OKI B410, B420, B430 Schematic

B410/B420/B430/MPS420b

Maintenance Manual

080409B

Oki Data CONFIDENTIAL

Copyright © 2008 by Oki Data. All Rights Reserved

Oki Data America's, Inc. ("Oki Data"), authorizes you to view, copy, and print
documents published by Oki Data for noncommercial use within your organization only.
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proprietary notification relating to that individual document.

Nothing contained herein shall be construed as conferring by estoppel, implication or
otherwise any license or right under any patent or trademark of Oki Data, Oki Electric
Industry Co., Ltd. ("Oki Electric"), or any third party. Except as provided above nothing
contained herein shall be construed as conferring any license or right under any Oki
Data copyright.

Oki Data has taken care to insure that the information which follows is complete,
accurate and up-to-date. However, Oki Data assumes no responsibility for errors or
omissions which may occur. All the information provided is subj ect to change from time
to time at the sole discretion of Oki Data.

All publications may include technical inaccuracies or typographical errors. We reserve
the right to make periodic changes, additions, and deletions to publications without
notice.

The most up-to-date drivers and manuals are available from the web site:

http://www.okiprintingsolutions.com

Oki Data CONFIDENTIAL

This Maintenance Manual describes the maintenance methods in the printer field for the maintenance
personnel. In addition, regarding the handling and operating method of the printer, please refer to the "User’
s Manual".
The differences between various types of printers described in this Maintenance Manual are as follows.

PREFACE

PREFACE

B410d B410dn B420dn B430d B430dn

Engine speed (letter/A4)

Resolution

Emulation

Max.

resolution

Standard

Option

LCD

Operation

panel

display
Switch

LED lights

Input tray (Manual/Auto)

Input tray (1st bin)

Maximum Input capacity

USB 2.0

Interface

Parallel

Ethernet

Auto Duplex

Monthly Duty

Cycle

Maximum

Toner life@ISO19752

Dimensions

(inch./mm)

Width
Depth

Height

ODA 100v

ODA 200v

Sales

Territories

OEL
AOS 1byte
AOS 2byte

Japan
China

30/28 30/28 30/28 30/28 30/28

2400 x 600

dpi

PCL6/SIDM PCL6/SIDM PCL6/SIDM

N/A N/A N/A N/A N/A N/A

16 character x 2 16 character x 2 16 character x 2 16 character x 2 16 character x 2 16 character x

1 (online/

offline)

2 2 2 2 2 2

Single sheet
manual feed

250 sheets 250 sheets 530 sheets 250 sheets 250 sheets 530 sheets

781 781 1110 830 830 1110

N/A N/A

Standard Standard Standard Standard Standard Standard

50,000 pages 50,000 pages 70,000 pages 70,000 pages 70,000 pages 70,000 pages

3,500

14.5”/369mm 14.5”/369mm 14.5”/369mm 14.5”/369mm 14.5”/369mm

15.6"/395mm 15.6"/395mm 15.6"/395mm 15.6"/395mm 15.6"/395mm

10.6"/268mm 10.6"/268mm 11.7"/297mm 10.6"/268mm 10.6"/268mm

N/A N/A N/A

TBD TBD TBD TBD TBD

2400 x 600

dpi

1 (online/

offline)

Single sheet
manual feed

3,500 (7,000

available for

JPN only)

2400 x 600

dpi

6 6 6 6

50 sheets

Multi Purpose

Feeder

3,500/7,000/

10,000

N/A
N/A
N/A

1200 x 1200

dpi

PCL6/PS3/

SIDM

50 sheets

Multi Purpose

Feeder

3,500/7,000 3,500/7,000

N/
N/A

1200 x 1200

dpi

PCL6/PS3/

SIDM

50 sheets

Multi Purpose

Feeder

dp

PCL6/PS3/

SIDM

2

50 sheets

Multi Purpose

Feeder

3,500/7,000/

10,000

Note!

• It is prohibited to reprint entire or partial of the content without prior consent.

• For the reason of printer improving and manual content revising, the content of this
maintenance manual may change without any warning in the future.

