42113901TH01 Rev.3
4 /
Oki Data CONFIDENTIAL
Contents
1. CONFIGURATION ...............................................................................................6
1.1 Standard Printer Configuration ............................................................................................ 6
1.2 Options................................................................................................................................. 7
2. THEORY OF OPERATION ..................................................................................9
2.1 Electrical Operation.............................................................................................................. 9
2.1.1
Summary................................................................................................................. 9
2.1.2
Microprocessor and the Peripheral Circuit .............................................................. 9
2.1.3
Initialization ........................................................................................................... 16
2.1.4
Interface Control ................................................................................................... 17
2.1.5
Print Control .......................................................................................................... 20
2.1.6
SP/LF Motor Control ............................................................................................. 22
2.1.7
Operation Panel .................................................................................................... 25
2.1.8
Alarm Circuit ......................................................................................................... 27
2.1.9
Power Supply Circuit............................................................................................. 30
2.2 Mechanical Operation ........................................................................................................ 31
2.2.1
Printhead Mechanism and Operation ................................................................... 31
2.2.2
Spacing Operation ................................................................................................ 34
2.2.3
Head Gap Adjusting .............................................................................................. 35
2.2.4
Ribbon Drive ......................................................................................................... 37
2.2.5
Paper Feed Operation .......................................................................................... 38
2.2.6
Paper Detection Mechanism ................................................................................. 48
2.2.7
Automatic Sheet Feed .......................................................................................... 50
2.2.8
Paper Park Function ............................................................................................. 52
3. ASSEMBLY/DISASSEMBLY ..............................................................................53
3.1 Precaution for Parts Replacement ..................................................................................... 53
3.2 Service Tools ..................................................................................................................... 54
3.3 Disassembly/Reassembly Procedure ................................................................................ 55
3.3.1
Printhead............................................................................................................... 57
3.3.2
Ribbon Protector ................................................................................................... 58
3.3.3
Pull-up Roller Assy................................................................................................ 59
3.3.4
Upper Cover Assy, Access Cover Assy and Sheet Guide Assy ........................... 60
3.3.5
Gear Case Assy .................................................................................................... 61
3.3.6
PC Connector ....................................................................................................... 62
3.3.7
Space Motor, Guide Roller Assy ........................................................................... 63
3.3.8
Space Rack........................................................................................................... 64
3.3.9
Carriage Cable ...................................................................................................... 65
3.3.10 Backup Roller Holder Assy ................................................................................... 66
3.3.11 Platen Assy ........................................................................................................... 67
3.3.12 Control Board (NNS) ............................................................................................. 68
3.3.13 LF Motor................................................................................................................ 69
3.3.14 Operation Panel Board (LEOP) ............................................................................ 70
3.3.15 Power Supply Board (TPW) .................................................................................. 71
3.3.16 Transformer Assy.................................................................................................. 72
3.3.17 Change Lever and Gears...................................................................................... 73
3.3.18 Carriage Shaft ....................................................................................................... 74
3.3.19 Paper Pan ............................................................................................................. 75
Содержание ML420 Series
Страница 1: ...Oki Data CONFIDENTIAL ML420 ML421 Maintenance Manual 080603F PRINTING SOLUTIONS...
Страница 117: ...42113901TH01 Rev 3 117 Oki Data CONFIDENTIAL Figure B 2 Printer General Assy 6 9 7 1 2 3 11 10 4 5 8...
Страница 122: ...42113901TH01 Rev 3 122 Oki Data CONFIDENTIAL Figure B 4 Carriage Assy 12 9 8 6 14 4 10 7 11 13 3 1...
