JP2007058531A - Use order determination method and use order determination program for tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a use order determination method of a machining tool, capable of easily and rapidly determining use order of the machining tool capable of reducing a machining time. <P>SOLUTION: In this use order determination method, each section model when slicing a work model and a product model in a height direction at prescribed intervals is generated, a machining section part obtained by removing a product section shape from a work section shape is generated, a machining time capable of shaving a portion by a tool of a maximum diameter, of the machining section part in each of a plurality of tool order patterns wherein the tools stored in a database are arranged in a descending order of a diameter, generates a section part remaining, and repeats calculation of a machining time of a portion capable of shaving a section part remaining by the tool of a diameter sequentially reduced in order according to the tool order pattern until no section part remaining exists, and generation of a section part further remaining, and extracts the tool order pattern having the shortest total machining time obtained by adding up the calculated machining times. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for determining the order of use of machining tools, and more particularly to a method for determining the order of use of a tool for determining the order of use of a plurality of rotating processing tools for machining a workpiece into a product shape.

  In general, when a material is cut by an NC machine tool using a processing tool such as an end mill and finished into a product shape, tools of various sizes and types are used. Conventionally, when cutting a material with such a plurality of tools, the use order of the tools to be used has been set by the operator based on experience and intuition each time according to the product shape.

  On the other hand, Patent Document 1 discloses a method of performing a machining simulation for each tool and determining a combination of tools with the shortest machining time from the simulation result.

JP 09-050311 A

  Here, in recent years, especially in the automobile industry, the development period of vehicles tends to be shortened. Accordingly, in the manufacturing process, not only the machining time of individual parts is shortened, but also the creation period of NC data including tool settings and the like. It is also required to shorten the manufacturing preparation period such as the production time of the die cast mold.

  However, in the tool setting based on the above-mentioned operator's experience and the like, there is a limit to shortening the machining time and the preparation period, and there are variations among operators. In other words, there is no clear criterion for tool setting, and it takes a lot of time for machining, and the tool setting may be repeated many times. In particular, for example, when a die-cast die composed of a plurality of split dies (cores) is formed by cutting, a total of several hundred hours are required to produce all the split dies, including the creation of NC data. Sometimes it took.

  On the other hand, in the method of Patent Document 1, it takes a lot of time to simulate a product having a three-dimensional shape, and further, it is necessary to perform machining simulation for all the tools, so that the final result of the combination of tools is obtained. It takes a lot of time to complete and is not practical.

  Therefore, the present invention has been made to solve the above-described problems of the prior art, and a machining tool that can easily and quickly determine the order of use of machining tools that can reduce machining time. The purpose is to provide a method for determining the order of use.

In order to achieve the above object, the present invention provides a tool usage order determination method for determining the usage order of a plurality of rotating processing tools for processing a workpiece into a product shape, and a workpiece model showing a three-dimensional shape of a workpiece Storing a plurality of tool order patterns in which a product model showing a three-dimensional shape of a product and a processing tool in a predetermined pattern in order from a large diameter to a small diameter are stored in a database, and workpieces stored in the database From the model and product model, a plurality of two-dimensional workpiece cross-section models and a plurality of two-dimensional workpiece cross-section models showing the workpiece cross-sectional shape and the product cross-sectional shape when the workpiece model and product model are sliced at a plurality of surfaces at predetermined intervals in the height direction The two-dimensional workpiece cross-sectional model and the two-dimensional product cross-sectional model are mutually exchanged in each of the plurality of slice planes For each tool sequence pattern stored in the database, a tool with the maximum diameter of the tool sequence pattern is used to generate a machined cross-section that excludes the product profile from the workpiece profile. With a tool that calculates the machining time of the part that can be scraped off, generates a cross-sectional portion that remains uncut, and further reduces the diameter in order according to the tool sequence pattern until there is no cross-sectional portion that remains uncut. The process of repeatedly calculating the machining time of the portion that can be cut out of the remaining cross-sectional portion and the generation of the remaining cross-sectional portion are combined with the machining time calculated by each tool in this step. And a step of calculating a total machining time and extracting a tool sequence pattern having the shortest total machining time.
In the present invention configured as described above, the tool sequence pattern having the shortest total machining time is extracted using the cross-sectional models of the workpiece model and the product model, so that a two-dimensional calculation process is sufficient. As a result, the calculation time can be greatly shortened. Furthermore, a plurality of tool order patterns in which machining tools are arranged in a predetermined pattern in order from the largest diameter to the smallest diameter are stored in the database, and the tool order pattern with the shortest total machining time is selected from the stored tool order patterns. Since the extraction is performed, the tool usage order can be determined efficiently, and the machining time can be shortened according to the tool usage order. Furthermore, since the calculation of the machining time of the portion that can be scraped out of the remaining cross-sectional portion is repeated until there is no remaining cross-sectional portion, the machining time can be accurately calculated.

