Ricoh 6010, 6110 Service manual

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Aficio Color 6010/6110

(Cattleya, A257/A269)

Service Manual

Issued March 30, 1999, Ricoh CO., LTD.

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IMPORTANT SAFETY NOTICES

PREVENTION OF PHYSICAL INJURY

1. Before disassembling or assembling parts of the copier and peripherals, make sure that the copier power cord is unplugged.

2. The wall outlet should be near the copier and easily accessible.

3. Note that some components of the copier and the paper tray unit are supplied with electrical voltage even if the main power switch is turned off.

4. If any adjustment or operation check has to be made with exterior covers off or open while the main switch is turned on, keep hands away from electrified or mechanically driven components.

5. If the Start key is pressed before the copier completes the warm-up period (the Start key starts blinking red and green alternatively), keep hands away from the mechanical and the electrical components as the copier starts making copies as soon as the warm-up period is completed.

6. The inside and the metal parts of the fusing unit become extremely hot while the copier is operating. Be careful to avoid touching those components with your bare hands.

HEALTH SAFETY CONDITIONS

1. Never operate the copier without the ozone filters installed.

2. Always replace the ozone filters with the specified ones at the specified intervals.

3. Toner and developer are non-toxic, but if you get either of them in your eyes by accident, it may cause temporary eye discomfort. Try to remove with eye drops or flush with water as first aid. If unsuccessful, get medical attention.

OBSERVANCE OF ELECTRICAL SAFETY STANDARDS

1. The copier and its peripherals must be installed and maintained by a customer service representative who has completed the training course on those models.

2. The NVRAM on the system control board has a lithium battery which can explode if replaced incorrectly. Replace the NVRAM only with an identical one. The manufacturer recommends replacing the entire NVRAM. Do not recharge or burn this battery. Used NVRAM must be handled in accordance with local regulations.

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SAFETY AND ECOLOGICAL NOTES FOR DISPOSAL

1. Do not incinerate toner bottles or used toner. Toner dust may ignite suddenly when exposed to an open flame.

2. Dispose of used toner, developer, and organic photoconductors in accordance with local regulations. (These are non-toxic supplies.)

3. Dispose of replaced parts in accordance with local regulations.

4. When keeping used lithium batteries in order to dispos e of them later, do not put more than 100 batteries per sealed box. Storing larger numbers or not sealing them apart may lead to chemical reactions and heat build-up.

LASER SAFETY

The Center for Devices and Radiological Health (CDRH) prohibits the repair of laser-based optical units in the field. The optical housing unit can only be repaired in a factory or at a location with the requisite equipment. The laser subsystem is replaceable in the field by a qualified Customer Engineer. The laser chassis is not repairable in the field. Customer engineers are therefore directed to return all chassis and laser subsystems to the factory or service depot when replacement of the optical subsystem is required.

WARNING

Use of controls, or adjustment, or performance of procedures other than those specified in this manual may result in hazardous radiation exposure.

WARNING

Turn off the main switch before attempting any of the procedures in the Laser Unit section. Laser beams can seriously damage your eyes.

CAUTION MARKING:

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TABLE OF CONTENTS

1. OVERALL MACH INE INFORMATION........................................1-1

1.1 SPECIFICATIONS.................................................................................... 1-1

1.1.1 MAJOR UNITS................................................................................. 1-1

1.1.2 BASIC SPECIFICATIONS............................................................... 1-2

1.1.3 PLATEN/ARDF ORIGINAL SIZE DETECTION................................ 1-6

1.1.4 COPY PAPER SIZES...................................................................... 1-7

1.1.5 NOISE EMISSION........................................................................... 1-8

1.1.6 POWER CONSUMPTION................................................................ 1-8

1.2 MECHANISM OVERVIEW ....................................................................... 1-9

1.2.1 IMAGE GENERATION PROCESS.................................................. 1-9

1.2.2 MAJOR UNITS AND PAPER PATH .............................................. 1-11

1.3 PARTS LAYOUT .................................................................................... 1-13

1.3.1 MAJOR UNIT LAYOUT DIAGRAM................................................ 1-13

1.4 DRIVE LAYOUT ..................................................................................... 1-14

1.5 AIR FLOW .............................................................................................. 1-15

1.5.1 AIR FLOW SYSTEM 1 ................................................................... 1-15

1.5.2 AIR FLOW SYSTEM 2 ................................................................... 1-16

1.6 ELECTRICAL PARTS LAYOUT............................................................. 1-17

1.6.1 ELECTRICAL PARTS LAYOUT 1.................................................. 1-17

1.6.2 ELECTRICAL PARTS LAYOUT 2.................................................. 1-18

1.6.3 ELECTRICAL PARTS LAYOUT 3.................................................. 1-19

1.6.4 ELECTRICAL PARTS LAYOUT 4.................................................. 1-20

1.6.5 ELECTRICAL PARTS LAYOUT 5.................................................. 1-21

1.6.6 ELECTRICAL PARTS LAYOUT 6.................................................. 1-22

1.6.7 ELECTRICAL PARTS LAYOUT 7.................................................. 1-23

1.7 ELECTRICAL PARTS DESCRIPTIONS................................................. 1-24

2. DETAILED SECTION DESCRIPTIONS.......................................2-1

2.1 PROCESS CONTROL.............................................................................. 2-1

2.1.1 OVERVIEW ..................................................................................... 2-1

2.1.2 POTENTIAL CONTROL .................................................................. 2-2

Overview.............................................................................................. 2-2

Potential Control Timing....................................................................... 2-2

2.1.3 PROCESS CONTROL γ CORRECTION ......................................... 2-4

What is process control γ?................................................................... 2-4

How is it done?..................................................................................... 2-4

Process Control γ Correction Timing.................................................... 2-5

Relationship Between Process Control γ Correction, ACC,

and Other γ Corrections.................................................................... 2-5

2.1.4 PROCESS CONTROL SELF CHECK OPERATION FLOW............ 2-6

Step 1: VSG Adjustment...................................................................... 2-7

Step 2: Generating ID Sensor Patch Patterns...................................... 2-7

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Step 3: Sensor Pattern Potential Detection.......................................... 2-8

Step 4: Sensor Pattern Density Detection............................................ 2-9

Process................................................................................................ 2-9

Step 5: Toner Amount Calculation ..................................................... 2-11

Step 6: Development Potential Calculation........................................ 2-11

Step 7: Selecting the Optimum VD, VB, VL .......................................2-12

2.1.5 TONER SUPPLY CONTROL......................................................... 2-13

Toner Supply Control Modes ............................................................. 2-13

TD Sensor Output.............................................................................. 2-14

Toner Supply Calculation...................................................................2-14

Detecting VSP for Toner Supply Control............................................ 2-14

Calculating the Amount of Toner on the Drum................................... 2-15

Toner Near End/Toner End Detection................................................ 2-15

2.2 DRUM UNIT............................................................................................ 2-17

2.2.1 MAJOR COMPONENTS................................................................ 2-17

2.2.2 DRUM UNIT DRIVE....................................................................... 2-18

Drum Drive......................................................................................... 2-18

Cleaning Drive.................................................................................... 2-18

2.2.3 CHARGE CORONA UNIT ............................................................. 2-19

2.2.4 CHARGE CORONA UNIT CLEANER............................................ 2-20

2.2.5 CLEANING MECHANISM.............................................................. 2-21

Cleaning............................................................................................. 2-21

Lubricant Application.......................................................................... 2-21

2.2.6 PRE-CLEANING CORONA (PCC) ................................................ 2-21

2.2.7 QUENCHING................................................................................. 2-22

2.2.8 CARRIER CATCHER .................................................................... 2-22

2.3 SCANNER UNIT..................................................................................... 2-23

2.3.1 OVERVIEW ................................................................................... 2-23

2.3.2 SCANNER..................................................................................... 2-24

2.3.3 SCANNER DRIVE ......................................................................... 2-25

2.3.4 COLOR CCD ................................................................................. 2-26

2.3.5 WHITE PLATE SCANNING........................................................... 2-27

2.3.6 SCANNER IPU .............................................................................. 2-27

2.3.7 ORIGINAL SIZE DETECTION....................................................... 2-28

2.3.8 OTHERS........................................................................................ 2-30

Anti-condensation Heater................................................................... 2-30

Fans................................................................................................... 2-30

2.4 IMAGE PROCESSING ........................................................................... 2-31

2.4.1 OVERVIEW ................................................................................... 2-31

2.4.2 SCANNER SECTION BLOCK DIAGRAM...................................... 2-32

2.4.3 SCANNER FUNCTIONS ............................................................... 2-33

Photoelectric Conversion................................................................... 2-33

Signal Processing (Analog ASIC)....................................................... 2-33

A/D Conversion.................................................................................. 2-33

Shading Compensation Circuit........................................................... 2-34

D/A Conversion.................................................................................. 2-35

Scan Line Correction Circuit .............................................................. 2-35

2.4.4 IPU SECTION BLOCK DIAGRAM................................................. 2-36

2.4.5 IPU FUNCTIONS...........................................................................2-37

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Scanner γ Conversion and Picture Element Correction...................... 2-37

ACS (Auto Color Selection)................................................................ 2-39

Automatic Original Type Selection..................................................... 2-40

Image Separation............................................................................... 2-41

Filtering and Color Conversion........................................................... 2-42

Magnification Processing................................................................... 2-46

Image Creation................................................................................... 2-47

Gradation Processing......................................................................... 2-49

Area Manipulation Functions.............................................................. 2-52

CPU ................................................................................................... 2-52

IPU Board Test................................................................................... 2-52

2.5 LASER EXPOSURE............................................................................... 2-53

2.5.1 OVERVIEW ................................................................................... 2-53

2.5.2 LD UNIT......................................................................................... 2-54

LD Safety Switch................................................................................ 2-54

LD Unit Configuration......................................................................... 2-55

Auto Power Control (APC)................................................................. 2-56

2.5.3 LASER OPTICS SYSTEM............................................................. 2-57

Cylindrical Lens.................................................................................. 2-57

Polygon Mirror.................................................................................... 2-57

f θ Lenses and the BTL...................................................................... 2-58

Laser Synchronization Mechanism.................................................... 2-58

Laser Exposure Control ..................................................................... 2-59

Multibeam Laser Exposure ................................................................ 2-60

Laser Diode Control Board Functions................................................ 2-60

2.6 DEVELOPMENT UNIT........................................................................... 2-61

2.6.1 OVERVIEW ................................................................................... 2-61

2.6.2 REVOLVER MECHANISM............................................................. 2-62

Revolver Drive.................................................................................... 2-63

Revolver Home Position Detection..................................................... 2-64

2.6.3 DEVELOPMENT MECHANISM..................................................... 2-65

2.6.4 DEVELOPMENT DRIVE................................................................ 2-66

2.6.5 DEVELOPER AGITATION............................................................. 2-66

2.6.6 TONER AGITATION...................................................................... 2-67

2.6.7 DEVELOPMENT BIAS................................................................... 2-67

2.6.8 TD SENSOR NONCONTACT COUPLER ..................................... 2-68

2.6.9 TONER SUPPLY MECHANISM.................................................... 2-69

2.6.10 TONER CARTRIDGE DETECTION............................................. 2-70

2.6.11 TONER CARTRIDGE SHUTTER LOCK PIN............................... 2-70

2.6.12 INCORRECT TONER INSTALLATION PREVENTION ............... 2- 70

2.6.13 TONER END SENSOR................................................................ 2-71

2.6.14 TONER END RECOVERY........................................................... 2-72

2.6.15 TONER LOOSENING..................................................................2-73

2.6.16 REVOLVER LOCK MECHANISM................................................ 2-74

2.7 TRANSFER BELT UNITS....................................................................... 2-75

2.7.1 OVERVIEW ................................................................................... 2-75

2.7.2 IMAGE TRANSFER BELT SECTION............................................ 2-76

Image Transfer Belt Drive Mechanism............................................... 2-76

Belt Tension Release Mechanism...................................................... 2-77

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Image Transfer Belt Bias.................................................................... 2-78

Belt Mark Sensor Mechanism............................................................ 2-78

Belt Cleaning Mechanism .................................................................. 2-79

Cleaning Vacuum............................................................................... 2-81

Toner Collection Mechanism.............................................................. 2-81

2.7.3 PAPER TRANSFER BELT SECTION............................................ 2-82

Paper Transfer Unit Contact/Release Mechanism............................. 2-82

Paper Transfer Belt Drive................................................................... 2-82

Paper Transfer Belt Cleaning............................................................. 2-83

Paper Transfer Bias........................................................................... 2-84

Paper Transfer Belt Discharge........................................................... 2-85

Paper Separation Mechanism............................................................ 2-85

2.8 PAPER FEED AND REGISTRATION SECTION.................................... 2-86

2.8.1 MAJOR COMPONENTS................................................................ 2-86

Diagram ............................................................................................. 2-86

2.8.2 PAPER TRAY SECTION............................................................... 2-87

Paper Feed/Separation Mechanism................................................... 2-87

Reverse Roller Release Mechanism.................................................. 2-87

Paper Feed Operation........................................................................ 2-87

Paper Lift Mechanism ........................................................................2-88

Paper End Detection..........................................................................2-89

Paper Near End Detection................................................................. 2-89

2.8.3 BY-PASS PAPER FEED SECTION............................................... 2-90

By-pass Feed Table........................................................................... 2-90

By-pass Feed Unit.............................................................................. 2-90

By-pass Paper End Sensor................................................................ 2-90

By-pass Pick-up Roller Pressure........................................................ 2-91

By-pass Pick-up/Reverse Solenoid Timing Chart...............................2-92

2.8.4 PAPER FEED DRIVE.................................................................... 2-93

Tray Feed Unit Drive.......................................................................... 2-93

Registration Roller Drive.................................................................... 2-93

By-pass Feed Unit Drive.................................................................... 2-93

2.9 TRANSPORT, FUSING, AND EXIT........................................................ 2-94

2.9.1 MAJOR COMPONENTS................................................................ 2-94

2.9.2 DRIVE MECHANISM..................................................................... 2-95

2.9.3 FUSING OVERVIEW..................................................................... 2-96

2.9.4 FUSING TEMPERATURE CONTROL........................................... 2-97

2.9.5 FUSING PRESSURE..................................................................... 2-97

2.9.6 OIL SUPPLY.................................................................................. 2-98

2.9.7 CLEANING MECHANISM.............................................................. 2-98

2.9.8 PAPER EXIT AND PAPER INVERSION....................................... 2-99

Paper Exit Mechanism....................................................................... 2-99

Junction Gate Mechanism.................................................................. 2-99

Paper Exit Cover................................................................................2-99

2.10 DUPLEX TRAY................................................................................... 2-100

2.10.1 OVERVIEW ............................................................................... 2-100

2.10.2 DRIVE MECHANISM................................................................. 2-101

2.10.3 PAPER FEED INTO THE DUPLEX TRAY................................. 2-102

Duplex Stacking............................................................................... 2-102

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Paper Feed from the Duplex Tray.................................................... 2-102

Duplex Entrance to Duplex Tray...................................................... 2-103

2.10.4 JOGGER MECHANISM............................................................. 2-104

2.10.5 PAPER FEED FROM THE DUPLEX TRAY............................... 2-105

Bottom Plate Lift Mechanism ........................................................... 2-105

2.10.6 PAPER FEED-OUT MECHANISM............................................. 2-106

2.11 SYSTEM CONFIGURATION.............................................................. 2-107

2.11.1 CONFIGURATION..................................................................... 2-107

2.11.2 NORMAL COPY MODE............................................................. 2-108

Main Power Switch Off State ........................................................... 2-108

Power-off (Sleep) State.................................................................... 2-108

Copier Modes................................................................................... 2-109

2.11.3 OPERATION PANEL................................................................. 2-110

2.11.4 PRINTER CONTROLLER INTERFACE .................................... 2-111

3. INSTALLATION PROCEDURES................................................. 3-1

3.1 INSTALLATION REQUIREMENTS .......................................................... 3-1

3.1.1 DIMENSIONS.................................................................................. 3-1

3.1.2 ENVIRONMENT ..............................................................................3-2

Environmental Requirements............................................................... 3-2

Minimum Space Requirements............................................................ 3-3

Power Requirements............................................................................ 3-4

3.2 COPIER.................................................................................................... 3-5

3.2.1 ACCESSORY CHECK..................................................................... 3-5

3.2.2 PREPERATION............................................................................... 3-6

3.2.3 DEVELOPER INSTALLATION....................................................... 3-10

3.2.4 LOADING TONER CARTRIDGES................................................. 3-14

3.2.5 FUSING UNIT................................................................................ 3-16

3.2.6 DEFAULT SETTINGS AND OPERATION CHECKS..................... 3-17

3.2.7 HEIGHT ADJUSTMENT................................................................ 3-19

3.2.8 COUNTER DISPLAY SETTING...................................................... 3-19

3.2.9 RESETTING THE ELECTRONIC TOTAL COUNTER................... 3-19

3.2.10 PREPARATION FOR TRANSPORT............................................ 3-20

3.3 PLATEN COVER (A749-01)................................................................... 3-21

3.3.1 INSTALLATION............................................................................. 3-21

3.4 ARDF (A663).......................................................................................... 3-22

3.4.1 ACCESSORY CHECK................................................................... 3-22

3.4.2 INSTALLATION............................................................................. 3-23

3.5 SORTER STAPLER (A831).................................................................... 3-24

3.5.1 INSTALLATION............................................................................. 3-24

3.6 LCT (A683)............................................................................................. 3-29

3.6.1 INSTALLATION............................................................................. 3-29

3.7 LCT ADAPTER (A840)........................................................................... 3-30

3.7.1 INSTALLATION............................................................................. 3-30

3.8 FILM PROJECTOR TABLE (A702-19)................................................... 3-36

3.8.1 INSTALLATION............................................................................. 3-36

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3.9 FILM PROJECTOR UNIT(A846) ............................................................ 3-38

