Contents6.3 Various Controls ......................................................................................................................................... 6- 36.3.1 Controlling the Laser Activation Timing ...................................................................................................................6- 36.3.1.1 Turning On and off the Laser Light .......................................................................................................................................... 6- 36.3.1.2 Main Scanning Synchronous Control....................................................................................................................................... 6- 46.3.2 Controlling the Intensity of Laser Light.....................................................................................................................6- 56.3.2.1 APC Control ............................................................................................................................................................................. 6- 56.3.3 Controlling the Laser Scanner Motor .......................................................................................................................6- 56.3.3.1 Controlling the Laser Scanner Motor ....................................................................................................................................... 6- 56.3.4 Controlling the Laser Shutter ...................................................................................................................................6- 56.3.4.1 Controlling the Laser Shutter ................................................................................................................................................... 6- 56.4 Parts Replacement Procedure ................................................................................................................... 6- 66.4.1 Laser Scanner Unit ..................................................................................................................................................6- 66.4.1.1 Removing the Front Cover Unit ............................................................................................................................................... 6- 66.4.1.2 Removing the Left Cover ......................................................................................................................................................... 6- 66.4.1.3 Removing the Laser Unit ......................................................................................................................................................... 6- 6Chapter 7 Image Formation7.1 Construction ............................................................................................................................................... 7- 17.1.1 Specifications of the Image Formation System........................................................................................................7- 17.1.2 Major Components of the Image Formation System ...............................................................................................7- 17.2 Image Formation Process .......................................................................................................................... 7- 27.2.1 Image Formation Process (outline)..........................................................................................................................7- 27.2.2 Image Formation Process (image formation)...........................................................................................................7- 37.3 Basic Sequence ......................................................................................................................................... 7- 37.3.1 Sequence of Operation (initial rotation) ...................................................................................................................7- 37.3.2 Sequence of Operation (initial rotation) ...................................................................................................................7- 47.3.3 Sequence of Operation (copying) ............................................................................................................................7- 47.3.4 Sequence of Operation (copying) ............................................................................................................................7- 57.3.5 Sequence of Operation (last rotation) ......................................................................................................................7- 57.3.6 Sequence of Operation (last rotation) ......................................................................................................................7- 57.4 Image Stabilization Control ........................................................................................................................ 7- 67.4.1 Overview ..................................................................................................................................................................7- 67.4.2 APVC Control...........................................................................................................................................................7- 67.4.3 ATVC Control...........................................................................................................................................................7- 67.5 Drum Unit ................................................................................................................................................... 7- 67.5.1 Charging Mechanism ...............................................................................................................................................7- 67.5.1.1 Controlling the Primary Charging Bias..................................................................................................................................... 7- 67.5.1.2 Primary Charging Roller Cleaning Mechanism ........................................................................................................................ 7- 77.6 Drum Cleaner Unit...................................................................................................................................... 7- 77.6.1 Photosensitive Drum Cleaning.................................................................................................................................7- 77.7 Developing Unit .......................................................................................................................................... 7- 77.7.1 Controlling the Developing Bias...............................................................................................................................7- 77.8 Toner Container ......................................................................................................................................... 7- 87.8.1 Overview ..................................................................................................................................................................7- 87.8.2 Route of Toner Supply .............................................................................................................................................7- 87.8.3 Controlling the Drive of the Toner Cartridge ............................................................................................................7- 97.8.4 Toner Supply Control ...............................................................................................................................................7- 97.8.5 Recovery Sequence...............................................................................................................................................7- 107.8.6 Toner Level Detection............................................................................................................................................7- 107.9 Transfer Unit............................................................................................................................................. 7- 107.9.1 Outline of the Transfer Unit....................................................................................................................................7- 107.9.1.1 Outline.................................................................................................................................................................................... 7- 107.9.2 Controlling the Transfer Bias .................................................................................................................................7- 107.9.2.1 Transfer Roller Bias Control................................................................................................................................................... 7- 107.9.3 Cleaning.................................................................................................................................................................7- 11