Ricoh FAX2500L SPECIFICATIONS 3000

FAX3000L

SERVICE MANUAL

WARNING

DANGER

INVISIBLE LASER RADIATION WHEN OPEN AVOID DIRECT

EXPOSURE TO BEAM

DANGER

RAYON LASER INVISIBLE

LORS DE L’OUVERTURE

EVITER L’EXPOSITION DIRECTE

VORSICHT

Unsichtbare Laserstrahlung

unter dieser Abdeckung. Nicht

in den laserstrahl blicken.

PELIGRO

RADIACION LASER INVISIBLE

AL ABRIR. EVITAR LA

EXPOSICION DIRECTA AL HAZ

THIS MACHINE CONTAINS A LASER BEAM GENERATOR. LASER

BEAMS CAN CAUSE PERMANENT EYE DAMAGE. DO NOT OPEN

THE LASER UNIT OR LOOK ALONG THE LASER BEAM PATH

WHILE THE MAIN POWER IS ON.

Lithium Batteries (Memory Back-up) CAUTION:

The danger of explosion exists if a battery of this type is incorrectly replace d. Replace only with the same or an eq uiva lent type recommended by the manufacturer. Discard used batteries in accordance with the manu fa ctu rer’s instructions.

OVERALL MACHINE INFORMATION November 30th, 1991 SPECIFICATIONS

1. OVERALL MACHINE INFORMATION

1.1. SPECIFICATIONS

Type

Desktop transceiver

Circuit

PSTN, PABX

Connection

Direct couple

Document Size Length: 105 - 1200 mm

[4.1 - 47.2 ins] Up to 100 m [328 ft] after adjustment Width: 148 - 304 mm

[5.8 - 12.0 ins] Thickness: 0.05 to 0.2 mm

[2 to 8 mils]

Document Feed

Automatic feed, face down

ADF Capacity

50 sheets (using 80 g/m

Scanning Method

Flat bed, with CCD

Maximum Scan Width

256 mm [10.1 ins] ± 1%

Scan Resolution Main scan: 8 dots/mm [203 dpi] Sub scan:

Standard - 3.85 lines/mm [98 lpi] Detail - 7.7 lines/mm [196 lpi] Fine - 15.4 lines/mm [392 lpi]

Memory Capacity ECM: 128 kbytes (double buffer) SAF: 256 kbytes (14 pages), with

optional extra 1 Mbyte or 2 Mbytes (max 71 or 128 pages respectively)

Compression

MH, MR, EFC, MMR, SSC Storage to SAF memory for tx: MH MMR only with ECM

Modulation

V.29 (QAM), V.27ter (PHM), V.21 (FM)

Protocol

Group 3 with ECM

paper)

Data Rate

9600/7200/4800/2400 bps; automatic fallback

I/O Rate

With ECM: 0 ms/line Without ECM: 5, 10, 20, or 40 ms/line

Transmission Time

10 s at 9600 bps (G3 ECM using memory) for a CCITT #1 test document (Slerexe letter) using standard resolution

Printing System

Laser printing, using the Ricoh CS (Compact Seamless) Engine, plain paper, dry toner

Paper Size Standard Cassette

Europe: A4, A5 Asia: A4, A5, F, F4

Lower Cassette

Europe: A4, A5 Asia: A4, A5, F, F4, B4

Maximum Printout Width

210 mm [8.3 ins]

Maximum Printer Resolution Main scan: 16 dots per mm [406 dpi] Sub scan: 15.4 lines/mm [392 lpi]

Power Supply

220 - 240 Vac, 50 Hz

Power Consumption (Base Machine Only) Standby: 35 W Transmit: 50 W Receive: 200 W Copying: 270 W

Operating Environment Temperature: 17 - 28 °C [63 - 82 °F] Humidity: 40 - 70 %Rh

Dimensions (W x D x H)

496 x 459 x 293 mm [19.5 x 18.1 x 11.5 ins] Excluding handset, trays, and optional units

Weight

19 kg [41.8 lbs] Excluding handset, trays, and optional units

1-1

November 30th, 1991 OVERALL MACHINE INFORMATION

FEATURES

1.2. FEATURES

KEY: O = Used, X = Not Used,

A = With optional memory only, B = With lower cassette only, G = Not used in Germany, S = Service mode in some countries