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1. CONFIGURATION ........................................................................................................7

1.1 System Configuration ............................................................................................................................7

1.2 Printer Configuration ..............................................................................................................................8

1.3 Optional Configuration ..........................................................................................................................11

1.4 Specification .........................................................................................................................................12

1.5 Printing display .....................................................................................................................................15

1.5.1 VCCI label, Serial No. label ............................................................................................................15

1.5.2 Warning label ..................................................................................................................................15

1.5.3 Warning / Caution display ...............................................................................................................16

2. Operational explanation .............................................................................................17

2.1 Electrophotographic process mechanism ............................................................................................17

2.2 Printing process ....................................................................................................................................24

2.3 Toner entrance detection ......................................................................................................................28

Contents

Contents

3. Parts replacement ......................................................................................................30

3.1 Preparation for parts replacement ........................................................................................................30

3.2 Parts layout ...........................................................................................................................................32

3.3 Parts replacement method ...................................................................................................................37

3.3.1 LED Head .......................................................................................................................................38

3.3.2 Roller-Transfer ................................................................................................................................39

3.3.3 Cover-Side-R ..................................................................................................................................40

3.3.4 Cover-Side-L ..................................................................................................................................41

3.3.5 CU Board ........................................................................................................................................42

3.3.6 Motor-DC-Main ..............................................................................................................................43

3.3.7 OPE Cover-Assy ............................................................................................................................44

3.3.8 Ope-Board ......................................................................................................................................45

3.3.9 MPT-Assy (In case of B410dn, it is Manual-Assy) ..........................................................................46

3.3.10 Front-Guide-Assy .........................................................................................................................47

3.3.11 Roller-Assy-Feed ..........................................................................................................................48

3.3.12 Guide-Paper-Duplex .....................................................................................................................49

3.3.13 Stacker-Cover-Assy ......................................................................................................................50

3.3.14 Fuser-Assy ...................................................................................................................................51

3.3.15 Rear-Cover-Assy ..........................................................................................................................53

3.3.16 Frame-Assy-Lower .......................................................................................................................54

3.3.17 High voltage / Low voltage power board .......................................................................................56

3.3.18 Plate-Bracket-Motor ......................................................................................................................57

3.3.19 Roller-Back up ..............................................................................................................................58

3.3.20 Roller-Resist .................................................................................................................................59

3.3.21 Lever-In-Sensor ............................................................................................................................60

3.2.22 Lever-Eject-Sensor/Photo-Interrupter ...........................................................................................61

3.3.23 Lever-End/Lever-Duplex/Lever-Cassette/Gear-Assy-Clatch ........................................................62

3.3.24 Paper feeding roller (Roller-Pick-Up,Roller-Feed-NOW,Roller-Assy-MPT) ..................................64

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4. ADJUSTMENT ...........................................................................................................66

4.1 Category and function of maintenance mode .......................................................................................66

4.4.1 User maintenance mode (Administrator Menu) .............................................................................66

4.1.2 System maintenance mode (System maintenance menu) .............................................................71

4.1.3 Engine maintenance mode .............................................................................................................76

4.1.4 Environment mode setting ..............................................................................................................84

4.1.5 EEPROM Initialization ....................................................................................................................85

4.2 Adjustment at part replacement ...........................................................................................................86

4.2.1 EEPROM data upload / download method .....................................................................................86

5. Periodic Maintenance .................................................................................................87

5.1 Periodic Replacement Parts .................................................................................................................87

5.2 Cleaning ...............................................................................................................................................87

5.2.1 Cleaning of LED lens array .............................................................................................................87

5.2.2 Cleaning Page Function .................................................................................................................89

6. Procedures for Repairing ...........................................................................................90

6.1 Troubleshooting ....................................................................................................................................90

6.2 Points to be checked before modifying printing problems. ....................................................................90

6.3 Points to be checked when the printing problems are modified ...........................................................90

6.4 Preparation for Troubleshooting ............................................................................................................90

6.5 Troubleshooting Flow ............................................................................................................................91

6.5.1 LCD Status Message/ Trouble Table ...............................................................................................91

6.5.2 LCD Message Troubleshooting.....................................................................................................103

6.5.3 Print Troubleshooting ....................................................................................................................111

Contents

7. Connection Diagram .................................................................................................119

7.1 Connection diagram ...........................................................................................................................119

7.2 Board Layout ......................................................................................................................................120

7.3 Resistance value ................................................................................................................................134

Appendix A Centronics Parallel Interface .....................................................................136

Appendix B USB Interface ...........................................................................................143

Appendix C Maintenance Manual for Second Tray unit ................................................145

1 Overview................................................................................................................................................145

1.1 Function ...........................................................................................................................................145

1.2 Exterior and Parts Name .................................................................................................................145

2. Description for Operation of Second Tray unit ......................................................................................146

