JP2009184204A - Method of designing mold, system thereof, program thereof, and storage medium readable with computer storing program thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of designing a mold, a system, a program and a storage medium can easily and appropriately determining a disposition of an extruded core provided on the mold. <P>SOLUTION: An angle for product extracting of a plurality of cavity element surfaces composing a cavity surface formed on the mold is calculated, the cavity element surface where a mold release resistance becomes larger than a predetermined threshold from the relation between the angle for product extracting and the release resistance is extracted. The abutted surface mutually adjacent plurality of cavity element surfaces of the extracted cavity element surfaces are extracted is set as a cavity element surface, and the disposition of an extruded core facing the cavity element composite surfaces is determined from the center of gravity of a projected shape in the product extracting direction of the cavity element composite surface. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a technique for designing a mold. More specifically, the present invention relates to a technique for determining the arrangement of an extruded core that peels a product from a mold.

Conventionally, as a method of designing a mold for molding a product, a parting model is generated by correcting the three-dimensional shape (scaling model) of the product based on the shrinkage rate or expansion rate of the raw material of the product. Based on the process and parting model, the moving mold moving direction (product removal direction), parting line, cavity surface and parting surface (mating surface between movable mold and fixed mold) shape There are known methods comprising the step of determining.
For example, as described in Patent Document 1.

Conventionally, as a method of designing a mold for molding a product, in addition to the above steps, a gas is externally supplied from a supply path (gate) for supplying a molten raw material to the mold cavity and the mold cavity. The process of determining the arrangement of the exhaust path (gas vent) for discharging to the mold, the process of determining the arrangement of the flow path of the cooling water for cooling the mold, the extrusion pin or extrusion for extracting (peeling) the product from the mold A method including a step of determining the arrangement of cores is known.
For example, as described in Patent Document 2.

For example, the outer shape is created first, such as an automobile bumper, and then the inner shape is created so that the outer shape has a substantially constant thickness. ) When designing a mold that molds a product to be created, calculate the centroid position of multiple element surfaces (surface data) that make up the outer shape of the product, and use the calculated centroid position as the starting point. A normal vector perpendicular to the center of gravity is calculated, an offset direction indicating vector from the center of gravity position to a preset offset indicating point is calculated, and an element plane is determined based on an angle formed by the normal vector and the offset direction indicating vector. A mold design system is known that creates a shape inside a product by offsetting it by a predetermined amount in the direction of the normal vector or in the opposite direction of the normal vector.
For example, as described in Patent Document 3.

Regarding the mold design, calculate the projected area of the product and the depth of the mold in the product removal direction based on the three-dimensional shape of the product (scaling model) and the product removal direction (moving direction of the movable mold), There is also known a system for calculating the cost of a product molded by a mold based on the calculated projected area of the product in the product removal direction and the depth of the mold.
For example, as described in Patent Document 4.

Extrusion pins or cores for extracting (peeling) the product from the mold reduce the cycle time of the product by preventing the occurrence of incidental work associated with the product adhering to the mold. It is an important part in improving mold productivity.
In particular, the extruded core does not only have the function of extracting (peeling) the product from the mold like an extruded pin, but also the tip part is flush with the cavity surface of the mold and part of the surface shape of the product. It also has a function of holding the product supported in a certain posture until it is carried or the product peeled from the mold is delivered to the next work process.
Therefore, it is important to properly set the arrangement and shape of the extrusion core provided in the mold in the mold design.

  As a technique for determining the arrangement and shape of the extrusion core (or extrusion pin) in the mold design, a mold design support device described in Patent Document 5 and a mold design method described in Patent Document 6 are known. .

The mold design support apparatus described in Patent Document 5 is a mold release resistance shape on the cavity surface of the mold (at the contact portion between the cavity surface of the mold and the surface of the product when the product is peeled off from the mold) Depending on whether or not there is a shape of a portion on which a large stress acts), it is selected whether to provide the extrusion core, the internal extrusion core or the slide core in the mold.
However, the mold design support apparatus described in Patent Document 5 does not disclose a specific method for determining the position where the selected extruded core is disposed and the width of the extruded core.

The mold design method described in Patent Document 6 is based on whether the load applied to the push pin when the product is extracted from the mold is equal to or less than the yield stress of the material constituting the product. To evaluate.
However, in the mold design method described in Patent Document 6, when the product is extracted from the mold with the shape and arrangement of the push pin set and input by the operator, the load applied to the push pin that is set and input is applied to the product. Since it is determined whether or not it is equal to or less than the yield stress of the constituent material, the shape and arrangement of the push pin to be set and input are left to the discretion of the operator.
Therefore, the shape and arrangement of the push pin that is set and input are substantially determined as a result of the trial and error of the operator, and may vary depending on the operator (not uniquely determined according to a certain rule). Nevertheless, Patent Document 6 does not disclose a specific method for determining the shape and arrangement of the push pin.
Japanese Patent No. 3629439 JP 2006-155629 A JP 2000-331046 A JP 2002-351928 A JP 2006-79205 A JP 2001-71064 A

  The present invention has been made in view of the above situation, and a mold design method, a mold design system, and a mold design program capable of easily and appropriately determining the arrangement of an extrusion core provided in a mold. And a computer-readable storage medium storing a mold design program.

  The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described.

That is, in claim 1,
A mold design method for designing a mold for molding a product,
A product extraction angle calculation step of calculating a product extraction angle, which is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed in the mold and the product extraction direction, for each cavity element surface;
Cavity element surface extraction step for extracting, among the plurality of cavity element surfaces, the one having the release resistance larger than a predetermined threshold, based on the relationship between the product extraction angle and the mold release resistance obtained in advance.
A cavity element composite surface setting step of setting a combination of a plurality of adjacent cavity element surfaces among the cavity element surfaces extracted in the cavity element surface extraction step as a cavity element composite surface;
An extruded core arrangement determining step for determining the arrangement of the extruded core facing the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface;
It comprises.

In claim 2,
In the extruded core arrangement determining step,
The extruded core is disposed at a position where the center of gravity of the projected shape in the product extraction direction of the cavity element composite surface and the center of gravity of the projected shape in the product extraction direction of the extruded core coincide with each other when viewed from the product extraction direction. is there.

In claim 3,
In the extruded core arrangement determining step,
Calculating the projected area of the extruded core in the product removal direction based on the projected shape area of the cavity element composite surface in the product removal direction and the projected shape area of the cavity element composite surface in the direction perpendicular to the product removal direction It is.

In claim 4,
Extrusion core for determining whether or not the extruded core whose arrangement is determined in the extruded core arrangement determining step can hold the state where the product is supported by the extruded core when the product is peeled from the mold. An arrangement determining step is provided.

In claim 5,
In the extruded core arrangement determining step,
Based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface, an effective extrusion range is set in which the extrusion force by the extrusion core reaches the product,
When the outline of the effective range of extrusion seen from the product pulling direction intersects the parting line of the mold, it is determined that the product can be held in the state supported by the extruded core,
When the outline of the effective range of extrusion does not intersect the parting line of the mold when viewed from the product pulling direction, it is determined that it is impossible to keep the product supported by the extruded core. Is.

In claim 6,
In the extruded core arrangement determining step,
When it is determined that it is impossible to maintain the state where the product is supported by the extruded core, a product supporting core facing the position different from the cavity element composite surface in the product is set.

In claim 7,
A mold design system for designing a mold for molding a product,
A product extraction angle calculation unit for calculating a product extraction angle, which is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed in the mold and the product extraction direction, for each cavity element surface;
Based on the relationship between the product extraction angle determined in advance and the mold release resistance, among the plurality of cavity element surfaces, a cavity element surface extraction unit that extracts the mold release resistance greater than a predetermined threshold;
Among the cavity element surfaces extracted by the cavity element surface extraction unit, a cavity element composite surface setting unit that sets a combination of a plurality of adjacent cavity element surfaces as a cavity element composite surface;
An extruded core arrangement determining unit that determines the arrangement of the extruded core facing the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface;
It comprises.

In claim 8,
The extruded core arrangement determining unit is
The extruded core is disposed at a position where the center of gravity of the projected shape in the product extraction direction of the cavity element composite surface and the center of gravity of the projected shape in the product extraction direction of the extruded core coincide with each other when viewed from the product extraction direction. is there.

In claim 9,
The extruded core arrangement determining unit is
Calculating the projected area of the extruded core in the product removal direction based on the projected shape area of the cavity element composite surface in the product removal direction and the projected shape area of the cavity element composite surface in the direction perpendicular to the product removal direction It is.

