A.c. switch

Claim 1

IN COMBINATION WITH AN A.C. POWER SUPPLY, A LOAD AND A UNDIRECTIONAL POTENTIAL SOURCE WHICH PRODUCES A FIRST SIGNAL IN RESPONSE TO A FIRST GIVEN CONDITION AND A SECOND SIGNAL IN RESPONSE TO A SECOND GIVEN CONDITION, A BRIDGE RECTIFIER HAVING A PAIR OF A.C. INPUT TERMINALS IN SERIES ARRANGEMENT WITH THE POWER SUPPLY AND THE LOAD AND POSITIVE AND NEGATIVE D.C. OUTPUT TERMINALS, THE COMBINATION OF A TRANSFORMER IN CIRCUIT WITH SAID POWER SUPPLY, SAID RECTIFIER AND SAID LOAD AND RECTIFYING MEANS IN CIRCUIT WITH THE OUTPUT OF SAID TRANSFORMER FOR DERIVING A PULSE TRAIN COMPRISING PULSES IN SYNCHRONISM WITH THE HALF CYCLES OF OUTPUT FROM SAID POWER SUPPLY, A GATE CONTROLLED RECTIFIER HAVING AN ANODE CONNECTED TO SAID POSITIVE TERMINAL, A CATHODE CONNECTED TO SAID NEGATIVE TERMINAL AND A GATE ELECTRODE, ACTIVE MEANS WHICH IS ONLY RENDERED CONDUCTIVE UPON THE APPLICATION THERETO OF A PULSE COINCIDENT WITH THE OCCURRENCE OF ONE OF SAID SIGNALS, AND MEANS IN CIRCUIT WITH SAID UNDIRECTIONAL POTENTIAL SOURCE FOR APPLYING THE OUTPUT OF SAID ACTIVE MEANS TO SAID GATE ELECTRODE.