Brother HL 2060 - B/W Laser Printer, 2060 Service Manual

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MECHANICS & ELECTRONICS

SERVICE MANUAL

LASER PRINTER

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No part this publication may be reproduced in any form or by any means without permission in writing from the publisher.

Trademarks:

• BR-Script, DX-2000 and LT-2000 are registered trademarks of Brother Industries, Ltd.

• Centronics is a registered trademark of Genicom Corporation.

• PostScrip is a registered trademark of Adobe Systems Incorporated.

• IBM Proprinter XL is a registered trademark of International Business Machines Corporation.

• EPSON FX-850 is a registered trademark of Seiko Epson Corporation.

• HP-GL and HP Laser Jet 5 are registered trademarks of Hewlett Packard Company.

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PREFACE

This service manual contains basic information required for after-sales service of the laser printer (hereinafter referred to as “this machine” or “the printer”). This information is vital to the service technician in maintaining the high printing quality and performance of the printer.

This manual consists of the following chapters:

CHAPTER I : GENERAL

Features, specifications, etc.

CHAPTER II : THEORY OF OPERATION

Basic operation of the mechanical system and the electrical system, and their timing.

CHAPTER III : ELECTRICAL SYSTEM

Theory of the electronics circuit

CHAPTER IV : MECHANICAL SYSTEM

Requirements for a suitable location, disassembling and reassembling procedure of mechanical system.

CHAPTER V : MAINTENANCE AND SERVICING

Parts replacement schedule, list of tools, lubricants and cleaners.

CHAPTER VI : TROUBLESHOOTING

Reference values and adjustment, troubleshooting for image defects, troubleshooting for malfunctions, etc.

APPENDICES : Engin Block Daiagram, PCB Circuitry Diagrams, etc.

Information in this manual is subject to change due to improvement or re-design of the product. All relevant information in such cases will be supplied in service information bulletins (Technical Information). A thorough understanding of this printer, based on information in this service manual and service information bulletins, is required for maintaining its quality performance and fostering the pratical ability to find the cause of troubles.

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CONTENTS

CHAPTER I GENERAL..................................................................... I-1

1. FEATURES......................................................................................................I-1

2. SPECIFICATIONS...........................................................................................I-1

3. SAFETY INFORMATION.................................................................................I-6

3.1 Laser Safety (110 - 120V Model only)...................................................................................I-6

3.2 CDRH Regulations (110 - 120V Model only) ........................................................................I-7

3.3 Additional Information ...........................................................................................................I-7

4. PARTS OF THE PRINTER..............................................................................I-8

4.1 External Views ......................................................................................................................I-8

4.2 Cross Sectional View............................................................................................................I-9

5. STORAGE AND HANDLING OF EP-ED CARTRIDGES...............................I-10

5.1 Storage of Sealed EP-ED HC Cartridges............................................................................I-10

5.2 Storage of Unsealed EP-ED HC Cartridges........................................................................I-10

CHAPTER II THEORY OF OPERATION .........................................II-1

1. BASIC OPERATIONS.....................................................................................II-1

1.1. Mechanical Configuration....................................................................................................II-1

1.2. Main Drive...........................................................................................................................II-2

1.3. Basic Sequence of Operations............................................................................................II-3

2. LASER/SCANNER SYSTEM..........................................................................II-4

3. IMAGE FORMATION SYSTEM......................................................................II-5

3.1 Outline..................................................................................................................................II-5

3.2 Printing Process...................................................................................................................II-5

3.2 1 Electrostatic latent image formation stage..................................................................II-6

3.2 2 Developing stage ........................................................................................................II-8

3.2 3 Transfer stage.............................................................................................................II-9

3.2 4 Fixing stage...............................................................................................................II-10

3.2 5 Drum cleaning stage.................................................................................................II-10

3.3 Operation ...........................................................................................................................II-11

4. PAPER PICK-UP/FEED SYSTEM................................................................II-12

4.1 Outline................................................................................................................................II-12

4.2 Cassette Feed....................................................................................................................II-13

4.3 MP Tray Feed ....................................................................................................................II-14

4.4 Paper Jam Detection..........................................................................................................II-15

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CHAPTER III ELECTRICAL SYSTEM............................................III-1

1. MAIN PCB......................................................................................................III-1

1.1. Outline................................................................................................................................III-1

1.2. Video Controller Circuit......................................................................................................III-2

1.3. Engine Controller Circuit....................................................................................................III-6

2. PAPER FEED DRIVE CIRCUIT.....................................................................III-7

3. DISPLAY CIRCUIT........................................................................................III-9

3.1 Outline.................................................................................................................................III-9

3.2 Operation ............................................................................................................................III-9

4. LOW-VOLTAGE POWER SUPPLY ASSY ..................................................III-10

4.1 Outline...............................................................................................................................III-10

4.2 Protection Functions .........................................................................................................III-10

5. HIGH-VOLTAGE POWER SUPPLY ASSY..................................................III-12

5.1 Outline...............................................................................................................................III-12

5.2 Operation of the Components of the High-Voltage Power Supply Assy...........................III-12

CHAPTER IV MECHANICAL SYSTEM ..........................................IV-1

PRINTER DISASSEMBLING PROCEDURE..................................................... IV-2

PRINTER BODY................................................................................................ IV-3

1.1 Configuration.................................................................................................................... IV-3

1.2 Control Panel Unit............................................................................................................ IV-3

1.3 Toner Cartridge Lid.......................................................................................................... IV-3

1.4 Side Cover L ....................................................................................................................IV-4

1.5 Font Cover Assy .............................................................................................................. IV-5

1.6 Upper Cover Assy, Rear Cover Assy............................................................................... IV-5

1.6.1 Upper cover assy, rear cover assy.......................................................................... IV-5

1.6.2 Changeover guide, jam remove cover.....................................................................IV-7

1.7 Side Cover R.................................................................................................................... IV-7

1.8 DC Fan Motor................................................................................................................... IV-8

1.9 Main PCB......................................................................................................................... IV-9

1.10 Laser Unit....................................................................................................................... IV-11

1.11 Cartridge Stopper Assy.................................................................................................. IV-12

1.12 Paper Feed Chassis Unit............................................................................................... IV-13

1.13 Separation Pad Assy...................................................................................................... IV-15

1.14 MP PE Sub Actuator...................................................................................................... IV-15

1.15 P Feed /Size-SW PCB Assy .......................................................................................... IV-16

1.16 Size-Switch Spring......................................................................................................... IV-16

1.17 Regist Sensor Actuator.................................................................................................. IV-16

1.18 PE Sensor Actuator MP................................................................................................. IV-17

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1.19 Tray Sensor Holder........................................................................................................ IV-17

1.20 Roller Holder.................................................................................................................. IV-18

1.21 Paper Pick-up Roller Assy, Bearing............................................................................... IV-18

1.22 Paper Pick-up Solenoid.................................................................................................. IV-20

1.23 Paper Feed Motor Assy ................................................................................................. IV-20

1.24 MP Tray Cover............................................................................................................... IV-21

1.25 MP Tray Assy................................................................................................................. IV-22

1.26 Paper Path Separation Plate, Paper Path Separation Film ...........................................IV-23

1.27 Latch ..............................................................................................................................IV-23

1.28 Fixing Unit (for both 120V and 230V, the only difference is the halogen heater)........... IV-24

1.29 Transfer Unit .................................................................................................................. IV-27

1.30 DC Gear Holder Assy ....................................................................................................IV-28

1.31 PS Switch Wire, Remote Switch.................................................................................... IV-29

1.32 High-Voltage Power Supply PCB Assy.......................................................................... IV-29

1.33 Low-Voltage Power Supply PCB Assy........................................................................... IV-30

1.34 Toner Cartridge (EP-ED HC Cartridge) .........................................................................IV-31

1.35 Paper Tray ..................................................................................................................... IV-32

CHAPTER V MAINTENANCE AND SERVICING............................V-1

1. PERIODICAL REPLACEMENT PARTS ........................................................ V-1

2. CONSUMABLE PARTS STANDARD ENDURANCE TABLE........................ V-1

3. LIST OF STANDARD TOOLS........................................................................ V-2

4. LIST OF LUBRICANTS AND CLEANERS..................................................... V-3

CHAPTER VI TROUBLESHOOTING..............................................VI-1

1. INTRODUCTION .......................................................................................... VI-1

1.1 Initial Check........................................................................................................................ VI-1

1.2 Basic Procedure................................................................................................................. VI-2

2. TEST PRINTING AND MECHANICAL CHECK............................................ VI-2

2.1 Test Printing....................................................................................................................... VI-2

3. IMAGE DEFECTS......................................................................................... VI-3

3.1 Image Defect Examples..................................................................................................... VI-3

3.2 Troubleshooting Image Defects......................................................................................... VI-4

4. TROUBLESHOOTING OF MALFUNCTIONS............................................. VI-11

5. TROUBLESHOOTING PAPER TRANSPORT PROBLEMS....................... VI-18

5.1 Paper Jams...................................................................................................................... VI-18

5.2 Incomplete Paper Feed....................................................................................................VI-21

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6. OPERATION................................................................................................ VI-23

6.1 Line Inspection Mode Procedure ..................................................................................... VI-23

6.2 DRAM Test....................................................................................................................... VI-25

7. STATUS MESSAGE LIST .......................................................................... VI-26

CHAPTER VII TROUBLESHOOTING............................................VII-1

1. HIDDEN FUNCTIONS ................................................................................. VII-1

1.1 Holding down Specified key(s) at Power on...................................................................... VII-1

1.2 Off-line and Hold down Mode + FF CONT keys ............................................................... VII-2

1.3 Off-line and Hold down CONT + SEL keys..................................................................... VII-17

APPENDIX A

1. Engine Block Diagram .................................................................................. A-1

2. Paper Feed/Size-SW PCB Circuitry Diagram (1/1)....................................... A-2

3. Main PCB Circuitry Diagram (1/7)................................................................. A-3

4. Main PCB Circuitry Diagram (2/7)................................................................. A-4

5. Main PCB Circuitry Diagram (3/7)................................................................. A-5

6. Main PCB Circuitry Diagram (4/7)................................................................. A-6

7. Main PCB Circuitry Diagram (5/7)................................................................. A-7

8. Main PCB Circuitry Diagram (6/7)................................................................. A-8

9. Main PCB Circuitry Diagram (7/7)................................................................. A-9

10. Control Panel PCB Circuitry Diagram (1/1)................................................. A-10

11. Laser LD PCB Circuitry Diagram (1/1)........................................................ A-11

12. Serial NO. Description ................................................................................ A-12

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CHAPTER I GENERAL

1. FEATURES

A. This high-speed, non-impact (low-noise) printer is based on electrophotography,

electronics and laser technology.

B. The printer is compact and easy to carry. The internally-storable, front-loading

paper cassette enables you to save an occupation space for the machine; the printer can now be installed in a smaller place.

C. The charging roller, developing cylinder, photosensitive drum and cleaner of the

printer are combined into a single assembly called an “EP-ED HC cartridge”. The cartridge can be replaced by the user when necessary without a need of service call. High printing quality is maintained by a simple cleaning procedure.

D. Laser beam safety is designed into the printer. The printer is approved by the US

Center for Devices and Radiological Health (CDRH).

E. Paper can be fed in two ways, by the multi-purpose paper feed tray and paper

cassette.

F. Maintenance is easy with print component units which are directly detachable, and

they require no adjustment after reassembly.

2. SPECIFICATIONS

(1) Type Desktop page printer (2) Printing method Electrophotography (single-component dry toner) (3) Printing speed

Cassette feed 20 ppm (600 x 600 dpi or 300 x 300 dpi, A4 size)

21 ppm (600 x 600 dpi or 300 x 300 dpi, Letter size) 10 ppm (1,200 x 1,200 dpi, A4 & Letter size)

(4) First print time 16 seconds or less

(A4 size by face-down print delivery from the paper cassette)

Prestart by software command for 10 second first print (5) Warm-up (WAIT) time Max. 1 minute at 20°C (68°F) (6) Optical system

Laser Semiconductor laser

Output power : 5mW max.

