Specifications

2. DRUM CHARGE
2.1 OVERVIEW
This copier uses a single wire scorotron and a highly sensitive OPC drum [A].
The corona wire [B] generates a corona of negative ions when the CC/B/G
power pack applies a high voltage. A stainless steel grid plate [C] makes the
corona charge uniform. The drum coating receives a uniform negative charge
as it rotates past the corona unit.
The exhaust blower, located above the copy exit, causes a flow of air from
the upper area of the development unit through the charge corona unit. This
prevents uneven build-up of negative ions that can cause uneven image
density. The exhaust blower runs at half speed when in the stand-by
condition and runs at full speed while copying.
The exhaust blower has an ozone filter (active carbons) which adsorbs ozone
(O3) generated by the corona discharge. The ozone filter decreases in
efficiency over time as it adsorbs ozone. The ozone filter should be replaced
at every 60,000 copies.
The flow of air around the charge corona wire may deposit paper dust or
toner particles on the corona wire. These particles may interfere with
charging and cause low density bands on copies. The wire cleaner cleans
the corona wire when the operator slides the corona unit in and out.
[C]
[A]
[C]
[B]
[A]
1 December 1990
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