Canon iR4570 Series Service Manual page 12

Contents
6.1.1Specifications, Control Mechanism, and Functions .................................................................................... 6- 1
6.1.2Major Components ...................................................................................................................................... 6- 2
6.1.3Construction of the Control System ............................................................................................................ 6- 2
6.2 Basic Sequence .................................................................................................................................................. 6- 6
6.2.1Basic Sequence ........................................................................................................................................... 6- 6
6.3 Various Controls................................................................................................................................................ 6- 7
6.3.1 Controlling the Laser Activation Timing .................................................................................................... 6- 7
6.3.1.1 Turning On and off the Laser Light..................................................................................................... 6- 7
6.3.1.2 Main Scanning Synchronous Control .................................................................................................. 6- 8
6.3.2 Controlling the Intensity of Laser Light...................................................................................................... 6- 9
6.3.2.1 APC Control ........................................................................................................................................ 6- 9
6.3.3 Controlling the Laser Scanner Motor........................................................................................................ 6- 10
6.3.3.1 Controlling the Laser Scanner Motor ................................................................................................ 6- 10
6.3.4 Controlling the Laser Shutter .................................................................................................................... 6- 10
6.3.4.1 Controlling the Laser Shutter............................................................................................................. 6- 10
6.4 Parts Replacement Procedure .......................................................................................................................... 6- 12
6.4.1 Laser Scanner Unit .................................................................................................................................... 6- 12
6.4.1.1 Removing the Front Cover Unit ........................................................................................................ 6- 12
6.4.1.2 Removing the Left Cover .................................................................................................................. 6- 12
6.4.1.3 Removing the Laser Unit................................................................................................................... 6- 12
Chapter 7 Image Formation
7.1 Construction....................................................................................................................................................... 7- 1
7.1.1Specifications of the Image Formation System ........................................................................................... 7- 1
7.1.2Major Components of the Image Formation System................................................................................... 7- 2
7.2 Image Formation Process .................................................................................................................................. 7- 4
7.2.1Image Formation Process (outline).............................................................................................................. 7- 4
7.2.2Image Formation Process (image formation) .............................................................................................. 7- 5
7.3 Basic Sequence .................................................................................................................................................. 7- 6
7.3.1Sequence of Operation (initial rotation) ...................................................................................................... 7- 6
7.3.2Sequence of Operation (initial rotation) ...................................................................................................... 7- 6
7.3.3Sequence of Operation (copying) ................................................................................................................ 7- 7
7.3.4Sequence of Operation (copying) ................................................................................................................ 7- 8
7.3.5Sequence of Operation (last rotation) .......................................................................................................... 7- 8
7.3.6Sequence of Operation (last rotation) .......................................................................................................... 7- 9
7.4 Image Stabilization Control............................................................................................................................. 7- 10
7.4.1Overview.................................................................................................................................................... 7- 10
7.4.2APVC Control ........................................................................................................................................... 7- 10
7.4.3ATVC Control ........................................................................................................................................... 7- 11
7.5 Drum Unit ........................................................................................................................................................ 7- 12
7.5.1 Charging Mechanism ................................................................................................................................ 7- 12
7.5.1.1 Controlling the Primary Charging Bias ............................................................................................. 7- 12
7.5.1.2 Primary Charging Roller Cleaning Mechanism................................................................................. 7- 12
7.6 Drum Cleaner Unit .......................................................................................................................................... 7- 14
7.6.1Photosensitive Drum Cleaning .................................................................................................................. 7- 14
7.7 Developing Unit............................................................................................................................................... 7- 15
7.7.1Controlling the Developing Bias ............................................................................................................... 7- 15
7.8 Toner Container ............................................................................................................................................... 7- 16