Sharp MX-M550U Service Manual page 337

2. Operational descriptions
A. Outline
This section performs the following operations.
Image data sent from the MFP (image process circuit) through the
mother board and PCU are converted into laser beams to radiate
onto the drum surface.
[Laser optical path]
* This unit must not be disassembled in the market.
B. Polygon mirror motor
Number of
Model
mirror surface
55/62ppm 14 surfaces
70ppm 14 surfaces
The number of mirror surfaces and the motor RPM are reduced to
reduce noises and increase reliability.
C. Outline of LSU specifications
Effective scan width : 297 mm
Resolution : 600 dpi
Beam diameter : Main scan = 60 to 85 m
Sub scan = 75 to 110 m
Laser power : 55/62ppm: 0.385
70ppm: 0.480
Laser power : 770 to 795 nm
Rotating
Bearing Remarks
speed
34000 rpm AIR Superior in
silence
40000 rpm AIR
0.04mW
0.04mW
MX-M700N LSU SECTION i – 2
3. Disassembly and assembly
A. Laser scan unit (LSU)
No.
1 LSU
(1) LSU
(1)
1) Pull out the multi paper feed tray, and remove the manual
paper feed cover F.
2) Pushing the lower part, remove the right cabinet center.
Unit