Wave length : 780 nm

Scanning system Rotating six-faced polygon mirror

(7) Resolution

Horizontal 600 dots/inch and 1,200 dots/inch Vertical 600 raster lines/inch and 1,200 raster lines/inch

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(8) Printing system

Photosensitive drum OPC Charging Charging Roller Exposure Laser scanning system Development Toner projection development system Paper feed Cassette or manual feed Image transfer Roller method Separation Natural(utilizing a small drum radius),

Static charge eliminator Fixing Heated fixing roller Toner supply Included in the replaceable EP-ED HC cartridge Life expectancy 9,000 pages/cartridge

(9) Paper

Cassette feed Plain paper for Letter, Legal, A4 (A4 or letter size paper

with the print density set at level 8 with 5% coverage,

recommended: 60 g/m

- 105 g/m2)

Multi-purpose Tray Plain paper of 95 x 148 mm - 216 x 356 mm

(recommended: 60g/m

- 200 g/m2, overhead projector (OHP) film, postcards, label stock and envelopes (specified sizes)

(10) Cassette (Tray 1)

Paper cassette A4

Letter / Legal Universal (Option) : A4, Letter, Legal, Executive, ISO

B5, A5, ISO B6, A6 and approx. 20 envelopes.

Maximum load height A4: 55 mm (500 sheets of 80 g/m

paper)

Letter / Legal: 52 mm (500 sheets of 75 g/m

paper)

Feedable paper type 60 - 105 g/m

(11) Print delivery Face-down or (face-up) (12) Print delivery tray capacity

Face-down Approx. 500 sheets (80 g/m

)

Face-up Discharge only

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(13) Effective printing area

Figure 1.1 Printable Area

Effective printable area is referred to as a area within which is guaranteed the printing of all interface signal data on a hard copy without any omission. The tables below shows the effective printable area for each paper size.

Table 1.1 Plain Paper

SIZE A (mm) B (mm) C (mm) D (mm) E (mm)

A4 210.0 297.0 203.2 288.5

3.39 ± 1.0

Letter 215.9 279.4 207.4 270.9

4.23 ± 1.0

Legal 215.9 355.6 207.4 347.1

4.23 ± 1.0

B5 (ISO) 176.0 250.0 167.5 241.5

4.23 ± 1.0

Executive 184.2 266.7 175.7 258.2

4.23 ± 1.0

A5 148.0 210.0 139.5 201.5

4.23 ± 1.0

B6(ISO) 125.0 176.0 116.5 167.5

4.23 ± 1.0

A6 105.0 148.0 96.5 139.5

4.23 ± 1.0

Table 1.2 Envelope

SIZE A (mm) B (mm) C (mm) D (mm) E (mm)

COM-10 104.8 241.3 96.3 232.8

4.23 ± 1.0

MONARCH 98.4 190.5 89.9 182.0

4.23 ± 1.0

DL 110.1 221.0 101.6 212.5

4.23 ± 1.0

C5 162.2 228.6 154.1 220.1

4.23 ± 1.0

B5 (ISO) 176.0 250.0 167.5 241.5

4.23 ± 1.0

(The sizes above are nominal sizes according to ISO.) An A4 sheet accepts 80 PICA-pitch characters (203.2mm).

Printable area

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(14) Standard interfaces Automatic interface selection

• Centronics, Bi-directional parallel

• RS-232C serial

Baud rate : 150, 300,1200, 2400, 4800, 9600

19200, 38400, 57600, 115200bps Stop bit : 1 bit Start bit : 1 bit or 2 bits Data length : 7 bits or 8 bits Parity : Odd, Even, or None Protocol : Xon/Xoff or DTR

(15) Emulation Automatic emulation selection

• HP Laser Jet 5 (PCL Level 6)

• EPSON FX-850

• IBM Proprinter XL

• BR-Script level 2 (PostScript language emulation

interpreter)

• HP-GL

(16) CPU MB86832 100MHz (SPARC architecture) (17) Resident fonts 75 scalable fonts and 12 bitmapped fonts

HP Laser Jet 5, EPSON FX-850, IBM Proprinter XL Scalable Fonts:

Bitmapped Fonts (Portrait and Landscape):

• Letter Gothic 16.66 Medium, Italic, Bold, Bold Italic

• OCR-A

• OCR-B

Intellifont Compatible Fonts:

• Albertville, Extrabold

• Antique Oakland, Oblique, Bold

• Brougham, Oblique, Bold,

Bold Oblique

• Cleveland Condensed

• Connecticut

• Guatemala Antique, Italic, Bold,

Bold Italic

• Letter Gothic, Oblique, Bold

• Maryland

• Oklahoma, Oblique, Bold,

Bold Oblique

• PC Brussels Light, Light Italic, Demi, Demi Italic

• PC Tennessee Roman, Italic, Bold, Bold Italic

• Utah, Oblique, Bold, Bold Oblique

• Utah Condensed, Oblique, Bold,

Bold Oblique

Windows 3.1 Compatible Fonts:

• Tennessee Roman, Italic, Bold, Bold Italic

• Helsinki, Oblique, Bold, Bold Oblique

• BR Symbol

• W Dingbats

BR-Script Fonts:

• Atlanta Book, Book Oblique, Demi, Demi Oblique

• Copenhagen Roman, Italic, Bold, Bold Italic

• Portugal Roman, Italic, Bold, Bold Italic

• Calgary Medium Italic

Brother Original Fonts:

• Bermuda Script

• Germany

• San Diego

• US Roman

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BR-Script Level 2 Mode Scalable Fonts:

(18) RAM 8M bytes (expandable to 72M bytes with SIMMs) (19) PCMCIA card slots Two slots

Right slot for Type I and II Left slot for Type I, II and III compatible for flash memory or HDD cards

(20) Power souse USA and Canada : AC 110 to 120 V, 50/60 HZ

Europe and Australia : AC 220 to 240 V, 50/60 HZ

(21) Power consumption Printing (peak) : 1,130 WH or less

Printing (average) : 500 WH or less Stand-by : 90 WH or less Sleep : 25 WH or less

Note:

- The peak figure of power consumption is worked out when the halogen heater lamp is turned ON.

- The peak figure of power consumption is worked out excluding inrush current value.

- Be sure that the peak figure of power consumption is reference value and should be

used inside the Brother offices only. (22) Noise Printing: 55 dB A or less

Stand-by : 40 dB A or less

(23) Dimensions (W x H x D) With A4 paper cassette:

396 x 400 x 389 mm (15.6 x15.7 x 15.3 inches) With Letter / Legal paper cassette:

396 x 452 x 389 mm (15.6 x18.8 x 15.3 inches) (24) Weight Approx. 15 kg (33 Ibs) (25) Environmental conditions

Operating Temperature 10 ~ 32.5°C environment Relative humidity 20 ~ 80%RH

(No condensation allowed)

Air pressure 71.0 ~ 101.3 kPa

(0 ~ 2,500 m above sea level) Non-operating Temperature 0 ~ 35°C environment Relative humidity 10 ~ 80%RH

(No condensation allowed)

•Atlanta Book, Book Oblique, Demi, Demi Oblique

•Brussels Light, Light Italic, Demi, Demi Italic

•Brougham, Oblique, Bold, Bold Oblique

•Helsinki, Oblique, Bold, Bold Oblique

•Helsinki Narrow, Oblique, Bold,

Bold Oblique

•Copenhagen Roman, Italic, Bold, Bold Italic

•Portugal Roman, Italic, Bold, Bold Italic

•Tennessee Roman, Italic, Bold, Bold Italic

•Calgary Medium Italic

•BR Symbol

•BR Dingbats

•Albertville, Extrabold

•Antique Oakland, Oblique, Bold

•Cleveland Condensed

•Connecticut

•Guatemala Antique, Italic, Bold, Bold Italic

•Letter Gothic, Oblique, Bold

•Maryland

•Oklahoma, Oblique, Bold, Bold Oblique

•Utah, Oblique, Bold, Bold Oblique

•Utah Condensed, Oblique, Bold,

Bold Oblique

•Bermuda Script

•Germany

•San Diego

• US Roman

PR99017

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Storage conditions

• Printer Temperature Normal (total storage time x 9/10)

0 ~ 35°C

Severe (total storage time x 1/10)

High Low 35°C ~ 60°C -20°C ~ 0°C

Temperature change (within 3 minutes)

High Low

60°C 15°C -20°C 25°C Relative humidity Normal (total storage time x 9/10)

35 ~ 85%RH Severe (total storage time x 1/10)

High Low

85 ~ 95%RH 10 ~ 35%RH Air pressure 71.0 ~ 101.3 kPa Total storage time 0.5 years

• EP-ED HC cartridge Temperature Normal (2.45 years max.)

0 ~ 35°C

Severe (0.05 years max.)

High Low 35°C ~ 40°C -20°C ~ 0°C

Temperature change (within 3 minutes)

High Low

40°C 15°C -20°C 25°C Relative humidity Normal (2.45 years max.)

35 ~ 85%RH Severe (0.05 years max.)

High Low

85 ~ 95%RH 10 ~ 35%RH Air pressure 71.0 ~ 101.3 kPa Maximum total storage time:

2.5 years including used time

3. SAFETY INFORMATION

3.1 Laser Safety (110 ~ 120V Model only)

This printer is certified as a Class 1 laser product under the US Department of Health and Human Services (DHHS) Radiation Performance Standard according to the Radiation Control for Health and Safety Act of 1968. This means that the printer does not produce hazardous laser radiation, Since radiation emitted inside the printer is completely confined within the protective housings and external covers, the laser beam cannot escape from the machine during any phase of user operation.

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3.2 CDRH Regulations (110 ~ 120V Model only)

The center for Devices and Radiological Health (CDRH) of the US Food and Drug Administration implemented regulations for laser products on August 2, 1976. These regulations apply to laser products manufactured from August 1, 1976. Compliance is mandatory for products marketed in the United States. The label shown below indicates compliance with the CDRH regulations and must be attached to laser products marketed in the United States.

Figure 1.2

Caution: Use of controls, adjustments or performance of procedures other than those

specified in this manual may result in hazardous radiation exposure.

3.3 Additional Information

When servicing or adjusting the optical system of the printer, be careful not to place screwdrivers or other reflective objects in the path of the laser beam. Be sure to take off any personal accessories such as watches and rings before working on the printer. A reflected beam, though invisible, can permanently damage the eyes. Since the beam is invisible, the following label is attached to the inside of covers where danger of exposure to laser radiation exist.

CAUTION-

INVISIBLE LASER RADIATION WHEN OPEN AND INTERLOCK DEFEATED. AVOID DIRECT EXPOSURE TO BEAM. CLASS 38 LASER PRODUCT.

ADVARSEL-

USYNLIG LASER STRÅLING NÅR KABINETLÅGET STÅR ÅBENT. UNGDÅ DIREKTE UDSÆTTELSE FOR STRÅLING. KLASSE 38 LASER.

VARNING-

OSYNLIG LASERSTRÅLNING NÄR DENNA DEL ÄR ÖPPNAD OCH SPÄRRAR ÄR URKOPPLADE. STRÅLEN ÄR FARLIG. KLASS 38 LASER APPARAT.

VAROI-

AVATTAESSA JA SUOJALUKITUS OHITETTAESSA OLET ALTTINA NÄKYMÄTTÖMÄLLE LASERSÄTEILYLLE ÄLÄ KATSO SÄTEESEEN. LUOKAN 38 LASERLAITE.

ADVARSEL-

USYNLIG LASERSTRÅLING, UNNGÅ DIREKTE KONTAKT MED LASERENHETEN NÅR TOPPDEKSELET ER ÅPENT. KLASSE 38 LASERPRODUKT.

ATTENTIGM-

RADIATIONS LASER INVISIBLES QUAND OUVERT ET VERROUILLAGE ENLEVE. EVITER EXPOSITIONS DIRECTES AU FAISCEAU. PRODUIT LASER CLASSE 38.

ATTENCIÓN-

RADIACIÓN LASER INVISIBLE CUANDO SE ABRE LA TAPA Y EL INTERRUPTOR INTERNO ESTÅ ATASCADO. EVITE LA EXPOSICIÓN DIRECTA DE LOS OJOS. PRODUCTO LASER CLASE 38.

VORSICHT-

UNSICHTBARE LASERSTRAHLUNG WENN ABDECKUNG GEÖFFNET UND SICHERHEITSVERRIEGELUNG ÜBERBRÜCKT. NICHT DEM STRAHL AUSSETZEN. SICHERHEITSKLASSE 38.

Figure 1.3

MANUFACTURED : BROTHER INDUSTRIES, LTD. 15-1, Naeshiro-cho, Mizuho-ku Nagoya 467, Japan. This product complies with FDA radiation performance standards , 21 CFR chapter 1 subchapter J.