In claim 10,
Extrusion core for determining whether or not the extruded core whose arrangement has been determined by the extruded core arrangement determining unit can maintain the state in which the product is supported by the extruded core when the product is peeled from the mold. An arrangement determination unit is provided.

In claim 11,
The extruded core arrangement determining unit
Based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface, an effective extrusion range is set in which the extrusion force by the extrusion core reaches the product,
When the outline of the effective range of extrusion seen from the product pulling direction intersects the parting line of the mold, it is determined that the product can be held in the state supported by the extruded core,
When the outline of the effective range of extrusion does not intersect the parting line of the mold when viewed from the product pulling direction, it is determined that it is impossible to keep the product supported by the extruded core. Is.

In claim 12,
The extruded core arrangement determining unit
When it is determined that it is impossible to maintain the state where the product is supported by the extruded core, a product supporting core facing the position different from the cavity element composite surface in the product is set.

In claim 13,
A mold design program for designing a mold for molding a product,
On the computer,
A product extraction angle calculation function for calculating a product extraction angle, which is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed in the mold and the product extraction direction, for each cavity element surface;
Cavity element surface extraction function for extracting, from among the plurality of cavity element surfaces, the one having the release resistance larger than a predetermined threshold, based on the relationship between the product extraction angle and the mold release resistance obtained in advance.
A cavity element composite surface setting function for setting a cavity element composite surface as a combination of a plurality of adjacent cavity element surfaces among the cavity element surfaces extracted by the cavity element surface extraction function;
An extruded core arrangement determining function for determining the arrangement of the extruded core facing the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface;
It is for realizing.

In claim 14,
The extruded core arrangement determining function is
The extruded core is disposed at a position where the center of gravity of the projected shape in the product extraction direction of the cavity element composite surface and the center of gravity of the projected shape in the product extraction direction of the extruded core coincide with each other when viewed from the product extraction direction. is there.

In claim 15,
The extruded core arrangement determining function is
Calculating the projected area of the extruded core in the product removal direction based on the projected shape area of the cavity element composite surface in the product removal direction and the projected shape area of the cavity element composite surface in the direction perpendicular to the product removal direction It is.

In claim 16,
Extrusion core for determining whether or not the extruded core whose arrangement is determined by the extruded core arrangement determining function can hold the state in which the product is supported by the extruded core when the product is peeled from the mold. This is for realizing the arrangement determination function.

In claim 17,
The extruded core arrangement determination function is
Based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface, an effective extrusion range is set in which the extrusion force by the extrusion core reaches the product,
When the outline of the effective range of extrusion seen from the product pulling direction intersects the parting line of the mold, it is determined that the product can be held in the state supported by the extruded core,
When the outline of the effective range of extrusion does not intersect the parting line of the mold when viewed from the product pulling direction, it is determined that it is impossible to keep the product supported by the extruded core. Is.

In claim 18,
The extruded core arrangement determination function is
When it is determined that it is impossible to maintain the state where the product is supported by the extruded core, a product supporting core facing the position different from the cavity element composite surface in the product is set.

In claim 19,
A computer-readable storage medium storing a mold design program for designing a mold for molding a product,
On the computer,
A product extraction angle calculation function for calculating a product extraction angle, which is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed in the mold and the product extraction direction, for each cavity element surface;
Cavity element surface extraction function for extracting, from among the plurality of cavity element surfaces, the one having the release resistance larger than a predetermined threshold, based on the relationship between the product extraction angle and the mold release resistance obtained in advance.
A cavity element composite surface setting function for setting a cavity element composite surface as a combination of a plurality of adjacent cavity element surfaces among the cavity element surfaces extracted by the cavity element surface extraction function;
An extruded core arrangement determining function for determining the arrangement of the extruded core facing the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface;
It is for realizing.

In claim 20,
The extruded core arrangement determining function is
The extruded core is disposed at a position where the center of gravity of the projected shape in the product extraction direction of the cavity element composite surface and the center of gravity of the projected shape in the product extraction direction of the extruded core coincide with each other when viewed from the product extraction direction. is there.

In claim 21,
The extruded core arrangement determining function is
Calculating the projected area of the extruded core in the product removal direction based on the projected shape area of the cavity element composite surface in the product removal direction and the projected shape area of the cavity element composite surface in the direction perpendicular to the product removal direction It is.

In claim 22,
Extrusion core for determining whether or not the extruded core whose arrangement is determined by the extruded core arrangement determining function can hold the state in which the product is supported by the extruded core when the product is peeled from the mold. This is for realizing the arrangement determination function.

In claim 23,
The extruded core arrangement determination function is
Based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface, an effective extrusion range is set in which the extrusion force by the extrusion core reaches the product,
When the outline of the effective range of extrusion seen from the product pulling direction intersects the parting line of the mold, it is determined that the product can be held in the state supported by the extruded core,
When the outline of the effective range of extrusion does not intersect the parting line of the mold when viewed from the product pulling direction, it is determined that it is impossible to keep the product supported by the extruded core. Is.

In claim 24,
The extruded core arrangement determination function is
When it is determined that it is impossible to maintain the state where the product is supported by the extruded core, a product supporting core facing the position different from the cavity element composite surface in the product is set.

  The present invention has an effect that the arrangement of the extrusion core provided in the mold can be easily and appropriately determined.

  Hereinafter, a schematic configuration of a CAD (Computer Aided Design) system 101 that is a first embodiment of a mold design system according to the present invention will be described with reference to FIG.

As shown in FIG. 1, the CAD system 101 is for designing a mold for molding a bumper for a car as a product, and includes a CAD terminal device 110, a storage device 120, and a control device 130.
The CAD terminal device 110 and the storage device 120, the CAD terminal device 110 and the control device 130, and the storage device 120 and the control device 130 are connected to each other, and can transmit and receive data to and from each other. It is.

The CAD terminal device 110 is a device that inputs a numerical value or an instruction to the control device 130 and displays a calculation result by the control device 130 (for example, an image representing an arrangement of an extrusion core provided in a mold).
The CAD terminal device 110 may be a dedicated product, or may be realized by using a general-purpose product (including a keyboard, a mouse, and a display) such as a commercially available personal computer or workstation.

The storage device 120 stores various data and outputs data stored in the CAD terminal device 110 or the control device 130.
The storage device 120 may be a dedicated product, or may be realized using a commercially available HDD (Hard Disc Drive), CD-ROM, DVD-ROM, or the like.

  In the present embodiment, the storage device 120 has a three-dimensional shape (scaling model), a parting model, a cavity shape (cavity surface shape), a parting surface shape, and a parting line shape of an automotive bumper that is a product in advance. Such information is stored.

  The “parting model” is obtained by correcting the three-dimensional shape of the product based on the shrinkage rate (or the expansion rate) of the raw material of the product. FIG. 3 shows an embodiment of an automotive bumper parting model.

“Cavity” is formed inside the mold and melts the raw material of the product molded by the mold, or the raw material of the product molded by the mold is made into powder (powder or granule) A space where things are supplied.
“Cavity surface” refers to the surface of a mold that faces the cavity.
The shape of the cavity (the shape of the cavity surface) usually matches the shape of the parting model.

  The “parting surface” refers to a mating surface of the molds, that is, a surface where the fixed mold and the movable mold come into contact with each other when the mold is closed in the mold having the fixed mold and the movable mold.

A “parting line” refers to a line that forms a boundary between a parting surface and a cavity surface in a mold having a fixed mold and a movable mold.
The parting line is usually an endless ring drawn without crossing along the surface of the parting model.

  “Product removal direction” refers to the direction in which the product is removed from the mold. The product removal direction usually coincides with the moving direction (opening / closing direction) of the movable mold relative to the fixed mold in the mold having the fixed mold and the movable mold. In general, the “product removal direction” and the direction in which the extruded core moves relative to the mold when the product is peeled from the mold (extrusion direction) coincide with each other.

  In the present invention, the information related to the product scaling model, parting model, cavity shape, parting surface shape, and parting line shape widely includes information created by known methods.

The control device 130 is a device that performs a predetermined calculation according to a stored program based on data stored in the storage device 120 and numerical values and instructions input by the CAD terminal device 110.
The control device 130 is essentially connected to a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read-Only Memory), an HDD, or the like via a bus. Alternatively, a configuration realized by a one-chip LSI (Large Scale Integration) may be used.
The control device 130 may be a dedicated product, or may be realized using a commercially available general-purpose product (including a keyboard, a mouse, an optical drive, and a display) such as a personal computer or a workstation.

