Step motor controller

Claim 1

A CONTROLLING CIRCUIT FOR A STEPPER MOTOR HAVING A PLURALITY OF WINDINGS FOR CAUSING THE STEPPER MOTOR TO OPERATE IN DISCRETE STEPS IN RESPONSE TO APPLIED VOLTAGE PULSES IN ONE DIRECTION OR THE OTHER, COMPRISING IN COMBINATION, CIRCUIT MEANS INCLUDING A SOURCE OF VOLTAGE AND AN INPUT SOURCE OF DISCRETE PULSES, SAID CIRCUIT MEANS COMPRISING CONNECTED STAGES, THERE BEING A STAGE CORRESPONDING TO EACH OF A PLURALTITY OF WINDINGS OF THE STEPPER MOTOR, EACH OF SAID STAGES COMPRISING SWITCHING MEANS CONNECTED TO ENERGIZE ITS RESPECTIVE MOTOR WINDING IN RESPONSE TO AN INCOMING CONTROLLING PULSE, SAID SWITCHING MEANS OF EACH STAGE BEING COUPLED TO THE SWITCHING MEANS OF ADJACENT STAGES WHEREBY WHEN THE SWITCHING MEANS OF ANY STAGE IS CAUSED TO OPERATE SAID SWITCHING MEANS EXERTS AN INFLUENCE ON THE SWITCHING MEANS OF AN ADJACENT STAGE SO THAT THE NEXT INCOMING PULSE CAUSES OPERATION OF THE SWITCHING MEANS OF AN ADJACENT STAGE IN A DIRECTION, I.E., CLOCKWISE OR COUNTER-CLOCKWISE, DEPENDING UPON THE INPUT SOURCE OF INCOMING PULSES, THE SWITCHING MEANS OF EACH STAGE INCLUDING A SILICON SWITCHING DEVICE HAVING A PLURALITY OF ELECTRODES, INCLUDING A GATE ANODE AND A GATE CATHODE, THE THRESHOLD AT WHICH THE SWITCHING DEVICE CONDUCTS IN RESPONSE TO THE GATE CATHODE BEING DEPENDENT UPON THE VOLTAGE ON THE GATE ANODE WHEREBY WHEN THE SAID SWITCHING DEVICE OF ONE STAGE IS CONDUCTED A VOLTAGE IS IMPRESSED ON THE GATE ANODE OF THE SWITCHING DEVICE OF AN ADJACENT STAGE PREPARING THAT SWITCHING DEVICE TO BE CONDUCTED IN RESPONSE TO THE NEXT SUBSEQUENT INCOMING CONTROL PULSE.