3.9.1 ACCESSORY CHECK................................................................... 3-38

3.9.2 INSTALLATION............................................................................. 3-39

3.10 KEY COUNTER HOLDER.................................................................... 3-46

3.11 USER CODE SETTING........................................................................ 3-47

4. SERVICE TABLES......................................................................4-1

4.1 SERVICE PROGRAM (SP) MODES........................................................ 4-1

4.1.1 HOW TO ENTER AN SP MODE...................................................... 4-1

4.1.2 SP MODE TYPES............................................................................ 4-3

4.1.3 SP MODE CHART........................................................................... 4-3

4.1.4 SP4-301 APS OPERATION CHECK DETAILS ............................... 4-3

4.1.5 TEST PATTERN.............................................................................. 4-5

4.1.6 SP5-803 INPUT CHECK.................................................................. 4-6

4.1.7 SP5-804 OUTPUT CHECK.............................................................. 4-9

4.1.8 SP5-955 PRINTER INTERNAL PATTERN .................................... 4-11

5-955-018: Internal Pattern Types...................................................... 4-11

4.2 USER TOOLS......................................................................................... 4-11

4.2.1 HOW TO ENTER USER TOOLS................................................... 4-11

4.2.2 DETAILED DESCRIPTION OF USER TOOLS.............................. 4-12

4.3 TP/SW/LED/FUSE.................................................................................. 4-12

4.3.1 MAIN CONTROL BOARD TEST PINS.......................................... 4-12

4.3.2 LD MAIN CONTROL BOARD TEST PINS..................................... 4-13

4.3.3 I/O CONTROL BOARD TEST PINS.............................................. 4-13

4.3.4 FUSE SPECIFICATIONS .............................................................. 4-19

4.3.5 LED/SW SPECIFICATIONS OF SCANNER IPU BOARD............. 4-20

LED Specifications............................................................................. 4-20

SW Specifications.............................................................................. 4-20

5. PREVENTIVE MAINTENANCE...................................................5-1

5.1 PM PROCEDURES.................................................................................. 5-1

5.1.1 PM-RELATED COUNTERS............................................................. 5-1

SP7-803 (PM Counter Display)............................................................ 5-1

5.1.2 REGULAR PREVENTIVE MAINTENANCE FLOW DIAGRAM........ 5-4

5.2 REGULAR PM ITEMS.............................................................................. 5-7

5.2.1 REGULAR PM TABLE..................................................................... 5-7

Peripherals......................................................................................... 5-11

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6. REPLACEMENT AND ADJUSTMENT ........................................ 6-1

6.1 PM-RELATED COUNTERS...................................................................... 6-1

6.2 SERVICE REMARKS............................................................................... 6-1

6.3 COVERS AND FILTERS.......................................................................... 6-2

6.3.1 UPPER AND LOWER FRONT COVER........................................... 6-2

6.3.2 RIGHT-SIDE FRONT COVER AND RIGHT EDGE COVER............ 6-2

6.3.3 INNER COVERS.............................................................................. 6-3

6.3.4 REAR COVERS............................................................................... 6-3

6.3.5 LEFT COVERS................................................................................ 6-4

6.3.6 EXPOSURE GLASS........................................................................ 6-4

6.3.7 OPERATION PANEL....................................................................... 6-5

6.3.8 USED TONER TANK....................................................................... 6-5

6.3.9 CHARGE CORONA FILTER............................................................ 6-6

6.3.10 DUST AND OZONE FILTERS....................................................... 6-6

6.3.11 SCANNER FILTER........................................................................ 6-7

6.3.12 REVOLVER FILTER...................................................................... 6-7

6.3.13 INNER COVER FILTER................................................................. 6-8

6.3.14 FUSING UNIT FILTER................................................................... 6-8

6.4 UNIT REMOVAL....................................................................................... 6-9

6.4.1 REVOLVER/DRUM DRAWER......................................................... 6-9

6.4.2 DRUM UNIT REMOVAL................................................................ 6-10

6.4.3 REINSTALLING THE REVOLVER/DRUM DRAWER.................... 6-11

6.4.4 IMAGE TRANSFER BELT UNIT REMOVAL................................. 6-12

Reinstalling the Image Transfer Belt Unit........................................... 6-13

6.4.5 PAPER TRANSFER UNIT REMOVAL........................................... 6-14

6.4.6 REMOVING THE FUSING UNIT................................................... 6-15

6.5 DRUM UNIT............................................................................................ 6-16

6.5.1 DRUM REPLACEMENT................................................................ 6-16

Post-replacement Procedure ............................................................. 6-17

6.5.2 CLEANING BLADE REPLACEMENT............................................ 6-18

6.5.3 CLEANING BRUSH REPLACEMENT........................................... 6-19

6.5.4 LUBRICANT BAR REPLACEMENT.............................................. 6-19

6.5.5 BIAS ROLLER BLADE REPLACEMENT....................................... 6-20

6.5.6 CHARGE GRID AND CORONA WIRE REPLACEMENT.............. 6-20

6.5.7 PCC REPLACEMENT ................................................................... 6-21

6.5.8 DRUM POTENTIAL SENSOR REPLACEMENT........................... 6-22

6.5.9 ID SENSOR REPLACEMENT....................................................... 6-23

6.6 SCANNER UNIT..................................................................................... 6-24

6.6.1 EXPOSURE LAMP REPLACEMENT............................................ 6-24

6.6.2 SBU REPLACEMENT.................................................................... 6-25

6.6.3 OPENING THE SCANNER UNIT.................................................. 6-26

6.6.4 SCANNER IPU MAIN/SUB BOARD REPLACEMENT................... 6-28

6.6.5 SCANNER WIRE REPLACEMENT............................................... 6-29

6.6.6 APS AND H.P. SENSOR REPLACEMENT ................................... 6-32

6.7 COPY IMAGE ADJUSTMENT................................................................ 6-33

6.7.1 PRINTER γ ADJUSTMENT............................................................ 6-33

Auto Color Calibration (ACC)............................................................. 6-33

KCMY Color Balance Adjustment...................................................... 6-33

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ACC Target Modification.................................................................... 6-36

6.7.2 MAIN SCAN POSITION DOT CORRECTION............................... 6-37

6.8 LASER OPTICS SECTION..................................................................... 6-40

6.8.1 POLYGON MIRROR MOTOR REPLACEMENT............................ 6-40

6.8.2 LASER SYNCHRONIZING DETECTOR REPLACEMENT............ 6-42

6.8.3 LD UNIT REPLACEMENT............................................................. 6-42

LD Pitch Check and Adjustment]........................................................ 6-43

6.8.4 SQUARENESS ADJUSTMENT..................................................... 6-47

6.8.5 LD CONTROL BOARD REPLACEMENT...................................... 6-49

6.9 DEVELOPMENT UNIT........................................................................... 6-50

6.9.1 DEVELOPER REPLACEMENT..................................................... 6-50

Developer Collection.......................................................................... 6-50

6.9.2 DEVELOPER INSTALLATION....................................................... 6-53

6.9.3 DEVELOPMENT UNIT REPLACEMENT....................................... 6-58

6.9.4 TONER CATCH COVER CLEANING............................................ 6-59

6.9.5 REVOLVER MOTOR REPLACEMENT......................................... 6-60

6.9.6 TONER DENSITY SENSOR REPLACEMENT.............................. 6-61

6.9.7 TD SENSOR NONCONTACT COUPLER REPLACEMENT.......... 6-62

Main Unit Element.............................................................................. 6-62

TD Sensor Interface (I/F) Board......................................................... 6-63

6.8 IMAGE TRANSFER SECTION............................................................... 6-65

6.8.1 IMAGE TRANSFER BELT REPLACEMENT ................................. 6-65

6.8.2 IMAGE TRANSFER BELT BLADE REPLACEMENT..................... 6-67

6.8.3 TRANSFER BELT LUBRICANT BAR AND LUBRICANT

BRUSH REPLACEMENT .............................................................. 6-68

6.8.4 PAPER TRANSFER BELT REPLACEMENT ................................. 6-69

6.8.5 PAPER TRANSFER BELT BLADE/CLEANING BRUSH

REPLACEMENT............................................................................ 6-69

6.8.6 BACK BRUSH REPLACEMENT.................................................... 6-70

6.8.7 PAPER TRANSFER BELT DISCHARGE CORONA WIRE

REPLACEMENT............................................................................ 6-70

6.8.8 PAPER DISCHARGE CORONA WIRE REPLACEMENT.............. 6-71

6.9 PAPER FEED AND REGISTRATION SECTION.................................... 6-72

6.9.1 BY-PASS FEED TABLE REMOVAL.............................................. 6-72

6.9.2 BY-PASS FEED PAPER WIDTH SENSOR REPLACEMENT....... 6-73

6.9.3 BY-PASS PICK-UP ROLLER REPLACEMENT............................. 6-74

6.9.4 BY-PASS FEED ROLLER REPLACEMENT.................................. 6-74

6.9.5 BY-PASS SEPARATION ROLLER REPLACEMENT.................... 6-75

6.9.6 BY-PASS PAPER FEED UNIT REMOVAL.................................... 6-75

6.9.7 BY-PASS PAPER FEED UNIT INSTALLATION............................ 6-76

6.9.8 REGISTRATION SENSOR REPLACEMENT................................ 6-78

6.9.9 PAPER TRAY ROLLER REPLACEMENT..................................... 6-78

6.9.10 PAPER FEED UNIT AND PAPER FEED CLUTCH

REPLACEMENT.......................................................................... 6-79

6.9.11 COPY IMAGE AREA ADJUSTMENT .......................................... 6-80

PAPER TRANSPORT, FUSING, AND PAPER EXIT......................... 6-83

6.10.1 TRANSPORT UNIT REMOVAL................................................... 6-83

6.10.2 FUSING UNIT TOP COVER REMOVAL ..................................... 6-83

6.10.3 OIL SUPPLY UNIT REPLACEMENT AND CLEANING............... 6-84

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6.10.4 HOT ROLLER BLADE REPLACEMENT ..................................... 6-85

6.10.5 CLEANING THE CLEANING ROLLER SCRAPER...................... 6-86

6.10.6 FUSING THERMOFUSE AND THERMISTOR REPLACEMENT 6-86

6.10.7 FUSING UNIT DISASSEMBLY.................................................... 6-87

6.10.8 FUSING LAMP REPLACEMENT................................................. 6-88

6.10.9 HOT ROLLER REPLACEMENT.................................................. 6-88

6.10.10 HOT ROLLER CLEANING ROLLER CLEANING...................... 6-89

6.10.11 PRESSURE ROLLER LAMP/ROLLER REPLACEMENT.......... 6-89

6.10.12 PRESSURE THERMOFUSE AND THERMISTOR

REPLACEMENT........................................................................ 6-90

6.10.13 PRESSURE CLEANING ROLLER CLEANING......................... 6-90

6.10.14 NIP BAND WIDTH ADJUSTMENT............................................ 6-91

6.10.15 CAUTIONS TO BE TAKEN WHEN USING A FUSING UNIT

THAT HAS BEEN IN STOCK FOR A LONG PERIOD .............. 6-92

6.11 DUPLEX UNIT...................................................................................... 6-93

6.11.1 DUPLEX UNIT REMOVAL........................................................... 6-93

6.11.2 SEPARATION ROLLER REPLACEMENT................................... 6-93

6.11.3 FEED ROLLER REPLACEMENT................................................ 6-94

6.11.4 DUPLEX FEED MOTOR REPLACEMENT.................................. 6-95

6.12 SYSTEM AND ELECTRONICS............................................................ 6-97

6.12.1 SOFTWARE UPDATE USING AN IC CARD............................... 6-97

Care of the IC Card............................................................................ 6-97

Upgrading the Main Control Board Software...................................... 6-97

Upgrading the Scanner IPU Software................................................ 6-98

NV-RAM Uploading and Downloading............................................. 6-101

Upload/download procedure............................................................ 6-101

6.12.2 RAM CLEAR.............................................................................. 6-102

RAM Clear Procedure...................................................................... 6-102

6.12.3 MAIN CONTROL BOARD.......................................................... 6-103

Main Control Board Replacement Procedure................................... 6-103

6.12.4 COUNTERS............................................................................... 6-104

About the Total Counter................................................................... 6-104

Mechanical Counter......................................................................... 6-104

NV-RAM Replacement Procedure................................................... 6-105

6.12.5 TOUCH PANEL CALIBRATION................................................. 6-106

7. TROUBLESHOOTING.................................................................7-1

7.1 PROCESS CONTROL ERROR CONDITIONS ........................................ 7-1

7.1.1 PROCESS CONTROL SELF CHECK RESULTS (SP3-975-00)...... 7-1

7.1.2 DEVELOPER SETUP RESULTS (SP3-964-00).............................. 7-2

“Developer Agitation (SP2-225)” OPERATION FLOW........................ 7-3

7.1.3 TD SENSOR INITIALIZATION RESULTS (SP3-005-006)............... 7-3

7.1.4 SELF-CHECK PROCESS CONTROL RELATED SCS ................... 7-4

SC385: Vsg Adjustment Error.............................................................. 7-4

7.2 SC CODE TABLE..................................................................................... 7-4

7.3 DRUM LIGHT FATIGUE............................................................................ 7-5

Page 13

OPTIONS

ARDF (A663)

1. SPECIFICATIONS.................................................................A663-1

2. COMPONENT LAYOUT........................................................A663-2

2.1 MECHANICAL COMPONENTS..........................................................A663-2

2.2 ELECTRICAL COMPONENTS...........................................................A663-3

3. ELECTRICAL COMPONENT DESCRIPTION.......................A663-4

4. DETAILED DESCRIPTIONS.................................................A663-5

4.1 ORIGINAL PICK-UP MECHANISM....................................................A663-5

4.2 SEPARATION AND PAPER FEED MECHANISM..............................A663-6

4.3 FRICTION BELT DRIVE MECHANISM..............................................A663-7

4.4 ORIGINAL SIZE DETECTION............................................................A663-8

4.5 PAPER TRANSPORT MECHANISM..................................................A663-9

4.6 THICK/THIN ORIGINAL MODES ..................................................... A663-10

4.7 ORIGINAL FEED-OUT MECHANISM...............................................A663-11

4.8 TWO-SIDED ORIGINAL FEED MECHANISM..................................A663-12

5. TIMING CHARTS ................................................................A663-13

5.1 A4 SIDEWAYS: 1 SIDED ORIGINAL ...............................................A663-13

5.2 COMBINE 2 ORIGINAL MODE........................................................A663-14

5.3 A4 SIDEWAYS: DUPLEX.................................................................A663-15

6. SERVICE TABLES..............................................................A663-16

6.1 DIP SWITCHES................................................................................A663-16

6.2 VARIABLE RESISTORS...................................................................A663-17

6.3 LED...................................................................................................A663-17

6.4 FUSE................................................................................................A663-17

7. REPLACEMENT AND ADJUSTMENT................................A663-18

7.1 TRANSPORT BELT REPLACEMENT..............................................A663-18

7.2 FEED ROLLER REPLACEMENT..................................................... A663-19

7.3 FRICTION BELT REPLACEMENT...................................................A663-20

7.4 ORIGINAL SET AND WIDTH SENSOR REPLACEMENT................A663-21

7.5 VERTICAL REGISTRATION ADJUSTMENT...................................A663-22

7.5.1 ONE SIDED THIN ORIGINAL MODE......................................A663-22

7.5.2 TWO SIDED ORIGINAL MODE...............................................A663-23

7.6 SIDE-TO-SIDE REGISTRATION (DF POSITIONING)

ADJUSTMENT..................................................................................A663-24

Page 14

LCT (A683)

1. OVERALL MACH IN E INF O RMATION..................................A683-1

1.1 SPECIFICATIONS..............................................................................A683-1

1.2 MECHANICAL COMPONENT LAYOUT.............................................A683-2

1.3 ELECTRICAL COMPONENT LAYOUT..............................................A683-3

1.4 ELECTRICAL COMPONENT DESCRIPTION....................................A683-4

1.5 DRIVE LAYOUT .................................................................................A683-5

2. DETAILED DESCRIPTIONS.................................................A683-6

2.1 PAPER FEED MECHANISM..............................................................A683-6

2.2 TRAY LIFT AND PAPER HEIGHT DETECTION MECHANISM.........A683-7

Tray lifting conditions ..................................................................... A683-7

Tray lowering conditions ................................................................A683-7

