SU442902A1 - Device for automatic control of the welding circuit during arc welding with direct and alternating current - Google Patents

Description

one

A device for automatic control of a welding circuit in arc welding with direct and alternating current is known, comprising a welding arc power source, an electrode, a ballast resistor, a power contactor, an intermediate relay, a locking diode, and a resistor voltage divider.

The proposed device differs from the known one in that a charge-discharge unit made in the form of a capacitance and alternately connected to an electrode by its own terminals of a resistor and source is connected in parallel to one of the shoulders of a divider connected to each other through a contactor blocking contact. which other leads are permanently connected to the product.

This solution allows you to completely remove the voltage from the electrode at the end of welding and restore it before starting welding directly from the workplace.

The proposed device contains a source of welding current 1, a ballast rheostat 2, a rectifier 3, a coil of a power contactor 4, a power contact of a contactor 5, a block contact 6, 7, 8 of a power contactor, an intermediate relay coil 9, a contact 10 of an intermediate relay, blocking diodes 11, 15 capacitor 12, resistors 13, 14 voltage divider, electrode 16, DC source 17 with a voltage of 12 V and less, resistor 18 to discharge the capacitor.

Before starting welding between the electrode and the product, the source 17 is switched on temporarily, the current passing through the diode 15 charges the capacitor 12.

When the electrode 16 is closed on the product 19, the capacitor 12, discharging through the coil of the intermediate relay 9, turns on a lower,

which, by contact 10, supplies the voltage through the rectifier 3 to the coil of the power contactor 4, which, including its power contact 5, switches on the welding circuit; Auxiliary contact 8 includes a voltage divider. From the current flowing through the resistors 13, 14, most of the voltage falls on the resistor 13, and less on the resistor 14. The voltage drop across the resistor 14 is applied to the capacitor 12 and recharges it.

The capacitor charge voltage is selected to be no more than 12 volts. An electrodynamic flashlight with a series-connected diode, an alkaline battery, dry batteries, or other sources can serve as a DC source for a charge-discharge unit. Diode 11 is for

protection of electrolytic capacitor 12

locking the negative half-wave when welding with alternating current and erroneous connection of the source of welding current when welding with current and auxiliary current, as well as to exclude the discharge of the capacitor 12 to the resistor 14.

If it is necessary to perform welding Iia with a different current, another field is used. I and I diodes 15 and 15, the capacitor 12 and the source of the current 17 are switched accordingly. The diode 15 serves to shunt the coil of the relay 9 to charge the capacitor 12 from the source 17.

When the welding arc is energized, the supply voltage of the coil of contactor 4 decreases by the amount of voltage drop across the arc.

When the welding arc of the Hirranne coil of the power contactor 4 is broken, it automatically stops and the no-load voltage of the source 1 is removed by contact 5 from the electrode 16.

Between the electrode 16 and the product 19 remains the accumulation of charge of the capacitor 12.

For a complete removal of the electrode from the electrode between the electrode and the product,

RS. Is. .Gely 9 is not used up because the leakage current of the discharge current is much lower than the relay operation current.

Subject invention

The device for automatic curation of cuajjomroii with a stub when arc welding is constant. M II is variable. TOKO.VI, with () held, its power source of the welding arc, electrode, ballast resistor, power contactor, intermediate relay, latching diode and resistor voltage divider, distinguish pess with the fact that. to remove voltage from the electrode, and when welding is completed and restored before welding starts directly from the workplace, a charge-discharge unit is connected parallel to one of the divider arms connected to each other through a contactor contact block, made in the form of capacitance and anoerium, connected to the electrode by some of its own resistor and source terminals and a different voltage, which by other leads are permanently connected to the product.