In the present invention, preferably, the remaining cross-sectional portion is generated as a portion through which the tool model between the tool model and the product cross-sectional shape when the tool model of the tool is moved along the product cross-sectional shape does not pass. The
In the present invention configured as described above, the cross-sectional portion that remains uncut is generated as a portion through which the tool model does not pass when the tool model is moved along the product cross-sectional shape. It can be generated with high accuracy.

In the present invention, preferably, the predetermined interval is the same as the machining depth of the tool having the smallest diameter in the tool order pattern.
In the present invention configured as above, each cross-section model is generated by slicing the workpiece model and the product model at the same interval as the machining depth of the tool with the smallest diameter in the tool order pattern, so that the machining time is more reliably ensured. It is possible to calculate with high accuracy.

  In order to achieve the above object, a tool use order determination program according to the present invention includes a workpiece model indicating a three-dimensional shape of a workpiece, a product model indicating a three-dimensional shape of a product, and a machining tool from a large diameter to a small diameter. A computer for determining a tool usage order for determining a usage order of a plurality of rotating machining tools for machining a workpiece into a product shape using a database storing a plurality of tool order patterns arranged in a predetermined pattern in the order of A tool use order determination program according to claim 1, wherein a workpiece cross-sectional shape obtained by slicing a workpiece model and a product model into a plurality of surfaces at a predetermined interval in a height direction from a workpiece model and a product model stored in a database. A plurality of two-dimensional workpiece cross-section models indicating a product cross-sectional shape and a plurality of two-dimensional product cross-section models are generated, and a plurality of slice planes are generated. In each case, a 2D workpiece cross-section model and a 2D product cross-section model are superimposed on each other to generate a machining cross-section portion that excludes the product cross-section shape from the work cross-section shape, and the machining cross-section for each tool order pattern stored in the database. Of the part, the machining time of the part that can be scraped off with the tool of the maximum diameter of the tool order pattern is generated and a cross-sectional part that remains uncut is generated, and further, until this cross-sectional part that remains uncut exists, A tool with a reduced diameter in the order according to the tool order pattern is used to calculate the machining time of the portion that can be cut out of the remaining cross-sectional portion and to further generate the cross-sectional portion that remains to be cut. The total machining time for each tool sequence pattern is calculated by adding the machining times, and the tool sequence pattern with the shortest total machining time is calculated. So as to extract the down, controls the computer tool used order determination.

  ADVANTAGE OF THE INVENTION According to this invention, the usage order of the processing tool which can shorten processing time can be determined simply and rapidly.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
First, the NC data generation system (machining condition determination system) used for setting the working tool use order according to the present embodiment will be described. FIG. 1 is a schematic configuration diagram of an NC data generation system having a machining tool use order setting function according to the present embodiment.
As shown in FIG. 1, an NC data generation system 2 is connected to an NC machine tool (numerically controlled machine tool) 1, and this NC data generation system 2 includes a CPU, a memory, a display, a keyboard, and the like (not shown). Including a computer 4 and a database 6. The computer 4 reads an NC data generation program including a tool use order setting program, which will be described later, stored in the database 6 and stores it in the memory. The NC machine tool 1 is input with NC data (numerical control data) relating to a tool, a machining locus, and the like created by the computer 4, and the NC machine tool 1 operates based on the NC data.

