JPH06226538A - Electric discharge machine for split machining - Google Patents

Abstract

(57) [Summary] [Purpose] To be able to process multiple electrodes or workpieces with the same power source, obtain good surface roughness, and reduce electrode consumption. [Structure] Supplying processing power between a plurality of divided electrodes 2a, 2b, 2c provided in a processing liquid and a workpiece 3,
In an electric discharge machine that generates an electric discharge to machine the work piece 3 into the same shape as the electrodes 2a, 2b, 2c, the parallel bodies of the diodes 6a, 6b, 6c and the resistors 7a, 7b, 7c are connected in series. , Each electrode 2 through the parallel body
Processing power is supplied from the common power source 1 to a, 2b, and 2c.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric discharge machine for division machining, and more particularly to an electric discharge machine for division machining for simultaneously machining a workpiece by using a plurality of electrodes or a workpiece. It is about.

[0002]

2. Description of the Related Art The related art of this type of electric discharge machining apparatus for division machining is disclosed in Japanese Patent Laid-Open Nos. 58-59735 and 58-66629. The former is one that enables individual feed control of each electrode by controlling the engagement of a plurality of electrodes, and the latter is one that allows the divided parts of the electrodes to move independently relative to each other. It is disclosed.

FIG. 11 is a block diagram showing a conventional electric discharge machine. In the figure, 1 is a power source for supplying processing power, 2 is an electrode, 3 is a workpiece to be processed, 4 is a processing tank, 5
Is a working fluid in which water or oil is mainly used. In this electric discharge machine, the electrode 2 and the workpiece 3 are connected to a power source 1, and the electrode 2 and the workpiece 3 are immersed in a machining liquid 5 filled in a machining tank 4.

Next, the operation of the conventional electric discharge machine will be described. In the conventional electric discharge machine, the workpiece 3 is machined into the same shape as the electrode 2 by supplying machining electric power between the electrode 2 provided in the machining liquid 5 and the workpiece 3 to generate electric discharge. However, in the conventional electric discharge machining apparatus, when the gap between the electrode 2 and the workpiece 3 becomes narrower due to the dielectric constant of the machining fluid 5, the electrode 2 and the workpiece 3 rapidly increase in inverse proportion to the distance. The capacitance between the workpiece 3 and the workpiece 3 increases. Since the gap between the electrode and the work piece in the electric discharge machining is 1 to 20 μm, a considerably large capacitance exists between the electrode 2 and the work piece 3 when the area of the electrode becomes large. Further, this capacitance is inversely proportional to the area of the electrode 2. Therefore, when it is attempted to perform the electric discharge machining of the workpiece 3 with the electrode 2 having a large area, the amount of electricity accumulated in the capacitance of the gap causes
For example, if discharge occurs at point A in FIG. 11, the amount of electricity concentrates at point A and becomes inrush discharge energy, and a large current flows regardless of the current supplied from the power source 1, so the discharge energy Couldn't be smaller. As a result, the processed surface becomes rough, and the electrode 2 is consumed more.

[0005]

As described above, the conventional electric discharge machining apparatus for division machining has a problem that the surface to be machined of the workpiece becomes rough and the electrode wears out a lot. Was.

In order to improve this, FIG. 12 and FIG.
The method shown in (1) was also considered. FIG. 12 is a configuration diagram showing a conventional electric discharge machining device in which electrodes are divided.
FIG. 6 is a configuration diagram showing another conventional electric discharge machine. However, even if the electrodes 2a, 2b, 2c are divided as shown in FIG. 12, when discharge occurs at the point A of the electrode 2b, current flows from the electrodes 2a, 2c through the connected wiring as shown in the figure, and eventually Large rush energy was obtained, and only the roughness of the machined surface as in the case of the single electrode 2 in FIG. 11 was obtained. Also, as shown in FIG. 13, if the power supplies 1a, 1b, 1c are connected to the respective electrodes 2a, 2b, 2c, good results can be obtained, but the number of power supplies is the same as the number of electrodes. Therefore, there is a drawback that the device becomes expensive.

In view of the above, the present invention provides an electric discharge machining apparatus for division machining capable of machining a plurality of electrodes or workpieces with the same power source, obtaining good machined surface roughness, and reducing electrode consumption. The challenge is to provide.

[0008]

According to a first aspect of the present invention, there is provided an electric discharge machine for divided machining, in which machining electric power is supplied between a plurality of divided electrodes provided in a machining fluid and a workpiece to generate an electric discharge. In the electric discharge machining device for generating a workpiece and machining a workpiece into the same shape as an electrode, a diode is connected in series to each electrode, and machining power is supplied from a common power source.