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4. PARTS OF THE PRINTER

4.1 External Views

Upper cover

Face-up print delivery port

Control panel

Centronics interface connector

MP tray

RS-232C interface connector

Tray 1

USB port

Power switch

Duplex unit, Lower tray unit connector

PCMCIA card slots

Rating label

Fan outlet port

AC inlet

Figure 1.4

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4.2 Cross Sectional View

Control panel

Low-voltage power supply assy

EP-ED HC cartridge

High-voltage power supply assy

Photosensitive drum

Paper cassette (Tray 1)

Laser unit

Pick-up rollers

Transfer unit

MP tray

Face-down tray

Registration rollers

Print-delivery path

Fixing unit

Figure 1.5

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5. STORAGE AND HANDLING OF EP-ED HC CARTRIDGES

An EP-ED HC cartridge is influenced by the storage conditions even if it is sealed in its package, so its life depends on the way in which it is used or stored. EP-ED HC cartridges should be handled carefully.

5.1 Storage of Sealed EP-ED HC Cartridges

When storing sealed EP-ED HC cartridges in a warehouse or workshop, the storage conditions shown in (25) Environmental conditions on Page 1-5 must be met. Follow the instructions below:

1) Avoid direct sunlight.

2) Do not store cartridges on a surface that is subject to vibration.

3) Do not hit or drop the packages containing cartridges.

4) The cartridges should be stored horizontal when they are removed from the body (with their label side upside).

5) Avoid putting the cartridges near a CRT screen, a disk or a floppy disk (to keep their data from being destroyed).

5.2 Storage of Unsealed EP-ED HC Cartridges

Each EP-ED HC cartridge contains a photosensitive drum that has an organic photoconductor (OPC) which deteriorates when exposed to strong light. It also contains toner. The user, therefore, should be fully informed about the correct storage and handling of EP-ED HC cartridges.

(1)Storage requirements

1) Avoid places exposed to direct sunlight or near a window. Do not leave an EP-ED HC cartridge in a car in warm or hot weather even if it is in its storage box.

2) Avoid places with a too-high or too-cool temperature and/or humidity. Also avoid

places exposed to sudden temperature or humidity changes (such as near an air conditioner outlet).

3) Avoid dusty places or places exposed to ammonia fumes or other harmful fumes.

4) Do not store an EP-ED HC cartridge in a temperature above 40°C.

(2)EP-ED HC cartridge life

The effective life of an EP-ED HC cartridge is 2.5 years from the date of manufacture (printed on the cartridge.) The expiry year and month (date of manufacture plus 2.5 years) is shown on the EP-ED HC cartridge box. An EP-ED HC cartridge used after the expiry may produce low-quality printing, so a cartridge should be used within the stated period.

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CHAPTER II THEORY OF OPERATION

This chapter describes the printer functions, the relationship between the electrical systems and mechanical systems, and the timing of operations. Striped conduits (

) indicate mechanical linkages; solid thin arrows ( ) appearing with a signal name indicate the transmission of single control signals and outlined thick arrows (

) indicate the transmission of groups of signals.

1. BASIC OPERATIONS

1.1 Mechanical Configuration

The printer functions can be divided into four blocks: the laser system, the image formation system, the paper pick-up/feed system and the control system.

Expansion memory (SIMM)

Font card

Optional I/O (MIO)

External Device

Control panel

IMAGE FORMATION SYSTEM

Cleaning unit

Photosensitive drum

Developing

unit

Laser unit

LASER SYSTEM

Transfer

separation

unit

Delivery rollers

Fixing unit

Feeder

Tray 1

Tray 2

(Option)

MP tray

Main PCB

CONTROL SYSTEM

PAPER PICK-UP/FEED SYSTEM

(2 slots)

Figure 2.1

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1.2 Main Drive

The power necessary for driving the printer is supplied by the main motor, the paper feed motor and the laser unit motor.

The main motor is controlled by the main motor drive signal (MDRIVE) output from the main PCB, and the paper feed motor is controlled by the paper feed motor drive signal output from the main PCB, and the laser unit motor is controlled by the laser unit motor drive signal (SDRIVE) output from the main PCB.

Main motor

Main motor drive signal (MDRIVE)

Main PCB

Drum gear

Photosensitive drum

Fixing unit

Paper delivery rollers

Paper feed motor

Paper feed motor drive signal

MP tray pick-up roller solenoid drive signal (MPSOL)

MP tray pick-up roller solenoid

MP tray pick-up roller

Tray1 pick-up roller solenoid drive signal (PUCL1)

Tray1 pick-up roller solenoid

Tray1 pick-up roller

Laser unit motor drive signal (SDRIVE)

Laser unit motor

Scanning mirror

Laser unit

Figure 2.2

Note: There are cases, in the following pages,

that a main motor is referred to as a DC motor, but they are identical.

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II-3

1.3 Basic Sequence of Operations

Timing for two consecutive prints on A4 paper.

Power on Print

WAIT STBY PRINT

Ready lamp

Fixing heater

Main motor

180 C control 210 C

STBY

control

180 C control

Laser unit motor

Paper feed motor

Pick-up roller solenoid

Laser diode

Registration sensor

0.18 sec

0.12 sec

1.50 sec

1.38 sec

2.54 sec

Figure 2.3

Page 21

II-4

2. LASER SYSTEM

Laser unit driver

Collimator lens

Cylindrical lens

Laser unit motor

Scanning mirror

Focusing lenses

Beam detect mirror

Reflective mirror

Photosensitive drum

Optical sensor

To external device

Main PCB

SBD DATA VOFF

Figure 2.4

In response to the print signal transmitted from the external device, the main PCB generates the drive signals (DATA,VOFF) for the laser diode and sends the signals to the laser unit.

The laser diode in the laser unit generates a laser beam modulated by DATA. The modulated laser beam is aligned into a parallel beam by a collimator lens and a

cylindrical lens and then brought to the scanning mirror which is rotating at a constant speed.

The laser beam reflected by the scanning mirror focuses on the photosensitive drum via the focusing lenses arranged in front of the scanning mirror. The path of the beam coming through the focusing lenses is reflected by the reflective mirror.

As the scanning mirror rotates at a constant speed, the laser beam scans the photosensitive drum at a constant speed.

As the photosensitive drum rotates at a constant speed and the laser beam scans the drum, an images is formed on the drum.

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II-5

3. IMAGE FORMATION SYSTEM

3.1 Outline

The image formation system is the main part of the printer. The print information, after input from the video controller circuit into the engine controller circuit as a TVDO signal, forms a toner image on the photosensitive drum.

Then the toner image is transferred onto the paper by the transfer charging roller. The image formation system is composed of the photosensitive drum the charging unit, the developing unit and the cleaning unit.

3.2 Printing Process

The major part of the image formation system is contained in the cartridge, as shown in Figure 2.5.

Figure 2.5

The cartridge used by the printer has a seamless photosensitive drum with the structure shown in Figure 2.6. The outer layer of the drum consists of an organic photoconductor (OPC); the base is aluminum. The printing process can be divided into five major stages:

Figure 2.6

1. Electrostatic latent image formation stage

Step 1 Primary charge (-) Step 2 Scanning exposure

2. Developing stage

Step 3 Development

Photoconductive layer Base

Laser beam

Developing cylinder

Primary charging roller

Cleaning blade

Photosensitive drum

Static charge eliminator

Cartridge

Transfer charging roller

Blade

Paper

Page 23

II-6

3. Transfer stage

Step 4 Transfer (+) Step 5 Separation

4. Fixing stage

Step 6 Fixing

5. Drum cleaning stage

Step 7 Drum cleaning

Electrostatic latent image formation stage

Transfer stage

Fixing stage

Drum cleaning stage

Developing stage

Paper path Direction of drum rotation

2. Scanning exposure

1. Primary charge

7. Drum cleaning

Print delivery

6. Fixing

5. Separa tion

4. Transfer

Registration

Multi-purpose tray feed

Cassette feed

3. Develop ment

Figure 2.7

3.2.1 Electrostatic latent image formation stage

This stage has two steps, which together produce a pattern of electrical charges on the photosensitive drum. At the end of the stage, negative charges remain in the unexposed “dark” area. Charges are absent from the “light” areas, where the laser beam struck (exposed) the drum surface. Since this image of negative charges on the drum is invisible to the eye, it is called an “electrostatic latent image”.

Time (t)

-100

Exposed area

Unexposed area

Primary charge (step 1)

Scanning exposure (step 2)

Primary charge (step 1)

Transfer (step 4)

Surface potential (V)

-500

Figure 2.8

Page 24

II-7

Step 1 Primary charge

Figure 2.9

As preparation for latent image formation, a uniform negative potential is applied to the photosensitive drum surface. The printer uses the charging method that directly charges the drum for the primary charge.

The primary charging roller consists of conductive rubber. In addition to DC bias, AC bias is applied to the primary charging roller to keep the potential on the drum surface uniform. This DC bias is changed with the developing DC bias. This charging method has advantages such as lower applied voltage, less ozone generation, etc., compared with the corona charge system.

Step 2 Scanning exposure

+++

___

Figure 2.10

When the laser beam scans the drum surface, it causes the charge to be neutralized in the areas struck by the beam. Areas on the drum with no charge form the electrostatic latent image.

Laser beam

Unexposed area Exposed area

DC bias

AC bias

Photosensitive drum

Primary charging roller

Page 25

II-8

3.2.2 Developing stage

Development places particles of toner onto the areas of the drum that have been cleared of charge by the laser beam. This makes a visible image. This printer uses the toner projection development method with a single-component toner.

Step 3 Development

Blade

Stirrer

Developing cylinder

Cylinder Magnet

DC bias

AC bias

Photo-

sensitive

drum

Figure 2.11

Note: The charges on the light areas on the photosensitive drum are shown as positive

in this figure. Actually they are negative, but they are more positive than the developing cylinder and explanation is simplified by regarding them as positive.

As shown in Figure 2.11, the developing unit consists of a developing cylinder and rubber blade. The developing cylinder rotates around a fixed internal magnet. The singlecomponent toner consists of magnetite and a resin binder, and is held to the cylinder by magnetic attraction. The toner is an insulator, and acquires a negative charge by friction due to the rotation of the cylinder. The areas on the drum that were exposed to the laser beam have a higher potential (are less negative) than the negatively charged toner particles on the developing cylinder. When these areas approach the cylinder, the potential difference projects the toner particles onto them. This is called toner projection, and the latent image on the drum becomes visible.

Developing cylinder surface potential

Drum surface potential (exposed area)

DC bias Drum surface

potential (unexposed area)

Time t

-V

Voltage (V)

Figure 2.12

An AC bias is applied to the developing cylinder to help project the toner particles to the drum surface and improve the contrast of the printed image. The center voltage of the AC bias (1600 Vp-p) varies with the DC bias voltage. The IMAGE DENSITY ADJUSTMENT signal (sent from the Engine CPU to the highvoltage power supply) changes the DC bias, and thus the potential difference between the cylinder and drum. This changes the density of the print. This printer has a stirring mechanism to supply toner in the cartridge smoothly to the cylinder.

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II-9

3.2.3 Transfer stage

In the transfer stage, the toner image is transferred from the drum surface to the paper.

Step 4 Transfer

Photo-

sensitive

drum

Paper

Transfer charging roller

Figure 2.13

A positive charge applied to the back of the paper attracts the negatively charged toner particles to the paper. The printer accomplishes transfer by using the charging roller method. Advantages compared with the corona transfer method are as follows:

• Low transfer voltage that is less than half that for corona transfer.

• Less ozone generation.

• The paper is supported by the transfer charging roller and photosensitive drum, so

feed is more stable.

Reference:

If the image on the photosensitive drum is not completely transferred to the paper due to jamming, etc., the toner may adhere to the transfer charging roller. The printer removes the toner from the transfer charging roller by switching the transfer voltage between positive and negative in sequence. During wait, initial rotation, and last rotation, the printer sets the primary DC voltage to zero, and sets the charge on the drum to zero. In this case, the transfer voltage is made negative to remove the negatively-charged toner on the transfer charging roller to the drum. The transfer charging roller is thus cleaned.

Step 5 Separation

Photo-

sensitive

drum

Paper

Transfer charging roller

Static charge eliminator

Figure 2.14

The stiffness of the paper causes it to separate from the drum. (Curvature separation) To stabilize the paper feed and prevent small white circles from appearing in the printed image at low temperature and humidity, the charge on the back of the paper is reduced by the static charge eliminator after transfer.

Page 27

II-10

3.2.4 Fixing stage

The toner image transferred to the paper in the transfer stage is held only by electrostatic attraction and slight physical adhesion, so even a light touch will smear the image. In the fixing stage, the toner image is fixed by heating the paper and applying pressure. This fuses the toner particles to the paper to make a permanent image.