Next, data stored in the database 6 will be described with reference to FIGS. FIG. 2 is a perspective view (a) showing a three-dimensional shape workpiece model according to the present embodiment, a perspective view (b) showing a three-dimensional shape product model, and a plan view (c) thereof. FIG. FIG. 4 is a diagram showing a part of tool information stored in a database according to the embodiment, and FIG. 4 is a diagram showing general machining data (a) and high-precision machining data (b) of a tool pattern according to the present embodiment. is there.
The database 6 defines three-dimensional CAD data relating to products such as automobile parts and molding dies, three-dimensional CAD data relating to workpieces (materials) before the products are cut, or three-dimensional shapes of products and workpieces. A three-dimensional workpiece shape model and a three-dimensional product shape model defined by coordinate data and the like are stored. For example, as shown in FIG. 2, the workpiece 10 (FIG. 2A) has a cubic shape, which is cut out to be finished into a product shape 12 (FIG. 2B).

  Further, the database 6 stores various data relating to tools used in the NC machine tool 1 as shown in FIG. For example, in the data shown in FIG. 3, for each tool, the machining accuracy, the machining time per unit area, the maximum machining depth in one cut, and the like are defined. The tool is defined by the size of the diameter (D20 or the like), the type of ball end mill (B), flat end mill (F), or the like. Various data that influence the machining conditions such as the feed speed and cutting speed of the tool are also defined for each tool.

  Further, as shown in FIG. 4, the database 6 stores a plurality of tool patterns. This tool pattern is a pattern in which the operator predetermines the number of tools to be used and their order in a plurality of patterns (for example, several tens of patterns). Such pattern information is stored in the database 6 by the computer 4. The data shown in FIG. 4A defines a plurality of tool patterns of a tool used in general machining (processing of a general mold surface excluding a parting surface and the like). For example, in the tool pattern (1), four ball end mills are used, and the order of use is defined such that the diameters are 20 mm, 12 mm, 10 mm, and 6 mm in order of increasing tool diameter. Other tool patterns are basically defined in descending order of the tool diameter. Similarly, the data shown in FIG. 4 (b) similarly defines a plurality of tool patterns of tools used in high-precision machining (for example, machining of a parting surface when combining parting molds (cores)). It is. For example, in the tool pattern (4), a pattern is defined in which processing is performed by a flat end mill having a diameter of 10 mm and then processing is performed by a ball end mill having a diameter of 6 mm.

  Furthermore, although not shown, the database 6 stores data used for generating a machining locus (machining path) of each tool, data on tool holders, and data for NC data conversion. These data are used when setting the contour path and the path along the shape and the holder. The NC conversion data is used to generate NC data related to tools used, machining paths, holders, and the like.

  Here, an outline of a flow of NC data generation processing of the computer 4 by the NC data generation program will be described. First, based on a tool use order setting program, three-dimensional shape data relating to a product to be machined and a workpiece (material) is read out from the database 6 according to a predetermined input by an operator. An optimum tool pattern is determined according to the workpiece shape. Details of this processing will be described later. After that, based on the NC data generation program, the contour path and the path along the shape are set for each tool based on the data of the product shape and workpiece shape and the data of the tool to be used, and then the tool to be used and the determined machining path. In addition, a rigid holder that supports the tool is set. The tool and path determined by these processes are converted into NC data.

Next, mainly with reference to FIG. 5, a tool use order setting process executed by the computer 4 by the tool use order setting program according to the present embodiment will be described. FIG. 5 is a flowchart showing the processing of setting the tool use order for general machining according to the present embodiment. In FIG. 5, “S” indicates each step.
In the present embodiment, a tool pattern having the shortest machining time is automatically determined by this processing flow. In the present embodiment, the tool use order setting process according to the present invention is applied to the cutting of a die-cast mold as a product. Here, the workpiece 10 shown in FIG. 2A is cut. An example of processing to obtain a mold (split mold) 12 shown in FIG. 2B will be described. The split mold 12 shown in FIG. 2B includes a shape portion 14, a mold split portion 16, and a pedestal portion 18.