According to a second aspect of the present invention, there is provided an electric discharge machining device for division machining in which machining electric power is supplied between an electrode provided in a machining fluid and a plurality of workpieces to be divided to generate an electric discharge. In an electric discharge machine for machining an object into the same shape as an electrode, a diode is connected in series to each object to be machined, and machining power is supplied from a common power source.

According to a third aspect of the present invention, there is provided an electric discharge machining apparatus for division machining in which a plurality of wire electrodes are moved in a machining liquid relative to a work piece, and machining power is applied between the wire electrodes and the work piece. In a wire-cut electric discharge machine that supplies electric power to generate an electric discharge to machine a workpiece into an arbitrary shape, a diode is connected in series to each wire electrode, and machining power is supplied from a common power source. is there.

According to a fourth aspect of the present invention, there is provided an electric discharge machining apparatus for division machining in which machining electric power is supplied between a plurality of divided electrodes provided in a machining fluid and a workpiece to generate an electric discharge, thereby machining the workpiece. In an electric discharge machine for machining an object into the same shape as an electrode, a parallel body of a diode and a resistor is connected in series to each electrode, and machining power is supplied from a common power source.

According to a fifth aspect of the present invention, there is provided an electric discharge machining device for division machining in which machining electric power is supplied between an electrode provided in a machining fluid and a plurality of workpieces to be divided to generate an electric discharge. In an electric discharge machine for machining an object into the same shape as an electrode, a parallel body of a diode and a resistor is connected in series to each object to be machined, and machining power is supplied from a common power source.

According to a sixth aspect of the present invention, there is provided an electric discharge machining apparatus for division machining in which a plurality of wire electrodes are moved relative to a work piece in a working fluid, and a machining power is applied between the wire electrodes and the work piece. In a wire-cut electric discharge machine that supplies electric current to generate an electric discharge to machine a workpiece into an arbitrary shape, a parallel body of a diode and a resistor is connected in series to each wire electrode, and machining is performed from a common power source. It supplies electric power.

[0014]

In the electric discharge machining apparatus for division machining according to the first aspect of the invention, the diodes are connected in series to the plurality of electrodes, respectively, and the machining power is supplied from the common power source. When one of the electrodes discharges, the other diode is in the reverse bias state, the amount of electricity stored in the other electrode does not flow into the electrode, and the rush discharge energy of each electrode becomes small.

In the electric discharge machining device for division machining according to the second aspect of the present invention, the diodes are connected in series to the plurality of workpieces and the machining power is supplied from the common power source. Even when one of the workpieces is discharged, the other diode is reverse-biased, the quantity of electricity stored in the other workpiece does not flow into the workpiece, and the rush discharge energy of each workpiece Becomes smaller.

In the electric discharge machining apparatus for split machining according to the third aspect of the invention, the diodes are connected in series to the plurality of wire electrodes for wire cut electric discharge machining, and the machining power is supplied from the common power source. , When one of the multiple wire electrodes discharges, the other diode is reverse-biased, and the amount of electricity stored in the other wire electrode does not flow into that wire electrode, causing inrush discharge of each wire electrode. Energy becomes smaller.

In the electric discharge machining device for division machining of the fourth aspect of the invention, the parallel body of the diode and the resistor is connected in series to the plurality of electrodes, and the machining power is supplied from the common power source. Even when one of the plurality of electrodes is discharged, the other diode is in the reverse bias state, the quantity of electricity stored in the other electrode does not flow into that electrode, and the rush discharge energy of each electrode becomes small.

In the electric discharge machining apparatus for division machining according to the fifth aspect of the invention, a parallel body of a diode and a resistor is connected in series to a plurality of workpieces, and machining power is supplied from a common power source. Therefore, even when one of the plurality of workpieces is discharged, the other diode is reverse-biased, and the amount of electricity stored in the other workpiece does not flow into the workpiece, and Inrush discharge energy of the work piece becomes small.

In the electric discharge machining apparatus for division machining of the sixth aspect of the present invention, a parallel body of a diode and a resistor is connected in series to a plurality of wire electrodes for wire cut electric discharge machining, and machining power is supplied from a common power source. Since it is supplied, even when one of the multiple wire electrodes is discharged,
The other diodes are reverse-biased, the amount of electricity stored in the other wire electrode does not flow into the wire electrode, and the rush discharge energy of each wire electrode becomes small.

[0020]

Embodiments of the present invention will be described below. <First Embodiment> FIG. 1 is a block diagram showing an electric discharge machining apparatus for division machining according to a first embodiment of the present invention. In the figure, the same reference numerals and symbols as those of the above-mentioned conventional example indicate the same or corresponding components as those of the above-mentioned conventional example. In the figure, 6a, 6
b and 6c are diodes, and these diodes 6a and 6c
b and 6c are divided into a plurality of parts and are connected in series to the respective electrodes 2a, 2b and 2c which are insulated from each other.

