摘要 |
FIELD: welding processes and equipment, namely apparatuses for welding by means of modulated current, possibly during welding processes with automatic or semi-automatic control of parameters. ^ SUBSTANCE: apparatus includes electric current modulator that is connected in circuit for controlling welding current between DC source and automatic control system. Modulator includes switching unit, control circuit and divider. Switching unit includes one outlet being also outlet of modulator and three inputs. First input is control input; it is connected with outlet of circuit for controlling switching unit. Second inlet of switching unit is connected with automatic control system; third inlet of switching unit is connected with divider. Circuit for controlling switching unit may include connected in series: transformer whose inlet is connected to mains, bridge type rectifier, Schmitt trigger, counter and single shot multi-vibrator whose outlet is connected to control inlet of switching unit. Divider may have two resistors mutually connected in series. Inlet of divider is connected with outlet of automatic control system. Common point of resistors is connected with inlet of switching unit. ^ EFFECT: high quality welding due to simplified reliable circuit for generating modulated welding current. ^ 3 cl, 6 dwg |