Chapter 4 Operation Overview - Mita DP-2800 Service Manual

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CONTENTS

Chapter 4 OPERATION OVERVIEW

Electrophotographics system .................................................................................. 4-1
Electrophotographic cycle ........................................................................................... 4-1
Amorphous-silicon drum ............................................................................................. 4-2
Charging the drum ...................................................................................................... 4-3
Toner ........................................................................................................................... 4-4
Exposure ..................................................................................................................... 4-5
Scanner unit ................................................................................................................ 4-6
Laser scanning ............................................................................................................ 4-9
Development ............................................................................................................. 4-10
Developing roller bias ................................................................................................ 4-11
Image transfer ........................................................................................................... 4-13
Fusing ....................................................................................................................... 4-14
Drum cleaning and erasing static charge .................................................................. 4-16
Typical photo process timing chart ............................................................................ 4-17
Paper feeding system ............................................................................................. 4-18
Paper control signals ................................................................................................. 4-19
Paper feeding components ....................................................................................... 4-20
Control devices ......................................................................................................... 4-21
Paper feeder control devices .................................................................................... 4-22
Printing from paper feeder cassettes ........................................................................ 4-23
Printing from the MP tray .......................................................................................... 4-24
Printing from the optional envelope feeder ............................................................... 4-25
Paper jam detection .................................................................................................. 4-26
Message display at a paper jam ............................................................................... 4-28
Print timing charts .................................................................................................. 4-29
Basic engine functions ........................................................................................... 4-32
Engine controller system ....................................................................................... 4-33
Configuration memory ............................................................................................... 4-33
High-voltage generator .............................................................................................. 4-33
Laser scanner control ................................................................................................ 4-33
Polygon motor control ............................................................................................... 4-33
Safety interlock .......................................................................................................... 4-34
The engine gate arrays ............................................................................................. 4-35
Pin assignment .......................................................................................................... 4-36
GATE ARRAY B ........................................................................................................ 4-37
Power supply ............................................................................................................. 4-40
Power distribution ...................................................................................................... 4-42
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