JPS60191741A - Tool-passage control - Google Patents

Abstract

PURPOSE:To automatically work a convex part by setting the position of a range passage over the position of the first boundary point, in the tool-passage control in an NC apparatus. CONSTITUTION:In order to permit the smooth working between two curves on the sectional surface of a three-dimensional free curved surface in NC work, the range passing speed is set to rapid traverse beforehand, and a range passage APP is set over the first boundary point B1, and after a tool TL reaches the boundary point B1, the tool is shifted to the escape point EP in the vicinity of the boundary point B1, and after the second boundary point B2 is calculated, the tool is shifted to the passage APP through rapid traverse, and then shifted over the boundary point B2 through over the passage APP, and then the tool is positioned at the boundary point B2 through rapid traverse. Through this method, the working for a convex part PR can be performed automatically on passing the range, and the formation of cutter mark on a worked article is prevented.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a tool path control method for a numerical control device, and in particular calculates a tool path using data specifying a curved surface, and controls the tool path obtained by the calculation. The present invention relates to a tool path control method using a numerical control device for machining a curved surface by immediately moving a tool along a path and then repeating tool path calculation processing and tool movement control processing.

Background Art A three-dimensional free-form surface is generally represented by a plurality of cross-sectional curves on a design drawing, and shape data between one cross-sectional curve and the next is not specified. However, in numerically controlled machining, it is required to process so that the two cross-sectional curves are smoothly connected, even though the intermediate shape is not provided. Regarding you,
In other words, a curved surface between the above two cross-sectional curves is generated from data of the cross-sectional curve, an NC tape is created using data regarding the generated curved surface, and processing is performed according to instructions from the NC tape. It means that there must be. For this purpose, a plurality of intermediate cross sections are generated according to a predetermined rule from data specifying several cross sections and cross-sectional curves of a three-dimensional curved body, and the cross-sectional curve (intermediate cross-sectional curve) of the curved surface body using the intermediate cross sections is estimated. A method of generating a curved surface of a three-dimensional curved body using a plurality of generated intermediate cross-sectional curves has been developed and put into practical use. As shown in FIG. 1, the method B is based on cross-sectional curves 11a and 12a and third and fourth cross-sections (not shown) when the curved surface 10 is cut through the first and second cross-sections (not shown). Cross-sectional curve 21 when cutting a curved surface
a, 22a, a large number of point sequences (black circles in FIG. 1) lines 13a-1, 13a-2, . . . 13 on the curved surface
Create an NC tape that moves the tool sequentially along each intermediate cross-sectional curve from a to n, input the NC tape into a numerical control device, and move the tool along the intermediate cross-sectional curve to create a curved surface. It is used for processing. Incidentally, in the above description, an NC tape is prepared in advance off-line, and numerical control is performed using the NC tape.

By the way, the tool path (position data of the point indicated by the black circle in Fig. 1) is calculated from the data that specifies the most recent curved surface, and the tool is immediately moved from the current position to the newly calculated point using the calculated position data. There is a need for a numerical control device that processes curved surfaces by moving the tool and repeating calculation of new points in the method and control of tool movement at will. The problem with such online numerical control is (1) a convex part exists in a predetermined area 30 (see Figure 1) on a curved surface, and the tool is moved over the convex part to move out of the area. (2) or the next Ena tool outside the area along the convex part is moved by cutting feed, and (3) I11 is placed in area 30. This is a case of moving to the next point outside the area while processing "j" (see Fig. 3). Point B will be explained below.

Now, if the tool reaches the first boundary point B1 of the region 30 along the intermediate cross-sectional curve 13a-i in FIG. 1, the tool stops rotating at the first boundary point B1. do.

After that, the numerical control device controls the intermediate section 1111 Xu, 13
The tool path (position data of points indicated by white circles) in the area 30 is sequentially calculated along the line a-i until the tool path exits the area 30. Then, the first point B2 that passed through area 30
(Second boundary point) is reached, the tool that has been stopped tL is then moved by rapid traverse or cutting feed along the path shown by the thin line in Figure 2 to the second boundary point B2, or the tool is moved along the path shown by the thin line in Figure 3. Move it to the second boundary point +32 while cutting the groove along. By the way, it takes a considerable amount of time to calculate the coordinate values of a point on a curved surface (white circle in Figure 1), so it takes a considerable amount of time to calculate the coordinate values of a point on a curved surface (white circle in Figure 1), so it takes a long time to calculate the coordinate values of a point on a curved surface (white circle in Figure 1). It takes a considerable amount of time. As a result, the machine remains stationary for a long period of time while rotating, resulting in cutter marks or gouges on the machined parts, and in the case of woodwork, the woodwork may become scorched or burnt. white.