FIG. 2 is a circuit diagram showing a circuit electrically equivalent to the electric discharge machining apparatus for division machining of FIG. 1, FIG. 3 is a waveform diagram showing the relationship between voltage and current of the electric discharge machining apparatus for division machining of FIG. It is a time chart, (a) shows the voltage of the discharge point A of FIG. 2, (b) shows the electric current of the discharge point A of FIG. The operation of the electric discharge machining device for split machining of FIG. 1 will be described with reference to these drawings. When the switch 9 connected to the voltage source 8 of the power source 1 is turned on, a voltage is applied between the electrodes through the resistor 10. The voltage of the voltage source 8 is set to about 80 volts, and the diode 11 is connected in parallel to the series body of the voltage source 8 and the switch 9.

When a current flows in the forward direction of the diodes 6a, 6b, 6c, the voltage 12 between the electrodes rises and reaches the voltage 14 of the voltage source 8 as shown in FIG. 3 (a). At this time, the capacitances Ca, Cb, Cc between the respective electrodes 2a, 2b, 2c and the work piece 3 are charged with electricity.

Next, when an electric discharge is generated at the electric discharge point A, the voltage 13 between the electrode 2b and the workpiece 3 is rapidly lowered to the electric discharge voltage 15, and the electric quantity of the electrostatic capacitance Cb flows. This state is the inrush current 16 shown in (b). Then, from the power source 1 to the electrodes 2a, 2b, 2c or the workpiece 3
A current 17 determined by the wiring inductance 18 and the resistor 10 flows.

At the moment when the discharge is generated at the discharge point A, no discharge is generated at the other electrodes.
The amounts of electricity stored in the capacitors Ca and Cc are the diodes 6a and 6c connected in series to the electrodes 2a and 2c, respectively.
A voltage is applied in the opposite direction, but no current flows. There are high-speed switching diodes such as high-speed recovery diode and Schottky barrier diode in this diode, and the junction capacitance of itself is small,
High current products are on sale. They can also be used for fast current changes in electrical discharge machining.

As described above, the electric discharge machining apparatus for division machining according to the present embodiment includes a plurality of electrodes 2a, 2b, for machining the workpiece 3 by generating an electric discharge between the workpiece 3 and the workpiece 3 in the machining liquid. 2c
And diodes 6a, 6b, 6c connected in series to the plurality of electrodes 2a, 2b, 2c, and the electrodes 2a, 2b, 2 via the diodes 6a, 6b, 6c.
A common power supply 1 for supplying processing power to c is provided.

That is, the electric discharge machining apparatus for division machining of this embodiment is provided with a plurality of divided electrodes 2a, which are provided in the machining fluid.
2d, 2c and the workpiece 3 are supplied with machining power to generate an electric discharge to machine the workpiece 3 into the same shape as the electrodes 2a, 2b, 2c.
6b and 6c are connected in series to the respective electrodes 2a, 2b and 2c, and processing power is supplied from a common power source 1.

Therefore, the plurality of electrodes 2a, 2b, 2c
When one of them discharges, the corresponding diode 6
a, 6b, 6c are in the forward bias state, and the other diodes 6a, 6b, 6c are in the reverse bias state,
The amount of electricity stored in another electrode does not flow into that electrode,
Since the inrush discharge energy of each electrode is small, a plurality of electrodes can be processed with the same power source. Therefore, when a large electrode is divided into a plurality of small electrodes, a good processed surface can be obtained as compared with the case where a single large electrode is used for processing.
Further, since the machining can be performed with the same power source and the inrush discharge energy is small, the electrode consumption is small and the apparatus can be inexpensive.
In addition, since the roughness of the machined surface does not deteriorate even if a plurality of parts are machined at the same time, a plurality of parts can be machined at the same time, and labor saving of the process can be promoted. By performing simultaneous processing in this manner, a relative error in machine accuracy is eliminated, and high-accuracy processing can be realized.

<Second Embodiment> FIG. 4 is a block diagram showing an electric discharge machining apparatus for division machining according to a second embodiment of the present invention. In the figure, the same reference numerals and symbols as those of the first embodiment indicate the same or corresponding components as those of the first embodiment. In the figure, 6a, 6b and 6c are diodes, and 7a and 7c.
b and 7c are resistors respectively connected in parallel with the respective diodes 6a, 6b and 6c, and the parallel body of the diodes 6a, 6b and 6c and the resistors 7a, 7b and 7c is divided into a plurality of parts, which are isolated from each other. The electrodes 2a, 2b and 2c are connected in series.

