Electric motor control system

Claim 1

A MOTOR CONTROL SYSTEM COMPRISING, A SOURCE OF DIRECT CURRENT, A FIRST WINDING FOR SAID MOTOR, A SECOND FIELD WINDING FOR SAID MOTOR, A PLURALITY OF PARALLEL CONNECTED POWER CONTROL TRANSISTORS CONNECTED IN SERIES WITH SAID FIRST FIELD WINDING AND IN SERIES WITH THE ARMATURE OF SAID MOTOR, A SWITCHING MEANS FOR CONNECTING SAID SECOND FIELD WINDING IN SERIES WITH SAID MOTOR ARMATURE AND ACROSS SAID SOURCE OF DIRECT CURRENT, A MULTIVIBRATOR CIRCUIT HAVING A SUBSTANTIALLY SQUARE WAVE OUTPUT OF VARIABLE WIDTH, A VARIABLE RESISTOR FOR CONTROLLING THE WIDTH OF THE OUTPUT PULSES OF SAID MULTIVIBRATOR, MEANS CONNECTING SAID MULTIVIBRATOR CIRCUIT WITH SAID POWER CONTROL TRANSISTORS WHEREBY THE CONDUCTION OF SAID POWER CONTROL TRANSISTORS, IS CONTROLED BY SAID SQUARE WAVE OUTPUT OF SAID MULTIVIBRATOR CIRCUIT A MANUALLY OPERABLE CONTROL MEANS, AND MEANS COUPLING SAID MANUALLY OPERABLE CONTROL MEANS WITH SAID VARIABLE RESISTOR AND WITH SAID SWITCHING MEANS, SAID MANUALLY OPRABLE CONTROL MEANS BEING OPERABLE IN ONE POSITION TO CLOSE SAID SWITCHING MEANS WHEREBY SAID SECND FIELD WINDING IS CONNECTED IN SERIES WITH THE ARMATURE OF SAID MOTOR AND DIRECTLY ACROSS THE SAID SOURCE OF DIRECT CURRENT.