JP3220744B2 - Flat part / standing wall part dividing method and recording medium - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention divides data of an envelope surface for controlling the movement of a tool into a flat portion and a standing wall portion when a tool having the same shape as a model is machined and manufactured using the tool. On how to do it.

[0002]

2. Description of the Related Art In order to automatically produce a product having the same shape as a model composed of a plurality of surfaces using a tool of an NC machine for simultaneous three-axis machining, a model obtained by CAD is used. In consideration of the shape data including the dimensional information of the tool to the shape data of the above, three-dimensional machining data is obtained in advance. And
The movement of the tool is controlled in accordance with the three-dimensional machining data to produce a model having the same shape as the model.

As a method for creating such three-dimensional processing data, the following method has been generally used. First, an offset surface is created for each surface constituting the model in consideration of the shape of the tool. In this case, the envelope surface drawn by the fixed point of the tool when the tool virtually contacts each surface of the model is the offset surface. For example, when the shape of the end portion for processing the tool is a hemisphere, an envelope plane drawn by a fixed point (center of the hemisphere) separated from each point on the model surface by a radius of the hemisphere is set as the offset plane. Then, the information on the offset plane becomes three-dimensional processing data for controlling the movement of the tool.

When an object having the same shape as the model is processed and manufactured, a flat portion (a portion substantially perpendicular to the direction in which the tool comes into contact with and separates from the workpiece) and a standing wall portion (a portion other than the flat portion). Are different from each other in the machining method using a tool.

FIG. 4 is a perspective view showing an example of a model M having a plurality of surfaces. In FIG. 4, the Z-axis direction is the direction in which the tool comes into contact with or separates from the workpiece, the portion of the surface substantially parallel to the XY plane is a flat portion, and the remaining portion is a standing wall portion. FIG. 5 (a diagram viewed from the X-axis direction) and FIG. 6 (a diagram viewed from the Z-axis direction) show division patterns of these flat portions and standing wall portions with respect to the model M shown in FIG. In FIG. 5, the region denoted by A indicates a flat portion, and the region denoted by B indicates a standing wall portion. In FIG. 6, the white region indicates the flat portion A, and the hatched region indicates the standing wall portion B. Shown respectively.

In the method for machining a flat portion, the height (position in the Z direction) of the tool is fixed, and the obtained offset surface (XY
A movement path at equal intervals is set on a plane parallel to the plane), and the movement of the tool is controlled according to the movement path. FIG. 7 shows an example of the movement of the tool T with respect to the workpiece N during the flat portion processing. On the other hand, in the processing method for the standing wall portion, information (contour path) connecting points at the same height (Z-direction position) on the offset plane is obtained, and the movement of the tool is controlled according to the obtained contour paths. FIG. 8 shows an example of movement of the tool T with respect to the workpiece N during the standing wall machining. As described above, by changing the processing method for each of the flat portion and the standing wall portion, an object having the same shape as the model can be accurately and efficiently manufactured.

[0007]

However, when it is not possible to discriminate which region is a flat portion or a standing wall portion in a model, it is impossible to switch the processing method in this way. Therefore, in the related art, a flat part and a standing wall part are separated by a worker who is involved in the processing and manufacturing process by visually determining the model. However, even if a model having a simple shape can determine a flat portion / standing wall portion, a model having a complicated shape has a large number of boundaries between them, making the determination difficult.

Since the actual movement of the tool is controlled by the information of the offset plane (envelope plane of the fixed point of the tool), which is three-dimensional machining data, it is important to divide the flat part / standing wall part in the offset plane. is there. There is a gap between the boundary between the flat portion / standing wall portion in the model and the boundary between the flat portion / standing wall portion on the offset plane in consideration of the shape of the tool. FIG.
FIG. 4 is a schematic diagram showing this shift. A solid line C indicates the surface of the model M, and a broken line D indicates an offset plane representing the fixed point locus of the tool T. As shown in FIG. 9, the boundary position C1 of the flat portion / standing wall portion in the model M and the boundary position D1 of the flat portion / standing wall portion on the offset plane D correspond to the radius of the hemispherical tip of the tool T. It is shifted by a corresponding amount. It is difficult for an operator to consider such a shift, and the operator can specify only the boundary in the model, and it is virtually impossible to specify the boundary of the flat portion / standing wall portion on the offset plane when machining with a tool. It was possible.