When an operator (in this embodiment, a mold designer) inputs a numerical value or an instruction by operating the CAD terminal device 110, data related to the numerical value or the instruction is transmitted to the storage device 120 and the control device 130. .
The storage device 120 appropriately stores data (numerical values and instructions input by the operator) transmitted from the CAD terminal device 110.
Based on the data (numerical values and instructions input by the operator) transmitted from the CAD terminal device 110 and the data stored in the storage device 120, the control device 130 performs predetermined processing according to a program stored in advance in the control device 130. While performing the calculation, the calculation result is transmitted to the CAD terminal device 110 and the storage device 120.
The CAD terminal device 110 displays the calculation result transmitted from the control device 130. The storage device 120 stores the calculation result transmitted from the control device 130 as appropriate.

Below, the schematic structure of the CAD system 102 which is 2nd embodiment of the metal mold | die design system based on this invention is demonstrated using FIG.
As shown in FIG. 2, the CAD system 102 includes a plurality of CAD terminal devices 110, 110..., A storage device 120, and a control device 130.
The CAD terminal device 110 and the storage device 120, the CAD terminal device 110 and the control device 130, and the storage device 120 and the control device 130 are connected by the network 140, respectively, and can transmit and receive data to and from each other. Is possible.
Specific examples of the network 140 include the Internet and an intranet.

  The CAD system 102 includes a plurality of CAD terminal devices 110, 110,..., And a plurality of workers simultaneously operate different CAD terminal devices 110 to input numerical values or instructions to the control device 130 (molds). 1 is different from the CAD system 101 shown in FIG. 1 in that the calculation result by the control device 130 (for example, an image showing the arrangement of the extrusion core provided in the mold) can be displayed. The other points are basically the same as those of the CAD system 101.

  The CAD system 101 shown in FIG. 1 and the CAD system 102 shown in FIG. 2 are each composed of a CAD terminal device 110, a storage device 120, and a control device 130, which are separated into one personal computer or workstation. Etc. may be realized.

The CAD system 101 and the CAD system 102 according to the present embodiment are designed to design a mold for molding a resin automobile bumper (particularly, a bumper attached to the front of the automobile) as a product. However, the present invention is limited to this. Is not to be done.
That is, the present invention can be used for designing a mold for forming a product having a predetermined shape by filling a molten material (for example, a resin material or a metal material) and solidifying the material, or a granular material (for example, a powdery material). It can be widely applied to the use of designing a mold for forming a product having a predetermined shape by filling (pressing (or heating)) a metal material, resin material or ceramic).

Below, the detail of the control apparatus 130 is demonstrated using FIGS. 1-7.
As shown in FIG. 1, the control device 130 functionally includes a CAD function processing unit 131, a product extraction angle calculation unit 132, a cavity element surface extraction unit 133, a cavity element composite surface setting unit 134, an extruded core arrangement determination unit 135, and An extruded core arrangement determining unit 136 is provided.

The CAD function processing unit 131 has a drawing function related to a two-dimensional shape or a three-dimensional shape, and an interface function between the CAD terminal device 110 and the control device 130.
Substantially, the control device 130 performs a predetermined calculation according to CAD software stored in the control device 130, thereby fulfilling the function as the CAD function processing unit 131.
The CAD software may be developed exclusively for the software or may be commercially available.

The product extraction angle calculation unit 132 is an embodiment of the product extraction angle calculation unit according to the present invention, and is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed in the mold and the product extraction direction. The “product extraction angle” is calculated for each cavity element surface.
Substantially, the control device 130 performs a predetermined calculation in accordance with a mold design program stored in the control device 130, thereby functioning as a product extraction angle calculation unit 132.

  The “plurality of cavity element surfaces” refers to “an assembly of minute planes constituting the cavity surface”. For example, in the case of a mold for molding a bumper of an automobile as a product, the cavity surface formed on the mold is configured as an assembly of hundreds to thousands of cavity element surfaces.

The product extraction angle calculation unit 132 acquires information related to the shape of the cavity surface of the bumper for the automobile stored in the storage device 120, and thus information related to a plurality of cavity element surfaces constituting the cavity surface. Information on the product removal direction of the automobile bumper stored in 120 is acquired, and an angle formed by each cavity element surface and the product removal direction is calculated based on the information.
The storage device 120 appropriately stores information related to the “product extraction angle for each cavity element surface” calculated by the product extraction angle calculation unit 132.

The cavity element surface extraction unit 133 is an embodiment of the cavity element surface extraction unit according to the present invention. The cavity element surface extraction unit 133 determines the cavity surface of the mold based on the “relation between the product drawing angle and the mold release resistance” obtained in advance. Among the plurality of cavity element surfaces to be configured, those having a mold release resistance larger than a predetermined threshold are extracted.
Substantially, the control device 130 performs a predetermined calculation according to a mold design program stored in the control device 130, thereby functioning as the cavity element surface extraction unit 133.

“Release resistance” refers to the resistance force that acts between the mold and the product when the molded product is released (peeled) from the mold.
The mold release resistance is usually given as a stress per unit area converted to a plane perpendicular to the product removal direction.
The mold release resistance varies depending on the cavity surface (or the surface of the product fixed to the mold), more specifically, the angle formed by the cavity element surface and the product removal direction.

As shown in FIG. 4, generally, the smaller the product removal angle θ (the closer the product removal direction is parallel to the cavity surface), the greater the mold release resistance.
For example, in FIG. 4, when it is desired to extract a cavity element surface having a release resistance larger than the threshold value F1, a cavity element surface having a product removal angle smaller than the angle θ1 may be extracted.

The cavity element surface extraction unit 133 acquires information related to the product extraction angle for each of the plurality of cavity element surfaces constituting the cavity surface of the mold stored in the storage device 120.
The cavity element surface extraction unit 133 is a bumper for automobiles that is a product among the plurality of cavity element surfaces constituting the cavity surface of the mold, based on the acquired information about the product extraction angle for each of the plurality of cavity element surfaces. As for the cavity element surface corresponding to the vicinity of the reinforcing rib formed on the inner surface, the cavity element surface having an angle of 2 ° or less with the product removal direction is extracted.
In addition, the cavity element surface extraction unit 133 has an angle of 5 ° with respect to the product removal direction for the cavity element surfaces other than the cavity element surfaces corresponding to the vicinity of the reinforcing rib formed on the inner surface of the automobile bumper. Extract the cavity element surfaces as follows.
The storage device 120 appropriately stores information related to the cavity element surface extracted by the cavity element surface extraction unit 133.

In the present embodiment, the product extraction angle value (and thus the release resistance threshold value) used when extracting the cavity element surface is set to a plurality according to the relationship with the part of the automotive bumper that is the product. The present invention is not limited to this.
That is, the number of threshold values for the release resistance can be appropriately selected according to the properties of the product (the shape of the product, the surface roughness of the product, the mechanical properties of the raw material of the product, etc.).

The cavity element composite surface setting unit 134 is an embodiment of the cavity element composite surface setting unit according to the present invention. Among the cavity element surfaces extracted by the cavity element surface extraction unit 133, a plurality of adjacent cavity element surfaces are provided. Is set as a “cavity element composite surface”.
Substantially, the control device 130 performs a predetermined calculation according to the mold design program stored in the control device 130, thereby functioning as the cavity element composite surface setting unit 134.

For example, as shown in FIG. 5, the cavity element composite surface setting unit 134 includes the cavity element surfaces 16, 26, 26, which are adjacent to each other among the cavity element surfaces 11, 12, 13... When 17 · 20 · 21 is the cavity element surface extracted by the cavity element surface extraction unit 133, the cavity element surfaces 16 · 17 · 20 · 21 are combined (indicated by a thick solid line in FIG. 5). ) Is set as the cavity element composite surface 30.
The storage device 120 appropriately stores information related to the cavity element composite surface set by the cavity element composite surface setting unit 134.

The extruded core arrangement determining unit 135 is an embodiment of the extruded core arrangement determining unit according to the present invention, and the extruded core that faces the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface Is determined.
Substantially, the control device 130 performs a predetermined calculation in accordance with a mold design program stored in the control device 130, thereby fulfilling a function as the extruded core arrangement determining unit 135.

  The extruded core arrangement determining unit 135 includes a compound surface projection shape creating unit 135a, a compound surface projection shape centroid position calculating unit 135b, a compound surface projection area calculating unit 135c, and an arrangement determining unit 135d.

