Specifications

C-14
PagePro25
4-2. Charging Section
Before producing an electrostatic latent image on the surface of the PC drum with a laser beam, the PC drum is charged
by static electricity with the rotating charge bush so that the surface of the PC drum is negatively charged. The charging
system uses the rotating charge brush system. Since this charging system can apply charge directly to the PC drum,
charging is possible at a low voltage, producing negligible amount of ozone.
The negative level of the surface of the PC drum will be reduced when a laser beam is applied.
Note: For the laser beam emission, see 3 “Print Head Unit (Exposure Section)”.
4-3. Development Section
The development section feeds toner to the electrostatic latent image on the surface of the PC drum to produce a visible
toner image.
The toner in the toner hopper is agitated by the two agitator blades to feed toner to the toner feed roller. Then, the toner is
fed to the sleeve roller which is negatively biased. Accordingly, the toner is negatively charged by the sleeve roller. The
toner regulating plates acts to regulate the amount of toner fed to the sleeve roller. To regulate the toner, a voltage lower
than the sleeve roller is applied to the toner regulating plates.
Since the toner is negatively charged by the sleeve roller, the toner will stick to the electrostatic latent image where the
negative voltage is reduced. On the other hand, toner does not stick to the part where no laser beam is applied since the
part maintains the negatively charged voltage with the charge brush.
The following illustrates an example where the letter “A” is written by the laser beam and toner sticks onto the letter “A” on
the surface of the PC drum.
Laser beam
Charge Brush
PC drum ground
PC Drum
Charge bias
Developer bias
Agitator Blade
Ton er
PC Drum
Sleeve Roller
Toner bias
Mirror
Seal bias
Toner Empty Sensor
Mirror/Window Cleaner
Toner Regulating Plate
PC Drum
Sleeve Roller
Seal
Toner Feed Roller