As described above, in the conventional method, in the case of a model having a complicated shape, it is not possible to divide a flat portion / standing wall portion on the offset plane, and even if it is performed, the result of the division is not accurate.

In the case where it is not possible to divide the area between the flat portion and the standing wall portion, either one of a processing method suitable for the flat portion and a processing method suitable for the standing wall portion is performed over the whole. Alternatively, both a processing method suitable for a flat portion and a processing method suitable for a standing wall portion are performed throughout.
The former method has a problem that the whole is not finished finely, and the latter method has a problem that useless movement of the tool is increased and machining efficiency is extremely poor. Under such circumstances, it has been desired to develop a method of dividing the flat portion and the standing wall portion on the offset surface.

The present invention has been made in view of such circumstances, and provides a flat / standing wall dividing method capable of easily and accurately dividing a flat and a standing wall on an offset surface. With the goal.

Another object of the present invention is to accurately and efficiently process and produce an object having the same shape as a model by accurately dividing a flat portion and a standing wall portion. An object of the present invention is to provide a method for dividing a wall.

It is still another object of the present invention to provide a recording medium on which a computer program capable of realizing the above-described flat / standing wall dividing method is recorded.

[0014]

According to the present invention, there is provided a method for dividing a flat portion / standing wall portion according to the present invention, in which a tool virtually contacts an object having the same shape as a model having a plurality of surfaces with each surface of the model. When processing the tool by repeatedly moving the tool in accordance with the data of the envelope drawn by the fixed point determined in relation to the tool, the envelope is moved to the envelope of the tool and the envelope. A method of dividing a flat portion, which is a portion in which the angle between the contact direction and the separation direction is from a right angle to a predetermined angle, and a standing wall portion, which is a portion other than the flat portion, based on the shape of the model. Specifying the position of the flat portion of the envelope surface in the approaching / separating direction, and calculating a plurality of paths connecting points having the same position in the approaching / separating direction in the data of the envelope surface. From the path, specified Extracting two adjacent paths with the position of the tan part interposed therebetween, and determining the part sandwiched by the extracted paths as a flat part and the other part as a standing wall part and dividing the same. Features.

In the recording medium according to the present invention, an object having the same shape as a model having a plurality of surfaces is drawn by a fixed point defined in relation to the tool when the tool virtually contacts each surface of the model. When processing by moving the tool according to the data of the envelope surface while repeatedly contacting and separating from the envelope surface,
The envelope surface, a flat portion that is a portion where the angle between it and the direction of contact and separation of the tool with respect to the envelope surface is in a range from a right angle to a predetermined angle, and a standing wall portion that is a portion other than the flat portion. A recording medium recording a computer program to be divided, wherein a step of specifying a position of the flat portion of the envelope surface in the contact / separation direction based on a shape of the model; and the contact / separation direction in data of the envelope surface. Calculating a plurality of paths connecting points having the same position, and selecting two paths adjacent to each other with the position of the designated flat portion between the calculated paths.
It is characterized by recording a computer program including a step of extracting a book path, and a step of determining and dividing a portion sandwiched between the extracted paths as a flat portion and another portion as a standing wall portion.

FIG. 1 is a schematic diagram showing the concept of the method of the present invention. First, for example, an operator reads the height (Z-axis direction position) of the flat portion of the model from the drawing of the model and specifies and inputs the height to the computer. The computer divides into a flat portion and a standing wall portion according to a software program as follows.

First, an offset surface is created by adding the size and shape (offset amount) of the tool to the height specified by the worker, and the height (Z-axis direction position) of the flat portion on the created offset surface is determined. FIG. 1A is a schematic view of an offset plane D viewed from the X-axis direction. Specifically, in the example shown in FIG. 1A, the heights of three flat portions a, b, and c are obtained.