The composite surface projection shape creation unit 135a includes the “projection shape of the cavity element composite surface set by the cavity element composite surface setting unit 134 in the product removal direction” and the “projection shape of the cavity element composite surface set by the cavity element composite surface setting unit 134”. The projection shape in a direction perpendicular to the product removal direction is created.
For example, as shown in FIG. 6, the composite surface projection shape creation unit 135a uses the cavity element composite surface 30 as a figure projected onto the projection surface 41 that is a surface perpendicular to the product removal direction (L direction). A projection shape 31 in the product removal direction is created.
Further, the composite surface projection shape creation unit 135a projects the cavity element composite surface 30 onto a projection surface 42 which is a predetermined surface perpendicular to the vertical direction (H direction) of the automobile bumper as a product among the surfaces parallel to the product removal direction. As the figure, a projection shape 32 in the direction perpendicular to the product removal direction of the cavity element composite surface 30 is created.
The storage device 120 has information relating to the “projection shape of the cavity element composite surface in the product removal direction” and the “projection shape of the cavity element composite surface in the direction perpendicular to the product removal direction” created by the composite surface projection shape creation unit 135a. Is stored as appropriate.

The composite surface projection shape centroid position calculation unit 135b calculates the centroid position of the projection shape in the product removal direction of the cavity element composite surface created by the composite surface projection shape creation unit 135a.
For example, as shown in FIG. 6, the composite surface projection shape gravity center position calculation unit 135b determines the position of the gravity center 31a of the projection shape 31 in the product removal direction of the cavity element composite surface 30 (the gravity center position of the projection shape 31). Calculation is performed in the form of coordinates (h1, w1) on the projection plane 40 which is a plane perpendicular to the drawing direction.
The storage device 120 appropriately stores information related to “the centroid position of the projection shape in the product removal direction of the cavity element composite surface” calculated by the composite surface projection shape centroid position calculation unit 135b.

The composite surface projection area calculation unit 135c is created by the composite surface projection shape creation unit 135a as “projection shape of the cavity element composite surface in the product removal direction” and “projection shape of the cavity element composite surface in the direction perpendicular to the product removal direction”. Based on the above, the “area of the projected shape in the product removal direction of the cavity element composite surface (projected area)” and “the area of the projected shape in the direction perpendicular to the product removal direction of the cavity element composite surface (projected area)” are calculated. Is.
For example, as shown in FIG. 6, the composite surface projected area calculation unit 135c projects the projection shape 31 in the product removal direction of the cavity element composite surface 30 (in the present embodiment, the L direction corresponding to the front-rear direction of the bumper for automobiles). While calculating the area S1, the projection area S2 of the projection shape 32 in a predetermined direction perpendicular to the product removal direction of the cavity element composite surface 30 (in this embodiment, the H direction corresponding to the vertical direction of the bumper for automobiles) calculate.
The storage device 120 calculates the “area of the projected shape in the product removal direction of the cavity element composite surface (projection area)” calculated by the composite surface projected area calculation unit 135c and the “vertical direction perpendicular to the product removal direction of the cavity element composite surface”. Information related to “area of projected shape in direction (projected area)” is stored as appropriate.

  The arrangement determining unit 135d calculates “the center of gravity position of the projection shape in the product removal direction of the cavity element composite surface” calculated by the composite surface projection shape gravity center position calculation unit 135b, and “the cavity element calculated by the composite surface projection area calculation unit 135c”. Extrusion provided on the mold based on the “projected area of the composite surface in the product removal direction” and the “projected area of the cavity element composite surface in a predetermined direction perpendicular to the product removal direction” calculated by the composite surface projected area calculation unit 135c The shape and arrangement of the core are determined.

In the present embodiment, the length of the extruded core in the product removal direction (L direction) and the length of a predetermined direction (H direction) perpendicular to the product extraction direction of the extruded core are preset and stored in the storage device 120. Is done.
The arrangement determining unit 135d stores the length of the extruded core in the product extraction direction (L direction) stored in the storage device 120, the length in a predetermined direction (H direction) perpendicular to the product extraction direction of the extruded core, The projected area in the product removal direction of the composite surface and the “projected area in a predetermined direction perpendicular to the product removal direction of the cavity element composite surface” are displayed on the CAD terminal device 110.
Based on the “projected area of the cavity element composite surface in the product removal direction” and the “projection area of the cavity element composite surface in the direction perpendicular to the product removal direction” displayed on the CAD terminal device 110, the “mold” The length in the direction perpendicular to both the product pulling direction and the predetermined direction perpendicular to the product pulling direction of the extruded core provided in is calculated.
The operator inputs the calculated “length of the extruded core provided in the mold in the direction perpendicular to both the product removal direction and a predetermined direction perpendicular to the product removal direction” to the CAD terminal device 110.
The arrangement determining unit 135d uses the value input to the CAD terminal device 110 as “the length in the direction perpendicular to both the product withdrawal direction of the extruded core provided in the mold and the predetermined direction perpendicular to the product withdrawal direction”. Determine as.
The storage device 120 receives information related to “the length in the direction perpendicular to both the product removal direction of the extruded core provided in the mold and the predetermined direction perpendicular to the product removal direction” input by the CAD terminal device 110. Remember.

In this way, the arrangement determining unit 135d determines the shape of the extruded core provided in the mold, that is, “length in the product removal direction (length in the L direction)”, “length in a predetermined direction perpendicular to the product removal direction. “Length (length in the H direction)” and “length in the direction perpendicular to both the product removal direction and a predetermined direction perpendicular to the product removal direction (length in the W direction)” are determined.
The arrangement determining unit 135d calculates the gravity center position of the projection shape (rectangular or square in the case of the present embodiment) in the product removal direction of the extrusion core provided in the mold, and calculates the calculated “gravity position of the extrusion core” and “ The arrangement of the extruded core is determined at a position where the “center of gravity of the projected shape of the cavity element composite surface” coincides when viewed from the product removal direction.
The storage device 120 stores information related to the shape and arrangement of the extruded core determined by the arrangement determining unit 135d.

In the present embodiment, the length in the L direction and the H direction among the shapes of the extruded cores are set to predetermined values (predetermined values), and the length in the W direction is set to “projection in the product removal direction of the cavity element composite surface”. Although it is configured to calculate based on “area” and “projected area in the direction perpendicular to the product removal direction of the cavity element composite surface”, the present invention is not limited to this, and other methods in the product removal direction of the extruded core It is good also as a structure which calculates a projection area.
As an example of another configuration, (a) the shape of the extruded core (projected shape in the product pulling direction) viewed from the product pulling direction is previously determined as a circle, and “projection area of the cavity element composite surface in the product pulling direction” And a configuration in which the circular area (diameter) is calculated based on the “projected area in the direction perpendicular to the product removal direction of the cavity element composite surface”, or (b) The relational expression of “projection area in the direction”, “projection area in the direction perpendicular to the product removal direction of the cavity element composite surface” and “projection area of the extruded core in the product removal direction” is stored, and “cavity” is stored in the relational expression. Calculate the projected area of the element composite surface in the product removal direction and the projected area of the cavity element composite surface in the direction perpendicular to the product removal direction. Arrangement for, and the like.
In addition, the shape of the product (in the case of this embodiment, the bumper for an automobile is generally long in the width direction (W direction) of the automobile, and the shape of the cavity element composite surface viewed from the product pulling direction also tends to be long in the W direction. The projected area of the extruded core in the product removal direction may be calculated in consideration of factors such as the mechanical properties (yield stress, longitudinal elastic modulus, transverse elastic modulus, etc.) of the raw material of the product.

In this embodiment, the length of the extruded core stored in the storage device 120 in the product removal direction (L direction), the length in the predetermined direction (H direction) perpendicular to the product extraction direction of the extruded core, The projected area in the product removal direction of the composite surface and the “projected area in a predetermined direction perpendicular to the product removal direction of the cavity element composite surface” are displayed on the CAD terminal device 110, and the operator pushes out the core based on the display result. However, the present invention is not limited to this, and the shape of the extruded core may be determined by another configuration.
For example, a configuration may be adopted in which data on the shape of the extruded core of an automobile bumper created in the past is stored in advance in a storage device, and the shape of the extruded core is determined by an operator referring to (comparing) the data. The relationship between the projected area of the cavity element composite surface in the product removal direction and the projected area of the cavity element composite surface in the direction perpendicular to the product removal direction and the projected area of the extruded core in the product removal direction May be stored in advance, and based on this, the extruded core arrangement determining unit may determine the “projected shape of the extruded core in the product removal direction”.

The extruded core arrangement determining unit 136 is an embodiment of the extruded core arrangement determining unit according to the present invention. The extruded core whose arrangement (and shape) is determined by the extruded core arrangement determining unit 135 peels the product from the mold. Sometimes it is determined whether or not the product can be held in a state supported by the extruded core.
Substantially, the control device 130 performs a predetermined calculation in accordance with a mold design program stored in the control device 130, thereby fulfilling a function as the extruded core arrangement determination unit 136.

