Oki OKIFAX OF5900, Maintenance Manual

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R76-/R76-2
OKIFAX 5700/5900 A3 - 31
(4) Developing
Toner is attracted to the electrostatic latent image on the image drum surface,
converting it into a visible toner image. Developing takes place through the contact
between the image drum and the developing roller.
1 As the toner supply roller rotates while rubbing on the developing roller, a
friction charge is generated between the developing roller and the toner,
allowing the toner to be attracted to the developing roller (the developing roller
surface is charged positive and the toner, negative.)
-300V
-750V -100V -750V -750V
Developing roller
Toner
Image drum
-100V
Exposed
part
Exposed
part
An illustration of activities at the contact point of the
image drum surface and the developing roller (arrow
marks denote the direction of the electrical field).
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Toner supply roller
2 The toner attracted to the developing roller is scraped off by the doctor blade,
forming a thin coat of toner on the developing roller surface.
3 Toner is attracted to the exposed portion (low-potential part) of the image drum
at the contact of the image drum and the developing roller, making the electro-
static latent image visible.
Doctor blade
Charge roller
Image drum
Developing roller