Step 6 Fixing

Figure 2.15

The upper roller surface is PFA-coated. The upper and lower roller surfaces are grounded via a diode to prevent the negative potential of the upper roller becoming higher than that of the lower roller, resulting in the toner being drawn to the lower roller, and adhering to the lower roller surface.

3.2.5 Drum cleaning stage

In the transfer stage, not all the toner is transferred to the paper. Some remains on the photosensitive drum. This residual toner is cleaned off in the drum cleaning stage so that the next print image will be clear.

Step 7 Drum cleaning

Photo-

sensitive

drum

Figure 2.16

Prior to the next printing, the residual toner on the drum surface is scraped away by the cleaning blade to clean the drum surface. The removed toner is collected in the cleaner container.

Cleaning blade

Sweeper stripCleaner container

Upper fixing roller

Halogen heater

Toner

Paper

Lower fixing roller

Page 28

II-11

3.3 Operation

When the engine controller circuit receives a print signal (PRINT) or a pre-feed signal (PRFD) from the video controller circuit, the engine controller circuit drives the main

motor to rotate the photosensitive drum. After the drum surface is charged negatively by the primary charge roller, the laser beam

modulated by a DATA signal scans the drum surface to from a latent image on the drum. The latent image formed on the drum surface is converted into a visible image by the

toner on the developing cylinder and then image is transferred onto the paper by the transfer roller unit. Then the residual toner is removed from the drum surface with the cleaner blade.

The cartridge also has a toner sensor. When the output from this sensor falls below a certain level, it warns that the EP-ED HC cartridge will be out of toner with an alarm.

Primary charge (AC) drive (HV1AC)

Primary charge (DC) drive (HV1DC)

Developing bias (AC) drive (DBAC)

Developing bias (DC) drive (DBDC)

Transfer charger 1 drive (HVT1) Transfer charger 2 drive (HVT2) Transfer charger 3 drive (HVT3) Transfer charger 4 drive (HVT4)

Toner sensor signal 1 (TONER 1) Toner sensor signal 2 (TONER 2)

Main PCB

Laser unit

EP-ED HC cartridge

Transfer roller

High-voltage power supply PCB

Laser beam

Reflection mirror

Scanner motor drive signal (SDRIVE)

Laser diode drive signal (DATA)

Figure 2.17

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II-12

4. PAPER PICK-UP/FEED SYSTEM

4.1 Outline

If a tray1 paper pick-up roller solenoid drive signal (PUCL1) is input to the circuit while the paper feed motor is rotating, the paper pick-up solenoid comes on and the paper pick-up roller solenoid is engaged. As a result, the paper pick-up roller rotates to feed paper down to the photosensitive drum.

The paper position is controlled by the registration sensor so that the leading edge of the paper is aligned with the leading edge of the image on the photosensitive drum. After this operation, the paper is deliveried to the face down tray via the fixing unit. Paper ejection is detected by the paper ejection sensor; if printed paper has not reached or not cleared the paper ejection sensor in a specified time, the printer judges that a paper jam has occurred. In this case a paper jam is noticed to the external devise by a status signal.

Main PCB

Paper ejection sensor

Fixing rollers

Transfer roller

Main motor

Photosensitive

drum

Registration

sensor

Tray1 Pick-up

roller solenoid

Paper-

feed

motor

MP tray Pick-up

roller solenoid

MP tray

paper empty sensor

Tray paper

empty sensor

MP tray paper empty sensor signal (PEMP)

MP tray pick-up roller solenoid drive signal (MPSOL)

Paper feed motor drive signal

Tray1 pick-up roller solenoid drive signal (PUCL1)

Tray1 paper empty sensor signal (PETRAY1)

Registration sensor signal (REGIST)

Main motor drive signal (MDRIVE)

Paper ejection sensor signal (EJECT)

Stuck-full sensor

Figure 2.18

Page 30

II-13

4.2 Cassette Feed

When the fixing rollers reach the specified temperature while a cassette with paper is in the printer, the READY lamp changes from flashing to lighting.

When the engine controller circuit receives PRNT or PRFD signal from the video controller circuit, the paper feed motor starts rotation. About 0.2 seconds later, the printer actuates the tray1 pick-up roller solenoid and the pick-up roller makes one rotation. This feeds paper to the photosensitive drum.

Timing chart for the pick-up one sheet

0.12 sec

1.74 sec

1.38 sec 2.54 sec

Main motor

Paper feed motor

Registration sensor

Paper empty sensor

Pick-up roller solenoid

Paper ejection sensor

STBY PRINT STBY

PRNT or PRFD

0.12 sec

Figure 2.19

Page 31

II-14

4.3 MP Tray Feed

The timing of the MP tray feed is identical to the timing of the cassette paper feed except for the following points:

(1) The paper empty sensors are different.

Cassette feed : Tray1 paper empty sensor MP tray feed : MP tray paper empty sensor

(2) The pick-up roller solenoids are different.

Cassette feed : Tray1 pick-up roller solenoid MP tray feed : MP tray pick-up roller solenoid

0.12 sec 0.12 sec

Main motor

Paper feed motor

Registration sensor

Paper empty sensor

Pick-up roller solenoid

Paper ejection sensor

STBY PRINT STBY

PRNT or PRFD

0.65 sec

Figure 2.20

Page 32

II-15

4.4 Paper Jam Detection

The printer has a registration sensor and a paper eject sensor at the paper outlet to detect whether the printed paper has been fed correctly. A paper jam is detected by whether the paper is present at the sensor at the check periods programmed in the engine CPU memory. If the engine CPU detects a paper jam, the main motor, paper feed motor and scanner motor is turned off immediately and the jam status is transmitted to the video controller circuit.

A paper jam is detected in any of following conditions:

1) Paper exists at the paper ejection sensor or the registration sensor when power is

switched on. (JAM REAR or JAM INSIDE)

2) Paper has not reached the registration sensor within a specified time (JAM

TRAYS).

3) Printed paper has not passed through the registration sensor within a specified

time (JAM INSIDE (1) ).

4) Printed paper has not reached the paper ejection sensor within a specified time

(JAM INSIDE (2) ).

5) Printed paper has not passed through the paper ejection sensor within a specified

time (JAM REAR).

Jam tray

Main motor

Registration sensor

Pick-up solenoid

STBY PRINT

Jam check

JamNormal

3.00 sec3.00 sec

Figure 2.21

Jam inside (1)

Jam

2.94 sec2.94 sec

Normal

Main motor

Registration sensor

Paper feed motor

Jam check

STBY PRINT

Figure 2.22

Page 33

II-16

Jam inside (2)

STBY PRINT

JamNormal

1.50 sec1.50 sec

Main motor

Paper ejection sensor

Paper feed motor

Jam check

Figure 2.23

Jam rear

STBY PRINT

JamNormal

5.74 sec

Main motor

Paper ejection sensor

Paper feed motor

Jam check

Figure 2.24

If the stuck-full sensor detects a status that the paper is inside the printer for 20 seconds, it sends out the full signal.

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III-1

CHAPTER III ELECTRICAL SYSTEM

Electric signal levels are expressed by “High” (approximate the supply voltage) or “Low” (approximate 0V). Signals with hyphen or slash, such as -FSRD or FSRD/, are low-active and signals without hyphen or slash, such as FSRD, are high-active signals.

1. MAIN PCB

1.1 Outline

The Main PCB consists of the Video Controller Circuit and the Engine Controller Circuit. The Video Controller Circuit performs the following functions. (1) Converts data received from an external device, such as a personal computer,

through Centronics parallel interface or RS-232C serial interface into video data and transfers it to the Engine controller circuit.

(2) Displays the current printer status in LED and LCD, and enables settings from the

control panel.

The operation sequence of the printer controlled by a microprocessor in the Engine Controller Circuit. The Engine Controller Circuit outputs signals to drive the various loads on the laser diode, laser unit motor, main motor, etc. according to the print commands and image data from the external device.

IC CARD (PCMCIA)

MIO BOARD

Regurator

+24V

CDCC (bolse) IF

RS-232C IF

ASIC MB87F1611

Video controller

Engine controller

Engine CPU

M38063

+24V

+5V

GND

CONTROL PANEL

Low-voltage Power Supply

Gate Array µPD65632GF(IO PORT. ENGINE)

MASK ROM

32M mask 2 4MB

DRAM

16M 4 8MB

DRAM (SIMM 2 slots)

64MBmax.

EEPROM

24CO4 4Kbit

Main CPU

MB86832

Main PCB

MIO RELAY

(CONNECTOR)

PCB

USB IF

IC CARD (PCMCIA)

Figure 3.1 Main PCB Block Diagram

Page 35

III-2

1.2 Video Controller Circuit

(1) CPU block

CPU(#33) MB86832-100 manufactured by Fujitsu RISC chip Clock speed: 33.1768 Mhz (3 times faster than the base clock) Appearance: 178-pin QFP Voltage: 3V

(2) ASIC/Gate Array Block

• #19 MB87F1611(Fujitsu) - 240-pin QFP Controls the address decoder, timers and interfaces (Centronics and RS-232C).

• Controls HRC(High Resolution Control), GSC(Gray Scale Control) and economy mode, drivened by 3V.

• #2 µPD65632GC - 100-pin QFP Controls the I/O ports and others.

(3) Font Card Block

• Font Card (option) The font card has a 64MB memory area and is controlled by the 16-bit bus. The card is supplied with 12V power in the slot 2 because the PCMCIA card requires 12V power supply when writing or erasing data. The address bus is buffered by LS245 and the data bus, is buffered by LCX245.

(4) Centronics/RS-232C interface block

• Centronics parallel interface Data transmission and reception are controlled by the MB87F1611 (#19).

• RS-232C Data transmission and reception are controlled by the MB87F1611 (#19). The ADM202JRN (#35) serves as driver/receiver.

(5) SIMM block

• SIMM (Single-Inline-Memory-Module) allows memory extension up to 72MB

• 2 SIMM sockets are available.

• SIMM should be of 72-pin type and its access time should be less than 70 ns.

• 12 types of SIMM (1MB, 2MB, 4MB, 8MB, 16MB and 32MB) can be combined:

1MB MH25632BJ-7 (MITSUBISHI), HB56D25632B-7A (HITACHI) 2MB MH51232BJ-7 (MITSUBISHI), HB56D51232B-7A (HITACHI) 4MB MH1M32EJ-7 (MITSUBISHI), HB56A132BT-7A (HITACHI) 8MB MH2M32EJ-7 (MITSUBISHI), HB56A232BT-7A (HITACHI) 16MB THM324000BSG-60, -70, -80 (TOSHIBA) 32MB THM328020BSG-60, -70, -80 (TOSHIBA)

Note: Fast page type and EDO type can be used together although it is not

recommended.

1) The SIMMs have its printed marking on the PCB by silk screen: SLOT1 and

SLOT2, respectively.

2) The attached Printer SIMM map shows the memory map for 4 SIMMs combined.

Page 36

III-3

(6) ROM block

ROMs store the CPU control program and font data. ROMs are two 32Mbit masked ROMs. Optional sockets are available for two 8Mbit EPROM (µPD27C8000DZ-120 - NEC or equivalent) for expansion. ROM access time should be less than 120nsec.

(7) DRAM block

DRAMs are used for receiving buffer or working area of the CPU. The DRAM block contains four 16Mbit DRAMs, thus having 8MB memory capacity in total. The refreshing method is CBR (Cas Before Ras). DRAM access time should be less than 80nsec.

