Dimmer control circuit for fluorescent lamp using a controlled rectifier bridge circuit

Claim 1

CONTROL APPARATUS FOR APPLYING VARIABLE OPERATING POTENTIALS TO A FLUORESCENT LAMP WHICH COMPRISES FIRST AND SECOND LEAD MEANS FOR SUPPLYING ENERGIZING POWER TO A WINDING OF AN AUTO TRANSFORMER ADAPTED AND CONNECTED FOR SUPPLYING SAID OPERATING POTENTIALS TO SAID LAMP, FIRST AND SECOND SATURABLE REACTANCE TRANSFORMER CORE MEMBERS EACH HAVING A SECONDARY WINDING CONNECTED IN SERIES CIRCUIT WITH SAID LAMP AND SAID AUTOTRANSFORMER WINDING, FIRST AND SECOND PRIMARY WINDINGS FOR SAID FIRST AND SECOND TRANSFORMER CORE MEMBERS, RESPECTIVELY, SAID LAST NAMED WINDINGS BEING CONNECTED IN OPPOSED MAGNETIZING RELATION AND IN SERIES CIRCUIT WITH A CONTROL CIRCUIT HAVING FIRST AND SECOND OUTPUT TERMINALS, SAID CONTROL CIRCUIT COMPRISING, FIRST AND SECOND OPPOSITELY-POLED RECTIFYING ELEMENTS CONNECTED ACROSS SAID POWER SUPPLYING LEAD MEANS AND BEING RESPECTIVELY POLED FOR CURRENT CONDUCTION IN A LOW RESISTANCE DIRECTION FROM A CONNECTED ONE OF SAID LEAD MEANS TO SAID FIRST OUTPUT TERMINAL, FIRST AND SECOND, THREE-TERMINAL CONTROLLABLE RECTIFIER ELEMENTS EACH HAVING FIRST AND SECOND CONDUCTION TERMINALS CONNECTED IN SERIES CONDUCTION CIRCUIT WITH SAID RECTIFIER ELEMENTS, RESPECTIVELY, SAID THREE-TERMINAL RECTIFIER ELEMENTS HAVING ONE CURRENT CONDUCTION TERMINAL CONNECTED IN COMMON TO A SECOND CONTROL CIRCUIT OUTPUT TERMINAL ADAPTED FOR CONNECTION IN SERIES CIRCUIT WITH SAID VARIABLE REACTANCE PRIMARY WINDINGS, FIRST AND SECOND VARIABLE RESISTORS, FIRST AND SECOND CAPACITORS CONNECTED ACROSS SAID FIRST AND SECOND MEANS BY WAY OF RESPECTIVELY ASSOCIATED ONES OF SAID VARIABLE RESISTORS IN REVERSE ORIENTATION, MEANS FOR CONNECTING A COMMON TERMINAL OF SAID FIRST CAPACITOR AND SAID FIRST RESISTOR IN CONTROLLING RELATION TO A CONTROL TERMINAL OF SAID FIRST CONTROLLABLE RECTIFYING ELEMENT, SECOND MEANS FOR CONNECTING A COMMON TERMINAL OF SAID SECOND CAPACITOR AND SAID SECOND VARIBALE RESISTOR IN CONTROLLING RELATION WITH A CONTROL TERMINAL OF SAID SECOND CONTROLLABLE RECTIFIER ELEMENT, AND MEANS FOR VARYING THE RESISTANCE OF SAID VARIABLE RESISTORS, WHEREBY ILLUMINATION POTENTIALS APPLIED TO SAID FLUOROESCENT LIGHTING ELEMENT FROM SAID FIRST TRANSFORMER SECONDARY WINDING ARE VARIABLE FOR DIMMING OR BRIGHTENING SAID FLUORESCENT LIGHTING ELEMENT UPON VARIATION OF SAID VARIABLE RESISTORS.