Equipment

ADF O Bar code reader X Built-in handset X Cabinet X Connection for ans. machine X Connection for handset O Cutter X Handset (option only in Europe) O Hard disk X Magnetic card reader X Manual feed mechanism O Marker O Microphone X Monitor speaker O Remaining memory indicator O Speakerphone X

Video Processing Features

Contrast O Halftone (Basic & Error Diffusion) O MTF O Reduction O Resolution O Smoothing to 16 x 15.4 l/mm O

Communication Features - Auto

Automatic fallback O Automatic redialling O Confidential reception A Dual Access O Substitute reception O Transmission Reserve X

Communication Features -

User Selectable

Action as a transfer broadcaster X AI Redial O Alternative Destination O Answering machine X Authorized Reception O Auto-answer delay time X Auto dialling (pulse or DTMF) O Auto Document O Automatic Voice Message X Auto-note X Batch Transmission (max 5 files) A Broadcasting O Chain Dialling O Confidential ID Override O Confidential Transmission O Forwarding (4 stations) A Free Polling O Groups (7 groups) O Hold X Immediate Redialling O Immediate transmission O Keystroke Programs O Mailbox X Memory transmission (this is the

default mode) Notify X On Hook Dial O (G) Page Count O Personal Codes O Personal Codes with Conf ID O Polling Reception O Polling Transmission O Quick Dial (32 stations) O Reception modes (Fax, Tel, Reduction O Remote control features X Remote Transfer X Restricted Access (10 codes,

without cards) Secured Polling O Secured Polling with Stored ID

Override Send Later O

Auto) O

1-2

OVERALL MACHINE INFORMATION November 30th, 1991 FEATURES

Communication Features -

User Selectable

Silent ringing detection X Speed Dial (100 stations) O Telephone Directory O Tonal Signal Transmission O Transfer Request O Transmission Deadline X Turnaround Polling X Voice Request (immed. tx only) O

Communication Features -

Service Selectable

AI Short Protocol X Auto-reduction override option O Busy tone detection O Closed Network (tx and rx) O Continuous Polling Reception O Dedicated tx parameters O ECM O EFC O MV1200 compatibility X Page retransmission O Page separation mark O Polling tx file lifetime in the SAF O Protection against wrong conn. O Resol’n stepdown override option X Short Preamble O Well log O

Other User Features

Auto Service Call O Center mark O Chequered mark X Clearing a memory file O Clearing a polling file O Clock O Confidential ID O Copy mode O Counters O Dialled number check X Direct entry of names O Function Programs O ID Code O Label Insertion O Language Selection O LCD contrast control Service

Memory Lock A Memory Lock ID A Modifying a memory file X Multi Sort Document Reception A Multicopy mode A Night Timer O Own telephone number O Printing a memory file O RDS on/off O Reception Mode Switching Timer X Reception Time (non-memory rx

only) Remote ID X Reverse Order Printing A RTI, TTI, CSI O (S) Speaker volume control O Specified Cassette Selection B Substitute reception on/off O Telephone line type O (S) TTI on/off O User Function Keys X User Parameters O Wild Cards O

Reports - Automat ic

Charge Control Report X Communication Failure Report O Confidential File Report O Error Report O Memory Storage Report O Mode Change Report X Polling Clear Report O Polling Reserve Report O Polling Result Report O Power Failure Report O Journal O Transfer Result Report X Transmission Result Report O

Reports - User-initiated

Authorized Reception List O Charge Control Report X File List O Forwarding List A Group List O Personal Code List O Program List O

1-3

November 30th, 1991 OVERALL MACHINE INFORMATION

FEATURES

Reports - User-initiated

Quick Dial List O Specified Cassette Selection List B Speed Dial List O Journal O Transmission Status Report X User Function List X User Parameter List O

Service Mode Features

Back-to-back test O Bit switch programming O Buzzer test O Cable equalizer (rx only) O Comm. parameter display O DTMF tone test O Echo countermeasure O Error code display O LCD contrast adjustment O Memory file forwarding O Memory file printout (all files) O Modem test O NCU parameters O Operation panel test O Printer mechanism test X Printer test patterns O Programmable attenuation X Protocol dump list O RAM display/rewrite O RAM dump O Ringer test X Scanner lamp test O Scanner mechanism test O Sensor initialization X Serial number O Service monitor report O Service station number O System parameter list O Technical data on the Journal O Thermal head parameters X Transmission Status Report X