3. Part Replacement .................................................................................................................................147

3.1 Precautions on replacing parts ........................................................................................................147

3.2 Arrangement of Parts ......................................................................................................................148

3.3 How to Replace Parts ......................................................................................................................149

3.3.1 Roller-Pick-Up, Roller-Feed-Now .............................................................................................150

3.3.2 Guard-Connector. Connector (9715S-08Z02-G4C) ..................................................................151

3.3.3 Roller-Feed ...............................................................................................................................152

3.3.4 Board-OT7 ................................................................................................................................153

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3.3.5 CONN Cord-AMP8P-AMP8P ...................................................................................................154

3.3.6 Gear-Assy-Clatch .....................................................................................................................155

3.3.7 Frame-Assy-Retard, Spring-Retard ..........................................................................................157

4. Cleaning of Paper Feed Roller and Separation Roller ..........................................................................158

5. Procedure for Troubleshooting ..............................................................................................................159

5.1 Precautions for Troubleshooting ......................................................................................................159

5.2 Preparation before Troubleshooting .................................................................................................159

5.3 Troubleshooting Method ..................................................................................................................160

5.3.1 LCD Status Message List .........................................................................................................161

6. Connection Diagram .............................................................................................................................163

6.1 Connection diagram ........................................................................................................................163

6.2 Board Arrangement .........................................................................................................................163

Appendix D Network Interface .....................................................................................165

Contents

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1.1 System Configuration

As the diagram 1.1 shows, for the standard configuration printer is configured by controller unit and
engine unit.

1. CONFIGURATION

1. CONFIGURATION

2nd tray unit*

Main DC Motor

LAN

(10BASE-T/100BASE-TX)

USB 2.0

Register clutch

Hopping clutch (1st)

Hopping clutch (MPT)

Solenoid for paper inverting

Main print circuit board

Paper end sensor

Cassette & Duplex detecting

Exit sensor

Rear cover open sensor

Fuser unit

Halogen lamp

Low voltage

power supply unit

FUSE

Temperature sensor

AC-SW

AC inlet

CENTRONICS

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LCD:1, LED:2, SW:6

Operator panel board

LCD:1, LED:2, SW:1(B410d/B410dn)

LED head

(B420dn/B430d/B430dn)

Tag board

Toner cartridge

Tag transit board 3

Image drum cartridge

Figure1-1

Transfer roller

sensor

Toner inlet

WRT

sensor

Stacker cover open SW

High voltage power supply uint

IN

Tag transit board 1

Tag transit board 2

sensor

FAN

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Oki Data CONFIDENTIAL

A

A

A’

Paper cassette

Toner cartridge

High voltage
power board

Low voltage
power board

Image drum cartridge

A’

Stacker-Cover-Assy

Cover-Side-R

Cover-Side-L

Plate-Base-PCB

Plate-Assy-Base

Motor-Fan

Duplex

Rear-Cover-Assy

Fuser-Assy

OPE Cover-Assy

Guide-Paper-Duplex

Guide-Paper-R

Manual-Assy

Front-Guide-Assy

CU board

1.2 Printer Configuration

The printer main unit includes the following hardware parts.

• Electrophotographic processing part

• Paper feeding part

• Controller

• Op

erational part

• Power supply unit

•

Note!

The configuration of printer main unit is shown as diagram 1-2~1-4

B410d/B410dn

Fuser-Assy has to be replaced by Assy unit.

• It is forbidden to disassemble Fuser-Assy or reuse the disassembled Fuser-Assy.

1. CONFIGURATION

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Figure1-2

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Oki Data CONFIDENTIAL

A

A

A’

A’

Stacker-Cover-Assy

Cover-Side-R

Cover-Side-L

Plate-Base-PCB

Plate-Assy-Base

Motor-Fan

Duplex

Rear-Cover-Assy

Fuser-Assy

OPE Cover-Assy

Guide-Paper-Duplex

Guide-Paper-R

MPT-Assy

Front-Guide-Assy

CU board

Paper cassette

Toner cartridge

High voltage
power board

Low voltage
power board

Image drum cartridge

B430d/B430dn

1. CONFIGURATION

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Figure1-3

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Oki Data CONFIDENTIAL

B420dn

1. CONFIGURATION

Stacker-Cover-Assy

Cover-Side-R

Rear-Cover-Assy

Duplex

Cover-Side-L

Toner cartridge

Motor-Fan

A’

Fuser-Assy

Low voltage
power board

A’

High voltage
power board

A

Guide-Paper-Duplex

Plate-Base-PCB

Plate-Assy-Base

CU board

A

OPE Cover-Assy

MPT-Assy

Guide-Paper-R

Front-Guide-Assy

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Image drum cartridge

　Rev.1

Paper cassette

Figure1-4

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Oki Data CONFIDENTIAL

1.3 Optional Configuration

The options attached to the printer are as follows. These options can be ordered respectively for the
printer main unit.

