Direct current static switch

Claim 1

A DIRECT CURRENT STATIC SWITCH FOR MAKING AND BREAKING A CONNECTION BETWEEN A VOLTAGE SOURCE AND A LOAD IMPEDANCE, SAID SWITCH COMPRISING A FIRST CONTROLLED RECTIFIER CONNECTED IN SERIES WITH SAID LOAD IMPEDANCE BETWEEN A FIRST AND A SECOND TERMINAL, A SECOND CONTROLLED RECTIFIER, A FIRST COMMUNTATING CAPACITOR AND A FIRST CHARGING RESISTOR; EACH OF SAID CONTROLLED RECTIFIERS HAVING ANODE, CATHODE AND GATE ELECTRODES; SAID CATHODES OF SAID FIRST AND SECOND CONTROLLED RECTIFIERS BEING CONNECTED TO SAID SECOND TERMINAL, SAID SECOND CONTROLLED RECTIFIER AND SAID FIRST COMMUTATING CAPACITOR BEING CONNECTED IN SERIES BETWEEN THE ANODE AND CATHODE OF SAID FIRST CONTROLLED RECTIFIER, SAID FIRST CHARGING RESISTOR BEING CONNECTED BETWEEN SAID FIRST TERMINAL AND THE JUNCTION POINT OF SAID FIRST COMMUTATING CAPACITOR AND SAID SECOND CONTROLLED RECTIFIER; WHEREIN THE IMPROVEMENT COMPRISES A CONTROL MEANS FOR AUTOMATICALLY BRINGING SAID SECOND CONTROLLED RECTIFIER TO THE OFF-STATE, SAID CONTROL MEANS INCLUDING A SECOND COMMUTATING CAPACITOR, A CONTROLLED SEMI-CONDUCTOR DEVICE HAVING ANODE, CATHODE AND GATE ELECTRODES, A SECOND CHARGING RESISTOR, AND A VOLTAGE SENSING MEANS; SAID SECOND COMMUTATING CAPACITOR AND SAID CONTROLLED SEMI-CONDUCTOR DEVICE BEING CONNECTED IN SERIES BETWEEN THE ANODE AND CATHODE OF SAID SECOND CONTROLLED RECTIFIER; SAID SECOND CHARGING RESISTOR BEING CONNECTED BETWEEN SAID FIRST TERMINAL AND THE JUNCTION POINT OF SAID SECOND COMMUTATING CAPACITOR AND SAID SEMI-CONDUCTOR DEVICE; AND VOLTAGE SENSING MEANS BEING CONNECTED BETWEEN THE ANODE AND GATE ELECTRODE OF SAID SEMI-CONDUCTOR DEVICE FOR APPLYING A GATING CURRENT TO THE GATE ELECTRODE OF SAME SEMICONDUCTOR DEVICE AT A PREDETERMINED VOLTAGE LEVLE.