First, referring to FIG. 5, the process of setting the tool use order in general machining will be described. In this processing flow, first, in S1, the operator selects CAD data or the like stored in the database 6 to select the three-dimensional values defined by the numerical values of the three-dimensional coordinates that define the mold shape and the workpiece shape. Each shape model is read into the computer 4. In addition, the data regarding these shapes can be newly input or corrected by the operator in S1.
Next, in S <b> 2, one pattern among a plurality of tool patterns (FIG. 4A) stored in the database 6 is read into the computer 4.

  Next, in S3 and S4, a slice (cut) process of the three-dimensional mold model and the work model read in S1 is performed. The contents of this processing will be described with reference to FIGS. FIG. 6 is a side view (a) of a three-dimensional shape mold model for explaining the die model slicing process, and a side view (b) of the work model for explaining the three-dimensional shape work model slicing process. FIG. 7 shows the slice cross section line of the mold model shown in FIG. 6A, the slice cross section line of the workpiece shape shown in FIG. It is a figure shown about each of surface 2 (b), slice surface 3 (c), and slice surface 4 (d).

  First, at S3, as shown in FIG. 6A, the three-dimensional mold model read at S1 is sliced horizontally at a predetermined interval (pitch) in the height direction ( Cut) processed. In the present embodiment, the slice is sequentially sliced from above, and the shape part 14 is sliced on the slice planes 1 to 3 and the mold part 16 is sliced on the slice plane 4. In the present embodiment, the pedestal 18 is not cut and is not sliced.

  Specifically, the slicing process in S3 extracts data having the Z coordinate (coordinate in the height direction) of the surface to be sliced from the coordinate data of the three-dimensional mold model, and is defined by the XY coordinates of the data The two-dimensional mold cross-sectional shape data of the cross section is generated. Then, as shown in FIGS. 7A to 7D, four (N = 4) cross-sectional lines (mold cross-section models) 20a indicating the outer shape lines of the mold cross-sections corresponding to the slice planes 1 to 4, respectively. , 20b, 20c, 20d.

  Next, in S4, as shown in FIG. 6B, the three-dimensional work model read in S1 is sliced. The height position, interval, and number of each slice surface are the same as the slice surface of the mold model in S3. In the slicing process in S4, data having the Z coordinate (coordinate in the height direction) of the surface to be sliced is extracted from the coordinate data of the three-dimensional work model in the same manner as in S3, and the XY coordinates of the data are extracted. The workpiece cross-sectional shape data of the two-dimensional shape of the cross section defined is generated. Then, as shown in FIGS. 7A to 7D, four (N = 4) cross-sectional lines (work cross-section models) 22a and 22b showing the outlines of the work cross-sections corresponding to the slice planes 1 to 4, respectively. 22c and 22d are obtained.

  Here, in the present embodiment, the interval between the slice planes is set to the machining depth (see FIG. 3) of the smallest diameter tool among all the tools included in the plurality of tool patterns read in S2. . That is, in general, when the machining load is taken into consideration, the machining depth decreases as the tool diameter decreases, so that the interval between the slicing surfaces is prevented from becoming larger than the machining depth in actual machining (a single cutting depth). It is. Therefore, it is possible to accurately compare the machining time by each tool pattern, and as a result, the tool use order set by the present embodiment can surely shorten the machining time.

Next, in S5, one slice plane to be processed in S6 to S12 below is selected. In this embodiment, selection is made in order from the upper slice plane.
Next, in S6, each cross-sectional shape model (each cross-sectional line) is superimposed on the slice surface selected in S5. As shown in FIG. 7, in the superposition process in S6, the cross-sectional models are superposed on predetermined reference coordinates, and as a result of this superposition, the cross-section to be processed (processed cross-section) as shown by the oblique lines in FIG. Part) 24a, 24b, 24c, 24d. In other words, the part obtained by removing the mold cross-sectional shape from the work cross-sectional shape is a cross-section to be processed. Is generated. By repeating the following steps S7 to S12, the processing time for processing the processed cross section according to a predetermined tool pattern is calculated.

