Ricoh FW810 Service Manual

SECTION 1

OVERALL MACHINE INFORMATION

6 January 1990

1. SPECIFICATIONS

Configuration: Table top Copy Process: Electrostatic transfer system Original Feed: Sheet feed Original Size: Maximum: 914 x 3,600 mm

Minimum: 182 x 257 mm (B5 lengthwise) Copy Size: Same as "Original Size" Copying Speed: Manual feed: 5 cpm (A1/D sideways)

Tray feed: 6 cpm (A1/D sideways) First Copy: 22 seconds (A1 sideways) Warm-up Time: Within 7 minutes (Room temperature 20 Copy Counter: 1 to 9

Automatic Reset: 2 minutes after copying is finished (can be set

to 1, 3, 4, or 5 minutes or to no auto reset) Photoconductor: Organic photoconductor drum Drum Charge: Single-wire with grid plate (Negative Charge) Reproduction Ratio: 1 : 1 (

±0.5%)

Exposure System: Slit exposure via fiber optic array Exposure Lamp: Fluorescent lamp (65 W) Development: Dual-component dry toner system Toner Replenishment: Cartridge system (750 g toner/cartridge) Toner Consumption: 1,600 A1 or D copies per cartridge (7% original) Development Bias: Negative Toner Density Control: Pattern density detection by photosensor and

direct toner density detection by induction

sensor Image Density Adjustment: Development bias control + exposure control +

grid voltage control Auto Image Density

Development bias control and exposure control Control:

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6 January 1990

Image Transfer: Single wire dc corona (negative charge) with

pre-transfer lamp Paper Separation: Dual wire ac corona and pick-off pawls Cleaning: Cleaning blade Quenching: Photo quenching by LEDs Paper Feeding: Manual feed (auto sheet feeder optional) Image Fusing: Heat and pressure type, teflon (upper) and

silicone rubber (lower) rollers Fusing Lamp: Halogen lamp (115 V: 1,100 W, 220/240 V:

1,100 W) Self-diagnostic Codes: 14 codes, displayed in copy counter

Power Source: 115 V/60 Hz....12 A

220 V/50 Hz....7 A

240 V/50 Hz....7 A

Power Consumption: Maximum: 1.4 kW

Warm-up: 1.2 kW

Ready: 0.1 to 1.2 kW

Copy cycle: 1.4 kW Ozone Output: Less than 0.1 ppm (1000 ft

at least 3 times per hour) Dimensions (W x D x H): 1,410 x 800 x 600 mm

55.51 x 31.50 x 23.62 in Weight: 180 kg, 397 lb Optional Equipment: ---- Automatic sheet feeder

---- Roll cutter

---- Paper spool

room, air turnover

1-2

2. OPERATOR CONTROLS

2.1 OPERATION PANEL

6 January 1990

15 16

1. Manual Image Density Indicators

Show the image density level selected by the Lighter and Darker keys.

2. Lighter Copy Indicator

There are 14 manual ID levels but only 7 manual ID LEDs. The Lighter Copy indicator lights when manual ID levels from 8 to 14 are selected.

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6 January 1990

3. Wait Indicator

Indicates that the machine is not ready to copy.

4. Select Paper Key

Press to select manual feed or the auto sheet feeder.

5. Ready Indicator

Lights when the machine is ready to make copies.

6. Auto Sheet Feed Indicator

Lights when the auto sheet feeder is selected.

7. Manual Feed Indicator

Lights when the manual paper feed mode is selected.

8. Add Paper Indicator

Lights when the auto sheet feeder runs out of paper.

9. Add Toner Indicator

Lights when it is time to install a new toner cartridge.

10. Original Misfeed Indicator

Lights if an original misfeeds within the copier.

11. Misfeed Indicator

Lights if paper misfeeds within the copier.

12. Close Unit Indicator

Indicates that one of the copier’s units is open. The copier will not operate until it is completely closed.

13. Toner Collection Bottle Indicator

Lights when it is time to empty the toner collection bottle.

15. Copy Counter

Displays the number of copies entered, the number of copies made, and service codes.

16. Copy Exit Way Key

Selects either upper or lower copy exit.

17. Lead Edge Erase Indicators

Shows the width of the leading edge erase margin.

18. Lead Edge Erase Key

Selects the amount of leading edge erase.

19. Clear Modes Key

Press to clear the copier of previously entered settings.

20. Clear/Stop Key

Press to cancel the copy number entered. While copying, press to stop copy operation.

21. Plus Key

Press to increase the number of copies to be made. (The maximum repeat copies is 9.)

22. Minus Key

Press to decrease the number of copies to be made.

23. Auto Image Density Indicator

Lights when the copier is automatically controlling the image density.

24. Auto Image Density Key

Press to enter and exit the auto image density mode.

25. Darker Key

Press to make copies darker

14. Call Service Indicator

Indicates that there are functional problems within the copier.

26. Lighter Key

Press to make copies lighter.

1-4

2.2 INDICATOR PANEL

6 January 1990

1. Insert Original Indicator

Lights when the machine is ready for an original to be inserted. Turns off when an original is inserted.

2. Stop Key

Press to stop the copier during a copy cycle (emergency stop).

3. Insert Copy Paper Indicator

Lights when the machine is ready for a sheet of copy paper to be inserted. Turns off when a sheet of copy paper is inserted.

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6 January 1990

3. DRUM PROCESSES

1. Charge

In the dark the charge corona unit applies a negative charge to the drum. The grid plate ensures the charge is applied uniformly. The charge remains on the surface of the drum because the photoconductive drum has a high electrical resistance in the dark.

2. Exposure

High intensity light from a fluorescent lamp is reflected from the moving original through the fiber optic array. The charge on the drum surface is dissipated in direct proportion to the intensity of the reflected light, thus producing an electric latent image on the drum surface.

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6 January 1990

3. Development

The magnetic developer brush on the development roller comes in contact with the latent image on the drum surface. Toner particles are electrostatically attracted to the negatively charged latent image areas.

4. Pre-Transfer Lamp

The pre-transfer lamp illuminates the drum prior to image transfer. This reduces the attraction between the toner and the drum, thus making image transfer easier.

5. Image Transfer

Copy paper is fed to the drum surface at the proper time to align the copy paper and the developed image on the drum surface. Then a strong negative charge is applied to the back side of the paper. The negative charge pulls the toner particles from the drum surface onto the paper.

6. Paper Separation

A strong ac corona discharge is applied to the back side of the copy paper, reducing the charge on the paper and breaking the electrostatic attraction between the paper and the drum. Then, the stiffness of the copy paper causes it to separate from the drum. The pick-off pawls help to separate paper which has low stiffness.

7. Cleaning

The cleaning blade removes any toner remaining on the drum surface.

8. Quenching

The light from the quenching lamp electrically neutralizes the surface of the drum.

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6 January 1990

4. MECHANICAL COMPONENT LAYOUT

2 1

24 25

3940

1. 1st Feed Detector

2. 2nd Feed Detector

3. Toner Cartridge

4. 5th Press Roller

5. Original Recycle Gate

6. Original Set Detector

7. Front Original Feed Roller

8. 1st Press Rollers

9. Original Exit Detector

10. 1st Original Transport Detector

11. Exposure Lamp

12. Platen Roller

13. Fiber Optic Array

14. Charge Corona Unit

15. 2nd Original Transport Detector

16. Original Registration Rollers

17. 4th Press Rollers

18. 2nd Press Rollers

19. Rear Original Feed Roller

20. 3rd Press Rollers

21. Quenching Lamp

22. Upper Exit Rollers

23. Upper Exit Sensor

24. Exit Rollers

25. Exit Gate

26. Exit Detector

27. Lower Exit Sensor

28. Hot Roller

29. Pressure Roller

30. Transport Belt

31. Transport Sensor

32. Cleaning Unit

33. Pick-off Pawls

34. OPC Drum

35. T/S Corona Unit

36. Paper Registration Rollers

37. Pre-Transfer Lamp

38. Registration Sensor

39. Development Unit

40. Manual Feed Rollers

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5. DRIVE LAYOUT

6 January 1990

26 25

1. Original Drive Belt 2

2. Rear Original Feed Rollers

3. Original Drive Clutch

4. Main Drive Motor

5. Original Registration Rollers

6. Original Drive Belt 3

7. Platen Roller

8. Front Original Feed Rollers

9. Development Roller Gear

10. Auger Gear

11. Toner Supply Clutch

12. Development Motor

13. Paper Feed Clutch

14. Paper Feed Drive Chain

15. Development Drive Belt

16. Paddle Roller Gear

17. Registration Roller Clutch

18. Drum Drive Gear

19. Toner Collection Coil Gear

20. Feed/Fusing Drive Belt 2

1820

21. Fusing Drive Chain

22. Drum Drive Belt

23. Feed/Fusing Drive Belt 1

24. Transport Roller Sprocket

25. Hot Roller Sprocket

26. Lower Exit Roller Sprocket

27. Exit Roller Drive Chain

28. Upper Exit Roller Sprocket

29. Original Drive Belt 1

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6 January 1990

6. ELECTRICAL COMPONENT LAYOUT

6.1 MIDDLE AND UPPER SECTIONS

40 39

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6.2 LOWER AND FUSING SECTIONS

