Xerox Nuvera 100, Service Manual

Page: 47 / 304

General Information 1-47
840-4-47
Home
sensor
Temperature
sensor (~55
°
C)
Drum
Fan
Belt drive
Warning: Closed-loop
servo drive
Servo motor
Paper/drum
heater
Entry
assembly
Encoder
Encoder
disk
Home
flag
Transfix roller
Figure 1-16. Drum/Transfix Assembly
An encoder disk and sensor on the left end of the drum monitors the
drum’s speed as well as its “home” position. The drum heater heats
the surface of the drum to about 55
o
C (131
o
F) for imaging. A
temperature sensor in contact with the drum surface monitors the
drum temperature. The main board interprets the sensor’s signal and
turns on the drum heater and drum fan to heat the drum, or turns on
the drum fan alone to cool the drum.
The drum is driven by a closed-loop servo motor which, through a
double reduction belt drive, rotates the drum at a high speed for
imaging and a constant low speed for image transfer to paper.
WARNING
Keep your fingers away from the drum drive system; it uses a
closed-loop drive system. A closed-loop servo drive system is
inherently dangerous. 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.