7.4.1 Overview ..................................................................................................................................................................7- 5

7.4.2 Copier/Printer Potential Control ...............................................................................................................................7- 5

7.4.3 Determining the Primary Current .............................................................................................................................7- 7

7.4.4 Determining the Laser Output..................................................................................................................................7- 8

7.4.5 Determining the Developing Bias.............................................................................................................................7- 8

7.4.6 APC Correction ........................................................................................................................................................7- 9

7.4.7 Adjusting the Density in Various Modes ................................................................................................................7- 10

7.5 Charging Mechanism ............................................................................................................................... 7- 11

7.5.1 Controlling Pre-Exposure LED...............................................................................................................................7- 11

7.5.1.1 Pre-Exposure LED Control .................................................................................................................................................... 7- 11

7.5.2 Primary Charging Mechanism................................................................................................................................7- 11

7.5.2.1 Overview ................................................................................................................................................................................ 7- 11

7.5.2.2 Primary Charging Assembly Cleaning Mechanism................................................................................................................ 7- 11

7.5.2.3 Others .................................................................................................................................................................................... 7- 12

7.5.3 Dust-Collecting Roller Bias ....................................................................................................................................7- 12

7.5.3.1 Overview ................................................................................................................................................................................ 7- 12

7.5.4 Pre-Transfer Charging Mechanism........................................................................................................................7- 13

7.5.4.1 Outline.................................................................................................................................................................................... 7- 13

7.5.4.2 Controlling the Output to Suit the Environment (fuzzy control) .............................................................................................. 7- 13

7.5.4.3 Pre-Transfer Charging Assembly Cleaning Mechanism ........................................................................................................ 7- 14

7.5.4.4 Others .................................................................................................................................................................................... 7- 14

7.6 Drum Cleaner Unit.................................................................................................................................... 7- 16

7.6.1 Outline....................................................................................................................................................................7- 16

7.6.2 Detecting the State (full) of the Waste Toner Case ...............................................................................................7- 16

7.7 Developing Assembly ............................................................................................................................... 7- 18

7.7.1 Controlling the Developing Assembly Drive...........................................................................................................7- 18

7.7.2 Controlling the Developing Bias.............................................................................................................................7- 18

7.7.3 Detecting the Toner Level and Controlling Toner Supply ......................................................................................7- 19

7.8 Transfer Mechanism................................................................................................................................. 7- 21

7.8.1 Transfer Charging Mechanism...............................................................................................................................7- 21

7.8.1.1 Outline.................................................................................................................................................................................... 7- 21

7.8.1.2 Controlling the Output to Suit the Environment (fuzzy control) .............................................................................................. 7- 21

7.8.1.3 Transfer Charging Assembly Cleaning Mechanism............................................................................................................... 7- 21

7.8.1.4 Others .................................................................................................................................................................................... 7- 22

7.9 Separation Mechanism............................................................................................................................. 7- 23

7.9.1 Separation Charging Mechanism...........................................................................................................................7- 23

7.9.1.1 Outline.................................................................................................................................................................................... 7- 23

7.9.1.2 Correcting the Output to Suit the Environment and the Drum Surface Potential ................................................................... 7- 23

7.9.1.3 Others .................................................................................................................................................................................... 7- 24

7.10 Parts Replacement Procedure ............................................................................................................... 7- 25

7.10.1 Process Unit.........................................................................................................................................................7- 25

7.10.1.1 Removing the Primary Fan Duct .......................................................................................................................................... 7- 25

7.10.1.2 Removing the Developing Assembly ................................................................................................................................... 7- 25

7.10.1.3 Removing the Process Unit ................................................................................................................................................. 7- 25

7.10.1.4 Mounting the Process Unit ................................................................................................................................................... 7- 26

7.10.2 Pre-Exposure Lamp .............................................................................................................................................7- 27

7.10.2.1 Removing the Primary Fan Duct .......................................................................................................................................... 7- 27

7.10.2.2 Removing the Developing Assembly ................................................................................................................................... 7- 27

7.10.2.3 Removing the Process Unit ................................................................................................................................................. 7- 28

7.10.2.4 Removing the Primary Charging Assembly ......................................................................................................................... 7- 29

7.10.2.5 Removing the Potential Sensor Assembly ........................................................................................................................... 7- 29

7.10.2.6 Removing the Pre-Exposure Lamp Unit............................................................................................................................... 7- 29

7.10.2.7 Cleaning the Primary Anti-Stray Sheet ................................................................................................................................ 7- 30

7.10.3 Primary Charging Assembly.................................................................................................................................7- 30

7.10.3.1 Removing the Primary Fan Duct .......................................................................................................................................... 7- 30

7.10.3.2 Removing the Primary Charging Assembly ......................................................................................................................... 7- 30

7.10.4 Pre-Transfer Charging Assembly.........................................................................................................................7- 31

7.10.4.1 Removing the Primary Fan Duct .......................................................................................................................................... 7- 31

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