Control circuit for electronic conduction-latching devices

Claim 1

A CONTROL CIRCUIT FOR AN ELECTRONIC CONDUCTION-LATCHING DEVICE OF THE TYPE HAVING A CONTROL CATHODE AND ANODE ELECTRODE AND IN WHICH CONDUCTION IN INITIATED BETWEEN THE CATHODE AND ANODE ELECTRODE FROM THE CONTROL ELECTRODE AFTER WHICH THE CONTROL ELECTRODE EXERTS NO FURTHER CONTROL OVER CONDUCTION OF THE DEVICE UNTIL IT HAS BEEN EXTINGUISHED AS BY A TEMPORARY REDUCTION OF THE ANODE POTENTIAL THEREOF; AN INPUT CIRCUIT FOR SAID DEVICE INCLUDING A SERIALLY CONNECTED PHOTOCELL HAVING AN ANODE AND CATHODE, A SOURCE OF INPUT OPERATING POTENTIAL HAVING ONE SIDE CONNECTED TO THE CATHODE OF THE PHOTOCELL, A RESISTOR HAVING ONE TERMINAL CONNECTED TO THE ANODE OF THE PHOTOCELL AND TO THE CONTROL ELECTRODE OF SAID DEVICE AND ITS OTHER TERMINAL CONNECTED TO THE OTHER SIDE OF SAID SOURCE OF INPUT OPERATING POTENTIAL, AND MEANS FOR ILLUMINATING SAID PHOTOCELL; AN OUTPUT CIRCUIT INCLUDLING A SOURCE OF OUTPUT OPERATING POTENTIAL AND A UTILIZATION DEVICE CONNECTED BETWEEN THE ANODE ELECTRODE OF SAID ELECTRONIC LATCHING DEVICE AND THE SOURCE OF OUTPUT OPERATING POTENTIAL, SAID UTILIZATION DEVICE BEING NORMALLY DEACTIVATED IN THE PRESENCE OF ILLUMINATION ON SAID PHOTOCELL AND ADAPTED TO BE ENERGIZED BY CURRENT FLOW FROM SAID SOURCE OF OPERATING POTENTIAL THROUGH SAID ELECTRONIC LATCHING DEVICE UPON THE REMOVAL OF ILLUMINATION ON SAID PHOTOCELL TO LATCH SAID DEVICE INTO CONDUCTION; AND MEANS FOR RE-ESTABLISHING CONTROL OF SAID UTILIZATION DEVICE FROM THE CONTROL ELECTRODE OF SAID ELECTRONIC LATCHING DEVICE COMPRISING A SECOND ELECTRONIC LATCHING DEVICE HAVING A CONTROL, CATHODE AND ANODE ELECTRODE, CAPACITOR COUPLING MEANS CONNECTED BETWEEN THE ANODE ELECTRODES OF THE FIRST DEVICE AND THE SECOND DEVICE AND BETWEEN THE ANODE ELECTRODE OF SAID FIRST DEVICE AND THE CONTROL ELECTRODE OF SAID SECOND DEVICE, A SECOND RESISTOR CONNECTED BETWEEN THE ANODE ELECTRODE OF THE FIRST DEVICE AND THE CONTROL ELECTRODE OF SAID SECOND DEVICE, A THIRD RESISTOR ELECTRICALLY CONNECTED TO THE CONTROL ELECTRODE OF SAID SECOND DEVICE AND FORMING A VOLTAGE DIVIDER WITH SAID SECOND RESISTOR, AND AN ANODE LOAD RESISTOR CONNECTED BETWEEN THE ANODE ELECTRODE OF SAID SECOND ELECTRONIC LATCHING DEVICE AND SAID SOURCE OF OUTPUT OPERATING POTENTIAL.