JP3744708B2 - Processing cost estimation device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for estimating machining cost for machining when manufacturing a product using CAD data of the machined product.
[0002]
[Prior art]
The use of CAD (Computer Aided Design) is advancing to reduce design time and labor. In addition, a CAD / CAM (Computer Aided Manufacturing) system has appeared that intends to use data created by a CAD system for control of machine tools and the like in the manufacturing process in anticipation of automation up to the manufacturing process. In general, 3D shape data is required for manufacturing and processing, but with the recent progress in 3D CAD technology, CAD systems that can handle 3D data such as solid modelers have appeared, contributing to the realization of CAD / CAM. ing.
[0003]
CAD / CAM has been put into practical use, for example, in the field of mold design and manufacturing. In particular, in recent years, a parametric solid CAD that can change the model shape in conjunction with the change of the dimension parameters of each part has been used, and not only the efficiency of the design but also the sharing of data with the manufacturing process becomes possible. Yes.
[0004]
In order to meet the demand for manufacturing cost reduction, machining product design is required to be conscious of the processing cost (time required for processing, cost for processing, etc.). However, as a practical problem, it is difficult for even a skilled designer to satisfy the required level of machining cost with a single design. Therefore, in practice, after designing once with CAD or the like, an engineer estimates a processing cost and creates a process chart based on the design drawing, and gives feedback to the design as necessary. Estimating machining costs and creating process schedules require extensive and accurate knowledge of machining, so skilled engineers are required.
[0005]
[Problems to be solved by the invention]
In such a manual work, it takes several days until an estimation result is obtained, no matter how skilled a person is. For this reason, it may take an enormous time to obtain a suitable design by repeatedly modifying the design according to the estimate. If the design site cannot afford a schedule, it is difficult to reflect the estimation result in the design. In order to continue manual estimation, it is necessary to continuously train and maintain skilled workers who can make reasonable estimates.
[0006]
The present invention has been made to solve such a problem, and provides an apparatus for automatically estimating a machining cost necessary for machining from information on a product model of a CAD / CAM system. With the goal.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, an apparatus according to the present invention includes a roughness setting means for setting a roughness attribute for each machining target surface in a CAD model of a machined product, and a roughness set for each machining target surface. Cost estimation means for calculating a processing cost related to the processing target surface group of the product based on the height attribute.
[0008]
In machining that forms a product by cutting or polishing, the finishing roughness (accuracy) has a great influence on the processing cost. In this embodiment, by setting a roughness attribute on each machining target surface of the CAD model, the machining cost can be automatically calculated from the roughness attribute. The processing cost here includes both concepts of time required for processing and cost required for processing.
[0009]
Main departure In the light The cost estimation means includes grouping means for grouping processing target surface groups included in the CAD model into one or more surface groups by grouping adjacent processing target surfaces in the CAD model. According to the combination of the type determination means and the roughness attribute, the type determination means for determining whether the surface group belongs to the predetermined shape type based on the shape formed by the surface group A combination of the cost database storing the machining cost calculation rules, the shape type of the surface group obtained by the type determining means for each surface group, and the roughness attribute of each surface constituting the surface group A corresponding machining cost calculation rule is obtained from the cost database, and based on this rule, the machining cost of the surface group Calculated for containing the individual cost calculation means.
[0010]
The present invention Now, considering that the machining content (tool and procedure to be used) varies depending on the shape of the machining part, and this affects the machining cost, the machining cost should be calculated considering not only the roughness attribute but also the shape. did. In this aspect, a processing cost calculation rule is defined for each combination of shape type and roughness, and this is stored in a database (cost database). A processing site is defined as a group of adjacent processing target surfaces. For example, the shape type can be determined based on the number of faces belonging to this face group, their arrangement relationship, and the like. Then, from this shape type and roughness attribute, a cost calculation rule can be specified from the database, and the processing cost of the face group can be obtained using this rule. As the processing cost calculation rule, for example, a rate per unit area or unit processing time can be used. For example, when a rate per unit area is used, the processing cost is obtained by multiplying the rate by the area of the surface group.
[0011]
In a machine tool, the main machining direction is determined depending on how the workpiece is set, and the machining speed is maximized in this main machining direction. On the other hand, when the machining direction when forming the machining site is different from the main machining direction, the machining speed is slowed down. In particular, when the machining direction is oblique to the main machining direction, the machining speed becomes considerably slow. In consideration of the above, it is also preferable to subdivide the machining cost calculation rule according to the orientation of the surface group with respect to the main machining direction.
[0012]
In addition, for a part having a standard shape that can be processed by the same processing method and appears relatively frequently in a product, the processing cost is determined if the type of the part is determined. Therefore, if these standard parts are classified by type, the calculation rules for machining costs are made into a database for each type, and if the type is set as an attribute in the special machining part of the CAD model at the design stage, the database Therefore, the processing cost of the special processing site can be obtained. The above-described method based on the roughness attribute of the surface to be processed has the advantage that it can be applied to any shape of the part, but the special processing part method is simpler in calculation processing. Therefore, efficient estimation processing can be realized by combining both methods.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention (hereinafter referred to as embodiments) will be described with reference to the drawings. Hereinafter, a processing cost estimation system in the design of a press working die will be described as an example. However, as will be apparent from the following description, the method of the present embodiment can be applied not only to a press mold, but also to products manufactured by machining such as cutting and polishing.