(1) Second tray unit

1. CONFIGURATION

(2) Additionally installed memory (Domestic oriented printer only use 128MB.)

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Oki Data CONFIDENTIAL

1.4 Specification

(1) Type Desktop
(2) Dimension 268mm (Height) x 369mm (Width) x 395 (Depth)

:B41
297mm (Height) x 369mm (Width) x 395mm (Depth)
:B42

(3) Weight Approx. 10.6kg ( Including printer main unit & consumables.
Options, Feeding quantity of paper are excluded.)

1. CONFIGURATION

0d/B410dn/B430dn

0dn

(4) Development met

hod Dray type – Element developing method
Exposure method LED Head method
(5) Paper type, thickness, Size

Recommended paper Normal paper………….Excellent white A4
OHP Sheet…………….Sumitomo 3M CG3300
Label paper…………….Kokuyo LBP-A693

Category Size unit: mm (inch) Thickness

A4 Weig
A5
A6
B5

Letter

Normal Paper

Postcard

Envelope

Legal
Legal

Statement

Executive

h86~215.9

idt

Custom

Postcard Postcard

etu

rn Postcard

R

lope 1 (Chou #3) The envelope should be using 85g/m paper. The

Enve

lope 2 (Chou #4)

Enve

Envelope 3 (You #4)

W

Length 140~355.6

ht 55~105kg(64~120g/m2)

For double-side printing, weight55~90kg

2

(64~105g/m

Tray 1, Width 100~215.9, Length 210~355.6
Tray 2, Width 148~215.9, Length 210~355.6

flap of the envelope Chou type should not be with
fold, the flap of the envelope you should be clearly
folded.

The envelope should be using 24 lb. paper and
the flap part of it should be clearly folded.

)

Label Paper

OHP Sh

Part

ial Printing
Paper

Paper for Color

Printing

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　Rev.1

Widt

Custom

Letter

Letter

h86~215.9

Length 140~355.6

ht 55~105kg(64~120g/m2)

Weig

Weight 55~105kg(64~120g/m

2

)

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Oki Data CONFIDENTIAL

(6) Paper feeding method / Ejecting method

Type Size

5

A5 *

5

B5 *
Executive *

Statement *

A4

Normal
paper

Postcard

5

*

Envelope

5

*

Label
paper

OHP A4/Letter

Letter
Legal (13 inch)
Lega (14 inch)

A6 *

Custom *3 *
Width 86~215.9mm
Length
140~355.6mm

Postcard/
Return postcard

Envelope1 (CHOU
3
Envelope2
4
Envelope3
Com-9
Com-10
DL
C5
C6
Monarch

Custom
Width 86~215.9mm
Length
140~355.6mm

A4/Letter

5

5

5

5

)

)

CHOU

(

(YOU 4

Thickness

Weight

(

Weight
55~105kg

Weight
55~105kg

Weight
55~90kg

Weight
91~105kg

Weight
55~105kg

Weight
55~90kg

Weight
91~105kg

Postcard
or less
than
weight
135kg

)

6

*

6

*

0.1~

0.5mm

0.1~

0.5mm

Kg)

:

Tray

feeding Method

Paper

cassette

Tray

1

*

Paper

Multipurpose

2

4

tray *

1

Manual

Paper

ejecting

method

Face

up

Face

down

○

× :

△

double-side print *

Tray

Tray

1

1. CONFIGURATION

It is possible to use it.

:

It is not possible to use it.
It is possible to use it by a part of size

:

Double-side print

Automatic

Multipurpose

2

4

*

tray*

2

1

Manual Tray

1

Manual

double-side print

Multipurpose

Tray

2

4

*

tray *

1

Manual

*1: Multipurpose tray can be used for B420dn/B430dn.

2

*

: Face-up paper ejecting is not available at automatic double-side printing.

3

*

: Tray 1 is as width 100~21539mm, length 210~355.6mm. Tray 2 is as width 148~215.99mm, length 210~355.6mm.