6 January 1990

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6 January 1990

1. Development Motor

2. Development Motor Capacitor

3. Charge/Bias PP

4. Lamp Regulator

5. Main Motor Capacitor

6. Light Sensor

7. Cooling Fan

8. Original Feed Clutch

9. Main Motor

10. Indicator Panel

11. 1st Original Transport Detector

12. Original Registration Sensor

13. 2nd Original Transport Detector

14. Auto Density Sensor

15. Upper Exit Sensor

16. Exit Sensor

17. Lower Exit Sensor

18. Pattern Shutter SOL

19. Upper Safety Switch

20. Rear Safety Switch

21. Exit Gate SOL

22. Pulse Generator

23. Exhaust Fan

24. Toner Overflow Sensor

25. Recycle Gate SOL

26. Main Board

27. Exposure Lamp

28. Recycle Gate Detector

29. Operation Panel

30. Pre-Transfer Lamp

31. ID Sensor

32. Pick-off Pawl SOL

33. Registration Sensor

34. 2nd Feed Detector

35. 1st Feed Detector

36. Toner Density Sensor

37. Paper Stopper SOL

38. Original Exit Detector

39. Original Set Detector

40. Original Stopper SOL

41. Quenching Lamp

42. Toner Cover SW

43. Toner Supply SOL

44. Manual Feed SOL

45. Registration SOL

46. Fusing Lamp

47. Transfer/Separation PP

48. DC Power Supply

49. Hot Roller Thermistor

50. AC Controller 2

51. AC Controller 1

52. Fusing Thermofuse (x2)

53. Pressure Roller Thermistor

54. Triac

55. Vacuum Fan

56. Circuit Breaker

57. Noise Filter

58. AC Terminal Block

59. Auto Feeder Safety Switch

60. Main Switch

61. Total Counter

62. Lower Safety Switch

63. Vacuum Fan Motor Capacitor

64. Transport Sensor

65. Anticondensation Heater

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6 January 1990

7. ELECTRICAL COMPONENT DESCRIPTIONS

SYMBOL NAME FUNCTION LOCATION

Motors

M1 Main Motor Drives all mechanical components

except the development unit and the fans. (100 Vac)

M2 Development

Motor

M3 Exhaust Fan

Motor

M4 Cooling Fan Mo-

tor

M5 Vacuum Fan Provides suction so that paper is held

Magnetic Clutches

MC1 Original Feed

Clutch

MC2 Registration

Clutch

Solenoids

Drives the development unit. (100 Vac) 1

Removes heat from around the fusing unit. (100 Vac)

Provides air flow to the optics cavity. (100 Vac)

firmly on the transport belts and rollers. (100 Vac)

Drives the original feed mechanism. 8

Drives the registration rollers. 45

SOL1 Toner Supply

Solenoid

SOL2 Pattern Shutter

Solenoid

SOL3 Exit Gate Sole-

noid

SOL4 Pick-off Pawl

Solenoid

SOL6 Paper Stopper

Solenoid

SOL7 Manual Feed

Solenoid

SOL8 Recycle Gate

Solenoid

Turns on to supply toner to the development unit.

On ID check cycles, this solenoid turns on to move the pattern plate into the light path.

Controls the position of the exit gate. (When ON, the paper exits downward; when OFF, the paper exits upward.)

Moves the pick-off pawls against the drum.

Moves the paper stopper down to prevent paper from being inserted.

Turns ON to engage the manual feed clutch.

Controls the position of the recycle gate. (ON = recycle gate in down position, OFF = recycle gate in up position.)

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6 January 1990

SYMBOL NAME FUNCTION LOCATION

SOL9 Original Stopper

Solenoid

SOL10 Auto Feeder So-

lenoid 1

SOL11 Auto Feeder So-

lenoid 2

Moves the original stopper down to prevent an original from being inserted.

Turns the paper feed roller of the auto sheet feeder. turns the relay rollers of the auto sheet feeder.

----

Switches

SW1 Main Switch Supplies power to the copier. 60 SW2 Upper Safety

Switch

SW3 Lower Safety

Switch

SW4 Rear Safety

Switch

SW5 Toner Cover

Switch

Cuts ac 100 volt power when the upper unit is opened.

Cuts ac 100 volt power when the middle unit is opened.

Cuts ac 100 volt power when the paper exit unit is opened.

Cuts power to the toner supply solenoid and the main motor when the

toner cartridge cover is opened.

SW6 Auto Feeder

Safety Switch

Prevents main motor operation when the auto feeder is not set.

Sensors and Detectors

S1 Image Density

Sensor

S2 Toner Density

Sensor

S3 Toner Overflow

Sensor

S4 Pulse Generator Supplies timing pulses to the main

Detects the image density of the test pattern on the drum.

Detects the density of toner in the developer.

Detects when the used toner tank is full.

board (photointerrupter).

S5 Original Set De-

Detects when an original is inserted. 39

tector

S6 1st Original

Monitors movement of the original. 11 Transport Detector

S7 2nd Original

Monitors movement of the original. 13 Transport Detector

S8 Original Regis-

tration Sensor

SYMBOL NAME FUNCTION LOCATION

Detects when the original lead edge

passes the original registration rollers.

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6 January 1990

Original Exit De-

Monitors movement of the original. 38 tector

S10 Recycle Gate

Detector

S11 1st Feed

Detects whether the recycle gate is in

the up or down position.

Detects when copy paper is inserted. 35 Detector

S12 2nd Feed

Detector

Monitors copy paper movement

between the manual feed rollers and

the registration rollers.

S13 Registration

Sensor

S14 Transport

Sensor

Detects when copy paper arrives at

the registration rollers.

Monitors paper movement between

the transfer/separation section and the

fusing unit.

S15 Exit Detector Monitors copy paper movement

through the exit unit.

S16 Upper Exit

Sensor

S17 Lower Exit

Sensor

S18 Auto Sheet

Feeder Sensor

Monitors copy paper movement

through the upper exit guides.

Monitors copy paper movement

through the lower exit guides.

Detects misfeeds in the auto sheet

feeder.

33 64

----

S19 Paper End De-

tector

Detects when the auto sheet feeder

runs out of paper.

Printed Circuit Boards

PCB1 Main Board Controls all copier functions both

directly and through other PCBs.

PCB2 DC Power

Supply

Provides dc power for all components

of the machine.

PCB3 AC Controller 1 Provides ac power to the fusing lamp

and triac.

PCB4 Lamp Regulator Provides power to the exposure lamp. 4 PCB5 AC Controller 2 Provides ac power to the main motor

and development motor.

PCB6 Indicator Panel Contains the paper and original

insertion indicators and the original

feed stop key.

PCB7 Operation Panel Contains the operator controls and

indicators.

----

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6 January 1990

SYMBOL NAME FUNCTION LOCATION

Lamps

L1 Exposure Lamp Provides light to reflect the original’s

image onto the drum.

L2 Quenching

Lamp

Neutralizes any charge remaining on

the drum surface after cleaning.

L3 Fusing Lamp Provides heat to the fusing unit. 46 L4 Pre-Transfer

Lamp (PTL)

Reduces the charge on the drum

surface prior to image transfer.

Power Packs

P1 Charge/Bias

Power Pack

Provides high voltage power for the

charge corona, charge grid, and

development bias.

P2 Transfer/Sepa-

ration Power Pack

Provides high voltage power for the

transfer corona and separation

coronas.

Thermistors

TH1 Hot Roller

Thermistor

TH2 Pressure Roller

Thermistor

Monitors the hot roller’s surface

temperature.

Monitors the pressure roller’s surface

temperature.

TH3 Exposure Lamp

Thermistor

Monitors the fluorescent lamp’s

temperature.

----

Thermofuses

TF1 Fusing

Thermofuse

TF2 Exposure Lamp

Thermofuse

Protects against fusing overheat. (Two

thermofuses in parallel.)

Protects against exposure lamp

overheat.

Heaters

H1 Lamp Heater Warms the scanning lamp. ---H2 Anticondensa-

tion Heater

Keeps moisture from forming inside

the copier.

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6 January 1990

SYMBOL NAME FUNCTION LOCATION

Others

CO1 Total Counter Keeps track of the total length of

copies made.

NF Noise Filter Filters electrical noise on the ac power

input lines.

TR Transformer Steps down the line voltage to 100

----

Vac.

TR Triac Provides ac power to the fusing lamp. 54

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6 January 1990

8. AC POWER DISTRIBUTION

Interlock Switches

SW3 SW4 SW2

Hot

C.B

Main Switch

(SW1)

Neutral

T304

N. F

T306

T307 T305

Controller 1

(PCB3)

Thermofuse(x2)

T309 T1 T310 G

T308

Fusing Lamp(L3)

CN3

-4

-5

Triac

Lamp

Regulator

(PCB4)

Exposure Lamp(L1)

Trans-

fomer

Anticondensation Heater

Exhaust

Fan

Cooling

Fan

CN1

-1 M4

-2

CN3

-1

-2 Vacuum

Fan

Main

Motor

Develop-

ment

Motor

CN402

-1

-2

CN404

-1

-2

AC Controller 2(PCB5)

1-18

CN401-1

CN401-2

6 January 1990

The preceding schematic shows how ac power is distributed in this machine. The ac power from the wall outlet passes through the noise filter, circuit breaker, and three interlock switches to the transformer and to ac controller

1. AC controller 1 powers the fusing lamp with direct wall outlet ac power. The main board controls the fusing lamp through the triac. The transformer steps the ac power down to 100 volts and then provides it to

the main switch. If the main switch is off, power is applied only to the anticondensation heater. If it is on, at 100 volts goes to the fan motors, ac controller 2, and the lamp regulator.

AC controller 2 provides ac 100 volts power to the main motor and development motor. RA401/402 turn the motors on and off.

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6 January 1990

9. DC POWER SUPPLY

FU1

CN1-1

AC LINE

ZNR

CN2-1

I C H

I N G

Vcc

C. GND

CN2-2

DC5V

C O N T

CN1-3

AC NEUTRAL

R O

Vaa

FU2

Above is a simplified schematic of the dc power supply. The dc power supply provides +5 volts (Vc) and +24 volts (Va) from CN2-2

and CN2-7 respectively to the main board. Also +24 volts (Va) is provided to the charge/bias power pack from CN2-6 and to the transfer/separation power pack from CN2-8.