Memory Files

Max. number of files: 100 Max. number of stations/ file : 14 2 Max. number of stations ove rall: 299 Max. number of pages overall: 200 (including pages stored as A uto Documents)

1-4

OVERALL MACHINE INFORMATION November 30th, 1991 COMPONENT LAYOUT

1.3. COMPONENT LAY OUT

1.3.1. Mechanical Components

16 17

20 21 22 23

6789

1. R2 Rollers Feed the document through the scanner.

2. Exposure Glass Exposes the original to light from the xenon lamp.

3. R1 Rollers Feed the document through the scanner.

4. Separation Roller Allows one page into the scanner.

5. Document Feed Roller Feeds the document into the scanner.

6. Pick-up Roller Picks up pages of the document from the document table.

7. Toner Cartridge This supplies toner to the development unit. It is part of the CTM (Cleaning/Toner Magazine).

8. Charge Corona Unit This applies a charge to the master at the start of the print cycle.

9. Quenching Lamp This removes excess charge from the master at the end of the print cycle.

10. Thermistor This measures the temperature in the fusing unit.

11. Hot Roller Heat from this roller fuses the toner to the copy paper.

1-5

November 30th, 1991 OVERALL MACHINE INFORMATION

COMPONENT LAYOUT

12. Hot Roller Strippers These take the paper off the hot roller after fusing.

13. Copy Feed-out Rollers These feed the paper out of the printer.

14. Pressure Roller (Fusing) This applies pressure to the paper during the fusing process.

15. Cleaning Unit/Used Toner

Tank

16. Transfer Corona Unit This applies a charge to the paper to pull the toner off

17. Master Belt Also known as the CS (Compact Seamless) Engine.

18. Registration Roller This carries out the registration process.

19. Registration Sensor This detects when paper is approaching the registration

20. Development Roller This roller applies toner to the latent image on the

21. Toner Supply Bar This feeds toner to the development roller.

22. Toner Mixing Bar This stirs up the toner in the development unit, so that it

23. Upper Relay Rollers These feed paper from the upper cassette into the

24. Lower Relay Rollers These feed paper from the lower cassette into the

25. Lower Paper Feed Roller This feeds paper out of the lower cassette.

26. Lower Paper Separation

Roller

27. Lower Paper Pick-up

Roller

28. Upper Paper Feed Rollers These pick up the top sheet of paper from the stack in

29. Focusing Lens This focuses the laser beam onto the master belt.

30.

Fθ Lenses

31. Hexagonal Mirror This passes the laser beam across the master belt.

32. CCD (Charge Coupled

Device)

This removes excess toner from the master after image transfer and stores it. It is part of the CTM (Cleaning/Toner Magazine).

the master and onto the copy paper.

The latent image is written to this organic photoconductor belt.

roller.

master belt.

does not collect into lumps.

printer.

This ensures that only one sheet of paper at a time leaves the lower cassette.

This picks up the top sheet of paper from the stack in the lower cassette and passes it to the feed roller.

the upper cassette and feed it into the printer.

These ensure that the thickness of the laser beam is uniform across the main scan.

This converts the light reflected from the document into an analog video signal.

1-6

567

OVERALL MACHINE INFORMATION November 30th, 1991 COMPONENT LAYOUT

1.3.2. Drive Components

1-7

November 30th, 1991 OVERALL MACHINE INFORMATION

COMPONENT LAYOUT

1. Tx Motor This stepper motor drives the scanner.

2. R2 Roller This feeds the original through the scanner.

3. Toner Supply Motor This dc motor drives the toner supply mechanism.

4. R1 Roller This feeds the original through the scanner.

5. Shutter Drive Gear This ensures that the shutter moves out of the document feed path at the correct time.

6. Toner Supply Gear (CTM) This ensures the supply of toner from the CTM into the development unit. It is part of the CTM.