゛〈Object of the Invention〉 The purpose of the present invention is to prevent cutter marks from being formed on the machined part even when a predetermined region does not exist on a curved surface, even if the tool reaches the boundary point of the region, and to prevent cutting. To provide a tool path control method that can prevent burns and prevent burns even on workpieces or woodworking.

Another object of the invention is that when the first boundary point of the region is reached,
The first boundary point is calculated until the second boundary point that leaves the area is calculated.
The tool escapes to an escape point near the boundary point, and the tool is rotated and stopped at the escape point. This prevents the tool from coming into contact with the workpiece when stopped, preventing cutter marks from being made on the workpiece, and also prevents cutting. It is an object of the present invention to provide a tool path control method that can prevent dirt from forming and also prevent a workpiece from being scorched.

Still another object of the present invention is to specify in advance the moving speed at which the tool is moved from the first boundary point to the second boundary point, and to determine whether the moving speed is rapid traverse or cutting feed. It is an object of the present invention to provide a tool path control method for determining a path through a region.

Another object of the present invention is to provide a tool path control method that enables groove machining when passing through an area by previously setting the position of the area passing path below the position of the first boundary point.

Still another object of the present invention is a tool path control method in which a convex portion can be machined when passing through an area by setting the area passing movement speed as the cutting feed in advance and setting the area passing path above the first boundary point. and Party B who provides the.

<Summary of the Invention> The present invention is a tool path control method in a numerical control device that calculates a tool path using data specifying a curved surface and moves the tool along the tool path. , FIL 1 i'? inputting data including at least data specifying a region on the curved surface. -y+
-f -i+,'llll+1rii lp th%:
-d-7s Te'7 GI ITI 01 Second step of calculating the tool path for moving the tool along the curved surface; Third step for moving the tool along the tool path; A fourth step is to determine whether the boundary point has been reached. When the tool reaches the first boundary point of the area, the tool is moved away from the boundary point toward the outside of the area and stopped. A fifth step is to identify the curved surface. A sixth step is to calculate a second boundary point where the calculated tool path exits the area using the data, a seventh step is to move the tool to the second boundary point, and the tool is then moved along the calculated tool path. It has an eighth step of moving the .

<Example> FIG. 4 is a schematic explanatory diagram of the present invention, and FIG. 4 (A) shows an example in which the area passing speed is set to fast forward in advance, and the area passing path APP is set above the first boundary point B1. Then, after the tool TL reaches the first boundary point B1, the tool is released to the escape point 1-EP near the first boundary point, and after the second boundary point B2 is calculated, the tool is moved rapidly in front of the area passing path APPPPP. This is a case in which the tool is moved upward and forward on the area passing path to the second boundary point B2 by simultaneous two-axis control of X and Y, and then the tool is positioned at the second boundary point B2 by rapid traverse.

In the same figure (B), the area passing speed is set to cutting feed in advance, and the area passing path APP is set above the first boundary point BJ, and after the tool T L reaches the first boundary point B1, the tool After the second boundary point B2 is calculated, the tool is positioned to the first boundary point B1, and then the tool is moved to the area passing path by cutting feed. Move it along the convex part PR until it reaches X, Y.
The tool is moved above the second boundary point B2 by cutting feed on the path passing through the area by simultaneous two-axis control, and finally the tool is moved to the second boundary point B2.
This is a case where the cutting feed is carried out until it reaches the point where it is moved along the convex portion PR.

