Self-controlled inverter with a commutating oscillatory circuit

Claim 1

A SELF-CONTROLLED INVERTER FOR GENERATING FROM A SOURCE OF UNIDIRECTIONAL VOLTAGE AN ALTERNATING VOLTAGE HAVING A RECTANGULAR WAVE FORM WHICH IS NOT AFFECTED BY THE LOAD,, COMPRISING A PLURALITY OF INVERTER BRANCHES CONNECTED TO SAID SOURCE OF UNIDIRECTIONAL VOLTAGE, EACH SAID INVERTER BRANCH INCLUDING A CONTROLLABLE VALVE OPERATING AS THE MAIN VALVE AND AN UNCONTROLLABLE VALVE CONNECTED IN ANTI-PARALLEL THEREWITH, AND AN OSCILLATORY CIRCUIT FOR COMMUTATING SAID MAIN VALVE COMPRISING A CONDENSER AND AN INDUCTANCE IN SERIES WITH A CONTROLLABLE COMMUTATING VALVE AND A SECOND UNCONTROLLABLE VALVE CONNECTED IN ANTI-PARALLEL, EACH SAID MAIN VALVE AND ITS ASSOCIATED COMMUTATING VALVE TOGETHER WITH SAID OSCILLATORY CIRCUIT ESTABLISHING A NETWORK EXTENDING BETWEEN THE POLES OF SAID SOURCE OF UNIDIRECTIONAL VOLTAGE AND BEING CONTROLLED SUCH THAT SAID MAIN VALVE IN EACH SAID BRANCH IS FIRED AT THE BEGINNING OF THE RELATED HALF WAVE OF ALTERNATING VOLTAGE TO BE GENERATED AND THE ASSOCIATED COMMUTATING VALVE IS FIRED AT AN INSTANT WHICH PRECEDES THE END OF SAID HALF-WAVE OF ALTERNATING VOLTAGE BY A TIME INTERVAL AT LEAST EQUAL TO ONE QUARTER OF THE PERIOD OSCILLATION OF SAID OSCILLATORY CIRCUIT, AND A THIRD UNCONTROLLABLE VALVE CONNECTED TO SAID OSCILLATORY CIRCUIT WHICH CARRIES CURRENT AND EFFECTS RECHARGING OF SAID CONDENSER IN PREPARATION FOR THE FOLLOWING HALF-WAVE OF ALTERNATING VOLTAGE DURING THE TIME INTERVAL THE OTHER VALVES DO NOT CARRY CURRENT.