Sharp MX-4100N Service Manual page 486

B. Image density detection and resist detection
Image density detection and image resist detection are performed
by the sensors arranged on the front frame side and the rear frame
side.
(1) Function and operation of the color image density
sensor/image resist sensor F (REGS F) provided
on the front frame side
When the process control is performed with one sensor, the color
toner patch density is detected.
When the image resist adjustment is performed, the image resist
shift on the front frame side is detected.
The shutter plate is provided on the sensor. The shutter plate is
closed before operation of the process control. The sensor sensitiv-
ity adjustment is performed by using the shutter plate as the refer-
ence reflection plate.
The operation of the shutter plate is controlled by the process con-
trol shutter solenoid (PCSS).
(2) Function and operation of the black image density
sensor/image resist sensor R (REGS R) provided
on the rear frame side
When the process control is performed with one sensor, the black
toner patch density is detected.
When the image resist adjustment is performed, the image resist
shift on the rear frame side is detected.
3.
A. Primary transfer unit
1) Open the front cover.
2) Open the right door.
3) Loosen the blue screw.
4) Turn the blue screw (A) counterclockwise. Making sure that
the lock is released (B), open and then pull out the drum posi-
tioning unit.
* Failure to complete this step may damage the intermediate
MX-5001N TRANSFER SECTION L – 4
Disassembly and assembly
transfer belt.
A
B