2.3 TRAY UNIT SLIDE MECHANISM.......................................................A683-8

3. SERVICE TABLES................................................................A683-9

3.1 DIP SWITCHES..................................................................................A683-9

3.2 TEST POINTS....................................................................................A683-9

3.3 SWITCHES.........................................................................................A683-9

3.4 FUSES................................................................................................ A683-9

4. REPLACEMENT AND ADJUSTMENT................................A683-10

4.1 COVER REPLACEMENT.................................................................A683-10

Tray Cover...................................................................................A683-10

Front Cover..................................................................................A683-10

Rear Cover...................................................................................A683-10

Right Lower Cover .......................................................................A683-10

Upper Cover.................................................................................A683-10

4.2 ROLLER REPLACEMENT................................................................A683-11

4.2.1 PAPER FEED, SEPARATION, AND PICK-UP ROLLERS ......A683-11

Pick-up Roller...............................................................................A683-11

Paper Feed Roller........................................................................A683-11

Separation Roller.........................................................................A683-11

4.3 TRAY LIFT AND PAPER END SENSOR REPLACEMENT .............. A683-12

Tray Lift Sensor............................................................................A683-12

Paper End Sensor........................................................................ A683-12

4.4 RELAY SENSOR REPLACEMENT..................................................A683-13

4.5 SIDE FENCE POSITION CHANGE..................................................A683-14

SORTER STAPLER (A831)

1. OVERALL MAHC INE INFORMATION..................................A831-1

1.1 SPECIFICATIONS..............................................................................A831-1

1.2 COMPONENT LAYOUT.....................................................................A831-3

1.2.1 MECHANICAL COMPONENT LAYOUT .................................... A831-3

1.2.2 DRIVE LAYOUT.........................................................................A831-4

Page 15

2. DETAILED DESCRIPTION.................................................... A831-5

2.1 BASIC OPERATION...........................................................................A831-5

2.1.1 NORMAL (PROOF MODE) AND SORT/STACK MODE............A831-5

Normal (Proof) Mod e (From the Turn Gate Section

to the Proof Tray) ...............................................................A831-5

Sort Mode (From the Turn Gate Section to the Bins).....................A831-6

Stack Mode (From the Turn Gate Section to the Bins)...................A831-7

Reverse Mode (From the Turn Gate Section to the Bins)..............A831-8

2.1.2 STAPLE MODE.........................................................................A831-9

2.2 TURN GATE SECTION....................................................................A831-11

2.3 BIN DRIVE MECHANISM.................................................................A831-12

2.4 BIN HOME POSITION......................................................................A831-13

2.5 JOGGER SECTION..........................................................................A831-14

2.6 BIN REAR PLATE DRIVE SECTION................................................ A831-15

2.7 GRIP ASSEMBLY.............................................................................A831-16

2.7.1 GRIP MOTOR..........................................................................A831-17

2.7.2 GRIP SHIFT MOTOR ..............................................................A831-18

2.8 STAPLE UNIT...................................................................................A831-19

2.8.1 STAPLE UNIT DRIVE MECHANISM.......................................A831-19

2.8.2 STAPLER ................................................................................A831-20

Staple Prohibit Conditions............................................................ A831-21

2.8.3 STAPLE UNIT PULLED-OUT MECHANISM...........................A831-22

3. REPLACEMENTS AND ADJUSTMENTS...........................A831-23

3.1 EXTERIOR COVER REMOVAL....................................................... A831-23

3.2 STAPLER REMOVAL AND REINSTALLATION...............................A831-24

3.3 JOGGER PLATE REMOVAL AND INSTALLATIOIN........................A831-25

Removal.......................................................................................A831-25

Installation....................................................................................A831-25

3.4 BINS REMOVAL...............................................................................A831-26

Removal.......................................................................................A831-26

Installation....................................................................................A831-28

3.5 MAIN MOTOR REMOVAL................................................................A831-30

3.6 GRIP ASSEMBLY REMOVAL..........................................................A831-31

3.7 UPPER GRIP ASSEMBLY REMOVAL ............................................. A831-32

3.8 GRIP SHIFT MOTOR REMOVAL.....................................................A831-33

3.9 HELICAL WHEELS REMOVAL........................................................A831-34

Removal.......................................................................................A831-34

Front Helical Wheel......................................................................A831-34

Rear Helical Wheel ...................................................................... A831-35

Installation....................................................................................A831-36

Rear Helical Wheel ...................................................................... A831-36

Front Helical Wheel......................................................................A831-37

Alignment of the 2 Helical Wheels................................................A831-38

3.10 GRIP MOTOR AND SENSORS REMOVAL...................................A831-39

3.10.1 GRIP MOTOR/GRIP MOTOR HP SENSOR/GRIP

SHIFT MOTOR HP SENSOR REMOVAL............................. A831-39

3.11 MAIN CONTROL BOARD REPLACEMENT...................................A831-40

xii

Page 16

4. SP MODE AND STAPLE POSITION ADJUSTMENT..........A831-41

4.1 SERVICE TABLES (MAIN CONTROL BOARD)...............................A831-41

4.1.1 DIP SWITCHES.......................................................................A831-41

DIP 1 (Mode) SP Mode................................................................A831-41

DIP 2 (Staple) Staple Position Adjustment (A) DIP 3 (Chuck)

Staple Position Adjustment (B).................................................A831-41

FPU (A846)

1. SPECIFICAT IONS..................................................................

A846-

2. ELECTRICAL COMPONENT LAYOUT

AND DESCRIPTIONS...........................................................

3. SECTIONAL DESCRIPTIONS................................................

3.1 OVERVIEW ........................................................................................ A846-3

3.2 SHADING ...........................................................................................A846-4

3.3 MIRROR UNIT....................................................................................A846-5

A846A846-

APPENDIX

APPENDIX-1

SC CODE TABLE

APPENDIX-2

SP MODE

APPENDIX-3

POP-UP DISPALYS

APPENDIX-4

TIMING CHARTS

2 3

xiii

Page 17

30 March 1999 SPECIFICATIONS

1. OVERALL MACHINE INFORMATION

1.1 SPECIFICATIONS

1.1.1 MAJOR UNITS

•

A257 copier: Basic model

•

A269 copier: Editing model

Overall

Information

1. Original tray (A430)

2. FPU (A846)

3. FPU table (A702-19)

4. LCT (A683) + LCT adapter (A840-01)

5. 20 bin sorter stapler (A831)

6. ARDF (A663)

A269V001.PCX

Other options

•

Platen cover (A749-01)

•

Controller interface (A839)

1-1

Page 18

SPECIFICATIONS 30 March 1999

1.1.2 BASIC SPECIFICATIONS

Type: Console type Copy process: Dry electrostatic transfer system Number of scans: 1 (image memory for A3/DLT full color copy is

installed) Pre-scan: Only when Auto Original Type mode is used Resolution: Copy mode (read/write): 400 dpi/600 dpi

Print mode (write): 600 dpi Gradations: 256 gradations (8 bits) Original types: Sheet, book, object Maximum original size: A3/11" x 17" Original reference position: Left rear corner Maximum print size: 323 mm x 473 mm Copy paper size: First tray

Maximum: A4 (S/L)/8 Minimum: A5 (S)/ 8

Other trays

Maximum: A3/11" x 17" Minimum: A5 (S)/ 8

By-pass

Maximum: 13" x 19" (330 x 483 mm) Minimum: Postcard (100 x 148 mm)

Auto/duplex

Maximum: A3/11" x 17" Minimum: A5 (S)/ 8

" x 11" (S/L)

1/2

" x 5

1/2

" x 5

1/2

" x 5

1/2

" (S)

Paper thickness: Tray feed (including duplex):

64 to 105 g/m2, 17 to 28 lb

By-pass feed:

64 to 256 g/m2, 17 to 68 lb Thick paper 1 (105 ~ 157 g/m2, 28 ~ 42 lb) Thick paper 2 (157 ~ 256 g/m2, 42 ~ 68 lb)

Non-reproduction area:

Leading edge: 4±2 mm Left and right: 2±2 mm (4 mm or less in total) Trailing edge: 2±2 mm

1-2

Page 19

30 March 1999 SPECIFICATIONS

Copying speed (cpm):

Normal paper/

normal mode

OHP/thick

paper

ARDF 1 to 1

Duplex feed

Full

color

A4/8

" x 11" or less 10 40 13.5 10 13.5 10

1/2

A3/11" x 17" 5207575

" x 11" or less 4.5 7 5 4.5 5 4.5

1/2

A3/11" x 17" 2 3.5 2.5 2 2.5 2

" x 11" or less8318888

1/2

A3/11" x 17" 5155554

" x 11" or less 10 35 13.5 10 13.5 10

1/2

A3/11" x 17"T 5207575

C/M/

Y/K

B, G R

Warm-up time: 8 minutes and 30 seconds or less First copy time (A4/8

" x 11") Normal Paper:

1/2

Full color: 16.5 seconds or less

K, C, M, Y: 8 seconds or less

B, G: 14 seconds or less

R: 16.5 seconds or less Thick paper/OHP:

Full color: 29 seconds or less

Paper feed capacity: Tray:

500-sheet paper tray: 3 trays By-pass feed:

50 sheets Duplex tray:

50-sheet s (30 sheets for A3/11" x 17"

20 sheets (Full color)

K+M

K+Y

K+C

Overall

Information

Paper feed system: Tray:

FRR system (Stack height: 53 mm max.) By-pass feed:

FRR system (Stack height: 6 mm max.) Duplex tray:

Friction roller separation system

Reproduction Ratios:

" x 11"LT/11" x 17"DLT version A4/A3 version

1/2

Enlargement Full size Reduction Programmable Zoom

121, 129, 155, 200, 400% 115, 122, 141, 200, 400%

100% 100%

25, 50, 65, 73, 78, 85, 93% 25, 50, 65, 71, 75, 82, 93%

2 user ratios 2 user ratios

25% to 400% in 1% steps 25% to 400% in 1% steps

1-3

Page 20

SPECIFICATIONS 30 March 1999

Number of continuous copies: 1 to 999 sheets Scanning system: 3-line 1-chip CCD sensor (400 dpi/5,000 pixels) Light source: 1-halogen-lamp indirect lighting (frosted surface) Print system: Twin laser beam, 600 dpi Development system: 2-component magnetic brush Drum cleaning system: Counter blade Image Transfer system: Belt transfer system Fusing system: Heat and pressure roller system with oil application Dimensions:

A269V155.WMF

A269V156.WMF

1. Copier

730 mm (W1) x 780 mm (D) x 980 mm (H1)

2. Copier + Platen Cover + Paper Exit Tray + By-pass Tray

1,643 mm (W2) x 780 mm (D) x 1,045 mm (H2)

1-4

Page 21

30 March 1999 SPECIFICATIONS

A269V158.WMF

3. Copier + ARDF + LCT + Sorter Stapler + By-pass Tray

1,930 mm (W3) x 780 mm (D) x 1,110 mm (H3)

Overall

Information

Weight: 240 kg Power source: 120 V, 60 Hz, 16 A (North America)

220 ~ 240 V, 50 Hz, 8 A (Europe, Mid-East) 220 ~ 240 V, 50/60 Hz, 8 A (Asia)

1-5

Page 22

SPECIFICATIONS 30 March 1999

1.1.3 PLATEN/ARDF ORIGINAL SIZE DETECTION

Size (width x length)

[mm]

A3 (297 x 420) L No Yes No Yes B4 (257 x 364) L No Yes No Yes A4 (210 x 297) L No Yes Yes Yes A4 (297 x 210) S No Yes Yes Yes B5 (182 x 257) L No Yes No Yes B5 (257 x 182) S No Yes No Yes A5 (148 x 210) L No Yes No Yes A5 (210 x 148) S No Yes No Yes B6 (128 x 182) L No No No Yes B6 (182 x 128) S No No No Yes 11" x 17" (DLT) Yes No Yes Yes 11" x 15" No No Yes No 10" x 14" Yes No Yes Yes

8.5" x 14" (LG) Yes No Yes No

8.5" x 13" (F4) Yes Yes Yes Yes

8.25" x 13" No No No No 8" x 13"(F) Yes No Yes No

8.5" x 11" (LT) Yes No Yes Yes 11" x 8.5" (LT) Yes No Yes Yes 8" x 10.5" No No No No 8" x 10" Yes No Yes No

5.5" x 8.5" (HLT) Yes No Yes No

8.5" x 5.5" (HLT) Yes No Yes No A6 (105 x 148) L No No No No

Inch Metric Inch Metric

Platen ARDF

NOTE:

In the above table "Inch" refers to versions of the machine that use nonmetric traditional paper sizes and "Metric" refers to versions that use ISO standard paper sizes.

1-6

Page 23

30 March 1999 SPECIFICATIONS

1.1.4 COPY PAPER SIZES

Size (width x length)

[mm]

A3 (297 x 420) L No Yes Yes Yes B4 (257 x 364) L No Yes Yes Yes A4 (210 x 297) L Yes Yes Yes Yes A4 (297 x 210) S Yes Yes Yes Yes B5 (182 x 257) L Yes Yes Yes Yes B5 (257 x 182) S Yes Yes Yes Yes A5 (148 x 210) L No No No Yes A5 (210 x 148) S Yes Yes Yes Yes B6 (128 x 182) L No No No Yes B6 (182 x 128) S No No No Yes 13" x 19" No No No Yes 12" x 18" No No No Yes 11" x 17" (DLT) No Yes Yes Yes 11" x 15" No Yes No No 10" x 14" No Yes Yes No

8.5" x 14" (LG) No Yes Yes No

8.5" x 13" (F4) No Yes Yes No

8.25" x 13" No Yes Yes No 8" x 13"(F) No Yes Yes No

8.5" x 11" (LT) Yes Yes Yes Yes 11" x 8.5" (LT) Yes Yes Yes Yes 8" x 10.5" No Yes Yes No 8" x 10" No Yes Yes No

5.5" x 8.5" (HLT) No No No Yes

8.5" x 5.5" (HLT) Yes Yes Yes Yes A6 (105 x 148) L No No No Yes

1st Tray 2nd/3rd Tray Duplex Tray By-pass Tray

Overall

Information

NOTE:

The by-pass sizes shown above are those that the machine can automatically detect. When by-pass feeding other sizes, the user should select "Custom Size" and input the length and width. (Length limitations = 148 ~ 483 mm, Width limitations = 100 ~ 330 mm).

1-7

Page 24

SPECIFICATIONS 30 March 1999

1.1.5 NOISE EMISSION

Copier Only

Stand-by mode 54 dB (A)

Copy-mode average 70 dB (A)

1.1.6 POWER CONSUMPTION

1. Maximum power consumption

1.75 kVA

2. Average power consumption

Sleep mode 0.015 kW

Stand-by mode 0.6 kW

Warm-up time 1.7 kW

Copying 1.5 kW

1-8

Page 25

30 March 1999 MECHANISM OVERVIEW

1.2 MECHANISM OVERVIEW

1.2.1 IMAGE GENERATION PROCESS

11 10

1 2

Overall

Information

A269V101.WMF

1. Drum charge

The charge corona applies a negative charge to the OPC drum and the grid ensures that this charge is even.

2. Quenching

After cleaning, the OPC is fully exposed to light from an array of red LEDs, quenching the residual charge on the OPC drum in preparation for the next copy cycle.

3. Drum cleaning

The cleaning brush increases drum cleaning efficiency by applying lubricant to the OPC drum. The cleaning blade scrapes the residual toner off the OPC drum.

4. PCC (Pre-cleaning corona)

The PCC discharges the photoconductor drum and applies AC and negative DC discharges to reduce the charge holding the residual toner to the drum, thereby improving the efficiency of cleaning.

1-9

Page 26

MECHANISM OVERVIEW 30 March 1999

5. Image transfer to image transfer belt

Positive charge applied to the back of the image transfer belt transfers the toner image on the OPC drum to the image transfer belt.

6. Image transfer to paper

The negatively charged toner image is transferred to the paper by giving a positive charge to the back of the paper.

7. Image transfer belt cleaning and lubricant application

The brush applies lubricant, which makes it easier for the counter blade to scrape excess toner off the transfer belt. The lubricant improves toner transfer ability and reduces the amount of the partial blanking image.

8. Paper transfer belt cleaning

The paper transfer belt blade and brush always contact the paper transfer belt to clean the belt surface.

9. Paper transfer belt discharging

The belt discharge corona unit removes the charge on the paper transfer belt.

10. Paper Separation

A combination of curvature separation and corona discharge separate the paper from the paper transfer belt. The pick-off plate provides mechanical assistance to the separation process.

11. ID sensor

The ID sensor senses the density of the test patch patterns developed on the OPC drum.

12. Development

The latent image on the drum attracts the negatively charged toner. Toner is preferentially attracted to those places on the drum surface where the laser reduced the negative charge. (The development units for each color are included in the revolver unit.)

13. Drum potential sensor

The electrical potential on the OPC drum is sensed by the drum potential sensor for process control.

14. Laser exposure

The laser beam emitted from the laser assembly is reflected by the polygon mirror and projected onto the drum through the fθ lens, drum mirror, and toner shield glass. The laser output varies in intensity to correspond to the image data, and this forms a latent image.

