Development Bias; Mechanism; Correction For Paper Width And Thickness (By-Pass Tray Only) - Ricoh B264 Service Manual

DEVELOPMENT

6.9.4 DEVELOPMENT BIAS

Mechanism

Black areas of the latent image are at a
low negative charge (about –150 V) and
white areas are at a high negative
charge (about –850 V).
To attract negatively charged toner to the
black areas of the latent image on the
drum, the high voltage supply board [A]
applies a bias of –560 volts to the
development roller throughout the image
development process. The bias is
applied to the development roller shaft
[B] through the bias terminal spring [C]
and bias terminal [D].
The development bias voltage (-560 V) can be adjusted with SP2-201
(Development Bias).

Correction for paper width and thickness (by-pass tray only)

The by-pass tray can be used for non-standard paper narrow than sizes accepted
by the paper trays. Thicker paper, OHP sheets, etc. can also be loaded in the by-
pass tray but adjustments must be performed with the SP modes listed below in
order to avoid jams and misfeeds.
SP Mode
SP2201 1 Development Bias
SP2309 1 Paper Lower Width [a]
SP2309 2 Paper Upper Width [b]
SP2914 3
Process Control Setting (Bγ)
SP2914 4
Process Control Setting (Bδ)
The way that these SP modes are used is shown below.
0 mm
SP2201 1 + SP2914 3
Default: -560 + 200 V
For example, with the default settings, if the paper width fed from the by-pass tray
is 200 mm, the development bias voltage will be –560 + 50 V.
B264/B265
SP Name
SP 2309 1
Default: 150 mm
Voltage:
SP2201 1 + SP2914 4
Default: -560 + 50 V
[B]
Width 216 - 297 mm (Default: -560V)
Width limit (Default: 150 mm)
Width limit (Default: 216 mm)
Adjust 10V/step (Default: 200V)
Adjust 10V/step (Default: 50V)
SP 2309 2
Default: 216 mm
Voltage:
Default: -560 V
6-62
[A]
[D]
297 mm
Voltage:
SP2201 1
B195D915.WMF
[C]
B195D942.WMF
SM