JP4192769B2 - Creation method of shape model of mold or rough shape - Google Patents

Description

  The present invention relates to a method for creating a shape (model) of a mold or a mold product (coarse shape material).

Today, a rough shape material model that represents the three-dimensional shape of a rough shape material such as a mold product and a die model that represents the three-dimensional shape of the die used for the molding are created by three-dimensional CAD. It has become common. Conventionally, when creating these models on CAD, first, a prototype model creation process for creating a prototype model (no fillet surface, no draft) of a previously created product is performed, and then this prototype model (no fillet surface, no extraction). Original surface (no fillet surface, no draft angle), which is a surface with no gradient), can be divided into multiple divided surfaces (usually can be machined by continuous operation of the same tool) in consideration of mold forming, especially for ease of machining and punching. Execute the splitting process to split, and then execute the fillet surface forming process to form a connecting surface (fillet surface) smoothly connected to these split surfaces at the boundary between two split surfaces with different angles. gradient running draft forming process to provide a draft angle required split surface had a roughness profile model and it showing the shape of a coarse profile and creating a mold model showing the mold shape for molding . As a fillet surface creation method using CAD, for example, the following Patent Document 1 has been proposed.
Japanese Patent No. 2638852

  However, in the creation work of the rough shape model and the die model by the above-mentioned conventional CAD, especially the creation work of the fillet surface and draft surface, fillet surface creation calculation and draft angle for each fillet surface required area on the CAD. It is necessary to perform a surface creation operation, which takes a lot of time and labor to create a CAD model, and further, the shape of the fillet surface and draft surface may not be unified due to variations in operator preference.

  In addition, when the mold surface corresponding to the molding surface of the rough profile model created on the CAD is converted into NC processing data to perform the die processing, Of course, machining operations that faithfully reproduce the draft plane are performed. However, it takes time to create NC machining data because of the processing of complex fillet surfaces and draft planes created on these CAD, and this NC machining data is used. The actual NC machining that has been performed has also become complicated, resulting in an increase in mold costs.

  The present invention has been made in view of the above-described problems. For example, a mold or a rough shape that can simplify the shape design and mold manufacturing operation of a mold having a fillet surface or a draft surface or a mold-molded product, and a mold manufacturing operation. The purpose, that is, the subject, is to realize a method for creating a model of a material.

The model creation method according to the first aspect of the present invention is to prepare an original model consisting of an original shape surface representing a basic three-dimensional shape of a rough shape member or a mold, and to create the original shape surface with a predetermined processing tool. A machining simulation is performed to machine the original surface based on the NC machining data with the machining tool or a machining tool having a shape similar to the machining tool, and the original model is formed according to the shape of the machining tool during the machining simulation. get a new surface not in the original model, which is newly assigned, it is characterized by creating a completed model by obtaining pressurizing the new surface to the original shape of the original model. In this way, a new surface created by the tool shape is fed back to the original model on the CAD by performing a machining simulation using a tool having a specific shape, thus simplifying the surface creation work on the CAD. In addition, in actual machining, this new surface can be automatically created by the original surface machining of the original model, so that the actual machining operation can be simplified.

  In addition, the processing simulation used in the present invention can be used to easily and accurately estimate the time required for mold processing and the cost for manufacturing a mold or a rough shape material. It is also possible to achieve an effect that it is possible to efficiently carry out repeated design changes for converging those actual costs within a range allowed as a product manufacturing cost and a die manufacturing cost within that range.

According to the model creation method of the second invention, an original model representing a basic three-dimensional shape of a rough shape material or a mold in which a fillet surface is not formed at a boundary portion between two adjacent surfaces adjacent to each other in a concave shape is prepared. Then, NC machining data is created on the assumption that the original model is created with a predetermined rotary machining tool, and the NC machining data is created using a rotary machining tool with a hemispherical tip having the same diameter and round tip as the rotary machining tool. Based on the hemisphere at the time of the machining simulation by carrying out a machining simulation for machining at least one of the two surfaces connected to the boundary at a predetermined or all of the boundaries of the original model and creating a concave R surface as the fillet surface to the boundary as the locus plane of the forward end surface, El pressurizing the concave R surface which is created in the original shape of the original model This is characterized by creating a completed model that is a model with a fillet surface.

