JPS60232826A - Taper machining in wire electric discharging machine - Google Patents

Abstract

PURPOSE:To effectively machine a taper angle which is partly continuous and in other parts constant by entering in mixture command data for executing taper machining at a specified taper angle and command data for executing taper machining in a specified wire electrode passage on the upper and lower surfaces of a work. CONSTITUTION:When taper machining is performed in a wire discharging machine, command passages of the current block bi and next block bi+1, taper angles alphai, alphai+1 and thickness I of a work are used to obtain the wire electrode location on the lower surface of the work at the end of each block. Therefore, when alphabets U, V are not included in the passage data, NC data of the current block and the next block are used to execute the processing so as to obtain the location (X1, Y1) of the block end on the lower surface of the work, and then location deviation vector u, v at the block and is calculated. Thus, taper machining can be performed easily with high precision.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a taper machining method in a wire electric discharge machine, and in particular, first command data for specifying a taper angle and performing taper machining, and two planes. The present invention relates to a taper machining method in which taper machining is performed by inputting a mixture of path data specifying path data (for example, on the upper and lower surfaces of a workpiece) and second command data for executing taper machining.

<Prior art> As is well known, a wire electrical discharge machine is a machine in which a wire electrode is stretched between an upper guide and a lower guide, and an electrical discharge is generated between the wire electrode and the workpiece to machine the workpiece. The workpiece is fixed on a table and moved in the X and Y directions along the machining shape according to commands from a numerical control device. In this case, if the wire electrode is stretched perpendicularly to the table 1 workpiece), the machining shape of the upper and lower surfaces of the workpiece will be the same, and the upper guide will be moved in the x, y direction (U
For example, if the upper guide is moved in a direction perpendicular to the direction of movement of the workpiece and the wire electrode is tilted relative to the workpiece, the machining shape of the upper and lower surfaces of the workpiece will be the same. Instead, so-called taper processing is performed, in which the machined surface is inclined.

FIG. 2 is a schematic explanatory diagram of such taper processing, and a wire electrode WR is stretched between an upper guide UG and a lower guide DG so as to be inclined at a predetermined angle with respect to the workpiece WK. Now, let the lower surface PL of the workpiece WK be a program shape (the upper surface QU of the workpiece WK may be a program shape), the Taber angle is α, and the distance from the lower guide DC to the lower surface of the workpiece is h1 from the lower guide DG to the upper guide UG. If the distance is H, then the offset amount d1 of the lower guide DG with respect to the lower surface PL of the workpiece is
The offset amount d2 of the upper guide UG is as follows: d1='h-tanα+ (d/2) d=H-tana-h-tana-(d/2)
It can be expressed as =H-tanα-d. Note that d is the processing width. Therefore, for example, if the movement of the upper guide UG on which the wire electrode WR is stretched is controlled so that the offset amounts d1, d become constant as the workpiece moves, wire electrical discharge machining with a constant taper angle can be performed as shown in FIG. I can do it. In addition, in FIG. 3, the dotted line and the one-dot chain line are the passages of the upper guide UG and the lower guide DG, respectively.

Now, when performing taper machining in such a wire electric discharge machine, generally speaking, (a) a programmed path on the lower surface of the workpiece or the upper surface of the workpiece, the workpiece thickness I, the Taper angle α in each block, and the distance H are commanded. or (b) the program path on the lower surface of the workpiece or the upper surface of the workpiece, the positional deviation vector (u, , v,) on the upper surface and lower surface of the workpiece at each block end, and the distance gi
h and H are commanded, and processing as commanded is performed based on these data.

<Disadvantages of the prior art> Now, according to the method of performing taper machining by commanding the Taber angle as described in (,) above, when the Taber angle is constant in all blocks or when the Taber angle in each block is constant, If the command data can be easily created, or if the taper angle in a certain block changes continuously, the post-processing of taper machining becomes complicated, and there is a drawback that high-precision taper machining cannot be performed.

On the other hand, in the method (b) of performing taper machining by commanding the positional deviation vector, even if the taper angle in a certain block changes continuously, the taper machining path can be easily identified, and the post-processing However, when the taper angle is constant in all blocks, the command method (a) has the disadvantage that the creation of path data is more complicated than the command method (a).

By the way, as mentioned above, the conventional taper machining command method (
Either one of methods a) and (b) was used. Therefore, if almost all the blocks have a constant Taber angle and the Taber angle changes continuously in only one part (method al. The machining process becomes complicated, highly accurate taper machining cannot be performed, and the method (b) has the disadvantage that it takes time to create command data.In other words,
With conventional command methods, command data can be easily created, post-processing is simple, and taper processing with high precision cannot be performed.

<Object of the Invention> The object of the present invention is to perform taper processing by specifying first command data for performing taper processing by specifying a taper angle, and path data on two planes (for example, the upper and lower surfaces of the workpiece). It is an object of the present invention to provide a taper machining method in a wire electric discharge machine that performs taper machining by commanding a combination of command data and second command data for executing.

Another object of the present invention is to provide a taper processing method suitable for application to taper processing in which the Taper angle changes continuously in one part and is constant in other parts.

