JPH03111908A - CAD/CAM equipment - Google Patents

Abstract

PURPOSE:To increase a processing speed by storing a Z coordinate in a curved face in a memory as an effective value and adopting the just preceeding effective Z coordinate to determine a Z coordinate outside the curved face. CONSTITUTION:After inputting the data of curves 20 to 22, 23 to 25, conditions such as a tool and a pass pattern necessary for working are inputted. The X and Y coordinates of a working pass are found out, and when the pass has been outputted to the whole range of th inputted working, the processing is ended. If the pass is not ended yet, the inside and outside of the curved face of the X and Y coordinates are decided, when the XY coordinates are included in a part 26, it is decided as the inside of the curved face, while a part 27 or 28 is decided as the outside. The Z coordinate of the point decided as the outside of the curved face is determined by adopting the effective Z coordinate stored immediately before the point. An NC code is added to the coordinates of the working pass determined by said procedure and the code-added working pass is outputted. Thereby even if an operator consciously defines a plane part parallel with an XY plane in a shape to be worked, the required shape can be worked and operator's load can be reduced.

Description

[Detailed description of the invention] [Industrial application field] This invention uses graphic data of the shape of the object to be processed.

The present invention relates to a CAD/CAM device that generates machining paths for NC machine tools.

[Conventional technology]

Figure 18 shows 2, for example, "Machine and Technology Vol. 36 No. 7.

CAD/CAM devices shown on pages 99 to 105. Although this example deals with a shape consisting of curved side surfaces and a top surface, the same method can be used even if the top surface is flat.

The object is a three-dimensional shape that has a plane parallel to the XY plane on the top surface and a curved side surface, as shown in Figure 4.
In machining in which the tool moves along the intersection line between this shape and a plane obtained by translating a plane perpendicular to the XY plane, as shown in the figure, (1) in Figure 18 is a means by which the operator defines the shape to be machined. , (2) means for controlling the XY coordinates of the machining path, (311 means for calculating the zfiIA mark on the curved surface defined in (1) corresponding to the XY coordinates in (2), (6)
is a machining path output means.

Next, the operation will be explained using FIGS. 4 to 11. Here, it is assumed that a machining path having a shape as shown in FIG. 4 is generated. 6 is a plan view of the shape of FIG. 4, and FIG. 7 is a front view.

First, in step (1) of FIG. 18, in order to define the curved surface portion shown in FIG. 8 of the shape of FIG. (23
) to (25) are input. Furthermore, in order to define the remaining plane portion shown in FIG. 9, the curve (21) in FIG. 6 and the curve 1i (24) in FIG. 7 are input.

Next, in step 2 (2), the XY coordinates of the machining path of the shape shown in FIG. 4 as shown in FIG. 1θ are calculated.

Next, in step 3 (3), the XY coordinates of the machining path obtained in step 2 (2) are determined whether the area of the shape shown in FIG. 4 belongs to the curved surface shown in FIG. 8 or the plane shown in FIG. The Z coordinate is calculated in the corresponding area.

Finally, in step 6 (6), the XY coordinates obtained in step 2 (2) and the Z coordinates obtained in step 3 (3) are output as a machining path.

By repeating the operations from step 2 (2) to step 6 (6), a machining path as shown in FIG. 5 is output.

[Problem to be solved by the invention]

Since the conventional CAD/CAM device is configured as described above, in step 1 (1) of FIG. 18, the operator is asked to define the plane portion shown in FIG. 9 of the shape to be processed in FIG. 4. Therefore, the music R (21) in FIG. 6 and the curve (24) in FIG. 7 are input. However, step 1 (
1) In order to define the part of the curved surface shown in Fig. 8, we use the curve (21) in Fig. 6 and the curve (21) in Fig. 7 as the upper sides of the two curved surfaces.
24) is input.

From the operator's perspective, it would be sufficient to input the curves in Figures 6 and 7 multiple times as data characterizing the shape of the workpiece in Figure 4, but it is necessary to input the same curve data twice. It feels like you're wasting your time because you have to enter information.

Further, in step 3 (3), the area to which the XY coordinates of the machining path belong is determined in three ways: whether it is a single curved surface, a plane, or neither. A general method of area inside/outside processing will be described in the section of the embodiments of the present invention, but if inside/outside range is performed for a plurality of areas, the internal processing speed will be correspondingly slow.

As mentioned above, in conventional equipment, XY
Even planes parallel to planes are treated as independent curved surfaces, which places an extra burden on the operator and internal processing.
There was also a problem that the processing speed became slow.

Particularly, when the shape to be processed is a combination of a plurality of shapes as shown in FIG. 4 as shown in FIG. 19.