  The extruded core arrangement determining unit 136 determines whether or not the product peeled from the mold can be held by the extruded core according to the following procedures (A) to (D).

(A) The extruded core arrangement determination unit 136 sets the “extrusion effective range” based on the “center of gravity position of the projection shape in the product removal direction of the cavity element composite surface” calculated by the composite surface projection shape gravity center position calculation unit 135b. Set.
Here, the “extrusion effective range” refers to a range in which an extrusion force (force to peel the product from the cavity surface of the mold) by the extrusion core reaches the product. The effective extrusion range is set based on the mechanical properties (yield stress, longitudinal elastic modulus, transverse elastic modulus) of the raw material of the product, or based on knowledge of similar products in the past.
In the present embodiment, as shown in FIG. 7, the effective extrusion ranges 51L, 52L, 53L, 54L, 51R, 52R, 53R, and 54R are “the center of gravity of the projected shape in the product removal direction of the cavity element composite surface ( It is represented by a circle having a diameter of 400 mm centering around “displayed by a black circle in FIG. The shape and size of the effective extrusion range of this embodiment are stored in the storage device 120 in advance.
It should be noted that the shape and size of the effective extrusion range according to the present invention can be appropriately selected according to the product, and is not limited to a circle having a diameter of 400 mm as in the present embodiment.

(B) The extruded core arrangement determining unit 136 includes information related to the automotive bumper parting line 60 (see FIG. 7) stored in the storage device 120 and the previously set effective extrusion ranges 51L, 52L, 53L, and 54L.・ Based on 51R, 52R, 53R, and 54R, whether the outline of the effective extrusion range 51L, 52L, 53L, 54L, 51R, 52R, 53R, and 54R intersects the parting line 60 of the bumper for automobiles Check.
As a result of the above confirmation, as shown in FIG. 7, when the outlines of the effective extrusion ranges 51L, 52L, 53L, 54L, 51R, 52R, 53R, and 54R all intersect the parting line 60, the extruded core The arrangement determining unit 136 can maintain the state where the automotive bumper peeled from the mold by the extruded core is supported by the extruded core (the weight balance of the automotive bumper supported by the extruded core is broken. No).
As a result of the above confirmation, if at least one of the outlines of the effective extrusion range 51L / 52L / 53L / 54L / 51R / 52R / 53R / 54R does not intersect the parting line 60 of the automobile bumper In other words, it is impossible for the extruded core arrangement determining unit 136 to maintain the state in which the automotive bumper peeled from the mold by the extruded core is supported by the extruded core (the automotive bumper supported by the extruded core). Is determined to be out of balance.

(C) The extruded core arrangement determining unit 136 determines that it is impossible to maintain the state where the automotive bumper peeled from the mold by the extruded core is supported by the extruded core. A "product support core" that faces a position different from the cavity element composite surface in the bumper is set.
In the case of the present embodiment, the automobile bumper as a product generally has a substantially symmetrical shape with respect to the left-right direction, and tends to lose its weight balance with respect to the up-down direction. A “product support core” is additionally set at a position shifted either to the left or right side of the effective extrusion range that does not intersect the parting line 60 and to the vertical direction (direction approaching the parting line). To do.
The “product support core” stabilizes the posture of the product when the product peeled from the mold by the extruded core according to the present invention cannot hold the state supported by the extruded core. It is a core that is additionally set for this purpose.
The shape of the “product support core” is preset and stored in the storage device 120.

(D) The extrusion core arrangement determination unit 136 displays the arrangement of the extrusion core (or the combination of the extrusion core and the product support core) after the determination by the extrusion core arrangement determination unit 136 on the CAD terminal device 110. To do.
The worker determines the final arrangement of the extruded cores based on the arrangement of the extruded cores displayed on the CAD terminal device 110.
In the case of the present embodiment, the operator forms an opening in the mold to interfere with the cooling water path set in the mold, between the mechanism for opening and closing the mold and the extruded core, and to accommodate the extruded core. In consideration of the strength of the mold, etc., if necessary, the arrangement of the extruded core determined by the extruded core arrangement determining unit 135 is appropriately changed (usually moved in a direction perpendicular to the product removal direction). Or, an instruction to add a product support core is input to the CAD terminal device 110.
The extruded core arrangement determination unit 136 determines the final arrangement of the extruded core based on an instruction input to the CAD terminal device 110 by the operator.
The storage device 120 stores the final arrangement of the extruded core determined by the extruded core arrangement determination unit 136.

As described above, the CAD system 101 is
A system for designing a mold for molding a product (automobile bumper),
A product extraction angle calculation unit 132 that calculates a product extraction angle, which is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed in the mold and the product extraction direction, for each cavity element surface;
A cavity element surface extraction unit 133 that extracts a plurality of cavity element surfaces whose release resistance is greater than a predetermined threshold based on a relationship between a product extraction angle and a mold release resistance obtained in advance;
A cavity element composite surface setting unit 134 that sets a combination of a plurality of adjacent cavity element surfaces among the cavity element surfaces extracted by the cavity element surface extraction unit 133 as a cavity element composite surface;
An extruded core arrangement determining unit 135 that determines the arrangement of the extruded core facing the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface;
It comprises.
This configuration has the following advantages.
That is, since the CAD system 101 arranges the extrusion core at a position corresponding to the cavity element composite surface which is a portion having a large mold release resistance acting between the molded product and the cavity surface of the mold, Designed molds effectively the product after molding (without overloading the product (deforming the product), losing the attitude of the product, or scratching the surface of the product) It is possible to peel from the cavity surface.
Therefore, the CAD system 101 can easily and appropriately determine the arrangement of the extrusion core provided in the mold. Further, the CAD system 101 facilitates the arrangement of the extruded core, thereby contributing to the reduction of man-hours related to the design of the mold and consequently the design cost of the mold.

In addition, the extruded core arrangement determining unit 135 of the CAD system 101 is
The extruded core is arranged at a position where the center of gravity position of the projection shape of the cavity element composite surface in the product extraction direction and the center of gravity position of the projection shape in the product extraction direction of the extrusion core coincide with each other when viewed from the product extraction direction.
By configuring in this way, the CAD system 101 arranges the extruded core based on the center of gravity position of the cavity element composite surface. Therefore, the extruded core of the mold designed by the CAD system 101 is a product separated from the mold. It is possible to hold the supported state (support the product without changing its posture), and in the product manufacturing process, the product can be easily delivered to the subsequent process of the product molding process using the mold. Productivity is improved.

In addition, the extruded core arrangement determining unit 135 of the CAD system 101 is
Based on the projected shape area of the cavity element composite surface in the product removal direction and the projected shape area of the cavity element composite surface in the direction perpendicular to the product removal direction, the projected area of the extruded core in the product removal direction is calculated.
This configuration has the following advantages.
In other words, since the placement and shape (size) of the extruded core has been determined based on the experience of skilled workers, the determined size of the extruded core (projected area viewed from the product removal direction) is actually required. However, based on the projected shape area of the cavity element composite surface in the product removal direction and the projected shape area of the cavity element composite surface in the direction perpendicular to the product removal direction as in this embodiment. By calculating the projected area seen from the product extraction direction of the extruded core of the cavity element composite surface according to a certain rule, the projected area seen from the product removal direction of the extruded core is set to be relatively small compared to the conventional case. It is possible to reduce the manufacturing cost of the extruded core.

The CAD system 101 is
Extrusion core arrangement determination unit that determines whether or not the product supported by the extrusion core can be maintained when the extrusion core whose arrangement is determined by the extrusion core arrangement determination unit 135 peels the product from the mold. 136.
By comprising in this way, it can be confirmed whether the attitude | position of the product peeled from the metal mold | die is stable, and it contributes to the productivity improvement of a metal mold | die.

In addition, the extruded core arrangement determining unit 136 of the CAD system 101 is
Based on the position of the center of gravity of the projected shape of the cavity element composite surface, set the effective extrusion range, which is the range where the extrusion force by the extrusion core reaches the product,
When the outline of the effective range of extrusion intersects the parting line of the mold, it is determined that the product can be held in a state supported by the extruded core,
When the outline of the effective extrusion range does not intersect the parting line of the mold, it is determined that it is impossible to keep the product supported by the extruded core.
With this configuration, it is possible to easily and reliably determine whether or not it is possible to maintain the state in which the product is supported by the extruded core according to a certain standard.

In addition, the extruded core arrangement determining unit 136 of the CAD system 101 is
When it is determined that it is impossible to maintain the state in which the product is supported by the extruded core, a product support core that faces a position different from the cavity element composite surface in the product is set.
By comprising in this way, it is possible to hold | maintain the state in which the product was supported by the extrusion core reliably.