<Summary of the Invention> The taper machining method in a wire electrical discharge machine of the present invention includes:
A mixture of first command data that specifies the taper angle and performs taper machining, and second command data that specifies path data on two planes (top and bottom surfaces of the workpiece) and performs taper machining. command, determines whether it is the first command data or the second command data, and if it is the first command data, calculate the guide movement data using the taper angle, and if it is the second command data, determine the guide movement data. The guide movement data is obtained from the path data obtained, and the taber processing is executed based on the movement data. According to this invention, since two types of command data can be mixed, it is easy to create command data even when the taper angle changes continuously in one part, and moreover, it is possible to easily create the command data. Be able to perform easy and highly accurate taber machining.

<Example> FIG. 1 is a plan view of a processed shape for explaining the present invention in detail, and the workpiece top surface shape UF is a square with sides of 20 mm. Furthermore, among the tapered surfaces TPi (i=1.2.3.4), the Taper angle is constant (2°) from TPI to TP3, and the Taper angle changes continuously on the tapered surface TP4. .

Now, as shown in Figure 1, the center of the square is the origin (0,0)
, HL is the machining start hole (its coordinate value is (-5°0)), the workpiece thickness is 25, and the wire electrode is moved relative to the workpiece in the direction of the arrow from the machining start hole HL. If so, the numerical control data is as follows: G92X-5,0Y0.01-25. o;G42G5
2X-5, OT2. o; YIo, 0°X20,0°Y-20,0UuVv; X-20,0°Ylo, 0°G40G50X5. o; X02; Commanded. However, G92 is the G function command for setting the coordinate system, G42 is the G function command indicating the wire diameter offset direction,
G52 is the G function command that indicates the wire inclination direction, G40 is the G function command to cancel the wire diameter offset, G50 is the G function command to cancel the inclination direction, and the alphabet I is the word address word that commands the workpiece thickness (the code is from the program side). ), Alphabella I
-T is a word address word that commands the Taber angle, alphabets X and Y are word address words that indicate that the numerical values are incremental values in the X and Y axis directions on the program surface, and alphabets U and V are hereafter used. The following numerical values (u, v) are word address words indicating the positional deviation vector between the wire paths at the end of the block on the workpiece and the bottom surface, and X02 is the M function command indicating the end of the program.

In the present invention, the position deviation vector (u, v)
In blocks other than the blocks for which is commanded, taper machining control is performed based on the most recently commanded taper angle, while for blocks for which position deviation vector is commanded, the fitting deviation vector is used. Taper machining control is performed.

Fig. 4 is a block diagram of an apparatus for implementing the Taber processing method according to the present invention, Fig. 5 is a flowchart of the process of the Taber processing method of the present invention, and Figs. 6 and 7 are movement data of the upper guide and lower guide. It is an explanatory diagram of a generation method.

In FIG. 4, 11 is a processor, 12 is a ROM 113 that stores a control program, and numerical control data (NC
RAM 114 that stores C deck and other data is NC
An NC data reader that reads NG data from the tape 15, 16 an operation panel, 17 a pulse distributor, 18X,
18Y, 1.8U.

18VLt each axis saho circuit, 19X, 19Y, 19U,
19Vi is a motor for each axis, 20 is a wire electric discharge machine, 21
is an interface for exchanging data between the processor 11 and the wire electric discharge machine.

In advance, from the operation panel 16, the distance H between the lower guide DG and the upper guide UG and the lower guide D shown in FIG. 2 or FIG.
Set and input the distance between G and the lower surface of the workpiece and store it in the RAM 13. Also, use the NC data reading device 14 to
After reading the NC data from the C tape 15 and storing it in the RAM 13, if you press the start button on the operation panel, the processor 11 will take two blocks of NC data from the RAM 13 under the control of the control program. read.

(b) The processor determines whether the NC take of the current block among the read NC takes is MO2. MO2
If so, the process ends, and if it is not MO2, it is determined whether the NC data is a path take.

(c) If the NC take is not path data, for example, if it is coordinate system setting data that includes the workpiece thickness ■ described above, the coordinate system setting process and the storage process of the workpiece thickness I in the RAM 13 are performed, and the next The NC data of the block is read from the RAM 13, and the processing from step (b) onwards is repeated.

(d) On the other hand, if it is passage data, the alphabet U1 commands the position deviation vector (u, v) to the passage data.
■Determine whether or not it is included.

(e) If the alphabets U and ■ are included, the movement vector of the upper guide and lower guide (x, y
, ), (x,,y-).

X = X - (H-h-1) ・u/I, (1)
Y = Y −(H−h−1) −v/ I (2)X
=X + (I+h) ・u/I (3)Y =Y
+ (I+h) ・v/ I (4) However, as shown in Fig. 6, the incremental values x1 and ¥1 in the X and Y axis directions on the top surface of the workpiece and the workpiece viewed from the command position QU on the top surface of the workpiece at the block end. It is assumed that the positional deviation vectors u and v up to the wire electrode position PL on the lower surface are commanded, respectively, and that the workpiece thickness is .

