Xerox 8500DN Service Manual - Page 36

Theory of Operation Process Drive A small DC servomotor powers the Process Drive gearbox to rotate the gears to specific positions during the printing process. The Process Drive is able to actuate each camshaft system independently through the use of the swing arm in the gear train. The rotational direction of the motor controls the operation of the transfix and drum maintenance system. When the process motor rotates in one direction, the swing gear engages the lower gears. When the motor rotates in the opposite direction, the upper gears are engaged. Since the system is open loop, special attention to the home position of the process drive gears and the mating camshaft gears is critical. The Process Drive gearbox is mechanically keyed upon installation via gear orientations. These gear orientations allow the printer subsystems to self-home during operation. If either the gearbox or cam gears is out of home during installation, the printer does not function properly. Process Drive Swing Gear Imaging Transfix Transfix Camshaft Process Motor Gear Process Motor Gear Drum Maintenance Camshaft Drum Maintenance s8500-009 2-4 Phaser 8400/8500/8550/8560 Color Printer Service Manual