JP3745526B2 - Roughing intermediate shape model generator for NC data creation - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for generating a rough machining intermediate shape model suitable for use in creating NC (numerical control) data used for rough machining in a CAM (computer-aided machining) system.
[0002]
[Prior art]
When manufacturing a die such as a forging die that cuts out from a block-shaped steel material, a material shape close to the final shape of the die is generally cut from the original block-shaped material shape by roughing. Finishing is performed later. In this specification, “material” refers to an object to be cut by a tool, and therefore, not only the original block shape of the cutting object but also the shape in the middle of processing is all “material shape”. .
[0003]
In the above roughing process, a square end mill is used to increase the amount of cutting per tool movement, and a Z value (in the height direction of the NC machine tool constituting the CAM system) is used to suppress fluctuations in the cutting load. In many cases, contour processing without movement of the coordinate value of the tool tip in a certain Z-axis direction is performed, but when creating NC data for the machining, at present, the NC data creator has shown in FIG. The initial shape of the material M as shown is grasped from a drawing or the like to instruct the CAM system. Then, as the roughing process proceeds, as shown in FIGS. 11B and 11C, the shape of the material M is changed by being scraped off by the square end mill T. The data creator sequentially grasps the changing material shape (intermediate shape), and the shape of the tool T and the material M in the tool fast-forward path connecting the tool paths in the air in the intermediate process of roughing The prevention of interference and prevention of uncut parts.
[0004]
In other words, the final shape of the mold is defined by drawing and modeling, but for intermediate processes where the shape has changed from the original material shape, the NC data creator grasps the intermediate shape of the material and examines the processing. Must proceed. At that time, the NC data creator must create NC data in consideration of the intermediate shape of the material so that there is no interference between the tool and the material shape in the tool rapid feed path, and there is no uncut material. Don't be.
[0005]
[Problems to be solved by the invention]
For this reason, conventionally, NC data creators have spent a great deal of man-hours for machining simulation and manual editing when creating NC data for rough machining. If the NC data creator is not accustomed to grasping the intermediate shape, the quality of the created NC data may not be sufficiently high.
[0006]
By the way, as a result of considering the material shape after the contour processing with a constant Z value, the inventor of the present application has come up with the idea that the material shape essentially becomes a combination of shapes corresponding to the sweep body.
[0007]
[Means for solving the problems and their functions and effects]
The present invention provides an apparatus that advantageously solves the problems of the prior art in view of the above points, and the rough machining intermediate shape model generation apparatus for NC data creation of the present invention is shown in the conceptual diagram of FIG. As shown in the figure, a plurality of partial intermediate shapes consisting of sweep bodies obtained by sweeping a sequence of points each having a constant Z value in the Z-axis direction are related to each other by a tree structure, and an intermediate shape model of the material is defined by a set of these partial intermediate shapes Intermediate shape model defining means 1 for determining a partial intermediate shape in an inclusive relationship or an intersecting relationship with respect to a machining range on a machining plane having a constant Z value from the set of partial intermediate shapes, and obtaining the obtained partial intermediate shape the two partial intermediate shape is divided by the processing plane, Rutotomoni not the upper side of the partial intermediate shapes of those portions intermediate shape is deformed on the basis of the machining range, on the above tree structure, said determined Seeking partial intermediate shape in the inclusion relation or cross relationship between the machining area by projecting onto the machining plane of the partial intermediate shape which is located in the upper layer of the partial intermediate shape, based on the obtained partial intermediate shape to the machining area The intermediate shape model is updated to update the intermediate shape model, and the intermediate shape model updating means 2 recombines the tree structure with the deformation of the partial intermediate shape.