[0014]
[System configuration]
FIG. 1 is a functional block diagram showing a schematic configuration of a machining cost estimation system according to the present invention. In FIG. 1, a CAD system 10 is a solid modeler capable of changing a model shape parametrically. Mold CAD data 12 created using the CAD system 10 includes solid model data representing the shape of the mold and attribute data set for each component of the solid model.
[0015]
<Processing attributes>
As is well known, in a solid model, the components constituting one product (object) are geometrical concepts such as vertices, sides (edges), faces, and shells (areas surrounding a space, defined by multiple faces). Organize and manage each level. Each component is given unique identification information (hereinafter referred to as “ID”), and each component can be designated and referred to by this ID.
[0016]
The CAD system 10 has a mechanism for setting various kinds of attribute data for the constituent elements of such an object. Various types of attribute data can be set for the constituent elements, but the roughness attribute and the special machining part type attribute are related to the cost estimation of machining that is the object of this embodiment.
[0017]
The roughness attribute is the roughness of the target surface when processing the surface, and is also called finishing accuracy. Accordingly, the roughness attribute is set for the surface. However, the roughness attribute is not necessarily set for all the faces of the solid model, but is set only for the faces to be processed. In the case of a mold, each surface is formed from a casting by machining such as cutting and polishing, but the roughness attribute is set only for the surface on which such machining is performed.
[0018]
The special machining site type attribute is an attribute given to a component corresponding to a predetermined special machining site type among the components of the solid model.
[0019]
The mold is provided with standard parts having a predetermined shape and size, such as guide post holes and press mounting seats. The content of processing is determined for such a standard part, and the time required for processing is also known. In the present embodiment, such a standard part is called a specially processed part and is classified into types such as a guide post hole and a press mounting seat. In the design in the CAD system 10, when such a standard part is provided, a special processing part type such as a guide post hole is set as attribute data of the part.
[0020]
FIG. 2 is a diagram illustrating an example of the data content of the roughness attribute included in the CAD data 12. In this data, an ID (surface ID) in CAD data and a set value of roughness attribute (such as ▽ and ▽ ▽) are set for each surface to be processed. FIG. 3 is a diagram illustrating an example of the data content of the special machining part attribute included in the CAD data 12. In this data, an ID (part ID) and a special processing part type (such as a guide post hole) in CAD data are set for each part. Here, although the roughness attribute and the special machining site attribute are shown in separate drawings, this means that the roughness attribute and the special machining site attribute are not necessarily held separately in the CAD data 12. Instead, they may be held together in the attribute data area of each component in the CAD data.
[0021]
<Processing cost estimation processor>
The machining cost estimation processing unit 14 refers to a machining database (hereinafter, “database” is abbreviated as “DB”) 20 based on CAD data in which such a roughness attribute and a special machining site attribute are set. Estimate the processing cost (processing time and processing cost) of the mold. The processing DB 20 includes five types of DBs: a shape type determination rule DB 21, a surface processing part DB 23, a special processing part DB 25, a work code DB 27, and a processing unit price DB 29. In the estimation process of the machining cost estimation processing unit 14, the machining cost is calculated for each of the surface group having the roughness attribute set (that is, the surface to be processed) and the region group having the special machining site attribute set. The total is taken as the overall machining cost of the mold.
[0022]
(1) Machining cost of target surface group
The processing cost of the processing target surface group is basically obtained from the roughness attribute and area of each surface. This is because, in machining, the unit price (time and cost) required for machining per unit area differs depending on the value of roughness (finishing accuracy). More precisely, the shape and size of the machining site (area or volume to be cut), the orientation of the machining site with respect to the main machining direction of the machine tool (referred to as the main machining direction), or the type of the mold to be designed (above Depending on the tool, lower mold, pad, etc.), the cutting tool to be used, the processing procedure (how to move the machine tool, etc.), and the machine tool are different, which leads to a difference in cost.
[0023]
A processing site is defined as a collection of adjacent processing target surfaces. Such a group of adjacent processing target surfaces is called a surface group. The shape of the processed part is the shape of this surface group. In this embodiment, the shape of this surface group is classified into a plurality of predetermined shape types. This is a classification of shapes appearing in mold production, taking into account the processing method required to form the shapes.
[0024]
For example, there are various types of shapes including “wall-less surface” shown in FIG. 4 and “engraved” shown in FIG. The determination of the shape type is determined from the number of surfaces constituting the surface group, the topological arrangement relationship of each surface, the shape and size of each surface, and the like. For example, if the number of surfaces of a certain surface group is 1 (that is, there is no adjacent surface) and the shape of the surface is flat, the shape type of the surface is “wallless surface”. In addition, the shape type “engraved (three sides)” illustrated in FIG. 5 is a shape that is formed when a corner portion where two surfaces intersect is squarely carved, and is adjacent to one surface in a certain surface group. When there are three vertical surfaces, this surface group is classified into the shape type “engraved (3 surfaces)”. Such a rule for determining the shape type is registered in the shape type determination rule DB 21, and the machining cost estimation processing unit 14 refers to this DB 21 to determine the shape type of each surface group.
