficulty of drawing. The operation of creating a wire path from a three-dimensional model by three-dimensional CAD, which has been conventionally required, is as shown in FIG. First, the operator searches for a wire-processable portion of the three-dimensional model, and extends all the surfaces to be processed to a place where the surface of the same wire processing specification is placed. Next, a cross-sectional line of the model corrected with the height of the upper and lower program specifications is created to create a two-dimensional contour shape. Furthermore, depending on the shape, it may be necessary to correlate the paths of the upper and lower program specifications in order to process the target shape.
[0013]
In addition, when trying to wire a curve that does not ride on the upper and lower program specifications, the shape that is processed with the wire cannot be determined uniquely for two unsupported curves. The same method as the solid surface is used. For such work, the present invention creates an NC program as follows.
[0014]
Embodiment 1 FIG.
Hereinafter, the work procedure according to the present invention will be described with reference to FIGS. The CAD / CAM device for carrying out the present invention is constituted by a computer system, but the illustration of the configuration is omitted. An NC program for wire processing is created in steps S1 to S4 from the three-dimensional model (instructed three-dimensional CAD solid surface product model). In step S1 (processing target specifying step 104), the operator specifies a three-dimensional model to be processed with the mouse. Next, in step S2 (machining shape extraction step 105), machining shape extraction is performed, and a wire machining path of the upper and lower program specifications of the wire machining portion of the three-dimensional model is created. When automatic machining designation is executed in step S3 (automatic machining designation step 106), machining is automatically designated for the wire machining path extracted by shape extraction. In step S4 (NC program generation step 107), the NC program for wire processing is created from the wire processing path using the NC program generation of the conventional wire CAM device, and the NC program is confirmed by superimposing it on the three-dimensional model.
[0015]
The wire shape extraction is an apparatus that automatically extracts a wire processing path for passing to a wire CAM of the upper and lower program specifications of a recognized part by automatically recognizing a wire processable part of a three-dimensional model. FIG. 4 is a flowchart of wire shape extraction. The shape designation in step S5 is a step in which the operator designates a shape to be processed from the three-dimensional model. The wire surface determination in step S6 is a step of determining a surface that can be wire-processed as one surface from the specified three-dimensional shape. The path interference determination in step S7 is a step of determining a surface that does not interfere with the path in order to check whether or not the product shape is cut by processing using a surface capable of wire processing. In the processing shape extraction in step S8, wire processing is a step of creating a processing path of program specifications for processing the surface determined to be wire processing in steps S6 and S7. In the continuation of the machining shape in step S9, the extracted paths are made continuous and combined into one machining unit of the wire. In the shape type setting in step S10, the type of machining shape and the machining order are determined from the information recognized in steps S6 to S9. The creation information of each step is recorded in DB (database) 1 to DB5, respectively. The determination of the surface capable of wire processing is performed in the internal processing of step S6, and it is determined whether or not the wire processing is possible by processing whether or not the three-dimensional curved surface satisfies the conditions for wire processing.
[0016]
FIG. 5 is a flowchart for determining a surface where wire processing is possible. Extracting a surface from DB1 in step S11 is a step of extracting one surface from DB1 that records the three-dimensional curved surface designated by the operator. In the determination of the surface that can be wire-processed in step S12, it is a step of determining whether or not one of the extracted surfaces can be wire-processed. Surface that can be processed in step S13? Then, if processing is possible, the process branches to step S14, and if wire processing is not possible, the process branches to step S15. In recording the surface in DB2 in step S14, this is a step of recording the determined surface in DB2, which records a surface that can be wire-processed as one surface. Have all the faces in step S15 been judged? Then, if there are still faces to be judged in DB1, the process branches to Step 1, and if all faces are judged, the process branches to the end.
[0017]
In order to determine whether or not one surface can be wire-processed in the internal processing in step S12, the determination of whether or not one surface can be wire-processed is made based on the shape type. FIG. 6 is a flowchart for determining whether wire processing is possible on one surface. In the branch of step S16, if the type of the three-dimensional curved surface is a plane, a cylindrical surface or a spline surface, the process branches to step S17. Otherwise, the process branches to the end without being able to determine whether wire processing is possible. In step S17, the flow branches to step S18 if the surface type is flat, step S19 if it is a cylindrical surface, and step S20 if it is a spline surface. In the plane determination in step S18, it is determined whether or not the plane can be wire-processed. In the cylindrical surface determination in step S19, it is determined whether or not the cylindrical surface can be wire-processed. In the spline surface determination in step S20, it is determined whether or not the spline surface can be wire-processed. For each three-dimensional shape type wire processing possible judgment, in order to judge whether one surface can be wire-processed by the internal processing of steps S18 to S20, the edge judgment, the half primary judgment and the angle judgment are considered in consideration of the edge. To do.
