JPH072289B2 - Wire electric discharge machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a wire electric discharge machining apparatus that graphically displays a machining locus of a workpiece on a display device.

[Conventional technology]

FIG. 4 is a schematic configuration diagram showing a conventional wire electric discharge machine. In the figure, 12 is a workpiece, 10 is a movable table for mounting and fixing the workpiece 12, 16 and 20 are sliding parts, and 14 and 18 are drive motors for moving the sliding parts 16 and 20, 22 is a numerical control device that gives signals to the drive motors 14 and 18, 24 is a wire forming an electrode for processing the workpiece 12, 30 and 32 are wire guides for supporting the wire 24, and 26 is a wire 24. A wire bobbin around which a wire is wound, 36 is a tension roller for winding the wire 24, 38 is a wire winding roller for collecting the used wire 24, and 28 and 34 are the wire 24 and the workpiece 1
2 is a power supply unit for applying a voltage, 40 is a power supply device, 42 is a DC power supply in the power supply device 40, 44 is a DC power supply 42 ON-OF
F is a switching transistor for forming a pulse waveform, 50 is a control unit for controlling the switching transistor 44, 48 is a limiting resistor, 46 is a charging capacitor, 52 is a machining fluid device, and 54 is a discharge medium. Machining fluid, 56 is a machining tank that accumulates machining fluid 54, and 58 is machining fluid
A filter for filtering 54, a pump 60 for pumping the machining liquid 54, and a nozzle 62 for supplying the machining liquid 54 to the workpiece 12.

Next, the operation of the conventional wire electric discharge machine shown in FIG. 4 will be described. The work piece 12 is placed and fixed on the movable table 10, and the movable table 10 is a drive motor.
The position is controlled by the numerical controller 22 in the X-axis direction by 14 and in the Y-axis direction by the drive motor 18. The power supply device 40 is connected to the wire 24 via the power supply units 28 and 34.
The voltage V of the DC power supply 42 is applied through the charging capacitor 46 by the switching transistor 44 and the control unit 50 thereof. On the other hand, the machining fluid 54 filtered by the filter 58 in the machining fluid device 52 is pumped out by the pump 60 and supplied as a discharge medium between the workpiece 12 and the wire 24. Therefore, electric discharge is generated between the wire 24 and the workpiece 12, and the machining can be performed according to the instruction of the numerical control device 22. The numerical control device 22 outputs a position control signal according to an NC (numerical control) program, and at the same time, displays a CRT (cathode ray tube) display device and the like such as NC coordinates and machining conditions.

[Problems to be solved by the invention]

In the conventional wire electric discharge machine as described above, the workpiece
It often happens that 12 is short-circuited with the wire 24 forming the electrode. Due to this short circuit phenomenon, the wire 24 and the work piece 12
There is a possibility that troubles such as a change in the working gap and streaks may occur because the electric discharge is stopped or the electric energy of the discharge is changed due to the continuity between the gaps. When such a short circuit situation occurs, when performing inspection and rework after finishing the machining,
Since the location of the short circuit is unknown, there is a problem that the work efficiency is significantly reduced.

The present invention has been made to solve such a problem, and an operator can easily find a short circuit portion between a wire forming an electrode and a workpiece on a pattern of a machining trajectory of the workpiece currently being machined. The purpose is to obtain a wire electric discharge machine that can be understood and confirmed.

[Means for solving problems]

The wire electric discharge machining apparatus according to the present invention graphically displays the machining locus of the workpiece currently being machined on the display device, and also displays the short-circuited portion between the wire forming the electrode and the workpiece on the display device. It is designed to be displayed in.

[Action]

In the wire electric discharge machining apparatus of the present invention, when the machining locus of the workpiece currently being machined is graphically displayed on the display device by the drawing means, and when the wire forming the electrode and the workpiece are short-circuited Then, the short-circuited portion is displayed on the machining trajectory graphic so that the operator can easily understand and confirm the short-circuited portion after the processing is completed.

