Control-device for use in resistance welding systems

Claim 1

ELECTRICAL APPARATUS FOR USE IN A RESISTANCE WELDING SYSTEM, COMPRISING FIRST AND SECOND GASEOUS DISCHARGE TUBES ALTERNATELY ACTUATED TO PRODUCE RESPECTIVELY FIRST AND SECOND SIGNALS FOR INITIATING THE OPERATION OF SAID SYSTEM, INPUT MEANS FOR A FIRST CONTROL SIGNAL AT D.C. POTENTIAL HAVING A DURATION EQUAL TO THE DESIRED WELDING INTERVAL, INPUT MEANS FOR AN ALTERNATING CURRENT OF GIVEN FREQUENCY, MEANS FOR APPLYING THE ALTERNATING CURRENT TO SAID FIRST AND SECOND TUBES IN PHASE OPPOSITION THEREBY TO ALTERNATELY ENERGIZE THE SAME, A FIRST PULSE NETWORK AND A PHASE SHIFTER FOR PRODUCING SUBSEQUENT TO THE START OF SAID FIRST CONTROL SIGNAL FIRST PULSE SIGNALS RECURRING AT SAID GIVEN FREQUENCY DURING THE DURATION OF SAID FIRST CONTROL SIGNAL, A SECOND PULSE NETWORK AND A SECOND PHASE SHIFTER FOR PRODUCING SECOND PULSE SIGNALS RECURRING AT SAID GIVEN FREQUENCY AT AN INSTANT SUBSEQUENT TO THE OCCURRENCE OF SAID FIRST PULSE SIGNAL AND DURING THE DURATION OF THE FIRST CONTROL SIGNAL, AN ELECTRON TUBE CONNECTED TO SAID FIRST PULSE NETWORK FOR ATTENUATING THE INITIAL FIRST PULSE OCCURRING DURING A GIVEN WELDING INTERVAL, INPUT MEANS FOR A SECOND CONTROL SIGNAL AT D.C. POTENTIAL AND INITIATED AT THE START OF SAID FIRST CONTROL SIGNAL, MEANS FOR DELAYING THE SECOND CONTROL SIGNAL, MEANS FOR APPLYING THE DELAYED SECOND CONTROL SIGNAL TO SAID ELECTRON TUBE THEREBY TO ACTUATE THE SAME IN SYNCHRONISM WITH THE OCCURRENCE OF SAID FIRST CONTROL SIGNAL AND DURING THE INITIAL PORTION THEREOF, AND MEANS FOR APPLYING SAID FIRST CONTROL SIGNAL AND SAID RECURRING FIRST AND SECOND PULSES TO AT LEAST ONE OF SAID GASEOUS DISCHARGE TUBES THEREBY TO RECURRENTLY ACTUATE SAID WELDING SYSTEM IN SYNCHRONISM WITH THE OCCURRENCE OF THE INITIAL SAID SECOND PULSE SIGNAL AND SUBSEQUENTLY OCCURRING SAID FIRST PULSE SIGNALS APPLIED TO SAID ONE OF THE SAID GASEOUS DISCHARGE TUBES DURING THE OCCURRENCE OF SAID FIRST CONTROL SIGNAL.