Canon LBP5050 Series, Service Manual

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Chapter 2
2-5
Toner adheres to the electrostatic latent image on the photosensitive drum, which becomes visible.
Step 3: Development
Toner acquires a negative charge from the friction that occurs when the developing cylinder rotates against the developing blade. When the negatively charged
toner comes in contact with the drum, it adheres to the latent image because the drum surface has a higher potential.
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2.4.1.5 Transfer block
0018-6682
LBP5050N / LBP5050
During the three steps that comprise this block, a toner image on the photosensitive drum is transferred to the print media through the ITB.
Step 4: Primary transfer
The toner image on the photosensitive drum is transferred to the ITB. The DC positive bias is applied to the primary transfer pad. The negatively charged toner
transfers to the ITB from the drum surface.
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Step 5: Secondary transfer
The toner image on the ITB is transferred to the print media. The DC positive bias is applied to the secondary transfer roller. As the media passes between the
secondary transfer roller and the ITB, the toner image is transferred to the media.
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Step 6: Separation
The elasticity of the print media and the curvature of the ITB drive roller cause the media to separate from the ITB.
Developing blade
Developing cylinder
DC negative bias
Photosensitive drum
Unexposed area
Exposed area
Exposed area
Unexposed area
ITB
Primary transfer pad
Photosensitive
drum
DC bias
ITB
Secondary transfer roller
Media
ITB drive roller
DC bias
Static charge eliminator