Further, a plurality of contour paths connecting points having the same height on the offset plane D are calculated. FIG. 1 (b)
Shows the calculated contour path. Specifically, in the example shown in FIG. 1B, nine contour paths p1 to p9 are calculated. From these contour paths, a set of two contour paths that interpose the height of the flat portion on the offset plane D is extracted. Specifically, contour height paths p1 and p2 between the flat portion height a are extracted, and contour line paths p4 and p5 between the flat portion height b are extracted. Contour lines p8 and p9 between the part height c are extracted.

A region sandwiched between the two extracted contour paths is defined as a flat portion. In addition, a region other than the flat portion is defined as a standing wall portion. Therefore, specifically, between p1 and p2, p4,
A portion between p5 and between p8 and p9 is determined as a flat portion, and a portion between p2 and p4 and between p5 and p8 are determined as a standing wall portion.

When the flat portion and the standing wall portion are divided as described above, all the portions of the offset surface for controlling the movement of the tool can be necessarily divided into either the flat portion or the standing wall portion. Thus, accurate division can be realized without overlapping the flat portion and the standing wall portion.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the drawings showing the embodiments.

FIG. 2 is a flowchart showing the procedure of the flat / standing wall dividing method according to the present invention. In FIG.
Only steps S1 and S2 are processes performed by the worker, and the remaining processes in steps S3 to S7 are processes realized by software in a computer. First, model information and tool information are input (step S1). The information of the model includes information such as a processing area, a surface on which processing is performed, and processing conditions. Further, the information on the tool includes information such as the size and shape of the end portion of the tool that actually performs the processing in contact with the processing surface.

Next, the worker reads the height of the flat portion of the model with reference to the model drawing and inputs the height to the computer (step S2). The value obtained by adding the offset amount of the tool to be used (for example, the radius of the spherical portion when the end portion of the tool in contact with the processing surface is spherical) to the read height of the flat portion is referred to as the flat portion of the offset surface. (Step S3).

A point at the same height in a plurality of offset planes (for example, a point at the same height in the center of the hemisphere if the end of the tool in contact with the processing surface is hemispherical)
To calculate a plurality of contour paths connecting
4). Next, two pieces 1 that set the height of the specified flat part between
A set of contour paths is extracted from the calculated contour paths by the same number of sets as the number of designated flat part heights (step S5).

The extracted contour path is defined as the boundary between the flat portion and the standing wall portion, and the region sandwiched between the pair of extracted contour lines is determined as the flat portion (step S6). Then, the region other than the flat portion, that is, all the regions not determined as the flat portion, is determined as the standing wall portion (step S7).

In step S2, the operator does not read the height of the flat part of the model with reference to the model drawing, but uses an analysis command of the modeling unit for recognizing the shape of the model, and an arbitrary command on the surface of the model. Since it is possible to know the coordinate value of the point, the height of the flat portion of the model may be obtained from the coordinate value of the substantially flat portion of the model using this.

After dividing the flat portion and the standing wall portion as described above, the height component (Z-axis component) of the boundary information is removed to obtain planar (XY plane) region information. Then, processing data is created using the area information. That is, for the area corresponding to the flat part, the processing data is created by setting the equally-spaced movement paths on the offset plane, and for the area corresponding to the standing wall part, a plurality of contour paths are set. Create machining data.

Using a different processing method for the flat portion and the standing wall portion, the tool is moved in accordance with the processing data created in this way to perform processing on the object to be processed, and an object having the same shape as the model is produced. . FIG. 3 shows the offset surface as a flat portion A.
And the standing wall portion B, the tool T is moved relative to the workpiece N. In the flat part A, processing is performed by projecting equally-spaced paths on the XY plane, for example, and a part close to the plane is finished. On the other hand, in the standing wall portion B, a contour line processing is performed to finish a portion close to the standing wall.