CN2-3,4,5

A. GND

CN2-6,7,8

DC24V

1-20

SECTION 2

DETAILED SECTION DESCRIPTIONS

6 January 1990

1. DRUM

1.1 DRUM CHARACTERISTICS

The organic photoconductor (OPC) drum has the following characteristics:

• It is able to accept a high negative electrical charge in the dark. (The elec-

trical resistance of the OPC drum is high in the absence of light.)

• The electric charge on the drum surface dissipates when the drum is ex-

posed to light. (The conductivity of the OPC drum is greatly enhanced by exposure to light.)

• Dissipating an amount of charge in direct proportion to the intensity of the

light. That is, where stronger light is directed to the photoconductor surface, a smaller voltage remains on the selenium.

The OPC drum used in this model has high sensitivity, good color reproduction, and good reproduction of low contrast originals (pencil originals, etc.)

1.2 HANDLING THE DRUM

The organic photoconductor drum is very sensitive to light, temperature, and corrosive gases. Please observe the following cautions when handling the OPC drum.

1. Never expose the drum to sunlight.

2. Never expose the drum to light of more than 1000 Lux for more than a minute.

3. Never touch the drum surface with bare hands. When the drum surface is touched with bare hands or becomes dirty, wipe with a dry cloth or clean with wet cotton. Wipe with a dry cloth after cleaning with wet cotton.

4. Never use alcohol when cleaning the drum. (Alcohol tends to dissolve the OPC layer.)

5. Store the drum in a cool, dry place away from heat.

6. Take care not to scratch the drum as the OPC layer is thin and easily damaged.

7. Never expose the drum to corrosive gases such as ammonia gas.

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6 January 1990

1.3 DRUM DRIVE

[F]

[B]

[E]

[D]

[C]

[G]

[J]

[H]

[I]

[A]

The OPC drum [A] is 80 millimeters in diameter and 970 millimeters long. It turns constantly when the main motor [B] is on.

When the main motor turns on, drive is transmitted to the drum as follows: main motor drive gear [C] ⇒ idle gear [D] ⇒ main drive pulley gear [E] ⇒ drum

drive belt [F] ⇒ drum drive gear [G] ⇒ drum flange [H] ⇒ drum When the drum knob [I] is tightened, the right flange [J] presses firmly against

the drum so that the drum is held tightly between the flanges. The drum and flanges turn together when the main motor is on.

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2. CHARGE

2.1 OVERVIEW

6 January 1990

[A]

[B]

Charge

Grid

This model uses a single wire corona unit [A] to charge the OPC (organic photoconductor) drum [B]. The corona wire generates a corona of negative ions when a high negative voltage is applied to it by the charge/grid power pack [P1].

To make the negative corona uniform, a grid consisting of 8 wires is installed on the charge corona unit between the corona wire and the drum. This grid drains off any charge in excess of --940 volts, thus preventing fluctuation of the charge potential.

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6 January 1990

2.2 CHARGE CORONA CIRCUIT

Charge / Bias PP

DC/DC

Converter

DC/DC

Converter

CN1-1

CN1-2

CN1-3

CN1-6

CN1-10

CN2

-6

CN107

-B14

CN110

-1

-8

DC Power

24V Va

GND

Main Board

Charge

Grid Drive

0/5

Grid monitor

2.5

The main power supply board supplies +24 volts (Va) to the charge/bias power pack as the power supply source. About 8 seconds after the Start key is pressed, the CPU drops CN107-B14 from +24 volts to 0 volt. This actuates the dc/dc converter within the power pack which applies a high negative voltage of approximately --5.3 kV to the charge corona wire. The corona wire then generates a negative corona charge.

The grid limits the maximum corona charge to --940 volts. This ensures that the charge does not fluctuate and an even charge is applied to the drum surface. When developing the test pattern for the image density sensor, the grid charge is --460 volts.

The copy grid voltage, and ID sensor grid voltage amounts can be adjusted using service program modes #23 and #22, respectively.

The grid drive signal applied to CN1-6 is a pulse width modulated signal. As the width of the pulses applied increases, the strength of the grid charge also increases. The main board monitors the grid charge at CN110-8 and controls the width of the drive pulses based on this feedback.

2-4

3. EXPOSURE

3.1 OVERVIEW

[A]

6 January 1990

[D]

[F]

[E]

[B]

Light from the exposure lamp [A] reflects off the original and through the fiber optics [B] to the OPC drum [C]. During exposure, the original moves across the exposure glass at the same speed as the drum’s peripheral velocity.

The platen roller [D] presses the original [E] flat against the exposure glass [F] just above the fiber optic array. This ensures that the image is properly focused. (The original must be within 0.2 mm of the exposure glass surface.)

The exposure lamp is a 100 V, 65 W fluorescent lamp. This lamp has a heater which prevents a reduction in light output due to low temperatures. The heater maintains the lamp’s temperature at 40oC

[C]

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6 January 1990

3.2 ORIGINAL FEED

3.2.1 Basic Operation

[G]

[F]

[I]

[B]

[A]

[C]

[H]

[L]

[J]

[K]

[E]

When the original is inserted on the original table [A], it activates the original set detector [B]. The main motor then turns on. Two seconds later the original feed clutch turns on to start turning the front original feed rollers [C], rear original feed rollers [D], and original registration rollers [E]. The two second delay allows time for the operator to align the lead edge of the original against the first set of rollers to prevent skew.

[D]

The original is fed past the 1st and 2nd original transport detectors [F,G] and around the rear original feed rollers to the original registration rollers. The original feed clutch turns off 0.2 second after the original’s leading edge activates the original registration sensor [H]. The original remains at this position until a sheet of copy paper is fed.

Just before the copy paper reaches the registration sensor, the original feed clutch turns on again and original feed resumes. The original passes between the platen roller [I] and the exposure glass [J] and from there to the front original feed rollers. The original’s image density is measured by the ADS at this time. The original’s image is reflected through the fiber optic array to the drum as it passes between the platen roller and the exposure glass.

If making a single copy, the original then exits the machine. However, if making repeat copies, the recycle gate [L] directs the original around the front original rollers to the upper part of the original transport mechanism. The original transport cycle then repeats.

The maximum original length for repeat copying is 610 millimeters. If the operator attempts repeat copying with an original longer than 610 millimeters, it will automatically feed out after making a single copy.

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3.2.2 Drive Mechanism

[A]

6 January 1990

[B]

[C]

Drive power from the main motor is provided to the original transport mechanism from the original drive pulley through original drive belt 2 [A]. When the original drive clutch [B] is energized, original drive belt 3 [C] starts turning the front original feed rollers and the original registration rollers. The rear original feed rollers are driven directly by the original drive clutch.

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6 January 1990

3.3 ORIGINAL STOPPER MECHANISM

[A]

[B]

Originals should not be inserted during a copy cycle. To prevent originals from being inserted, the machine locks the feeler of the original set detector in the down position while copying. This is accomplished by the original stopper solenoid [A].

When the original stopper solenoid turns on, the stopper arm [B] rotates against the feeler of the original set sensor. This locks the feeler in the down position so that originals can only be inserted as far as the original set sensor.

2-8

3.4 EXPOSURE LAMP CONTROL

[PCB4]

6 January 1990

+5V

PWM

CN1-1

CN1-2

CN2-1

CN2-2

LAMP

REGULATOR

CN3-1

CN3-2

CN3-4 CN3-5

Lamp OFF (+5V)

Lamp ON (GND)

T = 1.0 ms Duty = 15% to 100%

[L1]

Exp. Lamp

The lamp regulator receives 100 volts ac at CN1-1 and CN1-2. It also receives +5 volts, which is used in the lamp regulator’s control circuit, from the main board at CN2-1. The control signal, which is a pulse width modulated (PWM) signal, is received at CN2-2. The PWM signal has a period (T) of 1 millisecond and a duty of 15% to 100%.

The basic light intensity level is determined either by the image density selected from the operation panel (manual ID control) or by the original’s background level as sensed by the ADS. The CPU uses the light sensor to monitor the actual light intensity. The light sensor directly senses the lamp’s light output and feeds a light intensity signal back to the main board. This feedback allows the CPU to compensate for variations in light intensity due to the lamp’s age or temperature.

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6 January 1990

3.5 MANUAL ID CONTROL VS ADS

1.4

Light Sensor Output (Volts)

1.2

1.0

0.8

0.6

1 2

3 4

9 10 11

Manual ID Level

Darker Lighter

3.5.1 Manual ID Control

When in manual image density mode, the user can select one of 14 manual ID levels. For each level, the intensity of the light output by the exposure lamp (as measured by the light sensor) is fixed. This is shown in the above graph. For manual ID levels 2 through 7, the development roller bias also varies. (See the section on development bias.)

2-10

Vod/Vsd VS [V]

0 ∼ 0.18 0.86

0.19 ∼ 0.46 1.74

0.47 ∼ 0.49 1.64

0.50 ∼ 0.53 1.54

0.54 ∼ 0.57 1.45

0.58 ∼ 0.61 1.37

0.62 ∼ 0.65 1.29

0.66 ∼ 0.69 1.21

0.70 ∼ 0.73 1.15

0.74 ∼ 0.77 1.05

0.78 ∼ 0.85 0.94

6 January 1990

0.86 ∼ 0.86

VS: Light Sensor Voltage VOD: Original Density Detecting Voltage VSD: Standard Pattern (White Plate) Density Detecting Voltage

3.5.2 ADS Control

When automatic image density sensing (ADS) is used, the exposure light intensity varies depending on the background image density of the original. The preceding table shows how the exposure light intensity changes depending on the VOD/VSD ratio.

