Xerox Phaser 8860, Service Manual

Page: 305 / 316

09/2007
8-13 Phaser 8860/8860MFP Service Manual
Image Output Terminal
Theory of Operation Initial Issue
Media Drive Assembly
The Media Drive assembly controls each roller in the paper transport system. A gear train
located behind the motor connects it to the exit rollers, which are built into the Exit Module.
Gear trains located within the Media Drive Assembly, along with two clutches and a solenoid,
allow the motor to control the Pick, Take Away, Duplex, and deskew rollers. A unique swing
gear allows the Pick and Take Away roller to rotate in the same direction regardless of the
direction the motor is rotating.
Figure 8 Media Drive Assembly
The Print Process
Once an image has been processed and a printing bitmap created, the print cycle begins. The
Printhead and Drum are brought up to their operating temperatures and the ink levels in the ink
reservoirs are checked. Ink is added from the Ink Loader, if necessary.
In the ready state, the print process consists of the following steps:
• Drum Preparation
• Printing
– Ink Loader
– Printhead
– Drum Assembly
– Transfix System
• Purge System
• Transfix and Exiting
WARNING
Keep your fingers away from the Y-Axis drum rotation drive system; it uses a closed-
loop servo drive system and is inherently dangerous; the motor speeds up if it senses
the drive system slowing down, and fingers caught in the belts and gears can be
severely injured.
Drum Preparation
To prepare the Drum, a thin coating of silicone oil is applied to the surface of the Drum. First the
Drum is rotated. Next, the oil roller and blade of the Drum Maintenance Kit are raised into con-
tact with the Drum. To accomplish this, the Process Drive rotates the Drum Maintenance Cam-
shaft lifting the oil and wiper blade to the Drum. The cams on the ends of the camshaft push
against followers on each side of the Drum Maintenance Pivot Plate, forcing the oil roller and
blade against the Drum. The Drum is rotated against the oil saturated roller.