[0008]
In such an apparatus, the intermediate shape model defining means 1 associates a plurality of partial intermediate shapes, each of which is a sweep body obtained by sweeping a point sequence having a constant Z value in the Z-axis direction, with a tree structure. An intermediate shape model of the material is defined by a set of shapes, and the intermediate shape model update unit 2 is in an inclusive relationship or a cross relationship with respect to a processing range on a processing plane having a constant Z value from the set of partial intermediate shapes. A partial intermediate shape is obtained , and the obtained partial intermediate shape is divided into two partial intermediate shapes by the machining plane, and the partial intermediate shape on the upper layer side of the partial intermediate shapes is deformed based on the processing range. Rutotomoni, wherein on the tree structure, the portion projecting to the machining plane in inclusion relation or cross relation with the working range of the partial intermediate shape which is located in an upper layer of the obtained partial intermediate shape Calculated between shape and the determined partial intermediate shape is deformed on the basis of the machining area updates the intermediate shape model, it rearranges the tree structure with the deformation of the partial intermediate shape.
[0009]
Therefore, according to this apparatus, the intermediate shape model of the material, which is a set of a plurality of partial intermediate shapes each consisting of sweep bodies, defined by the intermediate shape model defining means 1 in association with each other by the tree structure , Since the intermediate shape model updating means 2 updates the tree structure based on the contour processing range every time the processing is performed, the intermediate material shape that sequentially changes during the roughing processing is accurately and efficiently used. The NC data creator can easily grasp the intermediate shape of the material in the middle of machining when creating NC data for rough machining. Therefore, the NC data creation man-hour can be reduced. NC data creation quality can be improved.
[0010]
Moreover, according to the rough machining intermediate shape model generating apparatus for NC data creation of the present invention, the intermediate shape model updating means 2 is within the machining range on the machining plane having a constant Z value obtained from the set of partial intermediate shapes. On the other hand, the partial intermediate shape in an inclusive relationship or cross relationship is divided into two partial intermediate shapes by the processing plane, and the partial intermediate shape on the upper layer side of the partial intermediate shapes is deformed based on the processing range. Therefore, the partial intermediate shape can be deformed by a simple process.
[0011]
In the rough machining intermediate shape model generating apparatus for NC data creation according to the present invention, the intermediate shape model defining means 1 determines whether the object is inside or outside depending on which side it is positioned with respect to the direction in which the point sequence advances. The intermediate shape model can be defined with a simple data structure.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 2 is a block diagram showing an embodiment of the rough machining intermediate shape model generation apparatus for NC data creation according to the present invention, and FIG. 3A shows the rough machining intermediate shape for NC data creation of the embodiment. FIG. 3B is a perspective view illustrating a raw material shape in the middle of roughing that is a target of the model generation device, and FIG. 3B is a tree structure in which the device of the embodiment expresses a relationship between partial intermediate shapes in the raw material shape. It is explanatory drawing which shows.
[0013]
As shown in FIG. 2, the rough machining intermediate shape model generation apparatus of this embodiment uses an NC data creation computer that constitutes a normal CAM system so that the NC data creator can perform NC for rough machining in die machining. When creating data, it is configured by modifying the operation program of the NC data creation computer 3 so that the material shape in the middle of processing can be easily grasped. Intermediate shape model definition unit 4 and intermediate shape model update unit 5 as intermediate shape model update means 2.
[0014]
Here, the intermediate shape model definition unit 4 assumes that contour machining with a constant Z value, which is a coordinate value in the Z-axis direction (height direction) of the NC machine tool constituting the CAM system, is performed as shown in FIG. Is defined as a set of partial intermediate shapes A to E each of which is formed by sweeping a contour point sequence having a constant Z value in the direction in which the Z value decreases. The intermediate shape model composed of a set of A to E is expressed, and the relationship between the partial intermediate shapes A to E is expressed as a tree structure as shown in FIG. Here, the partial intermediate shapes B and C are included in the partial intermediate shape A because they are in the upper layer of the partial intermediate shape A (represented by being connected to the lower side on the tree structure). The partial intermediate shapes B and C are children of the partial intermediate shape A. Similarly, the partial intermediate shapes D and E are included in the partial intermediate shape C because they are in the upper layer of the partial intermediate shape C. The partial intermediate shape C is the parent of the partial intermediate shapes D and E, and the partial intermediate shapes D and E are It becomes a child of the partial intermediate shape C. Since the partial intermediate shapes B and C belong to the same Z value layer (represented side by side on the tree structure), they are not included in each other, and the partial intermediate shapes D and E are also the same. Since they belong to the Z value layer, they are siblings that are not included in each other.
