JPH07152820A - Mold designing method and mold designing support system - Google Patents

Abstract

PURPOSE:To improve the designing quality and efficiency in a method where a mold which is divided into plural parts on its parting surface is designed by deciding the shape of a mold combination face by a computer so as to secure a proper clearance between the mold combination faces counter to each other in a mold combined state. CONSTITUTION:An undivided mold material solid model, a product solid model and a reference parting surface model are inputted to a computer (S10-S30). A pair of mold combination faces where a proper clearance is secured in a mold combined state are produced in a surface model by the computer based on those input information (S60, S70). Then the intersecting line is calculated between a pair of mold combination faces and the mold material surface, and the mold material is divided into an upper die and a lower die based on the intersecting line so that an upper die solid model and a lower die solid model are obtained (S80-S100).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a design method and a design support system for a mold which is divided into a plurality of parts on a parting plane which is not a flat surface, and particularly, the mold matching surfaces interfere with each other during mold matching. In particular, the present invention relates to a technique for preventing an extra gap from occurring.

[0002]

2. Description of the Related Art In molding processes such as casting, forging, and injection molding, for example, a mold is used which is divided into a plurality of parts on a parting surface which is not a single plane.

The mold may be heated during its use. When using a mold that is scheduled to be heated in this way, the deformation of the mold does not cause interference between the mating surfaces that face each other or excessive clearance. It is important to perform die design and manufacturing.

Then, conventionally, the designer designs the shape of the mold matching surface independently for each divided portion of the mold based on the mold design drawing in which the product shape and the parting surface of the mold are drawn by the designer. Was.

[0005]

However, if a designer designs a die matching surface from a die design drawing, it takes time to design and it is difficult to maintain a constant design quality.

Further, since the designer separates the die-matching surfaces of the respective divided portions of the die from each other, in the die designing stage, the clearances that are generated between the die-matching surfaces facing each other at the time of die-matching can be accurately measured. Difficult to predict.
This is because the designer needs relatively complicated calculations to make the prediction. Therefore, in the conventional design method, it is necessary to perform mold correction many times after completion of the mold so that an appropriate clearance can be secured on the mold matching surface during mold matching, which is troublesome and time-consuming. Costly.

Against this background, the invention of claim 1 provides a method for designing the shapes of the mold matching surfaces by a computer while taking into consideration clearances generated between the mold matching surfaces. The objective was to improve and shorten the design time.

Further, the invention of claim 2 provides a system for supporting the work of designing the shapes of the mold matching surfaces while taking into consideration the clearances generated between them, thereby improving the quality of the mold design and designing time. The task was to reduce the time.

[0009]

In order to solve each of the problems, the invention of claim 1 is a method for designing a mold divided into a plurality of parts on a parting plane which is not a single plane, and , By inputting the parting plane, and by the computer, based on the input parting plane, the shape of the mold matching surface of each dividing part when the mold is divided into a plurality of parts by the parting plane, these dividing parts to each other It is determined that a predetermined clearance is generated between the mold matching surfaces facing each other when they are matched.

It should be noted that the term "a parting plane which is not one plane" is used herein except when the parting plane is composed of only one plane, such as a set of planes, a single curved surface, a set of curved surfaces, and a combination of planes and curved surfaces. It is meant to include the case of being composed of a set or the like.

The application of the "mold" here is, for example, casting, forging, injection molding or the like.

The term "designer inputs" means all the actions that result in information being supplied to the computer in accordance with the designer's intention. Not only when the information is directly supplied to the computer, for example, the designer inputs only the transfer command to the computer through the input means, and the computer responds to the command to read the information stored in advance from the external storage device. It also includes the case of importing into a computer.

The "clearance" is provided mainly for the deformation of the mold due to heat, but it may be provided for other purposes.

The "clearance" may be set directly by the designer, or may be automatically set by the computer when the designer inputs basic information.

As a mode for automatically setting, for example, a parting surface and a mold matching reference surface set in advance in the mold (for example, passing through each of a plurality of mold deviation preventing members provided in the mold and mold matching). And at least one mold matching center plane extending parallel to the direction, respectively, are input to the computer, and the distance between each of the points on the parting plane and the mold matching reference plane is calculated by the computer based on the parting plane and the mold matching reference plane. The clearance can be set so that the larger the distance, the larger the distance in the same direction as the direction of the distance. This is because one of the causes of interference between the mold matching surfaces is thermal expansion of the mold, and the amount of this thermal expansion has the property of increasing in accordance with the length of the member in which thermal expansion occurs.

In this embodiment, the amount of thermal expansion is affected not only by the length of the member in which thermal expansion occurs, but also by the temperature difference between the divided parts of the mold, so that the clearance is, for example, the temperature even if the distance is the same. The larger the difference, the larger the setting. Further, the amount of thermal expansion is affected not only by the length and temperature difference of the member in which thermal expansion occurs, but also by the material of the mold, that is, the coefficient of thermal expansion. It is desirable to set the larger the larger.

