JPH0588738A - Path pattern deciding device for surface machining nc machine tool - Google Patents

Abstract

PURPOSE:To decide a path pattern which can evade the interference between a jig and a tool by deciding the presence or absence of the interference between the secondary machining area calculated from a selected path pattern and the position of the jig. CONSTITUTION:When the machining shape information 100 is inputted, the corresponding machining area shape pattern is selected and then a tool is selected. Then a primary machining area 102 is calculated and the presence or absence of interference is decided between the area 102 and a jig 104. If the presence of interference is confirmed, another machining shape pattern is selected. Then a path pattern of 'balanced wall 2 one way', for example, is selected when the absence of interference is confirmed. Then a secondary machining area 108 is calculated and the presence or absence of interference is decided between the area 108 and the jig 104. If the presence of interference is confirmed, the possible path patterns are repetitively selected. If no possible pattern is available, a cutting process is carried out again with the change of the machining area shape pattern. Then the area 108 is calculated with no interference caused to the jig 104, and a path pattern is decided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing machine for surface-working a work while moving a tool such as an end mill within a certain plane,
In particular, the present invention relates to an apparatus for determining a path pattern when moving a tool and a work relative to each other in order to control an NC machine tool for surface machining in which the relative movement of the tool and the work is numerically controlled.

[0002]

2. Description of the Related Art In the case of surface processing, it can be divided into a plurality of processing region shape patterns such as a shape pattern for processing the entire surface of a workpiece and a shape pattern for processing in a closed pocket shape, as shown in FIG. In addition, with respect to a specific processing region shape pattern, there are usually some path patterns capable of processing the shape pattern. For example, the "entire surface" processing area shape pattern can be processed by either the "one-way without parallel wall" path pattern or the "reciprocating without parallel wall" path pattern illustrated in FIG. Therefore, the applicant has means for storing a processing area shape pattern group and a path pattern group, and means for inputting processing shape information to be processed,
It proposes an apparatus that determines which processing area shape pattern is input when processing shape information is input, and further determines which path pattern can be used for processing. According to this, the path pattern is determined by inputting the processing shape information.

[0003]

However, according to the above-mentioned conventional technique, since the interference between the jig for fixing the work and the tool is not taken into consideration, when actually applied, the jig and the tool often interfere with each other. You are forced to modify the NC data. Therefore, the present invention develops a device that can determine a path pattern that can avoid interference with a jig.

[0004]

In order to solve the above problems, according to the present invention, a path pattern determining device, the concept of which is schematically shown in FIG. 1, that is, information indicating the position of a jig for fixing a workpiece. Means B for inputting, processing means A for inputting processing shape information indicating the position and shape of the processing surface area for processing the workpiece fixed by the jig, and storing various processing area shape pattern groups that can be processed. From the means C for preserving, the means E for prohibiting the selection of a specific machining area shape pattern, and the machining area shape pattern group stored in the means C for which the selection is not prohibited by means E,
Means D for selecting a machining area shape pattern corresponding to the machining shape information input by means A, means F for selecting a tool that can be machined with the machining area shape pattern selected by means D,
Based on the machining area shape pattern selected by the means D and the information on the tool selected by the means F, the contours other than the wall are expanded outward by a width obtained by multiplying the tool diameter by a constant to calculate the primary machining area. Means K, means M for judging the presence or absence of interference between the primary machining area calculated by means K and jig position input by means B, and machining area shape patterns for which the occurrence of interference is judged by means M. The specific processing area shape pattern selection prohibiting means E is used as a target P for prohibiting selection, a means G for storing a feasible path pattern group, a means I for prohibiting the selection of a specific path pattern, and a means G. A path pattern capable of processing the processing area shape pattern selected by the means D under the condition that interference does not occur is selected from the path pattern group whose selection is not prohibited by the means I in the present path pattern. Means H, means L for calculating the secondary machining area formed by the extension of the tool movement range when the path pattern selected by the means H, the secondary machining area calculated by the means L and the means B are input. Means M for judging the presence or absence of interference of jig positions, and path patterns for which the occurrence of interference is judged by the means M are stored in means P, means G for which selection is prohibited by the specific path pattern selection prohibiting means I. A path pattern determination device having a means J which uses a path pattern which is determined not to be prohibited by the means I and which is determined not to cause interference by the means M as a determined path pattern was created.