In the same figure (C), the area passing path is set to the cutting feed in advance, and the area passing path APP is set below the first boundary point B1, and after the tool T L reaches the first boundary point B1, the area passing path APP is set below the first boundary point B1. Move the tool to the escape point I-E near the first boundary point B1.
After the second boundary point B2 is calculated, the tool is moved to the first boundary point B1, and then the tool is lowered by cutting feed to the area passing path APP, and then X, Y
At the same time, with two-axis control, the second boundary point B2 is moved downward and forward while cutting and feeding on the passage passing through the area and machining the groove, and finally, the second boundary point B2 is
This is a case where the tool is moved by cutting feed to the boundary point B2.

Fig. 5 is a block diagram of a numerical system 'jflll device that implements the present invention, Fig. 6 is a flowchart of the processing of the present invention, and Fig. 7 is an explanatory diagram of data specifying a curved surface and data specifying an area. be.

In FIG. 5, 101 is a keyboard having keys for inputting various data; 102 is a processor; 103 is a ROM for storing control programs; 104t; J-RAM;
05 is working memo IJ, 106 is pulse distributor, 1
07 is a servo circuit, 108 is a motor for each axis, 109 is a display device, and 110 is an operation panel.

The passage control process of the present invention will be explained below.

(,) First, from the keyboard 101 (a) Three-dimensional curved surface 1
0 (see Figure 7), cross-sectional curve information of the curved surface cut by the cross-section, and other necessary information, (b)
A projection curve 31 a obtained by projecting the external curve 31 of the region 30 on the three-dimensional curved surface onto the x-y plane is specified as deviation data, (c)
Data specifying the escape point EP (see Figure 4), (
d) Input the Z-direction position (height) Zp of the area passing passage and (e) the area passing speed Fp, respectively. These input data are stored in the AM 104. Note that the three-dimensional curved surface 10 has, for example, cross sections 11, 12, 21, 22 and 1
Cross-sectional curve 11a, 1 of 72 curved surface cut by 1.12
2a and the cross-sectional curves 21a and 22a of the curved surface cut by the cross section 21.22.

(b) After the above various data have been input, if you press the start button (not shown) on the operation panel 1]0, the processor 102
calculates the tool path on the curved surface according to the control program stored in
i+1mu-1fe;-J-Xm+Ib'iG;I-M
JP/.

Please refer to the specification of Patent Publication No. 5109 of 1981 for the method of calculating position data.

(e) Once the point position on the first curved surface has been calculated, the processor 102 determines the contents of the built-in flag I/register 102a. When the flag is 1, it is assumed that the tool has reached the first boundary point B1, and when the flag is 0, the tool has not reached the first boundary point B1 or has already passed the first boundary point. It is assumed that The initial value of the flag is set to O.

(d) If the flag is 0 as a result of the determination process in step (c), the processor 102 calculates an incremental value for each axis using the point data and the current position data stored in the working memory 105. Each axis shift fil+tiL for ΔT seconds is calculated and input to the pulse distributor 106. The pulse distributor executes a pulse distribution calculation based on the input movement amount of each axis to generate a distribution pulse, and inputs the distribution pulse to the servo circuit 107. As a result, the tool moves on the curved surface from the current position toward the points calculated in step (b).

Note that the processor 102 calculates the current positions Xa and Ya in each axis direction.
, Za/e are updated using a well-known method. That is, the processor 102 moves each axis in T seconds to a predetermined time based on the calculated incremental value of each axis and the cutting speed for cutting the curved surface! l1II view Δx1ΔY,
ΔZ is calculated and the movement amount of each axis is outputted to the pulse distributor 106 every 61 seconds, and the following formula % () () () is calculated to calculate the current position of each axis Xa, Ya, Za is updated (sign depends on direction of movement).

In addition, the processor 102 calculates the remaining movement JtLXr, Yr, Zr (the initial values of Xr, Yr, and Zr are the calculated incremental values) every Δ'F seconds using the following formula % Formula % (2) (2) Updated.

(e) Then, the processor 102 determines the current position '(la
) ~ (1c) Each time the formula is updated, check whether the projection point of the current tool position on the X-Y plane (its coordinate values are Xa, Ya) has already reached the area specified in step (1). Determine.

(f) If X r = Y r = Z r = 0 without the tool reaching the area, that is, if the tool reaches the point calculated in step (b) without reaching the area, step ( Returning to step (b), calculate the point on the next curved surface using the prosensor and repeat the process from step (c) onward.