Page 37

III-4

0000_0000 0040_0000 0080_0000

0100_0000

0200_0000

0400_0000

0600_0000

0800_0000

0B00_0000

0C00_0000

0E00_0000

0FC0_0000 0FD0_0000

(256MB)

ROM

(4 bunk)

Font card 1

(64MB)

Font card 2

(16MB)

ROM3

(128MB)

Ghost for CS1#

CPU

DRAM

(MAX 128MB)

64MB x 8 bunk

Reverved

(16MB x 4)

MIO / EOT

ASIC

Ghost for CS4#

There are 4 CS terminals for CSROM#0 - CSROM#3. 2MB or 4MB is selectable from CSROM#0 - CSROM#2. If the both are selected, it will become one memory space and ROM#0 supports upto 16MB. CSROM#3 is a rest of the memory space with 256MB

$5E00_0000

$5E20_0000

$5E40_0000

$5E60_0000

$5E80_0000

$5EA0_0000

$5EC0_0000

$5EE0_0000

$5F00_0000

$5F20_0000

$5F40_0000

$5F60_0000

$5F80_0000 $5FA0_0000

$5FC0_0000

$5FFF_FFFF

USB

HRC/GS setting

Memory wait setting

LSB setting

Write to LSB

DRAM transfer

SDRAM mode setting

Soft support function

FC control setting

Memory structure

setting

Timer Engine

CDCC

Easy serial 1

16550

Switching clock

Default setting

$5FE0_0000

Mediation level setting

Interruption

External interruption

Figure 3.2 Memory map

Page 38

III-5

Option I/F Connector

SIMM Block

MASK ROM (Flat package)

USB I/F

RS232C I/F

ASIC MB87F1611

CPU (VIDEO)

Centronics I/F

Option ROM Socket

DRAM Block

Control Panel Connector

ASIC MPD65632GC

CPU (ENGINE)

PCMCIA Card Connector

Figure 3.4 Main PCB

Page 39

III-6

1.3 Engine Controller Circuit

Engine

Controller

Circuit

Primary charging roller

MP Tray Pick-up Solenoid

Laser Unit

High-Voltage

Power Supply

Assy

Paper Feeder

PCB

Detectors

Main Motor

Low-Voltage

Power Supply

Assy

Pick-up Motor

Fixing Unit

Transfer roller

Developing cylinder

Toner sensor

Pick-up Solenoid

Figure 3.5 Engine Controller Block Diagram

Components in the Circuit (refer to the next page)

A. Engine Control CPU B. Low-Voltage Power Supply Connector C. Fuser Unit Control

C-1. Heater Drive Circuit C-2. Heater Temperature Input Signal

C-3. Paper Eject Input Signal D. Paper Feeder PCB Control Signals and Connector E. Option Interface Circuit and Connector F. High-Voltage Power Supply Control Circuit and Connector G. Laser Unit Control

G-1. Laser Unit Motor Control Circuit

G-2. Laser Diode Drive PCB Control Circuit H. Fan Motor Drive Circuit I. Main Motor Control Circuit J. Cover Open Detect Circuit K. Safety Door Switch Circuit

Page 40

III-7

2. PAPER FEED DRIVE CIRCUIT

A. Connector to Main PCB B. Pick-up Motor Drive Circuit and Connector C. Pick-up Solenoid Drive Circuit and Connector D. Multi Purpose Tray Pick-up Solenoid Drive Circuit and Connector E. Sensors

E-1. Tray1 Paper Empty Sensor

E-2. Multi Purpose Tray Paper Empty Sensor

E-3. Regist Sensor

E-4. Pre-Regist Sensor

E-5. Paper Detect Sensor in Duplex Unit F. Tray1 Paper Size Detect Switches

Refer to the next page.

Page 41

III-8

E-1

E-2

E-3

E-4

E-5

Figure 3.7 Paper Feed/Size-SW PCB Circuit

Page 42

III-9

3. DISPLAY CIRCUIT

3.1 Outline

The control panel of this printer has four LED lamps, one LCD display, and eight switches. The control panel is connected to the Main PCB and its functions are as follows: (1) The LCD shows the printer status and error message in alpha-numeric characters. (2) The LED lamps indicate the operating conditions of the printer. (3) The printing mode and LCD brightness can be changed by switches.

Main PCB

LCD

PAD4-PAD7 LCDE, LCDRS

LED4 (ONLINE)

LED5 (ONLINE)

LED2 (DATA)

SW1 (FORMFEED) SW4 (SEL) SW2 (UP) SW5 (FONT)

SW3 (DOWN) SW6 (SET) LED1 (READY)

LED3 (ALARM) SW8 (CONTINUE) SW7 (MODE)

Figure 3.8 Display Circuit

3.2 Operation

Indicators on the control panel (LED lamps and LCD) are controlled by the video controller circuit. All the switch signals are input to the video controller circuit. Signals Descriptions: LED1 - LED4 On-off control for the respective LED lamps.

Illuminating when Low and extinguished when High. PAD4 - PAD7 LCD control signal. LCDRS A signal to distinguish PAD4 - PAD7 into command and data. LCDE A signal to start the operation. SW1 - SW8 Input signals from the switches.

Going Low when each switch is pressed.

Page 43

III-10

4. LOW-VOLTAGE POWER SUPPLY ASSY

4.1 Outline

The low-voltage power supply assy consists of the low-voltage generating block (hereinafter the DC block) and the heater drive circuit block to turn the heater on (hereinafter the AC block). When the power switch (SW1) is turned on, AC power is supplied to the low-voltage power supply assy. The DC block generates +5 VDC, and +24 VDC. When the heater is turned on, AC power is supplied to the AC block under control of the heater on-off signal from the engine controller. +24V output is reserved in the DC block, for the cooling fan for the low-voltage power supply assy.

4.2 Protection Functions

Each of the power supply circuits, +5V, and +24V, has a protection function to prevent the circuit from accident by automatically cutting off the power supply in the case of a over-voltage or over-current of the load. When the cooling fan stops to rotating, an over-voltage protection or a short-circuit protection function is activated, and all the DC power supplies are cutoff. In this case check and clear the cause on the load after turning the power switch (SW1) off, and then switch the power on again at least one minute after the power shut-down.

Page 44

III-11

Heater

Control

Thermal

Fuse

Lamp

H1TH1

AC IN

Power

Switch

(SW1)

Noise

Filter

Rectfier

Inlet

Transformer

Rectfier

Chopper

Over

Voltage

Detector

Feedback Control

HEAT/

+24V

+5V

±0V

+24VRET

FANLOCK/

P101

To Heater Circuit

Figure 3.9 Low-Voltage Power Supply PCB Block Diagram

Page 45

III-12

5. HIGH-VOLTAGE POWER SUPPLY ASSY

5.1 Outline

The High-Voltage Power Supply Assy supplies the high-voltage for the charging roller, the developer cylinder and the transfer roller according to the engine CPU’s control signals. The block diagrams are shown Fig 3.10 and 3.11.

5.2 Operation of the Components of the High-Voltage Power Supply Assy

(1) Primary charging

When input signal/HV1AC gets the Low level, the primary high-voltage AC is applied to the primary charging roller. And when input signal/HV1DC gets the Low level, the primary high-voltage DC is applied to the primary charging roller. The primary high-voltage DC changes with developer bias DC according to values of the input signal DNSTY which is for print density adjustment.

(2) Developer bias

When input signal/DBAC gets the Low level, the developer bias AC is applied to the developer cylinder. And when input signal/DBDC gets the Low level, the developer bias DC is applied to the developer cylinder. The developer bias DC changes according to values of the input signal DNSTY which is for print density adjustment, like the primary high-voltage DC.

(3) Transfer charging

Transfer bias is controlled by the input signals HVT1 - 4 and HVTFB. When the input signal/HVT1 gets the Low level and the input signal HVT4 gets 3.7V, negative high-voltage is applied to the transfer roller. When the input signal/HVT2 gets the Low level, positive high-voltage is applied to the transfer roller. When the input signal/HVT3 gets the Low level, positive high-voltage about 1100 times that of the input signal HVT4 is applied to the transfer roller. The input signal HVTFB has voltage about 1/1100 times the positive voltage generated on the transfer roller. Once the engine CPU is informed of this voltage, the bias applied to the transfer roller can be known. Note: The HVT2 signal generates high-voltage irrespective of the HVT4 signal.

(4) Toner sensing

Voltage levels of the input signals TONER1 and TONER2 allow the engine CPU to check if the cartridge is set or not and if toner is empty. The TONER1 carries the voltage generated at the toner sensor and the TONER2 carries the developing bias output value.

Page 46

III-13

Current Buffer

Sin Wave Generator

High-Voltage Electrode

Control Unit (Feedback Circuit)

(ON / OFF Circuit)

Pulse Generator

Control Unit

(DNSTY Control Circuit) (ON / OFF Circuit)

(Feedback Circuit)

Pulse Generator

Control Unit (Feedback Circuit)

(ON / OFF Circuit)

Control Unit

(DNSTY Control Circuit) (ON / OFF Circuit)

(Feedback Circuit)

PULSE

DEVELOPER BIAS DC

DEVELOPER BIAS AC

PULSE

PRIMARY HIGH-VOLTAGE DC

PRIMARY HIGH-VOLTAGE AC

1 5 2 3 4

/HV1AC

DNSTY

/HV1DC

/DBAC /DBDC

High-Voltage Electrode

DBOUT

/HVHALF

Figure 3.10 High-Voltage Power Supply Block Diagram 1

Page 47

III-14

TRANSFER HIGH-VOLTAGE

TONER SENSE

DBOUT

8 7

6 11 13 12 14 15

/HVT3 /HVT2

HVTFB

HVT4

/HVT1 TONER1 TONER2

24VRET

+24V

Pulse Generator

Current Buffer

High-Voltage Electrode

Current Buffer

Attenuator

Constant Current Control Unit

(Feedback Circuit) (ON / OFF Circuit)

Toner Sense Control Unit

(HVT4 Control Circuit)

Current Buffer

(Toner 1 Circuit) (Toner 2 Circuit)

Toner Sense Electrode

Pulse Generator

Constant Voltage Control Unit

Figure 3.11 High-Voltage Power Supply Block Diagram 2

Page 48

IV-1

CHAPTER IV MECHANICAL SYSTEM

■■ Safety Precautions

To prevent the creation of secondary problems by mishandling, observe the following precautions during maintenance work. (1) Always turn off the power before replacing parts or units. When having access to

the power supply, be sure to unplug the power cord form the power outlet.

(2) Be careful not to lose screws, washers, or other parts removed for parts

replacement. (3) Be sure to apply grease to the teeth of gears. (4) When using soldering irons and other heat-generating tools, take care not to

damage the resin parts such as wires, PCBs, and covers. (5) Before handling the PCBs, touch a metal portion of the equipment to discharge

static electricity, or the electronic parts may be damaged due to the electricity

charged in your body. (6) When transporting PCBs, be sure to wrap them in conductive sheets such as

aluminum foil. (7) Be sure to reinsert self-tapping screws correctly, if removed. (8) Unless otherwise specified, tighten screws to the torque values listed below.

• Tapping screws S tight M3 : 7kgf • cm B tight M3 x 6 : 5kgf • cm

M3 x 8 : 7kgf • cm

• Stepped screws

M3 : 7kgf • cm M4 : 10kgf • cm

(9) When connecting or disconnecting cable connectors, hold the connector bodies

not the cables. If the connector has a lock, always slide the connector lock to unlock it.

(10) After repairs, check not only the repaired portion but also that the connectors and

other related portions function properly before operation checks.

■

■ Notes

• On the next page is a disassembly order flow which helps you access the object component.

• Unless otherwise specified, the disassembled parts or components should be reassembled in the reverse order of removal.

Page 49

IV-2

■

■ PRINTER DISASSEMBLING PROCEDURE

Printer body

Toner cartridge lid

Side cover L

Control panel unit

Upper cover

Cartridge stopper ASSY

Laser unit

Fixing unit

Main PCB

DC fan motor

Front cover

Upper cover ASSY

Rear cover ASSY

Side cover L

Font cover ASSY

Side cover R

Paper feed chassis unit

Side cover R

Regist sensor actuator

P feed/size-SW PCB ASSY

Size -switch spring

Paper path

separation plate

PS switch wire

Remote switch

Latch

Transfer unit

DC gear holder ASSY

High-voltage

power supply

unit

Low-voltage

power supply

unit

PE sensor actuator

Tray sensor holder

Roller holder Paper pick-up roller

Paper feed motor ASSY

Font cover ASSY

*Toner cartridge

Paper tray

Separation pad ASSY

MP PE sub actuator

MP tray cover

MP tray ASSY

Page 50

IV-3

PRINTER BODY

1.1 Configuration

Figure 4.1

1.2 Control Panel Unit

(1) Release the Stopper. (2) Remove the Lead wire cover. (3) Remove the 3 screws from the bottom of the Control panel unit, and remove the 3

screws from the Interlock actuator.

(4) Pull out the Harness connector.

Note: Carefully remove the Panel cover from the rib.

Figure 4.2

Toner cartridge lid

Upper cover ASSY

Control panel unit

Side cover L

Paper tray

Rear cover ASSY

Side cover R

Font cover ASSY

Screw

Control panel unit (Bottom)

Lead wire cover

Interlock actuator

Page 51

IV-4

1.3 Toner Cartridge Lid

(1) Remove the supporter from the Toner cartridge lid. (2) Push the right side of the Toner cartridge lid to release the boss. (3) Hold the right side of the Toner cartridge lid and Move it towords the left side. (4) Push the left side of the Toner cartridge lid to release the boss. (5) Remove the Toner cartridge lid from the Upper cover.

