Xerox Phaser 8560MFP Service Documentation page 291

NOTE: The drum rotates CW for Transfix, CCW for Maintenance and Printing.
Figure 17 Drum Assembly Components
Always keep your fingers away from the drum drive system; it uses a closed-loop servo
drive system. Since the motor speeds up if it senses the drum drive system slowing
down, fingers caught in the drum belts and gears can be severely injured.
Transfix System
The transfix roller applies pressure to the back side of the paper as it moves between the trans-
fix roller and drum. This pressure transfers the image from the drum to the paper. A set of
springs determines how much pressure the transfix roller applies in the load module against
the drum. The pressure must be uniform across the length of the transfix roller to avoid paper
wrinkles and light spots on the prints.
After the transfix roller is engaged, the drum rotates to advance the paper during the transfix
process. The drum continues to advance the paper until the transfix roller is disengaged. The
transfix roller is lifted and lowered by the action of the process drive. All gears move to rotate
the transfix camshaft to bring the transfix roller into contact with the drum. The gears reverse to
rotate the transfix roller back to its original position, except when printing from Tray 1 or on
envelopes. The transfix load springs and double lever arms increase the force when the cam-
shaft is engaged.
Initial Issue
Phaser 8510/8560MFP Multifunction Product
WARNING
Never attempt to adjust or increase the transfix pressure on the springs.
Drum Maintenance System
The drum maintenance system creates a thin, intermediate, liquid transfer surface, a layer of
silicone oil, on the surface of the drum prior to printing. The oil keeps the ink from sticking to the
drum's surface and facilitates its transfer to the sheet of paper or transparency film. The oil is
contained in a porous foam roller.
Prior to each print, the process motor drives a cam to raise the pivot plate, which raises the oil
roller against the rotating drum. The same cam raises the compliant wiper blade to assure that
the oil film is smooth and even across the drum's surface. The process drive rotates in one
direction. This rotates the drum maintenance camshaft and raises the drum maintenance sys-
tem to the drum. The process drive then rotates in the opposite direction to lower the drum
maintenance system. The blade removes oil and drains it back into the maintenance kit drawer
through a felt filter. The oil roller can then reuse the oil. As the drum completes one rotation, the
rotating cam lowers the oil roller and then lowers the blade.
The drum has a floating deadband, the narrow section of the drum containing excess oil and
other debris. The oil bar is left on the drum surface when the blade is removed from the drum.
This oil bar location is controlled to keep it outside of the print area.
An EEPROM chip, built-in to the maintenance kit, stores the number of oiling cycles performed
by the drum maintenance system. The EEPROM stores the number of prints remaining to track
consumable life. At system startup, four oiling cycles are performed to condition the drum
10/2006
8-19
CAUTION
Figure 18 Transfix System
Theory of Operation
Image Output Terminal