Ricoh LDD250, Service Manual

Page: 391 / 459

DRUM
SM 6-69 C262/C265
Detailed
Des
cription
s
6.7.3 DRUM SHIFT MECHANISM FOR IMAGE SIDE-TO-SIDE SHIFT
The image side-to-side shift function shifts the outer drum sleeve (with master)
from front to back.
The shifting mechanism is inside the drum. It consists of the drum shift motor [A]
and a rack and pinion mechanism.
The motor can turn in either direction by the image shift amount set at the
operation panel. The motor moves the rear drum flange [B] via the rack and pinion,
as shown. At the same time, it rotates the pulse disk. This allows the drum shift
sensor [C] to generate pulse signals for sending to the CPU. The CPU detects the
amount of shift with these signals and controls motor on/off time.
The maximum shift range, in both directions, is 10 mm from home position. The
drum shift HP sensor [D] ensures that the outer drum sleeve returns to the home
position.
When the outer sleeve returns to the home position, it activates the sensor,
stopping the drum shift motor.
C262D059.WMF
[A]
[B]
[C]
[D]
Front
Rear