[0018]
7 to 9 are flowcharts of plane determination, cylindrical surface determination, and spline surface determination, respectively. The determination of the plane and the determination of the cylindrical surface are the same as the processing procedure, but are different because the internal processing is different due to the difference in the geometric information of the three-dimensional shape. The determination of the spline surface is a process performed by adding a one-sided primary determination for determining whether or not the surface can represent the shape as a wire processing path. Since the contents of the determination process are all similar except that all the internal processes are different, a flowchart of determination of the spline surface will be described. In the edge determination in step S21, a processing start / end ridge line is searched from the boundary of the surface on which the wire processing is determined to be possible, and it is determined whether the ridge line can be processed by the wire. In the parameter range calculation in step S22, the upper parameter range and lower parameter range of the start / end edge of the surface are calculated. In the isoline creation in step S23, a constituent curve in the wire feed direction is created uniformly in the vertical direction within the parameter range calculated from the start and end ridgelines in step S22. In the one-sided primary judgment in step S24, it is judged that the constituent curve in the wire feed direction created in step S23 is a straight line (primary). In the determination of the inclination angle in step S25, it is determined that the taper angle is such that all the constituent curves in the wire feed direction created in step S23 are within the limits of the processing machine. In the branch of step S26, if all the judgments are OK, the process branches to step S27, and if one of the judgments is NG, the process branches to the end. The processable surface flag setting in step S27 is a step of attaching a processable flag to a surface that is determined to be wire-processable as one surface.
[0019]
Edge judgment
In the edge determination, when the wire processing is performed on the three-dimensional curved surface by the internal processing in step S21 (FIG. 9), the start and end edges of the surface that becomes the start / end position of the wire path of one surface can be searched, and the wire can be fed at that edge. Judge that. FIG. 10 is a conceptual diagram of edge determination for a surface. The calculation of each edge 108 is slightly different between the plane, the cylindrical surface, and the spline surface, but the processing is almost the same. Therefore, the contents of the plane edge determination processing will be described here. FIG. 11 is a flowchart of plane edge determination. Obtaining the center of the surface in step S28 is a step of obtaining the approximate center position of the surface by obtaining the center of the boundary of the surface. In step S29, the maximum distance point is obtained by searching for the point A at the position where the distance is maximum from the boundary of the surface. In step S30, an edge having a specified angle or less is obtained, in which the edge having a steeper angle than the two edges connected to the point A is obtained. The step of obtaining the maximum point from the edge of the maximum distance in step S31 is a step of obtaining the maximum point from the edge of the maximum distance. In step S32, obtaining an edge with a specified angle or less is a step of obtaining an edge having a steeper angle than the two edges connected to the point A. In the branch of step S33, if the edge is a straight line (primary), the process branches to step S34, and if the edge is not a straight line, the process branches to the end. In the branch of step S34, if there is no point outside the start / end edge, the process branches to step S35, and if present, the process branches to the end. The setting of the start / end edge and the up / down parameter in step S35 is a step of recording the upper / lower edge parameter for the start / end edge. The setting of the geometric direction in step S36 is a step of determining and recording which one of the geometric directions is the direction of movement of the wire machining path from the start and end parameters.
[0020]
Isoline creation considering edges
Isoline creation in consideration of edges is performed by obtaining points on the curved surface in the wire feed direction evenly in the direction of movement of the wire processing path from the parameter range of the upper and lower parameters obtained by edge judgment in the internal processing of step S23 (FIG. 9). Recording process. FIG. 12 is a conceptual diagram of an isoline considering an edge. FIG. 13 is a flowchart of isoline creation in consideration of edges. Step S37 is a step for obtaining parameter ranges above and below the start and end edges. Step S38 is a step of substituting 0.0 for the parameter A in the wire processing path direction. Step S39 is a step of substituting 0.1 for the parameter increment value ΔA. Step S40 is a step for obtaining a surface geometry variable value from the ratio when the start position is 0.0 and the end position is 1.0. Step S41 is a step for obtaining the upper and lower coordinates of the surface from the surface geometry variable value. Step S42 is a step for obtaining the coordinates of a point on the surface between the upper and lower coordinate parameters. The branch of step S43 is a step that branches to step S40 when the parameter A + ΔA is 1.0 or less, and the branch to the end after that.