[0025]
In the present embodiment, the processing parts are classified into a plurality of processing types based on the shape type of the processing part, the orientation with respect to the main processing direction, the finishing roughness and the size (area), and each processing type has a unit per unit area. A processing time (referred to as a unit processing time) is determined and stored in a database. This DB is the surface processing part DB23. In order to obtain the machining time of a certain machining site (surface group), the unit machining time is obtained from the shape, orientation, finish roughness, and size of the machining site, and the unit machining time is multiplied by the area of the machining site. .
[0026]
FIG. 6 shows an example of the data contents of the surface machining site DB 23 in a table format. In this table, each machining type is assigned a number for identification. Each machining type has four factors: shape type, “orientation” with respect to the main machining direction, finishing roughness, and size (area). Classified by combination. When these four factors are determined, the type of processing (that is, the blade used for processing, the processing procedure, etc.) is determined, and accordingly, the processing time per unit area (unit processing time) can be determined.
[0027]
That is, the shape type is the shape of the processed part, and greatly affects the difficulty of processing. In this respect, the “direction” with respect to the main machining direction is the same. The “direction” here is the direction of the machining direction when machining the machining site with respect to the main machining direction. For example, in the case of a surface without a wall (see FIG. 2), the direction perpendicular to the surface is the processing direction. If this direction is the same as the main processing direction, the surface is “front”, and the direction is the main processing direction. If it is vertical, it becomes “side”. When the processing site is a hole such as a drill hole or a through hole, the direction of the center axis of the hole is the processing direction, and the direction with respect to the main processing direction is the “direction” here. When the processing direction of the processing site matches the main processing direction, the processing is easiest, and the time required for processing is short. When the processing direction is perpendicular to the main processing direction, the processing is generally easier next. When the machining direction is oblique to the main machining direction, the control of the machine tool becomes the most complicated, and the time required for machining becomes the longest.
[0028]
The finishing roughness affects the cutting time to be used, its feed speed, the processing procedure, etc., and therefore the processing time. Of course, the rougher the finish, the shorter the unit machining time. Further, it is well known that the cutting tool to be used, the machining conditions, and the like change depending on whether the area of the machining site is large or narrow, and the size of the machining site also affects the unit machining time.
[0029]
In FIG. 6, the unit processing time is a unit area (for example, 100 cm). ² ) The processing time required for winning is expressed in “hour” units. According to the table of FIG. 6, for example, it was found that the shape type is “no wall”, the orientation is “front”, the finish roughness is “▽▽”, and the size is “less than 100” for a certain processing part (surface group). In this case, it can be seen that the unit processing time for processing the part is 0.08 hours. By multiplying this by the area of the processed part (for example, the total area of the surface group constituting the processed part), the processing time required to process the part is obtained. Then, if the machining times obtained for all the surface groups are summed, the machining time for the entire machining target surface group of the product can be obtained.
[0030]
In the above, the processing types are classified according to four factors. However, it is not necessary to consider all combinations of these four factors, and in the case of a mold, only the combinations that appear in the mold design need be considered. For example, in the case of a product that does not engrave holes diagonally, the direction of “diagonal” for the shape “hole” need not be considered. Therefore, the processing type corresponding to such a combination does not have to be registered in the surface processing portion DB 23.
[0031]
In addition, the above-described classification of processing types based on the four factors is merely an example, and various modifications are possible. For example, in addition to these four factors, it is also possible to further classify by work material. This is because the cutting tool and other processing conditions change depending on the material, so the unit processing time also changes. When designing a plurality of products with different materials, it is also necessary to consider the materials.
[0032]
Although the processing time has been described above, another factor is added in the case of processing costs. It is the type of mold part to be designed (upper mold, lower mold, pad, etc. This classification is called mold part type). That is, if the mold part type is different, various conditions such as a machine tool to be used and a work setting method are different, which leads to a difference in machining cost. For example, a relatively large mold part such as an upper mold or a lower mold is processed almost automatically by a large NC machine tool, whereas a small mold part is processed manually by a small machine tool. Often. Here, the case where the former and the latter process the part of the same processing type is considered. In this case, since the processing time is the time required for physical processing such as cutting and polishing, the rate (unit processing time) hardly changes even if the machine tool is different if the processing type (content of processing) is the same. On the other hand, in the case of machining costs, the rate (unit cost of machining) varies depending on the type of machine tool used, particularly whether it is automatic or manual operation is required. That is, the latter requires more labor costs than the former, which causes a difference in processing unit price. Therefore, in this embodiment, the types of work are classified according to the processing type and the mold part type, and the processing unit price is determined for each type of work. The work code DB 27 registers information for classifying the work types, and the processing unit price DB 29 registers the processing unit price for each type of work.
[0033]
FIG. 7 is a diagram showing the data contents of the work code DB 27 in a table format. The work code is a code uniquely assigned to each kind of work, and it is preferable that the work code is determined so that it can be used in a CAM system that is the downstream of the system. As can be seen from the figure, a work code is defined for each combination of the processing type and the mold part type. The mold part type is a code assigned to each type of mold part. For example, the mold part types “52” and “62” indicate an upper mold and a lower mold, respectively. When the processing type is “001” (no wall, front,...) And the processing target is the upper mold “52” or the lower mold “62”, both the work codes are “J22”. This is because the upper die and the lower die can be machined with the same machine tool and machining conditions for the machining type “001”, and therefore the work contents are the same. On the other hand, if the mold part type is the pad “32” even if the machining type is “001”, the machine type or machining conditions used for machining changes, so the type of work changes, and the work code is classified into a different work code “DT”. Will be.