4

*

: Tray 2 (The second tray unit) is for option.

5

*

: In case to set up the paper size for A5, A6, Postcard, Envelope, if the width of B5, Executive, Statement, Normal paper is less

than 200mm, also if thick paper or thicker paper has been set up for the paper thickness, the printing speed changes to be
slowly.

6

: • Envelope CHOU should be made by the paper or basis weight of 85g/m2 and without any fold on the flap part.

*

• Envelope YOU should be made by the paper of basis weight of 85g/m2 and with clear fold on the flap part.

• Com-9, Com-10, Monarch, C5, C6, and DL should be the envelope using 24lb paper and with clear fold on the flap part.

(7) Printing speed Continuous printing : Maximum 28 piece/second (A4, At copy mode, First try)

For Envelope • Postcard, if to enhance the printing quality, the
printing speed changes to be decreased.

For the resolution degree of 600 x 2400, if to enhance the

printing quality, the printing speed changes to be decreased.

W

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　Rev.1

arm up time : Approx. 25 second (25°C, 100V)

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Oki Data CONFIDENTIAL

10

28

32

Temperature (°C)

20 80

Relative humidity (%)

Up and running

(8) Paper feeding method Automatic feeding
(9) Paper ejecting method Face down (Rear ejecting) / Face up (Front ejecting)
(10) Resolution (Max.) 2400 × 600 dots / inch (B410d/B410dn/B420dn)

1200 × 1200 dots / inch (B430d/B430dn)
(11) Input electricity AC100V ± 10V, 50/60Hz ± 1Hz(B410dn/B430dn)

(12) Electricity consumption Up and running: Maximum 800W, Average 450W (25°C)
Ready and waiting: Average 70W (25°C)
Power-saving mode: (Without option) Under 6W
(With option) Maximum 7W
(13) Temperature and Humidity

1. CONFIGURATION

Tenperature Humidity

Up and
running

Power switch

off

Keeping

10~32

0~43

-10~43

20~80%RH (Relative Humidity) No condensation.
However, Maximum temperature of wet ball should
be 25°C.

10~90%RH (Relative Temperature) No
condensation. However, Maximum temperature of
wet ball should be 26.8°C.

10~90%RH (Relative Humidity) No condensation.
However, Maximum temperature of wet ball should
be 26.8°C.

(14) Operating noise In Printing : Rage A based on JIS Z9831, Average below 53dBA for SLOW.
Ready and waiting : Rage A based on JIS Z9831, Average below 53dBA for SLOW.
At power save : No sound (Background level)

(15) Consumables Toner cartridge : Approx. 3,500 piece /Approx. 7,000 piece/Approx. 10,000

printing paten. But, except the 1st Toner cartridge)
Imag

Cartridge : Approx. 20,000 piece (Single-side 3 pages/job) At Power save off.
Approx. 12,000 piece (Single-side 1 page/job) At Power save off.

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piece(A4 ISO/IEC 19752 Continuous printing as

e drum : Approx. 25,000 piece (Continuously single-side printing of A4)

Approx. 7,000 piece (Single-side 1 page/job) At Power save on
(Minimum value)

.

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Oki Data CONFIDENTIAL

Serial No.

Made In China

B430dn

B410dn

1.5 Printing display

1.5.1 VCCI label, Serial No. label

The VCCI label and Serial No. label have been attached on the specified part of printer as shows
below.

1. CONFIGURATION

1.5.2 Warning label

Warning label has been attached on the part of printer that may cause injury to the operator.
Maintenance must be performed following the indication of the warning label.

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Oki Data CONFIDENTIAL

Low voltage power board

Warning / Caution content record

Heat sink

Transformer

High voltage power board

1.5.3 Warning / Caution display

The following warning / caution are displayed on the electrical power / sensor board.

1. CONFIGURATION

Note!

•

•

There is a risk of electric shock in the middle of the heat sink and transformer. Be sure to check

before touch it.
It may happen that the electricity has still left on the electrical circuit even after the fuse opened.

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Oki Data CONFIDENTIAL

2.1 Electrophotographic process mechanism

(1) Electrophotographic process
The following describes the overview of electrophotographic process.

1. Charging

Equ

2. Exposure

The l

3. Development

Neg

ally charge the surface of image drum by applying negative voltage to the charged roller due to

negative charge.

ight from LED Head is exposed on the negative-charged surface of image drum. The surface
electrical potential of the exposed part of image drum surface becomes lower. Then forms electrostatic
latent image.

ative-charged toner is attracted to the electrostatic latent image due to electrostatic while touching

the image drum. Then forms viewable image.