(g) On the other hand, if the tool reaches the area 30 while moving in step (e) (the reached point is referred to as the first boundary point), the processor 102 will continue to move each axis by the amount Δx even if T seconds have elapsed.
The tool is stopped at the first boundary point B1 without outputting 1ΔY and ΔZ to the pulse distributor 106. Also, if Processera→J, the current position i7/Xn, Yn, Zn of each axis of the first boundary point is stored in the working memory as the coordinate values Bx, By, Bz of the first boundary point B1; Q.

(h) Next, the processor 102 uses the flag register 10
Set flag 2a to 1.

(i) After reading L, the processor executes the escape point 1.L stored in RAM 104. The data regarding E P is used to escape the tool to the escape point l-E P. Note that the data regarding the escape point is, for example, x, y,
The predetermined escape movement amounts in the z-axis direction are ΔX1Δy and ΔZ.

Therefore, the processor uses the escape movement amount to perform the same process as the passage control, and moves the tool to the escape point 1-EP. Note that only ΔZ may be given by assuming that the escape point EP is a point that is a predetermined amount ΔZ from the point on the curved surface one position before. If the tool moves to the escape point E I' through the above processing, step (b)
Returning to step N, the processor calculates the position of the point within region 30 (white circle in FIG. 1), and then steps N) Now, since the flag is set to 1 after the tool reaches the second boundary point 131, By determining step (r, ], step (d
The process does not proceed to path control of path 1, but the following processing is performed.

(k) That is, the processor 102 determines whether the point calculated in step (b) is located outside the area.

(m) If the point exists inside the area 30,
Returning to step (b), step 102 executes the calculation for the next point, and step (k
) is repeated. Thereafter, the point calculation process and the process of determining whether the point is out of the area 30 are repeated until the point is out of the area.

(n) When the point leaves the area 30, the position data Bx', By', Bz' of the point is stored in the working 105 as the position of the second boundary point B2.

(0) After that, Procera → J102 stores in RAM10 whether the speed of passing through the area is rapid feed or cutting feed.
4 to 5 From the Senkoho that I remember, size 51f1 - (p)
In the case of fast forwarding, the processor 102 performs passage control processing using the height direction position (Z-axis direction position) Zp of the area passage passage APP stored in rt8 and the Z-axis coordinate value of the escape point. , move the tool in rapid traverse to the area passing path APP.

After (q)L, the processor positions the tool on the second boundary point B2 in rapid traverse by simultaneous two-axis control, and finally positions the tool on the second boundary point B2 in rapid traverse.

(1) When the tool reaches the second boundary point B2, the process →
Step 102 sets the flag to 0, jumps to step (b), calculates points on the curved surface again, moves the tool on the curved surface based on the point data, and continues curved surface machining.

(S) On the other hand, as determined in step (0), if the cutting feed is set as the speed to pass through the area, the
1) 102 performs the path control processing using the coordinate values of the first boundary point B1 and the coordinate values of the escape point L-EP stored in the working memory 105 to move the tool to the first boundary point. .

(t) After that, the processor uses the position Zp of the area passing path A P I) stored in the RAM 104 and the Z direction position of the first boundary point B1 to move the tool by cutting feed to the area passing path APP. let After reaching the area passing path, simultaneous two-axis control is performed using the X and Y coordinate values of the second boundary point, and the tool is moved upward or downward by cutting feed. If the position Zp of the area passing passage is set above the first boundary point, the tool will move along the convex portion PR (see Fig. 4) by cutting feed, and the position Zp of the area passing passage will be set above the first boundary point. If it is set below the first boundary point, the tool moves along the area passing path while cutting grooves.

(u) After the tool reaches above or below the second boundary point B2, move the tool to the first boundary point B2.

Then, when the tool reaches the second boundary point B2, step (
Jump to step (b), set the flag to 0, and return to step (b).

Thereafter, points on the curved surface are sequentially determined, and the points are used to move the tool along the curved surface to process the curved surface.