[0021]
Primary judgment
In the primary judgment, the surface moves up and down by judging that the point sequence in the wire feed direction of the three-dimensional curved surface created by isoline creation in the internal processing of step S24 (FIG. 9) can be regarded as a substantially straight line (primary). This is a process for determining that the surface can be processed by the machining path twin. FIG. 14 is a conceptual diagram of one-sided primary determination. FIG. 15 is a flowchart of one-sided primary determination. Step S44 is a step of obtaining the wire feed direction of the surface to be judged. Step S45 is a step of taking out a point sequence in the wire feed direction. Step S46 is a step of creating a straight line connecting the first and last points of the point sequence. Step S47 is a step of obtaining the maximum amount Tol of the distance between the straight line and the point sequence in the wire feed direction. The branch of step S48 is a step of branching to step S49 if Tol is 0.001 or less, and branching to the end if larger than that. The branch of step S49 is a step of branching to step S50 if all the isolines 110 are checked, and branching to step S45 if not. Step S50 is a step of setting a flag in which the primary judgment is OK.
[0022]
Angle judgment
The angle determination is a process of determining that the straight line angle created by isoline creation in the internal process of step S25 (FIG. 9) is equal to or less than a specified angle. FIG. 16 is a conceptual diagram of angle determination. FIG. 17 is a flowchart of angle determination. Step S51 is a step of obtaining the wire feed direction 111 of the surface to be determined. Step S52 is a step of taking out a point sequence in the wire feed direction. Step S53 is a step of creating a straight line connecting the first and last points of the point sequence. Step S54 is a step of obtaining an angle θ between the straight line and the program specification height direction. The branch of step S55 is a step of branching to step S56 if θ is equal to or less than the specified angle, and branching to the end if larger than that. The branch of step S56 is a step of branching to step S57 if all isolines are checked, and branching to step S52 if not. Step S57 is a step of setting a flag whose angle determination is OK.
[0023]
Path interference judgment
The path interference determination is a process for determining whether or not to cut into the product shape on the wire processing path of the surface in the internal processing of step S7 (FIG. 4). The interference case includes a case as shown in FIG. The case 1 (see circles 1 to 3 in FIG. 19) is a case where the path interferes and is completely cut into a shape. The case 2 is a case where there is no path interference. The case 3 is a case where the path is partially interfered. 19A and 19B are conceptual diagrams of processing for determining path interference on a surface. It can be said that the path does not interfere unless one of the front and back surfaces interferes. Further, when there is no path interference, it can be determined that the interference side is the product shape. If both the reverse does not interfere either to become an incomplete product shape with no contents, it is determined that you do not know what made the product shape. FIG. 20 is a flowchart for determining route interference. Step S58 is a step of extracting a surface from DB2 (see FIG. 4) that records a surface that is determined to be wire-processable as one surface. Step S59 is a step of determining interference on a path for processing one surface. The branch of step S60 is a step of branching to step S64 when completely interfering, branching to step S61 when not interfering, and branching to step S62 when partially interfering. Step S61 is a step of setting a no-route-interference flag. Step S62 is a step of setting an interference flag in the portion. Step S63 is a step of recording the surface together with the interference information in the DB 3 for recording the shape that does not completely interfere with the path. The branching of step S64 is a step of branching to step 58 if there are still faces to be judged in DB2, and branching to the end if all faces are judged.
[0024]
The determination of one-way path interference is processing for determining path interference for one surface in the internal processing of step S59 (FIG. 20). FIG. 21 is a flowchart for determining the path interference of one surface. Step S65 is a step of creating an n-point wire processing path passing through the surface. Step S66 is a step of creating a light beam in the wire feed direction at one position from the point created in the previous process on the inside and outside of the surface. Step S67 is a step of checking the interference between the entire three-dimensional model and the inner light ray. Step S68 is a step of checking the interference between the entire three-dimensional model and the outside light beam. The branch of step S69 is a step that branches to step S70 if both sides interfere, and branches to step S71 if either does not interfere. Step S70 is a step of incrementing the count of the number of interferences on the surface by one. The branch of step S71 is a step that branches to step S72 if all points are checked, and branches to step S66 if not. Step S72 is a step of calculating the interference rate from the number of interferences / n.