[0015]
Hereinafter, the definition of the partial intermediate shape will be described in more detail. FIG. 4 shows an example of another material intermediate shape defined by the intermediate shape model defining unit 4. Here, the intermediate shape shown in FIG. 4A is defined as a set of partial intermediate shapes A to C. At the same time, the partial intermediate shape A is expressed as, for example, a point sequence AL having a constant Z value swept in the Z-axis direction by the amount a, and the partial intermediate shape B is a + b with a constant Z value. The point sequence BL is expressed as the partial intermediate shape B swept in the Z-axis direction by the height b of the partial intermediate shape B, and the partial intermediate shape C having the same height as the partial intermediate shape B is a + b with a constant Z value. The point sequence CL is expressed as a sweep of the partial intermediate shape C by the height b in the Z-axis direction.
[0016]
FIG. 5 shows a method of defining the inside and the outside of the partial intermediate shape defined by the intermediate shape model definition unit 4. Here, any of the moving directions of the point sequence having a constant Z value forming the top surface of the sweep body is shown. For example, in the illustrated example, the right side of the point sequence in the traveling direction is the inside of the shape, and the left side of the traveling direction is the outside of the shape. Therefore, the partial intermediate shapes A, B, and C obtained by sweeping a clockwise point sequence (referred to as “outer loop”) are convex, and the partial intermediate shape D obtained by sweeping a counterclockwise point sequence (referred to as “inner loop”). Becomes concave. A set of these partial intermediate shapes A to D becomes an intermediate shape of the entire material. On the other hand, each of the partial intermediate shapes A, B, C, and D is a single swept element with a closed Z value constant.
[0017]
As shown in FIG. 6, the partial intermediate shape of the inner loop (partial intermediate shapes F, G, and H in the figure) is always the partial intermediate shape of the outer loop (partial intermediate in the figure). Included in shape J). The partial intermediate shape of the outer loop may not include the partial intermediate shape of the inner loop, may include only one, or may include two or more as shown in the illustrated example.
[0018]
As shown in FIG. 7, each partial intermediate shape has a vertical, horizontal, and horizontal relationship in a tree structure. For example, regarding the partial intermediate shapes A, B, and C shown in FIG. 7A, as shown in FIG. 7B, the partial intermediate shapes B and C are included in the partial intermediate shape A, as shown in FIG. The partial intermediate shape A is a parent of the partial intermediate shapes B and C, and conversely, the partial intermediate shapes B and C are children of the partial intermediate shape A. In addition, since the left-right relationship is in each Z value layer, as shown in FIG. 7B, the Z value layer of the partial intermediate shape A exists only in the partial intermediate shape A, and other sibling relationships Although the partial intermediate shape does not exist, the Z-value layer of the partial intermediate shape B also has the partial intermediate shape C. Therefore, the partial intermediate shapes B and C have a sibling relationship that is not included in each other.
[0019]
However, as shown in FIG. 8A, the partial intermediate shape D of the inner loop included in the partial intermediate shape B of the outer loop is the same as that of FIG. As shown in FIG.
[0020]
Here, the intermediate shape model update unit 5 defines the intermediate shape model definition unit 4 every time the NC data creator sets a certain processing range in order to express the material shape during the processing. The intermediate shape model is updated by deforming the intermediate shape model. This update is performed based on the inclusion relationship and the cross relationship between the layer data having a predetermined Z value representing the set machining range and the intermediate shape model. At this time, since only a partial intermediate shape that is included or intersected with the processing range is selectively deformed using a tree structure, efficient processing is possible.