2. Operational explanation

2. Operational explanation

4. Transfer

Ove

5. Drum cleaning

The remaining toner on the image drum that is not transferred is made to be equable by cleaning roller.

6. Fusing

The t

rlap paper on the surface of OPC drum, from the backside of paper transfer toner image to the

paper by applying electrical charge by transfer roller.

And is temporarily attracted to the cleaning roller due to electrostatic.

oner image that is transferred to paper is fused on paper by heat and pressure.

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Oki Data CONFIDENTIAL

Image drum

Charged roller

Power

Charged roller

LED head

LED head

Image drum

Image drum

Paper

Power

1. Charging

Cha

rge the image drum surface by applying voltage to the charged roller that contacts the image drum

surface.

2. Operational explanation

2. Exposure

The light emitting from the LED Head will be exposed to the negative charged image drum. When the

surface electric potential of exposed part of the image drum goes to decrease, the electrostatic latent
image complying with image signal is formed.

Image drum is coated by basic layer (UL), charge generating layer (CGL), charge transferring layer (CTL)

on the basic material aluminum. The thickness of the organic light sensor (OPC) that is consisted by
CTL and CGL is approximate 20µm.

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Oki Data CONFIDENTIAL

Image drum

Charged roller

Image developing plate

Toner supply roller

Image
developing
roller

3. Image development

Toner is attracted to the electrostatic latent image on the image drum surface, then the electrostatic

latent image changes to toner image.

1 As the roller on the supply spot of toner rotates while scrubbing the image-developing roller,

2. Operational explanation

fiction electricity occurs between the image developing roller and toner; toner is attracted to
the image-developing roller.

2. The toner that has been attracted to the image-developing roller is dropped down to the
developing plate to make a thin toner film on the image developing roller side.

3 The toner is attracted by the exposed part (Low electrical potential part) of the image drum

when the image drum contact the image developing roller, so as to see the electrostatic latent
image.

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Oki Data CONFIDENTIAL

Image drum

Basic material

Toner feeding roller

While the cover is closed it will be
connected and bias will be applied.

Image developing roller

2. Operational explanation

Note! The ne

and image developing roller as show below.

cessary bypass voltage in image processing is impressed on the toner feeding roller

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Oki Data CONFIDENTIAL

Image drum

Transfer roller

Paper

Power

4. Transfer

Th

As high plus voltage is applied to transfer roller from the power supply, the plus charge on the transfer

e transfer roller, which is from conductive sponge material, is created to meet intimate attachment
of image drum roller surface and feeding paper. The feeding paper is set up on the surface of image
drum. Plus charge, which is the converse polarity with toner polarity, is applied from the backside of the
paper.

roller surface is induced and transferred to the paper while the paper contact the transfer roller. The
negative charged toner, which has been attracted to the image drum surface, is transferred to the
surface of feeding paper by the plus charge of the backside of the paper.

2. Operational explanation

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Oki Data CONFIDENTIAL

Power supply

Cleaning roller

Image drum

Transferring roller

5. Drum cleaning
1 Cleaning

After the completion of transferring, the remaining toner on the image drum is temporarily attracted
by the electrostatic and the image drum surface is cleaned.

2. Operational explanation

2 Roller cleaning

In the following case, there is a need of cleaning the charged roller, transfer roller, and cleaning roller.

•

Warming up as switching on the power supply

•

Warming up after open-close of the cover

•

In case of termination of printing operation

•

By periodically change the bias voltage that is implied to each roller during continuous printing,

transfer the attached toner from roller to image drum and then return it to developing device.

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Oki Data CONFIDENTIAL

Separating clutch

Feeding paper

Heater

Heat roller

Thermistor

Backup roller

Pressuring spring

Thermostat

6. Fusing

Af

The thermistor that contacts the Heat roller adjusts the Heat roller temperature to the temperature

The back up roller is held by the pressure springs on each terminal due to the pressure applied.

ter the termination of transfer the unsettled toner image is settled to paper by heat and pressure
while passing between Heat roller and Back up roller. Heat roller is Teflon coated and is mounted by
heater that can generate heat (Halogen lamp).

specified by the menu complying with the paper width. For safety the thermostat shuts off the voltage
supply to the Heater by opening the thermostat in the case of abnormally temperature increasing.