[0025]
Ray interference judgment
FIG. 22 is a flowchart of ray interference determination, FIG. 23 is a conceptual diagram of BOX convergence, and FIG. 24 is a conceptual diagram of triangular patch search. The ray interference check determines that the line interferes with the shape. As shown in FIG. 22, the intersection surface in the three-dimensional model is narrowed down by range convergence, and the triangular patch and line of the surface as shown in FIGS. If the intersection is within the triangular patch, it is determined that interference occurs. This is basically the same processing as that used for the mouse instruction on the surface of the three-dimensional CAD.
[0026]
Machining shape extraction
Machining shape extraction is a process of creating a wire machining path on the Z specifications for machining the surface that is determined to be wire machineable by the above judgment in the internal process of step S8 (FIG. 4). By this processing, machining path information that can be NC-generated by the conventional wire CAM is created. FIG. 25 is a flowchart of processing shape extraction. Step S73 is a step of taking out from the DB 3 for recording the surface determined as the surface capable of wire processing by the surface determination and the interference determination. The branch of step S74 is a step of branching to step S75 if the interference type is no interference and branching to step S76 if the interference type is partial interference. Step S75 is a step of creating an upper and lower wire machining path for the entire surface. Step S76 is a step of creating an upper and lower wire machining path only in a portion where the surface does not interfere. Step S77 is a step of recording the surface and its wire processing path in DB4. The branch of step S78 is a step that branches to the end when processing of all the surfaces of DB3 is completed, and branches to step S73 otherwise.
[0027]
Machining path extraction
The machining path extraction is a process of creating an entire upper and lower wire machining path for one surface in the internal process of step S75 (FIG. 25). FIG. 26 is a flowchart of processing shape extraction of one surface. Step S79 is a step for setting the parameter A to 0.0. Step S80 is a step in which the parameter increment value ΔA is obtained by convergence calculation so that the specified machining tolerance is obtained. Step S81 is a step of creating an isoline in the wire feed direction of the designated parameter. Step S82 is a step for obtaining a point obtained by extending the straight line at the start point and end point of the isoline to the specified vertical Z specifications. In step S83, the upper and lower points obtained in step S81 are additionally recorded in the surface information. The branching of step S84 is a step of branching to step S80 when the parameter A is smaller than 1, and branching to step S85 when the parameter A is more than that. In step S85, the upper and lower points when the parameter A is 1.0 are additionally recorded in the surface information.
[0028]
Extraction of partial interference path
The partial interference path extraction is a process of creating upper and lower wire processing paths when a part of one surface interferes with one surface in the internal processing of step S76 (FIG. 25). In the partial interference judgment, as shown in FIG. 27, a detailed interference check is performed on a saw and a surface processing range is obtained so that a path can be created from a surface having the interference shape 113. FIG. 28 is a flowchart for extracting a partial interference path of one surface. Step S86 is a step of creating a machining path for the entire surface. Step S87 is a step in which a detailed interference check is performed to obtain the upper and lower parameter ranges of the non-interfering part. Step S88 is a step of creating a list of upper and lower parameter ranges of a plurality of extracted portions obtained by the detailed interference check. Step S89 is a step for extracting one upper and lower parameter range of the extracted portion from the list. Step S90 is a step of creating a path for processing the surface of the extracted vertical parameter range. In the branch of step S91, if the parameter range remains from the list, the process branches to step S89, and if not, the process branches to the end.
[0029]
Detailed interference check
The detailed interference check is a process for obtaining a processing range of the surface by performing a detailed interference check on the saw and recognizing the interference shape in the internal processing in step S87 (FIG. 28). FIG. 29 is a flowchart of the detailed interference check. Step S92 is a step for checking interference with a parameter A in a sawtooth shape. The branch of step S93 is a step that branches to step S94 if the current state is an interference state, and branches to step S95 if the current state is a non-interference state. The branch of step S94 is a step of branching to step S96 if there is no interference, and branching to step S98 if there is interference. The branch of step S95 is a step of branching to step S97 if there is interference, and branching to step S98 if there is interference. Step S96 is a step of extracting a plurality of shapes that interfered immediately before the end of interference. Step S97 is a step of extracting a plurality of shapes that have interfered. The branching of step S98 is a step of branching to step S99 if there is an interference shape capable of wire processing, and branching to step S102 if not. Step S99 is a step of obtaining an intersection line between the interference shape and the surface for creating the wire path. Step S100 is a step of obtaining parameters above and below the intersection obtained in step S99. Step S101 is a step of recording the parameter range obtained in step S100 together with the interference shape. The branch of step S102 is a step of branching to step S92 if there is a part that has not been checked yet in terms of extracting the wire path, and branching to the end when all the checks are completed.