FIG. 5 is a circuit diagram showing a circuit electrically equivalent to the electric discharge machining apparatus for division machining of FIG. 4, FIG. 6 is a waveform diagram showing the relationship between voltage and current of the electric discharge machining apparatus for division machining of FIG. 5 is a time chart, (a) shows the voltage at discharge point A in FIG. 5, and (b) shows the current at discharge point A in FIG. The electric discharge machining apparatus for division machining shown in FIG. 4 basically operates in the same manner as in the first embodiment. When the switch 9 of the power supply 1 is turned on, a voltage is applied between the electrodes and the diodes 6a, 6
A current flows in the forward direction of b and 6c, the voltage 12 between the electrodes rises and reaches the voltage 14 of the voltage source 8 as shown in FIG. At this time, the capacitances Ca, Cb, Cc between the respective electrodes 2a, 2b, 2c and the work piece 3 are charged with electricity.

When a discharge is generated at the discharge point A, the voltage 13 between the electrode 2b and the work piece 3 rapidly drops to the discharge voltage 15, the quantity of electricity of the electrostatic capacitance Cb flows, and a predetermined wiring inductance 18 is generated. A current 17 determined by the resistor 10 flows. At the moment when the discharge is generated at the discharge point A, no discharge is generated at the other electrodes 2a and 2c, so that the amounts of electricity stored in the capacitors Ca and Cc are opposite to the diodes 6a and 6c. Takes.

However, in this embodiment, the resistors 6a, 7b and 7c are connected in parallel to the diodes 6a, 6b and 6c, respectively. Moreover, these resistors 7a, 7b,
7c is set to be larger than the resistance 10 of the power supply 1, its discharge current is small, and the voltage 19 of the capacitors Ca and Cc decreases as shown by the broken line in FIG. Therefore, the amount of electricity stored in the capacitors Ca and Cc does not rapidly flow into the discharge point A, so that the rush current does not increase. In the case of the conventional electric discharge machining device without a diode, the entire amount of electricity flows in as shown by the broken line 20 in FIG. 6B, the rush discharge energy increases, and the machining surface of the workpiece 3 becomes rough. Will end up. The resistors 7a, 7 connected in parallel to the diodes 6a, 6b, 6c
It is desirable that b and 7c are wired in the shortest distance and are non-inductive resistors.

In the first embodiment, the diode 6
When an overvoltage is applied to a, 6b, and 6c, the diode 6
It was easy to damage a, 6b, and 6c. However, in this embodiment, even if an overvoltage is applied to the diodes 6a, 6b, 6c, the resistors 7a, 7b, 7c have an effect of absorbing this overvoltage.

As described above, the electric discharge machining apparatus for division machining according to the present embodiment, the plurality of electrodes 2a, 2b, for machining the workpiece 3 by generating an electric discharge between the workpiece 3 and the workpiece 3 in the machining liquid. 2c
And diodes 6a, 6b, 6c and resistors 7a, 7b, which are connected in series to the plurality of electrodes 2a, 2b, 2c, respectively.
7c in parallel with each of the diodes 6a, 6b, 6c
And a resistor 7a, 7b, 7c in parallel, and a common power source 1 for supplying processing power to each of the electrodes 2a, 2b, 2c.

That is, the electric discharge machining apparatus for division machining of this embodiment is obtained by adding resistors 7a, 7b, 7c to the first embodiment, and is divided into a plurality of divided electrodes 2a provided in the machining fluid. , 2b, 2c are connected in series with parallel bodies of diodes 6a, 6b, 6c and resistors 7a, 7b, 7c, respectively, and processing power is supplied from a common power supply 1.

Therefore, the plurality of electrodes 2a, 2b, 2c
Even when one of the electrodes is discharged, the amount of electricity stored in the other electrode does not flow into that electrode, and the rush discharge energy of each electrode becomes small, so that the plurality of electrodes 2a, 2b,
2c can be processed with the same power supply 1. Therefore, also in the present embodiment, the same effect as the first embodiment can be obtained, a large electrode can be divided and processed by a plurality of small electrodes, and a good processing surface compared to the case of processing by a single large electrode. Is obtained. Further, like the first embodiment, the electrode consumption is small, the apparatus can be made inexpensive, the labor saving of the process can be promoted, and highly accurate processing can be realized. In particular, in this embodiment,
Even when an overvoltage is applied to the diodes 6a, 6b, 6c, the resistors 7a, 7b, 7c have an action of absorbing the overvoltage, so that the diodes 6a, 6b, 6c can be prevented from being damaged and reliability is improved.

FIG. 7 is a block diagram showing a case where the electric discharge machining device for division machining has a contact detection circuit function. In the figure, 21 is a voltage source, 22 is a high resistance connected to the voltage source 21, and 23 is a voltage between CDs. This is the case where the power supply 1 has a circuit having a function of contact detection.

