Printing roller drive by electronically controlled stepping motor

摘要

The platen 3 of a selective printer is driven via gears 2 from a motor 1 which is controlled in response to measurement of the motion of paper supported thereon by a frictionally driven encoder 5, 6. A belt 4 is trained about a portion of the periphery of the roller 3 by a pair of further rollers on respective shafts 11a, 11b, one of which (11a) drives the encoder disc 5. Advantage: Less damaging to paper than prior art roller-driven encoders, which results in greater accuracy and unsoiled paper. <IMAGE>