[0030]
Continuous machining shape
Continuation of the machining shape is a process of grouping the paths into wire machining units by continuating the wire machining paths created in step S8 in the internal process of step S9 (FIG. 4). At the same time, the type of wire processing is determined from the result of continuation and the result of recognizing the three-dimensional model. FIG. 33 is a flowchart of continuous machining shapes. Step S103 is a step of creating a machining path shape from a machining pass of one surface unit by continuating one wire machining unit. Step S104 is a step of recording the machining shape type information in a continuous machining path shape. Step S105 is a step of recording the machining path shape in the shape DB of the wire CAM. The branch of step S106 is a step of branching to step S103 if there is a shape that is not yet continuous, and branching to the end if there is no shape.
[0031]
The machining shape continuation sub is a process of creating a machining path shape from a machining pass of one surface unit by continuating one wire machining unit in the internal processing of step S103 (FIG. 30). FIG. 31 is a flowchart of continuation of one wire processing unit. Step S107 is a step of obtaining a path of the surface to be processed that has not been made continuous from DB4 (see FIG. 4) that records the wire processing path. Step S108 is a step of searching for a surface connected to the surface within a specified error range. Step S109 is a step of performing error correction of both paths when there is a connection error. Step S110 is a step in which the surface found this time is set as the surface to be searched for next connection. Step S111 is a step of setting a continuous flag for the surface discovered this time. The branch of step S112 is a step that branches to step S113 when there is no surface to be connected or is connected to the surface where the search is started, and the other branch to step S108. Step S113 is a step of collectively registering paths that are continuous in one processing unit.
[0032]
Processing type information judgment
In the recording of the processing type information, the processing type of the wire is determined based on the result of continuation and the result of recognizing the three-dimensional model in the internal processing in step S104 (FIG. 30). FIG. 32 is a flowchart of processing type information recording. In step S114, the shape type such as punch and die determined from the result of continuation and the result of recognizing the three-dimensional model is determined and set. Step S115 is a step for determining and setting a straight / upper / lower arbitrary processing type determined from the result of continuation. Step S116 is a step of determining a shape type and setting an appropriate processing order for a plurality of processing shapes.
[0033]
The shape type setting is a process of setting information by determining the shape type of the die, punch, open, and hole in the internal processing in step S114 (FIG. 32). FIG. 33 is a flowchart for setting the shape type. The branch of step S117 is a step of branching to step S118 if the result of continuation is other than the open shape, and branching to step S123 if the shape is open. The branch of step S118 is a step of branching to step S119 if the product shape is outside the contour from the result of the interference check, and branching to step S122 if the product shape is inside. The branch of step S119 is a step of branching to step S120 if it is not a hole from the result of shape recognition, and branching to step S121 if it is a hole. Step S120 is a step of setting a die shape type flag. Step S121 is a step of setting a hole shape type flag. Step S122 is a step of setting a punch shape type flag. Step S123 is a step of setting an open shape type flag. Step S124 is a step of setting the shape type flag to the machining shape.
[0034]
The machining type setting is a process of setting information by judging whether the machining shape is straight and an arbitrary machining type up and down in the internal processing of step S115 (FIG. 32). FIG. 34 is a flowchart of processing type setting. Step S125 is a step in which it is checked whether there is a portion where the top and bottom are different in the machining shape path of one machining unit. The branch of step S126 is a step of branching to step S127 when there is a portion where the upper and lower paths are different from the result of step S125, and branching to step S128 if there is no part. Step S127 is a step of setting a flag of any shape type up and down. Step S128 is a step of setting a straight shape type flag. Step S129 is a step of setting a machining type flag to a machining shape.
[0035]
The processing order setting is processing for setting a proper processing order for the path in the internal processing in step 116 (FIG. 32). FIG. 35 is a flowchart of processing order setting. In step S130, hole-shaped machining shapes are searched and numbered in order from the closest. In step S131, die-shaped machining shapes are searched and numbered in order from the closest. In step S132, the punched machining shapes are searched and numbered in order from the closest. In step S133, the machining shapes having the open shape are searched and numbered in ascending order.
