Rotation position control servo circuit - has counter, differential counter and ratio multiplier controlled by processor circuit

摘要

Transparent strips in a shaft encoder disc (1) are scanned by two detectors (2,3). The detectors are positioned so that their outputs are 90 deg. out of phase. The outputs are fed via a first logic circuit (5), which determines the direction of rotation, to a second logic circuit which eliminates any pulses due to short reverse direction movements. The second circuit output (11) is fed to a counter (16) a differential counter (21) and a ratio multiplier (22) which are controlled by a processor circuit (18) and service panel (17). A label detector circuit (20,19) is also connected to the processor. The multiplier output is divided (23), amplified (24) and fed to a stopper motor (25) which drives two shafts (27,28) via a differential gear (26).