A second aspect of the present invention is a system for supporting the work of designing a mold to be divided into a plurality of parts on a parting plane which is not a plane, and (a) an input means capable of inputting the parting plane. (b) Based on the input parting surface, the shape of the mating surface of each divided part when the mold is divided into a plurality of parts by the parting surface, the shape of the mating surface facing each other when these divided parts are combined The processing means for deciding so that a preset clearance is generated between the two, and (c) display means for displaying the input result and the processing result on the screen.

[0018]

By designing each die-matching surface with a computer, design variations for each die-matching surface can be eliminated, and clearances that will occur between the die-matching surfaces facing each other in the die-matching state can be predicted. Each mold matching surface can be set easily and accurately. It is possible to design in consideration of the relationship between the mold matching surfaces facing each other.

Based on such knowledge, in the mold designing method according to the invention of claim 1, based on the parting plane input by the designer, the computer inserts a space between the mold matching planes facing each other in the mold matching state. The shape of the mold matching surface of each divided portion is determined so that a preset clearance is generated.

In the present invention, as the "method for obtaining a pair of mold matching surfaces that realizes clearance from the input parting plane", for example, as shown in FIG. 8, the parting plane input by the designer is used as a reference parting plane. Then, the reference parting surface is used as it is as one of the mold matching surfaces of each of the divided parts of the mold, and a surface for which clearance is secured in relation to the mold matching surface is created. As a method of using a mold matching surface, or as shown in FIG. 9, a parting plane input by a designer is used as a reference parting plane, and a pair of surfaces deviating from the reference parting plane in half directions of clearances in opposite directions to each other. It is possible to adopt a method of creating them and using them as a pair of mold matching surfaces.

Further, if the present invention is carried out in such a manner that the mold shape and the like are expressed using a solid model, it becomes easier to give a clearance to the mold matching surface, and further, the interference between the parts, It becomes easier to check undercuts, inclusion relations, etc. easily and accurately.

In the die design support system according to the second aspect of the present invention, based on the parting plane input by the input means, the clearance is preset by the processing means between the mating surfaces facing each other in the mating state. The shape of the mold matching surface of each divided portion is determined so that Further, the display unit displays the input result and the processing result on the screen.

[0023]

As is apparent from the above description, according to the inventions of the respective claims, since each mold matching surface is designed by the computer, the design quality is improved and the design time is shortened. Since each die mating surface is designed with due consideration of mutual relationships, the quality of die design is further improved, and the time and labor required for die modification can be easily omitted. It is possible to obtain an effect that the period until is easily shortened.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, each invention of claim 1 or 2 will be concretely described based on illustrated embodiments.

FIG. 2 shows the hardware configuration of a system that supports the design of a mold, which is an example of a molding die. This design support system is configured to include an input / output device, a processing device, and a display device. The input / output device is, for example, a keyboard 10, a mouse 12, a light pen (or a stylus pen of a digitizer) 14, a joystick 16, a dial (function selecting means) 1.
Input device 20 such as 8, hard copy 22, plotter 2
4 and other output devices 30, a magnetic disk device 32, a magnetic tape device 34, an auxiliary storage device 40 such as a CD-ROM device 36, and the like. The display device 50 is
Computer-based graphic controller 5
2, the CRT device 54 and the like are included.

By using this design support system, the designer can design the mold by operating the input device 20 while looking at the product shape and the like displayed on the screen of the CRT device 54. Further, the designed mold shape can be stored as data in the auxiliary storage device 40 and saved, or can be output on paper by the hard copy 22 or the plotter 24.

The design support system is based on the transmission line 6
It is connected to another system (not shown) via 0 and cooperates with each other to form a network.

The processing unit 70, as shown in FIG.
A computer 78 including a U 72, a ROM 74 and a RAM 76 is mainly configured. A program for design support is previously stored in the ROM 74, and the CPU
72 executes this design support program in accordance with a command from the designer. It should be noted that the design support program is stored in the auxiliary storage device 40 instead of the ROM 74, and is read out from the storage device 40 as needed and stored in the RAM 76.
The PU 72 may read and execute it.

This design support program includes a mold matching surface design program, and the contents of this program will be described below with reference to the flowchart of FIG.
In addition, the case where the parting plane shown in FIG. 4 is set for the product shown in FIG. 4 to design the mold shape will be described as an example with reference to FIGS.

First, conceptually, a parting surface set by a designer is expressed by a surface model, and a pair of mold matching surfaces that will have appropriate clearance in the mold matching state is created based on the surface model. Then, each is expressed by a surface model, and the mold material is divided into an upper mold and a lower mold by the pair of mold matching surfaces.