[0036]
Automatic processing designation
The automatic machining designation is a process for automatically determining an appropriate machining start (IH) position and approach position for a wire machining path extracted from a three-dimensional model. Recognition of a three-dimensional model is used to determine the processing order, IH position, and approach position. FIG. 36 is a flowchart of automatic machining designation. Step S134 is a step of taking out the wire processing shapes in the processing order set in the processing order setting in step 116 of wire shape extraction. The branching of step S135 is a step of branching to step S136 if the machining type of step 115 is straight, and branching to step S137 if arbitrary up and down. Step S136 is a step of determining the straight approach position of the wire processing path. Step S137 is a step of determining an arbitrary vertical approach position above and below the wire processing path. The branch of step S138 is a step of branching to step S139 when the shape type of step 114 is a die, branching to step S140 if punching / opening, and branching to step S141 if punching / opening. Step S139 is a step of determining the IH position of the die. Based on the interference judgment, the center position inside the path perpendicular to the approach shape is obtained and set to the position where the designated approach length is obtained. Step S140 is a step of determining an IH position for punch opening. The position outside the path perpendicular to the approach shape is determined by interference judgment, and the position is set to the designated approach length. Step S141 is a step of determining the IH position of the hole. Set the center of the hole to the start position. The branch of step S142 is a step in which it is determined whether there is an interfering shape while approaching from IH. If there is no interference, the process branches to step 143, and if it interferes, the process branches to step 135. Step S143 is a step of defining the wire processing based on the determined IH position approach position. The branch of step S144 is a step that branches to step 134 if there is a shape that has not yet been designated for machining, and branches to the end when the machining designation has been completed for all machining shapes.
[0037]
Curve path extraction
Curve processing path extraction is an apparatus that creates a wire processing path of upper and lower program specifications from a three-dimensional curve that is not necessarily parallel. FIG. 37 is a conceptual diagram of extraction of the curve processing path 117. Since the correspondence between the three-dimensional curves 115 is not uniquely obtained like a three-dimensional curved surface, the operator needs to indicate the correlation between the upper and lower curves as the corresponding position 116 of the upper and lower paths in order to create the intended shape. . Correlation between corresponding positions is determined so as to be even at the length ratio of the upper and lower curves. FIG. 38 is a flowchart of curve machining path extraction. Step S145 is a step of discriminating whether the upper and lower curved shape types are a closed shape or an open shape. The branch of step S146 is a step of branching to step S147 if both the upper and lower shape types determined in step S145 are open or closed, and branching to the end otherwise. Step S147 is a step in which the initial corresponding position is determined based on the open shape end point or the corresponding position designation.
[0038]
In step S148, the next corresponding position is obtained along the curve, and the length parameter at the element of the three-dimensional curve in the meantime is set equally to the upper and lower lengths so that the final position is 1.0. . Step S149 is a step of performing a convergence calculation on the parameter increment value ΔA so as to be equal to or less than the specified tolerance. Step S150 is a step of calculating corresponding points on the upper and lower curves from the calculation formula of each curve element from parameter A. Step S151 is a step of calculating the intersection of the line passing through the upper and lower points of step S150 and the plane of the upper and lower specification heights and additionally storing it in the path. The branch of step S152 is a step that branches to step S149 if the parameter A is smaller than 1, and branches to step S153 if it is more than that. Step S153 is a step of additionally storing the point when the parameter A = 1.0 in the path. The branching of step S154 is a step of branching to the end when the shape returns to the starting point or the final position, and branching to step 148 otherwise.
[0039]
FIG. 39 is a comparison diagram of the conventional operation flow and the operation flow incorporating the effects of the invention in the first invention of the present invention. When creating from the shape of the 3D model to the machining definition shape for generating the NC of the shape, as shown in FIG. 39 (a), all of the conventional operations are performed by the operator using 3D CAD and 2D CAD. However, by adopting the present invention, as shown in FIG. 39 (b), the operator can automatically perform all operations up to creating a machining definition shape for NC generation only by instructing the machining target. There is an effect that becomes possible.