[0021]
FIG. 9 shows an example of the update of the intermediate shape model performed by the intermediate shape model update unit 5. In this example, as shown in FIG. 9A, from the set of partial intermediate shapes A, B, and C. For the intermediate shape model, a contour processing plane P is set in a Z-value layer having an intermediate height of the partial intermediate shape A, and a processing range W is set in a part of the processing plane P. The intermediate shape model is updated to the state after processing of W.
[0022]
In the original intermediate shape model tree structure shown in FIG. 9 (a), as shown in FIG. 9 (b), partial intermediate shapes B and C exist in the upper layer of the partial intermediate shape A. Thus, only the partial intermediate shape B is projected onto the processing plane P and has an inclusion relationship or an intersecting relationship with the processing range W. Therefore, here, as shown in FIG. 9A, the partial intermediate shape A that intersects the processing range W on the processing plane P is divided by the processing plane P to obtain two partial intermediate shapes Ad, D. Of the partial intermediate shapes, the portion intermediate shape Dd is obtained by deleting the portion that intersects with the processing range W from the partial intermediate shape D on the upper layer side and deforming the partial intermediate shape D, and further A portion where the projected portion from the intermediate shape B also intersects the machining range W is deleted, and the partial intermediate shape B is deformed to obtain a partial intermediate shape Bd. As a result, the updated intermediate shape model tree structure is rearranged from the original tree structure, and as shown in FIG. 9 (d), the partial intermediate shape Dd is added and the partial intermediate shapes A and B are respectively set to the partial intermediate structure. Changed to shapes Ad and Bd.
[0023]
FIG. 10 is a flowchart showing the processing procedure for updating the intermediate shape model performed by the intermediate shape model updating unit 5. Here, first, in step 11, the intermediate shape model is opened (read out from the storage device in the computer). Then, in step 12, a target Z value layer of the intermediate shape model is obtained from the Z value of the machining range to be updated, that is, the Z value of the machining plane where the machining range is located.
[0024]
Next, in step 13, the intersection between the partial intermediate shape of the target layer and the processing range and the inclusion relation are inspected, and in step 14 the partial intermediate that intersects the processing range or is included in the processing range from the inspection result. It is determined whether or not there is a shape. If there is no shape, the process proceeds to step 20 described later, but if there is, the process proceeds to step 15. In step 15, the partial intermediate shape that intersects or is included in the processing range (for example, the partial intermediate shape A in the example shown in FIG. 9) is modified and updated.
[0025]
After that, in step 16, the upper partial intermediate shape that is in a vertical relationship with the updated partial intermediate shape is searched by the above tree structure, and in step 17 whether there is a partial intermediate shape in the upper layer from the search result. If not, the process proceeds to step 20 described later. If there is, the process proceeds to step 18. Then, in step 18, the intersection of the upper partial intermediate shape (for example, partial intermediate shapes B and C in the example shown in FIG. 9) onto the processing plane and the processing range are inspected, and the following step 19 is inspected. Then, from the inspection result, it is determined whether there is any of the projections that intersects or is included in the processing range. If there is, the process returns to step 15 and the partial intermediate shape of the upper layer is determined. (For example, the partial intermediate shape B in the example shown in FIG. 9) is updated, and further upper layers are searched. If not, the process proceeds to step 20 to close the intermediate shape model (stored in a storage device in the computer) ).
[0026]
Thus, according to the rough machining intermediate shape model generation apparatus of this embodiment, every time the intermediate shape model is updated as described above, the computer displays the updated intermediate shape model on the screen of the screen display device. This makes it possible to accurately and efficiently represent the intermediate shape of the material that changes sequentially during the roughing process, making it easy for the NC data creator to create the intermediate shape of the material during the machining process when creating NC data for roughing. Therefore, the number of man-hours for creating NC data can be reduced, and the quality of creating NC data can be improved.
[0027]
Moreover, according to the rough machining intermediate shape model generation device of this embodiment, the intermediate shape model definition unit 3 distinguishes between the inside and the outside of the object depending on which side it is located with respect to the direction in which the point sequence proceeds. Intermediate shape models can be defined with a simple data structure.
