Control circuit for unidirectional current conducting devices

Claim 1

IN A CONTROL CIRCUIT FOR UNIDIRECTIONAL CURRENT CONDUCTING DEVICES, A PHASE SHIFTING NETWORK COMPRISING: A CAPACITIVE VOLTAGE DIVIDING MEANS INCLUDING AT LEAST A FIRST AND A SECOND CAPACITIVE ELEMENT SERIALLY CONNECTED TO ONE ANOTHER WITH A CENTER TAP THEREBETWEEN; SAID DIVIDING MEANS ADAPTED TO BE CONNECTED ACROSS AN ALTERNATING CURRENT SUPPLY FOR RECEIVING THEREFROM AN INPUT SIGNAL; THE SERIES COMBINATION OF A RESISTIVE ELEMENT AND A THIRD CAPACITIVE ELEMENT CONNECTED ACROSS SAID VOLTAGE DIVIDING MEANS; THE SERIES COMBINATION OF A FOURTH CAPACITIVE ELEMENT AND AN INDUCTIVE ELEMENT CONNECTED ACROSS SAID THIRD CAPACITIVE ELEMENT; MEANS VARYING THE RELATIVE IMPEDANCE OF SAID INDUCTIVE AND FOURTH CAPACTIVE ELEMENTS WHEREBY SAID NETWORK IS ADAPTED TO PRODUCE AN OUTPUT SIGNAL BETWEEN SAID TAP AND THE JUNCTION BETWEEN SAID FOURTH CAPACITIVE ELEMENT AND SAID INDUCTIVE ELEMENT, WHICH OUTPUT SIGNAL IS PHASE SHIFTED RELATIVE TO THE INPUT SIGNAL IN RESPONSE TO THE VALUE OF THE IMPEDANCE OF SAID INDUCTIVE ELEMENT WITH RESPECT TO SAID FOURTH CAPACITIVE ELEMENT; FURTHER PHASE RETARDING AND SIGNAL PEAKING MEANS WHICH INCLUDE ANOTHER INDUCTIVE ELEMENT; A TRANSFORMER HAVING A PRIMARY AND A SECONDARY WINDING CONNECTED TO RECEIVE SAID OUTPUT SIGNAL WHEREBY SAID OUTPUT SIGNAL FLOWS SERIALLY THROUGH SAID ANOTHER INDUCTIVE ELEMENT AND PRIMARY TRANSFORMER WINDING; SAID PRIMARY TRANSFORMER WINDING BEING POSSESSED OF AN IMPEDANCE WHICH PRESENTS A SUBSTANTIAL LOAD TO THE PHASE SHIFTING NETWORK TO CAUSE THE OUTPUT SIGNAL AFTER BEING MODIFIED BY SAID RETARDING AND PEAKING MEANS TO BE AT LEAST ONE SPIKE SHAPED PULSE FOR EACH HALF CYCLE OF SAID ALTERNATING CURRENT INPUT SIGNAL; A SET OF UNIDIRECTIONAL CURRENT CONDUCTING DEVICES CONNECTED TO SAID SECONDARY WINDING FOR RECEIVING SAID SPIKE SHAPED PULSE TO CAUSE SAID DEVICES TO PASS CYCLICALLY FROM THEIR NON-CONDUCTIVE STATE TO THEIR CONDUCTIVE STATE, AND SAID FIRST, THIRD AND FOURTH CAPACITIVE ELEMENTS BEING IN SERIES WITH SAID ANOTHER INDUCTIVE ELEMENT AND PRIMARY TRANSFORMER WINDING FORMING A LOW IMPEDANCE RETURN PATH FOR SAID PULSE SIGNAL.