[0040]
In the second invention of the present invention, if the second invention is not included in the first invention in the internal processing of the first invention, for example, many three-dimensional shapes such as a three-dimensional shape that looks simple but has steps as shown in FIG. Although the processing shape cannot be extracted for the shape, the processing shape can be extracted for almost any shape that can be wire processed by incorporating the second invention.
[0041]
FIG. 41 is a comparison diagram of a conventional operation flow and an operation flow incorporating the effects of the invention in the third invention of the present invention. The association that has been performed for the path in the past is performed on the three-dimensional curve, but the work of creating and drawing the surface becomes unnecessary.
[0042]
【The invention's effect】
As described above, according to the present invention, For wire processing machines that move the upper and lower guides to move the wires stretched between these guides and perform processing by electric discharge between the wires and the workpiece A method of creating machining path information for generating an NC program for machining a model from a three-dimensional model in a CAD / CAM apparatus, wherein a surface 3 is obtained from a solid surface three-dimensional model of an indicated three-dimensional CAD. Dimensional surface type Start and end ridge lines that indicate the range of machining start and end of the boundary surface 3D model wire processing is performed by determining whether or not wire processing of the surface is possible based on the taper angle of the constituent curve in the wire feed direction and whether there is path interference in which the wire processing path cuts into the 3D model. From the process of automatically recognizing the parts that can be processed by the machine and the parts that can be processed by the wire processing machine, According to the NC program command of the guide Creates a wire processing path of program specifications indicating the movement of the program command height and the arbitrary shape command height, groups it into wire processing units, automatically recognizes the wire processing machine operation from the 3D model, and generates the processing path Machining path information in a CAD / CAM device comprising: a step of creating, and a step of setting a machining type based on information referred to by a three-dimensional model and setting a machining type of an appropriate wire Therefore, it is possible to automate the recognition of the machining portion, the creation of the path, and the machining definition that the operator has been working in the past.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram of wire processing.
FIG. 2 is a diagram for explaining an operation for wire processing a three-dimensional model.
FIG. 3 is a diagram showing a work procedure according to the present invention.
FIG. 4 is a flowchart of an operation at the time of wire shape extraction in the present invention.
FIG. 5 is a flowchart of an operation when determining a wire-workable surface in the present invention.
FIG. 6 is a flowchart of an operation when classifying judgments according to surface types in the present invention.
FIG. 7 is a flowchart of an operation in determining a plane according to the present invention.
FIG. 8 is a flowchart of an operation when judging a cylindrical surface according to the present invention.
FIG. 9 is a flowchart of an operation in determining a spline surface according to the present invention.
FIG. 10 is a conceptual diagram of edge determination in the present invention.
FIG. 11 is a flowchart of an operation in edge determination according to the present invention.
12 is a conceptual diagram of isorun creation in consideration of edges in the present invention. FIG.
FIG. 13 is a flowchart of an operation when creating an isorun in consideration of edges in the present invention.
FIG. 14 is a conceptual diagram of one-sided primary determination in the present invention.
FIG. 15 is a flowchart of the operation at the time of one-sided primary determination in the present invention.
FIG. 16 is a conceptual diagram of angle determination in the present invention.
FIG. 17 is a flowchart of the operation at the time of angle determination in the present invention.
FIG. 18 is a conceptual diagram of route interference determination processing in the present invention.
FIG. 19 is a diagram showing a determination example of path interference determination in the present invention.
FIG. 20 is a flowchart of the operation in determining route interference according to the present invention.
FIG. 21 is a flowchart of the operation in determining the path interference of one surface in the present invention.
FIG. 22 is a flowchart of the operation in determining the light beam interference according to the present invention.
FIG. 23 is a conceptual diagram of BOX convergence in the present invention.
FIG. 24 is a conceptual diagram of a triangular patch search according to the present invention.
FIG. 25 is a flowchart of an operation when extracting a machining shape according to the present invention.
FIG. 26 is a flowchart of an operation in extracting a machining path for one surface in the present invention.
FIG. 27 is a conceptual diagram of processing path extraction of a partially interfering surface in the present invention.
FIG. 28 is a flowchart of an operation when extracting a machining path for a partially interfering surface according to the present invention.
FIG. 29 is a flowchart of the operation when performing a detailed interference check for partial interference in the present invention.
FIG. 30 is a flowchart of an operation when making a machining shape continuous in the present invention.
FIG. 31 is a flowchart of the operation when the one-wire machining shape is made continuous in the present invention.
