JPH05162020A - Wire cut electric discharge machining device - Google Patents

Abstract

PURPOSE:To carry out gap machining at the shortest route without experiencing a broken wire due to strain resulting from a machining shape and a material to be machined in gap electric discharge machining. CONSTITUTION:There are provided a remaining movement amount memory means 32, an inverse route computation means 33, a stopping means 34 and a remaining movement amount return means 35. In the case of machining, the movement data from a machining interruption point to its start position are memorized, and in the case of gap machining with the inverse route of the memorized movement data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to core cutting-off control in a wire-cut electric discharge machine.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram of a conventional wire-cut electric discharge machining apparatus. In FIG. 3, reference numeral 1 is a workpiece, which is placed on an X-axis sliding table 3 and a Y-axis sliding table 4. Fixed. X-axis sliding table 3 and Y-axis sliding table 4
Are driven by an X-axis drive motor 5 and a Y-axis drive motor 6, respectively. Further, 7 and 8 are U-axis drive motors,
It is a V-axis drive motor and drives the upper guide 12. A wire electrode 2 is supplied from the wire bobbin 9, and is collected by the collecting roller 14 through the pulley 10, the power feeding die 11 through the upper guide 12, and the lower guide 13. The lower guide 13 is fixed to the machine, and the movements of the U axis and the V axis move relative to the X axis and the Y axis, respectively. Reference numeral 18 is a power supply device for supplying a voltage to the wire electrode 2. 19 is a DC power supply, 20 is a switching transistor for turning the DC power supply ON and OFF, 2
Reference numeral 1 is a charging capacitor, 22 is a limiting resistor, and 23 is a control unit of a switching transistor. The supply of the voltage from the power supply device 18 to the wire electrode 2 is performed via the power feeding die 11. Further, reference numeral 15 is a machining liquid tank, and the machining liquid 16 is supplied to the discharge surfaces of the workpiece 1 and the wire electrode 2 via the pump P. Reference numeral 17 is a controller for the wire cut electric discharge machine, which controls the X-axis drive motor 5, the Y-axis drive motor 6, the U-axis drive motor 7, the V-axis drive motor 8, the power supply device 18, and the supply of the wire electrode 2. control,
The processing liquid 16 is controlled.

Next, the core cutting-off control operation, particularly in the processing of a large number of pieces, will be described with reference to FIG. Figure 2
(A) is an example of a machining shape, and the wire electrode 2 is machined along a route from the start position A to B, C, D, E, F, B, A. The machining program used at this time is as follows. G92X0Y0; G42G01Y10000; G01X10000; G02X0Y-20000I0J-10000; G01X-20000; G02X0Y20000I0J10000; G01X10000; M01; G40G01Y-10000; Next, an actual processing method will be described. When processing a large number of pieces, the "uncut mode" and "cut-off mode", which are the functions of the control device 17, are normally used. This is not done by cutting the work piece by piece,
By inputting the P distance of G-B in FIG. 2B to the control device as an uncut amount, setting the "uncut mode" and starting machining, the solid line portion in FIG. A,
Machining B, C, D, E, F, G, interrupting machining at point G and returning to start position A. After that, the processing moves to the next processing position, the uncut processing is performed in the same manner, and the uncut processing for the designated number of processing ends. Next, by setting the "cut-off mode" and restarting the machining program from the beginning, as shown in Fig. 2 (c), it runs idle from the start position A to B, C, D, E, F, G. Then, the cut-off process from G to B is performed, and the process is temporarily stopped. Here, the worker removes the core and restarts to return to the point A and move to the next processing position. This operation is repeated for the number of processed pieces. In the wire-cut electric discharge machine, it is necessary for the operator to operate where the core is cut off. The above-mentioned "uncut mode" and "cut-off mode"
By using, most of the processing is automatically processed, and only the cut-off portion that requires the operator's operation can be collectively processed in a short time. In order to use the "uncut mode" and "cut-off mode", a specific code designating the cut-off position is input to the machining program, and the M01 code of the program corresponds to this.

[0004]

The "cut-off mode" and "cut-off mode" of the wire-cut electric discharge machine are effective functions for automatic machining as described in the above-mentioned prior art. Depending on the material of the workpiece and the workpiece, distortion occurs in the workpiece at the end of uncut processing, and during cut-off processing, there is a problem that the wire may be disconnected in the middle because it cannot run to the point where uncut To avoid this, it is possible to set a method of advancing to the uncut point while processing even in the idle running part, but since the part that has been processed once is processed again, the processing time is unnecessarily extended and the product processing efficiency is improved. There is a problem that lowers. In addition, when distortion occurs due to the processing shape or the material of the workpiece, when performing uncut processing and cut-off processing,
There is a problem that the uncutting machining program and the cutting-off machining program must be created separately, which complicates the creation of the machining program and takes time. Further, an electric discharge machining apparatus for reversing the program locus is disclosed in, for example, Japanese Patent Laid-Open Nos. 59-30624 and 59-166421. However, these generate a machining program of a reverse locus, but even when the core is cut off, the axial movement does not stop and the lower guide 13 is damaged.

The wire-cut electric discharge machine according to the present invention has been made in order to solve the above problems, and is not affected by the shape of the work or the distortion due to the material of the work piece and can be cut off efficiently in a short time. The object is to obtain a wire-cut electric discharge machine capable of machining.