Figure 4.3

1.4 Side Cover L

(1) Release the lock by pinching the lever on the left top surface ( ) and remove the

cover by pulling it rearward ( ).

Figure 4.4

Cleaner brush

Hook lever

Side cover L

Toner cartridge lid

Upper cover ASSY

Supporter

Open the Toner cartridge lid

Page 52

IV-5

1.5 Font Cover ASSY

(1) Remove the font cover ASSY by loosening the screw on the top and releasing the

hooks on the bottom.

Figure 4.5

1.6 Upper Cover ASSY, Rear Cover ASSY

1.6.1 Upper cover ASSY, Rear cover ASSY

(1) Loosen the top left screw and 2 screws at the top of the Rear cover ASSY. (2) Release the hook at the right side of the Upper cover ASSY and lift it upwards to

remove.

Note: Pay attention to the Paper sensor actuator when removeing the Upper cover

ASSY. The hook is released automatically by removing the Upper cover ASSY in the direction of the arrow.

Figure 4.6

Screw

Hook

Font cover ASSY

Hook

Upper cover ASSY

Hook

Screw

Swing tray

Page 53

IV-6

(3) Loosen the 2 screws on the

bottom of the Rear cover ASSY.

Figure 4.7

(4) Disconnect the Paper eject sensor harness from the Paper eject sensor PCB ASSY.

Figure 4.8

(5) Remove the Rear cover ASSY.

Upper cover ASSY

Rear cover ASSY

Screw

Paper ejetct sensor PCB

Paper ejetct sensor harness

Rear cover ASSY

Page 54

IV-7

1.6.2 Changeover guide, Jam remove cover

(1) Open the jam remove cover by hooking your finger on 2 dents ( ). (2) Remove the jam remove cover with its center part opened by bending the arm of

the boss both on sides ( ) toward the front ( ).

(3) Remove the changeover guide from the boss by bending the right hook (viewed

from the rear) of the Rear cover ASSY ( ), then remove the changeover guide ( ).

Figure 4.9

1.7 Side Cover R

(1) Remove the screw and remove the Front cover.

Figure 4.10

Jam remove cover

Hole

Boss

Rear cover ASSY

Changeover guide

Dents

Screw

Front cover

Hook

Page 55

IV-8

(2) Remove the Side cover R by releasing the 4 hooks.

Note: Before releasing the 4 hooks, remove the paper tray.

Figure 4.11

1.8 DC Fan Motor

(1) Remove the DC fan motor from the DC fan motor holder by loosening the 2

screws.

(2) Loosen the screws securing the Holder spacer and remove the entire DC fan

motor holder.

Figure 4.12

<Rear>

<Front>

Side cover R

Hook at 4 places

DC fan holder

2 screws

Screws (yellow)

DC fan motor

Holder spacer

Page 56

IV-9

1.9 Main PCB

(1) Loosen the 2 screws and remove the SIMM replace lid.

Figure 4.13

(2) Remove the 7 screws and the MIO box.

Figure 4.14

MIO box

Screws

Screw

SIMM replace lid

Page 57

IV-10

(3) Remove the PCB holder by loosening 10 screws from the PCB holder, 2 screws

from the Centronics connector and 2 screws RS-232C connector.

Figure 4.15

(4) Remove the SW panel harness 22P and the Paper feed flat cable 21P. (5) Remove the DC fan motor harness 3P, the Fuser harness 4P, the Polygon harness

5P, the LSR flat cable 6P, the DC motor harness 5P, the HV harness 16P and the LV harness 8P.

Figure 4.16

PCB holder

Screws

Main PCB

PCB holder

< View from the top >

Centronics connector lock wire

Paper feed flat cable 21P

Polygon harness 5P

HV harness 16P

DC motor harness 5P

LV harness 8P

SW panel harness 22P

Fuser harness 4P

LSR flat cable 6P

LSR fan motor harness 2P

LV fan motor harness 2P

Paper eject sensor harness 3P

DC fan motor harness 3P

PR99135

Page 58

IV-11

(6) Remove 8 screws and the Main PCB ASSY.

Figure 4.17

1.10 Laser Unit

(1) Unplug the LSR flat cable connector (6P), and LSR harness connector (14P). (2) Remove the beam from the chassis by loosening the screws. (3) Remove the Laser unit from the chassis by loosening the screws.

Caution: Do not disassemble the Laser unit, it can be only adjusted at the factory only.

8 screws

Main PCB ASSY

LSR flat cable 6P connector

LSR harness 14P

Laser unit

Screws

Beam

Polygon control PCB

Release the hook to loosen the cable tie.

Figure 4.18

Figure 4.19

Page 59

IV-12

1.11 Cartridge Stopper ASSY

(1) Remove LSR harness 5P, the Paper eject sensor harness and DC fan motor

harness from the cable clump. (2) Remove the Duct by releasing the 2 hooks. (3) Remove 3 M holders by loosening the screws.

Figure 4.20

(4) Remove the screw for the Laser fan motor and remove it. (5) Remove the Laser flat cable form the ferrite core. (6) Loosen 4 screws and remove the Laser unit mount plate in the direction of the

arrow (the Ground leaf spring is also released at the same time.)

Figure 4.21

M holder

Ground leaf spring

Screws

< Front >

< Rear >

< Left side >

< Right side >

Laser unit mount plate

Cartridge stopper ASSY

LSR harness 5P

Duct

M holder

Page 60

IV-13

(5) Release the hook by bending the arm of the Cartridge stopper ASSY (

), slide the

Cartridge stopper ASSY to the left (

) and the remove the Cartridge stopper ASSY

(

Figure 4.22

1.12 Paper Feed Chassis Unit

(1) Pull out the unit by loosening the 8 screws (4 screws for front and 4 screws for

bottom).

Figure 4.23

Note: When installing the Paper feed chassis unit, screw the left chassis of this Paper

feed chassis unit, set the paper tray, displace the right chassis of this unit up to the paper tray and screw them.

Screws

Paper feed chassis unit

Laser unit mount plate

Cartridge stopper ASSY

Page 61

IV-14

(2) Remove the Paper hold front and the Paper hold rear by pushing the top of the

Paper hold front and sliding it down.

Figure 4.24

(3) Release the left cartridge hold roller and remove the cartridge guide L (by

loosening the screw and releasing the hook) then pull out feed flat cable 20P.

Figure 4.25

(4) Remove the Paper feed chassis unit.

Figure 4.26

Paper feed chassis unit

Screw

Hook (the rear side)

Cartridge hold roller

Cartridge guide L

Feed flat cable 20P

Paper hold front

Screws

Paper hold rear

Page 62

IV-15

1.13 Separation pad ASSY

(1) Release the hook and remove the Paper pick-up roller ASSY. (2) Remove the Separation pad ASSY by pulling it out from the Paper feed guide

upper.

Figure 4.27

(3) Remove the spring from the Separation pad ASSY.

Figure 4.28

1.14 MP PE Sub Actuator

(1) Pull out the actuator upward from the MP tray ASSY (pay attention to the hook

because it is fragile).

Figure 4.29

Separation pad ASSY

Separation pad spring

Paper feed guide upper

Paper pick-up roller ASSY

Paper pick-up roller collars

Separation pad ASSY

Hook

MP PE sub actuator

Page 63

IV-16

1.15 P Feed /Size-SW PCB ASSY

(1) Release 2 solenoid harness connectors. (2) Put the 3 chassis L tabs to their original position. (3) Remove 2 screws securing the Size-SW PCB ASY and remove P Feed/Size-SW

PCB ASSY.

Figure 4.30

1.16 Size-Switch Spring

(1) Pull out the Size-switch spring.

1.17 Regist sensor actuator

(1) Remove the actuator by shifting it to the left from the chassis hole.

Regist sensor actuator

Size-SW PCB

Size-switch spring

Tabs

2 solenoid harness connector

2 screws

P feed/ size -SW PCB ASSY

Paper feed motor harness connector

Figure 4.32

Figure 4.31

Size-switch spring

Size-SW PCB

Screws

Paper Feed Frame L

7.7-8.5 mm

PR99176

Page 64

IV-17

1.18 PE Sensor Actuator MP

(1) Pull out the actuator by shifting it to the right from the chassis hole.

Figure 4.33

1.19 Tray Sensor Holder

(1) Disengage the DU (Duplex) detection actuator from the hook and slide it to the

outside. (2) Loosen the screw and remove the holder by lifting it from the chassis.

PE sensor actuator tray, PE actuator link, DU detection actuator

1) Remove the PE actuator link from the PE sensor actuator tray.

2) Remove the PE actuator link from the Tray sensor holder.

3) Remove the PE sensor actuator tray from the Tray sensor holder.

4) Remove the DU detection actuator from the Tray sensor holder.

Figure 4.34

PE sensor actuator MP

DU detection actuator

Hook

Screw

PE sensor actuator tray

Tray sensor holder

PE actuator link

Page 65

IV-18

1.20 Roller Holder

(1) Remove the Gear 28. (2) Loosen and pull out the 2 screws.

Figure 4.35

1.21 Paper pick-up roller ASSY, Bearing

(1) Pull out the MP paper pick-up gear 35 and the Tray paper pick-up gear 35, from

the Paper pick-up roller shafts.

Figure 4.36

Bearings

MP paper pick-up gear 35

Paper pick-up roller shafts

Tray paper pick-up gear 35

Gear 28

Roller holder

Screws

Page 66

IV-19

(2) Loosen the bearing screws and pull out the paper pick-up rollers.

*When only the Paper feed rollers are to be replaced, they can be replaced without

removing the Paper feed unit (with the body assembled).

Figure 4.37

(3) Pull out the Paper pick-up roller shafts. (4) Remove the Paper pick-up roller collars from the Paper pick-up rollers ASSY.

Figure 4.38

Bearing

Paper pick-up roller ASSY

Bearing

Paper pick-up roller shafts

Paper pick-up roller collars

Paper pick-up roller ASSY

Collars stopper

Paper pick-up roller ASSY

Paper pick-up roller collars

Page 67

IV-20

1.22 Paper Pick-up Solenoid

(1) Remove each solenoid by loosening their screw.

Figure 4.39

1.23 Paper Feed Motor ASSY

(1) Pull out the Paper feed motor ASSY by loosening its 2 screws.

Figure 4.40

Screw

Paper pick-up solenoid

Screw

Paper pick-up solenoid

Paper feed motor ASSY

Screw

Page 68

IV-21

(2) For each ASSY, loosen a screw and pull out the bearing and the 6 washers.

See the picture below

Figure 4.41

1.24 MP Tray Cover

(1) Remove the MP tray cover from the Paper feed chassis unit by bending its hook on

both sides.

Figure 4.42

Hook

MP tray cover

Paper feed chassis unit

MP extension tray

Paper feed roller ASSY 70s

Washer

Screw

Washer

Screws

Paper feed roller ASSY 60

Bearings

Bearing

Washer

Page 69

IV-22

(2) Remove the MP extension tray from the MP tray cover by bending the former.

Figure 4.43

1.25 MP Tray ASSY

(1) Remove the MP tray ASSY from the MP tray cover by bending its bosses.

Figure 4.44

(2) Remove the 2 fixing bushes. (3) Remove the MP tray ASSY.

Figure 4.45

MP extension tray

MP tray cover

Boss

MP tray ASSY

MP tray cover

MP tray ASSY

Fixing bushes

Page 70

IV-23

(4) Remove the MP tray ASSY from the MP release plate bending its bosses.

The MP tray can be easily removed if it is slanted.

Figure 4.46

1.26 Paper Path Separation Plate, Paper Path Separation Film

(1) Remove them from the Paper feed guide lower by bending them.

Figure 4.47

1.27 Latch

(1) Remove the latch from the Paper feed guide upper by releasing the 2 hooks.

Figure 4.48

Paper feed guide upper

Hook

Latch

Hook

Boss

MP tray ASSY

Boss

MP release plate

Paper feed guide lower

Paper path separation platePaper path separation film

Page 71

IV-24

1.28 Fixing unit (for both 115V and 230V, the only difference is the Halogen heater)

(The fixing unit can be disassembled even after removing the Rear cover ASSY in section 1.6). (1) Release the hook of the heater lead wire connector (2P) by pinching the connector

and pull it out upward (to remove it from the low-voltage power supply ASSY). (2) Pull out the Fixing PCB connector (4P) to the rear (

(3) Loosen the 2 screws which are securing from the rear, and remove the fixing unit

by pulling it to the rear.

Figure 4.49

(4) Take off the Halogen heater by removing 2 screws at the both side, remove the

Halogen heater.

