Bias Control (After Each Page)
After each page, the machine re-
moves toner from the development
roller and returns it to the develop-
ment unit. To do this, -400V is
applied to the development roller,
but no bias is applied to the toner
application roller.
Toner does not transfer to the devel-
opment roller at “A”, but remains on
the toner application roller when it
passes between the two rollers.
The remaining toner on the develp-
ment roller does not transfer to the
drum at “B”, but transfers to the
toner application roller at “C”.
In some cases, positively charged
toner may transfer to the drum in
this condition. So, a positive current
is applied to the transfer roller after
each page, so that the positively
charged toner does not transfer to
the transfer roller.
- 750 V
- 400V
GND
- 400V
Drum
Development
Roller
Toner
Application
Roller
A
B
C
H516D551.wmf
Development Roller
Toner Application Roller
GND
- 750 V
- 400V
Drum Surface Voltage
Toner
H516D556.wmf
August 2nd,1995
DETAILED SECTION DESCRIPTIONS
PRINTING
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