Linear positioning servosystems

Claim 1

IN A LINEAR POSITIONING SYSTEM, IN COMBINATION, A COMMAND VOLTAGE DIVIDER INCLUDING A SIX-SIDED BRIDGE NETWORK EACH SIDE COMPRISED OF A PLURALITY OF POTENTIOMETER AND RESISTOR ELEMENTS, INPUT CIRCUIT MEANS CONNECTED TO THE SIX CORNERS OF SAID BRIDGE NETWORK, A SIX PHASE SOURCE OF POWER EACH PHASE RESPECTIVELY BEING CONNECTED TO SAID INPUT CIRCUIT MEANS TO ENERGIZE SAID NETWORK AT THE CORNERS WITH AN ALTERNATING SIGNAL SUPPLY SPACED IN PHASE FROM A REFERENCE BY APPROXIMATELY 60 ELECTRICAL DEGREES, POTENTIOMETER CIRCUIT MEANS CONNECTING DIAMETRICALLY OPPOSITE CORNER POINTS OF SAID BRIDGE NETWORK AND INCLUDING ADDITIONAL CIRCUIT MEANS CONNECTING SAID POTENTIOMETER WIPERS OF SAID CIRCUITS IN A COMMON CONNECTION TO FORM A NEUTRAL CONDUCTOR, A PLURALITY OF GANGED SWITCHES CONNECTED IN PART TO EQUALLY SPACED POTENTIOMETER WIPERS OF SAID POTENTIOMETERS IN SAID LEGS OF SAID BRIDGE NETWORK OVER ONE-HALF OF SAID NETWORK TO PROVIDE PHASE SIGNAL OUTPUTS DISPLACED IN PHASE 18 DEGREES, SAID SWITCHES BEING ADJUSTED TO PROVIDE PHASE SIGNAL OUTPUTS ACCORDING TO SWITCHING POSITIONS OF SAID SWITCHES TO PROVIDE A COARSE SIGNAL COMMAND VARIABLE IN PHASE FROM 0 TO 180 DEGREES BETWEEN ONE OF SAID SWITCHES AND SAID NEUTRAL CONDUCTOR, ADDITIONAL SWITCH MEANS INCLUDING THE PLURALITY OF GANGED SWITCHES CONNECTED RESPECTIVELY TO EQUALLY SPACED POTENTIOMETER WIPERS OF ALL SIX SIDES OF SAID BRIDGE NETWORK SAID SWITCHES PROVIDING A SIGNAL OUTPUT VARIABLE IN PHASE FROM 0 TO 360 DEGREES IN ACCORDANCE WITH VARYING SWITCH SETTINGS TO PROVIDE A FINE SIGNAL COMMAND, AMPLIFIER MOTOR MEANS ADAPTED TO BE ENERGIZED FROM SAID COMMAND VOLTAGE DIVIDER, CIRCUIT MEANS INCLUDING A RELAY MEANS ADAPTED TO CONNECT EITHER COARSE OR FINE SIGNAL COMMANDS TO SAID AMPLIFIER MEANS, A DRIVE SCREW DRIVEN BY SAID MOTOR AND MOUNTING A SLIDE ADAPTED TO BE LINEARLY POSITIONED IN ACCORDANCE WITH THE VARIABLE PHASE COMMAND VOLTAGE SIGNAL OUTPUTS OF COARSE AND FINE COMMANDS, FEEDBACK SYNCHROS INCLUDING A FINE AND A COARSE SYNCHRO GEARED TO SAID MOTOR AND SAID SLIDE TO PRODUCE VARIABLE PHASE FEEDBACK SIGNALS IN ACCORDANCE WITH ROTATION OF SAID MOTOR, CIRCUIT MEANS INCLUDING A SWITCHING MEANS SELECTIVELY CONNECTING ONE OR THE OTHER OF SAID FINE OR COARSE SYNCHROS TO SAID AMPLIFIER MEANS, PHASE DETECTION MEANS INCLUDED IN THE CIRCUIT BETWEEN SAID COMMAND VOLTAGE DIVIDER AND ROTOR WINDING OF SYNCHROS AND OPERATIVE TO PROVIDE A NULL OUTPUT TO SAID AMPLIFIER WHEN SAID PHASE SIGNALS FROM SAID COMMAND VOLTAGE SOURCE AND SAID SYNCHROS ARE 90 DEGREES DISPLACED IN PHASE, AND FURTHER CONTROL CIRCUIT MEANS FOR INITIATING THE OPERATION OF SAID MOTOR AND FOR OPERATING SAID RELAY AND SWITCHING MEANS TO SELECT SAID FINE OR COARSE COMMAND SIGNALS AND THE SYNCHRO SIGNALS TO BE FED TO SAID AMPLIFIER.