Incidentally, if the incremental values x2, Y2 in the XXY-axis directions on the lower surface of the workpiece and the position deviation vectors u, v from the commanded position on the lower surface of the workpiece at the block end to the wire electrode position on the upper surface of the workpiece are commanded, the upper , the movement vector of the lower guide (Xu.

Y), (x, y) are the following formulas % formula % (5) (6) (7) (8) It's hard to believe.

(f) Then, the processor 11 has a predetermined 6
The amount of movement ΔX of the upper guide and lower guide that moves per second,
Δy, Δu1ΔV are the command speeds, and the above Xu, Yu,
Measure using Xd, Y, etc.

(g) After that, the processor 11ζ
Δu1ΔV is input to the pulse distributor 17 every 61 seconds.

As a result, the pulse distributor 17 executes a pulse distribution calculation, causes each axis servo circuit 18X to 18■ to perform each axis morph 19.
Rotate X to 19V to move the wire electrode relative to the workpiece to execute Taber machining as instructed. Note that the processor 11 calculates Δx1Δy1 for each axis every 61 seconds.
The current position and the remaining amount of movement in the current block are updated in accordance with the movement direction by Δu1ΔV.

(h) The above path control process is performed until the wire electrode reaches the end point in the IJt&,i block, and when the wire electrode reaches the end point of the current block, the next NC take is read and the same process as described above is repeated.

(i) As a result of the determination in step (d), if the NC data does not include the alphabets U, . Find the position deviation vector (u, V) from the command position at the end to the wire electrode position on the bottom surface of the workpiece.

Now, as shown in Fig. 7, points A, B, and C at each block end on the upper surface of the workpiece.

D..., the distinction between straight line and circular arc in each block, and the Taber angle α (1-1, 2, 3...) in each block b, (i=1.2.3...) are commanded. Assuming that, the wire electrode positions A', B', C', . . . of each block on the lower surface of the workpiece are determined as follows.

That is, the coordinate values of point B' on the lower surface of the workpiece of the wire electrode at the end of the first block b are as follows:
Command line AB to I on the top surface of the workpiece of block b1
-tan α From the straight line L1 offset by 1 and the command straight line BC on the upper surface of the workpiece of the second block b2
It is set as the intersection with the straight line L2 offset by α2. or,
The coordinate value of point C' on the lower surface of the workpiece of the wire electrode is at the end of the second block b.
The line L is offset by I-tanα from the command straight line BC on the upper surface of the workpiece of the third block b, and the circular arc ARC is offset by I-tanα from the commanded arc CD on the upper surface of the workpiece of the third block b.

Then, similarly, the current block b1 and the next block b1
+1 command path and Taber angle. 1, α, +1, and the thickness of the workpiece ■, the wire electrode position on the lower surface of the workpiece at the end of each block is determined. Therefore, if the path data does not include the alphabet U1v, the above process is performed using the NC data of the current block and the next block, and the block end position (xl
, Yl), and then, using these position coordinate values at the block ends on the upper and lower surfaces of the workpiece, positional deviation vectors u and v at the block ends on the dark upper and lower surfaces are calculated using the following formula.

(i) If the positional deviation vectors u and v are equal, step (
e) Execute the Jff drop process.

<Effects of the Invention> As explained above, according to the present invention, the first command data specifies the taper angle to perform taper processing, and the wire electrode path on the upper and lower surfaces of the workpiece is specified to perform taper processing. Since the configuration is configured so that commands are issued in combination with the second command data, even if the taper angle changes continuously in one part and the taper angle remains constant in the remaining part, it can be easily processed. In addition to creating numerical control data, it is possible to easily perform taper processing and to perform highly accurate taper processing.

[Brief explanation of drawings]

Fig. 1 is a schematic explanatory diagram of the present invention, Figs. 2 and 3 are explanatory diagrams of conventional taper machining, Fig. 4 is a block diagram of an apparatus for realizing taper machining according to the present invention, and Fig. 5 is a diagram of the present invention. The processing flowchart of the tapering method, and FIGS. 6 and 7 are explanatory diagrams of guide moving scene data calculation according to the present invention. UG... Upper guide, DG... Lower guide, W
R...Wire electrode, WK--Work, 11...Processor, 17...Pulse distributor Patent applicant Fanuc Corporation representative Patent attorney Chiki Saito Figure 1 Figure 4 Figure 5

Claims (2)

[Claims] (1) In the taper machining method for a wire electrical discharge machine, in which the workpiece is moved relative to the wire electrode and the guide on which the wire electrode is stretched is moved horizontally to perform taper machining on the workpiece, the taper angle is specified. First command data for performing taper machining and second command data for specifying path data on two planes and performing taper machining are mixed and commanded, and the first command data is used as the second command data.
If it is the first command data, the guide movement data is determined using the taper angle, and the second command data is determined.
A method for taper machining in a wire electrical discharge machine, characterized in that if the command data is, guide movement data is determined from given path data, and taper machining is executed based on the movement data. (2) The taper machining method in a wire electric discharge machine according to claim (1), wherein the two planes are an upper surface and a lower surface of the workpiece.