SU1411935A1 - Electro-erosion machining apparatus - Google Patents

Abstract

The invention can be used as a current source for copy-stitching and final machines. The purpose of the invention is to improve the reliability of the device. The device contains a power source 1, thyristors 2 and 8, inductors 3 and 9, diodes 5 and 6 and capacitors (K) 4, 10 and 11. During the working condition and short circuit of the erosion gap (P ) 7 one of K 4 or 10 is turned on in parallel with П 7, and the second is sequentially connected with K 10, shunted diode 6. By increasing the capacitance, shunt ring of P 7, the process efficiency increases and the current is limited during short circuit of P 7. 1 sludge. .

Description

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The invention relates to erosion treatment and can be used as a power source for copying and piercing and cutting machines.

The purpose of the invention is to increase the reliability of the device.

The drawing shows an electrical schematic diagram of the device.

The device for electrical discharge machining contains a power source 1, the positive bus of which is connected to the anode of the first thyristor 2, the cathode of which is connected through the first inductor 3 connected in series and the first capacitor 4 to the anode of the first 5 and the cathode of the second 6 diodes, the cathode of the first 5 and the anode Secondly-20 pry 6 diodes are connected to the corresponding electrodes of the erosion gap 7, the second thyristor 8, the second choke 9, the second 10 and the third 11

capacitors, the first pins 25 of the first 4 and second 10 capacitors are connected to the corresponding electrodes of the erosion gap 7, the second pins of the first 4 and second 10 capacitors are interconnected by

and through the third capacitor 11 pf

Connected to the negative bus of power supply 1 and the cathode of the second thyristor 8, the anode of which is connected via the second choke 9 to the first output of the second capacitor 10.

The device works as follows.

If the first control pulse is applied to the thyristor 8, then the Q state of the device circuit does not change.

When a control pulse is applied to the thyristor 2, the latter, when unlocked, generates a charging current for storage capacitors 4 and 11. In the case of a breakdown from an erosion gap 7, the storage capacitor 4 generates a current for the erosion gap through diode 6. At the end of the charging of the storage capacitor 11 and the storage capacitor 4 (the latter is charged only in the absence of a breakdown of the erosion gap) thyristor 2 is closed. Locking occurs due to the reverse voltage generated by the oscillatory nature of the process due to low active losses in the circuit. A control pulse is then applied to the thyristor 8, which

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unlocked, it creates a recharge current of the storage capacitor 11 and charging of the storage capacitor 10. In the case of an erosion gap 7, the storage capacitor 10 is discharged through diode 5. The storage capacitor 10 is discharged and recharged to reverse voltage polarity this causes the thyristor 8 to turn off. In the event of an erosion gap of 7, the storage capacitors 4 and 10 are charged before the voltage indicated on the polarity circuit. Charging continues until the voltages on the storage capacitors 4, 10, and 11 become the same, or there are no conditions for turning on the thyristors 2 and 8. This will happen when the sum of the voltages on the storage capacitors 4 and 11 becomes equal to the power supply (for thyristor 2) and for thyristor 8, and the sum of the voltages on the storage capacitors 10 and 11 will reach zero.

If a storage capacitor 4 is selected with a smaller storage capacitor 10, the conditions for closing the thyristor 2 will be earlier than for the thyristor 8, which will continue to work until the conditions for its closure appear. In this case, for any changes in the state of erosion, conditions for breaking the inversion of the device will not be created, the device has increased reliability.

In addition, since the proposed device does not consume current at idle and does not have a shunting element, its efficiency is significantly higher (by a factor of 2–3) than the known one. At idle, the sum of the voltages of the storage capacitors 4 and 10 is applied to the erosion gap for as long as there is no breakdown of the erosion gap, which in the proposed device can occur at any time. The erosion gap is shunted by two storage capacitors 4 and 10 connected in series, so that their total capacitance is lower, which makes it possible to form a shorter current pulse with a steep leading edge and greater amplitude.

In the working state and short erosion gap, one of the storage capacitors 4 or 10 is connected in parallel to the erosion gap 7, and the second is in series with the second storage capacitor 10, shunted by the diode 6. By increasing the capacity of the shunting erosion gap 7, the process efficiency increases The current is limited when the erosion gap is short-circuited.

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Claims (1)

Invention Formula An electroerosive processing device containing a power source, the positive bus of which is connected to the anode of the first thyristor, the cathode of which is connected through serially connected first  The choke and the first capacitor to the anode of the first and the cathode of the second diode are the cathode of the first and the anode of the second diode connected to the corresponding electrodes of the erosion gap, the second thyristor, characterized in that, in order to increase the reliability of the device, a second choke, second and third capacitors are inserted into it, wherein the first terminals of the first and second capacitors are connected to the corresponding electrodes of the erosion gap, the second terminals of the first and second capacitors are connected to each other and through the third capacitor along Keys to the negative bus of the power supply, the cathode of the second thyristor, -anode of which is connected through the second choke with the first output of the second capacitor.