Variable frequency to constant frequency converters

Claim 1

A FREQUENCY CHANGER FOR CHANGING A HIGH FREQUENCY ALTERNATING POLYPHASE INPUT CURRENT SUPPLIED FROM A GENERATOR AND FLOWING THROUGH A FIRST CIRCUIT INTO A LOW FREQUENCY ALTERNATING OUTPUT CURRENT FLOWING THROUGH A SECOND CIRCUIT, SAID FREQUENCY CHANGER COMPRISING: A PLURALITY OF PAIRS OF RECTIFIERS, THE TWO RECTIFIERS OF EACH PAIR, IN OPPOSITION WITH EACH OTHER, BEING DISPOSED BETWEEN ONE PHASE OF SAID FIRST CIRCUIT AND SAID SECOND CIRCUIT, SAID RECTIFIERS INCLUDING GATE CONTROL MEANS FOR MAKING THEM CONDUCTIVE FOR PERIODS THAT GO INCREASING DURING A FIRST POSITION OF EVERY ALTERNATION OF SAID CURRENT, THEN REMAIN AT A MAXIMUM VALUE DURING THE MIDDLE PORTION OF SAID ALTERNATION AND GO DECREASING DURING THE LAST PORTION OF SAID ALTERNATION, MEANS FOR PRODUCING A SUCCESSION AT SAID LOW FREQUENCY OF VOLTAGE SIGNALS EACH COMPRISING SUCCESSIVELY, FOR EVERY ALTERNATION, AN INCREASING VOLTAGE PORTION, A SUBSTANTIALLY CONSTANT VOLTAGE PORTION AND A DECREASING VOLTAGE PORTION, IN ABSOLUTE VALUE, MEANS OPERATIVE BY SAID GENERATOR FOR PRODUCING A SUCCESSION AT SAID HIGH FREQUENCY OF VOLTAGE SIGNALS CONSISTING OF SAW TEETH OF CONSTANT AMPLITUDE, A CHARGING NETWORK OF THE RESISTOR-CAPACITOR TYPE FED FROM SAID LAST MENTIONED MEANS WITH THE SUCCESSION OF HIGH FREQUENCY SIGNALS, AND IN EACH PHASE A SINGLE UNIJUNCTION TRANSISTOR HAVING INPUTS CONNECTED WITH THE OUTPUT OF SAID FIRST MENTIONED MEANS AND WITH THE OUTPUT OF SAID NETWORK FOR COMPARING THE SIGNALS FROM SAID OUTPUTS AND HAVING AN OUTPUT CONNECTED TO SAID GATE CONTROL MEANS CAPABLE, EVERY TIME THE CHARGE OF SAID NETWORK REACHES A VALUE WHICH IS IN GIVEN LINEAR RELATION TO THE VALUE OF THE LOW FREQUENCY SIGNAL AT THE SAME TIME, OF DISCHARGING SAID CHARGING NETWORK AND OF FEEDING A PULSE TO SAID GATE CONTROL MEANS.