[0034]
FIG. 8 is a diagram showing the data contents of the processing unit price DB 29. As illustrated, the processing unit price DB 29 stores a processing unit price (that is, a processing cost per unit time) for each work code.
[0035]
Therefore, in order to obtain the machining cost of a certain machining part (surface group), the work code is obtained by referring to the work code DB 27 from the machining type and mold part type of the part, and then the machining unit price corresponding to the work code is determined. What is necessary is just to multiply from the machining unit price DB 29 and multiply this machining unit price by the machining time of the machining site obtained by the above-described method.
[0036]
As described above, the processing unit cost per unit time is used to obtain the processing cost because the processing cost includes a cost factor such as a labor cost. On the other hand, the processing time is purely the time required for physical processing by the machine tool, and can be determined from the processing content (ie, processing type) and the amount of processing (ie, processing area).
[0037]
In the above, the unit machining time is determined for each machining type, but if the machining type is common, the machining time per unit area is almost the same even if the conditions such as the type of machine tool used are different. Because it became. On the other hand, if the unit machining time varies greatly depending on the type of machine tool even in the same machining type, the unit machining time is determined for each work code, not for each machining type. . Such a case is also included in the scope of the present invention.
[0038]
(2) Processing cost for special processing parts
Next, how to determine the processing cost of the special processing site group will be described.
[0039]
The processing cost of the above processing target group is determined by the processing type and processing area determined by the shape and orientation of the part, finish roughness, size, etc., and the processing cost depends on the processing type and mold part type. Determined from fixed work code and machining time. In this way, in order to obtain the processing cost of the processing target surface group, the processing target surfaces are grouped and the shape is determined for each surface group, and further, the processing type is determined from conditions such as the shape and the finish roughness. Many steps were required.
[0040]
On the other hand, since the special machining site has a predetermined shape, size and other machining conditions, the processing can be further simplified. For example, in the case of a specially processed portion of the type “guide post hole”, the shape, size, finish roughness, and orientation are determined, so that the processing time per one portion is also known. If the processing time (per unit area, not per unit area) is compiled in a database for each type of special processing site, the processing time is obtained from the type of the special processing site. be able to. This database is the special processing site DB 25 of FIG.
[0041]
FIG. 9 shows an example of the data content of the special processing site DB 25. As shown in the drawing, the machining time per piece is registered in the special machining site DB 25 for each special machining site type. This DB can be made more detailed. For example, when there are a plurality of sizes in the guide post hole, each size may be regarded as a different type and the processing time may be registered for each size.
[0042]
Therefore, if the CAD data 12 includes a special processing part, the processing time can be obtained by referring to the special processing part DB 25 from the special processing part type of the part. If there are a plurality of special machining parts of the same type, the machining time of that type is accumulated for the number of times, and the total machining time of the special machining parts group of the same type is obtained.
[0043]
As can be seen from the above description, the special machining site type can be said to be equivalent to a combination of the machining type of the surface machining site DB 23 (see FIG. 6) and the area of the machining site. Of course, it is possible to apply the same method as the cost calculation of the above-described processing target surface group for the special processing part, but in this embodiment, in order to reduce the estimated processing time as much as possible, for the standardized part, It made it easier to calculate.
[0044]
As for the machining cost of the special machining part group, it is necessary to consider the mold part type as in the case of the above-described machining target surface group. That is, in the case of the special machining part group, as in the case of the machining target surface group, the work code is classified according to the machining type (that is, the special machining part type) and the mold part type, and the machining unit price is determined for each work code . The reason for doing this is the same as in the case of the cost calculation of the surface group to be processed as described above, and a description thereof will be omitted.
[0045]
Therefore, in the system of the present embodiment, the table similar to FIG. 7 is also registered in the work code DB 27 for the special machining site group (in this case, the special machining site type corresponds to the “machining type” in FIG. 7). The processing unit price corresponding to each work code is registered in the processing unit price DB 29. Here, for the sake of clarity, the special processing site type is indicated by a name such as “guide post hole”, but this type may be expressed by an identification number as in the case of the processing type.
[0046]
The machining cost can be obtained by multiplying the machining unit cost obtained from the work code DB 27 and the machining unit price DB 29 by the machining time obtained by the above-described method. By summing up the machining costs obtained in this way for all the special machining sites, the machining costs for the previous special machining sites are obtained.
[0047]
[Processing procedure]
Next, a processing cost estimation process according to this embodiment will be described with reference to a flowchart.
[0048]
<Overall>
First, an overall processing procedure will be described with reference to FIG.
