Canon imageCLASS LBP325dn, Service Manual

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Image Formation System
Image Formation Process
■ Outline
The image formation process consists of the following seven steps divided among five functional blocks:
Latent image formation block
• Step 1: Primary charging
• Step 2: Laser-beam exposure
Developing block
• Step 3: Developing
Transfer block
• Step 4: Transfer
• Step 5: Separation
Fixing block
• Step 6: Fixing
Drum cleaning block
• Step 7: Drum cleaning
2. Laser-beam exposure
Fixing
6. Fixing Delivery
7. Drum cleaning
3. Developing
1. Primary charging
Pickup 4.Transfer 5. Separation
Transfer
Latent image formation
Media path
Direction of
the drum rotation
Block
Step
Drum cleaning
Developing
■ Latent image formation block
During the two steps that comprise this block, an invisible latent image is formed on the photosensitivedrum.
Step 1: Primary charging
To prepare for latent image formation, the surface of the photosensitive drum is charged with a uniform negative potential. The
primary charging bias is applied to the primary charging roller and the roller charges the drum directly.
Primary charging bias Photosensitive drum
Primary charging roller
2. Technical Explanation (Device)
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