Canon iR8500 Service Manual page 10

7.3.3 Controlling the Laser Scanner Motor....................................................................................................................... 7- 7
7.3.3.1 Outline...................................................................................................................................................................................... 7- 7
7.4 Parts Replacement Procedure ...................................................................................................................7- 9
7.4.1 Laser Scanner Unit.................................................................................................................................................. 7- 9
7.4.1.1 Removing the Laser Unit ......................................................................................................................................................... 7- 9
7.4.1.2 Removing the Laser Unit ......................................................................................................................................................... 7- 9
7.4.1.3 Removing the Laser Unit ......................................................................................................................................................... 7- 9
7.4.1.4 Removing the Laser Unit ....................................................................................................................................................... 7- 10
7.4.1.5 Points to Note When Replacing the Laser Unit...................................................................................................................... 7- 11
7.4.1.6 Points to Note When Replacing the Laser Unit...................................................................................................................... 7- 11
7.4.2 BD Unit .................................................................................................................................................................. 7- 11
7.4.2.1 Removing the BD Unit ........................................................................................................................................................... 7- 11
7.4.2.2 Removing the BD Unit ........................................................................................................................................................... 7- 11
Chapter 8 Image Formation
8.1 Construction ...............................................................................................................................................8- 1
8.1.1 Outline ..................................................................................................................................................................... 8- 1
8.1.2 Outline of the Image Formation System(iR105) ...................................................................................................... 8- 1
8.1.3 Major Components .................................................................................................................................................. 8- 3
8.1.4 Pre-Transfer Exposure LED .................................................................................................................................... 8- 4
8.1.5 Pre-Transfer Exposure LED .................................................................................................................................... 8- 4
8.1.6 Pre-Transfer Exposure LED .................................................................................................................................... 8- 4
8.1.7 Pre-Transfer Exposure LED .................................................................................................................................... 8- 5
8.1.8 Addition of the Developing Fan(iR105).................................................................................................................... 8- 5
8.2 Basic Sequence..........................................................................................................................................8- 6
8.2.1 Basic Sequence....................................................................................................................................................... 8- 6
8.2.2 Basic Sequence....................................................................................................................................................... 8- 6
8.3 Potential Control .........................................................................................................................................8- 7
8.3.1 Outline ..................................................................................................................................................................... 8- 7
8.3.2 Basic Sequence....................................................................................................................................................... 8- 7
8.3.3 Basic Sequence....................................................................................................................................................... 8- 8
8.3.4 Determining the Optimum Grid Bias........................................................................................................................ 8- 9
8.3.5 Grid Bias Corrective Control.................................................................................................................................... 8- 9
8.3.6 Determining the Optimum Laser Output................................................................................................................ 8- 10
8.3.7 Laser Output Corrective Control............................................................................................................................ 8- 10
8.3.8 Determining the Optimum Developing Bias........................................................................................................... 8- 11
8.3.9 Potential Control for Transparency Mode.............................................................................................................. 8- 11
8.3.10 Target Potential Correction in Each Mode........................................................................................................... 8- 12
8.3.11 Target Potential Correction in Each Mode........................................................................................................... 8- 14
8.4 Charging Mechanism................................................................................................................................8- 16
8.4.1 Primary Charging Mechanism ............................................................................................................................... 8- 16
8.4.1.1 Outline.................................................................................................................................................................................... 8- 16
8.4.1.2 Primary Charging Assembly Cleaning Mechanism................................................................................................................ 8- 16
8.4.1.3 Others .................................................................................................................................................................................... 8- 17
8.4.2 Dust-Collecting Roller Bias.................................................................................................................................... 8- 17
8.4.2.1 Outline.................................................................................................................................................................................... 8- 17
8.4.3 Pre-Transfer Charging Mechanism ....................................................................................................................... 8- 18
8.4.3.1 Outline.................................................................................................................................................................................... 8- 18
8.4.3.2 Controlling the Output to Suit the Environment (fuzzy control) .............................................................................................. 8- 19
8.4.3.3 Pre-Transfer Charging Assembly Cleaning Mechanism ........................................................................................................ 8- 20
8.4.3.4 Others .................................................................................................................................................................................... 8- 20
8.5 Drum Cleaner Unit ....................................................................................................................................8- 22
8.5.1 Outline ................................................................................................................................................................... 8- 22
8.5.2 Outline ................................................................................................................................................................... 8- 22
8.5.3 Detecting the Waste Toner (case full condition).................................................................................................... 8- 23
8.6 Developing Assembly ...............................................................................................................................8- 25
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