[0005]

According to the path pattern determining device having the above structure, the path pattern which does not interfere with the jig is determined. If a path pattern that causes interference with the jig is selected in the process of determining a path pattern that does not cause interference with the jig, a secondary processing area calculated based on the temporarily selected path pattern and Since the presence / absence of the interference with the jig position is determined by the means M, the interference between the jig and the tool is not found in advance and is not determined as the pass pattern. In this case, path pattern candidates are searched in sequence from other path patterns,
A path pattern is found that does not cause interference with the jig.

Prior to that, the processed area shape pattern is similarly searched. For example, if the area specified by the input machining shape information is also the “entire surface” machining area shape pattern and at the same time is the “parallel wall with zero wall thickness” machining area shape pattern, the path pattern is determined as “entire surface”. In contrast to the interference, when the path pattern is determined as "parallel wall", the interference may not occur. In this way, according to the path pattern determination device of the present invention, the processing area shape pattern that does not cause interference with the jig is determined, and the path pattern that can be processed and does not cause interference with the jig is determined. Of.

[0007]

FIG. 2 shows an example of the system configuration of an NC machine tool incorporating a path pattern determining device according to the present invention. In the figure, reference numeral 20 denotes a machine tool main body, and this main body 20 is provided with a movable base 25 which is movable in a horizontal plane by an X-axis motor 21 and a Y-axis motor 22. The work W is fixed to the movable table 25 by a jig 29. Reference numeral 24 in the drawing denotes an upper frame, on which the main shaft 26 is assembled so as to be rotated by a main shaft motor SM. The vertical height of the main shaft 26 is variable by the Z-axis motor 23. Incidentally, reference numeral 27 in the drawing denotes a tool magazine in which a plurality of tools are set. The selected tool is attached to the spindle 26 by the tool changer 28.

In this machine tool main body 20, the selected tool is attached to the spindle 26, and when the tool height is adjusted by the Z-axis motor 23, the tool is rotated by the spindle motor SM and the X-axis motor 21 and the Y-axis are rotated. The movable table 25 moves along the path pattern created by the shaft motor 22, and the workpiece W is surface-machined according to the path pattern.

Each of the motors 21, 22, 23 is X
It is controlled by the numerical controller 10 via the axis, Y axis, and Z axis servo units DUX, DUY, DUZ. Also the spindle motor SM
Is the spindle motor drive circuit 15 and the sequence controller 1
1 and the numerical control device 10. Numerical control device 10
The sequence controller 11 is connected to the computer 12. The computer 12 is a processing unit (MP
U) 12a, clock signal oscillation circuit 12b, ROM 12
c, RAM 12d, fixed disk 12e, interfaces 12f, 12g, 12h, etc. are connected to each other by a bus 12i. Interface 12
A keyboard 13 and a CRT display device 14 are connected to h, and an operator inputs machining shape information indicating the position and shape of the machining surface area of the work and information indicating the position of the jig 29 for fixing the work from the keyboard 13. You can do it. In this embodiment, the machining shape information input means A and the jig position information input means B are constituted by the keyboard 13.

The ROM 12c stores a program for executing the processing shown in FIG. In the process of FIG. 3, a step S2 executes a process of selecting a processing region shape pattern corresponding to the input processing shape information. In this embodiment, the ROM 12c stores ten types of processing area shape patterns shown in FIG. 4 as processing area shape patterns that can be processed by the machine tool 20. R in FIG. 4 indicates a processing region.