  Next, in S7, one of the tools of the tool pattern read in S2 is selected according to the order of the tool pattern. That is, first, the tool with the earliest order (the tool with the largest diameter) is selected. For example, in the tool pattern (1) shown in FIG. 4A, a tool D20B is selected.

Next, in S8, a workable cross section and an uncut cross section are generated. The processing contents in S8 will be described with reference to FIGS. FIG. 8 is a diagram in which a mold cross-sectional shape and a work cross-sectional shape are overlapped for explaining a method of generating a workable cross-sectional portion and an uncut cross-sectional portion, and FIG. 9 is a drawing of each tool on each slice plane. It is a figure for demonstrating a possible cross-section part and a non-cutting cross-section part. 8A and 8B correspond to FIG. 7A showing the slice plane 1.
Here, depending on the size of the diameter of the tool, such as a small gap in the mold cross section and a small R at the corner, a portion that cannot be processed (uncut portion) occurs. In S8, a region that can be cut off by the tool (D20B) selected in S7 is generated as a workable cross-sectional portion of the processed cross-sectional portion (24a) in the slice surface (slice surface 1) selected in S5. A region that cannot be cut off is generated as a remaining cross-sectional portion. In this embodiment, when the tool is moved (swept) along the outer shape of the die cross section of the slice surface, a portion through which the tool does not pass is calculated based on the geometric relationship between the die shape and the tool diameter. In addition, the remaining cross-sectional portion is used.

First, as shown in FIG. 8A, the tool model 30 is moved along the outer shape of the die section model. The tool model 30 is a circular model having a diameter of 20 mm because the tool diameter is 20 mm in this case. Specifically, when the tool model 30 is moved along the outer shape of the mold cross section based on the coordinate data of the mold cross-sectional shape data obtained in S3 or the coordinate data of the machining cross-section data obtained in S6 The moving path and the area of the passing part are calculated. Since the part outside the part through which the tool model 30 passes can be processed by the tool, it is processed as the part through which the tool model 30 has passed.
8A, there is a portion where the tool model 30 does not pass between the tool model 30 and the mold cross-sectional model, and this portion is generated as a remaining cross-sectional portion. Specifically, data relating to the shape of the uncut cross section is generated as uncut cross section shape data. In this way, by moving the tool model along the mold section, the remaining uncut section can be easily and accurately generated. On the other hand, a portion other than the uncut cross section is generated as a workable cross section. Specifically, data relating to the shape of the workable cross-section is generated as the workable cross-sectional shape data.

Next, in S9, the area of the workable cross section is calculated from the data generated in S8. In the example shown in FIG. 8A, the area A1 (mm ² ) is calculated.
Next, in S10, the machining time of the workable cross section is calculated from the area calculated in S9 and the machining time per unit area of each tool stored in the database 6 (see FIG. 3). In the example shown in FIG. 8A, the machining time is calculated to be a1 (s) based on the machining area A1 (mm ² ) and the machining time d20t (mm ² / s) per unit area of the tool D20B. ing.

Next, in S11, if it is determined that there is an uncut cross section, the process proceeds to S12. In S12, if it is determined that there is a next tool in the tool pattern selected in S2, the process proceeds to S7. Returning, D12B which is the next tool is selected, and the processing of S8 to S10 is performed again.
In S8, as shown in FIG. 8 (b), the tool (D12B) selected in S7 is scraped out of the remaining uncut cross-sectional portion (see FIG. 8 (a) or FIG. 9) generated in S8 last time. A region that can be processed is generated as a workable cross section, and a region that cannot be cut off is generated as a remaining cross section. In this case, the tool model 32 having a diameter of 12 mm is moved along the outer shape of the die cross section in the same manner as in the process of S8 described above, and the newly processed cross-sectional shape data and the remaining uncut cross section corresponding to this step are newly obtained. Shape data is generated. In S9, the area of the cross-section that can be processed is calculated as A2 (mm ² ). In S10, as described above, the area A2 and the processing time d12t per unit area of the tool D12B (mm ² / s) Thus, the machining time is calculated to be a2 (s) (see FIG. 8B).