1-10

Page 27

30 March 1999 MECHANISM OVERVIEW

1.2.2 MAJOR UNITS AND PAPER PATH

3 4

Overall

Information

7 6

1. Scanner

•

400 dpi, 10-bit scanning in both main and sub scan directions

•

3-line CCD with reduction optics

•

Halogen exposure lamp

•

5-phase micro-stepper motor drive

A269V102.WMF

2. Operation panel

•

10.4-inch (640 x 480) color LCD (8 bit) touch-panel

3. Laser exposure unit

•

2 laser diode multi-beam system

•

Optics: 6-sided polygon mirror + 2 fθ lenses + barrel toroidal lens (BTL)

•

Polygon motor (23,622 rpm)

•

600 dpi (8 bit) print density

•

Modulation: power modulation + pulse width modulation

1-11

Page 28

MECHANISM OVERVIEW 30 July, 1999 (Revised)

4. Drum unit

•

Drum unit contains OPC drum, charge corona unit, and cleaning unit.

•

Charge corona unit: Single scorotron charge

•

Quenching lamp: LED

•

Drive: Synchronized with the image transfer belt (timing belt + flywheel)

•

Potential sensor and ID sensor included

•

Cleaning unit: Blade, brush, lubricant, and pre-cleaning corona

5. Image transfer and belt drive

•

Image transfer belt: Full time contact with the drum

•

Image transfer: Bias/roller indirect application

•

Paper transfer: Belt transfer

•

Registration: Synchronization by the belt mark detection sensor

•

Image transfer belt: Driven by the image transfer belt motor

•

Paper transfer belt: Driven by the paper transfer motor

•

Separation: Curvature separation + corona discharge

•

Belt cleaning: Counter blade system

•

Lubrication: Brush roller with lubricant bar

6. Paper feed/transport system

•

Paper feed: 3 front loading 500-sheet trays + by-pass transport

•

Transport: Transport belt + vacuum fan

•

Duplexing: Duplex unit installed

7. Development and toner supply

•

Development: Two-component magnetic brush development

•

Development color switching: Revolver system

•

Image density control: TD sensor + ID sensor + process control

•

Toner supply: Cartridge type

•

Toner supply unit: Front of development units (on the revolver)

8. Fusing and paper exit section

•

Fusing: Silicone rubber roller fusing

•

Oil application method: roller

•

Cleaning: Roller cleaning for hot and pressure rollers (-15, -17, -19)

Roller cleaning for hot and cleaning blade for pressure roller (-22, -26, -27, -29)

•

OHP/thick paper speed selection

1-12

Page 29

30 March 1999 PARTS LAYOUT

1.3 PARTS LAYOUT

1.3.1 MAJOR UNIT LAYOUT DIAGRAM

4321

6 7

10 11

Overall

Information

27 26

1. 1st scanner

2. Sensor board unit (SBU)

3. Drum mirror

4. Toner shield glass

5. 2nd scanner

6. Barrel toroidal lens (BTL)

7. Charge corona unit

8. 2nd fθ lens

9. 1st fθ lens

10. Polygon mirror

11. Drum cleaning unit

12. Pre-cleaning corona (PCC)

13. Image transfer unit

14. Image transfer belt cleaning unit

15. By-pass feed table

12 13 14

16 17

18 19

21 202223

A269V103.WMF

16. Registration rollers

17. 1st paper tray

18. Duplex unit

19. 2nd/3rd paper trays

20. Paper transfer belt unit

21. Paper transfer belt cleaning unit

22. Belt discharge corona unit

23. Transport belt

24. Used toner tank

25. Pressure roller

26. Hot roller

27. Separation corona unit

28. Revolver (development units)

29. OPC drum

1-13

Page 30

DRIVE LAYOUT 30 July, 1999 (Revised)

1.4 DRIVE LAYOUT

1. Fusing transport drive

2. Revolver drive

3. Drum drive

4. Scanner drive

A269V110a.WMF

5. Drum peripheral drive

6. Image transfer belt drive

7. Registration drive

8. Paper feed drive

1-14

Page 31

30 March 1999 AIR FLOW

1.5 AIR FLOW

1.5.1 AIR FLOW SYSTEM 1

Overall

Information

1. Fusing fan (upper)

2. Fusing fan (bottom)

3. ID sensor fan

4. Charge fan

A269V111.WMF

5. Transport fan (rear)

6. Transport fan (front)

7. Development cooling fan

1-15

Page 32

AIR FLOW 30 March 1999

1.5.2 AIR FLOW SYSTEM 2

1. Optics cooling fan (front)

2. Optics cooling fan (rear)

A269V112.WMF

3. IPU cooling fan

4. Exhaust fan

1-16

Page 33

30 March 1999 ELECTRICAL PARTS LAYOUT

1.6 ELECTRICAL PARTS LAYOUT

1.6.1 ELECTRICAL PARTS LAYOUT 1

Overall

Information

33 32 31

5 6 7 8

9 10 11 12 13 14 15 16

17 18

19 20 21 22

A269V104.WMF

1. Choke coil

2. Exposure lamp

3. Platen cover position sensor

4. Original length sensor 2

5. Optics anti-condensation heater

6. Original length sensor 1

7. By-pass paper end sensor

8. By-pass paper length sensor

9. By-pass paper width detection board

10. By-pass feed unit switch

11. By-pass feed clutch

12. Main by-pass pick-up solenoid

13. Registration sensor

14. By-pass table sensor

15. By-pass reverse roller solenoid

16. 1st/Duplex paper feed sensor

17. Vertical transport door switch

18. 2nd/3rd paper feed sensor

19. 1st/2nd/3rd pick-up solenoid

20. 1st/2nd/3rd reverse roller solenoid

21. 1st/2nd/3rd upper limit sensor

22. 1st/2nd/3rd paper end sensor

23. Sub by-pass pick-up solenoid

24. Humidity sensor

25. Mechanical total counter

26. Paper transfer heater

27. Paper tray heaters (option)

28. Toner overflow sensor

29. Main switch

30. Paper exit door switch 2

31. Paper exit door switch 1

32. Front door switch

33. Original width sensor

34. CCD

35. Thermostat

36. Scanner H.P. sensor

1-17

Page 34

ELECTRICAL PARTS LAYOUT 30 March 1999

1.6.2 ELECTRICAL PARTS LAYOUT 2

14 13

1. Paper transfer belt shift clutch

2. Image transfer belt cleaning drive clutch

3. Image transfer belt cleaning shift clutch

4. Image transfer belt cleaning H.P. sensor

5. Development clutch

6. Toner supply clutch

7. 1st tray set switch

8. Duplex turn guide sensor

9. Junction gate solenoid

10. 2nd tray paper size switch

A269V105.WMF

11. 3rd tray paper size switch

12. Circuit breaker

13. 2nd paper height sensor

14. 3rd paper height sensor

15. 1st paper height sensor

16. 3rd feed clutch

17. Paper feed drive clutch

18. 2nd tray feed clutch

19. 1st feed clutch

1-18

Page 35

30 March 1999 ELECTRICAL PARTS LAYOUT

1.6.3 ELECTRICAL PARTS LAYOUT 3

Overall

Information

A269V106.WMF

1. LD control board

2. Scanner motor drive board

3. LD drive board

4. Image detection unit

5. Polygon motor drive board

6. Operation panel board

7. Laser synchronizing detector board

8. Main scanner IPU board

9. Main control board

10. Sub scanner IPU board

11. High voltage supply board C/G/B

12. Revolver motor drive board

13. High voltage supply board Q1

14. High voltage supply board D

15. AC drive board

16. Power supply unit

17. High voltage supply board T1/PCC/BR

18. I/O control board

19. Interface board RDS/LCT

20. TD sensor interface board 1

21. Image transfer belt motor drive board

22. Lamp regulator

1-19

Page 36

ELECTRICAL PARTS LAYOUT 30 March 1999

1.6.4 ELECTRICAL PARTS LAYOUT 4

1. Polygon motor

2. Scanner motor

3. Drum motor

4. IPU cooling fan

5. Development cooling fan

6. Optics cooling fan

7. Fusing fan (upper)

8. Fusing fan (bottom)

9. Fusing motor

A269V107.WMF

10. Exhaust fan

11. Tray lift motor

12. Paper feed motor

13. Registration motor

14. Revolver motor

15. Image transfer belt motor

16. Drum peripheral component motor

17. ID sensor fan

18. Charge fan

1-20

Page 37

30 March 1999 ELECTRICAL PARTS LAYOUT

1.6.5 ELECTRICAL PARTS LAYOUT 5

Overall

Information

1. Toner cartridge set sensor

2. TD sensor

3. TD sensor interface board 2

4. Drum potential sensor/board

5. Quenching lamp

6. Belt mark detection sensor

A269V108.WMF

7. ID sensor

8. Paper separation sensor

9. Wire cleaner motor

10. Toner end sensor

11. Revolver H.P. sensor

1-21

Page 38

ELECTRICAL PARTS LAYOUT 30 March 1999

1.6.6 ELECTRICAL PARTS LAYOUT 6

A269V109.WMF

1. Pressure roller fusing lamp

2. Hot roller fusing lamp

3. Pressure roller thermistor

4. Hot roller thermistor

5. Hot roller thermofuse

6. Paper Exit sensor

7. Pressure roller the rmofuse

8. Paper transfer belt motor

9. Paper transfer belt motor drive board

10. Paper transfer belt unit H.P. sensor

11. Transport fan

12. High voltage supply board T2

13. High voltage supply board Q2

14. Oil end sensor

1-22

Page 39

30 March 1999 ELECTRICAL PARTS LAYOUT

1.6.7 ELECTRICAL PARTS LAYOUT 7

Overall

Information

1. Duplex entrance sensor

2. Duplex turn sensor

3. Duplex paper end sensor

4. Duplex feed motor

5. Duplex side fence H.P. sensor

A269V154.WMF

6. Side fence jogger motor

7. End fence jogger motor

8. Duplex control board

9. Duplex end fence H.P. sensor

1-23

Page 40

ELECTRICAL PARTS DESCRIPTIONS 30 March 1999

1.7 ELECTRICAL PARTS DESCRIPTIONS

Symbol Name Function SENSORS

Platen Cover Position Sensor Detects if the platen cover is opened or

S1 S2 Scanner H.P. Sensor Detects the scanner home position. 1/2 G5-H5 1-36

S3 Original Length Sensor 1 Detects the length of originals. 1/2 H7-H8 1-6 S4 Original Length Sensor 2 Detects the length of small size original. 1/2 G7-G8 1-4 S5 Original Width Sensor Detects the width of originals. 1/2 H7-H8 1-33 S6 Revolver H.P. Sensor Detects the revolver home position. 2/2 A3 5-11

Toner Cartridge Set Sensor

Toner End Sensor

S9 Toner Density Sensor - Y 1/2 B11-C11 5-2 S10 Toner Density Sensor - K 1/2 B11-C11 5-2 S11 Toner Density Sensor - M 1/2 B11-C11 5-2 S12 Toner Density Sensor - C S13 Drum Potential Sensor/Board Detects the drum surface potential. 2/2 A4 5-4

ID Sensor

S14

Humidity Sensor Detects the humidity and temperature to

S15

Belt Mark Detection Sensor Detects the belt mark on the image transfer

S16

Image Transfer Belt Cleaning

S17

H.P. Sensor Paper Transfer Belt Unit H.P.

S18

Sensor By-pass Table Sensor

S19

By-pass Paper Length Sensor

S20

By-pass Paper End Sensor

S21 S22 1st Upper Limit Sensor 2/2 D11 1-21

S23 Not used S24 2nd Upper Limit Sensor 2/2 F11 1-21 S25 3rd Upper Limit Sensor S26 1st Paper Height Sensor 2/2 A10 2-15 S27 Not used S28 2nd Paper Height Sensor 2/2 A10-A11 2-13 S29 3rd Paper Height Sensor S30 1st Paper End Sensor 2/2 D11 1-22 S31 Not used S32 2nd Paper End Sensor 2/2 F11 1-22 S33 3rd Paper End Sensor S34 1st Paper Feed Sensor 2/2 D2 1-16 S35 Duplex Paper Feed Sensor 2/2 D2 1-16 S36 2nd Paper Feed Sensor 2/2 F2 1-18

3rd Paper Feed Sensor

S37

closed.

Detects the presence of the toner cartridges.

Detects the presence of toner in the cartridge.

Detects the toner density in the development unit.

Detects the density of the sensor pattern developed on the drum surface.

calculate absolute humidity. belt for synchronizing the image of each

color. Detects the ITB cleaning unit home position.

Detects the home position. Detects if the by-pass table is opened or

closed. Detects whether or not paper on the by-

pass tray is longer than A4 (Letter). Detects whether or not there is paper on the

by-pass tray. Detects the upper limit (paper feed position).

Detects when the tray is nearly out of paper.

Detects whether or not there is paper in the tray.

1. Detects the paper to control the feed timing of next sheet of paper.

2. Detects paper jams at the paper feed section.

3. When a copy is made, it also controls the stop timing of feed clutch and solenoid.

P-to-P

Location

1/2 H5 1-3

2/2 A3 5-1

2/2 A2-A3 5-10

1/2 B11-C11 5-2

2/2 A3 5-7 2/2 A7 1-24

2/2 G2 5-5

2/2 A4-A5 2-4

2/2 E4 6-10

2/2 A4 1-14

2/2 E2 1-8

2/2 D2 1-7

2/2 G11 1-21

2/2 A11 2-14

2/2 F11-G11 1-22

2/2 F2 1-18

Index

No.

1-24

Page 41

30 March 1999 ELECTRICAL PARTS DESCRIPTIONS

Symbol Name Function

Registration Sensor

S38

Paper Separation Sensor

S39 S40 Paper Exit Sensor Detects paper jams at the exit section. 1/2 A1-B1 6-6

Duplex Turn Guide Sensor

S41

Duplex Entrance Sensor

S42

Duplex Turn Sensor Detects the trailing edge of paper to activate

S43 S44 Duplex Paper End Sensor Detects if there is paper in the duplex unit. 2/2 E10 7-3

Duplex Side Fence H.P.

S45

Sensor Duplex End Fence H.P.

S46

Sensor Oil End Sensor Detects whether or not the oil tank is nearly

S47

Toner Overflow Sensor Detects whether or not the toner collection

S48

SWITCHES

SW1 Main Switch Turns the power to the copier on or off. 1/2 F1 1-29 SW2 Front Door Switch 1 2/2 A6 1-32 SW3 Front Door Switch 2 2/2 A7 1-32 SW4 Front Door Switch 3 SW5 Front Door Switch 4 1/2 G11 1-32 SW6 Front Door Switch 5

SW7

SW8

SW9 1st Tray Set Switch 2/2 A8-A9 2-7 SW10 Not used SW11 2nd Tray Paper Size Switch 2/2 A9 2-10 SW12 3rd Tray Paper Size Switch

SW13

SW14 Paper Exit Door Switch 2 Detects if the exit door is opened or closed. 2/2 A6 1-30

By-pass Feed Unit Switch Detects if the by-pass feed unit is opened or

Vertical Transport Door Switch Detects if the vertical transport door is

Paper Exit Door Switch 1 Detects if the exit door is opened or closed

Detects the leading edge of paper to control start timing of the registration rollers. Also, detects paper jams in the registration area.

Detects whether or not paper properly separates from the paper transfer belt.

Detects paper jams at the turn guide section.

Detects a paper jams at the entrance of the duplex tray.

the jogger motor for jogging.

Detects the side fence home position.

Detects the end fence home position.

empty.

bottle is full.

Cuts the DC power to the I/O control board when the door is opened.

Cuts the DC power to the LD control board when the door is opened.

not.

opened or not. Detects if the paper tray is set or not.

Detects the size of paper in the paper tray.

and cuts the DC power when the exit door is opened.

P-to-P

Location

2/2 A5 1-13

2/2 A3 5-8

2/2 A10 2-8

2/2 E10 7-1 2/2 E10 7-2

2/2 E9 7-5

2/2 E9 7-9

1/2 B1 6-14

2/2 A10 1-28

2/2 A7 1-32

1/2 G11 1-32 2/2 A6 1-10

2/2 E2-F2 1-17

2/2 A9 2-11

2/2 A6 1-31

Index

No.

Overall

Information

PCBs

PCB1 PSU Provides AC and DC power. 1/2 C3-F2 3-16 PCB2 PCB3 Lamp Regulator Provides AC power to the exposure lamp. 1/2 H5 3-22

PCB4 Scanner Motor Drive Board Controls the scanner motor. 1/2 F5-G5 3-2

PCB5

PCB6 Main Scanner IPU Board 1/2 D6-G8 3-8 PCB7 PCB8 Main Control Board Controls the printer sequence. 1/2 B8-D11 3-9

AC Drive Board Provides AC power to fusing lamps and

heaters.

CCD

Sub Scanner IPU Board

Converts the light reflected from the original into analog signals for the three basic colors (RGB).

Converts RGB image signal from the CCD to a CMYK signal data and sends the signal to the LD control board.

