JPH01257546A - Rough machining nc data producing method - Google Patents

Abstract

PURPOSE:To shorten the time for producing rough machining NC data by split ting a three-dimensional curved face into many micro tetragons constituted of a plurality of interpolation points thereafter obtaining a cubic or a rectangu lar parallele pipied block surrounding the tetragons and positioning a tool. CONSTITUTION:A three-dimensional curved face 20 is split into many micro tetragons constituted of a plurality of interpolation points, then a cubic or rectangular parallelepiped block B surrounding the tetragons is obtained. Then paths for splitting XY plane of a coarse member 40 representing the three- dimensional curved face 20 prior to machining in X and Y directions with predetermined interval, and a tool T is positioned at a cross point P. If there is one block B when the tool T is viewed on the XY plane, maximum value in Z-direction is employed as a co-ordinate value in Z-direction, while when there are a plurality of blocks B, maximum one is employed as the co-ordinate value in Z-direction. By such arrangement, time necessary for forming rough machining NC data can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for creating rough machining NC data for rough machining of three-dimensional curved surfaces using a numerically controlled machine tool.

<Conventional technology> For example, when performing rough machining of a mold with a three-dimensional curved surface from the material shape (rough machining is necessary because machining the finished shape immediately from the material shape will result in a large amount of machining and take a long time to cut, etc.) ), the surface is created on the screen of the minicomputer using the cross-sectional shape data of the three-dimensional curved surface that defines the finished shape inputted from the part program or personal computer, and the operator can While displaying the 3D curved surface shape or the plan view, side view, etc. of this 3D curved surface shape, the state of interference between the tool and the workpiece is determined empirically, and the NC data for rough machining of the 3D curved surface is manually generated. NC data for rough machining is created by calculating each interpolation of interpolation data for creating a three-dimensional curved surface.

<Problem to be solved by the invention> However, in the method of manually determining the interference between the tool and the workpiece and creating NC data for rough machining, There was a problem in that it was very time consuming because it was done manually.

In addition, in the method of creating NC data by calculation from each interpolation point of interpolation data that creates a three-dimensional surface, there are a large number of interpolation points because calculation is performed on a free-form surface called a three-dimensional surface. The method of reading and calculating the interpolation points one by one has a problem in that it takes a lot of calculation time.

<Means for Solving the Problems> The present invention divides a three-dimensional curved surface into a large number of minute quadrilaterals made up of a plurality of interpolation points, and divides each minute block consisting of a cube or rectangular parallelepiped surrounding this minute quadrilateral. Find each quadrilateral, then position the tool on a path that divides the three-dimensional curved surface into predetermined intervals on the X-Y plane, and when this tool is viewed on the X-Y plane, this] - Y If only one block is included in the plane, the maximum value in the Z direction of the tool center axis direction of the block is taken as the coordinate position of the tool in two directions, and multiple blocks are included in the X-Y plane of the tool positioned on the path. Z among these blocks if it contains a block of
This method is characterized in that the maximum value in the direction is taken as the coordinate position in the Z direction, and NC data is created.

<Operation> A three-dimensional curved surface is divided into a large number of micro quadrilaterals (hereinafter, these micro quadrilaterals are referred to as batches) made up of multiple interpolation points, and for each batch, a rectangular parallelepiped or cube surrounding the batch is divided. Next, find paths that divide the X-Y plane of the material shape before creating the three-dimensional curved surface in the X and Y directions at predetermined intervals, and place the tool on the intersection of these paths. Position it, and at this time
The coordinates in the Y direction are the X and Y coordinates, and in the Z direction (height direction), when the tool is viewed on the X-Y plane on the intersection point, there is one block in the X-Y plane. , the maximum value in the Z direction of this block is Z
It is a coordinate value in the direction (height direction), and when multiple blocks are included in this XY plane, Z among these multiple blocks is
The maximum direction is taken as the coordinate value in the Z direction.

<Example> Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a conceptual diagram when a three-dimensional curved surface 20 is created by cutting a material 40 with a rough machining tool T (hereinafter referred to as tool T).

B is a block surrounding the three-dimensional curved surface 20, P (
m, n, Zb) are positions where the tool T is positioned during rough machining.

In FIG. 2, 10 is a computer forming the main body of the automatic programming device. This computer 10 is connected not only to a magnetic disk device 12 but also to a display 13 and a keyboard 14 via an interface IFI.
, a personal computer 17 are connected, and a printer 15 and a tape puncher 16 are connected via an interface IF2.
is connected.

Next, using the apparatus configured as described above, the operator inputs in advance a part program defining cross-sectional shape data for creating the three-dimensional curved surface 20 using the keyboard 14 and stores it in the magnetic disk drive 12, and then performs rough machining. The operation of the computer 10 when creating NC data will be explained with reference to flowcharts shown in FIGS. 1, 3 to 7, and 8.

First, in step 100, a part program that defines a cross-sectional shape stored in the magnetic disk device 12 is read. In step 101, three-dimensional screen creation data for creating the three-dimensional curved surface 20 is created based on the cross-sectional shape data read in step 100.

In step 102, out of the three-dimensional surface generation data created in step 101, a punch is created using the three-dimensional surface generation data, in which one unit is a collection of nine interpolation points among the interpolation points constituting this three-dimensional surface 20. It is created on the entire created three-dimensional curved surface 20. This patch is 21 in Figure 3.
As shown in , there are nine interpolation points H1l on the three-dimensional curved surface 20.
~H33.