FIG. 32 is a flowchart of the operation when determining processing type information in the present invention.
FIG. 33 is a flowchart of the operation at the time of shape type determination in the present invention.
FIG. 34 is a flowchart of the operation at the time of processing type determination in the present invention.
FIG. 35 is a flowchart of the operation in determining the processing order according to the present invention.
FIG. 36 is a flowchart of the operation at the time of designating automatic processing in the present invention.
FIG. 37 is a conceptual diagram of extraction of a curved machining path in the present invention.
FIG. 38 is a flowchart of an operation in extracting a curved machining path according to the present invention.
FIG. 39 is a diagram for explaining one effect in the present invention.
FIG. 40 is a diagram showing a three-dimensional shape with a step.
FIG. 41 is a diagram for explaining another effect in the present invention.
[Explanation of symbols]
100 wire machining path, 101 wire, 102 upper guide, 103 lower guide, 104 machining target designation, 105 machining shape extraction, 106 automatic machining designation, 107 NC program generation, 108 edge, 109 upper and lower points, 110 isoline, 111 wire Feed direction, 112 rays, 113 interference shape, 115 three-dimensional curve, 116 corresponding position designation, 117 wire processing path.

Claims (6)

A model is processed from a three-dimensional model in a CAD / CAM device for a wire processing machine that moves a wire stretched between these guides by moving the upper and lower guides and performs processing by electric discharge between the wire and the workpiece. A method of creating machining path information for generating an NC program to be performed,
From the specified 3D CAD solid surface 3D model, the composition curve in the wire feed direction according to the start and end edges of the 3D curved surface type and the boundary surface of the surface, indicating the start and end of processing Determines whether surface wire processing is possible based on the taper angle of the wire and the presence or absence of path interference where the wire processing path cuts into the 3D model, and automatically recognizes parts that can be processed by the 3D model wire processing machine And the process of
Create wire processing paths of program specifications that show the movement of the command command height and the arbitrary shape command height of the guide from the part that can be processed by the wire processing machine, and group them into wire processing units. A process of automatically recognizing wire processing machine operation from a three-dimensional model to create a processing path;
A process type setting based on information referred to from the three-dimensional model, and a process of setting an appropriate wire machining type;
A method for creating machining path information in a CAD / CAM device, comprising: In the process of creating a machining path by automatically recognizing, when creating a machining path for machining a machineable part, it is possible to avoid obstacles in the middle of the path by judging the interference between the path and the obstacle in the middle. The method of creating machining path information in the CAD / CAM apparatus according to claim 1, wherein the machining path information is created.   When creating a wire processing path, in the case of a pair of three-dimensional curves created by three-dimensional CAD, an intended wire is designated by designating corresponding positions of these shapes indicating the correlation between the pair of three-dimensional curves from the outside. The machining path information creating method in the CAD / CAM apparatus according to claim 1, wherein a machining path is created. A model is processed from a three-dimensional model in a CAD / CAM device for a wire processing machine that moves a wire stretched between these guides by moving the upper and lower guides and performs processing by electric discharge between the wire and the workpiece. When creating machining path information for generating NC programs
From the specified 3D CAD solid surface 3D model , the composition curve in the wire feed direction according to the start and end edges of the 3D curved surface type and the boundary surface of the surface, indicating the start and end of processing Determines whether surface wire processing is possible based on the taper angle of the wire and the presence or absence of path interference where the wire processing path cuts into the 3D model, and automatically recognizes parts that can be processed by the 3D model wire processing machine Means to
Create wire processing paths of program specifications that show the movement of the command command height and the arbitrary shape command height of the guide from the part that can be processed by the wire processing machine, and group them into wire processing units. Means for automatically recognizing wire processing machine operation from a three-dimensional model to create a processing path;
A means for setting a processing type based on information referred to from the three-dimensional model, and setting an appropriate wire processing type;
A CAD / CAM device characterized by comprising: When creating a machining path for machining a machineable part by automatically recognizing and creating a machining path , obstacles in the middle of the path can be avoided by judging interference between the path and the obstacle in the middle. CAD / CAM apparatus of claim 4, wherein the creating Te.   When creating a wire processing path, in the case of a pair of three-dimensional curves created by three-dimensional CAD, an intended wire is designated by designating corresponding positions of these shapes indicating the correlation between the pair of three-dimensional curves from the outside. The CAD / CAM device according to claim 4, wherein a machining path is created.

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