This electric discharge machining device for division machining is provided with a voltage source 2
1 is connected to a high resistance 22 of about 10 KΩ, and electrodes 2a, 2
b, 2c and the voltage 23 of the workpiece 3 are monitored, and the electrodes 2a,
The contact between the electrode and the workpiece is detected by utilizing that the voltage 23 becomes zero when the workpieces 2b and 2c and the workpiece 3 come into contact with each other, for example, at a point B. However, the resistors 7a, 7 connected in parallel to the diodes 6a, 6b, 6c, respectively.
When b and 7c are considerably smaller than the high resistance 22, the voltage 23 becomes close to zero regardless of which of the electrodes 2a, 2b and 2c contacts the work piece 3, so that the detection incorporated in the power supply 1 is performed. Even if the detector is used, there is an advantage that the detection voltage does not need to be changed.

As shown in FIG. 1, the electrodes 2a, 2b,
If only the diodes 6a, 6b, 6c are connected to 2c and there is no resistance, the detection voltage needs to be changed because it does not drop below the forward voltage (about 0.6 volt) of the diodes 6a, 6b, 6c. . In addition, the diodes 6a, 6b,
Since the forward voltage of 6c changes with temperature, the detection accuracy cannot be increased.

<Third Embodiment> FIG. 8 is a block diagram showing an electric discharge machining apparatus for division machining according to a third embodiment of the present invention. In the figure, the same reference numerals and symbols as those of the above-mentioned respective embodiments indicate the same or corresponding constituent parts as those of the above-mentioned respective embodiments. In the figure, 3a, 3b, and 3c are workpieces divided into a plurality of pieces. In the electric discharge machine for division machining of this embodiment, the electrode 2
Not only a, 2b, and 2c, but also the work pieces 3a, 3b, and 3c whose mutual insulation is maintained. Then, the diodes 6a, 6b, 6 are connected to the plurality of electrodes 2a, 2b, 2c.
c are connected in series, and processing power is supplied from a common power source 1.

Therefore, as in the first embodiment, even when one of the plurality of electrodes discharges, the amount of electricity stored in the other electrode does not flow into that electrode, and the rush discharge energy of each electrode does not flow. Becomes smaller, the same effect as the first embodiment can be obtained.

Resistors 7a, 7b and 7c are connected in parallel to the diodes 6a, 6b and 6c as shown by broken lines in the figure, and the diodes 6a, 6b and 6c and the resistors 7a and 7c are connected.
If the parallel body with b and 7c is connected in series to each of the plurality of electrodes 2a, 2b and 2c and the processing power is supplied from the common power source 1, the same operation and effect as the second embodiment can be obtained.
In particular, even when an overvoltage is applied to the diodes 6a, 6b, 6c, the resistors 7a, 7b, 7c have an action of absorbing the overvoltage, so that the diodes 6a, 6b, 6c can be prevented from being damaged and the reliability is improved. To do.

Furthermore, the electrodes 2a, 2b and 2c and the workpieces 3a and 3b, respectively, are placed in different positions or in different processing tanks.
Even if there is 3c, there is an effect that processing is possible.
Therefore, different parts can be simultaneously subjected to electrical discharge machining using different electrodes.

<Fourth Embodiment> FIG. 9 is a block diagram showing an electric discharge machining apparatus for division machining according to a fourth embodiment of the present invention. In the figure, the same reference numerals and symbols as those of the above-mentioned respective embodiments indicate the same or corresponding constituent parts as those of the above-mentioned respective embodiments. As shown in the figure, the electric discharge machining apparatus for division machining according to the present embodiment is divided into a plurality of pieces provided in a machining liquid, and the workpieces 3a, 3b, 3c are insulated from each other, and the diodes 6a, 6b, 6
c are connected in series, and processing power is supplied from a common power source 1.

Therefore, a plurality of workpieces 3a, 3b,
Even when one of 3c is discharged, another workpiece 3
The quantity of electricity stored in a, 3b, and 3c is the workpiece 3
a, 3b, 3c without flowing into the respective work pieces 3a, 3
The inrush discharge energy of b and 3c becomes small. Therefore, a plurality of workpieces 3a, 3b, 3c can be processed by the same power source 1, and a large workpiece can be divided into a plurality of small workpieces 3a, 3b, 3c. As a result, similarly to the first embodiment, the electrode consumption is small, the apparatus can be made inexpensive, the labor saving of the process can be promoted, and highly accurate processing can be realized.

Further, resistors 7a, 7b and 7c are connected in parallel to the diodes 6a, 6b and 6c as shown by broken lines in the figure, and the diodes 6a, 6b and 6c and the resistors 7a and 7c are connected.
b, 7c in parallel with a plurality of workpieces 3a, 3b, 3c
If the processing power is supplied from the common power source 1 by connecting them in series with each other, the same operation and effect as those of the second embodiment can be obtained. In particular, even when an overvoltage is applied to the diodes 6a, 6b, 6c, the resistors 7a, 7b, 7c have an action of absorbing the overvoltage, so that the diodes 6a, 6b, 6c can be prevented from being damaged and the reliability is improved. To do.

