Pitch changing apparatus for proportional escapement typewriter

Claim 1

PITCH CHANGING APPARATUS FOR CHANGING THE PRINTING PITCH OF A TYPEWRITER HAVING ESCAPEMENT CONTROL APPARATUS AND A MOVABLE CARRIER COMPRISING: A PLURALITY OF SELECTIVELY ENGAGEABLE DRIVE MEANS FOR DRIVINGLY INTERCONNECTING SAID ESCAPEMENT CONTROL APPARATUS AND SAID MOVABLE CARRIER; EACH OF SAID DRIVE MEANS CORRESPONDING TO A PRINTING PITCH; A SCALE MEANS COMPRISING AN ELONGATED SCALE MEMBER HAVING A PLURALITY OF REFERENCE SCALES FORMED ON AND EXTENDING AXIALLY OF SAID MEMBER AT SPACED POINTS ABOUT THE PERIPHERY THEREOF; A POINTER MOUNTED FROM AND MOVABLE WITH SAID CARRIER DISPOSED IN COOPERATING RELATION WITH SAID SCALE MEMBER; AN INDICATOR HAVING LONGITUDINALLY SPACED PAIRS OF REFERENCE MARKS THEREON DEFINING AREAS OF VARIOUS LENGTHS DISPOSED ABOUT THE PERIPHERY OF SAID INDICATORS; MEANS MOUNTING SAID INDICATOR FOR INDEPENDENT LONGITUDINAL MOVEMENT WITH RESPECT TO AND ROTARY MOVEMENT WITH SAID SCALE MEMBER;