Brother HL-820 - Page 5

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2.3 Sensors...................................................................................................................................II-29
2.3.1 Cover Sensor.............................................................................................................II-29
2.3.2 Toner Empty Sensor..................................................................................................II-29
2.4 Drum Unit................................................................................................................................II-30
2.4.1 Photosensitive Drum .................................................................................................II-30
2.4.2 Primary Charger........................................................................................................II-30
2.4.3 Developer Roller........................................................................................................II-30
2.4.4 Transfer Roller...........................................................................................................II-30
2.4.5 Cleaner Roller............................................................................................................II-30
2.4.6 Erase Lamp ..............................................................................................................II-30
2.5 Print Process ..........................................................................................................................II-30
2.5.1 Charging ...................................................................................................................II-30
2.5.2 Exposure Stage.........................................................................................................II-31
2.5.3 Developing.................................................................................................................II-32
2.5.4 Transfer.....................................................................................................................II-32
2.5.5 Drum Cleaning Stage ................................................................................................II-33
2.5.6 Erasing Stage............................................................................................................II-33
2.5.7 Fixing Stage...............................................................................................................II-33
CHAPTER III DISASSEMBLY AND REASSEMBLY.......................................III-1
1. SAFETY PRECAUTIONS..................................................................................................III-1
2. DISASSEMBLY FLOW......................................................................................................III-2
3. DISASSEMBLY PROCEDURE .........................................................................................III-3
3.1 Output Tray ASSY ...................................................................................................................III-3
3.2 Drum Unit.................................................................................................................................III-3
3.3 Top Cover................................................................................................................................III-4
3.4 Rear Cover ..............................................................................................................................III-4
3.5 MP Sheet Feeder ASSY ..........................................................................................................III-5
3.6 Fixing Unit................................................................................................................................III-6
3.7 Scanner Unit............................................................................................................................III-8
3.8 Main PCB ASSY ....................................................................................................................III-10
3.9 Base Plate ASSY...................................................................................................................III-10
3.10 Panel Sensor PCB ASSY ......................................................................................................III-11
3.11 Low-voltage Power Supply PCB ASSY .................................................................................III-12
3.12 High-voltage Power Supply PCB ASSY.................................................................................III-13
3.13 Sub Fan Motor ASSY ............................................................................................................III-14
3.14 Fan Motor ASSY ...................................................................................................................III-14
3.15 Drive Unit ...............................................................................................................................III-15
3.16 Main Motor ASSY ..................................................................................................................III-16
3.17 Sub Motor ASSY....................................................................................................................III-16
3.18 Paper Support........................................................................................................................III-17
3.19 Extension Support Wire .........................................................................................................III-17
4. PACKING........................................................................................................................III-18