Transistor circuits for switching high currents through an inductive load

Claim 1

A TRANSISTOR CIRCUIT FOR SWITCHING HIGH CURRENTS THROUGH AN INDUCTIVE LOAD, COMPRISING: TWO SEMI-CONDUCTIVE DEVICES, EACH HAVING A CONTROL ELKECTRODE, TWO MAIN ELECTRODES AND A MAIN CURRENT PATH, A TRANSFORMER HAVING A PRIMARY AND A SECONDARY WINDING, ONE END OF SAID PRIMARY AND SECONDARY WINDINGS BEING CONNECTED TOGETHER ANJD COUPLED TO ONE END OF AN INDUCTIVE LOAD, THE OTHER END OF THE INDUCTIVE LOAD BEING COUPLED TO CORRESPONDING MAIN ELECTRODES OF THE DEVICES BEING CONNECTED TO THE MAIN ELECTRODES OF THE DEVICES BEING CONNECTED TO THE OTHER ENDS OF SAID PRIMARY AND SECONDARY WINDINGS RESPECTIVELY, MEANS FOR APPLYING A PULSE TRAIN SIMULTANEOUSLY TO BOTH CONTROL ELECTRODES, SAID PULSE TRAIN RENDERING BOTH OF SAID DEVICES SIMULTANEOUSLY CONDUCTIVE FOR A RELATIVELY LONG PERIOD OF TIME AND SIMULTANEOUSLY BLOCKING SAID DEVICES FOR A RELATIVELY SHORT PERIOD OF TIME, THE WINDING SENSE OF THE TRANSFORMER WINDINGS BEING SUCH THAT THE VOLTAGE AT THE OTHER CORRESPONDING MAIN ELECTRODE OF ONE DEVICE DECREASES WHEN THE VOLTAGE AT THE OTHER CORRESPONDING MAIN ELECTRODE OF THE OTHER DEVICE INCREASES, WHEREBY THE MAIN CURRENT PATHS OF THE BOTH DEVICES ARE IN SERIES WITH THE TRANSFORMER AND THE LOAD FOR EQUALIZING DIFFERENCES IN CURRENTS FLOWING THROUGH THE TRANSISTORS.