  The “adjacent two surfaces adjacent to each other in a concave shape” as used herein refers to two adjacent surfaces whose space angle between two surfaces is less than a predetermined angle (at least less than 180 degrees) in the space between the surfaces. . When one of these two adjacent surfaces is created by machining on the rotating side surface of the rotary processing tool with a hemispherical tip, the boundary R cannot be machined by the tip R shape of the hemispherical tip, and the concave R surface. Remains as. When the original model is an original model of a mold, a concave R surface of the mold model creates a convex R surface as a fillet surface in the rough material model molded by the mold model. When the original shape model is a rough shape material model, a convex R surface as a fillet surface is created in the mold model for forming the rough shape material model by the concave R surface of the rough shape material model.

  Here, “substantially adding the created concave R-surface to the original shape of the original model” means that the corresponding boundary of the original shape of the original model is changed to the created concave R-surface, It may be a case where all models obtained by the machining simulation, that is, all shapes are acquired.

   For example, in the present invention, an original model without fillet surface processing created on a CAM system is converted into NC machining data by a CAM system (CAM program), and this NC machining data is converted into, for example, a ball end mill by a simulator (simulation program). Virtual machining is performed with such a tool having an R-shaped tip. The simulated processing may be performed on all surfaces of the original model that need to be processed, or may be performed only on the surfaces that are connected to the boundary where the fillet surface is to be created. As a result, a concave R surface is formed as a processing residue of the tip portion of the tool at the boundary, and this concave R surface can be used as a fillet surface.

  In this way, since the surface shape requirements for most fillet surfaces are not so strict, all the parts of the original model that require the fillet surface are called on the CAD screen, and the conventional fillet surface is created by specifying the part. It is not necessary to execute fillet surface creation processing by a program one by one, and the shape of each fillet surface can be unified, and model creation work can be simplified and speeded up. In addition, since the actual mold processing for creating the fillet surface is simplified, the mold processing operation can be facilitated and the processing time can be shortened. In addition, it is only necessary to select a part for which a special fillet surface needs to be created and execute a conventional CAD program for creating a fillet surface. Not necessary.

  In addition, the processing simulation used in the present invention can be used to easily and accurately estimate the time required for mold processing and the cost for manufacturing a mold or a rough shape material. It is also possible to achieve an effect that it is possible to efficiently carry out repeated design changes for converging those actual costs within a range allowed as a product manufacturing cost and a die manufacturing cost within that range.

  In a preferred embodiment, a rotating tool with a hemispherical tip used to form the concave R surface in the rough shape model, and the concave R surface are formed in a mold for forming the rough shape model. It is preferable to use the same rotating tool with a hemispherical tip used for the above. In this way, the convex R surface and the concave R surface, which are the fillet surfaces of the rough shape model actually manufactured, are approximated, and therefore, the appearance is excellent.

  In a preferred embodiment, the rotary tool with a hemispherical tip having a size that satisfies the shape required for the fillet surface is selected, and the rotary tool with the hemispherical tip of the type is used in the actual creation of the completed model. Is specified. As a result, the fillet surface can be formed automatically when the surface connected to the fillet surface is simply processed without actually performing special processing.

According to the model creation method of the third aspect of the invention, an original model representing a basic three-dimensional shape of a mold in which no draft is formed on the draft required surface is prepared, and the original model is processed with a predetermined rotational processing tool. NC machining data is created as an object to be created, and the draft required surface is machined based on the NC machining data using a rotary machining tool with a taper having a predetermined taper surface and approximately the same diameter as the rotary machining tool. by performing a machining simulation, wherein by creating the inclined surface bleeding in the draft required surface as the locus plane of the tapered surface at the time of machining simulation, El pressurizing the draft surface that is created in the original shape of the original model This is characterized by creating a completed model, which is a model with a draft surface.

