7.8.1Overview ................................................................................................................................................... 7- 16

7.8.2Route of Toner Supply .............................................................................................................................. 7- 17

7.8.3Controlling the Drive of the Toner Cartridge............................................................................................ 7- 18

7.8.4Toner Supply Control ................................................................................................................................ 7- 19

7.8.5Recovery Sequence ................................................................................................................................... 7- 19

7.8.6Toner Level Detection............................................................................................................................... 7- 20

7.9 Transfer Unit ................................................................................................................................................... 7- 21

7.9.1 Outline of the Transfer Unit...................................................................................................................... 7- 21

7.9.1.1 Outline ............................................................................................................................................... 7- 21

7.9.2 Controlling the Transfer Bias.................................................................................................................... 7- 21

7.9.2.1 Transfer Roller Bias Control ............................................................................................................. 7- 21

7.9.3 Cleaning .................................................................................................................................................... 7- 22

7.9.3.1 Transfer Roller Cleaning Mechanism ............................................................................................... 7- 22

7.9.4 Separation Mechanism.............................................................................................................................. 7- 22

7.9.4.1 Controlling the Static Eliminator Bias .............................................................................................. 7- 22

7.10 Transfer Mechanism...................................................................................................................................... 7- 23

7.10.1 Transfer Guide Bias ................................................................................................................................ 7- 23

7.10.1.1 Transfer Guide Bias Control ........................................................................................................... 7- 23

7.11 Photosensitive Drum Cleaning ...................................................................................................................... 7- 24

7.11.1Outline ..................................................................................................................................................... 7- 24

7.11.2Collection of Waste Toner ...................................................................................................................... 7- 24

7.11.3Checking the Waste Toner Box............................................................................................................... 7- 24

7.12 Parts Replacement Procedure ........................................................................................................................ 7- 26

7.12.1 Pre-Exposure Lamp ................................................................................................................................ 7- 26

7.12.1.1 Removing the Front Cover Unit ...................................................................................................... 7- 26

7.12.1.2 Removing the Waste Toner Case .................................................................................................... 7- 26

7.12.1.3 Removing the Toner Cartridge........................................................................................................ 7- 26

7.12.1.4 Removing the Drum Unit ................................................................................................................ 7- 27

7.12.1.5 Removing the Developing Assembly.............................................................................................. 7- 28

7.12.1.6 Removing the Upper Tray ............................................................................................................... 7- 30

7.12.1.7 Removing the Toner Cartridge Cover ............................................................................................. 7- 30

7.12.1.8 Removing the Pre-Exposure Lamp ................................................................................................. 7- 30

7.12.2 Drum Unit ............................................................................................................................................... 7- 31

7.12.2.1 Removing the Front Cover Unit ...................................................................................................... 7- 31

7.12.2.2 Removing the Waste Toner Case .................................................................................................... 7- 31

7.12.2.3 Removing the Drum Unit ................................................................................................................ 7- 32

7.12.3 Hopper Assembly.................................................................................................................................... 7- 33

7.12.3.1 Removing the Front Cover Unit ...................................................................................................... 7- 33

7.12.3.2 Removing the Waste Toner Case .................................................................................................... 7- 33

7.12.3.3 Removing the Toner Cartridge........................................................................................................ 7- 34

7.12.3.4 Removing the Drum Unit ................................................................................................................ 7- 34

7.12.3.5 Removing the Developing Assembly.............................................................................................. 7- 35

7.12.3.6 Removing the Upper Tray ............................................................................................................... 7- 37

7.12.3.7 Removing the Toner Cartridge Cover ............................................................................................. 7- 37

7.12.3.8 Removing the Pre-Exposure Lamp ................................................................................................. 7- 37

7.12.3.9 Removing the Left Cover ................................................................................................................ 7- 38

7.12.3.10 Removing the Laser Unit............................................................................................................... 7- 38

7.12.3.11 Removing the Hopper Assembly................................................................................................... 7- 39

7.12.4 Sub Hopper ............................................................................................................................................. 7- 40

Contents

Table of Contents