〔Example〕

FIG. 1 is a diagram showing a CRT screen of a CRT display device displayed by a wire electric discharge machine which is an embodiment of the present invention, and FIG. 2 is a process in the wire electric discharge machine which is an embodiment of the present invention. FIG. 3 is a block diagram showing a control program in the wire electric discharge machine which is one embodiment of the present invention. In FIG. 3, the PREPRO program decodes the NC data from the paper tape and passes the data necessary for moving the table to the MOTION program. MOTION
The program outputs a signal to the drive motor that moves the table based on the passed data. Also, the DISPLAY program displays each coordinate value and the like on the CRT screen of the CRT display based on the above data, and at the same time draws a graphic on the CRT screen. Further, the short-circuit detecting device detects a short circuit between the wire forming the electrode and the workpiece, and gives a signal to the MOTION program.

Next, the operation of the wire electric discharge machine according to the embodiment of the present invention will be described with reference to FIGS.
First, the contents of the NC program are deciphered by the PREPRO program, and the data required for table movement etc. is passed to the MOTION program. Next, the MOTION program calculates specific coordinate values, gives a signal to the drive motor, and at the same time passes the coordinate values to the DISPLAY program. Based on these data, the DISPLAY program draws a machining trajectory corresponding to the shape of the workpiece on the CRT screen as shown in FIG. Next, when the wire that forms the electrode and the work piece are short-circuited during processing, the short-circuit detection device sends a short-circuit signal.
Given to the program, then the PREPRO program calculates the coordinate values and feeds the data to the DISPLAY program. DIS
The PLAY program displays short-circuited points with triangular marks as shown in FIG. 1 on the figure of the machining locus of the workpiece drawn on the CRT screen. By repeating the above-described operation, the machining locus corresponding to the shape of the workpiece shown in FIG. 1 is drawn on the CRT screen. As shown in Fig. 2, the process flow is as follows: after the NC program is decoded, processing is started, and whether or not there is a short circuit is inspected. Remember, then draw with a triangle on the graphic on the CRT screen. Further, if there is no short circuit, the processing can be continued as it is. At the end of processing, a triangular mark is displayed at the short-circuited portion as shown in FIG. 1, and the fact that a short-circuit (wire breakage) has occurred is clearly drawn.

In addition, in the above-mentioned embodiment, the case where the triangular mark is drawn when the short circuit between the wire forming the electrode and the work piece is described, but in addition to this, the case where the processing condition is changed is displayed. You can

〔The invention's effect〕

As described above, according to the present invention, in the wire electric discharge machining apparatus, the machining locus of the workpiece currently being machined is graphically displayed on the display device, and the short circuit location between the wire forming the electrode and the workpiece is also displayed. Since it is displayed as a graphic on the device, it is possible to directly see on the graphic screen where the short circuit occurred during processing of the work piece, and especially after the end of processing, the inspection of that part is possible. In detail, it has an excellent effect that the inspection of the work piece can be performed very easily and surely.

[Brief description of drawings]

FIG. 1 is a diagram showing a CRT screen of a CRT display device displayed by a wire electric discharge machine which is an embodiment of the present invention, and FIG. 2 is a process in the wire electric discharge machine which is an embodiment of the present invention. FIG. 3 is a block diagram showing a control program in the wire electric discharge machine which is one embodiment of the present invention, and FIG. 4 is a schematic configuration diagram showing a conventional wire electric discharge machine. In the figure, 10 ... Movable table, 12 ... Workpiece, 1
4,18 …… Drive motor, 16,20 …… Sliding part, 22 …… Numerical control device, 24 …… Wire, 26 …… Wire bobbin, 28,34
...... Power supply unit, 30, 32 ...... Wire guide, 36 ...... Tension roller, 38 ...... Wire winding roller, 40 ...... Power supply unit, 42 ...... DC power supply, 44 ...... Switching transistor, 46 ...... Charging capacitor, 48 ... Limiting resistance, 50 ...
Control unit, 52 …… machining fluid device, 54 …… machining fluid, 56 …… machining tank, 58 …… filter, 60 …… pump, 62
...... It is a nozzle.

Claims (1)

[Claims] In a wire electric discharge machine equipped with a display device such as a cathode ray tube display device and a control device such as a numerical control device, a drawing means for drawing a machining locus of a workpiece currently being machined on the display device. And a drawing pattern such as a triangle mark in the drawing of the processing locus of the work drawn on the display device for the position of the short circuit portion between the wire forming the electrode and the work by the drawing means. 1. A wire electric discharge machine comprising a program control means for illustrating in FIG.