Such processes of S7 to S10 are repeated until it is determined in S11 that there is no uncut cross section or in S12 that there is no next tool. That is, the calculation is repeated for the tool having the tool pattern selected in S2 until there is no remaining uncut cross section. When there is an uncut cross section, but there is no next tool, the tool pattern (selected in S2) is not finally selected in S16 described later.
Here, the calculation result of the tool pattern (1) is shown in FIG. As shown in FIG. 9, the slice plane 1 has a D10 ball end mill, the slice plane 2 has a D6 ball end mill, the slice plane 3 has a D20 ball end mill, and the slice plane 4 has a D12 ball end mill. That is, there is no uncut cross section.

Next, until it is determined in S13 that there is no next slice plane, the processes of S5 to S12 are repeated for the other slice planes 2 to 4 in the same manner as described above.
When it is determined in S13 that there is no next slice plane, that is, when the processing for all slice planes 1 to 4 is completed, the process proceeds to S14, and each tool (D20B, D12B, D10B, D6B) are all added to the machining times in the slice planes 1 to 4, and the total machining time of the mold 12 in the tool pattern (1) is calculated.

  As shown in the calculation example in FIG. 9, the machining time t1 on the slice plane 1 is obtained by adding the machining times a1 to a3 of the three tools, and the machining time t2 on the slice plane 2 is calculated for the four tools. Each of the machining times b1 to b4 is obtained by adding the machining times t3 on the slice plane 3 to the machining time c1 by the tool D20B, and the machining times t4 on the slice plane 4 are machining times d1 and d2 by the two tools. It is obtained by adding together. And each processing time t1-t4 of each slice surface 1-4 is added together, and the total processing time T1 of a tool pattern (1) is calculated.

Next, the process proceeds to S15. If there is another tool pattern (see FIG. 4) in S15, the process returns to S2, and the same process as described above is performed for all the remaining tool patterns.
When the processes of S2 to S14 for all the tool patterns are completed, the process proceeds to S16, and the tool pattern to be used is determined. In S16, the total machining times T1, T2,... For each tool pattern calculated in S14 are compared, and the tool pattern with the shortest total machining time is extracted.
In this way, a tool pattern (order of use of machining tools) having the shortest total machining time in general machining can be automatically extracted by the computer 4 from a plurality of tool patterns. In particular, in the present embodiment, a three-dimensional mold model and a work model are sliced, and the machining time of each tool is calculated from the mold cross-sectional shape data and work cross-sectional shape data represented by two-dimensional data. Therefore, the calculation time is short, and as a result, it is possible to extract the optimum use order of the machining tools in a simple and short time.

Next, with reference to FIG. 10 and FIG. 11, processing for setting the tool usage order in the high-precision machining of the parting surface, which is performed following the processing of FIG. FIG. 10 is a flowchart showing the processing of setting the tool use order for high-precision machining according to the present embodiment, and FIG. 11 explains the cross-sections that can be machined and the remaining uncut cross-sections of each tool on the slice plane of the mold part. FIG. In FIG. 10, “S” indicates each step.
Here, the die-casting mold for molding the engine block and the like is constituted by a plurality of split molds according to the product shape. The plurality of split molds are generally formed with mold split surfaces having convex portions or concave portions for matching the molds, and by processing these mold split surfaces with high precision, Are combined with high precision so that the molten metal in the mold does not flow outside. In the present embodiment, the processing sequence shown in FIG. 10 sets the order of use of the processing tools that can process such a parting surface in a short time.

  In the processing flow shown in FIG. 10, first, in S <b> 20, the mold part is detected. Here, as shown in FIG. 2B, the mold parting surface of the mold part 16 is usually molded so that the gradient is 0 degrees, that is, it has a vertical parting surface. Accordingly, in S20, a region with a gradient of 0 degree is detected from the coordinate value in the height direction of the three-dimensional data of the mold model read in S1 (FIG. 5) described above, and the region portion (height direction) Is detected as a parting part.