Each pattern is composed of a wall and a contour other than the wall. The wall indicates a boundary where the tool should not protrude from the contour, and the contour other than the wall indicates a boundary which does not prevent the tool from protruding. In the figure, the thick line shows the wall, and the thin line shows the outline that is not the wall.

Now, the machining shape information 10 as illustrated in FIG.
If 0 is input, the corresponding machining area shape pattern is “entire surface”, “ring”, “flat wall”,
A "parallel wall" shape pattern can be selected. "Full surface"
It is not necessary to explain that the above pattern corresponds to the shape of the processed shape information 100. Even with the "ring" pattern,
If the inner non-machined area is infinitely small, machined shape information 100
The shape of By setting the wall thickness to zero even in the pattern of "flat wall" and "parallel wall",
It can correspond to the shape of the processed shape information 100.
In the case of FIG. 6, if the pattern is such that the tool does not protrude from the contours 100a and 100b, it may be a parallel wall shape pattern.

On the other hand, according to the "closed pocket", since there are rounded corners, the contours 100a and 100b are formed.
While moving the tool so that it does not overflow the top 10
0c cannot be processed. Therefore "closed pocket"
Is not a shape pattern corresponding to the processed shape information 100. In step S2 of FIG. 2, one of the processing region shape patterns corresponding to the processing shape information thus input is selected. For convenience of explanation, it is assumed that the processing area shape pattern “entire surface” is selected at this stage.

When the machining area shape pattern is selected in step S2 of FIG. 3, the tool to be used next is selected in step S4. Here, a tool that can be machined and that can be machined in the shortest time is selected from factors such as the minimum machining width.
When the tool and the machining area shape pattern are selected, the primary machining area is calculated in step S5.

Here, the primary machining area is an area in which the contour other than the wall is expanded outward by a width obtained by multiplying the tool diameter by a constant as shown in FIG. When the contour is a wall, the tool does not protrude to the outside of the wall, so that the primary machining area is not expanded.
On the other hand, as for the contours other than the wall, as illustrated in the Q portion of FIG. 5, the tool may machine while sticking out of the contour, so that as the primary machining area, an area corresponding to this tool extension is set. It is calculated. As is clear from the example of FIG. 5Q, if the constant is 0.5 or more, the region left unprocessed can be eliminated. In this embodiment, a value of 0.6 is adopted. In the example illustrated in FIG. 7, the “entire surface” pattern in which all the contours are not walls is selected, and thus the primary processing region 102 is expanded in four directions as illustrated in FIG. 7.

When the primary processing area is calculated in step S5 of FIG. 3, it is then determined in step S6 whether or not there is interference with the jig. Here, the presence or absence of interference is determined by whether or not the jig positions 104a to 104f input from the keyboard 13 are in the primary processing area 102. In the case illustrated in FIG. 7, jig positions 104a, 104b, 104e, 104f
Is in the primary processing area 102. This corresponds to the interference between the tool and the jig when the tool is moved as shown by Q in FIG.

If it is determined in step S6 of FIG. 3 that interference has occurred, it is prohibited to reselect the pattern actually selected in step S2, in this case, the machining area shape pattern "entire surface" (step S8). ), Step S again
Execute 2. When this process is repeated, the selection progresses in the order of “entire surface” → interference → “ring” → interference → “flat wall” → interference → “parallel wall”.

When parallel walls are selected as shown in FIG.
In step S5, the primary processing area 106 shown in FIG. 8 is calculated. Here, since the contours 100a and 100b are walls, the primary processing region 106 does not expand left and right. Therefore, when the "parallel wall" pattern is selected in step S2, it is determined in step S6 that there is no interference with the jigs 104a to 104b, and the process proceeds to step S10.

