Konica Minolta bizhub 20 Service Manual page 40

CHAPTER 2 THEORY OF OPERATION
This chapter gives an overview of the scanning and printing mechanisms as well as the
sensors, actuators, and control electronics. It aids in understanding the basic principles of
operation as well as locating defects for troubleshooting
1. OVERVIEW ................................................................................................................... 2-1
2. ELECTRONICS ............................................................................................................. 2-2
2.1 General Block Diagram ......................................................................................... 2-2
3. MECHANICS ................................................................................................................. 2-3
3.1 Cross-section Drawing .......................................................................................... 2-3
3.2 Scanner Mechanism.............................................................................................. 2-5
3.2.1 Document scanner unit .............................................................................. 2-6
3.2.2 ADF unit ..................................................................................................... 2-8
3.3 Paper Feeding ..................................................................................................... 2-13
3.3.1 Plate-up Function of the Paper Tray ........................................................ 2-14
3.3.2 Paper supply ............................................................................................ 2-15
3.3.3 Paper registration ..................................................................................... 2-16
3.3.4 Paper eject ............................................................................................... 2-17
3.3.5 Duplex printing ......................................................................................... 2-18
3.3.6 Paper feeding from the MP tray ............................................................... 2-19
3.3.7 Paper feeding from the tray 2................................................................... 2-19
3.4 Toner Cartridge.................................................................................................... 2-20
3.4.1 Methods for Detecting Toner Life ............................................................. 2-20
3.4.2 Cartridge life ............................................................................................. 2-21
3.4.3 New toner detection ................................................................................. 2-22
3.5 Print ..................................................................................................................... 2-25
3.5.1 Basic Principle.......................................................................................... 2-25
3.5.2 Print Process ............................................................................................ 2-26
3.6 Sensors position .................................................................................................. 2-31
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