JP2771361B2 - Rough cutter path generation system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutter path generating system for roughing, and more particularly to an N type for machining a three-dimensional compound curved surface.
The present invention relates to a roughing cutter path generation system used when generating C (numerical control) data.

[0002]

2. Description of the Related Art Conventionally, machining of a three-dimensional composite curved surface shape is performed by generating a roughing cutter path and a finishing cutter path. The difference between the roughing pass and the finishing pass is that the interval between the passes is wider in the roughing pass, and there is nothing when viewed only in one pass. In other words, for only one pass, both the roughing pass and the finishing pass are obtained by the finishing pass generation method.

[0003]

In the above-described conventional cutter path generating system for roughing, the amount of data of the cutter path is increased, and it takes time to transfer the NC data to the NC machining opportunity, or the data is converted into a dot sequence. Although the NC data is data for instructing a slight movement, a large amount of point sequence data for instructing the movement is generated, and there is a disadvantage that the tool is shaken during machining.

[0004]

SUMMARY OF THE INVENTION A roughing hatter path generating system according to the present invention comprises a roughing path interval storing a finishing path for finishing a three-dimensional complex curved surface shape. A roughing path selecting means for reading out the path by using a path offset means for generating a path obtained by translating the path selected for the roughing in the positive direction of the Z-axis by a rough machining tolerance; A rough machining path generating means for generating a rough machining path between a path and an original path to be offset, and a roughing path storage device for storing the rough machining path are provided.

[0005]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing the configuration of one embodiment of the present invention.

In FIG. 1, a finishing pass storage device 1 is shown.
Stores finishing path for processing a three-dimensional composite curved surface, for example, the path PS _1, PS ₂ ... PS _l Shown in FIG. 2 in advance. The path PS _i (i = 1, 2,..., L) is shown in FIG.
Are on one plane PL. Each pass P
S _i is A series of points P _k as shown in FIG. 8 (k ... 1,2, ..., n) is composed of. At this time, the plane PL on each path
Are parallel and the plane PL is perpendicular to the XY plane. That is, when each path is projected on the X, Y plane, FIG.
become that way.

Next, the roughing required path selecting means 2 in FIG.
The path PS _i (i = 1, 2) from the finishing path storage device 1
.. L) are sequentially read. First pass PS ₁ subject to the roughing pass, then determines the path PS ₃ farthest within the path distance for roughing as in FIG. Hereinafter, the same processing is repeated, and a path to be roughed is selected as shown in FIG.

As shown in FIG. 9, for each path selected by the path selection means 2 for the path offsetting means 3, a sequence of points P _k (k = 1, 2,... N) constituting the path. Is a point sequence Q _k that is translated in the positive direction of the Z-axis
(K = 1, 2,..., N).

Next, the roughing path generating means 4 generates a point sequence P _k (k = 1, 2,..., N) constituting the path before the offset and a point sequence Q _k (k = 1, _k ) constituting the path after the offset. 2 ... n)
And a rough machining pass is generated.

[0011] roughing path generation procedure, first the start point of the point P ₁ and the point Q _1, the midpoint S and roughing path as shown in FIG. 10. Next, a straight line L ₁ connecting the midpoint S and the point P ₂ ,
Obtains a straight line L ₂ connecting the _two, the roughing path generation target region surrounded by the straight line L ₁ and the straight line L ₂ as shown in FIG. 11, the line segment P
_It is checked whether _k Q _k (k = 2, 3, 4... n) is included in any part. All the line segments P ₂ Q ₂ are included.
The line segment P ₃ Q ₃ is partially included.

At this time, the straight line L ₁ and the line segment P ₃ Q ₃ have an intersection, but the straight line L ₂ and the line segment P ₃ Q ₃ have no intersection. Therefore, the straight line L ₂ a straight line again passing through the point Q ₃ included in the region between the straight line L ₁ and the straight line L ₂ at the end point of the middle point S and the line segment P ₃ Q _3. At this time, since the next line segment P ₄ Q ₄ is not included in the area between the straight lines L ₁ and L ₂ , the constituent points M of the point sequence of the rough machining path are generated on the line segment P ₃ Q _3. .

The point M constituting the point sequence of the roughing pass is represented by a line segment P ₃ Q
_The method of generating on the line ₃ uses the middle point of the line segment P ₃ Q ₃ included between the straight line L ₁ and the straight line L ₂ as the constituent point M. FIG.
(A) is an intersection of the straight line L ₁ and the line segment P ₃ Q ₃ when the I, the midpoint between the point I and the point Q ₃ is configured point M.

