Ricoh PCU10, Руководство по обучению обслуживанию

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2.7.2 Pre-cleaning corona mechanism
The PCC unit does two things: one is to improve
cleaning efficiency and the other is to help charging.
Positive discharge is applied to the toner on the OPC by
the corona wire. This gives the toner a positive charge
and the cleaning roller, which is supplied with
a negative dc bias, can easily collect the toner on the
OPC.
The PCC unit makes the surface potential of the OPC
constant (+130 volts) before charging. As a result, the
charge corona can easily make a uniform surface
potential.
2.7.3 Cleaning mechanism
Bias application method
The cleaning power pack is positioned in the rear, center
of the main body, and is wired to the rear sides of the
respective rollers. Scavenging bias is applied directly to
the scavenging roller axis. Cleaning bias is applied to
the cleaning roller, through a bearing.
The cleaning bias is also applied to the front of the unit
to obtain an accurate application through the unit casing.
PCC power pack
PCC unit
Scavenging
roller
Cleaning
bias
Cleaning power pack
Scavenging
bias
Cleaning roller
Cleaning roller
1 July 1994 Cleaning
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