SU399326A1 - DEVICE FOR CONDENSING WELDING - Google Patents

Description

one

The invention relates to devices for capacitor welding of H1 Series: essentially small parts and can be applied, for example, in butt welding with resistance of the housing leads of the resistors and diodes, axial leads of resistors and capacitors, with resistance welding and welding. from ferrous and non-ferrous metals in electronic, instrument-making and machine-building industrial enterprises.

Devices for capacitor welding are known, consisting of a rectifier, a circuit of series-connected charge thyristor and a limiting resistor, operating capacitors, a voltage divider parallel connected to: a capacitor, m, a discharge valve, a welding transformer, and a control unit. house of working capacitors.

However, for these devices, the accuracy of voltage stabilization on the working capacitors is characteristic, and with an increase in stabilization accuracy, the productivity of the welding machine decreases.

The purpose of the invention is to improve the accuracy of voltage stabilization on the working capacitors without reducing the productivity of the welding machine.

This is achieved by the fact that the circuit of series-connected charge thyristor

and a current limiting resistor 1 is connected in parallel with a circuit consisting of similar series-connected elements, with the resistance of the connected resistor being many times greater than the resistance of the resistor, the interrupter is connected to the control electrode circuit of the charge thyristor.

On fa-ir. 1 shows a diagram of the proposed device. For capacitor welding; on fi1g. 2-plots of the device operation processes (where Us is the charging voltage, UK is the voltage on the working capacitors, t / ass setpoint voltage l.

The device contains a charging transformer I, a charging rectifier 2 assembled by a bridge circuit, current-limiting resistors 3 and 4 (and the resistance of resistor 3 is many times greater than the resistance of resistor 4), charging tirpstor 5 and b, capacitor bank 7, divider 8 voltage, connected in parallel with operating capacitors 7, discharge valve 9, welding transformer 10, stabilized charge control unit 11, interrupter 12 in the thyristor control circuit 6.

B.LOCK 11 control stabilization charge, up to m, in accordance with the signal coming from divider voltage 8, produces thyristor control signals 5 and 6. Block 11 is connected to the control circuit tiipiHCTOpOB 5 and b at the beginning of the welding cycle n turns off before welding.

The device works as follows.

The blinking switch 12 is charged to the working capacitors 7 after connecting the block 11. The charge is made through the current limiting resistor 4: And the transistor 6. The thyristor 5 remains locked when it is locked to a small circuit with a target resistance ( ), which determines the low value of the constant charge time TI. The charge voltage increases in a stepwise curve (the time interval / i - tz of Fig. 2).

Thus, the inpouecc of the charge of the working battery. Capacitors occur at constant TI circuit time is sufficiently fast and: does not cause a decrease in the production of the welding machine.

When the capacitors 7 reach the specified value of the a-pr plen of the signal from the divider 8, the signal of the reference voltage on thyristors 5 and 6 is alarmed, and when the instantaneous value of the charging voltage becomes equal to the m / instantaneous value of the on-ier on the working capacitors 7 (moment / h), thyristor 6 is lost, the last impulse of charging is given (4–3). In the future, capacitors are only recharged in the process of automatically maintaining a predetermined voltage having a saw-tooth shape (Fig. 2).

Capacitors - after the time tz are discharged through the divider 8 during the time determined by the magnitude and time of the discharge circuit and the sensitivity of the block 11. When the instantaneous value of the charging voltage exceeds the instantaneous value of the capacitor 7 (after the moment U) and the control unit 11, when the voltage is reduced at divider 8, re-supplies the control voltage, the thyristor 6 rests, a new process begins - iodzar and working capacitors all with the same constant Time of the circuit. The charge current pulse (instant is) the breaker 12 opens (for example, at time t). The thyristor b is locked at time / e and, starting from the moment of IT, the battery is recharged through the charge thyristor 5 and the current-limiting source 3. Continuous The charging time T2 C-R2 increases dramatically, and the sawtooth shape voltage is also automatically maintained at the target level, however, the amplitude of the oscillations, starting from the time t, decreases significantly, since it is already determined by the value of C – L). As a result, the accuracy of C) increases abilizacin.

The process of charging the charge co-operation of the cotoidocoopii in connection with a large value of T2 is already more frequent and in the limit is one half-period of the charging voltage, i.e. 10 iM / ceK.

At the end of the next welding cycle, a battery of capacitors is discharged to the winding of the welding transformer: mator, after switching the discharge valve 9 (for example, at time ts), and disconnected beforehand

control unit I.

Subject invention

A device for capacitor welding of predominantly small parts, including a rectifier, a circuit of a series-connected current limiting resistor and a charge thyristor, working co-capacitors, a voltage divider connected in parallel to the capacitors, a discharge valve, a welding transformer and a control unit for stabilizing the charge, characterized by that, in order to increase the accuracy of voltage stabilization on the working capacitors, parallel to the circuit of the charge thyristor and the current-limiting resist An oracle is connected to a similar circuit, the resistor of which is several orders of magnitude greater than the resistance of the current-limiting resistor, and an interrupter is connected to the circuit of the charge-thyristor control electrode.

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