  The draft required surface here refers to a surface parallel to the axial direction of the rotary machining tool for machining the original model as a mold model. The rotary machining tool performs a movement parallel to the axis and a movement perpendicular to the axis. The axial direction of the rotary machining tool, that is, the orientation of the rotary machining tool is the direction parallel to the direction when there is no draft of the draft required surface, at least when machining the draft required surface. Is selected to match.

  The phrase "substantially add the created draft surface to the original shape of the original model" means to change the corresponding draft required surface of the original shape of the original model to the created draft surface. In addition, the model obtained by the machining simulation, that is, the case where all the shapes are obtained may be used.

  For example, according to the present invention, NC machining data indicating the movement (trajectory) of a non-tapered rotary machining tool is created by a CAM system on a draft required surface of a mold model created on a CAD system. Thereby, this draft required surface can be processed without draft. Next, using this NC machining data, the simulator of the tool is transferred to this draft required surface by performing a machining simulation with a rotary machining tool having a taper that is approximately the same diameter as the taper and the above-mentioned taper rotation machining tool. The draft required surface is virtually processed into a draft surface. By providing the draft angle surface obtained in this way in the mold model, the draft angle is required all at once without executing the process of providing the draft angle on the draft required surface of the mold model on the CAM system. The draft can be provided on the surface, and the model creation work can be simplified and speeded up. In addition, since the actual mold processing for creating the draft surface need only specify that the rotary processing tool is tapered, the mold processing operation can be facilitated and the processing time can be shortened. Note that it is possible to specify that a surface that can be machined by the tapered rotary machining tool among the surfaces other than the draft surface of the mold model is machined by the tapered rotary machining tool.

  In addition, the processing simulation used in the present invention can be used to easily and accurately estimate the time required for mold processing and the cost for manufacturing a mold or a rough shape material. It is also possible to achieve an effect that it is possible to efficiently carry out repeated design changes for converging those actual costs within a range allowed as a product manufacturing cost and a die manufacturing cost within that range.

  In a preferred embodiment, the tapered rotary machining tool having a taper corresponding to the draft of the draft required surface is selected, and the type of tapered rotary machining tool is designated in the actual creation of the completed model.

In the model creation method of the fourth invention , a fillet surface is not formed at a boundary portion between two adjacent surfaces adjacent to each other in a concave shape, and a draft is not formed on the draft required surface connected to the boundary portion. An original model representing the three-dimensional shape of the mold is prepared, NC machining data is created as the original model is processed by a non-tapered rotary tool, and a predetermined taper surface is formed with substantially the same diameter as the non-tapered rotary tool. Based on the NC machining data using a rotating tool with a tapered hemispherical tip, the draft required surface connected to the boundary portion at a predetermined or all of the boundary portions of the original model By performing a machining simulation, the draft surface is formed on the draft required surface, and the fillet surface connected to the draft surface is formed on the boundary portion. Of a concave R surface formed by addition of the was created concave R surface and the draft surface to the original shape of the original model, creating a complete model is draft plane model. If it does in this way, for the above-mentioned reason, the model processing and actual processing for creating both a fillet surface and draft angle can be made simple and high-speed.

  In addition, although an end mill is suitable as an above-described rotary processing tool, it is not limited to an end mill. As the end mill, a flat end mill or a ball end mill can be employed, and an end mill having no taper on the side surface (straight) or an end mill having a taper taper on the side surface (taper) can be employed. In addition to the conversion to the above processing data and the processing simulation, not only for all surfaces of the original model, but also only for the surface connected to the boundary where the fillet surface needs to be created or the surface requiring the draft angle. Good.

