Proportional control two-phase servomotor amplifier

Claim 1

A CONTROL CIRCUIT FOR AN ELECTRIC SERVO MOTOR, COMPRISING CONTROLLED RECTIFIER MEANS HAVING A GATING TERMINAL, SAID CONTROLLED RECTIFIER MEANS HAVING AN ANODECATHODE CIRCUIT OPERATIVELY CONNECTED TO SAID MOTOR AND TO A REFERENCE VOLTAGE, SAID CONTROLLED RECTIFIERS CONTROLLING THE SPEED OF SAID MOTOR AS A DIRECT FUNCTION OF THE TIME IN THE CYCLE OF CONTROLLED RECTIFIER-ANODE SUPPLY VOLTAGE THAT SAID CONTROLLED RECTIFIER MEANS RECEIVES A GATING PULSE; MEANS GENERATING A SQUARE WAVE PEDESTAL VOLTAGE THE AMPLITUDE OF WHICH VARIES AS A DIRECT FUNCTION OF AN ERROR SIGNAL, MEANS GENERATING A RIDER VOLTAGE OF INCREASING MONOTONIC WAVE FORM SYNCHRONIZED WITH RESPECT TO A SINUSOIDAL REFERENCE VOLTAGE, MIXING MEANS OPERABLE TO SUPERIMPOSE SAID RIDER VOLTAGE ON SAID PEDESTAL VOLTAGE THEREBY PRODUCING A MIXED OUTPUT VOLTAGE, PULSE GENERATING MEANS CONNECTED TO SAID MIXING MEANS AND THE GATING TERMINALS OF SAID CONTROLLED RECTIFIER MEANS OPERABLE TO APPLY SAID MIXED VOLTAGE TO THE GATING TERMINAL OF SAID CONTROLLED RECTIFIERS AT A TIME IN THE CYCLE OF ANODE SUPPLY VOLTAGE WHICH VARIES AS A DIRECT FUNCTION OF THE AMPLITUDE OF SAID PEDESTAL VOLTAGE.