Motor speed controller

Claim 1

A DIRECT CURRENT MOTOR SPEED CONTROLLER COMPRISING A DIRECT CURRENT MOTOR, A DIRECT CURRENT POWER SOURCE, A POWER SWITCH CONNECTED BETWEEN SAID POWER SOURCE AND SAID MOTOR TO PERIODICALLY APPLY SAID POWER TO SAID MOTOR RESPONSIVE TO ENERGIZING CONTROL SIGNALS, A SPEED CONTROL POTENTIOMETER, AN ELECTRICAL NETWORK INCLUDING THE ARMATURE COIL OF SAID MOTOR COUPLING THE VOLTAGE APPEARING ACROSS SAID ARMATURE COIL TO SAID SPEED CONTROL POTENTIOMETER, A BISTABLE MULTIVIBRATOR, AN INPUT CIRCUIT FOR SAID MULTIVIBRATOR COMPRISING THE WIPER ARM OF THE SPEED CONTROL POTENTIOMETER, A MODULATION FREQUENCY SOURCE, A DIODE GATE AND A SIGNAL COUPLING NETWORK, SAID CIRCUIT PROVIDING VARIABLE PULSE DURATION INPUT PULSES TO SAID MULTIVIBRATOR TO PRODUCE VARIABLE DURATION OUTPUT SIGNALS CORRESPONDING TO THE VOLTAGE ACROSS SAID ARMATURE COIL, DRIVER MEANS RESPONSIVE TO THE OUTPUT SIGNALS OF SAID MULTIVIBRATOR TO PROVIDE THE ENERGIZING CONTROL SIGNALS TO SAID POWER SWITHC, AND AN ARMATURE CURRENT REGENERATIVE FEEDBACK CIRCUIT COUPLED TO SAID MULTIVIBRATOR WHICH TENDS TO MAINTAIN SAID POWER SWITCH ENERGIZED.