In step 103, a block B surrounding the plurality of patches 21 created in step 102 is determined.

This block B, as shown in FIG.
, the maximum value and the minimum value in each direction of Y and X directions.

In step 104, the state of interference between each block B and the tool T determined in step 103 is checked.

In the next step 105, NC data is created from the positioning position data of the tool T determined in step 104, and is stored in the magnetic disk device 12.

Here, the details of the interference state check in step 104 are shown in FIG.

In step 200, a process for determining the position of the tool T is performed. In this process, as shown in FIG.
- Distance L in the X and Y directions on the Y plane (tool radius r≦L<
2r), and the intersection of the line segments in the X and Y directions is determined by the positioning position data P(1,1) to P(m) of the tool T on the XY plane.

n).

In step 201, positioning position data P(n+) of all the tools T calculated in step 200 is calculated.

a counter m for making it possible to read out n) in sequence;

Set 1 to each of n.

In the next step 202, as shown in FIGS. 6(a) and 6(b), interference between the tool T and the block B in the XY plane is determined.

In this step 202, as shown in FIG. 6(a),
It is determined whether the tool T as seen on the X-Y plane is included in the block B as seen on the X-Y plane. When this determination is included, it is determined that the tool T and the plurality of blocks B do not interfere, and the process moves to the next step 203.

In this step 203, as shown in FIG. 7(a),
Positioning position data P(m
, n) is the maximum value zb in the X direction of block B2 corresponding to tool T positioning coordinate position data T(XIYIZ) =
It is stored in the magnetic disk device 12 as P(m, n, Zb).

If the determination in step 202 is included, the process shown in FIG. 6 (
As shown in b), it is determined that a plurality of blocks B are included within the circle that is the outline of the tool T viewed on the XY plane.

In this step 204, as shown in FIG. 7(b),
The maximum value in the X direction of blocks B2 and B3 included in the circle that is the outline of the tool T on the XY plane shown in FIG. 6(b) is determined. In this case, Zmax of block B3 is the maximum value in the X direction, and the positioning coordinate position data of tool T is T(X, Y, Z) = P(m).

n, ZIIlax) in the magnetic disk device 12.

Steps 206 to 209 perform a process of incrementing the counters m and n, respectively, so that the positioning position data of the tool T on the XY plane P(m, n) can be sequentially output.

When the above steps 200 to 209 are completed, the process moves to step 105, and the positioning position data P(X, Y, Z) of the tool T stored in the magnetic disk device 12 is calculated.
NC data is created from scratch and stored in the magnetic disk device 12.

By processing steps 100 to 105 above,
NC data for rough machining can be created.

<Effects of the Invention> As described above, in the present invention, a three-dimensional curved surface is divided into a large number of minute quadrilaterals made up of a plurality of interpolation points, and blocks made of cubes or rectangular parallelepipeds surrounding these minute quadrilaterals are created. Then, the tool is positioned on a path that divides the three-dimensional curved surface into predetermined intervals on the X-Y plane, and when this tool is viewed on the X-Y plane, - If only one block is included in the Y plane, the maximum value in the Z direction of the tool center axis direction of the block is taken as the Z direction coordinate position of the tool, and the tool positioned on the path is defined in the XY plane. When a block contains multiple blocks, the maximum value in the Z direction of these multiple blocks is used as the coordinate position in two directions to create NC data, which can reduce the time required to create NC data for rough machining. There are advantages that can be achieved.

Another advantage is that even a person with no experience in rough machining can easily create NC data for rough machining.

[Brief explanation of the drawing]

Figure 1 is a conceptual diagram of the rough machining of the present invention, Figure 2 is a block diagram showing the hardware configuration of the embodiment device, Figure 3 is a diagram for explaining patches, and Figure 4 is for explaining blocks. Figure 5 is a diagram for explaining the positioning position of the tool, Figures 6 (a) and (b) are diagrams for explaining the determination of the interference state between the tool and the block, and Figure 7 is a diagram for explaining the positioning of the tool. Diagram 8 for explaining interference between a tool and a block in the axial direction
9 are flowcharts for explaining the operation of the CPU. 10... CPU, 12... Magnetic disk mounting, 13
...Display device, 14...Keyboard. Patent jaw person Toyota Machinery Co., Ltd. Figure 2 Figure 5 P (m, n) / /

Claims (1)

[Claims] Divide at least a pair of opposing boundary lines into an equal number of shape elements consisting of circular arcs or line segments, calculate and find interpolation points on the boundary lines, and connect the interpolation points on the opposing boundary lines with an interpolation curve. In a three-dimensional curved surface NC data creation method for creating NC data for processing a three-dimensional curved surface surrounded by four boundary curves, the intersection with a plurality of interpolation curves is set as an interpolation point of the three-dimensional curved surface. Divide into a large number of small quadrilaterals made up of a plurality of interpolation points, find a block consisting of a cube or a rectangular parallelepiped that surrounds this small quadrilateral, and then convert the three-dimensional curved surface into X-Y The tool is positioned on a path divided at predetermined intervals on a plane, and when this tool is viewed on an X-Y plane, if only one block is included in this X-Y plane, the tool center axis of the block The maximum value in the Z direction of the direction is taken as the Z direction coordinate position of the tool, and if the tool positioned on the path includes a plurality of blocks in the XY plane, the Z direction of the plurality of blocks is A method for creating NC data for rough machining, characterized in that NC data is created using a maximum value as a coordinate position in the Z direction.