Canon Color iR C3480 Service Manual page 12

Chapter 6 Laser Exposure
6.1 Construction .....................................................................................................................................................6- 1
6.1.1 Specifications, Control Mechanisms, and Functions ..........................................................................6- 1
6.1.2 Overview ....................................................................................................................................................6- 1
6.2 Various Control ................................................................................................................................................6- 3
6.2.1 Controlling the Laser Activation Timing.................................................................................................6- 3
6.2.1.1 Turning On and Off the Laser Light ................................................................................................6- 3
6.2.1.2 Controlling Synchronization in Main Scanning Direction ............................................................6- 4
6.2.1.3 Controlling Synchronization in Sub Scanning Direction..............................................................6- 5
6.2.1.4 BD Correction.....................................................................................................................................6- 7
6.2.2 Controlling the Intensity of Laser Light ..................................................................................................6- 9
6.2.2.1 APC Control .......................................................................................................................................6- 9
6.2.3 Controlling the Laser Scanner Motor ...................................................................................................6- 10
6.2.3.1 Controlling the Speed of the Laser Scanner Motor....................................................................6- 10
6.3 Parts Replacement Procedure ....................................................................................................................6- 12
6.3.1 Laser Scanner Unit .................................................................................................................................6- 12
6.3.1.1 Before Removing the Laser Scanner Unit...................................................................................6- 12
6.3.1.2 Removing the Laser Scanner Unit................................................................................................6- 12
6.3.1.3 After Replacing the Laser Scanner Unit ......................................................................................6- 13
Chapter 7 Image Formation
7.1 Construction .....................................................................................................................................................7- 1
7.1.1 Specifications, Control Mechanisms, and Functions ..........................................................................7- 1
7.1.2 Overview ....................................................................................................................................................7- 2
7.1.3 Printing Process........................................................................................................................................7- 3
7.1.4 Static Image Formation Block ................................................................................................................7- 4
7.1.5 Developing Block......................................................................................................................................7- 6
7.1.6 Transfer Block ...........................................................................................................................................7- 7
7.1.7 Fixing Block ...............................................................................................................................................7- 8
7.1.8 ITB Cleaning Block...................................................................................................................................7- 9
7.1.9 Photosensitive Drum Cleaning Block ....................................................................................................7- 9
7.2 Driving and Controlling the High-Voltage System....................................................................................7- 10
7.2.1 Overview ..................................................................................................................................................7- 10
7.2.2 Generation of the Primary Charging Bias...........................................................................................7- 11
7.2.3 Generation of the Developing Bias......................................................................................................7- 11
7.2.4 Generation of the Primary Transfer Bias ............................................................................................7- 12
7.2.5 Generation of the Secondary Transfer Bias.......................................................................................7- 12
7.3 Image Stabilization Control..........................................................................................................................7- 12
7.3.1 Overview of Image Stabilization...........................................................................................................7- 12
7.3.2 Timing of Image Stabilization Control .................................................................................................7- 13
7.3.3 Drum Film Thickness Detection ...........................................................................................................7- 14
7.3.4 ATR Control.............................................................................................................................................7- 15
7.3.5 D-max Control .........................................................................................................................................7- 16
7.3.6 PASCAL Control .....................................................................................................................................7- 19
7.3.7 D-half Control ..........................................................................................................................................7- 20
7.3.8 ARCDAT Control ....................................................................................................................................7- 23
7.3.9 Color Displacement Correction Control ..............................................................................................7- 25
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