Further, although the electrode 2 is integrated here, the same effect can be obtained even if the electrode 2 is divided into a plurality of parts according to the workpieces 3a, 3b, 3c.

<Fifth Embodiment> FIG. 10 is a block diagram showing an electric discharge machining device for division machining according to a fifth embodiment of the present invention.
In the figure, the same reference numerals and symbols as those of the above-mentioned respective embodiments indicate the same or corresponding constituent parts as those of the above-mentioned respective embodiments. In the figure, 24a, 24b and 24c are in the working fluid,
The workpiece 3 is moved relative to the workpiece 3,
And a plurality of wire electrodes 25a, 25b, 25c for processing the workpiece 3 by generating an electric discharge between
4a, 24b, 24c, which are in contact with each other and are electrically connected to the power supply 1. During processing, the contacts 25a, 25b, 25c are in series contact with the wire electrodes 24a, 24b, 24c, which are always sent in sequence. The diode 6 is attached to each wire electrode 24a, 24b, 24c.
Processing power is supplied from a common power source 1 by connecting a, 6b, and 6c in series.

As described above, the electric discharge machining apparatus for division machining according to the present embodiment is moved in the machining liquid relative to the work piece 3 to generate an electric discharge between the work piece 3 and the work piece 3. A plurality of wire electrodes 24a, 24 for processing the workpiece 3 by
b, 24c and the plurality of wire electrodes 24a, 24b,
Diodes 6a, 6b, connected in series to 24c,
6c and a common power source 1 for supplying processing power to the wire electrodes 24a, 24b, 24c via the diodes 6a, 6b, 6c.

That is, the electric discharge machining apparatus for division machining of the present embodiment has a plurality of wire electrodes 24 for wire cut electric discharge machining.
Diodes 6a, 6b and 6c are connected in series to a, 24b and 24c, respectively, and processing power is supplied from a common power source 1.

Therefore, a plurality of wire electrodes 24a, 2
Even when one of 4b and 24c is discharged, the amount of electricity stored in the other wire electrode does not flow into the wire electrode, and the rush discharge energy of each wire electrode 24a, 24b, and 24c becomes small. The same effect as the first embodiment is obtained. In particular, if applied to a wire-cut electric discharge machine as in this embodiment, a plurality of wire electrodes 2
Since the workpiece 3 can be simultaneously processed by 4a, 24b, and 24c, it is not necessary to replace the wire electrodes 24a, 24b, and 24c, and the processing can be performed in a short time. As a result, labor saving in the process can be promoted and highly accurate processing can be realized.

Further, resistors 7a, 7b and 7c are connected in parallel to the diodes 6a, 6b and 6c as shown by broken lines in the figure, and the diodes 6a, 6b and 6c and the resistors 7a and 7c are connected.
b, 7c in parallel with a plurality of wire electrodes 24a, 24
If the processing power is supplied from the common power source 1 by connecting to b and 24c in series, the same operation as in the second embodiment,
Produce an effect. Especially, when an overvoltage is applied to the diodes 6a, 6b, 6c, this overvoltage is applied to the resistors 7a, 7c.
b and 7c have an absorbing effect, the diode 6a,
The damage of 6b and 6c can be prevented, and the reliability is improved. Even in this case, the plurality of wire electrodes 24a, 24b,
Since the workpiece 3 can be simultaneously processed by 24c, the wire electrodes 24a, 24b, 24c do not need to be replaced and the processing can be performed in a short time.

When the present invention is carried out, the diodes connected in series on the discharge side are forward biased,
Since it suffices that the diode connected in series which is not on the other discharge side is reverse biased, the position of the circuit in which the diode is inserted may be a position where the power source, the electrode and the workpiece are in series.

[0053]

As described above, the electric discharge machining apparatus for split machining according to the invention of claim 1 has a plurality of electrodes for machining a workpiece, diodes connected in series to the respective electrodes,
A common power supply for supplying processing power to each electrode is provided, and a diode is connected in series to each of the plurality of electrodes, and processing power is supplied from the common power supply, so that when one of the plurality of electrodes is discharged, The diode inserted in series with the other circuit is in the reverse bias state, the amount of electricity stored in the other electrode does not flow into that electrode, and the inrush discharge energy of each electrode becomes small, so multiple electrodes are the same. It can be processed with the power source, the electrode consumption is small, and the device can be inexpensive. Moreover, labor saving of the process can be promoted, and by performing the machining at the same time, the relative error of the machine precision is eliminated, and the high precision machining can be realized.