[0049]
First, the designer designs the shape of the mold by the CAD system 10 capable of changing the shape parametrically (S10). Next, on the CAD system 10, the designer sets the roughness attribute and the special machining part attribute for the solid model formed by the shape design (S12, S14). The roughness attribute is set for the surface to be processed among the surfaces of the model, and the attribute value is the level of finishing roughness. The special machining site attribute is set for a site corresponding to any one of the special machining site types, and the attribute value is the special machining site type. The attribute data set in this way is held in the CAD data 12. The process so far is the processing in the CAD system 10.
[0050]
When the setting of the shape design, the roughness attribute, and the special machining part attribute is completed, the estimation process in the machining cost estimation processing unit 14 is started. In this estimation process, the operator first inputs preconditions for estimation such as the mold part type and the main machining direction (S16). That is, the mold to be estimated from now corresponds to any mold part type such as upper mold, lower mold, pad, etc., and which direction the main machining direction at the time of machining work is with respect to the solid model, Etc. are input. The mold part type and the main machining direction cannot be automatically determined only from CAD data (shape and various attribute data), and thus are manually input. Of course, these estimation conditions may be preset in the CAD system 10.
[0051]
When the input of the estimation condition is completed, the estimation process is started. In the present embodiment, the estimation for the surface group (that is, the processing target surface group) for which the roughness attribute is set and the estimation for the region group for which the special processing part attribute is set are conceptually divided. Here, the former is referred to as surface machining estimation processing (S20), and the latter is referred to as special machining estimation processing (S30). Details of the processes of S20 and S30 will be described later. In any case, according to S20, the total machining cost for the surface group for which the roughness attribute is set can be obtained, and according to S30, the total machining cost for the part group for which the special machining site attribute is set is obtained. be able to. Since the processes of S20 and S30 can be performed completely independently, the execution order of these processes is not limited to the illustrated one.
[0052]
When both the surface machining estimation process (S20) and the special machining estimation process (S30) are completed, the estimation results of both are integrated to obtain the machining cost of the entire mold (S40). This gives you the total cost of machining to make the mold. This is output as a mold machining cost.
[0053]
In the system of this embodiment, in addition to the total processing cost, original data for creating a process chart for mold production is output. This process table original data may simply be a list of combinations of work codes and machining times for each machining site. For special machining parts, even if there are a plurality of parts of the same type, only the routine processing is repeated. Therefore, the work code and the machining time may be totaled for each type rather than for each machining part. Since the work code and the processing time information can be obtained in the course of the estimation process, this is used as the process table original data. In the downstream process design, the designer determines an appropriate work order while looking at the original data, and creates a process table.
[0054]
By such a series of procedures, the processing cost and the process table original data 30 (see FIG. 1) for processing the mold are obtained.
[0055]
The overall flow of the estimation process of this embodiment has been described above. When the total machining cost of the mold is obtained by such processing, it is possible to determine whether or not the given CAD model is designed to satisfy the requirements for the machining cost by comparing this with the target amount.
[0056]
Next, details of the surface machining estimation process (S20) and the special machining estimation process (S30) will be described in order.
[0057]
<Surface processing estimate>
The detailed procedure of the surface processing estimation process (S20) is shown in FIG. In this procedure, first, a processing target surface is extracted from the CAD data 12 (S202). The surface to be processed is a surface having a roughness attribute set. The processing cost estimation processing unit 14 examines attribute data of each surface of the CAD data 12 (solid model), and extracts a surface having a roughness attribute set as a processing target surface.
[0058]
Next, the processing cost estimation processing unit 14 groups the extracted processing target surface groups by paying attention to the adjacent relationship between the surfaces (S204). In this process, the processing target surface adjacent to the processing target surface is extracted with reference to the CAD data 12 for each extracted processing target surface. Thereby, for each surface to be processed, a surface (referred to as a reference surface) and a surface to be processed adjacent to the surface (referred to as an adjacent surface, which may or may not be one or more). A face group consisting of
[0059]
In this stage of S204, since the adjacent surface group is grouped for each processing target surface, the same surface may be included in a plurality of surface groups. The face group at this stage is called an extracted face group. FIG. 12 is a diagram illustrating an example of the data contents of the extraction plane group group. In this example, the ID of the reference surface (ID of that surface in the CAD data) is shown for each surface group, and the IDs of adjacent surfaces adjacent to it are listed. Since the surface group of the adjacent surface is obtained for each processing target surface extracted in S202, each processing target surface is a reference surface of one of the surface groups. For example, consider the example of the surface group of the surface to be processed that constitutes the processing portion of “3 engraving surfaces” shown in FIG. The numbers in parentheses on each surface in FIG. 5 indicate the ID of that surface. In this part, the surface group when the surface of ID 45 is noticed is group 1. In this case, the surface of ID45 is a reference surface, and each surface of ID62, 75, and 76 is an adjacent surface. On the other hand, when attention is paid to the surface of ID62, a group k is formed. In this case, with respect to the reference surface of ID62, the adjacent surfaces are only the surfaces of ID45 and 75 (the surface of ID76 is not an adjacent surface when viewed from the surface of ID62).
[0060]
As described above, when a group of adjacent surfaces is formed by paying attention to each surface to be processed, one surface may belong to a plurality of surface groups (see group 1 and group k in FIG. 12). . Therefore, in this embodiment, the surface group to which the same surface belongs is thinned out so that one surface belongs to only one surface group (S206). This is because, in the present embodiment, one surface group is regarded as one processing part to which the same processing content is applied. The thinning process in S206 is performed based on various conditions.
