Charging Section; Development Section - Epson EPL-N2700 Service Manual

EPSON EPL-N2700 / N2750

2.1.6.2 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. (Negative voltage level reduces.)
NOTE: Note: For the laser beam emission, see Section 2.1.5 "Print
Head Unit (Exposure Section)".
Charge Brush
Laser beam
Figure 2-22. Charging Section Mechanism
Operating Principles
Charge bias
PC Drum
Printer Mechanism Operating Principles

2.1.6.3 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.
Developer bias
Mirror
Toner bias
Toner Empty Sensor
Seal bias
Figure 2-23. Development Section
Revision B
Agitator Blade
Mirror/Window Cleaner
Toner Regulating Plate
PC Drum
Sleeve Roller
Bottom Seal
Toner Feed Roller
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