2. Operational explanation

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Oki Data CONFIDENTIAL

：

：
：
：

：

：

：

：

：

Face down stacker

Face up stacker

The 2nd ejecting roller

The 1st ejecting roller

Backup roller

Duplex unit

Ejecting
sensor lever

Resist roller

MPT feeding roller

Multipurpose tray

Conveying roller

Conveying roller

Transferring roller

Pulse motor

Paper conveying route

Driving roller (Continuous rotation)
Driving roller (Control rotation)
Driving roller

Paper level indicator lever
Indicating lever

Photo sensor
Micro switch

Magnetic clutch

Solenoid

DC motor

Heat roller

Conveying roller

Pick up roller

Pick up roller

Feeding roller

Feeding roller

Tray 1

Tray 2

2nd tray unit (option)

Entrance
sensor lever

Image drum

Writing out
sensor lever

2.2 Printing process

The paper fed from Tray 1 and Tray 2 is conveyed by feeding roller, conveying roller, and resist roller.
When feeding paper is from MPT, it is conveyed by MPT, feeding roller, and resist roller. After that the
feeding paper that is conveyed by image drum and the nip part of transfer roller forms toner image
on the paper through electrophotographic process. And then, the toner on the paper is fused by the
heat and pressure as the fuser unit passing through. The paper that fused the toner image is ejected
from the face down stacker of the ejecting roller. In the case of face up ejecting, it needs to open
the backside cover and install face up stacker. (It is unavailable for duplex printing while it is face up
ejecting.)

The above is about the operations at simplex printing, yet the below explains the operations at duplex
printing. While duplex printing, the paper, which firstly passed through the fuser unit after the backside
printing, is conveyed to the inward of Duplex Unit, by the reverse operation of the second ejecting roller
that is a certain time after removing the first ejecting roller of the paper rear side. Paper, is conveyed by
conveying roller of Duplex Unit, and then merges to the same route with the feeding paper that is from

the tray. Onwards, it is the same with the simplex printing operation by the feeding paper from tray.

2. Operational explanation



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Oki Data CONFIDENTIAL

Resist roller

Resist clutch

Entrance sensor lever

Conveying roller

Paper feeding roller

Pick up roller

DC motor
(Counterclockwise rotation)

Paper feeding clutch

Paper

Writing out sensor lever

Resist clutch

Writing out sensor lever

Resist roller

Entrance sensor lever

Paper feeding clutch

MPT paper feeding roller

Paper

DV motor
(Counterclockwise rotation)

(1) Paper feeding from Tray 1

1. As DC motor rotating (Counterclockwise rotation), if set the paper feeding clutch as ON, as the
paper feeding roller and pick up roller rotating, the paper that is inside the tray is conveyed.

2. The paper is conveyed by the conveying roller. After the entrance sensor level set to be ON, it
bumps into the stopping resist roller, a certain more amount of paper is conveyed. (This corrects
the paper skew.)

3. If set the resist clutch as ON, the paper is conveyed by resist roller.

2. Operational explanation

(2) Paper feeding from Multipurpose tray (MPT)(B420dn, B430d, B430dn)

1. As

DC motor rotating (Counterclockwise rotation), if set paper feeding clutch as ON the MPT paper

feeding roller starts to rotate, the paper in the tray is conveyed.

2. After setting th
more amount of paper is conveyed. (This corrects the skew of paper.)

3. If set the r

e entrance sensor lever as ON, the paper bumps into the stopping resist roller, a certain

esist clutch as ON, the paper is conveyed by resist roller.

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Oki Data CONFIDENTIAL

Eject roller

Eject roller

Planet gear

Paper route

Solenoid

Fuser unit

Heat roller

DC motor
(Counterclockwise rotation)

(3) Fuser unit and paper ejecting

2. Operational explanation

1. The fuser u

2. Simultaneously th

nit and eject roller is

e eject roller rotates, and then the paper is ejected.