Use service program mode #10 to select the default ID setting. It can be set to ADS or Manual ID level 4. The factory setting is ADS.

NOTE: If the exposure lamp cannot output sufficient light, service call

condition "E1" exists. However, copying is still possible. Refer to the "SERVICE CALL CONDITIONS" table.

2-11

6 January 1990

3.6 AUTO DENSITY SENSOR (ADS)

[A]

Center Line

10mm

Sampled Area

33.5 mm

18 mm

The ADS [A] measures the reflectivity of the original’s background. Based on the originals background image density, the CPU automatically adjusts the development bias and exposure light intensity to achieve a good copy image.

The ADS is located at the original registration rollers. It reads the white plate (standard white), which is located above the ADS, prior to the arrival of the original. This standard white level (VSD) is used for comparison with the background level of the original (VOD).

The ADS samples a 43.5 mm by 10 mm area near the leading edge of the original. As shown in the above illustration, sampling starts 15 mm from the leading edge.

The highest voltage detected by the ADS is held (peak hold) and used for the exposure voltage adjustment.

2-12

3.6.1 ADS Circuit

6 January 1990

R404

PD-

401

LAMP401

IC401

D401

C404

C403

R403

R401

IC401

CN401-1

C401

R402

C402

CN401-3

CN401-5

CN401-2

CN401-4

CN401-6

CN401-7

Vcc(+5V)

ADS:OUT

ADS ADJUST

C-GND

ADS RESET

Vcc(+5V)

SENSOR LAMP

The ADS circuit is powered by +5 volts, which is provided at CN401-1 for the detection circuit and CN401-6 for the lamp. The CPU resets the ADS by dropping CN401-4 to 0 volt; this discharges C403 to reset the peak hold function. The resistance of PD401 varies with the strength of the light striking it. The two op-amps amplify the effect of the change in PD401 and output the ADS signal at CN401-3.

2-13

6 January 1990

3.7 LAMP HEATER

[A]

[B]

This copier uses a fluorescent lamp [A] as the exposure light source. The output of the exposure lamp varies depending on the temperature; low temperatures especially degrade the light output. To prevent fluctuations in temperature from affecting the copy image, the lamp heater [B] keeps the lamp’s temperature at 40°C.

2-14

3.8 LAMP HEATER CONTROL CIRCUIT

6 January 1990

AC 100 V

PCB1

L. Heater ON

TH3 Short

TH3 Input

TH3 Open

Va2424

00/5

GND

00/5

PCB5

CN107

-A2

-B2

-A1

5Vc

-B3

-A3

-B1

-B4

CN407

-2

-1

CN408

-3

-2

-1

-5

-4

SSR 401

Comparator

Circuit

CN401

-2

-1 CN406-1

CN406-2

CN407-4

TH3

CN407-3

The lamp thermistor, which is mounted together with the lamp heater, monitors the lamp temperature. Based on the input from this thermistor at CN107-B1, the CPU on the main board determines whether or not to turn on the lamp heater. To turn on the lamp heater, the main board drops CN107-B2 to 0 volts. This turns on SSR401 on ac controller 2, which provides ac power to the heater.

If the exposure lamp thermistor short circuits, the comparator circuit drops CN107-B3 to LOW. The copier then stops operation, the Call Service Indicator (wrench mark) lights, and "E" and "8" are alternately displayed in the Copy Counter.

If there exposure lamp thermistor circuit becomes open, the comparator circuit changes CN107-B4 from LOW to a 5 volt pulses. The copier then stops operation, the Call Service Indicator (wrench mark) lights, and "E" and "7" are alternately displayed in the Copy Counter.

2-15

6 January 1990

4. DEVELOPMENT

4.1 OVERVIEW

[C]

[A]

When the main motor turns on, the paddle roller [A] and development roller [B] start turning. The paddle roller picks up developer in its paddles and transports it to the development roller. Internal permanent magnets in the development roller attract the developer to the development roller sleeve.

The turning sleeve of the development roller then carries the developer past the doctor blade [C]. The doctor blade trims the developer to the desired thickness and creates backspill to the cross-mixing mechanism.

[B]

The development roller continues to turn, carrying the developer to the selenium drum. When the developer brush contacts the drum surface, the negatively charged areas of the drum surface attracts and holds the positively charged toner. In this way, the latent image is developed.

Negative bias is applied to the development roller to prevent toner from being attracted to non-image areas on the drum that may have residual positive charge. The bias also controls image density.

After turning about 100 degrees more, the development roller releases the developer into the developer tank. The developer is agitated by the paddle roller and the cross-mixing mechanism.

Also, in this machine, rotation of the paddle roller and development roller tend to cause air pressure inside the unit to become higher than the air pressure around the development unit. Therefore, a hole fitted with a filter, has been added to the top of the unit to relieve air pressure and to minimize toner scattering.

2-16

4.2 DRIVE MECHANISM

6 January 1990

[D]

[C]

[F]

[G]

[H]

[B]

[I]

[E]

[A]

To reduce load on the main motor, the development unit uses a separate drive motor [A]. The development drive pulley turns the development drive belt [B] which turns the development drive gear [C]. The development drive gear turns the development roller gear [D] and the paddle roller gear [E]. The auger gear [F] is engaged with the paddle roller gear. Thus, the development roller, paddle roller, and auger all turn when the development drive motor is on.

The toner agitator gear [H] is also turned by an idle gear [G], which is engaged with the auger gear. However the toner agitator does not turn unless the toner supply clutch [I] is engaged. It engages when the toner supply solenoid turns on.

2-17

6 January 1990

4.3 CROSS MIXING

[C]

[B]

[E]

[F]

[A]

[D]

"Crossmixing" keeps the toner and carrier evenly mixed in the developer and evenly distributes the developer within the development unit. Crossmixing also agitates the developer to generate the necessary triboelectric charge on the toner and carrier particles.

The arrows in the above illustration show the developer movement directions within the machine. The developer that is attracted to the development roller [A] is split into two parts by the doctor blade [B]. One part (the magnetic brush) goes on to develop the latent image on the drum. However, the other part is trimmed off by the doctor blade and directed to the backspill plate [C].

As the developer slides down the backspill plate to the screw roller [D], part of the developer falls into the auger inlets [E] and is transported to the left side of the unit by the mixing auger [F], where it drops onto the paddle roller. As the paddle roller rotates, its blades move the developer to the right. The amount of developer moved to the right by the paddle roller is equal to the amount moved to the left by the mixing auger.

2-18

4.4 TONER DENSITY CONTROL

ID Sensor Check

Toner Sensor Check

6 January 1990

ID sensor normal?

Toner sensor normal?

Service Call indicator ON

Yes

Toner density low?

Yes

Toner supply solenoid ON

Original

longer than

1200 mm?

Yes

Toner density low?

Yes

Toner supply solenoid ON

The flow chart above illustrates how the copier determines whether or not to add toner.

This copier uses a dual sensor system to control toner density. The primary sensor is the ID sensor (image density sensor). This sensor is a photosensor and directly measures the density of the image on the drum using a test pattern. This is done just before making the copy. If the test pattern image density is too low, toner is added.

The secondary sensor is the toner sensor. It measures the ratio of toner to carrier in the developer. This sensor is used only if the output of the ID sensor is abnormal or the original is longer than 1200 millimeters. (For very long originals, it is possible for the toner density to change while the copy is being made.)

2-19

6 January 1990

4.4.1 Image Density Sensor

5.0

4.0

3.0

Voltage

(V)

2.0

1.0

0.5

LED Light Intensity

Weak Strong

4.0 0.2V

Standard Intensity

Threshold

Level

Toner is

supplied

No toner is supplied.

Toner density is detected by developing the sensor pattern and by checking its reflectivity with the image density sensor (photosensor). Light from the sensor’s LED reflects from the drum and activates the phototransistor. The output of the phototransistor goes to CN102-15 of the main board.

An average reference voltage (Vsg) is calculated from eight samples of bare drum reflectivity. After that, an average voltage is calculated from eight samples of sensor pattern reflectivity. These two values are then compared to determine whether toner should be added or not as follows.

No toner supply condition: Vsp/Vsg < 0.125 Toner supply condition: Vsp/Vsg > 0.125

ID Sensor [S2]

CN102

-14

-15

-12

Main PCB [PCB1]

+5V

CPU

CN104

-B10

+24 V

SOL 1

If Vsp/Vsg becomes greater than 0.225, the toner near end condition exists. The Add Toner indicator then starts flashing. When in the toner near end con-

2-20

6 January 1990

dition, 5.49 meters (=610 mm x 9) can be copied. After that, the toner end condition is reached. The Add Toner indicator will light and the machine will not operate.

The ID sensor checks toner density every 1220 mm. If Vsp/Vsg becomes greater than 0.125 (1/8), then it starts checking toner density every 610 mm. (If service program mode #21 is set to "1", the toner density will be checked every 610 mm regardless of Vsp/Vsg.)

The toner supply amount (%) can be adjusted using service program mode #17.

Using service program #34, Vsp, Vsg, and Vsp/Vsg can be displayed in the copy counter.