  Next, in S21, detection of a corner portion existing in the mold part and the minimum value of R are calculated. As shown in FIGS. 2B, 2C, and 7D, the corner portion is a concave corner portion 16b on both sides of the convex portion 16a that protrudes in the horizontal direction in plan view. The portion 16b is formed with R smaller than the curvature of the convex portion 16a and R. In S21, a corner portion is detected from the coordinate value of the three-dimensional data of the mold model read in S1 (FIG. 5), and the minimum value of R of this corner portion is calculated.

Next, in S <b> 22, the high-precision machining tool pattern (FIG. 4B) stored in the database 6 is read into the computer 4. In S22, only a tool pattern including a tool capable of machining the minimum value of the corner R detected in S21 is read. For example, when the minimum value of the corner R is 5 mm, a tool pattern including a tool having a diameter of 10 mm or less is selected and read.
Next, in S23, the machining time for each tool pattern read in S22 is calculated. Here, since the slope of the mold part is 0 degree as described above, only one slice plane is set. In the present embodiment, the slice plane 4 is set as shown in FIGS. 6 (a) and 7 (d). With respect to this slice plane 4, the machining time for each tool pattern is calculated by the same process as the process of S6 to S12, S14 and S15 of FIG.

For example, as shown in FIG. 11, in the high-precision tool pattern (1) (see FIG. 4B), the machining time by the tool D20F (flat end mill) is e1 (s), and the tool D20F can be scraped off. It is calculated that the uncut remaining cross-sectional portion that could not be formed can be processed by the tool D10F in the processing time e2 (s). As a result, the total machining time of the high-precision tool pattern (1) is calculated by the calculation formula of Tf1 = e1 + e2. Such a process is performed for each tool pattern.
Next, in S24, the tool pattern with the shortest machining time is extracted from among the plurality of tool patterns in the same manner as the process of S16 in FIG.
In this way, even in a parting section where high machining accuracy is required, an optimal use order of machining tools can be extracted easily and in a short time by two-dimensional calculation processing. Furthermore, since the calculation is performed only for the tool pattern including the tool capable of machining the minimum value of R at the corner portion, the calculation time can be further shortened. Note that, in S2 of FIG. 5 described above, after detecting the size of the gap or the corner R, only a tool pattern including a tool capable of machining those portions may be selected.

  Next, in S25, the final tool pattern is determined by combining the general machining tool pattern extracted in S16 of FIG. 5 and the high precision machining tool pattern extracted in S24. The For example, in S16, the tool pattern (4) (D20B → D10B) shown in FIG. 4A is extracted, and in S24, the high-precision tool pattern (3) (D10F) shown in FIG. 4B is extracted. In this case, data relating to the tool usage order D20B → D10B → D10F is output (generated) as a final result and set as the tool order used in the NC machine tool 1. Based on the set data, the machining path or holder is determined as described above, and further converted into NC data.

1 is a schematic configuration diagram of an NC data generation system having a processing tool use order setting function according to an embodiment of the present invention. They are a perspective view (a) showing a three-dimensional shape work model according to the present embodiment, a perspective view (b) showing a three-dimensional shape product model, and a plan view (c). It is a figure which shows a part of tool information stored in the database by this embodiment. It is a figure which shows the data (a) for general machining of the tool pattern by this embodiment, and the data (b) for high precision machining. It is a flowchart which shows the process of the tool use order setting of the general machining by this embodiment. It is the side view (a) of the mold model for demonstrating the slice process of a mold model, and the side view (b) of the work model for demonstrating the slice process of a workpiece model. The slice cross section line of the mold model shown in FIG. 6A, the slice cross section line of the workpiece shape shown in FIG. 6B, and the cross section to be processed are slice plane 1 (a), slice plane 2 (b), slice plane. It is a figure shown about each of 3 (c) and slice surface 4 (d). It is the figure which overlap | superposed the metal mold | die cross-sectional shape and workpiece | work cross-sectional shape for demonstrating the method to produce | generate a processable cross-section part and an uncut part. It is a figure for demonstrating the processable cross-section part of each tool in each slicing surface, and a non-cutting cross-section part. It is a flowchart which shows the process of the tool use order setting of the highly accurate process by this embodiment. It is a figure for demonstrating the cross-section part which can be processed of each tool in the slice surface of a parting part, and an uncut cross-section part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 NC machine tool 2 NC data generation system 4 Computer 6 Database 10 Work model 12 Die model 16 Die part 20a-d Die section model 22a-d Work section model 24a-d Machining section 30, 32 Tool model