<Effects of the Invention> As explained above, according to the present invention, when a tool reaches an area set on a curved surface, the tool is temporarily released to an escape point near the area, and the tool is rotated using the escape point. Because it was configured to stop the movement while moving,
The tool does not come into contact with the workpiece when stopped, so no cutter marks are left on the workpiece, and no overcutting occurs. In addition, since the tool does not come into contact with the workpiece when stopped, the workpiece will not be scorched or burned even if the workpiece is made of a combustible material such as wood. Furthermore, in the present invention, the speed of passing through the area is rapid traverse or cutting feed, and depending on whether the area passing path exists above or below the first boundary point. Since the tool path that passes through the area is controlled, if you want to groove an area, just set the cutting feed and set the position of the area passage path below the first boundary point, and the groove will be automatically machined. If you want to move the tool while machining a convex part on the area, set the cutting feed and set the area passage path above the first boundary point to automatically move the convex part. The shaped part is processed.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of the curved surface machining method using the offline method, and Figures 2 and 3 show problems with the online method, which calculates the path using a take that specifies the curved surface, and immediately moves the tool using the path data. 4 is a schematic explanatory diagram of the present invention, FIG. 5 is a block diagram of a numerical control device that implements the method of the present invention, FIG. 6 is a flowchart of the process of the present invention, and FIG.
The figure is an explanatory diagram of data for specifying a curved surface and a boundary on the curved surface. B1...first boundary point, B2...second boundary point, EP・
・Escape point, APP...area passing passage, TL・
... Tool, 10... Three-dimensional curved surface, 30... Area patent applicant Fanuc Co., Ltd. agent Patent attorney Chiki Saito Figure 1 Figure 2 Figure 4 (A) (C) 6I) 1 ( AJ Figure 6 (BJ Figure 7 10

Claims (6)

[Claims] (1) In a tool path control method in a numerical control device in which a tool path is calculated using data specifying a curved surface and the tool is moved along the tool path, the data specifying the curved surface and the area on the curved surface are calculated. A first step of inputting data including at least identifying data, a second step of calculating a tool path for moving the tool along the curved surface using the data identifying the curved surface, and moving the tool along the tool path. a third step, determining whether the tool has reached the first boundary point of the region; a fourth step, when the tool has reached the first boundary point of the region, moving the tool away from the boundary point toward the outside of the region; A fifth step is to calculate a second boundary point where the calculated tool path leaves the area using the data specifying the turn, and a sixth step is to move the tool to the second boundary point from R+ to 4+1. A tool path control method in a numerical control device having an eighth step. (2) The data of the first step includes the amount of movement of each axis to release the tool from the first boundary point, and in the fifth step, the amount of movement of each axis is calculated! l1lJ'3. T! A tool path control method according to claim 1, characterized in that the tool is caused to escape to an escape point that is distant from the first boundary point. (3) The second step sequentially calculates a sequence of points on the curved surface,
A straight line connecting the point sequence is output as a tool path (7. In the third step, the straight line connecting the point sequence calculated in the second step and the current position is set as the tool path, and the tool is moved along the tool path. and the fifth step is characterized in that when the tool reaches the first boundary point, the tool escapes to an escape point that is a predetermined amount above the point specifying the previous tool path. ) The tool path control method described in section 2. (4) The first step data includes data specifying whether to move the tool to the second boundary point by rapid traverse or by cutting feed, and the area passing when passing through the area. In the seventh step, when rapid traverse is specified, the tool is raised from the stopping point on the area passing path by rapid traverse, and then moved along the area passing path by rapid traverse. 2. The tool path control method according to claim 1, wherein the tool is moved to the second boundary point, and then the tool is rapidly lowered to the second boundary point. (5) The seventh step is to move the tool from the stopping point to the first boundary point when cutting feed is commanded;
Then, if the area passing path exists above the first boundary point, the tool is raised from the first boundary point on the area passing path with a cutting feed, and then the tool is raised along the area passing path with a cutting feed. The tool path control method according to claim 4, characterized in that the tool is moved above the boundary point, and then the tool is moved by cutting feed to the second boundary point. (6) The seventh step moves the tool from the stopping point to the first boundary point when cutting feed is commanded;
Then, if the area passing path exists below the first boundary point, the tool on the area passing path is lowered from the first boundary point with a cutting feed, and then the tool is processed along the area passing path with a cutting feed. The tool path control method according to claim 4, characterized in that the tool is moved to below the second boundary point while performing line C), and then the tool is moved to the second boundary point by cutting feed.