2-21

6 January 1990

4.4.2 Toner Density Sensor

Toner Density Sensor (S2) Main Board (PCB1)

Control

Circuit

1 2

3 4

Coils

CN101-1

[24V] Va

-2

-3

-4

Analog Input

[7.0V] (Control)

GND

The toner density sensor works in conjunction with the ID sensor to control the amount of toner in the developer mixture. It has three basic functions. First, it controls the upper and lower limits of toner density. For example, if the amount of toner in the developer is greater than the upper limit (analog input =

1.9 V), toner supply is prohibited no matter what the ID sensor input is. (Analog input of 3.5 V is the lower limit.) Second, it checks toner density if an original larger than 1220 mm is copied. Third, it takes over toner density control completely if the ID sensor becomes abnormal (=Vsp > 2.5 V or Vsg <

2.5 V). The toner density sensor is powered by 24 volts from CN101-1 of the main

board. The sensor’s sensitivity is set by the control signal applied from CN101-1. The input signal from the sensor is applied to CN101-2. This is an analog signal. When the toner density is at the standard level, the analog signal is approximately 2.1 volts.

The active sensing element is a very small transformer with three coils. When iron ferrite (carrier) is near the sensing element, the inductance of the coils changes, causing the current through the transformer to change. As the amount of toner in the developer increases, the effect of the carrier particles decreases and the voltage applied to CN101-2 decreases. Conversely, when the toner concentration drops due to use, the effect of the carrier on the sensor coils increases and the voltage at CN101-2 also increases. Service call "Ed" lights if the toner sensor output becomes less than 1.6 V or more than 4.7 V

2-22

6 January 1990

4.5 DEVELOPMENT BIAS

4.5.1 Basic Concept

When the drum is exposed, most of the negative charge is eliminated from the areas where light strikes the drum. This leaves a negative charge pattern corresponding to the dark areas of the original. After exposure however, a small residual charge of about --100 volts (for white paper) remains in the exposed areas. This residual charge could attract positively charged toner from the development roller and result in dirty background on the copy.

The development bias prevents such dirty background. A negative bias a little larger than the residual charge is applied to the development roller. This prevents the positively charged toner from being attracted to the background areas of the latent image.

Manual ID Bias

Bias (Volts)

-280

-240

-200

-180

-160

-120

1 2 3 4 5 6 7-14

Manual ID Setting

4.5.2 Manual Image Density Bias

When in manual image density mode, the development bias is applied as shown by the above chart.

In addition to the development bias, the image density is also controlled by varying the exposure light intensity. (See the exposure section.)

2-23

6 January 1990

Lighter ADS

-300

-260

-220

-200

Normal ADS

-280

-240

-200

-180

0.18 0.85

0.77

0.73

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Darker ADS

-260

-220

-180

-160

ADS Vod/Vsd

Vod: Original Density Detecting Voltage (ADS out put voltage) Vsd: Standard Pattern (White Plate) Density Detecting Voltage

4.5.3 Auto Image Density Bias

The above chart shows the development bias when in ADS mode. The ADS can be switched to the "Darker" setting with service program mode #20.

In addition to the development bias, the image density is also controlled by varying the exposure light intensity. (See the exposure section.)

4.5.4 Bias Adjustment

Bias Adjustment (Volts)

-40

-20 0

+20 +40

1 2 3 40

Program Mode #19

Using service program mode #19, the bias level can be increased or decreased as shown in the above chart.

2-24

6 January 1990

4.6 IMAGE DENSITY SENSOR BIAS

The ID sensor bias is similar to the development bias; however, it is applied only when developing the ID sensor pattern.

Basically, the ID sensor bias is fixed. The normal ID bias level is --240 volts, but it can be changed using service program #18. The following table shows the possible settings. You should clearly understand the effect of changing the ID sensor bias. If the ID sensor bias is increased the sensor pattern will become lighter. This will cause more toner to be added to the developer and thus copy images will become darker and toner consumption will increase. If the ID sensor bias is decreased, lighter images and less toner consumption will result.

Service Program #18

Setting 0 1 2 3

ID Bias --240 --200 --280 --320

Factory Setting

A developer counter correction is applied to the ID sensor bias to compensate for changes in the triboelectric properties of the developer as a new developer mixture is broken in. The following table shows this correction. Notice that the correction depends on the average Vsp/Vsg ratio as measured during initial conditioning as well as on the developer counter. By factoring in the initial conditioning Vsp/Vsg ratio, this correction compensates for slight variations between different lots of developer as well as for changes in the developer during the break-in period. After the initial conditioning, the copy counter will display the density level (dL).

Developer Counter Correction

Initial Conditioning

Vsp/Vsg

0--499 Copies 500--999 Copies More than 1000

Developer Counter

1 0--10 --40 V --20 V 0 V 2 10--15 --20 V 0 V 0 V 0 15--20 0 V 0 V 0 V 3 20--25 +20 V +20 V +20 V 4 >25 +40 V +40 V +40 V

NOTE: Perform the initial conditioning by SP#5 whenever the developer

mixture is replaced. Do not perform SP#5 when the drum is replaced. There is a possibility of dLE being displayed. This means that there was on ID sensor (Photo sensor) error during the initial conditioning.

2-25

6 January 1990

4.7 TONER SUPPLY

[C]

[B]

[A]

[B]

To allow a compact design, the toner supply mechanism is built into the toner cartridge. An agitator [A] in the toner cartridge turns when the toner supply solenoid is on (toner supply spring clutch engaged). As the agitator rotates, mylar strips [B] on the ends of the agitator force toner through small holes (0.5 mm) in a plastic strip [C] along one side of the toner cartridge. The toner particles thus ejected from the cartridge fall into the development unit and are mixed into the developer. The toner agitator turns at 120 rpm and the toner supply rate is approximately 36 grams per minute.

When supplying toner, the CPU turns on the toner supply solenoid the length of time required to supply the amount of toner specified by service program #17.

2-26

5. IMAGE TRANSFER AND PAPER SEPARATION

[A]

6 January 1990

[E]

[B]

[C]

[D]

5.1 PRE-TRANSFER LAMP (PTL)

After the latent image is developed but before the image is transferred to the copy paper, the drum surface is illuminated by the pre-transfer lamp [A]. This illumination reduces the negative potential on the drum surface. This prevents the toner particles from being re-attracted to the positively charged drum during the paper separation process. It also makes image transfer and paper separation easier.

5.2 IMAGE TRANSFER

The registration rollers [B] feed the copy paper through the transfer entrance guides to the transfer section. A high negative voltage (about --5.0 kV) is applied to the transfer corona wire [C], and the corona wire generates negative ions. These negative ions are applied to the copy paper, and the negative charge attracts the positive charged toner away from the drum and onto the paper. In addition, the paper is held against the drum by the positive counter charge on the drum.

5.3 PAPER SEPARATION

After image transfer, the copy must be separated from the drum. To break the attraction between the paper and the drum, the separation corona wires [D] apply an ac corona (4.0 kV) to the reverse side of the paper. The stiffness and weight of the paper causes it to separate from the drum.

The separation corona has a negative component of approximately --200 volts. This negative component holds the toner on the paper to prevent it from being reattracted to the drum during paper separation. The two pick-off pawls [E] ensure that thin paper, paper with low stiffness, or upward curled paper separates completely from the drum.

2-27

6 January 1990

5.4 PICK-OFF MECHANISM

[E]

[B]

[A]

[C]

[D]

The pick-off pawl solenoid [A] is energized 12 pulses after the registration solenoid turns on to feed the copy paper to the drum. The pick-off lever [B] then rotates clockwise and pushes up the pawl holder [C]. This releases the two pick-off pawls [D], allowing them to rotate against the drum.

Just after the leading edge of the copy paper passes the transport sensor, the pick-off solenoid turns off again. The pick-off spring [E] then pushes down the pawl holder, which moves the pick-off pawls away from the drum.

2-28

5.5 T/S CORONA CIRCUIT

6 January 1990

+24 (Va)

-5.0 kV

AC 4.0 kV DC -200 V

[P2]

DC/DC

Converter

DC/DC

Converter

DC/AC

Inverter

CN1-2

A. GND

CN1-1

[PCB1]

CN107CN1

-3

-B12

-4

-A13

-5

-B13

-6

-B11 Not Used

The T/S power pack is powered by +24 volts (Va) from the dc power supply. The dc/dc converters and dc/ac inverter change the +24 volts to the high voltages used by the transfer and separation coronas.

T. Trig

T. Sel

S. Trig

The main board (PCB1) turns on the transfer corona by dropping CN107-B12 (T.Trig) from 24 volts to 0 volt. This turns on the dc/dc converter, which applies a high voltage of approximately --5.0 kV to the transfer corona wire. The main board turns on the separation corona by dropping CN107-B13 (S.Trig) to 0 volt. The dc/dc converter and dc/ac inverter circuits then apply approximately ac 4.0 kV and --200 V to the separation corona wires.

Normally, T.Sel is not used. However, if the user presses the Auto Image Density key for longer than 3 seconds, the CPU uses both T.Trig and T.Sel to turn on the transfer corona. This increases the transfer corona current from 150 µA (the normal value) to 250 µA. The higher transfer current may be useful under high humidity conditions (When the higher transfer corona current is selected, the manual ID display function inverts.)

2-29

6 January 1990

6. CLEANING

6.1 OVERVIEW

[A]

[B]

The cleaning blade [A] removes any toner remaining on the drum after the image is transferred to the copy paper. The toner that is wiped off by the cleaning blade drops onto the toner collection coil [B], which then moves it to the used toner tank.

The cleaning blade pressure spring applies pressure to the exact center of the cleaning blade so that pressure is evenly applied across the entire length of the cleaning blade. Blade pressure is applied constantly; however, the blade pressure can be relieved manually for drum removal.

