Transfer Belt Speed Control - Ricoh B202 Service Manual

Transfer belt speed control

This machine uses two devices (Rotation encoder and transfer belt mark sensor) to
control the transfer belt speed.
Rotation Encoder
An encoder [C] is on one of the rollers. This encoder checks the rotation speed of
the transfer belt. The controller analyzes the signals from the encoder. Then it
adjusts the rotation speed of the transfer belt.
The encoder contains a disk that has 300 notches on its surface [B]. These
notches are read by the sensor [A]. The controller counts the number of notches
that the sensor has read in the unit of time. If the sensor has read an unusually
large number of notches or an unusually small number of notches, the controller
ignores such unusual signals. Therefore, incorrect reading does not affect the
rotation speed.
Number of notches
(read by the sensor)
Filter H: The number of notches read by the sensor when the rotation speed of the transfer belt is
at its highest possible value.
Filter L: The number of notches read by the sensor when the rotation speed of the transfer belt is
at its lowest possible value.
SM
IMAGE TRANSFER AND PAPER SEPARATION
[A]
Ignored
Ignored
6-83
[C]
[B]
B178D576.WMF
Filter H
Filter L
Time
B178D577.WMF
B202/B178/B180