1/2 C3-F2 3-15

1/2 D7-D8 1-34

1/2 E6-G9 3-10

1-25

Page 42

ELECTRICAL PARTS DESCRIPTIONS 30 March 1999

Symbol Name Function

I/O Control Board

PCB9

PCB10 LD Control Board Controls laser synchronization. 1/2 F9-F11 3-1 PCB11 LD Drive Board Controls the LD output. 1/2 D10 3-3 PCB12 Polygon Motor Drive Board Controls the polygon mirror motor. 1/2 G11 3-5

PCB13 PCB14 IDU (Image Detection Unit) Analyzes images for anti-counterfeiting. 1/2 G8 3-4 PCB15 PCB16 TD Sensor Interface Board 1 1/2 B11 3-20 PCB17 PCB18 Revolver Motor Drive Board Controls the revolver motor. 2/2 D3-E3 3-12 PCB19

PCB20

PCB21

PCB22 PCB23 High Voltage Supply Board Q1 Provides power to the lubricant brush. 2/2 E6-E7 3-13 PCB24

PCB25 PCB26 Operation Panel Board Used to operate the copier. 1/2 C11-D11 3-6

PCB27

PCB28 PCB29 Duplex Control Board Controls the duplex unit. 2/2 D8-E10 7-9

Laser Synchronizing Detector Board

High Voltage Supply Board C/G/B

TD Sensor Interface Board 2

Image Transfer Belt Motor Drive Board

High Voltage Supply Board T1/PCC/BR

Paper Transfer Belt Motor Drive Board

High Voltage Supply Board T2 Provides power to the paper transfer belt

High Voltage Supply Board Q2

High Voltage Supply Board D

Interface Board RDS/LCT Interfaces the sensors, clutches, solenoids,

By-pass Paper Width Detection Board

Interfaces the sensors, clutches, solenoids, and motors in the printer module with the main control board.

Detects the laser beam to control the start timing of main scan writing.

Provides power to the charge corona unit and development rollers.

Provides power to the TD sensors and transmits the output data from the sensors to the main control board.

Controls the image transfer belt motor. Provides power to the image transfer belt

bias roller, PCC unit, and drum cleaning bias roller.

Controls the paper transfer belt motor.

bias roller.

Provides power to the paper transfer belt discharge corona unit.

Provides power to the paper separation corona unit.

and motors in the LCT with the main control board.

Detects the width of paper.

P-to-P

Location

1/2

A2-A11

2/2

C11-H1

1/2 G11 3-7

2/2 B1-B2 3-11

1/2 B11 5-3

2/2 F1-G2 3-21

2/2 B1 3-17

2/2 D5-E5 6-9

2/2 E4 6-12

2/2 E4 6-13

2/2 A9-A10 3-14

1/2 B6-C7 3-17

2/2 E2 1-9

Index

No.

3-18

MOTORS

M1 Polygon Motor Drives the polygon mirror. 1/2 G11 4-1 M2 Wire Cleaner Motor Drives the charge wire cleaner. 2/2 A4 5-9 M3 Drum Motor Drives the drum. 2/2 D5-E6 4-3

Drum peripheral component

Motor

M5 Image Transfer Belt Motor Drives the image transfer belt. 2/2 F2 4-15 M6 Paper Transfer Belt Motor Drives the paper transfer belt. 2/2 E5 6-8 M7 1st Tray Lift Motor 2/2 D10-D11 4-11 M8 Not used M9 2nd Tray Lift Motor 2/2 F10-F11 4-11

M10 3rd Tray Lift Motor

M11

M12

STM1 Scanner Motor Drives the scanner. 1/2 G4 4-2 STM2 Revolver Motor Drives the revolver unit. 2/2 E3 4-14 STM3 Registration Motor Drives the registration roller. 2/2 A6 4-13

Paper Feed Motor

Fusing Motor

Drives the drum cleaning unit, toner supply unit, development unit, and image transfer belt cleaning unit.

Lifts the tray bottom plate up.

Drives the paper feed mechanism for all trays.

Drives the paper transport belts and fusing rollers.

2/2 H2 4-16

2/2 G10-G11 4-11 2/2 A8 4-12

2/2 A11 4-9

1-26

Page 43

30 March 1999 ELECTRICAL PARTS DESCRIPTIONS

Symbol Name Function

STM4

STM5

STM6

CLUTCHES

CL10

CL11

Duplex Feed Motor Side Fence Jogger Motor

(Duplex) End Fence Jogger Motor

(Duplex)

Toner Supply Clutch Transmits the drive to the toner supply

CL1

Development Clutch Transmits the drive to the development

CL2

Image Transfer Belt Cleaning

CL3

Drive Clutch Image Transfer Belt Cleaning

CL4

Shift Clutch

Paper transfer Belt Shift Clutch Shifts/releases the paper transfer belt

CL5 CL6 1st Feed Clutch 2/2 D10-D11 2-19

CL7 Not used CL8 2nd Feed Clutch 2/2 F10-F11 2-18 CL9 3rd Feed Clutch

By-pass Feed Clutch Transmits drive to the by-pass feed

Paper Feed Drive Clutch Transmits drive to the paper feed

Drives the paper feed rollers in the duplex unit.

Drives the duplex side jogger fences.

Drives the duplex end jogger fence.

mechanism.

mechanism. Transmits the drive to the image transfer

belt cleaning unit. Shifts/releases the cleaning brush, cleaning

blade, and entrance seal against/from the image transfer belt.

against/from the image transfer belt. Transmits drive to the paper feed

mechanism.

P-to-P

Location

2/2 E8 7-4

2/2 E9 7-6

2/2 E9 7-7

2/2 A5 2-6

2/2 A5 2-5

2/2 A5 2-2

2/2 A5 2-3

2/2 H2 2-1

2/2 G10-G11 2-16 2/2 E2 1-11

2/2 A8 2-17

Index

No.

Overall

Information

SOLENOIDS

SOL1 1st Pick-up Solenoid 2/2 D10-D11 1-19 SOL2 Not used SOL3 2nd Pick-up Solenoid 2/2 F10-F11 1-19 SOL4 3rd Pick-up Solenoid SOL5 1st Reverse Roller Solenoid 2/2 D10-D11 1-20 SOL6 Not used SOL7 2nd Reverse Roller Solenoid 2/2 F10-F11 1-20 SOL8 3rd Reverse Roller Solenoid

SOL9

SOL10

SOL11

SOL12

FAN MOTORS

FAN1 IPU Cooling Fan Cools the scanner IPU board. 1/2 G5 4-4 FAN2 Optics Cooling Fan (Front) 1/2 G5 4-6 FAN3 Optics Cooling Fan (Rear) FAN4 Charge Fan Provides air flow to the charge corona unit. 2/2 A4 4-18 FAN5 Development Cooling Fan Cools the development section. 2/2 E6 4-5 FAN6 ID Sensor Fan Provides air flow to the ID sensor. 2/2 A4 4-17 FAN7 Transport Fan (Rear) 2/2 E4 6-11 FAN8 Transport Fan (Front)

Main By-pass Pick-up Solenoid

Sub By-pass Pick-up Solenoid

By-pass Reverse Roller Solenoid

Junction Gate Solenoid Raises the junction gate to feed paper into

Lowers the pick-up roller onto paper.

Positions the reverse roller against the paper feed roller.

Lowers the pick-up roller onto paper. Increases the pick-up roller pressure

depending on the copy mode selected to avoid paper misfeed.

Increases the pressure of the reverse roller against the feed roller depending on the copy mode selected to avoid paper misfeed.

the duplex unit.

Cools the scanner unit.

Holds copy paper against the transport belts.

2/2 G10-G11 1-19

2/2 G10-G11 1-20 2/2 D2 1-12

2/2 D2 1-23

2/2 E2 1-15

2/2 D3-E3 2-9

1/2 G5 4-6

2/2 E4 6-11

1-27

Page 44

ELECTRICAL PARTS DESCRIPTIONS 30 July, 1999 (Revised)

Symbol Name Function

FAN9 Fusing Fan (Upper) 2/2 E6 4-7 FAN10 Fusing Fan (Bottom) FAN11 Exhaust fan Blows air out of the copier. 2/2 A11 4-10

LAMPS

Exposure Lamp Applies high intensity light to the original for

Quenching Lamp (QL) Neutralizes any charge remaining on the

L3 Hot Roller Fusing Lamp Heats to the hot roller. 1/2 C1 6-2 L4 Pressure Roller Fusing Lamp Heats to the pressure roller. 1/2 C1 6-1

HEATERS

Optics Anti-condensation

Heater Paper Transfer Heater Prevents moisture from forming around the

H3 Paper Tray Heater 1 (Option) 1/2 D1 1-27 H4 Paper Tray Heater 2 (Option)

THERMISTORS

TH1 Hot Roller Thermistor Monitors the temperature of the hot roller. 1/2 B1 6-4

Pressure Roller Thermistor Monitors the temperature of the pressure

TH2

Cools the fusing unit area.

exposure.

drum prior to the start of the copy cycle.

Prevents moisture from forming on the optics.

paper transfer belt. Keeps paper dry on the paper feed trays.

roller.

P-to-P

Location

2/2 E6 4-8

1/2 H4 1-2

2/2 A4 5-5

1/2 E1 1-5

1/2 D1 1-26

1/2 D1 1-27

1/2 B1 6-3

Index

No.

THERMOFUSES

TF1 Hot Roller Thermofuse Protects against hot roller overheating. 1/2 B1 6-5 TF2 Pressure Roller Thermofuse Protects against pressure roller overheating. 1/2 C1 6-7

THERMOSTAT

TS1 Thermostat Prevents the scanner unit from overheating. 1/2 H4 1-35

COUNTERS

CO1

CO2

CO3

Total Counter 1 (Upper)

Total Counter 2 (Bottom)

Key Counter (Option)

Indicates the total number of developments made by C, M, and Y.

Indicates the total number of developments made by K.

Indicates the total number of developments of any color.

2/2 A7 1-25

2/2 A7 —

1-28

Page 45

30 March, 1999 PROCESS CONTROL

2. DETAILED SECTION DESCRIPTIONS

2.1 PROCESS CONTROL

2.1.1 OVERVIEW

This copier provides the following three forms of process control:

•

Potential control (done every process control self check)

•

Toner supply control (done every copy)

•

Process control gamma calibration (done after every process control self

check)

The process control facilities of this copier have the following fe atures:

•

Use of a feedback measurement type drum potential sensor.

•

ID sensor (a new type of sensor is used, known as a ‘diffused reflection ID

sensor’). The ID sensor detects the amount of toner on the drum.

•

Use of a toner density (TD) sensor (non-contact communication with the

copier)

Detailed

Descriptions

Revolver

LD Pixel counting Write ASIC

Photoconductive drum

ID sensor

Potential sensor

TD sensor

Fuzzy logic

Toner supply calculation

Motor rotation time

Toner supply motor

Process control

Potential calculation

Development characteristics

Individual potential calculation

Pointer table

2-1

A269D051.WMF

Page 46

PROCESS CONTROL 30 July, 1999 (Revised)

2.1.2 POTENTIAL CONTROL

Overview

Potential control is the process of controlling the development potential to maintain the density of the toner image on the drum. It does this by compensating for variations in drum chargeability and toner chargeability.

The machine uses the image density (ID) sensor to measure drum reflectivity and the density of a standard sensor pattern. It uses the drum potential sensor to detect the potential on the standard sensor pattern (before the pattern is developed). These tests are done during the process control self check, which is done at specific times (such as after replacing the developer).

The ID and drum potential sensor outputs are used to calculate the development potential. This is the difference between the development bias voltage and the voltage of areas of the drum that have been discharged by laser exposure at full power. If changes in this potential are not accounted for, the color balance will be poor.

Depending on the development potential that is calculated, the machine uses a look-up table in memory (called a pointer table) to adjust the following:

•

VD: Drum potential without exposure - to adjust this, the machine adjusts the

charge corona grid voltage (V

•

VL: Drum potential with the strongest exposure - to adjust this, the machine

adjusts the laser diode input current (ILD)

•

VB: Development bias

Potential control controls the development potential so that the maximum amount of toner applied to the drum is kept constant. However, the medium (greyscale) range is ignored. To improve this situation, a new process called ‘process control gamma correction’ is done after potential control. This process defines LD output for all 256 grades of the greyscale (development bias and charge corona grid potential are not affected).

Potential Control Timing

The machine carries out potential control using a procedure called the ‘process control self check’. Process control gamma correction (covered in section 2.1.3) is then done immediately after the process control self check. There are five types of process control self check, categorized according to their execution times. Process control takes approximately 3 minutes.

(1) Forced Process Control Self Check

After replacing the developer or drum, the technician must do the forced process control procedure (SP3-126).

2-2

Page 47

30 March, 1999 PROCESS CONTROL

(2) Initial Process Control Self Check

The initial process control starts automatically when the power is turned on (or when the machine returns to standby mode from sleep mode), but only if the hot roller in the fusing unit is less than 100 degrees centigrade. This process control is done only when SP3-125 (Set Potential Control Method) is set to "0 (Auto)."

(3) Interval Process Control Self Check

The copy interval process control starts automatically at the end of a copy job during which the total number of copies exceeds a preset value.

The preset value can be defined using SP3-973 (Set Process Control Self Check Interval). The factory setting is 150 sheets. The maximum possible interval is 500 sheets. Using a shorter interval reduces the machine’s average copying speed. Setting the process control interval to 0 disables the interval process control.

(4) Timed Process Control Self Check

This process control self check is activated at a predetermined time interval (hours). This check is identical to the interval process control self check. This self check is initiated by entering a value (defaulting to 6 hours) in SP3-972-00. The settable range is 0 to 240. Entering a value of 0 suppresses the execution of this self check.

Detailed

Descriptions

The timer is reset by the following conditions:

•

At the finish of any other process control self-check

•

At the finish of image processing (copying or printing)

•

When the main switch or the operation switch is turned OFF/ON.

•

W hen any door or cover is opened and closed.

•

At the end of toner end recovery.

NOTE:

Just pressing operation panel keys does not reset the timer.

(5) ACC-Run-Time Process Control Self Check

A process control self check that is activated before the execution of ACC (auto color calibration). This check is identical to the interval process control self check.

This process control self check is done when SP4-507 (ACC process control ON/OFF) is set to “3” (Both Copy/Printer ACC). If a value of 0 is entered, this process control self check is not done.

2-3

Page 48

PROCESS CONTROL 30 March, 1999

2.1.3 PROCESS CONTROL

What is process control

γγγγ

CORRECTION

After the process control, the proper values for VD, VB, VL have been defined for the maximum laser power. However, the medium (greyscale) range is ignored. To improve this situation, a new process called ‘process control gamma correction’ is done after potential control. This process defines a suitable LD output for all 256 grades of the greyscale.

Process control gamma correction takes about 30 seconds.

How is it done?

ID sensor

output

Target

Actual

Actual LD

value

VSP range

Input LD value

Target LD value

A269D556.WMF

Based on the maximum laser power just defined during the process control self check, the machine writes another 16-grade sensor pattern on the drum.

NOTE:

The 16-grade pattern for process control gamma is made by varying laser intensity based on the ILD value just determined during the process control self check. This is different from the 16-grade pattern made earlier, which is made using 16 fixed laser power levels.

The ID sensor detects the density developed on these patterns and compares them with the target densities in ROM. The target densities and the actual densities can be plotted as shown in the diagram above left.

NOTE:

To make the curve of actual densities, the machine draws a curve (interpolates values) through the density points read from the 16-grade pattern made for process control gamma.

From this, the machine determines how much to correct the LD power when attempting to write a certain density on the drum.

In the example in the diagram, for a laser power of A, the machine expected an ID of B. However, the actual result was C. To get an ID of B, the machine has to use a laser power of D. The expected ID can be plotted against the actual ID as shown in the diagram above right; this is the process control gamma curve.

2-4

Page 49

30 March, 1999 PROCESS CONTROL

Process control γ target is stored in the NV-RAM on the main control board. The CPU calculates the process control γ on the main board. The results of process control γ calculation go to the LD main control board to compensate the LD input data.

The process control gamma obtained cannot be adjusted in SP mode.

Process Control

γγγγ

Correction Timing

The machine automatically does process control gamma correction at the end of every process control self check.

Relationship Between Process Control

γγγγ

Correction, ACC, and Other

γγγγ

Corrections

Process control γ correction is executed so that the amount of toner attached to the drum against the LD write value has the intended characteristic within the process range between LD write and development section. However, the ACC correction encompasses the process range from scanning to image generation (including the scope of process control γ correction).

Potential control and process control γ correction have different goals. The ultimate purpose of potential control is to adjust the maximum amount of toner attached to the drum against the development potential to a certain target value. Process control γ correction, however, adjusts the amount of toner at all levels of the 16 gradation patterns to the target characteristics and interpolates between the 16 adjusted levels to make all 256 grayscale grades. This correction is used to make the image characteristics in low ID sections closer to the target value.

Detailed

Descriptions

2-5

Page 50

PROCESS CONTROL 30 March, 1999

2.1.4 PROCESS CONTROL SELF CHECK OPERATION FLOW

Start

Adjust ID sensor V

Generate patch patterns

Sense with potential sensor

Sense with ID sensor

Calculate amount of toner

Calculate development

characteristics

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Determine optimum VD, VB, and

VL from potential table

End

2-6

Step 7

A269D052.WMF

Page 51

30 March, 1999 PROCESS CONTROL



 

Step 1: VSG Adjustment

The type of ID sensor used in this machine responds differently for black and color, so there are two V

The type of ID sensor used in this machine is very sensitive, and outputs some voltage even if there is no light being reflected off the drum. This output is known as the ‘offset’. It is about 1 V for black and about 0.2 V for color. For more details on this sensor (known as a ‘diffused reflection ID sensor’), see ‘Step 4: Sensor Pattern Density Detection’.