2-30

6.2 COLLECTION OF USED TONER

[A]

[C]

[E]

6 January 1990

[B]

[D]

The toner collection coil moves used toner from the cleaning unit through the used toner pipe [A] to the used toner tank [B]. The used toner tank can hold about 800 grams of toner. On average, about 10,000 A2 sized copies can be made before the used toner tank needs to be emptied. (This assumes 7% originals and 80% transfer efficiency.) The toner overflow sensor [C] detects when the used toner tank is full.

The toner collection bottle is vibrated to prevent used toner from building up in one place and activating the toner overflow sensor too early. The shaft of the first set of transport rollers has a cam [D] on the end. This cam is in contact with a projection [E] of the used toner bottle. It turns when the main motor is on and moves the used toner tank up and down as shown above right.

2-31

6 January 1990

6.3 TONER OVERFLOW SENSOR

+5 (Vc)

Toner Overflow Sensor 3]

[A]

[B]

Main Board

[PCB1]

CN107

-B22

0/5

OSC

Freq. Detec-

tion

Tr.

Rectifier

The toner overflow sensor [A] signals the CPU when the toner collection bottle is full.

A small tuning fork [B] is used as the sensing element of the toner overflow sensor. This tuning fork is a damping element in a multivibrator circuit. As long as there is nothing in contact with the tuning fork, the vibrating frequency of the circuit stays low and the transistor stays off.

When toner presses against the tuning fork, the resistance of the piezoelectric elements that are in contact with the tuning fork changes and the vibrating frequency increases. The frequency detection circuit passes the higher frequency signal to the rectifier which activates the switching transistor. The transistor sends a LOW signal to CN107-B22.

When the CPU detects this LOW signal, it stops the copier and lights the Toner Collection Bottle indicator.

2-32

7. QUENCHING

[A]

6 January 1990

[B]

+24 V

Quenching Lamp [2]

Main Board [PCB1]

CN104

-B8

(-B9)

After the drum is cleaned, light from the quenching lamp neutralizes any charge remaining on the drum. The quenching lamp turns on and off at the same time as the main motor.

The quenching lamp consists of two PCBs containing 49 LEDs (light emitting diodes) each. The LEDs output light in the 660 nm to 700 nm (red) range. The main board turns on the quenching lamp LEDs by dropping CN104-B8 and CN104-B9 to 0 volts. The two PCBs have identical circuits (shown above).

2-33

6 January 1990

8. PAPER FEED AND REGISTRATION

8.1 OVERVIEW

[B]

[A]

[D]

[C]

In this copier, paper is fed either manually or by the auto sheet feeder (option).

For manual feed, the copy paper is inserted until it contacts the manual feed rollers [A]. At that time the paper turns on the 1st feed detector [B], which causes the main motor to turn on. Two seconds after the main motor turns on, the manual feed solenoid turns on and the manual feed rollers start turning to feed the paper to the registration rollers [C]. If using the auto sheet feeder, copy paper feeds through the manual feed rollers automatically after the original is inserted.

Just before the paper reaches the registration rollers it activates the registration sensor [D]. The manual feed solenoid turns off 0.4 second after that. The 0.4 second delay allows the leading edge of the paper to align against the registration rollers (which are not turning at this time) to eliminate skew.

The registration clutch turns on to feed the paper to the drum. It is energized at the proper time to align the leading edge of the paper with the leading edge of the developed image on the drum.

Fine and coarse registration adjustments can be made using service program modes #26 and #27 respectively.

2-34

8.2 DRIVE MECHANISM

[A]

[B]

[F]

6 January 1990

[C]

[E]

[D]

Drive power from the main motor is provided to the paper feed and registration drive mechanism from feed/fusing drive belt 2 [A] through the manual feed/registration sprocket [B].

When the manual feed solenoid [C] is energized, the paper feed drive chain [D] drives the manual feed roller [E]. Once the paper reaches the registration sensor, the registration clutch [F] turns on, thus the registration roller [G] starts turning.

[H]

[G]

The manual feed/registration sprocket is in contact with the transport/fusing sprocket [H] which drives the transport and fusing units.

2-35

6 January 1990

9. PAPER TRANSPORT

[A]

[C]

[B]

[C]

[A]

[B]

After separation from the drum, the copy paper rides on the transport belts [A] and transport rollers [B] to the fusing unit.

Airflow directly from the vacuum fan [C] holds the paper firmly against the belts so that there is enough friction between the paper and the belts for smooth transportation of the paper. The transport belts and transport rollers are directly driven by the fusing drive chain (no clutch or solenoid); so, they turn constantly when the main motor is on.

2-36

10. FUSING AND PAPER EXIT

10.1 OVERVIEW

6 January 1990

[A]

[C]

[L]

[F]

[D]

[I]

[G]

[H]

[B]

[E]

Two rollers fuse the image to the copy paper by applying heat and pressure. The hot roller [A] is made of carbon-teflon and the pressure roller [B] is made of silicone rubber. Pressure is constantly applied by the pressure levers at the ends of the fusing unit.

The fusing lamp [C], which is located at the hot roller axis, is turned on and off to maintain the operating temperature. The temperature control circuit (on the main board) monitors the surface temperature of the hot roller and the pressure roller through thermistors [D and E respectively].

2-37

[J][K]

6 January 1990

The hot roller strippers [F] separate the copy from the hot roller and direct it to the fusing exit rollers [G]. After the fusing exit rollers, the exit gate [H] directs the copy to either the upper or lower exit rollers [I and J].

When the exit gate solenoid is on, the exit gate directs the copy paper down through the lower copy exit path. If the exit gate solenoid is off, the paper goes through the upper copy exit path. The exit direction is selected using the Copy Exit Way key.

A steel cleaning roller [K] removes toner from the pressure roller. This effectively cleans toner from both the hot roller and pressure roller because toner on the teflon surface of the hot roller sticks preferentially to the rubber of the pressure roller. Then, toner on the pressure roller sticks preferentially to the steel cleaning roller.

Two thermofuses (wired parallel) [L] provide backup overheat protection. (See the section on fusing temperature control.)

2-38

10.2 DRIVE MECHANISM

10.2.1 Fusing Drive

[A]

[C]

[D]

6 January 1990

[B]

[G]

[F]

[E]

The hot roller is turned by the fusing drive chain as shown. The pressure roller is friction driven by the hot roller. The fusing rollers turn constantly when the main motor [A] is on, driven via the gears [B], through feed/fusing drive belts 1 [C] and 2 [D], the sprockets [E] and the fusing drive chain [F], to the hot roller sprocket [G].

2-39

6 January 1990

10.2.2 Exit Roller Drive

[C]

[E]

[A]

[B]

[D]

The upper [A] and lower [B] exit rollers are driven by the main motor [C] via a set of gears [D]. Finally, the exit roller drive chain [E] drives the exit rollers through a sprocket as shown above.

The exit rollers turn constantly when the main motor is on.

2-40

10.3 FUSING TEMPERATURE CONTROL

6 January 1990

Overheat Protection

+24

IC107

1.3K

Q101

+24

A.GND

CN301

CN107-A25

CN107-A15

CN107-B25

AC Controller 1 [PCB3]

-5

-6

-3

RA 301

PC301

Drive Circuit

RA301

AC115,220,240

T304 T306

P U

CN110-12

CN110-11

CN110-9

T309 T310 T308 T307 T305

TH1

TH2

TF1

CN110-10

10.3.1 Fusing Circuit Operation

The fusing lamp is powered by AC controller 1 and controlled by the main board.

AC controller 1 receives direct wall voltage ac power (not stepped down) at T304 and T306. It also receives +24 volts at CN301-5. The ac power is applied to the drive circuit, the fusing lamp (L3), and the triac (TR). The dc power drives PC301 and RA301.

To turn on the fusing lamp, the main board drops CN107-A15 to LOW. This activates the photocoupler (PC301) which in turn energizes the drive circuit. The drive circuit turns on the triac to complete the lamp circuit, thus turning on the lamp.

RA301 guards against a failure of the +24 volt power supply. When +24 volts is applied at CN301-5, RA301 is energized and its ac contacts stay open. If the +24 volts power stops, the ac contacts of RA301 close, stopping the drive circuit and turning off the fusing lamp.

2-41

6 January 1990

10.3.2 Overheat Protection

The overheat protection circuit on the main board turns off the fusing lamp if the temperature goes too high.

The input from TH1 goes to pin 5 of IC107 as well as to the CPU. As the temperature of TH1 increases, its resistance decreases and therefore the voltage at pin 5 of IC107 increases. If this voltage becomes greater than the voltage at pin 6, the output at pin 7 becomes HIGH. Q101 then turns off and cuts the +24 volt supply to ac controller 2. The fusing lamp then turns off. The overheat protection circuit becomes effective at about 220 degrees.

TF1 (2 thermofuses in parallel) provides overheat protection in case a short bypasses the control and drive circuits. These two fuses will open if they reach approximately 192 degrees.

2-42

10.4 TEMPERATURE CONTROL

Hot Roller Temp.

195

190

SP #28

185

6 January 1990

180

175

170

165

160

75 80 85 90 95 100 105 110 115

Pressure Roller Temp.

SP #29

120

The main board monitors the temperature of the hot roller through TH1 and the temperature of the pressure roller through TH2. The CPU determines whether or not to turn on the fusing lamp based on the combination of the input from these two thermistors. If the pressure roller is cool, the CPU keeps the hot roller temperature high. However, if the pressure roller is hot, the CPU decreases the operating temperature of the hot roller. The above graph shows the relationship between the temperatures of the hot and pressure rollers.

The operating temperature of the hot roller and pressure roller can be adjusted using service programs #28 and #29. These programs are used to compensate for variations in the response of different thermistors. Service program #28 adjusts the hot roller temperature and service program #29 adjusts the pressure roller temperature. Both of these service programs shift the temperature in 2 degree increments. The maximum change is 10 degrees or --8 degrees. The fusing temperature can be monitored using service program #32.

