Electric controls with -transistors

Claim 1

IN AN ELECTRIC CONTROL SYSTEM, A SOURCE OF CURRENT; A LOAD CONNECTED TO RECEIVE CURRENT PATH THERETHROUGH IN A TRANSISTOR HAVING A MAIN CURRENT PATH THERETHROUGH IN SERIES WITH LOAD, AND SAID PATH BEING NORMALLY NON-CONDUCTING; AND THE TRANSISTOR HAVING AN ACTIVATING CURRENT PATH THEREIN WHICH WHEN ENERGIZED RENDERS THE MAIN PATH OF THE TRANSISTOR CONDUCTING; A FIRST CONTACTOR IN A CIRCUIT CONNECTED TO A CURRENT SOURCE AND TO THE ACTIVATING PATH AND ENERGIZING IT TO RENDER THE TRANSISTOR CONDUCTING WHEN THE CONTACTOR IS CLOSED, TO THEREBY CAUSE CURRENT TO FLOW IN THE LOAD; A MAINTAINING CIRCUIT ARRANGED TO DERIVE CURRENT FROM THE LOAD CURRENT AND CONNECTED TO THE ACTIVATING PATH OF THE TRANSISTOR TO MAINTAIN IT ACTIVATED; A SECOND CONTACTOR IN A SECOND CIRCUIT CONNECTED TO A CURRENT SOURCE AND TO THE ACTIVATING PATH AND NEUTRALIZING ACTIVATION OF THE TRANSISTOR TO RENDER THE TRANSISTOR NONCONDUCTING WHEN THE SECOND CONTACTOR IS CLOSED, AND THEREBY INTERRUPTING THE CURRENT IN THE LOAD AND IN THE MAINTAINING CIRCUIT.