The ID sensor checks the bare drum’s reflectivity and the machine calibrates the output of the ID sensor as follows. This voltage is known as VSG:

•

(1.8 + offset) ± 0.05 V

This calibration compensates for the drum’s condition (due to ageing) and the ID sensor condition, such as dirt on the surface of the drum or ID sensor.

Note that VSG for black is less than half of that in previous models. This is due to the new type of ID sensor, which is described in a later section.

values, one for black toner and one for CMY toner.

Detailed

Descriptions

Step 2: Generating ID Sensor Patch Patterns

The machine makes a 16-grade pattern on the drum for each toner color. Each grade of the pattern is made by changing the LD power. At this stage, the patterns are not developed; they remain as latent images.



 

 

A269D054.WMF

2-7

Page 52

PROCESS CONTROL 30 March, 1999

Step 3: Sensor Pattern Potential Detection

Process

The drum potential sensor det ects the potential on each grade of the 16-grade sensor pattern latent image, for each color, and the output is stored in memory.

Feedback Type Drum potential Sensor

[B]

[A]

Feedback circuit

A269D053.WMF

This copier uses a feedback drum potential sensor. The detector [A] detects the strength of electric fields emitted from the drum

surface, which depend on the surface potential of the drum. The feedback circuit applies voltage to the probe [B] until the electric field strength is offset at the detector. The level of this voltage determines the magnitude of the potential on the drum surface and is presented as output.

The major features of this measurement method are:

•

Even if the distance [d] between the drum (1) and the drum potential sensor (2)

fluctuates, the measurement of the drum surface potential is still accurate.

•

The drum potential sensor does not have to be calibrated before the process

control self check, so the calibration step required for previous models can be skipped.

•

Residual voltage affected the calibration for the older type of sensor, so before

process control self checks, the machine had to wait 10 minutes in standby mode for the residual voltage to disappear. For this new sensor, calibration is not needed, so the influence of residual voltage on the drum can be ignored.

2-8

Page 53

30 March, 1999 PROCESS CONTROL

Step 4: Sensor Pattern Density Detection Process

The development rollers of the respective colors develop the sensor pattern latent images for K, Y, C, and M generated in Step (2). In Step (4), the ID sensor detects the densities of the 16 patch patterns for each color. This data goes to memory.

Diffused Reflection ID Sensor

Direct Reflection Type ID Sensor

Drum

Toner

Detector

LED Detector

A269D056.WMF

Diffuse Reflection Type ID Sensor

Drum

LED

Diffuse Beams

A269D057.WMF

Toner

This copier uses a diffused reflection ID sensor. In addition to the ray directly reflected from the drum, there are diffuse beams reflected at all angles from the toner on the drum. This sensor detects image density by receiving some of these diffuse beams, not by receiving the beam directly reflected from the toner.

Using this type of sensor improves the measurement accuracy of the sensor pattern densities particularly for Y, C, and M toners.

Detailed

Descriptions

Color (Y, C, M) toners

Direct Reflection Type ID Sensor Diffuse Reflection Type ID Sensor

min

A269D058.WMF

(1): Component of light reflected from the drum (2): Component of light reflected from C, M, or Y toner

[Figure A]

Relationship between the output of the normal reflection type ID sensor and the amount of toner on the drum for C, M, and Y toners

= (1) +(2)

(1)

(2)

M/A

2-9

A269D059.WMF

[Figure B]

Relationship between the output of the diffused reflection ID sensor and the amount of toner on the drum for C, M, and Y toners

M/A

Page 54

PROCESS CONTROL 30 March, 1999

Figure A shows the relationship between the output of the normal reflection ID sensor and the amount of Y, C, or M toner attached to the drum. This shows that the ID sensor output (Vsp) results from not only the light reflected from the toner but also the component of light reflected from the drum.

Therefore, high densities of colored toner (i.e., to the right of the minimum point in the VSP curve at Vmin) cannot be measured.

The diffused reflection ID sensor, on the other hand, picks up little light that is reflected from the drum. Therefore, the relationship between the diffused reflection ID sensor output and the amount of toner attached to the drum is linear, as shown in Figure B. This means that high densities of colored toner can be measured accurately.

K Toner:

[Figure C]

Relationship between the output of the diffused reflection ID sensor and the amount of toner on the drum for K toner

M/A

A269D060.WMF

The ID sensor output for K toner tends to decrease as the density of toner on the drum increases. Therefore, the relationship between the ID sensor output and the amount of K toner on the drum is as shown in Figure C.

2-10

Page 55

30 July, 1999 (Revised) PROCESS CONTROL

Step 5: Toner Amount Calculation

The amount of toner on the drum (M/A, mass per unit area, mg/cm2) is calculated for each of the 16 grades of the sensor pattern from the ID sensor output value (Vsp) from each grade of the pattern.

Step 6: Development Potential Calculation

The development potential (VDP) is the capability to attract toner to the drum and can be shown as: V

•

VB: Development bias

•

VL: Drum potential after full laser

- V

exposure

See the figure on the right for two examples.

The machine determines the relationship between the drum potential (measured in step 3) and the amount of toner on the drum (calculated in step 5) for each of the 16 grades. If plotted, these values would form a curve as shown in the illustration to the right. The CPU then calculates a straight line curve through these points. The angle formed by this line is known as the development gamma factor, or γ M/A. The CPU then uses the gamma factor to calculate the development potential

) that would be required to obtain

the ideal toner density on an area of the drum exposed with full laser power under the machine's present conditions.

Amount of toner on the drum

When the development potential is smaller

MAmax

Amount of toner

Development potential

When the development potential is larger

A269D061.WMF

MAmax = 0.7 mg/cm for each color

Vdp

Vkp

Detailed

Descriptions

A269D062.WMF

For Y, C, and M toners, the new type of ID sensor allows higher densities of toner to be measured accurately (refer to the descriptions in Step 4, Sensor Pattern density Detection). This permits the calculation of γ M/A at a higher accuracy than a normal reflection ID sensor, because the measurements at higher densities (M/A values) are more reliable.

2-11

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PROCESS CONTROL 30 March, 1999

Step 7: Selecting the Optimum VD, VB, V

The machine now adjusts VD, VB, and VL to try to bring the development potential VDP to the ideal value. To do this, it uses a pointer table. This is a look-up table in ROM of VDP against VD, VB, and V

The machine takes the value of VDP calculated in the previous section, and looks for the value of VDP in the pointer table that is closest to this. The machine reads the values of VD, VB, and VL that are in this row of the pointer table.

The machine will then use these values of VD, VB, and VL during copying until the next process control self check. These values are designed to bring the actual V

to the optimum value for the machine’s current condition.

•

VD: Drum potential without exposure—to adjust this, the machine adjusts the

charge corona grid voltage (VG)

•

VL: Drum potential with the strongest exposure—to adjust this, the machine

adjusts the laser diode input current (ILD)

•

VB: Development bias

2-12

Page 57

30 March, 1999 PROCESS CONTROL

2.1.5 TONER SUPPLY CONTROL

This machine uses fuzzy logic to control the amount of toner supplied to the development unit so that the development capacity does not fluctuate due to toner consumption, toner supply, agitation, or extended periods of nonuse. This control is accomplished using the sense data from the drum potential sensor, toner end sensor, ID sensor, and TD sensor. This copier starts toner supply control by keeping the toner density in the developer constant using the TD sensor. It then senses the amount of toner on the drum using the ID sensor pattern. The ID sensor sends the pattern data back to the toner supply control mechanism and the amount of toner on the drum surface (image density) then becomes the target. The TD sensor provides a stable base point for toner supply and thus avoids runaway feedback of toner supply. The basic input/output parameters that this copier uses during toner supply control are listed below.

1. Targets to be sensed

1) Density of the toner read by the TD sensor

2) Amount of toner attached to the drum sensed by the ID sensor

3) Pixel count

Detailed

Descriptions

2. Target to be controlled Toner supply clutch on time

Toner Supply Control Modes

This copier controls the supply of toner in three modes.

1. Fuzzy logic Control Mode Default toner supply control mode. The TD sensor, ID sensor, and pixel count are used in this mode.

2. Proportional Control Mode This mode is used when an ID sensor becomes faulty. Only the TD sensor is used to control toner supply.

3. Fixed Supply Mode This mode is used when both the TD sensor and ID sensor become faulty.

2-13

Page 58

PROCESS CONTROL 30 March, 1999

TD Sensor Output

The relationship between the TD sensor output Vt and the toner density in the developer is shown in the figure on the right. The target toner density of this copier is 5 WT%. The TD sensor output for this toner density is referred to as Vref. Vref of this copier is adjusted to 2.5 ± 0.1 volts for a toner density of 5 WT% (brand-new developer) for each of the C, M, Y, and K toners. When developers are replaced, since TD sensor fluctuations can occur in such a case, it is necessary to initialize the TD sensor and adjust its gain using SP3-005-1 through SP3-005-5. Once the TD sensor is initialized, the toner density fluctuates according to toner supply control.

Relationship between toner density and TD sensor output

A269D063.WMF

Toner Supply Calculation

In the fuzzy logic control mode, the toner supply control mechanism of this copier determines the amount of toner to be supplied based on the density of the toner in the developer, as sensed through the TD sensor, and the pixel count. In this mode, the image density is kept constant by keeping the density of toner in the developer constant while accommodating to changes in the development conditions through the potential control mechanism. The amount of toner supplied is determined by the ON time of the toner supply clutch.

Detecting VSP for Toner Supply Control

The copier generates a VSP ID sensor pattern (right illustration) using a standard laser diode power. The copier generates this pattern between the K, C, M, and Y images, and then detects the density using the ID sensor. The result is known as ‘VSP for toner supply control’, or ‘VSP (toner)’ to distinguish it from the othe r VSP, measured during potential control.

This process is done every ten copies.

25 mm

30 mm

2-14

A269D065.WMF

Page 59

30 March, 1999 PROCESS CONTROL

Calculating the Amount of Toner on the Drum

The target for the ID sensor pattern is 0.7 mg/cm2 for the C, M, and Y toners and

0.3 mg/cm2 for the K toner. For the procedure to calculate the amount of toner on

the drum, see Step 4, “Sensor Pattern Density Detection,” and Step 5, “Toner Amount Calculation” in the section about potential control.

Toner Near End/Toner End Detection

Introduction

This copier uses the toner end sensor located in the toner hopper to detect toner near end conditions for the K, Y, C, and M toners. A toner end condition, for each color, is detected following a toner near end condition by counting the number of pixels. (See “Toner End Detection” on the next page.)

Toner Near End Detection

This copier uses an optical reflection type toner end sensor to detect two conditions—the high condition (5 V: no reflection/toner present) and the low condition (0 V: reflection detected/no toner). The copier samples the output from the toner end sensor at the development position for each toner color, for 160 samples at 4 ms intervals. A “toner absent condition” is flagged when more than 20 low sensor output conditions are detected out of 160 sampled conditions. The copier flags a “toner near end condition” when three consecutive “toner absent conditions” are detected for a toner color.

Example 1: 3 full color copies, rep eat mo de

•

20 sensor low conditions detected out of 160 sampled conditions while

developing the first copy sheet for K

•

25 sensor low conditions detected out of 160 sampled conditions while

developing the second copy sheet for K

•

24 sensor low conditions detected out of 160 sampled conditions while

developing the third copy sheet for K

Detailed

Descriptions

↓

The K toner near end LED is lit.

2-15

Page 60

PROCESS CONTROL 30 July, 1999 (Revised)

Example 2: 4 full color copies, repeat mode

•

20 sensor low conditions detected out of 160 sampled conditions while

developing the first copy sheet for Y

•

19 sensor low conditions detected out of 160 sampled conditions while

developing the second copy sheet for Y

•

21 sensor low conditions detected out of 160 sampled conditions while

developing the third copy sheet for Y

•

25 sensor low conditions detected out of 160 sampled conditions while

developing the fourth copy sheet for Y

•

21 sensor low conditions detected out of 160 sampled conditions while

developing the fifth copy sheet for Y

↓

The Y toner near end LED is lit.

Toner End Detection

After a toner near end is indicated, the toner end condition is reached when the IPU pixel counter counts up the equivalent of 10 A4 sheets of pixels (100% coverage) for that color.

The machine can copy/print at least 10 sheets after the toner near end condition is signaled. There are two possible cases as follows:

1. The toner end condition occurs before 10 sheets are printed: In this case copying stops after 10 sheets are printed. This is true regardless of paper size.

2. Ten sheets (of any size) are printed before toner end occurs: In this case copying stops when the toner end condition occurs.

Toner End Recovery

The copier enters the recovery process in the following cases:

1. The front door is opened and a toner cartridge is removed or inserted. This is regarded as an ordinary replacement procedure for the toner cartridge.

•

When the door is closed, the copier moves the next to-be-replaced color

toner cartridge to the replacement position.

↓↓↓↓

•

Replace the toner cartridge.

↓↓↓↓

•

The copier starts toner end recovery processing after the toner cartridge is

replaced and the front door is closed.

NOTE:

If recovery is needed for two colors, the copier proceeds with the next color if the door is opened or if the user specifies at the operation panel that the first color should be skipped.

2. If the copier is turned off and on, it assumes that toner cartridges for all colors have been replaced and starts toner end recovery processing for all colors.

2-16

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30 March, 1999 DRUM UNIT

2.2 DRUM UNIT

2.2.1 MAJOR COMPONENTS

Detailed

Descriptions

A269D201.WMF

1. Charge corona unit

2. Quenching lamp

3. Cleaning blade

4. Lubricant bar

5. Bias roller blade

6. Bias roller

7. Cleaning brush

8. Pre-cleaning corona (PCC)

9. Carrier catcher

10. ID sensor

11. OPC drum

12. Drum potential sensor

This drum unit of this copier is located on the right of the revolver/drum drawer. It can easily be removed by pulling out the drawer.

The drum unit consists of the OPC drum, charge corona unit, quenching lamp, drum potential sensor, and cleaning unit.

The cleaning unit is integrated in the drum unit because, since the cleaning unit is located in the top portion of the copier, toner would spill out of the opening if the drum unit were removed or installed by itself. The cleaning unit contains the cleaning blade, lubricant bar, and cleaning brush.

2-17

Page 62

DRUM UNIT 30 March, 1999

2.2.2 DRUM UNIT DRIVE

[A]

[C]

[D]

[B]

A269D202.WMF

[G]

[F]

[B]

[E]

[H]

A269D203.WMF

Drum Drive

The drum motor [A] turns the OPC drum [B] via a timing belt [C]. Use of the timing belt reduces rotational fluctuations, thus stabilizing image quality (reduce uneven image).

The motor has a built-in rotational speed control circuit. When the rated rotational speed is not achieved, the rotational speed control circuit generates a motor clock signal, which turns on SC440 (Drum Motor Error) and stops the copier.

The drum is rotated in the reverse direction for 0.05 second (approx. 10 mm) to remove the toner at the tip of the drum cleaning blade at the end of the initial auto process control self check.

The drum shaft is fitted with a flywheel [D] to smooth the rotation and prevent banding of the image.

Cleaning Drive

The drum peripheral component motor [E] drives the cleaning unit (cleaning brush [F], bias roller [G], and toner collection coil [H]).

2-18

Page 63

30 March, 1999 DRUM UNIT

2.2.3 CHARGE CORONA UNIT

Detailed

Descriptions

A269D204.WMF

This copier uses a single wire scorotron system to charge the drum. The output of the charge high voltage power supply is -6 kV.

A grid keeps the surface potential of the drum at –670 V (standard value). The grid bias voltage is corrected so that the surface potential remains constant by

sensing the surface potential of the drum with the drum potential sensor. The exhaust fan at the rear of the copier, causes air to flow into the charge corona

unit from front to rear sides. This helps prevent uneven charging.

2-19

Page 64

DRUM UNIT 30 March, 1999

2.2.4 CHARGE CORONA UNIT CLEANER

The copier is provided with a charge corona unit cleaner to prevent the charge corona wire and grid from becoming contaminated by toner and paper dust near the charge corona unit.

•

Drive:

Dc motor [A] located on the copier front, via screw rod [B].

•

Cleaning conditions:

1) When th e main power switch is on and the surface temperature of the hot roller is less than 100°C.

2) When forced using SP mode (SP2-

802).

•

Related SP mode s:

1) SP2-02: Forced cleaning

2) SP2-803-001:Enable cleaning when main power switch/operation switch is turned on (default is ON)

3) SP2-803-002:Enable cleaning at specified development cycle count (default is ON)

4) SP2-803-003: Enable cleaning at a specified time interval (hours). (Default is OFF)

[B]

[A]

A269D251.WMF

[D]

[C]

•

Cleaner pad:

Dual-grid cleaner pad [C] and wire cleaner pads [D].

•

Home position:

Copier front

•

Cleaning path:

Copier front → Rear end point → Copier front Only the charge corona grid is cleaned during the traverse from copier front to rear end (white arrow). Both the charge corona grid and wire are cleaned during the traverse from rear end point to copier front (black arrow).