Also. the setting for fusing warm-up cycle (after main switch on) can be adjusted using service program mode #14 to off or from one to three minutes, in one minute increments.

2-43

6 January 1990

11. OTHERS

11.1 PULSE GENERATOR

[S4]

CN112-1

Main Board [PCB1]

+5V

CPU CN112-3 CN112-2

The CPU controls the timing of all machine operations based on the number of pulses it receives from the pulse generator. Pulses are generated by rotating a disk with slots in it within a photointerruptor. As the disk rotates, light from the LED activates the phototransistor each time a notch comes between them. The pulse interval is 3.125 milliseconds.

If no pulses are received for one second during the copy cycle, the machine will stop and display "Eb" in the copy counter.

2-44

11.2 OPERATION PANEL

6 January 1990

MAIN BOARD (PCB1)

CN106

Scan1

Scan2

Scan3

Scan4

Scan5

Key 1 Key 2

Key 3 Seg a

Seg b Seg c

Seg d

Seg e

Seg f

Seg g

Seg h

-A11

-A13

-B11

-B13

-A12

CN106

-B15

-B16

-A16

-B7

-B6

-B5

-B4

-B3

-B2

-B1

-A1

CN201

-1

-2

-3

-4

-5

OPERATION PANEL (PCB7)

Key

Matrix

CN202

-1

-3

-2

LED Matrix

-4

-5 -6 -7-9-8 -10 -11

The above illustration shows the copier’s operation panel circuit in block form. The operation panel circuit is driven by five scan pulse lines. The copier uses

LEDs for displays elements. To light any particular LED, the CPU drops the appropriate segment line to 0 volt at the same time that the scan line connected to the LED is being energized.

The CPU monitors the KEY lines (KEY1 to KEY3) to determine if a key has been pressed. Each KEY line is used to monitor up to four keys on the operation panel. A specific scan pulse appears at the appropriate KEY line when a key on the operation panel is pressed.

2-45

6 January 1990

11.3 SOLENOIDS

Main Board [PCB1]

CN-1

[ +24]

SOL

CN-2

[+24] Va

To energize a solenoid, the main board drops CN-1 from +24 volts to 0 volt. The following table gives the main board connector numbers for the solenoids used in this machine.

Name Symbol CN-1 CN-2 Toner Supply SOL1 CN104-B10 CN104-A10 Pattern Shutter SOL2 CN104-B13 CN104-A13 Exit Gate SOL3 CN109-10 CN109-11 Pick-off SOL4 CN104-B11 CN104-A11 Paper Stopper SOL6 CN104-B12 CN104-A12 Manual Feed SOL7 CN107-B6 CN107-A6 Recycle Gate SOL8 CN106-B10 CN106-A10 Original Stopper SOL9 CN105-B7 CN105-A

2-46

11.4 PHOTOINTERRUPTORS

6 January 1990

Photointerrupter

Photo TR ON Output LOW

CN-1

CN-3

CN-2

Actuator Plate

Main Board (PCB1)

[+5V]

+5V

GND

Photo TR OFF Output OPEN

Photointerruptors consist of a plastic encapsulated LED and a phototransistor separated by an open slot. When the slot is empty, light from the LED activates the phototransistor, and the sensor outputs a low (0 volt) signal. When an actuator plate enters the slot, light from the LED is blocked and the output becomes open. In this machine a +5 volt pulse is present at CN-2 when the output is open.

This machine uses three different types of photointerruptor as shown above right. However, they all function in the same way.

The following table lists the photointerruptors used in this copier.

2-47

6 January 1990

Name Symbol CN-1 CN-3 CN-2 Pulse Generator S4 CN112-1 CN112-3 CN112-2 Original Set Detector S5 CN105-B4 CN105-A5 CN105-B5 1st Original

S6 CN105-B2 CN105-A3 CN105-B3

Transport Detector 2nd Original

S7 CN105-A1 CN105-B1 CN105-A2

Transport Detector Original Exit

S9 CN106-A17 CN106-B17 CN106-B18

Detector Recycle Gate

S10 CN106-A17 CN106-B14 CN106-B18

Detector 1st Feed Detector S11 CN104-B5 CN104-A6 CN104-B6 2nd Feed Detector S12 CN104-A4 CN104-B4 CN104-A5 Exit Detector S15 CN109-7 CN109-8 CN109-9

2-48

6 January 1990

12. SERVICE CALL CONDITIONS

When functional problems occur within the copier, the Call Service indicator ( ) lights. At the same time, "E" and a code number blink alternatively in the copy counter display.

CODE E1 (Abnormal Exposure Lamp)

Code E1 blinks if the output voltage of the light sensor drops below 0.45 volts and this condition continues for 20 seconds or more after the exposure lamp on signal is output.

CODE E2 (Fusing Thermofuse Open)

Code E2 blinks if the fusing temperature does not reach 100oC within 4 minutes after the main switch is turned on.

CODE E3 (Hot Roller Thermistor Open)

Code E3 blinks if the resistance of the thermistor (TH1) is 126.5 kΩ or more, 2 minutes after the fusing lamp turns on.

CODE E4 (Hot Roller Thermistor Short)

Code E4 blinks if the resistance of the thermistor (TH1) is 0.1 kΩ or less, 2 minutes after the fusing lamp turns on.

CODE E5 (Pressure Roller Thermistor Open)

Code E5 blinks if the resistance of the thermistor (TH2) is 1 mΩ or more, 2 minutes after the fusing lamp turns on.

CODE E6 (Pressure Roller Thermistor Short)

Code E6 blinks if the resistance of the thermistor (TH2) is 0.5 kΩ or less, 2 minutes after the fusing lamp turns on.

CODE E7 (Exposure Lamp Thermistor Open)

Code E7 blinks if the resistance of the thermistor becomes 248 Ω or more, and if this condition continues for 20 seconds.

CODE E8 (Exposure Lamp Thermistor Short)

Code E8 blinks if the resistance of the thermistor becomes 2.4 Ω or less, and if this condition continues for 20 seconds.

CODE E9 (Fusing Overheat)

Code E9 blinks if the hot roller temperature reaches 200oC.

2-49

6 January 1990

CODE EA (Ready Failure)

Code EA blinks if the machine does not reach the ready condition (Ready indicator ON) within 14 minutes after the main switch is turned on.

CODE Eb (Abnormal Drive)

Code Eb blinks if the pulse generator does not generate pulses for 1 second after the main motor turns on.

CODE Ec (Abnormal Total Counter)

Code Ec blinks if the relay in the counter does not turn on or off when the counter counts up.

CODE Ed (Abnormal Toner Density Sensor)

Code Ed blinks if the sensor voltage (Vts) becomes less than 1.6 volts or more than 4.7 volts for 1 minute.

CODE EF (Abnormal Condition in ID Sensor)

Code EF blinks if the ID sensor (photosensor) bare drum voltage (Vsg) becomes less than 2.5 volts, or the sensor pattern voltage (Vsp) becomes more than 2.5 volts.

NOTE: a) Codes E2, E3, E4, E5, E6, E8,E9, EA, Ec and Ed are indicated

immediately when the abnormal condition occurs and the machine stops.

b) Codes E1, E7,Eb and EF are not displayed when the condition

occurs. Copies can be made, but image quality may be degraded. Check for these conditions using service program #58 to #61.

2-50

SECTION 3

INSTALLATION

6 January 1990

1. ENVIRONMENT

1. Temperature Range: 10oC to 30oC (50oF to 86oF)

2. Humidity range: 15% to 90% RH

3. Ambient Illumination: Less than 1,500 Lux (do not exposure to direct sunlight).

4. Ventilation: Room air should turn over at least 3 times/hour.

5. Ambient Dust: Less than 0.15 mg/m3 (4 x 10 oz/yd3)

6. Room Size: More than 10 m3 (13.4 yd3)

7. If the installation place is air-conditioned or heated, place the machine as

follows:

a) Where it will not be subjected to sudden temperature changes

from low to high, or vice versa.

b) Where it will not be directly exposed to cool air from an air

conditioner in the summer.

c) Where it will be directly exposed to reflected heat from a space

heater in the winter.

8. Avoid placing the machine in an area filled with corrosive gases.

(Ammonia level should be less than 5 PPM.)

9. Avoid any area higher than 2,000 m (6,500 ft) above sea level.

-3

10. Place the machine on a strong and level base.

11. Avoid any area where the machine may be subjected to frequent strong

vibration.

3-1

6 January 1990

1.1 MINIMUM SPACE REQUIREMENTS

600 mm

1000 mm

1. Front: 1,000 mm (39.5 in)

2. Back: 600 mm (24 in)

3. Right: 600 mm (24 in)

4. Left: 600 mm (24 in)

3-2

1.2 POWER SOURCE

1. Input Voltage Level: 115 V/60 Hz....12A

220 V/50 Hz....7A

240 V/50 Hz....7A

6 January 1990

2. Permissible Voltage

±10%

Fluctuation:

3. Permissible Extension Cord: At least 300 V, 30 A capacity and less than 5 m (5.5 yd) long.

NOTE: a) Be sure to ground the machine. (Do not connect the grounding

wire to a gas pipe.)

b) Make sure the plug is firmly inserted in the outlet.

c) Avoid multi-wiring.

d) Do not set anything on the power cord.