[0061]
One of the conditions is that a surface having a large number of faces constituting the face group is left. This condition can be understood from the comparison between the above-described group 1 and group k in FIG. 12 (refer to FIG. 5 for the shape of the corresponding portion). That is, the group 1 and the group k are the same except for whether or not the ID76 plane is included. In this case, the group k is thinned out according to the above conditions. If the shape shown in FIG. 5 is to be processed, the surface of ID76 cannot be processed separately from the other three surfaces (if this is done, the efficiency will be very low). Sex will be understood.
[0062]
Further, as another thinning-out condition, a condition relating to the orientation of the reference surface with respect to the main machining direction can be used. This condition is that the surface group in which the normal direction of the reference surface coincides with the main machining direction has the highest priority, the one perpendicular to the main machining direction has the second highest priority, and is oblique to the main machining direction (although parallel or vertical) However, it is a condition that only the face group with the highest priority is left, with the case of 3rd priority. This condition can be used as a condition for determining which of the plurality of face groups having exactly the same construction surface to leave. For example, in the case of the shape of FIG. 5, the surface group (group 1 in FIG. 12) whose surface is ID45 and the surface group whose surface is ID75 are both the number of surfaces and the surfaces constituting the group. Exactly the same. In such a case, since the normal direction of the reference surface (ID45) matches the main machining direction (that is, has the highest priority), the group 1 is selected and the group having the ID75 surface as the reference surface is Will be drawn.
[0063]
As described above, the orientation of the reference surface with respect to the main machining direction is taken into consideration in the thinning-out condition in order to leave the one with the lowest machining cost (machining time and cost is low). That is, the shape shown in FIG. 5 can be processed by processing along the main processing direction or by processing along the direction perpendicular to the surface of the ID 75, but it can be processed along the main processing direction. Therefore, the processing speed is faster (moreover, work such as re-setting of the work is less likely to occur), so the surface group that matches the direction is selected.
[0064]
When the thinning process according to such a thinning condition is completed, the shape type is determined for each remaining surface group (referred to as a thinned back surface group) (S208). This determination is performed according to the procedure described above according to the rules of the shape type determination rule DB 21. By this process, the shape type is determined for each surface group (that is, the processing site). At this time, the finishing roughness of the surface group is obtained from the roughness attribute value of each surface constituting the surface group at the same time. Further, the “direction” of the surface group can be determined from the relationship between the normal direction of the reference surface of each surface group and the main machining direction.
[0065]
Once the shape type is determined, the processing area is then determined for each thinned back surface group (S210). This processing area is, for example, the total area of the surface group constituting the surface group. The processing area can be obtained from information on each surface of the CAD data 12. Note that either the shape type determination (S208) or the processing area calculation (S210) may be performed first.
[0066]
When the shape type and the machining area of each thinned back surface group are obtained, the machining time of each group is obtained (S212). As described above, the processing time is obtained by determining the unit processing time in the surface processing portion DB 23 from factors such as the shape type, orientation, finish roughness, processing area (these are determined in the steps so far), It can be obtained by multiplying the unit machining time by the machining area. In this step, the processing type of each surface group can be specified in the process of obtaining the processing time of each surface group.
[0067]
When the processing time and processing type of each thinned back surface group are obtained, an operation code is assigned to each surface group (S214). In this step, as described above, the work code assigned to each face group by referring to the work code DB 27 from the machining type of each face group and the type of mold part (upper mold, lower mold, etc.) to be designed. To decide.
[0068]
When the assignment of the work code is completed, the machining cost is calculated from the work code of each thinned rear face group and the machining time of each face group obtained in S212 (S216). In this step, for each thinned rear surface group, a processing unit price corresponding to the work code of the group is obtained from the processing unit price DB 29, and this processing unit price is multiplied by the processing time of the surface group. Thereby, the processing cost of each surface group is calculated | required. By summing up the machining costs of these individual surface groups, machining costs for the entire design target mold (except for costs for special machining parts) are required.
[0069]
By such a processing procedure, the total processing cost required for processing the surface group for which the roughness attribute is set is obtained. Also, as a by-product of this processing procedure, the work code and processing time can be found for each group of faces, so if this information is output in a list, for example, it can be used as the original data that forms the basis for creating the process chart Can do.
[0070]
<Special processing estimate>
Next, the detailed procedure of the special processing estimate (S30) will be described with reference to FIG.
[0071]
This procedure starts from extracting a part having a special machining part attribute set from the CAD data 12 (S302). In the special machining part attribute, a special machining part type such as “guide post hole” is set. In this step, the type is obtained for each special machining part.
[0072]
Next, based on the information on the type of each special machining site, the machining time is calculated with reference to the special machining site DB 25 (S304). Since the special machining site DB 25 holds information on the machining time per piece for each special machining site type, the machining time for each special machining site can be known by referring to this. Special processing parts have a fixed shape, and if the type is the same, the processing content is exactly the same, so if there are multiple special processing parts of the same type in the target mold, they will continue. It is more efficient to process at once. Therefore, the machining time in this step is totaled for each special machining site type. That is, for each type, the machining time for each type is obtained by multiplying the machining time per piece by the number of pieces.