More specifically, first, in step S10 of FIG. 1 (hereinafter, simply referred to as S10; the same applies to other steps), the mold before division is based on the operation of the input device 20 by the designer. The shape of the mold material is input (see the front sectional view in S10 of FIG. 5). Solid model data expressing the shape of the die material is created. Next, in S20, the shape of the product to be manufactured by the mold is input (see the front sectional view in S20 of FIG. 5). Solid model data representing the product shape is created.

Then, in S30, the parting plane used when the mold material is divided into the upper die and the lower die is input as the reference parting plane (see the front sectional view in S30 of FIG. 5). While referring to the product shape displayed on the screen of the display device 50, the parting surface suitable for the product shape is input, and in this case, the parting surface is different from the former mold material shape and the product shape. Is represented by a surface model.

Then, in S40, the product solid model and the reference parting plane surface model are arranged in the mold material solid model based on the operation of the designer (see the front sectional view in S40 of FIG. 5). The data is not combined as a figure, but the data is stored so as to virtually overlap each other. Then, in S50, the part occupied by the product model in the mold material solid model, that is, the common part (product) with the product solid model is removed, and a hollow part is formed in the mold material solid model (FIG. 5). (See front sectional view of S50).

Subsequently, in S60, an appropriate clearance is set for each input point on the reference parting plane based on the operation by the designer (see the front sectional view in S60 of FIG. 6).

The designer can set the proper clearance for each point on the parting plane, but it can also be set automatically as described above.

Thereafter, in S70, the input reference parting surface is directly used as the first die mating surface, and the surface separated from the first die mating surface by an appropriate clearance is made the second die mating surface (FIG. 8 and FIG. 8). (Refer to the front sectional view in S70 of FIG. 6).

Regarding the second mold matching surface, when the cross section of the first mold matching surface is traced in a predetermined direction, the second mold matching surface is always on the predetermined side of the left side or the right side with respect to the mold matching surface. Determined to be located. as a result,
As shown in FIG. 8, the first and second mold matching surfaces are determined so that the distance between the inclined surfaces of the first mold matching surface is wider than the distance between the inclined surfaces of the second mold matching surface. .

Then, in S80, a plurality of lines (closed loops) at which the surface of the die material solid model having a hollow portion and the first and second mating surface surface models intersect each other are obtained (FIG. 6). S80
(See front sectional view and plan sectional view).

Subsequently, in S90, a plurality of surface segments (closed areas on a flat surface or a curved surface) defined by a plurality of closed intersecting lines obtained for each mold matching surface are operated on the basis of an operation by the designer. Of these, those included in the mold material are selected (see the front sectional view and the plan view in S90 of FIG. 6).

Then, in S100, the upper part of the upper part and the lower part when the mold material solid model having a hollow part is divided by the above-mentioned surface corresponding to the first mold mating surface is obtained as the upper mold solid model ( (See FIG. 7). Further, the lower part of the upper part and the lower part when the mold material solid model is divided by the above-mentioned surface corresponding to the second mold matching surface is obtained as the lower mold solid model (see FIG. 7). This completes the one-time execution of this program.

Whether the upper solid model and the lower solid model created as described above cause interference during die matching, whether some clearance occurs, and whether undercut occurs or not. It is possible to create the final upper solid model and the lower solid model respectively after checking the above.

Further, in the present embodiment, the shape of the cavity portion (the portion for molding the product shape) and the shape of the mold matching surface of the mold are required at the same time, but the respective acquisitions are different. Can be done in time.
For example, it is possible to first obtain the shape of the mating surface and then obtain the shape of the cavity portion.

Further, in the present embodiment, the proper clearance is set only on the inclined surface of the mold matching surface, but the proper clearance can be set on the non-inclined surface. .

As is clear from the above description, in the present embodiment, the design method according to the invention of claim 1 is implemented by the mold matching surface design program of FIG.
In addition, the input device 20 is one of the processing devices 70, which are shown in FIG.
30 constitutes an example of the "input means" in the invention of claim 2 in cooperation with the portion that executes 30, and the portion that executes S40 to 100 in the figure constitutes an example of the "processing means", and the display device 50 It constitutes an example of "display means".

Another embodiment is described in FIGS. The program of FIG. 10 differs from the mold matching surface design program of FIG. 1 only in the method of creating a pair of mold matching surfaces. That is, in the program of FIG. 1, as shown in FIG. 8, a pair of mold matching surfaces are directly obtained based on the reference parting plane input by the designer, whereas in the program of FIG. As shown in FIG. 11, the shape of the space occupied by the proper clearance to be generated is represented by a solid model, and a pair of mold matching surfaces is obtained by a set operation of the reference parting surface surface model and the clearance solid model.

