Xerox Phaser 8860, Service Manual

Page: 304 / 316

09/2007
8-12 Phaser 8860/8860MFP Service Manual
Image Output Terminal
Initial Issue Theory of Operation
System Drive
Figure 6 System Drive Component Locations
Process Drive
The Process Drive is an open loop system that transmits torque to two camshaft assemblies.
One camshaft assembly, Transfix Camshaft, controls Transfix Roller loading. The second cam-
shaft, Drum Maintenance Camshaft, controls the Drum Maintenance and Printhead tilt sys-
tems. A DC servo motor powers the Process Drive to rotate the gears to specific positions
during the printing process. The Process Drive is able to actuate each camshaft system inde-
pendently or concurrently through the use of the swing gear in the gear train. Operation of the
transfix and drum maintenance system is controlled by the rotational direction of the motor.
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 subsystems to
self home during operation. If either the gearbox or cam gears is out of home during installa-
tion, the system does not function properly.
Figure 7 Process Drive Assembly