[0073]
When the machining time is obtained, the work code to be assigned to each special machining site type is determined by referring to the work code DB 27 from the special machining site type and the type of mold part to be designed (S306). This processing may have the same processing contents as the above-described surface processing estimation S214.
[0074]
When the work codes are assigned in this way, the machining cost is calculated from the work codes of each special machining site type and the machining times of those types determined in S304 (S308). In this step, by referring to the machining unit price DB 29 from the work code of each special machining part type, a machining unit price corresponding to the code is obtained, and this machining unit price is multiplied by the machining time of each type, thereby obtaining individual types. Ask for the processing cost. Then, the total machining cost of the special machining site group can be obtained by summing up the machining costs obtained in this way for all the special machining site types. Even in this procedure, the original data for the process chart can be obtained as a byproduct of calculating the total processing cost.
[0075]
By integrating the results of the surface machining estimation process (S20) and the special machining estimation process (S30) described above, the total machining cost of the mold to be designed can be obtained.
[0076]
[Mold design support integration system]
The system for estimating the processing cost has been described above. Next, a mold design support integrated system incorporating this estimation system will be described.
[0077]
FIG. 14 is a functional block diagram showing an overall image of the mold design support integrated system. In this system, the processing cost estimation processing unit 14 and the processing DB 20 constitute the processing cost estimation system already described. This integrated system has a purchase cost estimation system in addition to the processing cost estimation system, and can determine the total cost (referred to as mold cost) necessary for manufacturing the mold.
[0078]
That is, in the mold, the main part is manufactured by machining a casting or the like, but in addition, fine standard parts such as attachments are required. These parts can be covered by purchasing off-the-shelf products. Whether or not the mold can be manufactured within the budget must be determined not only by the processing cost but also by the mold cost including the purchase cost. This integrated system is an apparatus for checking such a mold cost.
[0079]
In this integrated system, the mold cost estimation unit 13 includes a processing cost estimation mechanism and a purchase cost estimation mechanism. The former is composed of the CAD system 10, the CAD data 12, the machining cost estimation processing unit 14, and the machining DB 20, and since the procedure has already been described, the description thereof is omitted here.
[0080]
On the other hand, the purchase cost is estimated by the purchase cost estimate processing unit 15 with reference to the purchased product DB 40. The unit price of each ready-made part is registered in the purchased product DB 40. The purchase cost estimation processing unit 15 detects the name of each ready-made part from the CAD data 12, obtains the unit price of each ready-made part from the purchased product DB 40 based on the name, and sums the unit price for all parts. Find the total purchase cost. Depending on the part, additional processing may be requested from the supplier, and the cost of such additional processing is estimated by the operator, for example, and input to the purchase cost estimation processing unit 15, and this is reflected in the total purchase cost. Is done.
[0081]
The total processing cost and the total purchase cost obtained in this way are totaled by the mold cost check processing unit 16 to obtain the mold cost. Then, the mold cost check processing unit 16 compares the determined mold cost with a previously registered mold cost target. Then, the mold cost check processing unit 16 determines that the design indicated by the CAD data 12 satisfies the target when the mold cost is within the allowable range of the mold cost target. Result data 50 such as data and mold costs is output. On the other hand, if the determined mold cost exceeds the allowable range of the mold cost target, a message that the CAD data 12 should be corrected is sent to the CAD system 10.
[0082]
With such an integrated system, it is possible to quickly determine whether the mold design satisfies the target budget, and it is possible to provide feedback to the design so that it is within the budget.
[0083]
Here, since the CAD system 10 is a solid modeler whose shape can be changed parametrically, when the target budget is exceeded, the design can be easily changed by changing some dimensions.
[0084]
[Others]
The embodiment of the machining cost estimation system according to the present invention and the mold design support integration system incorporating this system has been described above.
[0085]
As described above, in this embodiment, a roughness attribute is set on the machining target surface of the CAD model, and a machining cost (machining time and machining cost) is obtained based on the information on the roughness attribute. In particular, in the present embodiment, focusing on the shape type and roughness attribute of each machining part, the machining content (machining type) necessary for each part is made into a database, so that machining of each machining part is automatically performed from CAD data. The type can be determined. Since the rate of processing time and processing cost is determined according to the determined processing type, the processing time and processing cost can be obtained from the rate. In this embodiment, the processing cost rate (processing unit price) is determined in consideration of not only the processing content but also the mold part type. This makes it possible to perform detailed machining cost calculations corresponding to the case where the machine tool to be used differs depending on the characteristics of the production target.
[0086]
Further, in this embodiment, for a part that can be formed with a standard processing content (special processing part), instead of estimating with the above-described roughness and area, a more simplified estimation with a rate per part is performed. Since this is possible, the processing cost can be estimated faster.
[0087]
As described above, according to this embodiment, it is possible to automatically estimate the processing cost and the die cost, and to feed back the estimation result to the design, so that it is possible to reduce the processing cost and the die cost. become.
[0088]
Further, the roughness attribute and special machining part attribute of the machining target surface set in the present embodiment can be used for NC calculation in the CAM system downstream of the system.