7. Cleaning Brush Drive Gear This drives the cleaning brush in the CTM.

8. Hot Roller This fuses the toner to the copy paper.

9. Copy Feed-out Roller This feeds printouts out of the machine.

10. Pressure Roller This applies pressure to the copy paper in the fusing unit.

11. Registration Roller Drive

Gear

12. Upper Paper Feed Motor This drives the paper feed mechanism in the upper

13. Development Roller Drive

Gear

14. Upper Paper Feed Roller

Drive Gear

15. Master Belt Drive Gear This drives the master belt.

16. Paper Feed Clutch This transfers drive from the upper paper feed motor to

17. Toner Supply Gear

(Development)

18. Main Motor This brushless dc motor drives the master belt, fusing

19. Lower Paper Feed Motor This drives the paper feed mechanism in the lower

20. Lower Paper Feed Clutch This transfers drive from the lower paper feed motor to

This drives the registration roller.

cassette. This drives the development roller.

This drives the upper paper feed roller.

the upper paper feed mechanism. This ensures the collection of toner from the CTM, and

its distribution across the full length of the development unit.

unit, development unit, and cleaning unit.

cassette.

the lower paper feed mechanism.

1-8

OVERALL MACHINE INFORMATION November 30th, 1991 COMPONENT LAYOUT

1.3.3. Electrical Components

1-9

November 30th, 1991 OVERALL MACHINE INFORMATION

COMPONENT LAYOUT

Lower Cassette

Name Description No.

PCBs

FCU This board controls the machine. 11 MBU This board contains the system ROM and RAM for storing

system parameters such as bit switch settings and programmed

telephone numbers. SBU This board contains the CCD. 1 OP-PORT This board controls the operation panel. 37 NCU This board contains relays and switches for interfacing the

machine to the network and the handset. PSU This board supplies power to the machine. 3 LD Unit This board drives the laser diode. 10 PFU This board controls the lower paper feed unit. 44

MOTORS

Tx Motor This stepper motor drives the scanner. 34 Main Motor This dc motor drives the fusing unit, master belt, development

roller, and cleaning unit. Upper Paper

Feed Motor Lower Paper

Feed Motor Toner Supply Mo-

tor Hexagonal Mirror

Motor Ozone Fan This removes ozone-laden air from the vicinity of the master

This stepper motor drives the upper paper feed mechanism and

the registration roller.

This stepper motor drives the lower paper feed mechanism. 43

This dc motor drives the toner supply mechanism. 33

This high-speed dc motor drives the hexagonal mirror in the

laser printer optics.

unit, and filters out the ozone.

1-10

OVERALL MACHINE INFORMATION November 30th, 1991 COMPONENT LAYOUT

Name Description No.

CLUTCHES

Upper Paper Feed Clutch

Lower Paper Feed Clutch

SENSORS

Document Sensor This detects the presence of a document in the feeder. 36 Scan Line Sensor This detects when a page is approaching the auto shading

Document Width Sensor

Toner Near-end Sensor

Upper Paper Size Detector

Upper Paper End Sensor

Registration Sensor

Paper Feed-out Sensor

Front Cover Switch

CTM Sensor This detects when a CTM has been installed in the machine. 27 Lower Paper

Size Detector Lower Paper End

Sensor Lower Paper

Feed Sensor

INTERLOCK SWITCHES

Front Cover Interlock Switches

OTHERS

Speaker This allows the user to listen to the condition of the telephone

Xenon Lamp This lamp illuminates the document. 35 Xenon Lamp

Driver Charge Corona

and Quenching Lamp Unit

Transfer Corona Unit

Varistor This ensures that the charge given to the master by the charge

Marker This stamps a red circle on each page that is successfully fed

This transfers drive from the upper paper feed motor to the

paper feed roller in the upper cassette.

This transfers drive from the lower paper feed motor to the

paper feed roller in the lower cassette.

position.

This detects when a B4-width [10.1"] document has been

placed in the feeder.

This detects when the toner has almost run out. 17

This detects the paper size installed in the upper cassette. The

user must install the correct actuator.

This detects when the paper in the upper cassette has run out. 29

This detects when paper has arrived at the registration rollers. 21

This detects when the paper has been fed out of the printer. 24

This detects whether the front cover is open or closed. 23

This detects the paper size installed in the lower cassette. The

user must install the correct actuator.

This detects when the paper in the lower cassette has run out. 38

This sensor detects the presence of paper at the lower paper

feed roller.

If the front cover is open, these interlock switches interrupt the

+5VLD power supply for the laser diode and the +24VD power

supply for the power pack, motors, and other components.

line.