Figure 4.50

Note: Do not use the electric driver as the Halogen heater is easy to break.

Do not touch the Halogen heater glass. If finger prints are on it, clean it with a cloth dampen with iPA alcohol. When reassembling, make sure;

- The terminal of the heater lead wire connector (2P) should be placed over the terminal of the Halogen heater.

- The wire bridge between the Halogen heater and its terminal must be up.

Connector (4P)

Screw

Connector (2P)

Screw

Heater lead wire

Fixing unit

Halogen heater

Screw

Fixing unit cover

Page 72

IV-25

(5) Rremove the Thermistor lead wire connector (2P) of the Fixing PCB (see Figure

4.51). (6) Detach the wire from the hooks of the Fixing unit chassis. (7) Loosen 4 screws and remove the Fixing unit cover. Note: When removing the Fixing unit cover, the Thermistor cleaner ASSY and the spring

come off from the Fixing unit cover. Insert the Thermistor cleaner ASSY together with the spring into the correct possition first, and start reassembling. See Figure

4.50b.

Figure 4.51

Figure 4.52

Screws

Fixing unit chassis

Fixing unit cover

Hooks

Screws

Thermistor cleaner ASSY

Spring

Page 73

IV-26

(8) Loosen a screw and remove the Fixing PCB ASSY.

Figure 4.53

(9) Release the left hook and take off the Paper delivery actuator.

Figure 4.54

(10)

1) Remove the retaining rings (on both sides).

2) Remove the HR gear, loosen the screw and remove the spring washer, remove

the left and right HR bearings and the heat roller by sliding it.

Figure 4.55

Screw

Fixing PCB ASSY

Connector (2P)

Paper delivery actuator

Fixing unit cover

Thermistor

Screw

Retaining rin

Spring washer

Retaining ring

HR gear

Heat roller

HR bearing

Page 74

IV-27

3) Remove the Pressure roller spring and Pressure roller bearing on both sides, and

the Pressure roller.

Note: Do not use the electric driver to loosen/secure the screw as the plastic bush is

easy to break.

Figure 4.56

< Reassembly > Using the Release spacer L & R may help to assemble springs.

1.29 Transfer Unit

(1) Loosen a screw. (2) Release the 3 right hooks, (see Figure 4.57) lift the right part of the unit (

) and

slide it to the right (

) (See Figure 4.56)to take off the left part from the main

chassis L. Remove the transfer unit from the body by lifting the former.

Figure 4.57

Pressure roller bearing

Pressure roller

Fixing unit chassis

Pressure roller spring

<Right>

Transfer unit

Screw

Main chassis L

Page 75

IV-28

(3) Open the transfer base hook and take off the left bearing (white) from the hook

(

). Lift the left side (B), slide it to the left (C) and take off the roller shaft from

the right bearing (black) (

(4) Remove the transfer roller ASSY.

Caution: Do not touch the sponge rubber roller when replacing the transfer roller (the

roller with hand grease or clasped too strongly may result in poor printing quality).

Figure 4.58

1.30 DC Gear Holder ASSY

(1) Remove the DC motor connector, then remove the Paper delivery holder spring. (2) Loosen the 4 screws and remove the DC gear unit from the chassis. (3) Remove the Paper delivery gear ASSY, the gears, the Gear 48 spring, and the

washer.

(4) Loosen the 3 screws and remove the DC motor ASSY from the gear holder.

Figure 4.60Figure 4.59

3 Hooks

Transfer roller ASSY

Transfer base ASSY

PS switch wire

Paper delivery holder sprin

4 screws

DC gear unit

Remote switch

Gear 28

DC gear holder ASSY

Gear 24/72

Washer

Gear 21

Connector

3 screws

Gear 39

Gear 20/50

Gear 48 spring

Gear 48

Paper delivery gear ASSY

Gear 22/55

DC motor ASSY

Page 76

IV-29

1.31 PS Switch Wire, Remote Switch

(1) Pull out the PS switch wire from the remote switch and the switch attachment.

Lift slightly the wires when pulling them out. This is in order to release the chassis caught at 2 places.

(2) Remove the remote switch from the chassis.

1.32 High-Voltage Power Supply PCB ASSY

(1) Release the 2 hooks at the bottom of the LV duct and slid it towards the left. Lift it

upwards to remove.

(2) Remove the LV fan.

Figure 4.63

Figure 4.62Figure 4.61

Switch attachment

PS switch wire

Remote switch

Chassis

Remote switch

LV fan

LV duct

Page 77

IV-30

(3) Loosen the 2 screws and remove the connector. (4) Hold the head of 2 resin spacers and lift this side of PCB (

(5) Slide the PCB to the opposite side (

Figure 4.64

1.33 Low-Voltage Power Supply PCB ASSY

(1) Be sure to remove the heat insulation cover before removing the low-voltage

power supply block.

Figure 4.65

Heat insulation cover

Hook

Heat insulation cover

Resin spacers

High-voltage power supply PCB ASSY

The PCB can be detached without removin

this

Screws

Connector

Page 78

IV-31

(2) Remove the PS switch wire. (3) Loosen the 2 screws with the spring washer on the right side. (4) Loosen the 4 screws with the spring washer on the Low-voltage power supply

PCB.

(5) Disconnect the LV harness 8P.

Figure 4.66

1.34 Toner Cartridge (EP-ED HC Cartridge)

(1) Open the Toner cartridge lid and pull out the toner cartridge.

Figure 4.67

EP-ED HC

cartridge

Screw

PS switch wire

Screw

Low-voltage power suppl

PCB ASSY

LV harness 8P

Page 79

IV-32

1.35 Paper Tray

(1) Release the roller holder fixing pawl and remove the roller holder by pulling it out

upward. (2) Remove the roller. (3) Remove the Separation pad ASSY (pull it out by turning it).

Figure 4.68

Figure 4.69

Roller

Roller holder

Paper tray (A4 size)

Roller holder fixing pawl

Separation pad ASSY and spring

Earth spring

Paper stopper

Paper tray (legal / letter size)

Page 80

V-1

CHAPTER V MAINTENANCE AND SERVICING

1. PERIODICAL REPLACEMENT PARTS

Periodical replacement parts are the parts to be replaced periodically to maintain product quality at same level (in other words the parts which would affect the product greatly if they lost their function even if they are not damaged or there is no change in their appearance.) It is recommended to replace such parts on the occasion of a periodical service which is carried out before or after the specified number of sheets are printed, whichever more immediate to that time.

2. CONSUMABLE PARTS STANDARD ENDURANCE TABLE

The table below shows the suspected mean life (in terms of number of sheets) of the consumable parts, that is the parts which subject to deterioration or damage, should be replaced at least once during the period of warranty of the product only when the parts have such a failure.

Table 5.1

No. Description Part No. Qty Service life Remarks

1 Fixing unit UH1886001 1 100,000 pages 115V PART LIFE=100K

Fixing unit UH1887001 1 100,000 pages 230V PART LIFE=100K

2 Paper pick-up roller ASSY 3

Paper pick-up roller ASSY 5

UH2821001 UH1494001

11100,000 pages PART LIFE=100K

3 Separation pad ASSY

Separation pad ASSY W

UH2393001 UH1500001

11100,000 pages PART LIFE=100K

4 Transfer roller ASSY A UH1834001 1 100,000 pages PART LIFE=100K 5 Laser unit UH1885001 1 200,000 pages PART LIFE=200K

Note: The above table shows only estimated value, so these value are subject to

change without prior notice.

When every 100,000 pages are printed, the printer prompts “73 MAINTENANCE 1” on the LCD panel for the replacement of the Fixing unit, the Paper pick-up roller ASSY, the Separation pad ASSY and the Transfer roller ASSY A.

When every 200,000 pages are printed, the printer prompts “73 MAINTENANCE 2” on the LCD panel for the replacement of the Laser unit.

After replacing the periodical replacement parts, the parts life counter for them MUST BE RESET with the following procedure.

[ Reset procedure ] (1) Take the printer off-line. (2) Press CONT + SEL key. (3) Press

or to get “PART LIFE 100K RESET”, or “PART LIFE 200K RESET”.

(4) Press SET key to reset the parts life counter.

PR98191

Page 81

V-2

3. LIST OF STANDARD TOOLS

The standard tool set required for servicing the printer is as listed below. These tools are commercially available on the market.

Table 5.2

No. Description Remarks

1 2 3 4 5

Tool box Lead cable Feeler gauge Compression spring scale (0 - 1kg) Phillips screwdriver

For checking cassette spring strength

M4, M5 6 7 8 9

Phillips screwdriver Phillips screwdriver Phillips screwdriver Flat-blade screwdriver Precision flat-blade screwdriver

M3, M5

M4, M5

11 12 13 14 15

Allen wrench set File, fine Allen (hex) screwdriver Diagonal-cutting pliers Needle-nose pliers

16 17 18 19 20

Pliers Snap-ring pliers, ext. 19 - 30 mm Crimper Tweezers

Ruler 21 22 23 24 25

Mallet, plastic head

Brush

Penlight

Bottle, plastic

Solder 26 27 28 29 30

Desoldering wick

Oiler

Jar, plastic

Digital logic tester

Digital multimeter 31 32

Soldering iron

Digital memory scope or syncroscope

(100 MHz or over)

ROM remover

Page 82

V-3

4. LIST OF LUBRICANTS AND CLEANERS

Table 5.3

No. Material name Components Use Remarks

1 Alcohol ethyl

(pure or denatured) or isopropyl (pure or denatured)

OH, (CH

)

CHOH

Cleaning of plastic, rubber, and external parts

• Purchase locally

2 MEK

(methyl ethyl ketone)

CO-C

Cleaning for oil and toner stains

• Purchase locally

• Highly flammable;

keep away from flame

3 Lubricating oil

(silicon grease KS64F)

For fuser

• Tool No. ZX-43D

• Equivalent oil may be used

4 Lubricating oil

(Moly kote EM-30L)

For drive mechanism

• Tool No. ZX-43N

• Equivalent oil may be used

Page 83

VI-1

CHAPTER VI TROUBLESHOOTING

1. INTRODUCTION

1.1 Initial Check

(1) Operating environment

Check if:

1) The source voltage stays within ±10% from the rating voltage shown on the rating label.

2) The printer is installed on a solid, level surface.

3) The room temperature is maintained between 10°C and 32.5°C. The relative humidity is maintained between 20% and 80%.

4) The printer is not exposed to ammonia fumes or other harmful gases.

5) The printer is not located in a hot or humid area (such as near water or a humidifier), in a cold place (such as outlet of an air conditioner), near open flames or in a dusty place.

6) The printer is not exposed to direct sunlight.

7) The room is well-ventilated.

(2) Printer paper

Check if:

1) A recommended type of print paper is being used (if the paper is too thick or too thin, or tends to curl, paper jams or paper feed problems may occur, or prints may be blurred).

2) The print paper is damped. [If so, use fresh paper, and check whether the print quality improve or not.]

(3) Consumables

Check if:

1) The message "16 TONER EMPTY" is not shown on the status display when a cartridge is installed in the printer. [If the message is displayed, replace the cartridge with a new one. If blank spots occur on prints, take out the EP-ED cartridge and slowly rock it to distribute the toner evenly.]

(4) Others

Check if: The transfer guide and feed guide are clean. [If not, clean them with a damp cloth.] Condensation: When the printer is moved from a cold room into a warm room in cold weather, condensation may occur inside the printer, causing various problems as below:

1) Condensation on the optical surfaces such as the scanning mirror, lenses, the reflection mirror and the protection glass may cause the print image to be light.

2) If the photosensitive drum is cold, the electrical resistance of the photosensitive layer gets high, making it impossible to obtain a correct contrast in printing.

3) Condensation on the pick-up guide and feed guide plates may cause paper feed troubles.

If condensation has occurred, wipe the effected units or parts with a dry cloth. If an EP-ED cartridge is unsealed soon after moved from a cold room to a warm room, condensation may occur inside the cartridge, which may cause incorrect image. Instruct the user to allow the cartridge to come to room temperature before unsealing it. This will take one to two hours.

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VI-2

1.2 Basic Procedure

If a malfunction or incorrect print is appeared, make an initial check, then follow the basic procedure below: (1) Check the status display. If any message is shown, see Section 4 for

troubleshooting.

(2) If an incorrect image is found, see Section 3.1 to determine the defect type and

Section 3.2 for image troubleshooting.

2. TEST PRINTING AND MECHANICAL CHECK

2.1 Test Printing

If an image problem occurs, follow the procedure below to produce a test print.