Preferred embodiments of the present invention will be described below with reference to the drawings. However, the present invention is not limited to this embodiment, and it is needless to say that the present invention can be used to determine the surface shape of an industrial product that can utilize the idea of the present invention. In this embodiment, it is assumed that a rough shape material model that is a surface shape of a rough shape material that is a mold product and a die model that is a surface shape of a die used for the molding are created. However, in this embodiment, the mold model is divided into four nesting models that are surface shapes of nesting, but it goes without saying that other configurations known as mold models can be adopted. Yes.
(Device configuration)
FIG. 1 shows an apparatus configuration and a model creation procedure used in this embodiment. Reference numeral 1 denotes a CAD system, 2 denotes a CAM system, 3 denotes a machining simulator, and 4 denotes a database, which are connected so as to be able to exchange data at high speed. The CAD system 1, the CAM system 2, and the processing simulator 3 are all types that process a three-dimensional shape. As this type of CAD system 1, CAM system 2, machining simulator 3 and database 4, commercially available ones are sufficient and are already well known, so description of the configuration thereof will be omitted. In addition, since the essence of the CAD system 1, the CAM system 2, and the machining simulator 3 is software processing, these devices can perform processing operations, data input / output operations, and display operations of these software (programs). Of course, other data processing devices may be used if feasible. As will be described later, the database 4 is assumed to store data relating to the shape and operation of tools that can be used for die machining, that is, tool information. In this embodiment, the tool used for die machining is a ball end mill driven by an NC machine or a machining center, but the present invention is not limited to this, and a known die such as a flat end mill or electric discharge machining is used. It is also possible to employ processing means. In electric discharge machining, the electrode corresponds to the tool in this embodiment.
(Details of model creation procedure)
Details of the model creation procedure will be described in turn below. However, it is assumed that a rough shape original shape model (original shape model referred to in the present invention) which is an original (basic) shape of a molded product (rough shape material) is created in advance as CAD data. However, it is assumed that the rough shape original model does not have a fillet surface or draft angle.

(Surface division process)
First, as shown in FIG. 2, a surface dividing process is performed using the CAD system 1. In this surface dividing step, the rough shape original model 5 is divided into a suitable number of divided surfaces in consideration of the insertion direction of the insert, and each divided surface is used as a molding surface (cavity surface) of each insert 11 to 14. Each nested model (initial). These nested models (initial stage) are collectively referred to as a mold original model. In FIGS. 1 and 11, the rough shape original model is referred to as a basic model (correlation shape) or a basic model.

(Processing data creation process 1)
Next, the machining data creation step 1 is performed using the CAM system 2. In this machining data creation step 1, each nested model (initial stage) is converted into NC machining data suitable for the machining center to be used. Machining data essentially includes determination of the tool and determination of the operation of the tool. In this embodiment, a ball end mill (straight) is used as a tool.

  A suitable tool movement pattern is shown in FIGS. The creation of the machining data includes a fillet surface creation step of smoothly connecting the two surfaces by creating a fillet surface in a boundary region between two surfaces adjacent to the concave shape of the nested model (initial stage). However, in this embodiment, the shape of all fillet surfaces can be determined entirely by the shape and operation of a ball end mill, which is a processing data creation tool for processing a surface connected to the fillet surface. Of course, there may exist a modification in which only a part of the fillet surface can determine the surface connected to the fillet surface described above by the shape and operation of the ball end mill. In this case, the other fillet surface is created by a fillet surface creation program of the CAD system and formed by another tool such as another end mill. In this embodiment, as shown in FIG. 3 and FIG. 4, a tool (called a tool for creating processing data) is used in accordance with the R value of each fillet surface created on the molding surface of each nested model (initial). The ball end mill 6 is selected for NC machining data creation. Note that a ball end mill (taper) may be used as a machining data creation tool.

(Processing simulation process 1)
Next, a machining simulation process 1 is performed using the machining simulator 3. FIG. 5 is a conceptual diagram showing the machining simulation process 1, and FIG. 6 shows an example of the nested model (intermediate) obtained by the machining simulation process 1. In this machining simulation step 1, first, a material model (usually a block material) 7 suitable for each nested model (initial stage) is defined, and a machining simulation is performed using the machining data obtained in the machining data creation step 1. The R value (hereinafter also referred to as the tip R value) of the tip of a ball end mill (referred to as a machining simulation tool) used in this machining simulation is the ball end mill used in the machining data creation step 1, that is, a machining data creation tool. The same value as the tip R value of. However, the side shape of the machining simulation tool is a taper shape having a taper angle that matches the draft angle in order to form a draft angle on the side surface of the molding surface of the nested model. That is, a ball end mill (taper) 8 is employed as a machining simulation tool. However, it is assumed that the axis of the ball end mill (taper) 8 coincides with the nesting direction.