This drives the xenon lamp. 2

The charge corona unit charges the master belt at the start of

the print cycle. The quenching lamp removes excess charge

from the master belt at the end of the print cycle.

This pulls the toner off the master and onto the copy paper. 7

corona wire does not exceed -750 Volts.

through the scanner.

19, 20

1-11

November 30th, 1991 OVERALL MACHINE INFORMATION

COMPONENT LAYOUT

Name Description No.

Power Pack This supplies high voltages to the corona wires and the

development bias terminal. Fusing Lamp This fuses the toner to the paper. 6 Thermistor This monitors the temperature inside the fusing unit. 8 Thermostat This interrupts the ac power supply to the fusing lamp if the

temperature exceeds 400 °C. Lower Cassette

Indicator Panel

This contains indicators to show the status of the lower cassette. 40

1-12

OVERALL MACHINE INFORMATION November 30th, 1991 OVERALL MACHINE CONTROL

1.4. OVERALL MACHINE CONTROL

SBU

(CCD)

Scanner Sensors

Operation

Panel

NCU

CONTROL SIGNALS

Video Processing

Memory

Video

Processor

HandsetLine

Speaker

Modem AFE

CPU

PSU

Port

Scanner and Printer Drive

Components and Sensors

FCU

I/O

RS-232C

Interface

DATA AND ADDRESS BUS

ECM

Memory

MBU

Laser

Interface

RAMROM

Laser Diode Driver Main Scan Start Detector Interlock Switch

Page

Memory

SAF

Memory

The cpu on the FCU board controls the machine, as shown in the above drawing.

There is no modem board in the machine. The cpu performs the digital functions of a modem and carries out digital to analog conversion of facsimile data. There is a separa te an alog modem chip, called the Modem AFE, wh ich does the rest of the modem operations.

1-13

November 30th, 1991 OVERALL MACHINE INFORMATION

VIDEO DATA PATH

1.5. VIDEO DATA PATH

1.5.1. Transmission

Original

Reference: Group 3 Facsimile Manual, section 1-3-1

Xenon

Lamp

ECM

Memory

Line

Buffer

SAF

Memory

RAM

MBU

FIFO

Video

Processor

The following diagrams show the data path for this mod el.

CCD

Analog Signal

CPU

Modem (Digital)

MODEM

AFE

FCU

Modem

(Analog)

To the

Network

(via the NCU)

1.5.2. Reception

From the

Network

(via the NCU)

Reference: Group 3 Facsimile Manual, section 1-3-2

Line

Buffer

RAM

MBU

FCU

Memory

SAF

FIFO

Filter

HYBRID IC

Memory

ECM

Page

Memory

Laser Diode

Modem

(Analog)

Modem (Digital)

CPU

MODEM

AFE

Laser

Interface

Laser Diode

Driver

1-14

Copy Paper

OVERALL MACHINE INFORMATION November 30th, 1991 POWER DISTRIBUTION

1.6. POWER DISTRI BUTI O N

1.6.1. Distribution Diagram

AC Main

PSU

Power

AC Switching

Circuit

Fusing

Lamp

+24V

-12V

+24VS

+24VD

Scanner Sensors

+5V

Operation

Panel

+5V

+24VD

Lower Paper Feed Motor Lower Paper Feed Clutch

+24VD

PFU

+5V

+24VD

+5V

NCU

+5V +24VS

FCU

Regulator

- 5V

- 12V +12V

Regulator

+24VS

Sensors and

Indicators

FUSING UNIT

Thermistor

+5V

MBU

SAF Memory

+5V

SBU

+12V

+5V

Front Cover

Interlock Switch

Front Cover

Microswitch

+5V

+5VLD

LDDR

Laser Diode

+24VD

Motors, Clutches, Lamps, Marker, Power Pack

The laser diode is powered by a special +5V supply, called +5VLD. There are two +24V power supplies:

• +24VS: This is always on when the main switch is o n.

• +24VD: This is interrupte d if th e fro nt cover interlock switch opens.

There is no +24VD activation signa l from th e cpu to the PS U.