1) Enter the offline mode.

2) Press the SHIFT and TEST switches simultaneously, so the printer enters the

test print mode.

3) Press the

or switch to appear the message "TEST PRINT" then press the

SET switch. The message "05 TEST PRINT" will appear on the status display of the control panel and the DATA lamp will come on. Then, the printer will produce the test print.

4) Determine the image trouble type and see Section 3 for troubleshooting.

TEST PRINT

Figure 6.1

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VI-3

3. IMAGE DEFECTS

3.1 Image Defect Examples

I-1 Light I-2 Dark I-3 Completely blank I-4 All black

I-6 Dirt on back of paper

I-7 Black vertical streaks I-8 Black and blurred

vertical stripes

I-10 Black and blurred horizontal stripes

I-11 Dropout I-12 White vertical

streaks

I-13 Faulty

registration

I-14 Poor fixing

I-5 Polka dots

I-9 Black and thin horizontal streaks

Figure 6.2

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VI-4

3.2 Troubleshooting Image Defects

I-1 Light

Possible cause Step Check Result Remedy

Toner shortage 1 Does printed image improve when the

EP-ED HC cartridge is replaced?

Yes Replace EP-ED HC

cartridge. ECONOMY mode

2 Is the ECONOMY mode active? Yes Cancel the ECONOMY

mode. Printing density setting

3 Does printed image improve when printed

density setting is changed on the control panel?

Yes Adjust the proper setting

on the control panel.



4 During a printing, open the toner cartridge lid

in the printer and pull out the EP-ED HC cartridge. Open the drum shutter of the EP-ED HC cartridge and check the toner image on the drum. Is the toner image before transfer is light?

Yes Go to the Step 9.

Paper failure 5 Does the print quality improve when fresh

paper is used?

Yes Use recommended paper.

Transfer roller failure

6 Does the print quality improve when print is

made with transfer roller changed?

Yes Clean the transfer roller

[Use dry lint-free paper

(producing little paper

dust) to clean the

transfer roller. Never use

solvents] and, if dirt

subsists, replace the

transfer roller assy. Transfer input signal error

7 Do the pins 7 and 8 of the connector P6 on the

main PCB have the following value respectively when a sheet of paper is fed from the MP tray? P6-7 pin (HVT2) --- Change in voltage from 15V approx. to 0V about 1 second after paper feeding. P6-8 pin (HVT3) --- Change in voltage from 9V approx. to 0V just when the voltage at the 7 pin changes from 0V to 15V.

No Replace the main PCB

assy or the harness.

Dirt on power supply terminal

8 Clean the transfer roller right end bearing, the

check continuity between the transfer roller power supply spring and the terminal

No Clean the contact to

assure the continuity.

Failure in the transfer highvoltage circuit

of the high-voltage transfer unit. Is there continuity?

Yes Replace the high-voltage

power supply assy.

Insufficient LD light

9 Does print quality improve when the laser unit

is improved?

Yes Replace the laser unit or

the harness.

Continued to the following page

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VI-5

Possible cause Step Check Result Remedy Development input signal error

10 Do the pins 3, 4 and 5 of the connector

P6 on the main PCB have the following value respectively when a sheet of paper is fed from the MP tray? P6-3 pin (DBAC) --- Change in voltage from 6V approx. to 0V just when a sheet of paper is fed from the registration unit. P6-4 pin (DBDC) --- Change in voltage from 9V approx. to 0V just when a sheet of paper is fed from the registration unit. P6-5 pin (DNSTY) --- Change in voltage to

2.5V just when a sheet of paper is fed.

No Replace the laser unit or

the harness.

Dirt on power supply terminal

11 Is there any dirt on the cartridge side

development terminal of the transfer unit and on the terminal of the high-voltage power

No Clean the contacts to

assure the continuity.

Failure in the development high-voltage circuit

supply development unit? (is there continuity between them?)

Yes Replace the high-voltage

power supply PCB assy.

I-2 Dark

Possible cause Step Check Result Remedy Density setting 1 Does printed image improve when density

setting is changed on the control panel?

Yes Adjust the proper setting

on the control panel. EP-ED HC cartridge

2 Does printed image improve when the EP-ED

HC cartridge is replaced?

Yes Replace the EP-ED HC

cartridge. Dirt on the grounding terminal

3 Does printed image improve when continuity

is improved by cleaning the EP-ED HC cartridge grounding terminal and the printer unit grounding terminal?

Yes Clean the contacts to

assure the continuity.

Charging input signal error

4 Do the pins 1, 2 and 5 of the connector P6

on the main PCB have the following value respectively when a sheet of paper is fed from the MP tray? P6-1 pin (HV1AC) --- Change in voltage from 6V approx. to 0V just when a sheet of paper is fed. P6-2 pin (HV1DC) --- Change in voltage from 9V approx. to 0V just when a sheet of paper is fed. P6-5 pin (DNSTY) --- Change in voltage to

2.5V just when a sheet of paper is fed.

No Replace the main PCB

assy or the harness.

Dirt on power supply terminal

5 Is there any dirt on the cartridge side charging

terminal of the transfer unit and on the terminal of the high-voltage power supply charging unit?

No Clean the terminal to

assure the continuity.

Failure in the charging highvoltage circuit

(is there continuity between them?) Yes Replace the high-voltage

power supply PCB assy.

Page 88

VI-6

I-3 Completely blank

Possible cause Step Check Result Remedy EP-ED HC cartridge

1 Does printed image improve when the EP-ED

HC cartridge is replaced?

Yes Replace the EP-ED HC

cartridge.

Development input signal error

2 Do the pins 3, 4 and 5 of the connector?

2.5V just when a sheet of paper is fed.

No Replace the main PCB

assy or the harness.

Failure in power supply terminal

3 Is there any dirt on the cartridge side

development terminal of the transfer unit and on the terminal of the high-voltage power supply development unit? (is there continuity between them?)

No Clean the terminal to

assure the continuity.

LD failure 4 Does print quality improve when the laser

unit is improved?

Yes Replace the laser unit or

the harness. Failure in development high-voltage circuit

No Replace the high-voltage

power supply PCB assy.

I-4 All black

Possible cause Step Check Result Remedy Beam detection error

1 Is the printer hung up with the PRINT message

remaining on the display even after a printing when only a copy is printed?

Yes Replace the laser unit or

the harness.

EP-ED HC cartridge

2 Does printed image improve when the EP-ED

HC cartridge is replaced?

Yes Replace the EP-ED HC

cartridge.

Charging input signal error

3 Do the pins 1 and 2 of the connector P6 on the

main PCB have the following value respectively when a sheet of paper is fed from the MP tray? P6-1 pin (HV1AC) --- Change in voltage from 6V approx. to 0V just when a sheet of paper is fed. P6-2 pin (HV1DC) --- Change in voltage from 9V approx. to 0V just when a sheet of paper is fed.

No Replace the main PCB

assy or the harness.

Dirt on power supply terminal

4 Is there any dirt on the cartridge side charging

terminal of the transfer unit and on the terminal of the high-voltage power supply charging unit?

No Clean the contact to

assure the continuity.

Failure in the charging highvoltage circuit

LD failure

(is there continuity between them?) Yes Replace the high-voltage

power supply PCB assy and, if the problem is not resolved, replace the laser unit or the harness.

Page 89

VI-7

I-5 Polka dots

Possible cause Step Check Result Remedy Failure in staticcharge eliminator

1 Is there any dirt on the static-charge

eliminator?

Yes Clean the static-charge

eliminator.

Static-charge eliminator grounding failure

2 Is there continuity between the static-charge

eliminator and the chassis?

Yes Ensure the grounding of

the static-charge eliminator.

Dirt on the transfer roller

3 Does print quality improve when the transfer

roller is replaced?

Yes Clean the transfer roller

[Use dry lint-free paper (producing little paper dust) to clean the transfer roller. Never use solvents] and, if the dirt remains, replace the transfer roller assy.

I-6 Dirt on back of paper

Possible cause Step Check Result Remedy Dirt on the PF guide

1 Is there any dirt on the back of the paper feed

guide and the jam remove cover near the static-charge eliminator?

Yes Clean the PF guide or the

jam remove cover.



2 Open the toner cartridge lid in the printer, pull

out the EP-ED HC cartridge and remove the paper in the printer. Is there already dirt on the back of the sheet thus removed?

No Go to Step 6.

Dirt on the transfer roller

3 Is there any dirt on the transfer roller? Yes Clean the transfer roller

and, if the dirt remains, replace the transfer roller

assy. Transfer input signal error

4 Does the voltage at the 6 pin (HVT1) of the

connector P6 on the main PCB change from 9V to 0V for about 0.8 seconds?

No Replace the main PCB

assy or the harness.

Dirt on power supply terminal

5 Clean the transfer roller right end bearing, the

check continuity between the transfer roller power supply spring and the terminal of the

No Clean the contact to

assure the continuity.

Failure in the transfer highvoltage circuit

high-voltage transfer unit. Is there continuity? Yes Replace the high-voltage

power supply PCB assy.

Dirt the fixing guide

6 Is there any dirt on the fixing unit inlet guide? Yes Clean the fixing unit inlet

guide.

Fixing roller grounding

7 Are the upper and lower rollers of the fixing

unit securely connected to the chassis via the

No Ensure the grounding.

failure Fixing unit failure

diode? Yes Replace the fixing unit.

Page 90

VI-8

Black vertical streaks or Blurred vertical line

Possible cause Step Check Result Remedy EP-ED HC cartridge

Fixing unit

1 During a printing, open the toner cartridge lid

in the printer and pull out the EP-ED HC cartridge. Open the drum shutter of the EP-ED HC cartridge

Yes Replace the EP-ED HC

cartridge.

damaged and check the toner image on the drum.

Are there vertical stripes on the drum?

No Replace the fixing unit.

I-9 Black and thin horizontal streaks

Possible cause Step Check Result Remedy Beam detection error



Replace the laser unit or the harness and, if the problem is not resolved, replace the main PCB assy.

I-10 Black and blurred horizontal stripes

Possible cause Step Check Result Remedy Drum or charging roller failure

1 Do stripes appear at 95 mm or 38 mm

interval?

Yes Replace the EP-ED HC

cartridge.

Fixing unit failure

2 Do stripes appear at 80 mm interval? Yes Replace the fixing unit.

I-7

I-8

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VI-9

I-11 Dropout

Possible cause Step Check Result Remedy Paper failure 1 Is recommended paper used? No Use recommended paper. Paper soaked 2 Is paper soaked? Yes Store the paper in packing

paper to keep it from

soaking. EP-ED HC cartridge

3 Does printed image improve when the EP-ED

HC cartridge is replaced?

Yes Replace the EP-ED HC

cartridge. Transfer roller failure

4 Is there any dirt on the transfer roller or is it

deformed?

Yes Clean or replace the

transfer roller assy. Transfer input signal error

5 Do the pins 7 and 8 of the connector

P6 on the main PCB have the following value respectively when a sheet of paper is fed from the MP tray? P6-7 pin (HVT2) --- Change in voltage from 15V approx. to 0V about 1 second after a sheet of paper is fed. P6-8 pin (HVT3) --- Change in voltage from 9V approx. to 0V when the voltage at the pin 7 changes from 0V to 15V.

No Replace the main PCB

assy or the harness.

Dirt on power supply terminal

6 Clean the transfer roller right end bearing, the

check continuity between the transfer roller power supply spring and the terminal of the

No Clean the contact to

assure the continuity.

Failure in the transfer highvoltage circuit

high-voltage transfer unit. Is there continuity? Yes Replace the high-voltage

power supply PCB assy.

I-12 White vertical streaks

Possible cause Step Check Result Remedy

Toner bias 1 Do white vertical stripes appear like a band? Yes Rock the cartridge, set it

again in the printer and

check again the print

quality. Drum damage 2 Does print quality improve when the EP-ED

HC cartridge is replaced?

Yes Replace the EP-ED HC

cartridge. Transfer roller failure

3 Is the transfer roller damaged or deformed? Yes Replace the transfer roller

assy. Dirt on the reflecting mirror

4 Is the problem solved when the laser unit is

replaced?

Yes Clean the reflecting mirror

with a cleaning tip or

replace the laser unit.

Page 92

VI-10

I-13 Faulty registration

Possible cause Step Check Result Remedy Top margin setting error

1 Does self test printing have no problem? Yes Check again the top

margin setting in the

printing data. Paper load in the cassette

2 Is over-amount of paper than specified load

on the cassette?

Yes Reduce the paper load

below the specified limit. Paper failure 3 Does print quality improve when