[0089]
In the embodiment described above, the processing cost rate, that is, the unit processing time and the processing unit price are stored in a database, but this is only an example. In order to estimate the machining cost, it is only necessary to know the calculation rules for the machining cost. Therefore, it is also preferable to create a database of the calculation formulas. For example, if a certain initial cost and a certain amount of cost depending on the repetition are required to repeat a certain process, the process cost cannot be calculated on a simple unit price basis. The calculation rule may be registered in the database instead of.
[0090]
In the above example, one processing type (processing content) is associated with one work code. However, there are cases where a plurality of operations are required when trying to form a site of one processing type. For example, in the case of a site that requires a very precise finish, in addition to rough machining, several stages of finish polishing may be required. In such a case, one processing type may be mapped to a plurality of work codes representing a plurality of necessary works. For such machining types, for example, a rule for calculating a unit machining time for each operation may be registered in a database such as the surface machining site DB 23.
[Brief description of the drawings]
FIG. 1 is a functional block diagram showing a schematic configuration of a machining cost estimation system according to the present invention.
FIG. 2 is a diagram illustrating an example of data content of roughness attributes included in CAD data.
FIG. 3 is a diagram showing an example of data contents of special machining site attributes included in CAD data.
FIG. 4 is a diagram illustrating an example of a shape type.
FIG. 5 is a diagram showing another example of a shape type.
FIG. 6 is a diagram showing an example of data contents of a surface machining part DB in a table format.
FIG. 7 is a diagram showing an example of data contents of a work code DB in a table format.
FIG. 8 is a diagram showing an example of data contents of a processing unit price DB.
FIG. 9 is a diagram showing an example of data contents of a special processing site DB.
FIG. 10 is a flowchart illustrating an overall processing procedure of the estimation system according to the embodiment.
FIG. 11 is a flowchart showing a detailed procedure of surface machining estimation processing.
FIG. 12 is a diagram illustrating an example of data content of an extraction surface group.
FIG. 13 is a flowchart showing a detailed procedure of special processing estimation processing.
FIG. 14 is a functional block diagram illustrating an example of a die design support integration system incorporating the machining cost estimation system according to the embodiment.
[Explanation of symbols]
10 CAD system, 12 CAD data, 13 mold cost estimation unit, 14 machining cost estimation processing unit, 15 purchase cost estimation processing unit, 16 mold cost check processing unit, 20 machining DB, 21 shape type determination rule DB, 23 surface machining site DB, 25 Special processing part DB, 27 Work code DB, 29 Processing unit price DB, 30 processing cost and original data for process table, 40 purchased product DB.

Claims (5)

Roughness setting means for setting a roughness attribute for each machining target surface in the CAD model of the machined product;
Cost estimation means for calculating a processing cost related to the processing target surface group of the product based on the roughness attribute set for each processing target surface;
Only including,
The cost estimating means includes
Grouping means for grouping adjacent processing target surfaces in the CAD model into one or more surface groups by grouping processing target surface groups included in the CAD model;
For each face group obtained by the grouping means, type determining means for determining which of the predetermined shape types the face group belongs to based on the shape formed by the face group;
A cost database storing machining cost calculation rules according to the combination of shape type and roughness attribute;
For each surface group, a processing cost calculation rule corresponding to the combination of the shape type of the surface group determined by the type determination unit and the roughness attribute of each surface constituting the surface group is determined from the cost database. , An individual cost calculation means for calculating the processing cost of the surface group based on this rule,
The processing cost estimation apparatus characterized by including . The processing cost calculation rule of the cost database is further classified according to the direction of the surface group with respect to a preset main processing direction in addition to the shape type and roughness attribute of the surface group, and the individual cost calculation means processing cost estimation device according to claim 1, wherein by considering the orientation of face groups, characterized in that retrieving the machining cost calculation rule from the cost database. Furthermore it comprises a surface processing cost calculation means for calculating the total processing cost processing cost estimation device according to claim 1 or claim 2, wherein by total processing cost of each surface group. Means for setting a special machining attribute indicating the type of the special machining part in a part corresponding to a predetermined special machining part in the CAD model;
Means for extracting each special machining part from the CAD model;
Special processing cost database that registers processing cost calculation rules for each type of special processing part,
Means for calculating a machining cost calculation rule for each special machining site extracted from the CAD model from the special machining cost database, and calculating the total machining cost for the special machining site by summing them,
Means for obtaining the total machining cost of the entire CAD model by summing up the total machining cost relating to the special machining part and the machining cost obtained by the surface machining cost calculating means;
The processing cost estimation apparatus according to claim 3 , comprising: A processing unit price database in which processing unit prices are registered for each combination of processing type and roughness attribute,
Means for extracting a surface having a roughness attribute from CAD data representing a product;
Grouping the extracted surfaces based on the adjacent relationship to form a surface group, and for each surface group, a means for determining the processing type of the surface group based on the shape formed by the surface group;
For each surface group, a processing unit price corresponding to the combination of the processing type and roughness attribute of the surface group is obtained from the processing unit price database, and the surface group is determined from the processing unit cost and the area of the surface constituting the surface group. Means for calculating the processing cost of the entire processing target surface group by calculating the processing cost of each, and summing the processing costs of each surface group obtained,
A processing cost estimation device.

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