In the case of FIG. 12B, a straight line L ₁ and a line segment P
_j-1 Intersection with Q _j-1 is defined as I _1, and straight line L ₂ and line segment P _j-1
And when the intersection of the Q _j-1 and I _2, the midpoint between the point I ₁ and the point I ₂ is configured point M. Here the construction point M to the point M ₁ which Motoma'.

[0015] Next, as shown in FIG. 13, the straight line connecting the straight line L ₁ and to M ₁ and the point Q ₄ connecting the M ₁ and P ₄ and L _2.
As before, a line segment P _{k is} added to the area between the straight line L ₁ and the straight line L _2.
Check whether Q _k (k = 4, 5... N) is included. As shown in FIG. 14, the line segment Q _j Q _j , the line segment L ₁ and the straight line L
_If both have intersections, the process proceeds to the next P _j Q _j to check.

Further, as shown in FIG. 15, one of the end points of the line segment P _j Q _j is included in the region between the straight line L ₁ and the straight line L ₂ , and the other end point is other than the region between the straight line L ₁ and the straight line L _2. , A straight line L _k (k = 1 or 2) having no intersection with the line segment P _j Q _j is connected to the line segment P included in the region between the point M ₁ , the straight line L _1, and the straight line L _{2. j} Generate a straight line connecting Q _j and the end point,
Let the straight line be L _k (k = 1 or 2) again.
For Figure 19, and again a straight line L ₂ a straight line connecting the points M ₁ and the point Q _j. Next, a line segment P _j Q _j (j = 5, 6... N) between the two straight lines L ₁ and L ₂ is checked, and the same processing is repeated.

In the example of FIG. 13, two straight lines representing the area indicated by W ₃ are finally straight lines L ₁ and L ₂ . The last line segment included in this region is line segment P ₇ Q ₇ . A constituent point M of a rough processing pass point sequence is generated on a line segment P ₇ Q ₇ . The generation method is the same as described above. The above operations are repeated until the points constituting the rough processing pass point sequence are found on the last line segment P _n Q _{n as} shown in FIG. This point is referred to as E.

As a result, a middle point S → point M ₁ → point M ₂ → middle point E is generated as a rough machining pass as shown in FIG.
The roughing pass is stored in the roughing pass storage device 5 in the same manner as the storage of the finishing pass.

[0019]

As described above, in the system of the present invention, the data-compressed cutter path (point sequence) is placed between the finishing path and the path obtained by moving the finishing path in the positive direction along the Z-axis. ), The amount of NC data for rough machining can be reduced,
The NC data transfer time to the machine tool can be reduced.

Further, since the point sequence data for instructing a slight movement is also obtained, the tool does not shake during machining.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of a finishing pass for complex curved surface processing.

FIG. 3 is a diagram in which finishing paths for complex curved surface processing are projected on an XY plane.

FIG. 4 is a diagram illustrating selection of a roughing pass from a finishing pass.

FIG. 5 is a diagram in which a roughing pass is selected from a finishing pass and the pass is projected on an XY plane.

FIG. 6 is a diagram in which a roughing pass is selected from finishing passes.

FIG. 7 is a diagram showing that one path is on a plane.

FIG. 8 is a diagram showing that a path is composed of a sequence of points;

FIG. 9 is a diagram illustrating an example of an offset path.

FIG. 10 is a diagram illustrating an example of a first process of a rough machining pass;

FIG. 11 is a diagram showing a target area when a rough machining pass is obtained.

FIG. 12 is a diagram illustrating a relationship between an area for obtaining a rough machining pass, an offset pass, and an original pass.

FIG. 13 is a diagram illustrating an example of processing for obtaining a rough machining pass in the middle.

FIG. 14 is a diagram showing a relationship between an area for obtaining a rough machining pass, an offset pass, and an original pass.

FIG. 15 is a diagram showing a relationship between an area for obtaining a rough machining pass, an offset pass, and an original pass.

FIG. 16 is a diagram illustrating an example of a process of obtaining a final rough machining pass.

FIG. 17 is a diagram illustrating an example of a roughing pass.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Finishing path storage device 2 Roughing path selection means 3 Path offset means 4 Roughing path generation means 5 Roughing path storage device

Claims (1)

(57) [Claims] 1. A roughing path selecting means for reading a path at a roughing path interval from a finishing path storage device in which a finishing path for finishing a three-dimensional compound curved surface is stored; Path offset means for generating a path obtained by translating the path selected for use in the positive direction of the Z-axis by the rough processing tolerance, and forming a rough processing path between the offset path and the original path to be offset. A roughing cutter path generating system, comprising: a roughing path generating means for generating; and a roughing path storage device for storing the roughing path.