Below, one Embodiment of the metal mold | die design method which concerns on this invention is described using FIG.
One embodiment of a mold design method according to the present invention is a method for designing a mold for molding a bumper for an automobile, which is a product, using a CAD system 101. As shown in FIG. An element surface extraction step S1200, a cavity element composite surface setting step S1300, an extruded core arrangement determining step S1400, and an extruded core arrangement determining step S1500 are provided.

In the product extraction angle calculation step S1100, the “product extraction angle”, which is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed on the mold by the product extraction angle calculation unit 132 and the product extraction direction, is set for each cavity element. This is a step of calculating a surface.
When the product extraction angle calculation step S1100 is completed, the process proceeds to the cavity element surface extraction step S1200.

The cavity element surface extraction step S1200 is performed by the cavity element surface extraction unit 133 based on the “relation between the product drawing angle and the mold release resistance” previously determined, and among the plurality of cavity element surfaces constituting the cavity surface of the mold. This is a step of extracting a mold having a mold release resistance larger than a predetermined threshold value.
When the cavity element surface extraction step S1200 is completed, the process proceeds to the cavity element composite surface setting step S1300.

In the cavity element composite surface setting step S1300, a combination of a plurality of adjacent cavity element surfaces among the cavity element surfaces extracted by the cavity element composite surface setting unit 134 in the cavity element surface extraction step S1200 is referred to as “cavity element composite surface”. This is a step of setting as a “surface”.
When the cavity element composite surface setting step S1300 is completed, the process proceeds to the extruded core arrangement determining step S1400.

In the extruded core arrangement determining step S1400, the extruded core arrangement determining unit 135 faces the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface set in the cavity element composite surface setting step S1300. This is a step of determining the arrangement of the extruded core.
In the present embodiment, the extruded core arrangement determination step S1400 includes a composite surface projection shape creation step S1410, a composite surface projection shape centroid position calculation step S1420, a composite surface projection area calculation step S1430, and an arrangement determination step S1440.

In the composite surface projection shape creation step S1410, the composite surface projection shape creation unit 135a performs "projection shape of the cavity element composite surface set by the cavity element composite surface setting unit 134 in the product removal direction" and "cavity element composite surface setting unit 134. Is a step of creating a “projection shape in a direction perpendicular to the product removal direction of the cavity element composite surface set by the above”.
When the composite surface projection shape creation step S1410 is completed, the process proceeds to the composite surface projection shape center-of-gravity position calculation step S1420.

In the composite surface projection shape centroid position calculation step S1420, the composite surface projection shape centroid position calculation unit 135b calculates the centroid position of the projection shape in the product removal direction of the cavity element composite surface created by the composite surface projection shape creation unit 135a. It is.
When the composite surface projection shape center-of-gravity position calculation step S1420 ends, the process proceeds to the composite surface projection area calculation step S1430.

In the composite surface projected area calculation step S1430, the composite surface projected area calculation unit 135c creates the “projection shape of the cavity element composite surface in the product removal direction” and “product removal of the cavity element composite surface” created in the composite surface projection shape creation step S1410. Based on the “projection shape in the direction perpendicular to the direction”, “projection shape area in the product removal direction of the cavity element composite surface (projection area)” and “projection shape in the direction perpendicular to the product removal direction of the cavity element composite surface” This is a step of calculating “area (projected area)”.
When the composite surface projected area calculation step S1430 is completed, the process proceeds to an arrangement determination step S1440.

In the layout determination step S1440, the “positional center of gravity of the projection shape in the product removal direction of the cavity element composite surface” calculated by the layout determination unit 135d in the composite surface projection shape gravity center position calculation step S1420 is calculated in the composite surface projection area calculation step S1430. Based on the “projected area of the cavity element composite surface in the product removal direction” and the “projected area of the cavity element composite surface in the predetermined direction perpendicular to the product removal direction” calculated in the composite surface projected area calculation step S1430 This is a step of determining the shape and arrangement of the extruded core provided in the mold.
When the placement determining step S1440 is finished, the extruded core placement determining step S1400 is finished.
When the extruded core arrangement determining step S1400 is completed, the process proceeds to an extruded core arrangement determining step S1500.

  In the present embodiment, when the composite plane projection shape center of gravity position calculation step S1420 is completed, the process proceeds to the composite plane projection area calculation step S1430. However, the present invention is not limited to this, and the composite plane projection area calculation step and the composite plane are calculated. The order in which the surface projection shape center-of-gravity position calculation step is performed may be changed.

  In the extruded core arrangement determination step S1500, when the extruded core whose arrangement (and shape) is determined in the extruded core arrangement determination step S1400 peels the product from the mold, the state in which the product is supported by the extruded core is maintained. This is a step in which the extruded core arrangement determination determines whether or not this is possible.

  In the present embodiment, the extrusion core arrangement determination step S1500 includes an extrusion effective range setting step S1510, a parting line intersection determination step S1520, a product support core setting step S1530, and a final determination step S1540.

In the extrusion effective range setting step S1510, the extrusion core arrangement determination unit 136 calculates “extruded center of gravity of the projection shape in the product removal direction of the cavity element composite surface” calculated in the composite surface projection shape gravity center position calculation step S1420. This is a step of setting an “effective range”.
When the extrusion effective range setting step S1510 is completed, the process proceeds to a parting line intersection determination step S1520.

In the parting line intersection determination step S1520, the extrusion core arrangement determination unit 136 determines the effective extrusion range based on the information related to the parting line of the automobile bumper as a product and the effective extrusion range set in the effective extrusion range setting step S1510. Check if the outline intersects with the parting line of the car bumper,
Extrusion core when the outline of the effective extrusion range intersects the parting line of the automobile bumper (if multiple effective extrusion ranges are set, all of the multiple effective extrusion outlines) It is determined that the automotive bumper peeled from the mold can be held by the extruded core,
If the outline of the effective range of extrusion does not intersect the parting line of the bumper for automobiles (if multiple effective ranges of extrusion are set, at least one outline of the effective range of extrusions) This is a step of determining that it is impossible to maintain the state in which the automobile bumper peeled from the mold by the extruded core is supported by the extruded core.

In the parting line intersection determination step S1520, when it is determined that the automobile bumper peeled from the mold by the extruded core can be held in the state supported by the extruded core, the final determination step S1540 is performed. Transition.
In the parting line intersection determination step S1520, when it is determined that it is impossible to maintain the state in which the automobile bumper peeled from the mold by the extruded core is supported by the extruded core, the product is used for supporting the product. The process proceeds to core setting step S1530.

In the product support core setting step S1530, the extruded core arrangement determining unit 136 determines that it is impossible to maintain the state in which the automobile bumper peeled from the mold by the extruded core is supported by the extruded core. This is a step of setting a “product support core” that faces a position different from the cavity element composite surface in the automobile bumper.
When the product support core setting step S1530 ends, the process proceeds to a final determination step S1540.

The final determination step S1540 is an arrangement of the extruded core (or a combination of the extruded core and the product support core) after the extruded core arrangement determining unit 136 has performed the determination by the extruded core arrangement determining unit 136 on the CAD terminal device 110. And the operator determines the final arrangement of the extruded core based on the arrangement of the extruded core displayed on the CAD terminal device 110.
When the final determination step S1540 is completed, the extruded core arrangement determination step S1500 is ended.

As described above, one embodiment of the mold design method according to the present invention is as follows.
A mold design method for designing a mold for molding a product,
A product extraction angle calculation step S1100 for calculating a product extraction angle, which is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed in the mold and the product extraction direction, for each cavity element surface;
Cavity element surface extraction step S1200 for extracting a plurality of cavity element surfaces whose release resistance is greater than a predetermined threshold based on the relationship between the product extraction angle and the mold release resistance obtained in advance,
A cavity element composite surface setting step S1300 for setting, as a cavity element composite surface, a combination of a plurality of adjacent cavity element surfaces among the cavity element surfaces extracted in the cavity element surface extraction step;
An extruded core arrangement determining step S1400 for determining the arrangement of the extruded core facing the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface;
It comprises.
This configuration has the following advantages.
That is, one embodiment of the mold designing method according to the present invention is extruded to a position corresponding to the cavity element composite surface which is a portion having a large mold release resistance acting between the molded product and the cavity surface of the mold. Since the core is arranged, the mold designed according to the embodiment of the mold designing method according to the present invention can effectively use the molded product (additional load to the product (deform the product), etc.) The product can be peeled off from the cavity surface without causing the product to lose its position or damage the product surface.
Therefore, one embodiment of the mold design method according to the present invention can easily and appropriately determine the arrangement of the extrusion core provided in the mold. In addition, the embodiment of the mold design method according to the present invention facilitates the arrangement of the extruded core, thereby contributing to the reduction of man-hours related to the design of the mold and consequently the design cost of the mold.