  As a result, a concave R surface corresponding to the tip R value of the tool is created as a fillet surface on the surface where the fillet surface of the molding surface of the nesting model is required, that is, the boundary between the two surfaces). A nested model (intermediate) 9 in which a draft corresponding to the taper shape of the tool is created on the side surface, that is, the draft required surface, is formed.

  Naturally, the fact that a concave R surface corresponding to the tip R value of the tool is created in the nested model (intermediate) 9 means that the rough shape model (intermediate) described later corresponding to the surface of the nested model (intermediate) This means that a convex R surface is created as a fillet surface on the corresponding surface. The concave R surface and draft angle of the nested model (intermediate) 9 can be very easily formed by a ball end mill (taper). FIG. 7 shows the shape of the ball end mill (taper) 8 with the taper exaggerated. It can be seen that the ball end mill (taper) 8 forms a draft and a concave R (convex R on the rough profile model side) on the nested model (intermediate) 9 side.

If the corresponding part of the nesting model requires only a concave R surface, a ball end mill (straight) may be used in the machining simulation. If only a draft angle is required, a flat end mill is used instead of the ball end mill. (Taper) may be used. (Surface synthesis process)
Next, a surface synthesis process is performed using the CAD system 1. In this surface synthesizing process, the molding surface of each nested model (intermediate) 11-14 created in the machining simulation process is extracted as surface data and combined according to the layout of the nested structure model 15 (intermediate). Create. Accordingly, the rough shape model (intermediate) 15 has the convex R and draft as described above, but the concave R is not yet formed as described later. FIG. 8 is a conceptual diagram showing the surface synthesis process.

(Processing data creation process 2)
Next, the machining data creation step 2 is performed using the CAM system 2. In the machining data creation process 2, the rough shape model (intermediate) 15 obtained in the surface synthesis process is converted into machining data for the machining center used this time. However, the ball end mill (straight) selected in the machining data creation step 1 is employed as the tool at this time. However, the ball end mill (taper) used in the machining simulation 1 may be employed. As shown in FIG. 9, this machining data is created for each surface region of the rough shape model (intermediate) divided into each of the inserts 11 to 14 from the direction corresponding to the removal direction of each insert. Is done.

(Machining simulation process 2)
Next, a machining simulation process 2 is performed using the machining simulator 3. A conceptual diagram showing the machining simulation process 2 is shown in FIG. In this machining simulation step 2, first, a material model (block material) 16 including a rough shape material model (intermediate) 15 is defined, and machining data of the rough shape material model (intermediate) obtained in the machining data creation step 2 is used. To create a rough shape model (final). As the tool at this time, the ball end mill (taper) 8 selected in the machining simulation 1 is employed. In this rough profile model (final), a recess R is created as a machining residue by the tip R of the tool in the current machining simulation. As a result, the rough shape model (final) is substantially a shape obtained by adding the above-described convex R surface, concave R surface, and draft angle surface to the rough shape original shape model. The concave R surface given to the rough shape model (final) becomes a convex R surface in the corresponding die model (nesting model). Then, these convex R surface, concave R surface, and draft angle surface are extracted, and the surface of the corresponding part of the rough shape original model is replaced with these surfaces to obtain a rough shape completed model. However, as shown in FIG. 11, the rough profile model (final) obtained in the machining simulation step 2 may be used as the rough profile completion model.

The flow of each process described above is shown in FIG. The machining data creation is performed by acquiring tool information that is data related to the shape and movement of the tool necessary for creating the machining data from the database 4.
(Modification)
The creation order of the convex R surface, the concave R surface, and the draft surface described above is not limited to the above order, and can be changed as appropriate.
(Example effect)
In the embodiment described above, the machining tools for each nested model are all common. Thereby, the model creation work and the die machining work can be further simplified and speeded up.