Printer

Sensors

RS-232C

Interface

1-15

November 30th, 1991 OVERALL MACHINE INFORMATION

POWER DISTRIBUTION

1.6.2. Memory Back-up Circuit

Reference:

Group 3 Facsimile Manual, section 1-4-3, Circuit type 1

+5V

Voltage

Detector

+24V

[A]

+5V

Switching

Circuit

Regulator

MBU

RAM

1-11

1-9

Battery

Switch

Battery

Switching

Circuit

FCU

17-11

17-9

Real Time

Clock

CPU

Memory Monitor

SAF

Memory

Battery

Switch

[B]

Battery

The battery [A] on the MBU backs up the RA M on the MBU, which con ta ins system parameters. It also backs up the rea l time clock in t he cpu . This battery is not rechargeable. CN1-9 te lls the cpu whe th er back-up power (CN1-

11) comes from the battery or the +5V power supply. A rechargeable battery [B ] on the FCU board backs up the SAF memo ry and

the real time clock for 1 hour. While the main power is on, the +24V supply recharges the battery.

If there is data in the SAF memory, the rechargeable ba tt ery [B ] also backs up the real time clock, to preserve the MBU battery.

1-16

[A]

DETAILED SECTION DESCRIPTIONS November 30th, 1991 SCANNER

2. DETAILED SECTION DESCRIPTIONS

2.1. SCANNER

2.1.1. Mechanisms

1. Document Detection

Document Table

Reference:

Group 3 Facsimile Manual, section 2-1-1.

• The scanner is B4-width [1 0. 1" ], with a B4 document width de te ctor [A].

The scanner can feed paper up to 304 mm [1 2"] wide. However, only

10.1" of this width will be scanned. The ext ra width allows users to feed wide originals with wide margins, such as computer form printouts.

• The scanner contains a xenon lamp.

• There is a fold-down extension [B] to support long documents.

[B]

2-1

[A]

Reference:

Group 3 Facsimile Manual, section 2-1-1.

November 30th, 1991 DETAILED SECTION DESCRIPTIONS

SCANNER

Shutter

[C]

[B]

In standby mode, tab [A] rests on cam [B] . Whe n the tx mot or starts, the motor rotates forwards (white arrows), the cam lifts the tab, and the shut ter [C] rises. After the last pa ge ha s be en fed through the scanner, the tx motor reverses (black arrows), the cam drops back to the standb y posit ion, and the shutter blocks the scan ne r p at h again.

2. Pick-up and Feed

Drive Mechanism

Reference:

Group 3 Facsimile Manual, section 2-2-1.

[A]

[B]

[C]

This machine has a Mechanical Clu tch Mecha nism. The tx motor [A] drives the feed roller [B] and pick-up roller [C].

Resolution

Standard - The tx motor feeds the document at 7.7 lines/mm. The video processor executes

OR processing to convert the data into 3.85 lines/mm. Detail - The tx motor feeds the document at 7.7 lines/mm. There is no OR processing, and the data is transmitted at 7.7 lines/mm. Fine - The tx motor feeds the document and transmits data at 15.4 lines/mm. If the other terminal cannot receive at this resolution, alternate lines of data are deleted, so the effective resolution of the transmitted data is 7.7 lines/mm.

2-2

DETAILED SECTION DESCRIPTIONS November 30th, 1991 SCANNER

Jam Conditions

The cpu detects a document jam if one of the following cond itions occurs.

• The scan line sensor does no t switch on with in 9 s of the Start key be-

ing pressed.

• The scan line sensor does no t tu rn off after the maximum document

length has been fe d since it turned on.

• The scan line sensor switch es on wh ile th e do cument sensor is off.

• The document width sensor switches on while the document sen sor is

off.

• The scan line sensor does no t tu rn on wit hin 5 s of the end of sta mpin g,

if the document senso r is on.

Separation

Reference: Group 3 Facsimile Manual, section 2-2-2.

3. Manual Feed

The manual feed butt on [A] lif ts th e separation roller [B] out of the document feed path. There is no manual fe ed switch.

Reference: Group 3 Facsimile Manual, section 2-2-3.