An embodiment of the mold design method according to the present invention is as follows:
In the extruded core arrangement determining step S1400,
The extruded core is arranged at a position where the center of gravity of the projected shape in the product extraction direction of the cavity element composite surface and the center of gravity of the projected shape in the product extraction direction of the extruded core coincide with each other when viewed from the product extraction direction.
By configuring in this way, the embodiment of the mold design method according to the present invention arranges the extruded core based on the position of the center of gravity of the cavity element composite surface, so the implementation of the mold design method according to the present invention is performed. The extrusion core of the mold designed according to one form can hold the state where the product peeled from the mold is supported (support the product without changing its posture), and the mold in the manufacturing process of the product Product delivery to the subsequent process of the product molding process by the mold is facilitated, and the product productivity is improved.

An embodiment of the mold design method according to the present invention is as follows:
In the extruded core arrangement determining step S1400,
Based on the projected shape area of the cavity element composite surface in the product removal direction and the projected shape area of the cavity element composite surface in the direction perpendicular to the product removal direction, the projected area of the extruded core in the product removal direction is calculated.
This configuration has the following advantages.
In other words, since the placement and shape (size) of the extruded core has been determined based on the experience of skilled workers, the determined size of the extruded core (projected area viewed from the product removal direction) is actually required. However, based on the projected shape area of the cavity element composite surface in the product removal direction and the projected shape area of the cavity element composite surface in the direction perpendicular to the product removal direction as in this embodiment. By calculating the projected area seen from the product extraction direction of the extruded core of the cavity element composite surface according to a certain rule, the projected area seen from the product removal direction of the extruded core is set to be relatively small compared to the conventional case. It is possible to reduce the manufacturing cost of the extruded core.

An embodiment of the mold design method according to the present invention is as follows:
Extrusion Core Arrangement Determination Step S1400 Extrusion Core Arrangement Determination Step for Determining whether or not it is possible to hold the state where the product is supported by the extrusion core when the extrusion core is separated from the mold. S1500.
By comprising in this way, it can be confirmed whether the attitude | position of the product peeled from the metal mold | die is stable, and it contributes to the productivity improvement of a metal mold | die.

An embodiment of the mold design method according to the present invention is as follows:
In the extruded core arrangement determination step S1500,
Based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface, set the effective extrusion range where the extrusion force exerted by the extrusion core reaches the product,
When the outline of the effective range of extrusion seen from the product pulling direction intersects the parting line of the mold, it is determined that the product can be held in the state supported by the extruded core,
When the outline of the effective extrusion range does not intersect the parting line of the mold when viewed from the product pulling direction, it is determined that it is impossible to keep the product supported by the extruded core.
With this configuration, it is possible to easily and reliably determine whether or not it is possible to maintain the state in which the product is supported by the extruded core according to a certain standard.

An embodiment of the mold design method according to the present invention is as follows:
In the extruded core arrangement determination step S1500,
When it is determined that it is impossible to maintain the state in which the product is supported by the extruded core, a product support core that faces a position different from the cavity element composite surface in the product is set.
By comprising in this way, it is possible to hold | maintain the state in which the product was supported by the extrusion core reliably.

Hereinafter, an embodiment of a mold design program according to the present invention will be described.
An embodiment of a mold design program according to the present invention is a mold design program for designing a mold for molding a bumper for an automobile, which is a product, stored in a control device of a CAD system 101,
On the computer,
A product extraction angle calculation function for calculating a product extraction angle, which is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed in the mold and the product extraction direction, for each cavity element surface;
Based on the relationship between the product extraction angle and the mold release resistance obtained in advance, among the plurality of cavity element surfaces, a cavity element surface extraction function that extracts a mold release resistance greater than a predetermined threshold;
A cavity element composite surface setting function that sets a combination of a plurality of adjacent cavity element surfaces among the cavity element surfaces extracted by the cavity element surface extraction function as a cavity element composite surface;
Extruded core arrangement determination function for determining the arrangement of the extruded core facing the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface;
It is for realizing.
This configuration has the following advantages.
That is, the computer storing the embodiment of the mold design program according to the present invention corresponds to the cavity element composite surface that is a portion having a large release resistance acting between the molded product and the cavity surface of the mold. Since the extrusion core is arranged at the position where the mold is designed, the mold designed by the computer storing one embodiment of the mold design program according to the present invention effectively applies the product after molding (adds an extra load to the product). (Without deforming the product), losing the posture of the product, or scratching the surface of the product).
Therefore, the computer storing the embodiment of the mold design program according to the present invention can easily and appropriately determine the arrangement of the extrusion core provided in the mold. In addition, the computer storing the embodiment of the mold design program according to the present invention facilitates the arrangement of the extrusion core, thereby contributing to the reduction of the man-hours related to the mold design and consequently the mold design cost. .

Hereinafter, an embodiment of a computer-readable storage medium storing a mold design program according to the present invention will be described.
One embodiment of a computer-readable storage medium storing a mold design program according to the present invention is stored in a control device of a CAD system 101, and a mold for designing a mold for molding a bumper for an automobile as a product. A mold design program stored in a computer-readable storage medium,
On the computer,
A product extraction angle calculation function for calculating a product extraction angle, which is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed in the mold and the product extraction direction, for each cavity element surface;
Based on the relationship between the product extraction angle and the mold release resistance obtained in advance, among the plurality of cavity element surfaces, a cavity element surface extraction function that extracts a mold release resistance greater than a predetermined threshold;
A cavity element composite surface setting function that sets a combination of a plurality of adjacent cavity element surfaces among the cavity element surfaces extracted by the cavity element surface extraction function as a cavity element composite surface;
Extruded core arrangement determination function for determining the arrangement of the extruded core facing the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface;
It is for realizing.
This configuration has the following advantages.
That is, the computer that reads the mold design program from one embodiment of the computer-readable storage medium that stores the mold design program according to the present invention operates between the molded product and the cavity surface of the mold. Since the extruded core is disposed at a position corresponding to the cavity element composite surface, which is a portion having a high mold release resistance, the mold can be obtained from an embodiment of a computer-readable storage medium storing the mold design program according to the present invention. A mold designed by a computer that has read the mold design program effectively processes the product after molding (adding an extra load to the product (deforming the product), distorting the product posture, or the surface of the product. It is possible to peel from the cavity surface (without scratching the surface).
Therefore, the computer that has read the mold design program from the embodiment of the computer-readable storage medium that stores the mold design program according to the present invention can easily and appropriately determine the arrangement of the extrusion core provided in the mold. Is possible. In addition, the computer that has read the mold design program from the embodiment of the computer-readable storage medium that stores the mold design program according to the present invention facilitates the arrangement of the extrusion core, thereby designing the mold. This contributes to the reduction of man-hours related to the above, and consequently the design cost of the mold.
Specific examples of the “computer-readable storage medium” include a flexible disk cartridge, a memory card, a CD-ROM, a DVD-ROM, and an HDD.

The figure which shows 1st embodiment of the metal mold | die design system which concerns on this invention. The figure which shows 2nd embodiment of the metal mold | die design system which concerns on this invention. The figure which shows an example of a parting model. The figure which shows the relationship between a product extraction angle and mold release resistance. The schematic diagram which shows a cavity element surface and a cavity element composite surface. The figure which shows the relationship between the projection shape in the product extraction direction of the cavity element composite surface, the cavity element composite surface, and the direction perpendicular to the product extraction direction of the cavity element composite surface. The figure which shows the relationship between the parting line of a product, and an extrusion effective range. The flowchart which shows one Embodiment of the metal mold | die design method which concerns on this invention.

