Printronix L5535, Руководство по обслуживанию

Страница: 119 / 358

Principles Of Developing
II–119
When the AC bias makes the developing roller surface potential positive, the
electric field between the drum and the developing roller is stronger than the
magnetic force between the toner and the inner-pole magnet. As a result, the
positively charged toner is attracted to the neutralized areas of the drum
surface (electrostatic latent image).
On the other hand, when the AC bias makes the developing roller surface
potential negative, the electric field between the drum and the developing
roller is weaker than the magnetic force between the toner and the inner-pole
magnet. In this case, the toner is returned to the developing roller, rather than
being attracted to the drum.
As the roller surface potential becomes alternately positive and negative, the
toner is attracted to the electrostatic latent image area on the drum surface in
a trapezoidal form during the travel within the developing section, so that a
visible image, free from density irregularities, is formed.
1.5Kv
–450v
0v
Plus Component
Minus Component
DC Bias
300v
1050v
Toner
Carrier
Positive (+) Bias
Developing
Negative (–) Bias
Photoreceptor
Drum
Roller
Developing
Roller
Photoreceptor
Drum