Ricoh J001 Service Manual page 165

6.7.7 TRANSPORT BELT
A high voltage power pack [A] charges the
charge roller the transport belt [B].
The charge roller applies a bias charge to
the transport belt. This static charge
makes the paper adhere to the transport
belt so the paper does not shift during
transport and printing.
A temperature/humidity sensor, mounted
near the charge roller, monitors the
temperature and humidity near the charge
roller. The reading of this sensor is
matched with values in a lookup table (see
next page) that is cross-indexed with temperature and humidity readings. The
values read from the table are used to adjust the width of the bias (bias pitch)
applied to the transport belt. This operation, called belt charge control, operates
within the following ranges of temperature and humidity:
Temperature: 0C to 35C (32F to 95F)
Humidity: 0% to 100%
The machine uses the feedback of the temperature/humidity sensor to reduce the
width of the charge applied to the transport belt below the print heads. This
reduces the size of the electrical field to the smallest size that can still provide the
optimum charge to keep the paper on the belt at the leading edge, center, and
trailing edge of the paper without interfering with the operation of the print nozzles.
Belt charge control is done for every paper feed station (Tray 1, Tray 2, and
bypass) and for every paper type (normal paper, envelopes, thick paper, and
OHP).
The sharp curvature of the paper path separates the paper from the transport belt
at the time paper is fed out the paper exit.
SM
CÓPIA NÃO CONTROLADA
PAPER FEED, TRANSPORT, OUTPUT
Adjusted in 2.5C (4.5F) steps
Adjusted in 10% steps
6-33
CÓPIA NÃO CONTROLADA
[A]
[B]
G707D939.BMP
J001/J003