The contents of the program shown in FIG. 10 will be described in detail below. As in the case of the program shown in FIG. 1, the case where the parting plane shown in FIG. 4 is set and the mold shape is designed for the product shown in FIG.
This will be described with reference to FIG. Further, detailed description of parts common to the program of FIG. 1 will be omitted, and only different parts will be described in detail.

First, S210 to 240 are executed in the same manner as in the program of FIG. 1 to create a mold material solid model, a product solid model, a reference parting plane surface model, and a product model in the mold material solid model. And the placement of the reference parting plane surface model.

Thereafter, in S250, as in S6 of FIG. 1, appropriate clearances are set for each point on the reference parting plane (see the front sectional view of S250 in FIG. 12). Subsequently, in S260, the shape of the space occupied by the appropriate clearance is created as a solid model (see the front sectional view in S260 of FIG. 12). Then, in S270, the common part of the product solid model and the clearance solid model is removed from the die material solid model, and a die material solid model having a hollow portion is created (see the front cross-sectional view in S270 of FIG. 12).

Then, in S280, the line of intersection between the surface of the mold material solid model having the hollow portion and the reference parting plane surface model is obtained (S2 in FIG. 12).
(See front sectional view and plan sectional view at 80). Then, in S290, the one included in the mold material is selected from the plurality of surface segments defined by the plurality of closed intersecting lines obtained based on the operation by the designer (the front cross-section in S290 of FIG. 13). See figure and plan).

Subsequently, in S300, the mold material solid model having a hollow portion is divided into an upper solid model and a lower solid model by the selected surface segment, and an upper solid model and a lower solid model are created respectively. (See the front sectional view in S300 of FIG. 13). This completes the one-time execution of this program.

As is apparent from the above description, in the present embodiment, the design method according to the invention of claim 1 is implemented by the mold matching surface design program of FIG. Further, the input device 20 constitutes an example of the "input means" in the invention of claim 2 in cooperation with a part of the processing device 70 which executes 210 to 230 of FIG.
The part that executes 0 to 290 constitutes an example of "processing means", and the display device 50 constitutes an example of "display means".

The invention of each claim has been specifically described above based on some embodiments shown in the drawings. However, in addition to these, based on the knowledge of those skilled in the art without departing from the scope of the claims. The invention of each claim can be embodied in various modified and improved modes.

[Brief description of drawings]

FIG. 1 is a flowchart showing a mold matching surface design program according to an embodiment common to the invention of each claim.

FIG. 2 is a diagram showing a hardware device configuration of a design support system for executing the pattern matching surface design program.

FIG. 3 is a diagram conceptually showing the structure of the processing apparatus in FIG.

FIG. 4 is a front cross-sectional view showing a mold and a cast product used for explaining the contents of the mold matching surface design program of FIG.

FIG. 5 is a diagram for explaining the execution contents of the mold matching surface design program of FIG. 1 in association with steps.

FIG. 6 is a diagram for explaining the execution contents of the mold matching surface design program of FIG. 1 in association with steps.

FIG. 7 is a diagram for explaining the execution contents of the mold matching surface design program of FIG. 1 in association with steps.

FIG. 8 is a cross-sectional view for explaining an example of a method of creating a pair of mold matching surfaces that realizes proper clearance from a reference parting surface.

FIG. 9 is a cross-sectional view for explaining another example of a method of creating a pair of mold matching surfaces that realizes proper clearance from a reference parting surface.

FIG. 10 is a flowchart showing a mold matching surface design program in another embodiment.

11 is a cross-sectional view for explaining an example of a method of creating a pair of mold matching surfaces that realizes proper clearance from a reference parting surface in the mold matching surface design program of FIG.

FIG. 12 is a diagram for explaining the execution contents of the mold matching surface design program of FIG. 10 in association with steps.

FIG. 13 is a diagram for explaining the execution contents of the mold matching surface design program of FIG. 10 in association with steps.

[Explanation of symbols]

 20 input device 30 output device 40 auxiliary storage device 50 display device 70 processing device

Claims (2)

[Claims] 1. A method of designing a mold to be divided into a plurality of parts on a parting plane which is not a single plane, wherein the parting plane is input to a computer, and the computer calculates the parting plane based on the input parting plane. When the mold is divided into a plurality of parts on the parting surface, the shape of the mold matching surface of each divided part is adjusted so that when the divided parts are combined with each other, a preset clearance is generated between the opposed mold matching surfaces. A method for designing a die using a computer, characterized in that 2. A system for supporting the work of designing a mold to be divided into a plurality of parts on a parting plane which is not a single plane, wherein the input means is capable of inputting the parting plane, and based on the input parting plane, When the mold is divided into a plurality of parts along the parting surface, the shapes of the mold matching surfaces of the respective divided parts are matched with each other, and a preset clearance is generated between the mold matching surfaces facing each other. And a display means for displaying an input result and a processing result on a screen.