This challenge will become more pronounced.

This invention was made to solve the above-mentioned problem, and when a part of the shape to be machined is a plane parallel to the , CAD/ that can output machining paths
The purpose is to obtain a CAM device.

[Means to solve the problem]

The CAD/CAM device of the present invention is equipped with an effective Z coordinate storage means and a Z coordinate determination means outside one curved surface.

[For production]

In this invention, the Z coordinates within the two curved surfaces are stored in the memory as valid values, and the Z coordinates outside the two curved surfaces are determined by employing the immediately preceding effective Z coordinates.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 16. FIG. 1 is a diagram showing the configuration of an embodiment of the present invention, in which (1) is a shape defining means that allows the operator to define a curved surface part of the shape to be machined, and (2) is a diagram showing the XY and Y directions of the machining path.
Means to control the coordinates, (3) is the XY determined in (2)
means for calculating the Z coordinate within the curved surface corresponding to the coordinate, (4)
is an effective Z coordinate storage means that stores the Z coordinate in (2) as the effective Z coordinate in the memory, and (5) stores the effective Z coordinate obtained immediately before as the Z coordinate outside the curved surface corresponding to the XY coordinate in (2). The adopted off-surface Z coordinate determining means (6) is a machining path output means that generates and outputs a machining path from the XY coordinates found in (2) and the Z coordinates found in (3) and (5). .

In addition, FIG. 2 is an electrical configuration diagram for realizing this invention, and in FIG. 2, (7) is a CPU that performs calculation processing, (
81 is a keyboard for inputting the shape of the object to be processed and processing conditions;
Input devices such as a mouse and function keys; (9) is a memory that stores values necessary for calculation processing such as the shape of the workpiece, processing conditions, and effective Z coordinate; a storage device such as a magnetic disk;
These are output devices such as CRTs, punchers, printers, plotters, etc. that output data using IOl.

Next, the operation of one embodiment of the present invention will be explained based on the flowchart of FIG. In addition.

It is assumed that a path as shown in FIG. 5 for processing a shape as shown in FIG. 4 is output. Here, FIG. 6 is a plan view of the shape of FIG. 4, and FIG. 7 is a front view of the shape of FIG. 4.

First, in step 110D of FIG. 3, in order to define the curved surface portion shown in FIG. 8 out of the shape of FIG.
0) to (22) and the data of curves (23) to (25) in FIG. 7 are input by the operator. Here, the remaining plane parts shown in FIG. 9 are not particularly defined.

Next, in Step 2■, input necessary conditions for machining, such as tools and bus patterns.

Next, in step 13 (13), only the XY coordinates of the machining bus as shown in FIG. 1O are determined. Next, step 14 (K
> to determine the end of the processing bus. Step 12 (If you have already given a pass to the entire range of processing input in shame, the process will end. If you have not finished the process.

In Step 15 (1), determine whether the XY coordinates obtained in Step 13■ are inside or outside the curved surface. .

Generally known methods for this determination include the following. First, as shown in FIG. 12, a set of covering circles covering a curved surface is generated, and a set of covering circles is generated to determine whether or not a given coordinate is inside or outside, as in PO.

Points that are not included in any of the circles are determined to be outside the curved surface.

If it is included in a certain circle, such as Pi or Pn, a set of covering circles with a smaller radius of the circle is generated, and 2, inside and outside are determined. Repeat this a finite number of times, and still have XY
If it is included, it is determined that it belongs to the curved surface part, as in Pi in FIG. 13, or that it exists very close to it, as in Pn. Next, in step 16 (υ), the Z coordinate of the point P belonging to the curved surface is calculated from the XY coordinates as shown in FIG. An example is the approximation of

below.

Show details. A three-dimensional curved surface is defined by a surface formula S(u,v) with parameters u and v.

(X, Y, Z)=(S(u,v),,S(u,v),,
S(u, v)z). For a given point p = (x, y), the XY coordinates (Xo, Yo) of the initial point 5 (Uo, Vo)
) performs convergence processing until it becomes sufficiently close.

Let F (u, v) = S (u, v) - P.

The Z value of P is approximated by finding an approximate solution (u, v) of F (u, v) = 0 and substituting it into S (u, v).

F (u, v) = (in fil vl y fur
vl). Take a value ε (epsilon) close to a certain O.

F (u+v) l ”= x (u, v)2+y (
u+v)''≧ε (lowercase letter for delta) Find u = u 1 δ U v = v 1 δV (lower case letter for delta) Update (u, v) and substitute it into F (u, v). This process Repeat a finite number of times.

IF(u,v)I”<C If so.