[B]

[A]

2-3

November 30th, 1991 DETAILED SECTION DESCRIPTIONS

SCANNER

2.1.2. Video Data Proces si ng

Output from the CCD

Auto Shading

Memory

WHITE

WAVEFORM

FEEDBACK

Reference:

Group 3 Facsimile Manual, section 2-3

Filter

VIDEO

PROCESSOR

Corrected Data from the Auto Shading Circuit

Amplifier

Gamma

Correction,

MTF

A/D

Converter

Data Processing

Circuits

Halftone

Process

Edge

Detection

To the CPU

and Modem

Basic

EDGE

ELEMENTS

Peak Hold

CORRECTED

DATA

Error Diffusion Halftone

Process

Comparator

Background

Detection

Processing

Reduction

NON-EDGE

ELEMENTS

Reduction

Halftone

Process Selector

To CPU and Modem

2-4

Image/Text

Detection

B’

DETAILED SECTION DESCRIPTIONS November 30th, 1991 PRINTER

2.2. PRINTER

2.2.1. Mechanisms

1. Master Unit

This printer uses a "write to black" syste m, usin g ne ga tive ton er. The master unit contains a durable OPC master belt. The expe cte d lif et ime o f

each master unit is about 60 ,000 copies (this is the target value). Because of this long lifetime, the user is not exp ect ed to cha nge th e mast er; the re is no Replace Master indicator.

The master belt does not have a bond seam, so no mast er ho me position detection is needed. There is also no ma ste r unit in terlock switch; there is an interlock switch on the front cover.

[A]

[B]

The main motor [A] drives the master belt [B].

• At the start of printing , it turns on briefly and the master belt moves un -

der the quenching lamp to ensure that it is fully discharged.

• Then, when the fu sing la mp is at th e correct temperature and the page

memory contains a complete page of da ta, and the hexagonal mirror motor is running at the correct speed , the main mo tor swit che s on again.

• When the main motor is runn ing at th e correct speed, the laser diode

turns on for automatic power control.

Reference: Group 3 Facsimile Manual, section 4-1

2-5

November 30th, 1991 DETAILED SECTION DESCRIPTIONS

PRINTER

2. Charge Corona Unit

[A]

[C]

[B]

[D]

[E]

The charge corona un it [A ] gives a -750 V charge to the ma ster belt. The varistor [B] ensures th at the charge does not exceed this valu e.

The connection between the powe r p ack [C] and the coron a unit is n ot broken when the front cover is o pene d. Ho weve r, the front cover interlock swit ch cuts the +24V power line to the power pack if the cover is o pene d.

The charge corona un it con tains a wire cleaner [D]. The charge corona switch es on at th e same time as the laser diode starts its

power control procedure. There is one ozone fan on the right hand side of the machine. It sucks air out

of the machine thro ugh the ozone filter, which is part of the ozone fan assembly. The ozone fan switches on when a ringing signal is detecte d, an d st ays on until the fusing lamp te mperature falls back below 130 °C at the end of the printing run.

The inset shows how the grid plate [E] connects to the varistor.

Reference: Group 3 Facsimile Manual, section 4-2

2-6

DETAILED SECTION DESCRIPTIONS November 30th, 1991 PRINTER

3. Laser Optics

[E]

[F]

[B]

[D]

[A]

[C]

The optics are the same as those illu stra ted in section 4-3-3 of the Group 3 Facsimile Manual, except that th ere are two mirrors [A] at the "Second Mirro r" position.

Other points to note are as follows:

• The focusing lens [B] is a barrel toroidal lens.

• The shield glass [C] preven ts toner from entering the laser optics are a,

and may need cleaning occasionally.

• An optical fibre [D] passes the ref lected laser beam to the main scan

start detector [E]. This detector is situat ed on the laser d iod e drive b oa rd [F], unlike shown in the diagram.

• The strength of th e beam is 0 .4 36 mW at a wavelength of 780 nm.

• The dimensions of the dot on th e mast er be lt are 65 µm (main scan di-

rection) by 75 µm (sub-scan direction).

The charge on the exposed parts of the belt drop s to abou t -15 0 V, while nonexposed areas remain at abou t -750 V.

The laser engine characte ristics are as follows (refer to page 4-3-21 of the Group 3 Facsimile manual for backg rou nd ).

• Motor speed: 9,240 rpm

• Motor type: Hexagonal

• LD clock frequency: 5.3311 MHz

• Time betwee n main scan synchronization signa ls: 1. 08 2 ms

• Number of dots pe r ma in scan: 5769

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November 30th, 1991 DETAILED SECTION DESCRIPTIONS

PRINTER

4. Development

Overview

This machine uses a ’write-to-b lack’ development system using negative toner.

The toner cassette is part of a dispo sable unit known as the CTM (Cleaning/Toner Magazine). The CTM contains a toner cassette, toner supply mechanism, cleaning unit , an d used to ner t ank. When the toner is all used up, the CTM is replaced.

