Drum Unit (Developing/Drum) - Canon imageRUNNER ADVANCE C350 series Service Manual

2
Technical Explanation > Image Formation System > Controls > Drum Unit (Developing/Drum)
● Primary Charging Bias Control
DC charging (no AC charging) is a distinguishing feature of the primary charging of this
machine.
The surface of the Photosensitive Drum is charged to make a uniform negative potential.
The primary charging bias (DC negative), which has been generated by the Secondary
Transfer High-voltage PCB (UN02), is applied to the Primary Charging Roller.
The primary charging bias value is determined by the following conditions on the DC
Controller PCB:
• Environment (humidity detected by the Environment Sensor (UN33))
• Life of the Photosensitive Drum
DC Controller PCB (UN04)
Secondary Transfer High-voltage PCB (UN02)
2 Technical Explanation > Image Formation System > Controls > Drum Unit (Developing/Drum)

■ Drum Unit (Developing/Drum)

● Drum Unit Overview
The Drum Unit consists of the Developing Assembly and the Drum Assembly.
Photosensitive
Drum
Primary Charging
Roller
F-2-74
Developing Assembly Drum Assembly
2-58
F-2-75
2-58