Explanation of symbols

101 CAD system (mold design system)
DESCRIPTION OF SYMBOLS 110 CAD terminal device 120 Memory | storage device 130 Control apparatus 131 CAD function processing part 132 Product extraction angle calculation part 133 Cavity element surface extraction part 134 Cavity element compound surface setting part 135 Extrusion core arrangement | positioning determination part 136 Extrusion core arrangement | positioning determination part

Claims (24)

A mold design method for designing a mold for molding a product,
A product extraction angle calculation step of calculating a product extraction angle, which is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed in the mold and the product extraction direction, for each cavity element surface;
Cavity element surface extraction step for extracting, among the plurality of cavity element surfaces, the one having the release resistance larger than a predetermined threshold, based on the relationship between the product extraction angle and the mold release resistance obtained in advance.
A cavity element composite surface setting step of setting a combination of a plurality of adjacent cavity element surfaces among the cavity element surfaces extracted in the cavity element surface extraction step as a cavity element composite surface;
An extruded core arrangement determining step for determining the arrangement of the extruded core facing the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface;
A mold design method comprising: In the extruded core arrangement determining step,
The extruded core is disposed at a position where the center of gravity of the projected shape in the product extraction direction of the cavity element composite surface and the center of gravity of the projected shape in the product extraction direction of the extruded core coincide with each other when viewed from the product extraction direction. 2. The mold design method according to 1. In the extruded core arrangement determining step,
The projected area of the extruded core in the product removal direction is calculated based on the projected shape area of the cavity element composite surface in the product removal direction and the projected shape area of the cavity element composite surface in the direction perpendicular to the product removal direction. Item 3. A mold design method according to Item 2.   Extrusion core for determining whether or not the extruded core whose arrangement is determined in the extruded core arrangement determining step can hold the state where the product is supported by the extruded core when the product is peeled from the mold. The mold design method according to any one of claims 1 to 3, further comprising an arrangement determination step. In the extruded core arrangement determining step,
Based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface, an effective extrusion range is set in which the extrusion force by the extrusion core reaches the product,
When the outline of the effective range of extrusion seen from the product pulling direction intersects the parting line of the mold, it is determined that the product can be held in the state supported by the extruded core,
When the outline of the effective range of extrusion does not intersect the parting line of the mold when viewed from the product pulling direction, it is determined that it is impossible to keep the product supported by the extruded core. The mold design method according to claim 4. In the extruded core arrangement determining step,
The product support core is set to face the position different from the cavity element composite surface in the product when it is determined that the product cannot be held in the state supported by the extruded core. The mold design method described. A mold design system for designing a mold for molding a product,
A product extraction angle calculation unit for calculating a product extraction angle, which is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed in the mold and the product extraction direction, for each cavity element surface;
Based on the relationship between the product extraction angle determined in advance and the mold release resistance, among the plurality of cavity element surfaces, a cavity element surface extraction unit that extracts the mold release resistance greater than a predetermined threshold;
Among the cavity element surfaces extracted by the cavity element surface extraction unit, a cavity element composite surface setting unit that sets a combination of a plurality of adjacent cavity element surfaces as a cavity element composite surface;
An extruded core arrangement determining unit that determines the arrangement of the extruded core facing the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface;
A mold design system comprising: The extruded core arrangement determining unit is
The extruded core is disposed at a position where the center of gravity of the projected shape in the product extraction direction of the cavity element composite surface and the center of gravity of the projected shape in the product extraction direction of the extruded core coincide with each other when viewed from the product extraction direction. 8. The mold design system according to 7. The extruded core arrangement determining unit is
The projected area of the extruded core in the product removal direction is calculated based on the projected shape area of the cavity element composite surface in the product removal direction and the projected shape area of the cavity element composite surface in the direction perpendicular to the product removal direction. Item 9. The mold design system according to Item 8.   Extrusion core for determining whether or not the extruded core whose arrangement has been determined by the extruded core arrangement determining unit can maintain the state in which the product is supported by the extruded core when the product is peeled from the mold. The mold design system according to any one of claims 7 to 9, further comprising an arrangement determination unit. The extruded core arrangement determining unit
Based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface, an effective extrusion range is set in which the extrusion force by the extrusion core reaches the product,
When the outline of the effective range of extrusion seen from the product pulling direction intersects the parting line of the mold, it is determined that the product can be held in the state supported by the extruded core,
When the outline of the effective range of extrusion does not intersect the parting line of the mold when viewed from the product pulling direction, it is determined that it is impossible to keep the product supported by the extruded core. The mold design system according to claim 10. The extruded core arrangement determining unit
12. The product support core is set to face the position different from the cavity element composite surface in the product when it is determined that the product cannot be held in a state supported by the extruded core. The mold design system described. A mold design program for designing a mold for molding a product,
On the computer,
A product extraction angle calculation function for calculating a product extraction angle, which is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed in the mold and the product extraction direction, for each cavity element surface;
Cavity element surface extraction function for extracting, from among the plurality of cavity element surfaces, the one having the release resistance larger than a predetermined threshold, based on the relationship between the product extraction angle and the mold release resistance obtained in advance.
A cavity element composite surface setting function for setting a cavity element composite surface as a combination of a plurality of adjacent cavity element surfaces among the cavity element surfaces extracted by the cavity element surface extraction function;
An extruded core arrangement determining function for determining the arrangement of the extruded core facing the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface;
Die design program to realize The extruded core arrangement determining function is
The extruded core is disposed at a position where the center of gravity of the projected shape in the product extraction direction of the cavity element composite surface and the center of gravity of the projected shape in the product extraction direction of the extruded core coincide with each other when viewed from the product extraction direction. 13. A mold design program according to 13. The extruded core arrangement determining function is
The projected area of the extruded core in the product removal direction is calculated based on the projected shape area of the cavity element composite surface in the product removal direction and the projected shape area of the cavity element composite surface in the direction perpendicular to the product removal direction. Item 15. A mold design program according to Item 14. On the computer,
Extrusion core for determining whether or not the extruded core whose arrangement is determined by the extruded core arrangement determining function can hold the state in which the product is supported by the extruded core when the product is peeled from the mold. The mold design program according to any one of claims 13 to 15 for realizing an arrangement determination function. The extruded core arrangement determination function is
Based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface, an effective extrusion range is set in which the extrusion force by the extrusion core reaches the product,
When the outline of the effective range of extrusion seen from the product pulling direction intersects the parting line of the mold, it is determined that the product can be held in the state supported by the extruded core,
When the outline of the effective range of extrusion does not intersect the parting line of the mold when viewed from the product pulling direction, it is determined that it is impossible to keep the product supported by the extruded core. The mold design program according to claim 16. The extruded core arrangement determination function is
The product support core may be set to face a position different from the cavity element composite surface in the product when it is determined that the product cannot be supported by the extruded core. The mold design program described. A computer-readable storage medium storing a mold design program for designing a mold for molding a product,
On the computer,
A product extraction angle calculation function for calculating a product extraction angle, which is an angle formed by a plurality of cavity element surfaces constituting the cavity surface formed in the mold and the product extraction direction, for each cavity element surface;
Cavity element surface extraction function for extracting, from among the plurality of cavity element surfaces, the one having the release resistance larger than a predetermined threshold, based on the relationship between the product extraction angle and the mold release resistance obtained in advance.
A cavity element composite surface setting function for setting a cavity element composite surface as a combination of a plurality of adjacent cavity element surfaces among the cavity element surfaces extracted by the cavity element surface extraction function;
An extruded core arrangement determining function for determining the arrangement of the extruded core facing the cavity element composite surface based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface;
A computer-readable storage medium storing a mold design program for realizing the above. The extruded core arrangement determining function is
The extruded core is disposed at a position where the center of gravity of the projected shape in the product extraction direction of the cavity element composite surface and the center of gravity of the projected shape in the product extraction direction of the extruded core coincide with each other when viewed from the product extraction direction. A computer-readable storage medium storing the mold design program according to 19. The extruded core arrangement determining function is
The projected area of the extruded core in the product removal direction is calculated based on the projected shape area of the cavity element composite surface in the product removal direction and the projected shape area of the cavity element composite surface in the direction perpendicular to the product removal direction. Item 20. A computer-readable storage medium storing the mold design program according to Item 20.   Extrusion core for determining whether or not the extruded core whose arrangement is determined by the extruded core arrangement determining function can hold the state in which the product is supported by the extruded core when the product is peeled from the mold. A computer-readable storage medium storing the mold design program according to any one of claims 19 to 21 for realizing an arrangement determination function. The extruded core arrangement determination function is
Based on the position of the center of gravity of the projected shape in the product removal direction of the cavity element composite surface, an effective extrusion range is set in which the extrusion force by the extrusion core reaches the product,
When the outline of the effective range of extrusion seen from the product pulling direction intersects the parting line of the mold, it is determined that the product can be held in the state supported by the extruded core,
When the outline of the effective range of extrusion does not intersect the parting line of the mold when viewed from the product pulling direction, it is determined that it is impossible to keep the product supported by the extruded core. A computer-readable storage medium storing the mold design program according to claim 22. The extruded core arrangement determination function is
The product support core is set to face a position different from the cavity element composite surface in the product when it is determined that it is impossible to keep the product supported by the extruded core. A computer-readable storage medium storing the described mold design program.

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