Position indicating arrangement

Claim 1

AN INDICATING ARRANGEMENT COMPRISING AN ELEMENT OF MAGNETIC MATERIAL WHICH IS MOVABLE OVER A GIVEN PATH, OF PRIMARY AND ONE SECONDARY COIL DISTRIBUTED IN COUPLED RELATION ALONG THE LENGTH OF SAID PATH, MEANS FOR ENERGIZING SAID ONE PRIMARY COIL FROM AN ALTERNATING SOURCE, MAGNETIC COUPLING INFLUENCING MEANS POSITIONED ADJACENT ONLY ONE PORTION OF SAID PATH TO PRODUCE A SIGNAL FROM SAID SECONDARY COIL VARYING AS A FIRST FUNCTION OF THE POSITION OF SAID ELEMENT OVER SAID ONE PORTION OF SAID PATH AND VARYING AS A SECOND FUNCTION OF THE POSITION OF SAID ELEMENT OVER ANOTHER PORTION OF SAID PATH, REFERENCE CIRCUIT MEANS INCLUDING FIRST AND SECOND TRANSFORMERS HAVING THE PRIMARIES THEREOF CONNECTED FIR ENERGIZATION BY SAID SOURCE, SAID REFERENCE CIRCUIT MEANS INCLUDING A VARIABLE SHUNT RESISTOR SHUNTED ACROSS THE OUTPUT TERMINALS OF A SECONDARY OF SAID FIRST TRANSFORMER AND A VARIABLE RESISTOR CONNECTED IN SERIES WITH SAID FIRST TRANSFORMER SECONDARY, SAID SHUNT AND SERIES CONNECTED VARIABLE RESISTORS ALIGNING THE PHASE AND MAGNITUDE OF A VOLTAGE DERIVED FROM SAID FIRST TRANSFORMER SECONDARY WITH THAT OF SAID ONE SECONDARY COIL WHEN SAID MOVABLE ELEMENT IS LOCATED AT ONE LIMIT OF MOVEMENT, SAID REFERENCE CIRCUIT MEANS INCLUDING ANOTHER VARIABLE SHUNT RESISTOR SHUNTED ACROSS THE OUTPUT TERMINALS OF A SECONDARY OF SAID SECOND TRANSFORMER AND ANOTHER VARIABLE RESISTOR CONNECTED IN SERIES WITH SAID SECOND TRANSFORMER SECONDARY, A THIRD SHUNT RESISTOR CONNECTED TO SHUNT A PORTION OF SAID OTHER SERIES CONNECTED VARIABLE RESISTORS RESPECTIVELY SHUNT AND SERIES CONNECTED VARIABLE RESISTORS RESPECTIVELY ESTABLISHING THE PHASE AND MAGNITUDE OF A VOLTAGE DERIVED FROM SAID SECOND TRANSFORMER SECONDARY, MEANS FOR ADDING SAID LAST-MENTIONED VOLTAGE TO THE ALIGNED VOLTAGE DERIVED FROM SAID FIRST TRANSFORMER SECONDARY TO OBTAIN A TOTAL REFERENCE VOLTAGE CONFORMING SECONDARY TO OBTAIN SAID SECONDARY COIL, SAID THIRD SHUNT RESISTOR CAUSING THE MAGNITUDE OF THE VOLTAGE DERIVED FROM SAID SECOND TRANSFORMER SECONDARY TO VARY AS SAID FIRST AND SAID SECOND FUNCTIONS WITH MOVEMENT OF A POTENTIOMETER ARM RESPECTIVELY OVER SAID PORTION AND THE REMAINDER OF SAID OTHER SERIES CONNECTED VARIABLE RESISTOR, AND MEANS RESPONSIVE TO ANY DIFFERENCE BETWEEN SAID TOTAL REFERENCE VOLTAGE AND SAID ONE SECONDARY COIL SIGNAL TO CONFORM THE FORMER TO THE LATTER THROUGH MOVEMENT OF SAID POTENTIOMETER ARM, AND INDICATING MEANS RESPONSIVE TO SAID LAST-MENTIONED MEANS FOR INDICATING THE POSITION OF SAID MOVABLE ELEMENT.