[0028]
Further, according to the rough machining intermediate shape model generation device of this embodiment, the intermediate shape model update unit 5 determines the inclusion relation with respect to the machining range on the machining plane with a constant Z value obtained from the set of partial intermediate shapes. The partial intermediate shape in an intersecting relationship is divided into two partial intermediate shapes by the processing plane, and the partial intermediate shape on the upper layer side of the partial intermediate shapes is deformed based on the processing range. The partial intermediate shape can be deformed by processing.
[0029]
Although the present invention has been described based on the illustrated examples, the present invention is not limited to the above-described example. For example, the rough machining intermediate shape model generation apparatus of the present invention is configured by a computer separate from the NC data generation computer. You may do it.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram showing a configuration of a rough machining intermediate shape model generation apparatus for NC data creation according to the present invention.
FIG. 2 is a block diagram showing an embodiment of a rough machining intermediate shape model generation apparatus for NC data creation according to the present invention.
FIG. 3A is a perspective view illustrating a raw material shape in the middle of rough machining targeted by the rough machining intermediate shape model generation apparatus for NC data creation of the above embodiment, and FIG. It is explanatory drawing which shows the tree structure in which the apparatus of an example expresses the relationship between the partial intermediate shape in the raw material shape.
FIG. 4 is an explanatory diagram illustrating an example of another material intermediate shape defined by the intermediate shape model definition unit of the apparatus according to the embodiment.
FIG. 5 is an explanatory diagram showing an internal and external definition method of a partial intermediate shape defined by an intermediate shape model definition unit of the apparatus according to the embodiment.
FIG. 6 is an explanatory diagram showing properties of a partial intermediate shape defined by an intermediate shape model definition unit of the apparatus according to the embodiment.
FIG. 7 is an explanatory diagram illustrating an example of a tree structure representing a relationship between partial intermediate shapes defined by an intermediate shape model definition unit of the apparatus according to the embodiment.
FIG. 8 is an explanatory diagram showing another example of a tree structure representing a relationship between partial intermediate shapes defined by the intermediate shape model defining unit of the apparatus according to the embodiment.
FIG. 9 is an explanatory diagram illustrating a method in which the intermediate shape model update unit of the apparatus according to the embodiment updates the partial intermediate shape.
FIG. 10 is a flowchart illustrating a procedure in which an intermediate shape model update unit of the apparatus according to the embodiment updates a partial intermediate shape.
FIG. 11 is an explanatory view showing a change state of a material shape in roughing in contour line machining.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Intermediate shape model definition means 2 Intermediate shape model update means 3 NC data creation computer 4 Intermediate shape model definition portion 5 Intermediate shape model update portion

Claims (2)

An intermediate shape model in which a plurality of partial intermediate shapes composed of sweep bodies each obtained by sweeping a point sequence having a constant Z value in the Z-axis direction are related to each other by a tree structure, and an intermediate shape model of a material is defined by a set of these partial intermediate shapes Defining means (1);
From the set of partial intermediate shapes, a partial intermediate shape that is inclusive or intersecting with a machining range on a machining plane having a constant Z value is obtained , and the obtained partial intermediate shape is divided by the machining plane to obtain two a partial intermediate shape, Rutotomoni deform based on the upper layer side of the partial intermediate shapes of those portions intermediate shape to the machining area, on the above tree structure, partial intermediate which is located on an upper layer of the obtained partial intermediate shape and projected onto the machining plane seek partial intermediate shape in the inclusion relation or cross relation with the working range of the shape, updating said intermediate shape model the obtained partial intermediate shape is deformed on the basis of said machining area and the intermediate shape model updating means for rearranging said tree structure with the deformation of the partial intermediate shape and (2),
A rough machining intermediate shape model generation device for NC data creation comprising:   2. The rough machining intermediate shape for creating NC data according to claim 1, wherein the intermediate shape model defining means distinguishes between the inside and the outside of the object depending on which side it is positioned with respect to the direction in which the point sequence advances. Model generator.

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