Claims (4)

A tool use order determination method for determining a use order of a plurality of rotating processing tools for processing a workpiece into a product shape,
A workpiece model indicating the three-dimensional shape of the workpiece, a product model indicating the three-dimensional shape of the product, and a plurality of tool order patterns in which the machining tools are arranged in a predetermined pattern in order from the large diameter to the small diameter, respectively. A process of storing in
A plurality of two-dimensional shapes showing a workpiece cross-sectional shape and a product cross-sectional shape when the work model and product model stored in the database are sliced at a plurality of surfaces at predetermined intervals in the height direction. Generating a workpiece section model and a plurality of two-dimensional product section models;
A step of superimposing the two-dimensional workpiece cross-sectional model and the two-dimensional product cross-sectional model on each other in each of the plurality of slice planes to generate a processed cross-sectional portion excluding the product cross-sectional shape from the work cross-sectional shape;
For each tool sequence pattern stored in the database, calculate the machining time of the portion that can be scraped with the tool with the maximum diameter of the tool sequence pattern, and generate a cross-sectional portion that remains uncut, Then, until the remaining cross-sectional portion does not exist, calculation of the machining time of the portion that can be scraped out of the remaining cross-sectional portion with a tool whose diameter is reduced in order according to the above-mentioned tool order pattern and further shaving Repeating the generation of the remaining cross-section,
Adding the machining time for each tool calculated in this step to calculate the total machining time for each tool sequence pattern, and extracting the tool sequence pattern with the shortest total machining time;
A method for determining the order of tool use.   2. The uncut cross-sectional portion is generated as a portion where the tool model between the tool model and the product cross-sectional shape when the tool model of the tool is moved along the product cross-sectional shape does not pass through. The tool usage order determination method described.   The tool usage order determination method according to claim 1, wherein the predetermined interval is the same as a machining depth of a tool having a minimum diameter in the tool order pattern. Uses a database that stores a workpiece model that shows the three-dimensional shape of the workpiece, a product model that shows the three-dimensional shape of the product, and a plurality of tool order patterns in which machining tools are arranged in a predetermined pattern from the largest to the smallest diameter. A tool use order determination program for a tool use order determination computer for determining a use order of a plurality of rotating processing tools for processing a workpiece into a product shape,
A plurality of two-dimensional shapes showing a workpiece cross-sectional shape and a product cross-sectional shape when the work model and the product model stored in the database are sliced on a plurality of surfaces at predetermined intervals in the height direction. Generate a workpiece cross-section model and multiple 2D product cross-section models,
In each of the plurality of slice planes, the two-dimensional workpiece cross-sectional model and the two-dimensional product cross-sectional model are overlapped with each other to generate a processed cross-sectional portion excluding the product cross-sectional shape from the work cross-sectional shape,
For each tool sequence pattern stored in the database, the machining time of the portion that can be scraped off with the tool having the maximum diameter of the tool sequence pattern is calculated and the remaining cross-sectional portion is generated, Then, until the remaining cross-sectional portion does not exist, calculation of the machining time of the portion that can be scraped out of the remaining cross-sectional portion with a tool whose diameter is reduced in order according to the above-mentioned tool order pattern and further shaving Let the generation of the remaining cross section be repeated,
The tool use order determination computer is configured to calculate the total machining time for each tool sequence pattern by adding the calculated machining times for each tool and to extract the tool sequence pattern with the shortest total machining time. Processing tool usage order determination program to be controlled.

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