•

Position detection:

No sensor is used. The I/O control board detects the current that is being supplied to the motor. It senses the sudden change in the current value which occurs when the cleaner reaches the end point. At the turnaround point, the motor is reversed. If no current rise is observed in 60 seconds after motor rotation starts, the I/O control board an open circuit or disconnected condition, stops the motor, and displays SC303.

2-20

Page 65

30 July, 1999 (Revised) DRUM UNIT

2.2.5 CLEANING MECHANISM

Cleaning

[C]

After toner is transferred to the OPC drum in the transfer process, the residual toner is removed from the drum by the drum cleaning brush [A] and blade [B]. The cleaning brush is a straight fiber brush (not looped) type. The cleaning bias system uses a rotating bias roller [C] and scraper blade [D]. The bias roller and the brush

[B]

rotate opposite to each other at the point of contact. The cleaning blade is of the counter type. It is constantly held against

[A]

[D]

the drum by a spring.

A269D205.WMF

Lubricant Application

Lubricant (Zinc stearate) is applied to the OPC drum via the cleaning brush. The lubricant bar is held against the brush by the weight of the drum lubricant bar plus spring pressure. Lubricant is applied is to improve the efficiency of cleaning and of image transfer.

Detailed

Descriptions

2.2.6 PRE-CLEANING CORONA (PCC)

The PCC discharges the photoconductor drum and applies AC and negative DC discharges to reduce the charge holding the residual toner to the drum, thereby improving the efficiency of cleaning.

[A]

A269D206.WMF

2-21

Page 66

DRUM UNIT 30 March, 1999

2.2.7 QUENCHING

This copier employs optical quenching using LEDs. The quenching lamp [A] turns

[A]

on immediately when the Start key is pressed. The quenching lamp light is in the red range to protect the drum from optical fatigue.

A269D207.WMF

2.2.8 CARRIER CATCHER

This copier has a magnet [A] installed below the ID sensor [B]. This magnet attracts carrier from the drum.

[A]

[B]

A269D208.WMF

2-22

Page 67

30 March, 1999 SCANNER UNIT

2.3 SCANNER UNIT

2.3.1 OVERVIEW

[A] [C] [F] [D]

[D][B]

A269D001.WMF

Detailed

Descriptions

An image of the original illuminated by the exposure lamp [A] (a halogen lamp) is reflected onto a color CCD [B] (Charge Couple d Device) via the 1st [C], 2nd [D], and 3rd [E] mirrors, filter, and lens [F]. The filter removes infra-red from the light reflected off the original; this is particularly important for glossy photos with black areas, which can appear reddish in copies.

For all copy modes except the “Auto Original Type” mode machine makes a single scan. The CCD is a one-chip color CCD with RGB color filters. The scanning resolution is 400 dpi (5,000 pixels).

2-23

Page 68

SCANNER UNIT 30 March, 1999

2.3.2 SCANNER

[B]

[C]

[D]

[E][A]

A269D001.WMF

The 1st scanner consists of the exposure lamp [A], main and sub reflectors [B], and 1st mirror [C]. This model uses a halogen lamp with ten elements. The frosted surface of the exposure lamp ensures even exposure in the main scan direction.

The exposure lamp is energized by a dc supply to avoid uneven light intensity caused by power fluctuations while the 1st scanner moves in the sub-scan direction. The sub reflector is shaped so that light will expose the original evenly. This reduces shadows on pasted originals.

The 1st, 2nd [D], and 3rd [E] mirrors have glass on the reverse sides to increase their weight. This prevents the mirrors from vibrating.

A thermoswitch in the 1st scanner protects against overheating. It will open at around 140°C and cannot be reset.

2-24

Page 69

30 March, 1999 SCANNER UNIT

2.3.3 SCANNER DRIVE

[A]

[B]

[C]

A269D002.WMF

A five-phase stepper motor [A] drives the scanner. This motor drives the 1st [B] and 2nd [C] scanners via two scanner wires. The wires at the front side and the rear side are the same.

In full size mode, the 1st scanner speed is 200 mm/s during scanning, and 1,200 mm/s when the scanner returns. The 2nd scanner speed is half that of the 1st scanner.

Detailed

Descriptions

Forwarding Speed Returning Speed

Full Size Mode 200 (mm/s) 1,200 (mm/s) Reduction or Enlargement Mode 200/M (mm/s) 1,200 (mm/s)

In reduction or enlargement mode, the scanning speed depends on the magnification ratio “M”, which can vary from 0.25 to 4.0 (i.e., 200/M mm/s). The returning speed is always the same (1,200 mm/s). The image length is changed in the sub-scan direction by changing the scanner speed, and in the main scan direction by image processing on the scanner IPU board.

For all copy modes except the Auto Original Type mode the machine makes a single scan.

2-25

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SCANNER UNIT 30 March, 1999

2.3.4 COLOR CCD

2 31

5000

A269D150.WMF

The color CCD converts light reflected from the original into three analog signals, one for each of the three basic colors Red, Green, and Blue. The signals are called the R, G, and B signals. A single scan generates a separate set of three signals (RGB).

The CCD consists of three lines of 5000 elements at a resolution of 400 dpi (15.7 dots/mm). To make the R, G, and B signals, each line has a color separation filter (R, G, or B). The lines are spaced 4 pixels apart for full size magnification. To correct for the spacing, the R, G, and B signals must be synchronized. This is done by delaying the signals in memory buffers on the scanner IPU board (the Image Processing section contains more details).

The CCD is mounted on the board with the lens block (the assembly is known as the SBU or Sensor Board Unit). Therefore, to replace the CCD, re place the SBU.

2-26

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30 March, 1999 SCANNER UNIT

2.3.5 WHITE PLATE SCANNING

[A]

[B]

A269D851.WMF

There is a white plate [A] for auto shading, stuck on the exposure glass [B] underneath the left scale. When this white plate is scanned, the output from all the CCD elements in a line should in theory be equal, but actually it is no t, for the following reasons:

Detailed

Descriptions

•

Variations in sensitivity between elements of the CCD

•

Variations in characteristics of lens and mirror reflectivity

•

Loss of brightness toward the ends of the exposure lamp

To correct for this uneven output from the CCD elements, the light reflected from the white reference plate is scanned. This is known as auto shading.

Auto shading is done every copy cycle at the scanner home position before starting the first scan.

2.3.6 SCANNER IPU

The scanner IPU processes the RGB signal received from the CCD board and has the following functions under the control of the main control board.

1. Controls exposure lamp on/off switching and voltage

2. Controls the speed of the scanner drive motor

3. Detects the original paper size

4. Controls on/off switching for the IPU cooling fan and optics cooling fans

5. Supplies the clock signals for the CCD board

6. Detects when the scanner is at home position

2-27

Page 72

SCANNER UNIT 30 March, 1999

2.3.7 ORIGINAL SIZE DETECTION

[A]

“

”

•

[C]

[B]

A269D003.WMF

’

‘

•

A269D005.WMF

Sensing Point

••••

•••• ‘‘‘‘ ’’’’ ““““ ””””

••••

From rear left corner

376.23 276.23

351.83 206.68

321.78 182.28

198.00 113.00

136.00 161.50

140.00 200.00

136.00 238.50

2-28

Page 73

30 March, 1999 SCANNER UNIT

Original Size Setting Point

A4/A3 Version (metric)

A3 11" x 17"

B410" x 14"0 1 ———— 1 141

—8

A4-S 11" x 8 A4-L 8

B5-S — 0000——1 14 B5-L — 0001100 142 A5-S 8 A5-L 5

LT/DLT

Version

(inch)

(11" x 15")

1/2

" x 14"0 1 ———— 0 164

1/2

" x 13"

(8" x 13")

1/2

" x 11"

(8" x 10")

1/2

1/2" x 81/2

" x 5

1/2

•••••

1 —————— 132

0 0 1 ———— 165

"00011—1 5

0001110 133

"00001—0 6

"00010——134

•‘

••

‘’

‘‘

’“

’’

“”

““

”•

””

L: Lengthwise S: Sideways

0: OFF, 1: ON —: Don’t care

•

••

Display

Detailed

Descriptions

There are three APS sensors (reflective photosensors) in the optics cavity for original size detection. The original width sensor [A] detects the original width, while the original length sensors [B] and [C] detect the original length.

The original width sensor [A] and the original length sensor [B] have three internal beams. Each beam scans a different point of the exposure glass. The other original length sensor [C] uses only one beam.

If the original or platen cover is present over the scanning point for a particular sensor, the beam is reflected, and each reflected beam activates a photoelectric device. Following diagram shows where the sensing points are.

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SCANNER UNIT 30 March, 1999

2.3.8 OTHERS

[C]

[B]

[A]

A269D004.WMF

Anti-condensation Heater

There is an anti-condensation heater [A] on the right side of the SBU. It turns on when the main switch or operation switch is off, to prevent moisture from forming on the optics.

Fans

1. Optics Cooling Fans The optics cooling fans [B] are on the left side of the optics cavity. There fans draw air into the optics cavity to prevent the exposure lamp and optics cavity from overheating during copy cycles. They turn on at the same time as the exposure lamp, and they turn off 10 seconds after the exposure lamp turns off.

2. IPU Cooling The IPU cooling fan [C] is on the left rear side of the optics cavity. This fan moves air out of the optics cavity to keep the IPU from overheating. This fan is always on when the operation switch is on. Normally it turns at half-speed. However, it goes to full-speed when the exposure lamp turns on, and it returns to half speed 10 seconds after the exposure lamp turns off.

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2.4 IMAGE PROCESSING

2.4.1 OVERVIEW

Scanner IPU Board

CCD

Scanner

Section

IPU

Section

Detailed

Descriptions

Scanner

LD Unit

Drive

Board

Main

Control

Board

Image

Data

Main

Control

Board

Printer

A269D066.WMF

The reflected light from the original enters the CCD via the mirrors and lens. The CCD board has a CCD chip that is provided with a filter for each of the R, G, and B colors. The reflected signal is converted to analog signals (photoelectric conversion) and sent to the scanner IPU board as image data.

The scanner IPU board performs signal processing, A-to-D conversion, shading compensation, D-to-A conversion, line correction, and image processing on the image data. The image data is finally supplied to the printer section as digital signals (8 bits per pixel).

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2.4.2 SCANNER SECTION BLOCK DIAGRAM

Analog

ASIC

Converter

10bit

Field

Memory

10bit

4 Mbit

Field

Memory

10bit10bit

IPU

Section

C C

CCD

AGC

Analog

ASIC

Ref

Converter

10bit

Shading

Circuit

AGC

Analog

ASIC

AGC

D/A

Converter

Ref

Converter

Ref

CPU

2 Mbit

10bit10bit

A269D067.WMF

The RGB analog image signals from the CCD are combined and amplified by analog ASIC chips and converted to 10-bit digital signals by A/D converters. The digital signals undergo shading compensation and line correction before being sent to the IPU section.

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2.4.3 SCANNER FUNCTIONS

Photoelectric Conversion

The color CCD converts the light reflected fro m the original into RGB analog signals (6.615 MHz for each signal: even-pixel and odd-pixel). Each CCD line has 5,000 pixels and the resolution is 400 dpi (15.7 pixels/mm).

Signal Processing (Analog ASIC)

This analog ASIC provides the following three analog signal processing functions:

(1) Signal Amplification

Odd-pixel and even-pixel RGB analog signals from the CCD are amplifie d by operational amplifi ers .

(2) Signal Composition

The amplified signals (even-pixel and odd-pixel for each RGB color) are combined by the MPX before A/D conversion.

Detailed

Descriptions

(3) Feedback

The CPU on the scanner IPU board receives the feedback data for white level and black level from the shading circuits and feeds it to the ASICs through the D/A converter. The feedback data from the CPU are updated every time the

main

switch is turned on.

A/D Conversion

The A/D conversion block converts the analog signals (CCD output) to 10-bit (1024 gradations) digital signals.

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Shading Compensation Circuit

(1) Shading compensation

Before scanning each original, the machine generates a reference white waveform (also known as "white shading data") by scanning 5 mm of the white

reference plate [A] in the sub-scan direction (this equals 79 lines at 100% magnification).

The white shading data is calculated for each pixel across the main scan. To do this for a particular pixel, it takes the white

A269D068.WMF

levels for that pixel on each of the main scan lines taken from the white reference plate, and calculates a value from these. The white waveform is made by repeating this process for each pixel across the main scan.

To improve image reproduction for high density areas, the machine also measures the black shading data. It does this by reading the black video level at the first 4 pixels of the CCD, which should be black because these pixels are masked off. The average of the 4 pixels is represented as the black shading data for one CCD scan line.

White Correction

Black Correction

1 line

1023

1 line

A269D069.WMF

The video signal for each pixel obtained during image scanning is corrected by the shading circuit as follows:

(Data scanned for each pixel) - (Black correction data)

x 1023

(White correction data for each pixel) - (Black correction data)

The white shading data are updated before every scanning. The black shading data are updated every scan line. The white shading data corrects the image data for irregularities in the CCD an d th e optics across the main scan. The black

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30 March, 1999 IMAGE PROCESSING

shading data corrects the image data for any changes in black level with time, as the machine scans down the page.

D/A Conversion

The CPU monitors the digital feedback signals from the shading circuits and calculates correction factors. Then the D/A circuit converts the signals from the CPU into analog signals and feeds them back to the analog ASIC chips.

The CPU feeds black shading data back to the AD converters as the reference black level. This is for done every CCD pixel to calibrate the black level, to avoid drifts in the signal with time.

Scan Line Correction Circuit

Detailed

Descriptions

Enlargement

Reduction

Full Size

5 lines 5 lines

3 lines

1 2 3 4 5 6 7 8 9 10 11 12 13

G R

4 lines 4 lines

G R

3 lines

G R

A269D070.WMF

The three CCD lines providing the RGB signals are spaced 4 line s apart (8 lines total) when full size magnification is used. To compensate for this discrepancy, the line correction circuits synchronize the output timing of the RGB signals to the IPU section by storing the scan data for each line in memory. The discrepancy between RGB video signals changes depending on the magnification ratio. The correction data for different magnifications is calculated as follows:

•

B: Standard (No correction)

•

G: (4 lines) x (Magnification ratio)

•

R: (8 lines) x (Magnification ratio)

If this calculation does not result in an integer, the correction data is set to the closest integer, but further correction is needed (refer to “Picture Element Correction”).

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2.4.4 IPU SECTION BLOCK DIAGRAM

Gradation

processing

Image

Creation

Magnification

Color

calibration

ACS

Separation

DRAM

Filter

Field

Color

Memory

Picture

Element

Correction

Memory

Shading

calibration

Field

Memory

Area processing

DRAM

This copier holds RGB color image data in 96 MB of DRAM memory so that a full-color copy can be generated in a single scan. The image in this

memory is also used in the continuous copy mode.

In single color mode, this memory can be used to enable image rotation.

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2.4.5 IPU FUNCTIONS

Scanner

γγγγ

Conversion and Picture Element Correction

γγγγ

Conversion (RGB

1023

Dark Light

A269D072.WMF

γγγγ

Conversion)

255

1023

LightDark

A269D073.WMF

The RGB video signals from the CCD (10-bit signal) are sen t to the IPU section . These signals are proportional to the intensity of light reflected from the original image (Fig. 1). However, the IPU section converts the signal levels as shown in

figure 2 by us ing a gamma (γ) correction table in order to improve the accuracy of RGB to CMY color conversion, which is done later in the image process. The same table is used for R, G, and B signals.

Detailed

Descriptions

The scanner gamma (γ) correction inverts the video signals and converts the signal from 10-bit to 8-bit as outlined in the following table:

Dark (Black) Light (White)

Scanner Input (RBG) 0 1023

After γ Correction (RGB)

↓

Color Conversion

↓

Printer Output (CMYK) 255 0

255 0

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

Picture Element Correction

The Picture Element Correction circuit does two things.

1. Completion of the Scan Line Correction process

The discrepancy in the spacing of the RGB signals from the CCD in the sub -scan direction

is corrected by the line correction circuit in the scanner section (refer to Scanner Section –

Scan Line Correction). However, if the correction data corresponding to the

magnification ratio is not an integer, then further correction is needed to synchronize the RGB signals.

Picture Element Correction

A269D074.WMF

2. Correction if the CCD is not perpendicular to the light

If the CCD board is not perpendicular to the light axis, the position of each pixel is different from the original image position. This difference becomes larger towards the ends. Under this condition, vertical black lines (in the sub-scan direction) at the left and right edges of the original are colored because the Y, M, and C toner dots are not properly positioned. (This can be checked by looking at the vertical lines at the right and left edges of a copy of the C4 color chart.)

Therefore, the CCD line spacing is also corrected here. The target areas for this correction are shown above. The green CCD line is taken as a standard, and the ends of the red and blue lines are corrected.

Adjust SP modes 4-932-001 to 4-932-004 to chang e the v erti cal line correction level. (See 6.7.2 Main Scan Position Dot Correction)

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ACS (Auto Color Selection)

A269D076.WMF

A269D075.WMF

The auto color selection function determines if an original is black/white or color. Then black copy mode or full color mode is automatically selected to match the original.