[0006]

A wire-cut electric discharge machining apparatus according to the present invention comprises a residual movement amount storage means for storing a path from a point where machining is interrupted due to uncut cores to a machining start position, And a reverse path calculating means for calculating a backward movement amount of the remaining movement amount, a stopping means for temporarily stopping at a cut-off completion point, and a remaining movement amount restoring means for restoring the data stored in the remaining movement amount storage means. Is.

[0007]

In the wire-cut electric discharge machining apparatus according to the present invention, the remaining movement amount storage means for storing the route from the point where the machining is interrupted due to the uncut core to the machining start position is used in the uncut mode machining. The relative axis movement remaining data of one block of the machining program being executed when the machining interruption is executed due to the uncut portion and the relative axis movement data of one block for returning to the next start position are stored in the storage means. Further, the reverse path calculating means generates the reverse path axis movement data by reversing the moving direction of the relative axis movement data of each of the stored blocks during the cut-off mode processing, and reverses the order to the execution block. The stop means generates a stop at the time when the reverse path movement for two blocks is completed. The remaining movement amount returning means generates a movement amount to return to the start position after the completion of cutting.

[0008]

EXAMPLES Example 1. An embodiment of the present invention will be described below with reference to the drawings. Figure 1
1 is a functional block configuration diagram of the present invention. In FIG. 1, reference numeral 30 is an axis movement amount calculating means for inputting a machining program 40 to calculate a relative axis movement amount for each block,
The axis movement data 37 in the storage device 36 is output. Reference numeral 31 denotes an axis moving means, which outputs the axis output to the X, Y, U, V axis drive motors 5, 6, 7, 8 based on the axis movement data 37 calculated by the axis movement amount calculating means 30. The axis is moved to advance the machining. While performing this axis movement output, the axis movement means subtracts the axis output amount from the axis movement data 37. First, in the case of the non-cutting mode processing, the processing is advanced by the control method as described above, and the remaining movement amount storage means 32 is activated at the stage when the processing interruption point is reached for the uncutting. The remaining movement amount storage means 32 stores the axis movement data 37, which is the remaining movement amount at the present time, as cut-off source data 38 in the storage device 36. After that, the machining is interrupted, and the remaining movement amount remaining in the axis movement data 37 is output by the axis. After that, the process is executed according to the machining program, but when the axis movement command appears next time, the remaining movement amount storage means 32 is started before the axis movement is started, and the cutoff source data 38 is stored.
The movement data for two blocks is stored for processing the shape. Similarly, at the next processing position, two blocks are similarly cut off and sequentially stored in the original data 38. Next, when the machining is started in the cut-off mode, the axis moving means 31 activates the reverse path calculating means 33. The reverse path calculation means 33 inputs the second block of the cut-off source data 38 first, generates a movement command in which the movement direction is reversed from the remaining movement amount, and creates the axis movement data 37. The axis movement means 31 starts axis movement when the axis movement data 37 is created. When the movement of this block is completed, the axis moving means activates the reverse path calculating means 33 again. When the reverse path computing means 33 is activated for the second time, the first block of the cut-off source data is input and the axis movement data 37 is created. When the axis movement data 37 is created, the axis moving means starts axis movement. 2 above
When cutting off is completed by moving blocks,
The axis moving means stops once by activating the stopping means 34. By this stop, the worker removes the core and restarts. By restarting, the axis moving means 3
1 starts the remaining movement amount returning means 35. Each time the residual movement amount restoring means 35 is activated, it copies from the first block of the cutoff source data 38 to the axis movement data 37 as it is. By activating the remaining movement amount returning means 35 twice, the axis moving means 31 returns to the start position along the same path as the movement of the machining interrupter in the uncut machining.

In the above-described embodiment, since the normal machining program returns to the start position in the block in which the machining interruption due to the uncut portion is executed and the next moving block in most cases, the number of memory blocks is described as two blocks. Two
Of course, even if the number of blocks is exceeded, it is possible to add them using index data.

[0010]

As described above, according to the present invention, since the cutting process is performed in the route opposite to the machining program, the wire may be broken due to the influence of the strain due to the machining shape and the material of the workpiece. Since it can be cut off without using the shortest route, there is an effect that the time required for the operator to cut and operate can be shortened. Of course, it is not necessary to create a machining program for cutting off.

[Brief description of drawings]

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

FIG. 2 is a diagram showing processing contents of uncut and cut-off.

FIG. 3 is a configuration diagram of a wire cut electric discharge machine.

[Explanation of symbols]

 1 Workpiece 2 Wire electrode 30 Axis movement amount calculation means 31 Axis movement means 32 Residual movement amount storage means 33 Reverse path calculation means 34 Stopping means 35 Residual movement amount restoration means

Claims (1)

[Claims] 1. In the processing of a work piece, in a wire cut electric discharge machine having respective cutting modes of uncut core and cut-off, from a point at which machining is interrupted for uncut core, Remaining movement amount storage means for storing the route to the processing start position, reverse route calculation means for calculating the backward movement amount of the remaining movement amount, stopping means and remaining movement amount storage means for temporarily stopping at the cut-off completion point A wire-cut electric discharge machining apparatus having residual movement amount restoring means for restoring the data stored by, and performing cut-off machining in a route opposite to a machining program route.