Oki ES9160, Руководство по обслуживанию

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ES9160 MFP / ES9170 MFP © 2012 OKI DATA CORPORATION All rights reserved
OUTLINE OF THE MACHINE
3 - 52
3.11.3 Functions
1. Drum
The drum is made of a cylindrical aluminum base coated with thin film of organic photoconductive
substance.
The photoconductive object becomes insulative (the electrical resistance is high) when it is not
exposed to the light and electrically conductive (the electrical resistance is low) when it is exposed to
the light. This object is called a photoconductor.
2. Main charger
The main charger in this equipment consists of a metal rod with U-shaped section, insulated blocks
at both ends of the rod and a needle electrode attached between them.
When a high voltage is applied to the needle electrode, the air around it is charged (ionized). The
ionized air then flows into the drum causing it to be charged. This phenomenon is called “corona
discharge”. At the same time, a control bias is applied to the main charger grid to control the
charging amount.
In a dark place, negative charge is evenly applied onto the drum surface by the corona discharge
and this grid. In addition, a cleaner is installed to clean up the dust attached on the needle electrode.
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Needle electrode
The needle electrode has aligned needles and their points perform the corona discharge. These
points (electrodes) discharge toward the drum in one direction to realize the more efficient
discharging comparing to the charger wire which discharges in a radial direction. Therefore, the
needle electrode enables to reduce the ozone amount.
Fig. 3-32
3. Drum cleaner
- Cleaning blade
This blade is pressed against the drum surface and scrapes off the residual toner from the drum
surface.
- Recovery blade
This blade catches the toner scraped off by the cleaning blade.
- Toner recovery auger
This auger carries the residual toner scraped off to the developer unit and reuses the toner.
Needle electrode
Main charger
Charge