According to a second aspect of the present invention, there is provided an electric discharge machining apparatus for division machining, electrodes for machining a plurality of workpieces, diodes connected in series to each workpiece, and machining power to each workpiece. And a common power source for supplying the same, the diodes are respectively connected in series to the plurality of workpieces, and the processing power is supplied from the common power source, so that when one of the plurality of workpieces is discharged, the other The diodes inserted in series in the circuit are in the reverse bias state, the amount of electricity stored in other workpieces does not flow into the workpiece, and the inrush discharge energy of each workpiece becomes small. The workpiece can be processed with the same power source, the electrode consumption is small, and the device can be inexpensive. Moreover, the labor saving of the process can be promoted, and by processing at the same time, the relative error of the machine accuracy is eliminated,
High-precision processing can be realized.

According to a third aspect of the present invention, there is provided an electric discharge machining apparatus for split machining, in which a plurality of wire electrodes for machining a workpiece, diodes connected in series to the respective wire electrodes, and machining power are supplied to the respective wire electrodes. When a wire is discharged from one of the plurality of wire electrodes by connecting a diode to each of the plurality of wire electrodes for wire cut electric discharge machining in series and supplying machining power from the common power source. , The diode inserted in series in the other circuit is in the reverse bias state, the amount of electricity stored in the other wire electrode does not flow into that wire electrode, and the inrush discharge energy of each wire electrode becomes small, Wire electrodes can be processed with the same power source. Moreover, since the machining can be performed in a short time without replacing the wire electrode, labor saving of the process can be promoted and highly precise machining can be realized.

According to a fourth aspect of the present invention, there is provided an electric discharge machining apparatus for division machining in which a plurality of electrodes for machining a workpiece, a parallel body of a diode and a resistor connected in series to each electrode, and each electrode are machined. A common power source for supplying electric power is provided, and a parallel body of a diode and a resistor is connected in series to a plurality of electrodes, and processing power is supplied from the common power source, whereby one of the plurality of electrodes is discharged. At this time, the diode inserted in series in the other circuit is in the reverse bias state, the quantity of electricity stored in the other electrode does not flow into that electrode, and the rush discharge energy of each electrode becomes small, so Can be processed with the same power source, electrode consumption is low, and the device can be inexpensive. Moreover, the labor saving of the process can be promoted,
By performing the processing at the same time, the relative error of the machine accuracy is eliminated, and the highly accurate processing can be realized. Further, since the resistor absorbs the overvoltage applied to the diode, damage to the diode can be prevented and reliability is improved.

According to a fifth aspect of the present invention, there is provided an electric discharge machining apparatus for division machining, an electrode for machining a plurality of workpieces, a parallel body of a diode and a resistor connected in series to each workpiece, and each workpiece. A plurality of workpieces are connected by connecting a parallel body of a diode and a resistor in series to a plurality of workpieces, and a common power source is used to supply processing power to the workpieces. When one of the workpieces is discharged, the diode inserted in series in the other circuit is in the reverse bias state, and the amount of electricity stored in the other workpiece does not flow into the workpiece, and the respective workpieces are not charged. Since the rush discharge energy of the workpiece is small, a plurality of workpieces can be processed with the same power source, the electrode consumption is small, and the apparatus can be inexpensive. Moreover, labor saving of the process can be promoted, and by performing the machining at the same time, the relative error of the machine precision is eliminated, and the high precision machining can be realized. Further, since the resistor absorbs the overvoltage applied to the diode, damage to the diode can be prevented and reliability is improved.

According to a sixth aspect of the present invention, there is provided an electric discharge machining apparatus for split machining, a plurality of wire electrodes for machining a workpiece, a parallel body of a diode and a resistor connected in series to each wire electrode, and each wire. A common power supply for supplying machining power to the electrodes is provided, and a parallel body of a diode and a resistor is connected in series to a plurality of wire electrodes for wire cut electric discharge machining,
By supplying the processing power from the common power source, when one of the plurality of wire electrodes is discharged, the diode inserted in series with the other circuit is in the reverse bias state,
The amount of electricity stored in another wire electrode does not flow into that wire electrode, and the rush discharge energy of each wire electrode becomes small, so that a plurality of wire electrodes can be processed with the same power source. Moreover, since the machining can be performed in a short time without replacing the wire electrode, labor saving of the process can be promoted and highly precise machining can be realized. Further, since the resistor absorbs the overvoltage applied to the diode, damage to the diode can be prevented and reliability is improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an electric discharge machining device for division machining according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a circuit electrically equivalent to the electric discharge machining apparatus for division machining of FIG.

FIG. 3 is a waveform diagram and a time chart showing the relationship between voltage and current in the electric discharge machine for division machining of FIG.

FIG. 4 is a configuration diagram showing an electric discharge machining device for division machining according to a second embodiment of the present invention.

FIG. 5 is a circuit diagram showing a circuit electrically equivalent to the electric discharge machining device for division machining of FIG.