In step S10, a pass pattern is selected. In this embodiment, the path pattern group illustrated in FIG. 5 is stored in the ROM 12c. For example, the path pattern "one-way without parallel walls" proceeds with the tool protruding from the contour as illustrated in FIG. 5, and progresses up to 15 mm away from the machining area and stops. This movement is repeated one way. In the case of "reciprocating without parallel wall", as described above, the tool moves in parallel when it exceeds 60% of the tool diameter from the work, and the traveling direction is reversed. However, the fulcrum and the end point start and end when the tool is 15 mm away from the machining area. This path pattern group is stored in the ROM 12c in association with the processing area shape pattern,
For example, "One-way without parallel walls" and "Round-trip without parallel walls" for "entire surface", "One-way parallel wall 1" and "Parallel wall 1" for "flat wall"
"Reciprocating" is stored in "parallel wall" and "parallel wall 2 one-way" and "parallel wall 2 reciprocating". Each path pattern is set so that it does not extend beyond the wall.

When step S10 in FIG. 3 is executed with the machining area shape pattern "parallel wall" selected, the path pattern "parallel wall 2 one way" is first selected. Next, in step S12, the secondary processing area 108 is calculated. Here, as shown in FIG. 5, according to the one-way path pattern, the fulcrum and the end point of each path are the processing area 100.
Since the tool is 15 mm away from the secondary machining area 108, the secondary machining area 108 is enlarged from the area 100 in the vertical direction by a width obtained by adding 15 mm to the tool diameter. After the secondary processing area is calculated in this manner, next, in step S14 of FIG. 3, it is determined whether or not there is interference with the tool. Here, the determination is made in exactly the same manner as the determination in step S6 of FIG. As shown in FIG. 9, when the path pattern of “parallel wall two one way” is selected, the secondary processing area 108 is located at the jig positions 104c and 104.
interfere with d. Therefore, in step S14 of FIG. 3, YES (interference occurs), and the selection of the path pattern is prohibited in step S16. Next, in step S18, it is determined whether or not there is a possible path pattern. In the case of this example, the path pattern “two parallel wall reciprocations” remains, and step S10 is executed again. On the other hand, when no pass pattern remains, the process returns to step S2 again and the possibility of avoiding interference with the jig is further searched by changing the processing region shape pattern. At this time, the tools may be replaced to increase the possibility of finding a path pattern that does not interfere.

Now, when step S10 is executed again,
Next, in step S12, the secondary processing area is calculated again.
Since the pattern of "two parallel wall reciprocations" is selected here, the calculated secondary machining area 110 extends downward by only 60% of the tool diameter, as shown in FIG. Therefore, the determination in step S14 is NO (no interference),
As a result, a path pattern that does not interfere with the jig is determined (step S20). In this way, according to this embodiment, a path pattern that does not interfere with the jig is determined.

In the case of the present embodiment, the keyboard 13 constitutes the machining shape information input means A and the jig position information input means B. Also, the computer 12, especially the ROM 12
The processing area shape pattern group storage means C and the path pattern group storage means G are constituted by c. Further, the computer 12 involved in the execution of step S2 causes the machining area shape pattern selection unit D to be executed, and the computer 12 involved in the execution of step S8 to be the specific machining area shape pattern selection prohibition means E to be the computer 12 involved in the execution of step S4. The tool selection means F, the computer 12 involved in the execution of step S10, the path pattern selection means H, the computer 12 involved in the execution of step S16 specify the path pattern selection prohibition means I involved in the execution of step S5. The computer 12 performs the primary machining area calculation means K, the computer 12 involved in the execution of step S12 the secondary machining area calculation means L, and the computer 12 involved in the execution of steps S6 and S14 determines the presence / absence of interference. But then the process from step S6 to step S8, and the process from steps S14 to S16, means P for the machining area shape pattern and path patterns of occurrence of interference with the selection prohibited is formed.