Reference: Group 3 facsimile Manual, section 4-4

Toner Supply

[B]

[C]

[D]

[E]

When a new CTM is installed in the machine and the front cover is closed, the main motor and to ne r su pp ly mo to r t urn on. When the front cover is closed, a tab [A] o n the fusing unit cover forces the hopper [B] t o ope n. Also, tab [C] on the CTM pushes bracket [D], which mo ves th e CTM sensor actuator into the sensor.

Continued on the next page

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DETAILED SECTION DESCRIPTIONS November 30th, 1991 PRINTER

[F]

[H]

[I] [J]

The toner supply motor [F] drive s the ton er sup ply sha ft ([E] in the diagram on the previous page). This spiral shaft feeds toner to the ho pper.

Inside the development unit is another spiral shaft [G]. This shaft, d riven by the main motor, distributes toner across the length of trough [H]. The toner supply motor drives gear [I], and once every rot at ion , it tips the trough upside down, dropping t he toner into the develo pment unit. A sprin g immediately pulls the trough back upright so that it can cont inu e to receive ton er.

[G]

[K]

The toner mixing bar [J], driven by the main motor, keeps the toner agitated as it builds up at the botto m of th e de velopment unit. The toner supply bar [K] supplies toner to the de velo pment roller.

While toner is being supplied, th e main motor is also operating the toner nearend detection mecha nism. When a fresh toner cassett e is installed, the sensor detects toner near-end, because there is not much ton e r in th e development unit. Wh en some to ne r has be en transferred, the signal from the toner near-end senso r ret urns to normal. About 22 s aft er t ha t, th e ton er supply motor stops and no more toner is transferred into the development unit.

During printing, if toner near-en d is detect ed , the tone r supply mechanism will start up again. Toner will be supplied until t he sensor signal returns to normal. If the toner cassette in the CTM is empty, no toner will be transferred, and th e sensor signal will not return to normal. If the sen sor ou tp ut s the nea r-en d signal for more than 5 minu te s, t he cpu blinks the Add Ton er indicator. See "Toner Near-end Detection" for more details.

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November 30th, 1991 DETAILED SECTION DESCRIPTIONS

PRINTER

Development Unit Drive

[A]

[B]

During printing, drive from th e main moto r at gear [A] drives the development roller [B]. The main moto r a lso drive s the master belt, so the developme nt roller and the master belt always move at the same time; there fo re, no development clutch is needed.

Toner Near-end Detection

The toner near-end de te ction mechanism is exactly the same as described in section 4-4-4 of the Grou p 3 Facsimile Manu al. The sensor signal is as shown in the following diagram.

Reference:

Group 3 Facsimile Manual, section 4-4-4.

1.9 s

0.1 ms

The cpu starts to blink the Add Toner indicator under the follo wing conditions:

• At power up: If the sensor ou tp ut indicates toner near-e nd for 6 s

• During printing: If the senso r o ut pu t ind icates toner near-end fo r more

than 5 minutes, totalled over consecutive print runs (when the motor stops, the sensor mechanism is deactivated, so time between printing runs does not count towards the 5 minute time limit)

After 100 more pages ha ve b een p rint ed , t he Ad d Toner indicator remains lit, and printing is disabled until a new CTM has bee n added.

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DETAILED SECTION DESCRIPTIONS November 30th, 1991 PRINTER

Development Bias

[B]

[A]

The development bias and switch ing bias are supp lied from th e po wer pa ck [A] at the same terminal [B].

• Development bias: - 530 ± 20 Vdc (BIASL)

• Switching bias: +70 ± 20 Vdc (BIASH)

The switching bias is used at the following times:

• Between pages of a prin t run , while the development bia s is off

• While toner is being transfe rred from the CTM to the development unit

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November 30th, 1991 DETAILED SECTION DESCRIPTIONS

PRINTER

5. Paper Feed

There are two cassette s, a 25 0-sh ee t cassette, and an optional 500-sheet cassette.

The sizes of paper that the cassettes can take are listed in the specifications (section 1-1).

[A]

Paper feeds from the rear towards the front . The lower paper feed path bends upward through the front part of the upper cassette. The two paper feed paths merge just before the registratio n rolle r [A] .

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