In the flat portion A and the standing wall portion B, it is only necessary to perform only the processing corresponding to each, so that there is no waste in the processing. In addition, since it can be accurately divided into the flat portion A and the standing wall portion B, each portion can be finely finished.

[0030]

As described above, according to the present invention, when a tool is moved in accordance with three-dimensional machining data to machine and produce an object having the same shape as a model, a flat portion and a standing wall portion are easily and accurately divided. It is possible to

Further, according to the present invention, the flat portion and the standing wall portion can be accurately separated from each other without any gaps or overlaps. An object having the same shape as described above can be produced with high accuracy and efficiency.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a concept of an embodiment of a flat part / standing wall part dividing method of the present invention.

FIG. 2 is a flowchart showing a procedure of a flat portion / standing wall portion dividing method of the present invention.

FIG. 3 is a schematic diagram showing a state in which an object having the same shape as a model using a tool is processed and manufactured.

FIG. 4 is a perspective view showing an example of a model having a plurality of surfaces.

FIG. 5 is a front view showing the model shown in FIG. 4 classified into a flat portion and a standing wall portion.

FIG. 6 is a plan view showing the model shown in FIG. 4 classified into a flat portion and a standing wall portion.

FIG. 7 is a schematic view showing an example of a movement of a tool in flat portion processing.

FIG. 8 is a schematic view showing an example of a tool movement in vertical wall machining.

FIG. 9 is a schematic diagram illustrating a state in which a boundary position of a flat portion / standing wall portion differs between a model and an offset surface.

[Explanation of symbols]

 A Flat portion B Standing wall portion C Model surface D Offset surface (envelope surface) M Model N Workpiece T Tool a, b, c Height of flat portion p1 to p9 Contour line path

Continuation of front page (56) References JP-A-7-295621 (JP, A) JP-A-7-84621 (JP, A) JP-A-6-19527 (JP, A) (58) Fields investigated (Int) .Cl. ⁷ , DB name) G05B 19/18-19/46 B23Q 15/00-15/28 G06F 17/50

Claims (2)

(57) [Claims] 1. An object having the same shape as a model having a plurality of surfaces is formed on the object according to data of an envelope surface drawn by a fixed point defined in relation to the tool when the tool virtually contacts each surface of the model. When the tool is moved and machined while being repeatedly moved toward and away from the envelope surface, an angle between the envelope surface and the direction in which the tool approaches and separates from the envelope surface is in a range from a right angle to a predetermined angle. A method of dividing into a flat portion that is a portion and a standing wall portion that is a portion other than the flat portion,
Specifying the position of the flat portion of the envelope surface in the approaching / separating direction based on the shape of the model; and calculating a plurality of paths connecting points at which the positions in the approaching / separating direction in the data of the envelope surface are equal. And extracting two adjacent paths from the calculated path with the specified position of the flat part in between. The part sandwiched between the extracted paths is a flat part, and the other part is a standing wall. Deciding a part and dividing the flat part / standing wall part. 2. An object having the same shape as a model having a plurality of surfaces is formed by enclosing an object according to data of an envelope drawn by a fixed point defined in relation to the tool when the tool virtually contacts each surface of the model. When the tool is moved and machined while being repeatedly moved toward and away from the envelope surface, an angle between the envelope surface and the direction in which the tool approaches and separates from the envelope surface is in a range from a right angle to a predetermined angle. A recording medium storing a computer program for dividing a flat portion that is a portion and a standing wall portion that is a portion other than the flat portion, wherein the approach and separation directions of the flat portion of the envelope surface are based on the shape of the model. A step of specifying a position in; a step of calculating a plurality of paths connecting points at which the positions in the approaching and separating directions in the data of the envelope surface are equal; and calculating a position of the specified flat portion from the calculated paths. In between Computer program including the steps of extracting two paths adjacent to each other, and determining the portion sandwiched by the extracted paths as a flat portion and the other portion as a standing wall portion and dividing the computer program. Characteristic recording medium.