Epson Stylus COLOR 1520 Service Manual page 42

2.1. Overview...............................................................................................................2-1
2.2. Printer Mechanism Operating Principle ............................................................2-1
2.2.1.1. M-4I60 Printer Mechanism ....................................................................................... 2-1
2.2.2. Printing Mechanism .............................................................................................................. 2-2
2.2.2.1. Printhead Structure .................................................................................................. 2-2
2.2.2.2. Printing Process ....................................................................................................... 2-3
2.2.2.3. Printing Methods....................................................................................................... 2-3
2.2.3. Carriage (CR) Mechanism..................................................................................................... 2-5
2.2.4. Paper Feed Mechanism......................................................................................................... 2-6
2.2.4.1. ASF (Auto Sheet Feeder) Mechanism ..................................................................... 2-7
2.2.4.2. Tractor Mechanism................................................................................................... 2-8
2.2.4.3. Manual Feed Mechanism ......................................................................................... 2-8
2.2.5. Platen Gap (PG) Adjust Mechanism .................................................................................... 2-9
2.2.6. Ink System............................................................................................................................ 2-10
2.2.6.1. Pump Mechanism....................................................................................................2-11
2.2.7. Capping Mechanism............................................................................................................ 2-14
2.2.7.1. Wiping/CR Lock Mechanism .................................................................................. 2-15
2.3. Electrical Circuit Operation Principles ............................................................2-16
2.3.1. C172 PSB/PSE Electrical Circuit Board............................................................................. 2-16
2.3.2. C211 MAIN Control Board ................................................................................................... 2-18
2.3.2.1. Reset Circuits ......................................................................................................... 2-20
2.3.2.2. Sensor Circuits ....................................................................................................... 2-20
2.3.2.3. CR Motor Driver Circuits ........................................................................................ 2-22
2.3.2.4. PF Motor Driver Circuit........................................................................................... 2-23
2.3.2.5. Printhead Driver Circuit .......................................................................................... 2-24
2.4. Ink System Management...................................................................................2-27
2.4.1. Ink System Operations........................................................................................................ 2-27
2.4.2. Counters ............................................................................................................................... 2-28
Chapter 2
Operating Principles