Since F (u, v)-1-0, this (u, v) is substituted into S (u, v), and the obtained Z value becomes an approximate value of the Z coordinate of P. Adopt this as the Z coordinate of P, and set the effective Z at step +7 (rD
Store as coordinates.

If it does not converge after a finite number of iterations, P becomes P in Figure 13.
Although it is near the curved surface like n, it is determined that it is outside the curved surface.

The points determined to be outside the curved surface in step 15a9 and step 16 (υ) are
) is used to determine the Z coordinate.

Specifically, the path changes as shown in FIG.

When the path is on a flat surface like point P2 in FIG. 15, the Z coordinate of point P1 at the boundary between the curved surface and the flat surface is stored as the previous effective Z coordinate. 16th until the path next enters the surface.
As shown in the figure, the Z of Pl is adopted as the Z coordinate. When the path goes outside the curved surface again like P4, the previous effective Z
The Z coordinate of P is stored as the coordinate. Until the path next enters the curved surface, the Z coordinate of P is used as shown in FIG. Here, Fig. 16 is an X whose path includes Fig. 15.
FIG. 3 is a cross-sectional view taken along a plane perpendicular to the Y plane.

In step 19 (1!l), an NC code is added to the coordinates of the machining path determined as described above, and the machining path is output.

By repeating the process from step 13 to step 19 (13) until it is determined that the pass is completed in step 14 (2), the machining pass is completed and NC data is created.

Incidentally, in the above embodiment, an example in which the shape is convex was shown.

Similarly, even with a concave shape as shown in FIG. 17, a machining path can be generated without independently defining a plane parallel to the XY plane.

〔Effect of the invention〕

As described above, in this invention, the operator does not have to consciously define the plane part parallel to the XY plane in the shape to be machined (although it is configured so that the desired shape can be machined, so the burden on the operator is reduced. This also has the effect of increasing the speed of internal processing.

[Brief explanation of drawings]

FIG. 1 shows a CAD/CAM according to an embodiment of the present invention.
2 is an electrical configuration diagram of the present invention and a conventional device, FIG. 3 is a flowchart showing the operation of an embodiment of the present invention, and FIG. 4 is a diagram showing the machining path generation target of this device. The figure which shows the example of a shape. FIG. 5 is a diagram showing an example of a machining path generated by this device, and FIG. 6 is a plan view of the shape of FIG. 4. Fig. 7 is a front view of the shape shown in Fig. 4, Fig. 8 is a diagram showing only the three-dimensional curved surface portion of the shape shown in Fig. 4, and Fig. 9 is a top view of the shape shown in Fig. 4. Fig. 10 is a plan view of an example of a machining path, Fig. 11 is a plan view showing the machining range of the shape of Fig. 4. Fig. 12 is a plan view showing only the plane part parallel to the XY plane of A plan view showing an example of points Pi, Pn, and Po inside and outside of a set of covering circles generated on a three-dimensional curved surface. Figure 14 shows that there is a point Pn that is outside the curved surface but very close to it. Figure 14 is a diagram showing that the corresponding point P on the three-dimensional curved surface is found from the XY drift.
Figure 5 is a diagram showing one of the paths for processing the shape. FIG. 16 is a cross-sectional view taken along a plane perpendicular to the XY plane including the path of the shape shown in FIG.
3 is a diagram showing points on the boundary between the plane part and the three-dimensional curved part, the first
Figure 7 is a diagram showing an example of a concave shape that is the target of machining path generation in the device B, Figure 18 is a conventional configuration diagram, and Figure 19 is an example of a shape to be machined in which the conventional problems are more noticeable. figure. In the figure, (1) is a shape definition means, (2) is a processing bus XY coordinate control means, and (3) is a curved surface Z coordinate calculation means. (4) is effective Z coordinate determining means, (5) is outside curved surface Z coordinate determining means, and (6) is machining path output means. In addition. The same symbols in the figures are the same. or a corresponding portion.

Claims (1)

[Claims] A three-dimensional shape consisting of a plane parallel to the XY plane and a curved surface is to be machined, and the curved part of the shape to be machined is defined for machining in which the tool moves along the intersection line of this shape and a plane perpendicular to the XY plane. Shape defining means and XY of the above machining path
A machining path XY coordinate control means for obtaining coordinates, an in-curved Z coordinate calculation means for calculating a Z coordinate in a curved surface corresponding to the machining path, and an effective Z coordinate that regards the in-curved Z coordinate as an effective Z coordinate and stores it in a memory. a coordinate storage means; an outside-curved Z coordinate determining means that employs an effective Z-coordinate on the curved surface obtained immediately before as the Z-coordinate outside the curved surface corresponding to the X-Y coordinate of the machining path; A CAD/CAM device comprising processing path output means for outputting Z coordinates.