Image Formation System; Outline - Canon LBP-1120 Service Manual

IV. IMAGE FORMATION SYSTEM
A. Outline
The image formation system is the central hub of the printer, and consists of the photosensitive drum, developing unit,
charging roller, etc.
When receiving a pickup command from the interface controller, the engine controller drives the main motor to
rotate the photosensitive drum, developing cylinder, primary charging roller, and transfer charging roller.
The photosensitive drum surface is uniformly applied with a negative charge by the primary charging roller. At the
same time, the drum surface is struck by the laser beam that has been modulated by the video signals. This forms a
latent image on the photosensitive drum.
The latent image formed on the photosensitive drum is developed into a visible image on the developing cylinder
with toner and then transferred onto print paper by the transfer charging roller. The residual toner on the photosensitive
drum surface is scraped off by the cleaning blade. The potential on the drum is made uniform by the primary charging
roller in preparation for another latent image.
Primary charging roller
Interface
controller
PCB
Laser beam
Photosensitive drum
Transfer charging roller
/VDO
Engine
controller
PCB
VDO
Figure 2-4-1
CHAPTER 2
Developing cylinder
PR
TR
DV
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