6 is a waveform chart and a time chart showing the relationship between voltage and current in the electric discharge machine for division machining of FIG.

FIG. 7 is a configuration diagram showing a case where the electric discharge machining device for division machining of the present invention has a contact detection circuit function.

FIG. 8 is a block diagram showing an electric discharge machine for division machining which is a third embodiment of the present invention.

FIG. 9 is a block diagram showing an electric discharge machining device for division machining according to a fourth embodiment of the present invention.

FIG. 10 is a block diagram showing an electric discharge machining device for division machining which is a fifth embodiment of the present invention.

FIG. 11 is a configuration diagram showing a conventional electric discharge machine.

FIG. 12 is a configuration diagram showing a conventional electric discharge machining apparatus in which electrodes are divided.

FIG. 13 is a configuration diagram showing another conventional electric discharge machining apparatus.

[Explanation of symbols]

 1, 1a, 1b, 1c Power source 2, 2a, 2b, 2c Electrode 3, 3a, 3b, 3c Workpiece 4 Processing tank 5 Working fluid 6a, 6b, 6c, 11 Diode 7a, 7b, 7c, 10, 22 Resistance 8,21 Voltage source 9 Switch 18 Inductance 24a, 24b, 24c Wire electrode 25a, 25b, 25c Contactor Ca, Cb, Cc Capacitance

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[Procedure amendment]

[Submission date] July 22, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 2

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction content]

Next, the operation of the conventional electric discharge machine will be described. In the conventional electric discharge machine, the workpiece 3 is machined into the same shape as the electrode 2 by supplying machining electric power between the electrode 2 provided in the machining liquid 5 and the workpiece 3 to generate electric discharge. However, in the conventional electric discharge machining apparatus, when the gap between the electrode 2 and the workpiece 3 becomes narrower due to the dielectric constant of the machining fluid 5, the electrode 2 and the workpiece 3 rapidly increase in inverse proportion to the distance. The capacitance between the workpiece 3 and the workpiece 3 increases. Since the gap between the electrode and the work piece in the electric discharge machining is 1 to 20 μm, a considerably large capacitance exists between the electrode 2 and the work piece 3 when the area of the electrode becomes large. Further, this capacitance is proportional to the area of the electrode 2 . Therefore, when an electric discharge machining of the workpiece 3 is performed with the electrode 2 having a large area,
For example, if discharge occurs at point A in FIG. 11 due to the amount of electricity stored in the capacitance of the gap, the amount of electricity concentrates at point A and becomes inrush discharge energy, and the power source 1
The discharge energy could not be reduced because a large current would flow regardless of the current supplied from. As a result, the processed surface becomes rough, and the electrode 2 is consumed more.

Claims (6)

[Claims] 1. A plurality of electrodes for machining an object to be machined by generating an electric discharge between the electrode and the object to be machined in a machining liquid, and the electrodes of the plurality of electrodes are insulated from each other. And a common power source for supplying machining power to each of the electrodes via the diodes, and an electric discharge machine for division machining. 2. An electrode for processing each workpiece by generating an electric discharge between each of the plurality of workpieces in a working liquid, and an insulating state between each electrode of the plurality of electrodes, and each of them An electric discharge machining device for division machining, comprising: a diode connected in series to the electrode of 1); and a common power source for supplying machining power to each of the workpieces via the diode. 3. A plurality of wire electrodes, which move in a working liquid relative to a work piece to generate an electric discharge between the work electrode and the work piece, and a plurality of the wire electrodes. Each wire electrode of the wire electrodes is in an insulated state, and a diode connected in series to each of the wire electrodes and a common power source for supplying processing power to each of the wire electrodes via each of the diodes are provided. An electric discharge machining device for division machining, characterized by: 4. A plurality of electrodes for machining an object to be processed by generating an electric discharge between the electrode and the object to be processed in a working liquid, and the electrodes of the plurality of electrodes are insulated from each other. And a parallel body composed of a diode and a resistor connected in series with respect to each other, and a common power source for supplying machining power to each of the electrodes through the parallel body. . 5. An electrode for machining each workpiece by generating an electric discharge between the workpiece and a plurality of workpieces in a working liquid, and an insulating state between the workpieces of the plurality of workpieces. A parallel body composed of a diode and a resistor connected in series to each of the workpieces, and a common power supply for supplying machining power to each of the workpieces through the parallel bodies. The electric discharge machine for split machining characterized by. 6. A plurality of wire electrodes for moving a workpiece in a working liquid relative to the workpiece to generate an electric discharge between the workpiece and the wire electrode, and the plurality of wire electrodes. The wire electrodes of the wire electrodes are insulated from each other, and a parallel body composed of a diode and a resistor connected in series to each of the wire electrodes, and processing power is supplied to the wire electrodes via the parallel body. An electric discharge machining apparatus for division machining, comprising: