TWI839195B - Electrical waveform modulation method for wire cutting rough machining - Google Patents

Abstract

A wire cutting rough machining electrical waveform modulation method is applied to a wire cutting discharge machining machine and a machining circuit. The wire cutting discharge machining machine includes a workbench and a cutting copper wire. The machining circuit includes a power source, a first module electrically connected to the power source and the workbench, and a second module electrically connected to the cutting copper wire. The wire cutting rough machining electrical waveform modulation method controls the first module to conduct a first electrode of the power source to the workbench through a control module, and controls the current passing through the workbench to flow to the second electrode through the cutting copper wire after discharge. After a first time, the first electrode of the power source is disconnected from the workbench, and after a second time following the first time, the second electrode of the power source is disconnected from the cutting copper wire to extend the discharge current time.

Description

Electrical waveform modulation method for wire cutting rough machining

The present invention relates to a wire cutting method, in particular to a wire cutting rough machining electrical waveform modulation method.

An existing wire cutting processing method is applied to a processing circuit and a wire cutting discharge processing machine, the wire cutting discharge processing machine includes a workbench and a cutting copper wire, the processing circuit includes a power supply, and a first module and a second module connected in parallel and electrically connected to the power supply, the first module is electrically connected to the workbench, and the second module is electrically connected to the cutting copper wire.

When in use, the current flows from the anode of the power source through the first module, passes through the workbench, and then discharges to the cutting copper wire. After the current passes through the cutting copper wire and the second module, it finally returns to the cathode of the power source. When the workbench is discharged, the high heat generated and the high temperature of the cutting copper wire after power is applied can be used to cut a workpiece to be processed.

Since the discharge current will continue to increase with the power-on time, in order to prevent the cutting copper wire from breaking due to heat accumulation, the power must be supplied intermittently. After the power is supplied for a first predetermined time, the first module and the second module are controlled to be disconnected from the power supply for a second predetermined time at the same time, so that the discharge current can be reduced and the cutting copper wire can be cooled. After that, the power supply and power off process is repeated to complete the wire cutting operation.

However, in order to increase production, the first predetermined time will be increased to obtain more cutting time, but this method is prone to causing the cutting copper wire to break due to heat accumulation, so it is necessary to improve the wire cutting processing method.

Therefore, the purpose of the present invention is to provide a wire cutting rough machining electrical waveform modulation method that overcomes the shortcomings of the prior art.

Therefore, the wire cutting rough machining electric waveform modulation method of the present invention is applied to a wire cutting discharge machining machine and a machining circuit. The wire cutting discharge machining machine includes a workbench for placing a workpiece to be cut and capable of conducting electricity, and a cutting copper wire for cutting the workpiece to be cut after being energized and heated. The machining circuit includes a power source, a first module electrically connected to the power source and the workbench, and a second module connected in parallel with the first module and electrically connected to the cutting copper wire. The wire cutting rough machining electric waveform modulation method controls the first module to conduct a first electrode of the power source to the workbench through a control module, so that the power source A current flows from the first electrode to the workbench, and at the same time controls the second module to conduct the second electrode of the power source opposite to the first electrode to the cutting copper wire, so that the current passing through the workbench is discharged and flows through the cutting copper wire to the second electrode. The control module electrically connects the first module and the second module. After a first time, the control module controls the first module to disconnect the first electrode of the power source from the workbench, and after a second time following the first time, the control module controls the second module to disconnect the second electrode of the power source from the cutting copper wire.

The effect of the present invention is that after the first time, the control module disconnects the first electrode of the power source from the workbench, and after a second time following the first time, the control module disconnects the second electrode of the power source from the cutting copper wire, so that the discharge current can be extended to improve the processing efficiency.

2: Wire cutting EDM machine

21: Parts to be cut

22: Workbench

23: Cutting copper wire

3: Processing circuit

31: Power supply

311: First electrode

312: Second electrode

32: First module

33: Second module

34: Control module

51~53: Steps of the wire cutting rough machining electrical waveform modulation method

D1: First diode

D2: Second diode

D3: The third diode

D4: The fourth second pole

Q1: First field effect transistor

Q2: Second field effect transistor

T1: First time

T2: Second time

Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, wherein: FIG. 1 is a schematic diagram of a wire cutting EDM machine and a processing circuit applied to an embodiment of the wire cutting rough machining electrical waveform modulation method of the present invention; FIG. 2 is a flow chart of the embodiment; FIG. 3 is a waveform diagram of a control module of the embodiment in a first processing mode; FIG. 4 is a waveform diagram of the control module of the embodiment in a second processing mode; and FIG. 5 is a waveform diagram of the control module of the embodiment in a carbon deposition processing mode.

Referring to Figures 1, 2, and 3, an embodiment of the wire cutting rough machining electrical waveform modulation method of the present invention is applied to a wire cutting discharge machining machine 2 and a machining circuit 3.

The wire-cut EDM machine 2 includes a workbench 22 for placing a workpiece 21 to be cut and capable of conducting electricity, and a cutting copper wire 23 for cutting the workpiece 21 to be cut after being energized and heated.

The processing circuit 3 includes a power source 31, a first module 32 electrically connected to the power source 31 and the workbench 22, a second module 33 connected in parallel with the first module 32 and electrically connected to the cut copper wire 23, and a control module 34 electrically connected to the first module 32 and the second module 33.

The power source 31 has a first electrode 311 and a second electrode 312 opposite to the first electrode 311. The first electrode 311 is the anode of the power source 31, and the second electrode 312 is the cathode of the power source 31.

The first module 32 has a first diode D1 connected in series between the second electrode 312 and the workbench 22, and a second diode D2 and a first field effect transistor Q1 connected in parallel and in series between the first electrode 311 and the workbench 22.

The anode of the first diode D1 is electrically connected to the second electrode 312, the cathode of the second diode D2 is electrically connected to the first electrode 311, and the source, drain and gate of the first field effect transistor Q1 are electrically connected to the first electrode 311, the workbench 22 and the control module 34 respectively.

The second module 33 has a third diode D3 connected in series between the first electrode 311 and the cut copper wire 23, and a fourth diode D4 and a second field effect transistor Q2 connected in parallel and in series between the first cut copper wire 23 and the second electrode 312.

The cathode of the third diode D3 is electrically connected to the first electrode 311, the anode of the fourth diode D4 is electrically connected to the second electrode 312, and the source, drain and gate of the second field effect transistor Q2 are electrically connected to the cut copper wire 23, the second electrode 312 and the control module 34 respectively.

The control module 34 can provide control voltages to the first field effect transistor Q1 and the second field effect transistor Q2, respectively, to control the operation modes of the first field effect transistor Q1 and the second field effect transistor Q2, respectively. The first field effect transistor Q1 can be controlled by the control module 34 to make the source and drain of the first field effect transistor Q1 conductive or non-conductive, and the second field effect transistor Q2 can be controlled by the control module 34 to make the source and drain of the second field effect transistor Q2 conductive or non-conductive. In this embodiment, when the control module 34 inputs a high voltage to the gate of the first field effect transistor Q1 and the second field effect transistor Q2, the source and drain of the first field effect transistor Q1 and the second field effect transistor Q2 are turned on. When the control module 34 inputs a low voltage to the gate of the first field effect transistor Q1 and the second field effect transistor Q2, the source and drain of the first field effect transistor Q1 and the second field effect transistor Q2 are turned off.

The wire cutting rough machining electrical waveform modulation method includes the following steps 51~53.

In step 51, the control module 34 controls the source and drain of the first field effect transistor Q1 to be turned on, so that the first module 32 turns the first electrode 311 of the power source 31 on the workbench 22, so that a current of the power source 31 flows from the first electrode 311 to the workbench 22, and at the same time controls the source and drain of the second field effect transistor Q2 to be turned on, so that the second module 33 turns the second electrode 312 on the cut copper wire 23, so that the current passing through the workbench 22 is discharged and flows through the cut copper wire 23 to the second electrode 312.

In the step 52, after a first time T1, the control module 34 controls the source and drain of the first field effect transistor Q1 of the first module 32 to be non-conductive, so as to disconnect the first electrode 311 of the power source 31 from the workbench 22.

In the step 53, after a second time T2 following the first time T1, the control module 34 controls the source and drain of the second field effect transistor Q2 of the second module 33 to be non-conductive, so as to disconnect the second electrode 312 of the power source 31 from the cut copper wire 23.

To further explain, in the step 51, since the current passes through the first field effect transistor Q1 and the workbench 22 in sequence from the first electrode 311 of the power source 31, passes through the cutting copper wire 23 and the second field effect transistor Q2 after discharge, and finally flows back to the second electrode 312 of the power source 31, the high heat generated during discharge will cause the cutting copper wire 23 to generate high heat and can be used to perform wire cutting on the workpiece 21 to be cut. At this time, the discharge current will gradually increase within the first time T1.

In step 52, although the first electrode 311 of the power source 31 is disconnected from the workbench 22, the stored electric energy in the first module 32 is gradually decreasing, so the discharge current continues to act, but the discharge current will gradually decrease within the second time T2. However, the high heat generated during the discharge in this step can still be used to perform wire cutting on the workpiece 21 to be cut.

In step 53, the first electrode 311 of the power source 31 remains disconnected from the workbench 22, and the second electrode 312 of the power source 31 is also disconnected from the cutting copper wire 23. The stored electric energy in the first module 32 and the second module 33 gradually decreases, and the discharge current decreases at a faster rate than at the second time T2 until there is no discharge current at all.

It should be noted that the control module 34 can also switch between a first processing mode, a second processing mode and a carbon deposition processing mode.

When the control module 34 is in the first processing mode, when the first time T1 is between 200ns and 1000ns, the second time T2 is in the range of 1ns~1200ns, and when the first time T1 is not less than 1000ns, the second time T2 is in the range of 1000ns~2000ns. The first processing mode is generally used for rough processing in wire cutting.

Referring to Figures 1, 2, and 4, when the control module 34 is in the second processing mode, when the first time T1 is between 200ns and 600ns, the range of the second time T2 is 1ns~800ns, and when the first time T1 is not less than 600ns, the range of the second time T2 is 800ns~1200ns. The second processing mode is generally used for precision processing after rough processing in wire cutting.

Referring to Figures 1, 2, and 5, when the control module 34 is in the carbon deposition processing mode, when the first time T1 is between 200ns and 600ns, the second time T2 is in the range of 1ns to 600ns, and when the first time T1 is not less than 600ns, the second time T2 is in the range of 600ns to 1200ns. The carbon deposition processing mode is generally used when the cutting copper wire 23 generates carbon deposition.

Since the conduction time of the source and drain of the second field effect transistor Q2 is longer than the conduction time of the source and drain of the first field effect transistor Q1 by the second time T2, the processing time of wire cutting can be extended, thereby increasing the processing speed, and the discharge current will not continue to increase during the second time T2, so that the temperature will not rise, so that there can be a longer processing time. Compared with the existing wire cutting processing method, if the discharge current is to be increased, it may cause the problem of copper wire thermal accumulation and wire breakage. The wire cutting rough processing electrical waveform modulation method can extend the processing time without increasing the temperature, so that the cut copper wire 23 can be prevented from breaking.

In summary, after the first time T1, the control module 34 disconnects the first electrode 311 of the power source 31 from the workbench 22, and after a second time T2 following the first time T1, the control module 34 disconnects the second electrode 312 of the power source 31 from the cutting copper wire 23, so that the discharge current can be extended and the processing efficiency can be improved, so the purpose of the present invention can be achieved.

However, the above is only an example of the implementation of the present invention, and it cannot be used to limit the scope of the implementation of the present invention. All simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the content of the patent specification are still within the scope of the patent of the present invention.

51~53: Steps of the wire cutting rough machining electrical waveform modulation method

Claims (6)

A wire cutting rough machining electrical waveform modulation method is applied to a wire cutting discharge machining machine and a machining circuit. The wire cutting discharge machining machine includes a workbench for placing a workpiece to be cut and capable of conducting electricity, and a cutting copper wire for cutting the workpiece to be cut after being powered on and heated. The machining circuit includes a power source, a first module electrically connected to the power source and the workbench, and a second module connected in parallel with the first module and electrically connected to the cutting copper wire. The wire cutting rough machining electrical waveform modulation method includes the following steps: (A) A control module controls the first module to conduct a first electrode of the power source to the workbench so that a current of the power source flows from the first electrode to the workbench, and simultaneously controls the second module to conduct a second electrode of the power source opposite to the first electrode to the cutting copper wire so that the current passing through the workbench flows to the second electrode through the cutting copper wire after discharge, and the control module electrically connects the first module and the second module; (B) After a first time, the control module controls the first module to disconnect the first electrode of the power source from the workbench; and (C) After a second time following the first time, the control module controls the second module to disconnect the second electrode of the power source from the cutting copper wire. A wire cutting rough machining electrical waveform modulation method as described in claim 1, wherein the control module can switch to a first processing mode. In the first processing mode, when the first time is between 200ns and 1000ns, the second time ranges from 1ns to 1200ns, and when the first time is not less than 1000ns, the second time ranges from 1000ns to 2000ns. A wire cutting rough machining electrical waveform modulation method as described in claim 1, wherein the control module can switch to a second processing mode. In the second processing mode, when the first time is between 200ns and 600ns, the range of the second time is 1ns~800ns, and when the first time is not less than 600ns, the range of the second time is 800ns~1200ns. A wire cutting rough machining electrical waveform modulation method as described in claim 1, wherein the control module can switch to a carbon deposition processing mode. In the carbon deposition processing mode, when the first time is between 200ns and 600ns, the second time ranges from 1ns to 600ns, and when the first time is not less than 600ns, the second time ranges from 600ns to 1200ns. A wire cutting rough machining electrical waveform modulation method as described in claim 1, wherein the first module has a first diode connected in series between the second electrode and the workbench, and a second diode and a first field effect transistor connected in parallel and in series between the first electrode and the workbench, and the second module has a third diode connected in series between the first electrode and the cutting copper wire, and a fourth diode and a second field effect transistor connected in parallel and in series between the first cutting copper wire and the second electrode. A wire cutting rough machining electrical waveform modulation method as described in claim 5, wherein the first electrode is the anode of the power source, the second electrode is the cathode of the power source, the anode of the first diode is electrically connected to the second electrode, the cathode of the second diode is electrically connected to the first electrode, the cathode of the third diode is electrically connected to the first electrode, the anode of the fourth diode is electrically connected to the second electrode, the source, drain and gate of the first field effect transistor are electrically connected to the first electrode, the workbench and the control module respectively, and the source, drain and gate of the second field effect transistor are electrically connected to the cutting copper wire, the second electrode and the control module respectively.