In the case of this embodiment, the presence or absence of interference with the jig is determined in steps S6 and S14. That is, the interference presence / absence determining means M is provided separately for the area pattern determining means and the pass pattern determining means. However, it is also possible to use a common processing flow for the processing procedure for determining the presence or absence of interference with the jig, and in this case, the determination for the area pattern and the pass pattern is performed by the same procedure. It goes without saying that the present invention can be implemented by any method.

[0024]

According to the path pattern determining apparatus of the present invention, it is possible to input the machining shape information and the jig position information,
It is possible to generate a surface processing path pattern that avoids the jig. Therefore, the creation of NC data is facilitated, and it is possible to prevent a situation in which the NC data is forced to be corrected.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing the concept of the present invention.

FIG. 2 is a diagram showing an example of a system configuration of a numerically controlled machine tool incorporating the path pattern determination device of one embodiment.

FIG. 3 is a diagram showing a processing procedure until a path pattern is determined.

FIG. 4 is a diagram illustrating an example of a stored processing area shape pattern group.

FIG. 5 is a diagram exemplifying a stored path pattern group.

FIG. 6 is a diagram illustrating a process of selecting a processing area shape pattern and a path pattern.

FIG. 7 is a diagram illustrating a process of selecting a processing area shape pattern and a path pattern.

FIG. 8 is a diagram illustrating a process of selecting a processing area shape pattern and a path pattern.

FIG. 9 is a diagram illustrating a process of selecting a processing area shape pattern and a path pattern.

FIG. 10 is a diagram illustrating a process of selecting a processing area shape pattern and a path pattern.

[Explanation of symbols]

 A machining shape information input means B jig position information input means C machining area shape pattern group storage means D machining area shape pattern selection means E specific machining area shape pattern selection prohibition means F tool selection means G path pattern group storage means H path pattern Selection means I Specific path pattern selection prohibition means J Path pattern determination means K Primary machining area calculation means L Secondary machining area calculation means M Interference presence / absence discrimination means N Surface machining NC machine tool

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Naoto Kawabe 1-1-1, Asahi-cho, Kariya city, Aichi Toyota Koki Co., Ltd. (72) Inventor Satoshi Jinnai 1-1-1, Asahi-cho, Kariya city, Aichi prefecture Toyota Inside Koki Co., Ltd.

Claims (1)

[Claims] 1. A path pattern determining device for an NC machine tool for surface machining, which performs machining while moving a tool relative to a workpiece in a plane, and means for inputting information indicating a position of a jig for fixing the workpiece. A means for inputting processing shape information indicating the position and shape of a processing surface area for processing a workpiece fixed by the jig, a means for storing various processing area shape pattern groups that can be processed, a specific processing A means for prohibiting the selection of the area shape pattern, and selecting a processing area shape pattern corresponding to the input processing shape information from the processing area shape pattern group which is not prohibited from being selected in the stored processing area shape pattern. Means, means for selecting a tool that can be machined with the selected machining area shape pattern, other than the wall based on the information about the selected machining area shape pattern and the selected tool Means for expanding the contour outward by a width obtained by multiplying the tool diameter by a constant to calculate a primary machining area, means for determining whether or not there is interference between the calculated primary machining area and the jig position input, Means for prohibiting the processing area shape pattern in which the occurrence of interference is determined by the specific processing area shape pattern selection prohibiting means, means for storing a feasible path pattern group, and prohibition for selecting a specific path pattern Means for selecting a path pattern capable of processing the processing area shape pattern selected under the condition that interference does not occur, out of the path pattern groups whose selection is not prohibited by the stored path patterns, is selected. Means for calculating the secondary machining area formed by the extension of the tool movement range when using the pass pattern, and the presence of interference between the calculated secondary machining area and the input jig position. Means for discriminating the occurrence of interference, and means for prohibiting the path pattern for which the occurrence of interference has been selected by the particular path pattern selection prohibition means, a path pattern that is stored, is not prohibited from being selected, and causes no interference And a means for determining a determined path pattern.