Digital position-indicating units adapted for use in apparatus for detecting and setting the position of a movable object, such as a rotatable shaft; and such apparatus

Claim 1

APPARATUS FOR DETECTING SAID SETTING THE POSITION OF A MOVABLE OBJECT, COMPRISING: A SIGNAL GENERATOR HAVING A SERIES OF OUTPUT CHANNELS AND ADAPTED TO PROVIDE SIMULTANEOUSLY A CORRESPONDING SERIES OF OUTPUT ELECTRICAL SIGNALS OF GENERALLY SIMILAR CHARACTER BUT DISTINGUISHED FROM ONE ANOTHER BY SERIALLY PROGRESSIVE DIFFERENCE OF ONE OF THREE CHARACTERISTICS THEREOF, NAMELY AMPLITUDE, FREQUENCY AND PHASE; A DIGITAL POSITION-INDICATING UNIT COMPRISING A PLURALITY OF SUCCESSIVELY LINKED SECTIONS, INCLUDING A FIRST AND AT LEAST SECTION, EACH OF WHICH SECTIONS COMPRISES A PLURALITY OF SEQUENTIALLY DISPOSED INPUT STATOR ELEMENTS, EACH ADAPTED TO HAVE APPLIED TO IT A RESPECTIVE INPUT ELECTRICAL SIGNAL, AND A REVERSIBLY MOVING PART WHICH, ON CONTINUED MOVEMENT WITHOUT REVERSAL, ASSUMES IN SEQUENCE EACH OF A PLURALITY OF SEQUENTIAL POSITIONS, EACH CORRESPONDING TO A RESPECTIVE ONE OF THE INPUT STATOR ELEMENTS, TO EACH OF WHICH SEQUENTIAL POSITIONS THE MOVING PART RETURNS PERIODICALLY ON SAID CONTINUED MOVEMENT, THE MOVING PART OF THE SAID FIRST OF THE SECTIONS BEING ADAPTED FOR MECHANICAL CONNECTION TO, AND THEREBY FOR MOVEMENT PROPORTIONAL TO MOVEMENT OF, THE MOVABLE OBJECT WHOSE POSITION TO BE INDICATED, AND THE MOVING PART OF EACH SUCCEEDING SECTION BEING SO CONNECTED TO THE RESPECTIVE PRECEDING SECTION THAT, ON MOVEMENT OF THE MOVING ARM OF THE SAID PRECEDING SECTION FROM ONE TO THE OTHER OF A SELECTED PAIR OF MUTUALLY ADJACENT SEQUENTIAL POSITIONS THEREOF, AND DEPENDENT ON THE DIRECTION OF MOVEMENT THEREOF, THE MOVING ARM OF THE SAID SUCCEEDING SECTION