Sharp Z-21, Руководство по обслуживанию

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[6] COPY PROCESS
This model uses an OPC. (photoconductor) drum to form an image
on it.
1. Copy process diagram
2. Image forming process
Brief description of image forming process:
A charge is applied on the entire drum surface, onto which the
image of the original is projected by means of the copy lamp
selfoc. Where the light strikes the drum, the charge dissipates and
an electrostatic latent image is formed on the drum surface. Toner
is attracted to the electrostaticly charged areas of the drum to
form a visible image.
Step 1. Photoelectrical discharge (residual charge on the drum sur-
face is neutralized)
Step 2.
Step 3.
Change
Exposure
(a latent image is formed on the drum surface)
Step 4. Developing (the latent image on the drum is developed into
a visible image with toner)
Step 5. Transfer (the visible image, toner image, on the drum sur-
face is transferred onto the copy paper)
Step 6. The potential on the transfer paper is neutralized, and the
paper is separated.
Step 7. Cleaning (residual toner on the drum surface is collected by
the cleaning blade)
Step 8. Photoelectric discharge (residual charge on the drum sur-
face is neutralized)
3. Detailed description of image forming
process
Step 1. Photoelectric discharge
Prior to charging, light from the copy lamp is projected over the drum
surface to reduce electrical resistance of the OPC layer and neutral-
ize any residual charge.
As the electrical resistance is decreased, the positive charge in the
aluminum layer neutralizes the negative charge in the OPC layer.
Exposure
Main corona
Charge
Discharge
Drum
Cleaning
Cleaning blade
Waste toner collection
Paper exit Fusing Separation
Heat roller
Heater lamp
Transfer
Developing
Toner
Developer
Sync with
drum
Original
Copy lamp
SELFOC lens
Paper stoper
Separator pin Transfer corona
Paper feed
Resist roller
Copy lamp
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