HL-8050N SERVICE MANUAL
iii
CHAPTER 3 THEORY OF OPERATION ................................................ 3-1
1. ELECTRONICS ......................................................................................................... 3-1
1.1 General
Block Diagram.................................................................................................... 3-1
1.2 Main PCB ......................................................................................................................... 3-2
1.2.1 Outline................................................................................................................................. 3-2
1.2.2 Circuit.................................................................................................................................. 3-4
2. MECHANICS ............................................................................................................. 3-6
2.1 Summary of Print Process ............................................................................................... 3-6
2.2 Flow
of
Print Data............................................................................................................. 3-9
2.3 Driving Force Transmission Path................................................................................... 3-10
2.3.1 Main Motor ........................................................................................................................ 3-10
2.3.2 Motor ASSY Exit ............................................................................................................... 3-10
2.3.3 Gear Layout ...................................................................................................................... 3-11
2.4 Paper
Transport ............................................................................................................. 3-14
2.4.1 Paper
Transport Path........................................................................................................ 3-14
2.4.2 Layout of Paper Transport Path ........................................................................................ 3-15
2.5 Actions of Main Functional Components ....................................................................... 3-17
2.5.1 Paper Cassette ................................................................................................................. 3-17
2.5.2 Paper Feeder .................................................................................................................... 3-20
2.5.3 Engine............................................................................................................................... 3-22
2.5.4 Fuser................................................................................................................................. 3-25
2.5.5 500 Paper Exit & Option Face Up Tray ............................................................................ 3-27
2.5.6 Drive ................................................................................................................................. 3-28
2.5.7 Electrical .......................................................................................................................... 3-29
2.6 Control............................................................................................................................ 3-31
2.6.1 Control
of Paper Size ........................................................................................................ 3-31
2.6.2 ROS
Control...................................................................................................................... 3-31
2.6.3 Fuser
Control .................................................................................................................... 3-32
2.7 Schematic Diagrams of Safety System ......................................................................... 3-33
CHAPTER 4 DISASSEMBLY AND RE-ASSEMBLY ............................. 4-1
1. SAFETY
PRECAUTIONS.......................................................................................... 4-1
2. DISASSEMBLY
FLOW .............................................................................................. 4-2
3. DISASSEMBLY
PROCEDURE ................................................................................. 4-3
3.1 Drum Unit ......................................................................................................................... 4-3
3.2 Paper
Cassette 150 ......................................................................................................... 4-3
3.3 Paper
Cassette 550 ....................................................................................................... 4-10
3.4 Face-up
Output Tray ASSY .......................................................................................... 4-16
3.5 Stopper
FSR/Cover Rear 500........................................................................................ 4-16
3.6 Disassembly of the Cover Rear 500 .............................................................................. 4-17
3.7 Cover Rear..................................................................................................................... 4-20
3.8 Cover Right .................................................................................................................... 4-21
3.9 Cover Left....................................................................................................................... 4-22
3.10 Cover Exit 500................................................................................................................ 4-22
3.11 500 Exit ASSY................................................................................................................ 4-23
3.12 Cover Top/Operation Panel ........................................................................................... 4-29
3.13 Cover Front ................................................................................................................... 4-31