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Oki Data CONFIDENTIAL

Fuser unit

Fuser unit

Heat roller

Heat roller

DC motor
(Counterclockwise rotation)

DC motor
(Counterclockwise rotation)

Resist roller

Resist roller

Resist clutch

Resist clutch

Resist Entrance
sensor lever

Resist Entrance
sensor lever

Duplex conveying roller

Writing out
sensor lever

Writing out
sensor lever

Duplex conveying roller

The 1st ejecting roller

The 1st ejecting roller

The 2nd ejecting
roller

The 2nd ejecting
roller

Planet gear

Planet gear

Solenoid
(OFF)

Solenoid
(ON)

[ Normal rotation ]

[ Inverse rotation ]

Belt

Duplex conveying rollerDuplex conveying roller

Belt

(4) Paper reversing and paper multi-feeding

2. Operational explanation

1. TRemoving th
planet gear starts to move, the second eject roller starts inverse rotating (Counterclockwise rotation).

2. By the i

3. Paper is c

4. After setting t
more amount of paper is conveyed. (This corrects the skew of paper.).

5. If set t

he Resist clutch as ON, paper is conveyed by Resist roller.

e first eject roller at the rear part of paper and set the solenoid as ON for a while, then the

nverse rotation of the second eject roller the paper is inversely rotated and conveyed to Duplex.

onveyed by Duplex conveying roller.

he entrance sensor lever as ON, paper bumps into the stopped resist roller, still a certain

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Oki Data CONFIDENTIAL

Magnet

Agitating bar Agitating gear

Crack part

Agitating bar

Agitating bar

Agitating gear

Sensor plate

Sensor plate

Toner sensor

2.3 Toner entrance detection

• Equipment
Toner entrance detecting equipment consists the agitating gear that agitating the agitating bar at a

certain speed and magnet that is on the agitating bar.

•

Operation
Detecting the toner low by monitoring the congruous time intervals between the magnet that is set on

the sensor plate and the magnet attached on the agitating bar,

2. Operational explanation

Operation in toner full status

•

The crack part of agitating gear meshing with the

projection portion of agitating bar, the agitating bar
rotates in accordance with the rotating of gear.

•

Even after the magnet part of the agitating Bar reaches

the highest position, it still rotates at the same speed
by the pressure of the agitating gear due to the toner
resistance.

Operation in toner low status

•

When the magnet part of the agitating bar reaches the

highest position, because there is no resistance from
toner, the agitating bar drops earlier than the gear by
the gravity itself, and stops by that status.

For this reason, the time that the magnet of agitating

Bar magnetic attracts the magnet of sensor plate
becomes longer. The toner low status can be inspected

by monitoring this time.

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Oki Data CONFIDENTIAL

Toner full status

Toner low status t1 t2 t1,t2: Magnet attracting time

• Toner sensor alarm actuates if there is not any change on toner sensor.

• Toner sensor is not monitored while main (drum) motor is stopping.

2. Operational explanation

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Oki Data CONFIDENTIAL

OFF

ON

Shutting
off

Reconnecting

Earth cable

Earth terminal

Warning

This section explains the replacement procedure of part, assembly, and unit in the working place.
Disassembling procedure relating to reassembling is conducted conversely.

3.1 Preparation for parts replacement

(1) Be sure to unplug the AC cord and interface cable before starting to replace parts.
(a) Unplugging the AC cord by the following procedures.

i) Shut off the power switch of the printer. (
ii) Unplug the AC insert plug of AC cord from the AC socket.
iii) Remove the earth wire from AC socket.
iv) Unplug the AC cord and interface cable from printer.

3. Parts replacement

)

」

「

Risk of Electric Shock

3. Parts replacement

There is a risk of electric shock during replacement of the low voltage power supply.
Use insulating gloves or avoid direct contact with any conducting part of the power supply, and caution should be

exercised during replacement.
The capacitor may take one minute to complete discharge after the AC cord is unplugged. Also, there is a possibility

that the capacitor doesn’t discharge because of a breakage of the PCB, etc., so remember the possibility of electric
shock to avoid electric shock.

(b) Reconnecting the printer by the following procedures.
i) Connect the AC cord and interface cable to the printer.
ii) Connect earth wire to the AC socket.
iii) Connect the AC insert plug to the AC socket.
iv) Turn on the power switch of the printer. (

「I」

)

(2) Do not disassemble the printer in the case of normal operation.
(3) Do not disengage the part that there is not any necessary to touch. Disassembly should be the

(4) B
(5) Be sure to temporarily install the small part such as screw, collar, and so on at its original position during

(6) D

(7) D
(8) Do not put the Print Circuit Board on the printer of on the floor directly.

43984801TH Rev.1

minimum.

e sure to use the specified maintenance tools.

disassembling because it is easy to be lost.

o not use the gloves that is easy to occur electrostatic while dealing with IC such as micro-sensor,

ROM, RAM, etc. and PCB.

o not put the print circuit board on the equipment or on the floor directly.

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