Laser Scan Unit (Lsu) - Sharp AR-M550N Service Manual

3. Laser scan unit (LSU)

B. Major parts and signal functions
CN-8
MFP
CONTROL
PWB
3
4
6
7
9
8
5
Signal
Code
name
PGM PGM Polygon mirror (motor)
BD BD PWB
No. Name
1 Laser control PWB
2 Cylindrical lens
3 Incidence reflection mirror
4 No. 1 mirror
5 fθ lens 1
6 fθ lens 2
CN-8 CN-6 CN-6
PCU PWB
MOTHER
PWB
BD
PGM
Name Type
Controls laser beam flashing and the output value.
Converges laser beams to focus.
Assures the optical path for laser beams.
Assures the optical path for laser beams.
Deflects laser beams so that the laser scan speeds on the both ends of the drum and that at the center
of the drum are the same.
AR-M550/M620/M700 DETAILS OF EACH SECTION 6 - 60
A. General
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.
CN-22
B30B-PHDSS-B SMP-18V-NC/SMR-18V-N
GND2 1 1 GND2
+5VLD 2 2 +5VLD
GND2 3 3 GND2
GND2 4 4 GND2
/READY 5 5 /READY
/PMCLK 6 6 /PMCLK
/START 7 7 /START
+24V1 8 8 +24V1
9 9 (NC)
(NC)
+24V1 10 10 +24V1
+5V2 11 11 +5V2
GND2 12 12 GND2
+5V2 13 13 +5V2
GND2 14 14 GND2
TEST 15 15 TEST
TEST2 16 16 TEST2
17 17 VRB
VRB
GND2 18 18 GND2
TEST3 19
1 TEST3
GND2 20
VIDEO 21 2 GND2
3 /VIDEO
GND2 22
/VIDEO 23 4 VIDEO
GND2 24 5 GND2
LSU S/H 25 6 GND2
GND2 26 7 LSU S/H
8 GND2
/LDON 27
GND2 28 9 /LDON
/SYNC 29 10 GND2
GND2 30 11 /SYNC
12 GND2
SMP-12V-NC/SMR-12V-N
10
2
1
Function/Operation
Reflects laser beams at the constant rotation speed.
Detects the laser scan start timing. This device is
used to detect a laser trouble.
Function
CN-2
B30B-PHDSS-B B6B-PH-K-S
1 1 GND2 /BRAKE
2 2 +5VLD /PMCLK
3 3 GND2 /READY
4 4 GND2 /START
5 5 /READY GND2
6 6 /PMCLK +24V1
7 7 /START
8 8 +24V1
9 9 /BRAKE
10 +24V1
10
11 11 +5V2
12 12 GND2
13 13 +5V2
14 14 GND2
LD PWB
15 15 TEST
16 16 TEST2
17 17 VRB
18 18 GND2
19 TEST3
1
20 GND2 B4B-PH-K-S
2 21 /VIDEO GND2
3 22 GND2
/SYNC
4 23 VIDEO GND2
5 24 GND2 +5V2
6 25 LSU S/H
7 26 GND2
8
27 /LDON
9 28 GND2
10 29 /SYNC
11 30 GND2
12
LSU UNIT
MODEL
CN-1
1
2
3
4
5
6
CN-3
1
2
3
4
NOTE