It is a conceptual diagram which shows the apparatus structure and model creation procedure which are used in an Example. It is a schematic diagram which shows a surface division | segmentation process. It is a schematic diagram which shows an example of suitable tool operation | movement in the process data creation process 1. FIG. It is a mimetic diagram showing other examples of suitable tool operation in processing data creation process 1. It is a schematic diagram showing the process simulation process 1. FIG. It is a schematic diagram which shows an example of the nesting model (middle) obtained by the process simulation process 1. FIG. It is a schematic diagram which shows the shape of a ball end mill (taper). It is a schematic diagram which shows a surface synthesis process. It is a schematic diagram which shows the process data creation process 2. FIG. It is a schematic diagram which shows the process simulation process 2. FIG. It is a flowchart which shows the whole process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 CAD system 2 CAM system 3 Processing simulator 4 Database 5 Rough shape original model 6 Ball end mill (straight)
7 Material model (block material)
8 Ball end mill (taper) 8
9 Nested model (intermediate)
11 Nested 12 Nested 13 Nested 14 Nested 15 Coarse profile model (intermediate)

Claims (6)

Prepare a prototype model consisting of a prototype surface representing the basic three-dimensional shape of the rough profile or mold,
NC machining data is created by creating the original surface with a predetermined machining tool,
A machining simulation for machining the original surface based on the NC machining data with the machining tool or a machining tool having a shape similar to the machining tool,
Acquiring a new surface not in the original model newly added to the original model according to the shape of the processing tool during the processing simulation;
Model creation method characterized by creating a completed model by obtaining pressurizing the new surface to the original shape of the original model. Prepare an original model that represents the three-dimensional shape of a rough shape material or mold in which a fillet surface is not formed at the boundary between adjacent two surfaces that are adjacent in a concave shape,
NC machining data is created as the original model is created with a predetermined rotary machining tool,
Based on the NC machining data using a rotary machining tool with a hemispherical tip having the same diameter as the rotary machining tool and a rounded tip, the predetermined model or the whole of the boundary parts of the original model By performing a machining simulation for machining at least one of the two surfaces connected to the boundary portion, a concave R surface as the fillet surface is created in the boundary portion as a locus surface of the surface of the hemispherical tip portion during the machining simulation. ,
By obtaining pressure to created by said concave R surface to the original shape of the original model, the model creating method characterized by creating a complete model is a model with fillet surface. The model creation method according to claim 2,
A model that selects the hemispherical tip rotation processing tool having a size that satisfies the shape required for the fillet surface, and designates the type of hemispherical tip rotation processing tool in actual creation of the completed model. Creation method. Prepare an original model that represents the three-dimensional shape of the mold with no draft on the draft required surface,
NC machining data is created as the original model is created with a predetermined rotary machining tool,
By performing a machining simulation for machining the draft required surface based on the NC machining data using a tapered rotary machining tool having a predetermined taper surface with substantially the same diameter as the rotary machining tool, A draft surface is created in the draft required surface as a locus surface of the tapered surface of
By obtaining pressurizing the created has been the draft surface to the original shape of the original model, the model creating method characterized by creating a complete model is draft-faced model. The model creation method according to claim 4,
A model creation method of selecting the tapered rotary machining tool having a taper corresponding to the draft of the draft required surface and designating the type of tapered rotary machining tool in actual creation of the completed model. An original model representing a three-dimensional shape of a mold in which a fillet surface is not formed at a boundary portion between adjacent two surfaces adjacent to each other in a concave shape and a draft angle is not formed on the draft required surface connected to the boundary portion. Prepare
NC machining data is created as the original model is machined with a non-tapered rotary machining tool,
Based on the NC machining data, using a rotary machining tool with a tapered hemispherical tip having a predetermined taper surface substantially equal in diameter to the non-tapered rotary machining tool, a predetermined one of the boundary portions of the original model is determined. Alternatively, by performing a machining simulation for machining the draft required surface connected to the boundary portion at all the boundary portions, the draft surface is provided on the draft required surface, and the fillet connected to the draft surface is provided on the boundary portion. Forming a concave R surface as a surface, and adding the created concave R surface and draft angle surface to the original shape of the original model to create a completed model that is a draft surface model Model creation method.