Brother HL-3450CN Service Manual page 55

CHAPTER 4 STRUCTURE OF SYSTEM COMPONENTS
CHAPTER 4 STRUCTURE OF SYSTEM COMPONENTS.................. 4-3
1. BASIC STRUCTURE ....................................................................................... 4-3
1.1 Mechanical Structures ............................................................................................................ 4-3
1.2 Basic Mechanism of Color Printing ......................................................................................... 4-5
1.2.1 Principle of color printing .................................................................................................. 4-5
1.2.2 Basic color printing process ............................................................................................. 4-5
1.3 Structure of the OPC Belt ....................................................................................................... 4-7
1.4 Print System and Transfer System ......................................................................................... 4-8
1.4.1 Structure of the printer...................................................................................................... 4-9
1.4.2 Basic structure of the printing system ............................................................................ 4-10
1.4.3 Details of each process .................................................................................................. 4-12
1.5 Scanning System .................................................................................................................. 4-23
1.6 Paper Transportation System ............................................................................................... 4-25
1.6.1 Outline ............................................................................................................................ 4-25
1.6.2 Structure of paper transportation system ....................................................................... 4-25
1.7 Fusing Unit............................................................................................................................ 4-26
1.7.1 Structure......................................................................................................................... 4-26
1.7.2 Fusing process ............................................................................................................... 4-27
2. STRUCTURE OF THE CONTROL SYSTEM................................................. 4-28
2.1 Basic Structure - Electrical System and Functions ............................................................... 4-28
2.2 Control System - Control of the Print Process ...................................................................... 4-37
2.3 Main PCB (Video Controller PCB) ........................................................................................ 4-46
2.3.1 Outline ............................................................................................................................ 4-46
2.3.2 Circuit ............................................................................................................................. 4-48
2.4 Low-voltage Power Supply Unit ............................................................................................ 4-60
2.5 High-voltage Power Supply Unit ........................................................................................... 4-63
2.6 Connection Diagram ............................................................................................................. 4-65
CONTENTS
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