Detailed

Descriptions

To recognize if the original has a color area or not, the RGB video signals are compared. If the maximum difference among RGB signal levels (MAX-MIN in the above diagram) is within a certain range, the original is considered black and white.

During the 1st scanning cycle, the latent image is developed with the amount of black toner specified by the gamma (γ) corrected RGB video signals. If the original does not have any color areas, the 2nd scanning is aborted and the developed image is transferred from the transfer belt to the copy paper. Then the black & white copy comes out. If the original has a color area, copying resumes in the full color copy mode (4 scans).

Users can maximize the quality of their output by selecting priority for black and white or full color original in ACS mode, using the User Tools (ACS Priority). (The above right figure shows the effect of this setting.) The K setting prevents the UCR process from reducing the image density too much in low image density photo areas. This is explained in more detail in the section on UCR.

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IMAGE PROCESSING 30 March, 1999

Automatic Original Type Selection

If this function is selected, the copier starts a pre-scan when the Start key is pressed. During the pre-scan, the copier detects two or more image features and identifies the type of original.

Since the copier selects the mode that is most suited to the original, the selected mode does not always match the specified mode. For example, the copier may not copy text originals in the text mode.

The copier automatically selects the following 9 original modes: Automatically selected original modes

1) Text mode

2) Printed text/photo

3) Glossy text/photo

4) Copied text/photo

5) Printed photo

6) Glossy photo

7) Copied photo

8) Marker pen

9) Ink jet

NOTE:

Mixed-type originals are disallowed because the copier cannot select an appropriate mode for such originals (they may be copied, however).

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Image Separation

The copier senses and separates the original image into text and photo (dot screen) areas. Generally, The text areas feature an appreciable difference in contrast between the background and image parts. The photo (dot screen) areas feature many intermediate levels of gradation.

The copier senses these features and separates the image into black text, colored text, and photo areas.

Edge Separation

Text Area

A269D077.WMF

Detailed

Descriptions

•

Black Text

•

Colored Text

•

Dot Screen Separation

Photo

Colored Text Separation

A269D078.WMF

(1) Edge separation

The edges of text and line diagram elements are identified by using the characteristics of strong contrast, continuity of black or color pixels, and continuity of white pixels around the black or color pixels.

The machine does this by only referring to the green signal.

(2) Dot screen separation

Dot screen areas are separated from non-dot screen areas (mainly text). The machine determines that if white pixels are not detected around the non-white pixels, it is a dot screen area.

The machine does this by only referring to the green signal.

(3) Colored text separation

Black pixels and color pixels in text areas are identified by determining the difference among the RGB maximum signal levels and the output levels of the RGB video signals.

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Filtering and Color Conversion

A269D079.WMF

A269D080.WMF

RGB Smoothing Filter

Depending on the results of auto text/photo separation (or depending on the selected original mode), the appropriate software filters are applied to the RGB video signals. The RGB smoothing filter is applied to photo areas; an edge emphasis filter is applied to text areas.

Color Conversion

A matrix converts the RGB video signals from each scanning cycle into YMCK video signals. The content of the matrix depends on the selected mode. The transparency for each color toner is not ideal, as shown above. Color conversion compensates for the difference between ideal and actual characteristics.

The following modes affect the matrix: color conversion mode (this is a user mode, not to be confused with the color

A269D081.WMF

conversion process described in this section), pastel mode, color balance mode, original mode (press print glossy photo, 2nd generation), RGB toner correction mode

The following color conversion table is an example of the results from the matrix operation, for simple color copying without any special modes applied. For example, to represent green, the yellow and cyan toners are used in a proportion of 1:1.

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30 March, 1999 IMAGE PROCESSING

Original Color

Toner

Y 11110000 M 11000110 C 10011100 K 10000000

KRYGCBMW

Color Conversion Table

If the user selects a special mode some of the values in this table may be between 0 and 1. The following page briefly explains the effects of some modes.

Color Conversion mode

Color conversion mode is a user feature, not to be confused with color conversion (RGB to CMYK) described above. In color conversion mode, a selected color (C/M/Y/R/G/B/K/W) on an original that falls within the recognized thresholds for that color is converted into a different color on the copy. Up to 4 colors can be converted at one time. (Please refer to the operator's manual for details.)

For example, when changing Yellow to Black, the coefficients for the Yellow video signal in the color conversion table become: Y: 1, M: 1, C: 1, K: 1

Pastel mode

In pastel mode, the matrix parameters change, and the output of the combined YMCK data shifts to a value between 100 % and 25 %. There are 9 steps, and the value used depends on the user's selection.

Detailed

Descriptions

Color balance mode

In color balance mode, the data output for each color (YMCK) can be changed independently by changing the matrix parameters. Three are nine possible values for each color.

Original mode

There are three modes within photo mode (Press Print, Glossy Photo, and 2nd Generation) and three types of special original mode (Marker Pen, Inkjet, Map). The machine selects the most suitable matrix for the original type that is selected by the user at the operation panel.

For inkjet mode, the user can select one of three different inkjet gamma (γ) tables to emulate the output of three different types of inkjet printer. (This is done with the User Tools.)

RGB toner correction mode

Two color toners are used on R, G, and B output in the single color mode. The toner mixing ratios for R, G, and B are adjustable (SP 5-611-001 to 5-611-006). The adjustments are valid for two-toner single-color (R, G, or B) copy modes only.

Twin color mode

Twin color mode separates black part area and colored areas. The machine then converts black to one color (that was selected by the user) and all the color areas another color (the output has only two colors). (Refer to the operator's manual for details.)

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Background Density Control and ADS

A269D084.WMF

A269D083.WMF

A269D085.WMF

Background density control

This function removes low ID image signals (background) that are less than a certain threshold. The threshold that is applied depends on the color mode (single color or full color). For each of these modes, the user can select a different threshold.

ADS (Auto Image Density Selection)

In ADS, the user does not set the threshold; the machine calculates it, guided by input from the user for F/C and 2C mode.

In full color mode, after scanning the machine calculates the threshold for removing background by referring to the RGB data taken from the entire original.

In black and white mode, the machine detects the background level for the original, also known as the peak white level, and removes this from the image, to make a white background. Peak level data is taken for each scan line to correct for changes in background density down the page. From the peak white level, the machine determines the white reference value for A/D conversion. Therefore, in black and white mode the background density is controlled before data is input to the A/D converter.

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UCR (Under Color Removal)

A269D086.WMF

Obtaining the right colors using YMC toner addition does not always work perfectly. For example, if the same quantity of toner for each color (YMC) is put on the paper, ideally the image should become black, but in reality it becomes a dark color, such as dark blue.

To compensate for this, an equal portion of the common ID value for each color is subtracted. This reduces the amount of color toner on the paper, and a proportional amount of black toner is added. This process is known as UCR.

Detailed

Descriptions

The UCR ratio is the percentage of the common ID value for YMC that is subtracted and converted to black. In the above example, where the UCR ratio is 100%; the entire common ID value is subtracted from Y, M, and C, and converted to K.

In actual use, the UCR ratio depends on the color mode and the image density. For example, when the UCR ratio is 95%, 95% of the entire common ID value is subtracted from Y, M, and C, and converted to K.

The UCR ratio can be adjusted by the user during initial setup.

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IMAGE PROCESSING 30 March, 1999

Magnification Processing

Main Scan Magnification

A269D088.WMF

The machine changes the scanner speed to reduce or enlarge the original in the sub-scan direction. However, an LSI on the IPU Board handles reduction and enlargement in the main scan direction.

Scanning and laser writing are done at a fixed pitch (the CCD elements cannot be squeezed or expanded). So, to reduce or enlarge an image, imaginary points are calculated that would correspond to a physical enlargement or reduction of the image. The correct image density is then calculated for each of the imaginary points based on the image data for the nearest two true points. The calculated image data then becomes the new (reduced or enlarged) image data.

NOTE:

The actual calculations for main scan magnification use the polynomial convolution method. This mathematical process is beyond the scope of a service manual and will not be covered here.

400 dpi to 600 dpi Conversion

The copier converts image data that is scanned at 400 dpi to 600 dpi by performing the same processing that is explained above in “Main Scan Magnification” by applying 150% magnification processing on the image data for both main and sub scans.

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Image Creation

These are some of the user selectable image processing functions.

Mirror Image

This function generates a mirror image of the original by inverting the original image in the main scan direction.

A269D951.WMF

Slanted Image

This function generates a slanted image of the original by shifting the original image in the main scan direction by a specified angle. The maximum allowable angle is

±45°

+10

Detailed

Descriptions

–45

Image area

This area is not printed.

Repeat Image

The copier can copy a specified area of the original repeatedly over the entire page. There are three ways of specifying the copy area. (Refer to the operator's manual for details.)

1) Entering length.

2) Entering the number of images

3) Entering via an editor

+45

A269D952.WMF

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IMAGE PROCESSING 30 March, 1999

Outline Image

The copier converts the image data into binary-value data and submits the converted data into an outline image filter. The frame width may be set to 0.25, 0.5, or 0.75 mm.

Shadow Image

The shadow is cast in the lower right direction from the original at an angle of 45 degrees. The shadow may be plane or solid and the shadow color may be the same color or specified color.

Input

Outline image filter

A269D953.WMF

Outline image output

To produce a half tone of the same color, the copier identifies the color of the original and uses that color for shading.

The color may be specified from the editor (K, C, M, Y). The width of the shadow can be specified between 1 mm and 4 mm in 1 mm units. The copier does not allow the user to specify the color of the shadow when performing both outline imaging and shadowing.

Positive-Negative (Image Inversion)

The copier converts the colors of the full-color original to their complementary colors in the inversion mode.

W to K B to Y G to M R to C

A269D954.WMF

û û

The user may specify the area and magnification ra tio.

A269D955.WMF

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Gradation Processing

Gamma (

A269D089.WMF

KCMY

γγγγ

) Correction (Printer

[Fig. 1]

γγγγ

)

[Fig. 2]

A269D090.WMF

Ideally, the gamma curves for Yellow, Magenta, Cyan, and Black are identical, as shown in figure 1. However, they are not because electrical components always vary slightly, resulting in varying gamma curves, as shown in figure 2.

Detailed

Descriptions

The Auto Color Calibration (ACC) procedure can compensate for any discrepancies in color reproduction. ACC makes new gamma curves for each color in each mode (text, photo, black text). After ACC, the gamma curve for each color can be adjusted with service programs (SP4-910 to SP4-926).

Using these programs, each gamma curve can be adjusted for 4 different modes: ID max., High ID, Middle ID, and Low ID, as shown on the following page. If the previous gamma curve was better, it can be recalled. Alternatively, the factory settings can be loaded using SP 5-610-004. In addition, the factory settings can be overwritten by the current gamma settings using SP5-610-005. SP7-904 prints the current manual γ settings.

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IMAGE PROCESSING 30 March, 1999

ID max.

This mode adjusts the total image density level as shown in figure 3.

Shadow (High ID)

The High ID mode adjusts the image density between Level 6 and Level 9 of the color gradation scale on the C-4 test chart (figure 4).

Middle (Middle ID)

The Middle ID mode adjusts the image density between Level 3 and Level 7 of the color gradation scale on the C-4 test chart (figure 5).

[Fig. 3]

[Fig. 4]

A269D091.WMF

A269D092.WMF

Highlight (Low ID)

The Low ID mode adjusts the image density between Level 2 and Level 5 of the color gradation scale on the C-4 test chart (figure

6).

2-50

[Fig. 5]

[Fig. 6]

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30 March, 1999 IMAGE PROCESSING

Auto Color Calibration Test Pattern

The copier firmware has a test patt ern that has eight 17-step gradation scales for each color (KCMY), including background white, for Text and Photo modes.

Dark Light

Auto color calibration

This machine automatically calib rates the printer gamma (γ) curve when the

user selects ACC.

When ACC is activated, the m achine prints out an ACC Test Pattern. The user puts the test pattern on the exposure glass, then the machine scans the test pattern. The machine scans eight lines, one for each color (KCMY) in text mode, and one for each color in

K C M

photo mode.

Detailed

Descriptions

The machine corrects the printer gamma by comparing the ideal settings with the current image density. Then the machine combines the corrected

A269D095.WMF

gamma curve with the High, Middle, and Low ID values currently in memory (these are not reset to the defaults first, as in some earlier models)

The machine the calculates the ID max (amplitude of the gamma curve) based on data from the ACC scan.

The corrected printer gamma curves can be adjusted further using SP modes (SP4-910 to SP4-926).

ACC tar g et:

This copier allows adjustments in 10 steps on the target base γ to be used during auto color correction.

(SP4-501-001 through SP4-501-008: For the copier)

(SP4-502-001 through SP4-502-008: For the printer) Default: 5 Adjustable range: 0 to 10

NOTE:

The adjustable range is 0 to 50. However, the effective range is 0 to 10. Even when it is set to 50, it is the same level for 10.

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Dither Processing

This copier provides 256 gradations by using 1 dot by 1 dot and 2 dots by 2 dots dither patterns in each of the text and photo modes, whereby ensuring high image quality. In the printer mode, the copier uses a different table for photo mode dithering from that for the copier.

A269D096.WMF

A269D097.WMF

Area Manipulation Functions

In an edit model, the image data in the areas that are specified from the operation panel and that are subject to pre-scanning are encoded in the area processor section and sent to the image processor section together with the main scan image data. The data in each area (20 areas maximum) is subject to color correction in the "color calibration 2" step of the IPU board.

The edit version of the copiers is also equipped with a composition capability.

CPU

The copier incorporates a 32-bit CPU to process and control the timing of the data in the scanner and IPU sections.

IPU Board Test

The IPU consists of some LSI chips, DRAM, SRAM, and a controller block that controls these chips and RAM. They are interconnected in a way that allows IPU board tests to be run from SP mode (SP4-904-001 and SP4-094-002) and check for IPU malfunctions (ASIC diagnostics on the shading and subsequent stages).

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30 March, 1999 LASER EXPOSURE

2.5 LASER EXPOSURE

2.5.1 OVERVIEW

13 12

Detailed

Descriptions

5 6

A269D102.WMF

1. LD control board

2. LD unit

3. Cylindrical lens

4. 1st fθ lens

5. 2nd fθ lens

6. Polygon mirror

7. Polygon motor drive board

8. Laser synchronization detector

9. Polygon mirror motor

10. OPC drum

11. Toner shield glass

12. Drum mirror

13. Laser synchronization detector mirror

14. BTL

This machine uses laser diodes to produc e elec trostatic images on an OPC drum. The laser diode unit converts image data from the LD main control board into laser pulses, and the optical components direct these pulses to the drum.

For main scanning, this copier uses a polygon mirror that rotates at 23,622 rpm. The drum rotation (with a peripheral velocity of 200 mm/s) controls sub-scanning. The copier achieves 256 gradations using a combination of laser power modulation (PM) and pulse width modulation (PWM). The laser diode unit is a multi-beam type with two laser diodes and supports laser exposure at 600 dpi.

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LASER EXPOSURE 30 March, 1999

2.5.2 LD UNIT

LD Safety Switch

Front Door Safety SW

Video Control Board

CN601-4

CN603-23 ~ 27

CN601-3

CN600-1

+5V

PSU

LDDR

CN650-24 ~ 28

LD2 LD1

LD LDPD PD

LD Drive ICLD Drive IC

A269D250.WMF

The front door has two safety switches that ensure that the laser beam does not accidentally switch on during servicing, while the front door is open. These safety switches are installed in series on the 5V line between the PSU and the LD unit. When the front door is opened, the door switches cut off the 5V line to the LD unit.

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LD Unit Configuration

The LD unit is a 2LD multi-beam type. It consists of two laser diodes [A], two collimate lenses [B], two apertures [C], a composite prism [D], and an LD control board [E]. The beams from the laser diodes are converted to parallel beams by the collimate lenses. The apertures then form the laser beams to the diameter necessary for writing on the drum. The two laser beams are output in parallel

42.3 µm apart through the composite prism. Two lines are written simultaneously on the drum. This provides printing at 600 dpi (sub-scan).

The wavelength of the semiconductor laser diodes is 780 nm and the maximum output power is 15 mW.

LD2

LD1

[D]

LD1

LD2

2 mm

42.3 µm

A269D103.WMF

Detailed

Descriptions

[A]

[C]

A269D512.WMF

[B]

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Auto Power Control (APC)

LD5V

VIDEO

LEVEL

LD OFF

Current

Control

LD Drive Board

A259D501.WMF

Even if a constant electric current is applied to the laser diode, the intensity of the output light changes with the temperature. The intensity of the output decreases as the temperature increases.

In order to keep the output level constant, the output light intensity is monitored through a photodiode (PD) enclosed in the laser diode. The photodiode passes an electrical current that is proportional to the light intensity. The output is not affected by temperature, so it faithfully reflects the changes in the LD output, without adding anything itself.

Just after the main switch is turned on, the current control IC on the LD drive board excites the laser diode at full power (power level 32) and stores the output of the photodiode as a reference. The current control IC monitors the current passing through the photodiode. Then it increases or decreases the current to the laser diode as necessary, comparing it with the reference level. Such auto power control is done during printing while the laser diode is active.

The laser power level is adjusted on the production line. Do NOT touch the variable resistors on the LD unit in the field.

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