Means for measuring scale motions

Claim 1

APPARATUS FOR CONTINUOUSLY INDICATING THE ROTATION POSITION OF A SHAFT COMPRISING A FIRST TRANSDUCER ELEMENT MOUNTED ON THE SHAFT, A SECOND TRANSDUCER ELEMENT MOUNT FOR ROTATION ABOUT THE AXIS OF THE SHAFT ADJACENT TO THE FIRST ELEMENT, SAID ELEMENTS BEING OPERATIVELY ASSOCCIATED FOR THE CONTINUOUS PRODUCTION OF PULSES AT ALL TIMES DIRECTLY PRODUCTIONAL IN RATE OF OCCURRENCE TO THE RATE OF RELATIVE MOTION THEREBETWEEN, MEANS FOR ROTATING THE SECOND ELEMENT IN A CONSTANT DIRECTION AT A SPEED EXCEEDING THE MAXIMUM SPEED OF THE SHAFT UNDER MEASUREMENT, SECOND PLUSE-PRODUCING MEANS FOR PRODUCING PULSE AT ALL TIMES DIRECTLY PROPORTIONAL IN RATE OF OCCURRENCE ONLY TO THE SPEED OF ROTATION OF THE SECOND ELEMENT, THE FACTORS OF PROPORTIONALITY BEING EQUAL, AND MEANS FOR CONTINUOUSLY REGISTERING THE DIFFERENCE IN THE TOTAL NUMBERS OF PULSES PRODUCED BY SAID SECOND PULSE-PRODUCING MEANS AND SAID TRANSDUCER ELEMENTS, WHEREBY THE REGISTERING MEANS CONTINUOSULY INDICATES THE ROTATIONAL POSITION OF THE SHAFT UNDER MEASUREMENT.