3-3

6 January 1990

2. ACCESSORY CHECK

Check the accessories and their quantities according to the following list:

1. Copy Guide.............................................................................1 pc

2. Original Guide.........................................................................2 pcs

3. Left Inner Cover Bracket.........................................................1 pc

4. Pick-off Pawl Unit....................................................................1 pc

5. Right Inner Cover....................................................................1 pc

6. Left Inner Cover......................................................................1 pc

7. Inner Cover Bracket................................................................1 pc

8. Pan-head Screw (M4 x 6).......................................................16 pcs

9. Flat-head Screw (M4 x 6) .......................................................3 pcs

10. Fixing Plate.............................................................................1 pc

3-4

3. INSTALLATION PROCEDURE

3.1 REMOVAL OF SHIPPING RETAINERS

1. Remove all strips

of shipping tape and accessories.

6 January 1990

2. Open the original

feed unit [A] and remove the two spacers [B] from the platen roller bearings, and remove the protective sheet from the exposure glass.

3-5

6 January 1990

3. Loosen four screws

and remove the right middle cover [C].

4. Remove the screw

[D] fixing the main board bracket [E] and open the board 90 degrees.

5. Remove the plate

[F] (4 screws), fixing the right portion of the upper unit on the lower unit. (Keep two screws for mounting the fixing plate later.)

6. Loosen four screws

and remove the left middle cover.

3-6

7. Remove the screw

[G] fixing the left portion of the upper unit on the lower unit.

8. Press up the handle

[A] and open the middle unit [B].

6 January 1990

9. Install the fixing

plate [C] with the two screws. Then, reinstall the main board bracket.

3-7

6 January 1990

3.2 MOUNTING THE ACCESSORIES

1. Mount the left inner

cover bracket [A] with two screws.

2. Connect the two

connectors [B] of the pick-off pawl unit [C] and fix the unit with two knob screws [D]. Make sure that the two positioning pins of the main copier are inserted in the two holes of the pick-off pawl unit.

3. Remove the drum

protection sheet [E] by turning portion [F] of the main motor counterclockwise.

CAUTION: Make sure that no tape is left on the drum.

3-8

4. Reset the cleaning

blade by pulling the release lever [G] towards the front side.

5. Close the middle

unit and open the retention unit.

6. Open the toner car-

tridge cover [H].

7. Place a level [I] in

the space between the cartridge cover and the developer entrance.

6 January 1990

8. Adjust the level of

the machine by turning the bolts on the 4 machine feet.

3.3 SUPPLYING DEVELOPER (3 kg)

1. Open the original

feed unit and the toner cartridge cover [A].

2. Remove the sponge

seal [B] from the developer entrance.

3. Plug the power sup-

ply cord into the wall outlet (socket).

3-9

6 January 1990

4. Turn on DIP SW

101-7 and 8 on the main board [C].

5. Turn on the main

switch [D].

6. Pour of developer

into the development unit evenly as shown.

7. Close the cartridge

cover and the original feed unit.

8. Press the Lighter

key once.

9. Press the Copy Exit

Way key [E] to turn on the development motor. Press the Copy Exit Way key again after 2 or 3 seconds to turn the motor off.

10. Repeat steps 8

through 9 until 3 kg of developer has been loaded in the development unit.

11. Turn off the main

switch and DIP SW 101-7 and 8.

3-10

3.4 SUPPLYING TONER

6 January 1990

1. Set the toner car-

tridge [A] as shown in the figure.

2. Remove the sealing

tape [B] on the cartridge and turn the knob [C] clockwise unit it stops.

3-11

6 January 1990

3.5 INITIAL CONDITIONING

1. Connect the power

supply cord with the wall outlet (socket).

2. Turn on DIP SW

101-8.

3. Turn on the main

switch.

4. Press the Lighter

key [A] four times so that the fourth segment from the right of the copy density indicator lights.

5. Press the Plus key

[B] once then press the Paper Exit Select key [C].

6. Turn off DIP SW

101-8 to start initial conditioning. (Initial conditioning stops automatically when it is complete.)

3-12

3.6 MOUNTING THE COVERS

1. Press up the re-

lease handle [D] and open the upper unit.

2. Install the right in-

ner cover [E] and the bracket [F] on the lower unit. (Use 2 pan-head screws for the bracket. Use 1 flat-head screw and 3 pan-head screws for the right inner cover.)

6 January 1990

3. Install the right mid-

dle cover. (4 screws)

4. Install the left inner

cover [G] on the lower unit. (2 flathead and 5 panhead screws)

5. Install the left mid-

dle cover. (4 screws)

3-13

6 January 1990

3.7 MOUNTING GUIDES

1. Install the copy

guide [A]. Use the two screws that are already in the correct position on the top unit.

2. Set the two original

guides [B] as shown in the figure.

3-14

SECTION 4

SERVICE TABLES

6 January 1990

1. PREVENTIVE MAINTENANCE SCHEDULE

Symbol key: I = Inspect L = Lubricate R = Replace A = Adjust C = Clean

A. Original Feed_________________________________________________

EM 3.6km 7.2km 10.8km 14.4km 18km Notes

(6k) (12k) (18k) (24k) (30k)

1. Front original feed

roller

2. Rear original feed

roller

3. Original registration

rollers

4. Platen roller C C C C C C Clean with a

5. Press rollers I C C Clean with a

6. White plate C C C C C C Clean with a

7. AD sensor C C C C C Clean with a

8. Timing belts I I I I I Adjust if nec-

9. Original table C C C C C C Clean with

C C Clean with a

damp cloth

C C Clean with a

damp cloth

C C Clean with a

damp cloth

blower brush

essary

water or isoprophyl alcohol

B. Optics_______________________________________________________

EM 3.6km 7.2km 10.8km 14.4km 18km Notes

(6k) (12k) (18k) (24k) (30k)

1. Fiber optic array Clean with

lens paper when necessary

2. Exposure lamp Clean with a

damp cloth if necessary.

3. Exposure glass C C C C C C Water or

glass cleaner

4-1

6 January 1990

C. Development _________________________________________________

EM 3.6km 7.2km 10.8km 14.4km 18km Notes

(6k) (12k) (18k) (24k) (30k)

1. Developer R

2. Side seals I I I I I Replace if damaged

3. Development filter R R

D. Around Drum_________________________________________________

EM 3.6km 7.2km 10.8km 14.4km 18km Notes

(6k) (12k) (18k) (24k) (30k)

1. Corona wires C C C C C C Clean with a dry cloth. Replace at 20 K (if necessary)

2. Grid wires C C C C C C Clean with a dry cloth

3. Charge corona end-

block casing

4. T/S corona end-

block casing

5. Ozone filter R R R R R

6. Quenching lamp I I I I C Clean with a

7. Pick-off pawls C C C C C Clean with a

8. Pre-transfer lamp C C C C C Clean with a

9. ID sensor C C C C C Clean with a

10. Transfer guide

plate

C C C C C C Clean with a

I I I I I

C C Clean with a

dry cloth

dry cloth or blower brush

dry cloth

dry cloth.

dry cloth or blower brush

E. Cleaning_____________________________________________________

EM 3.6km 7.2km 10.8km 14.4km 18km Notes

(6k) (12k) (18k) (24k) (30k)

1. Cleaning blade C C C C C Clean with toner coated finger as necessary. Replace at 40K A1 size copies.

2. Cleaning seal I I I I I

3. Used toner tank I I I I I I

4-2

6 January 1990

Clean when necessary.

F. Paper Feed __________________________________________________

EM 3.6km 7.2km 10.8km 14.4km 18km Notes

(6k) (12k) (18k) (24k) (30k)

1. Transport belt C C C C C Clean with a damp cloth

2. Manual feed rollers C C C C C Clean with a damp cloth

3. Manual feed table C C C C C Clean with a damp cloth

4. Registration rollers C C C C C Clean with a damp cloth

5. Spring clutch L Lubricate with Mobil Temp. 78.

6. Registration roller

brake

I I I I I

G. Fusing ______________________________________________________

EM 3.6km 7.2km 10.8km 14.4km 18km Notes

(6k) (12k) (18k) (24k) (30k)

1. Hot roller Replace at 48K A1 size copies if necessary.

2. Pressure roller Replace at 120K A1 size copies if necessary.

3. Cleaning roller C Suitable solvent

4. Fusing thermistor C Suitable solvent

5. Hot roller strippers C Suitable solvent

6. Fusing/exit guide

plate

Clean as needed with a damp cloth

4-3

6 January 1990

H. Auto Sheet Feeder ____________________________________________

EM 3.6km 7.2km 10.8km 14.4km 18km Notes

(6k) (12k) (18k) (24k) (30k)

1. Feed roller I C C C C C Replace at 40K (A1) if necessary. Clean with a damp cloth.

2. Friction pad I C C C R C Clean with a damp cloth.

3. Bottom plate pad Replace at 40K (A1) if necessary

4. Relay rollers C C C C C Clean with a damp cloth

5. Paper feed guide

plate

6. Spring clutch L Lubricate

7. Teflon tape R

Clean with a damp cloth as needed.

with Mobil Temp. 78.

I. Others _______________________________________________________

EM 3.6km 7.2km 10.8km 14.4km 18km Notes

(6k) (12k) (18k) (24k) (30k)

1. Timing belts I I I I I Adjust the tension if necessary.

2. Chains I L I L I Adjust the tension if necessary. Lubricate with Mobil Temp. 78.

3. Gears I L I L I Lubricate with Mobil Temp. 78.

4-4

2. TEST PINS, VRs, AND DIP SWITCHES

2.1 TEST PINS AND VARIABLE RESISTORS

TP# VR# Function 101 101 Original registration sensor 102 104 ID sensor 103 105 Toner density sensor 104 103 Auto density sensor (ADS) 105 102 Light sensor 106 ---- Ground 107 ---- Vc (+5 volts) 108 ---- Va (+24 volts)

2.2 DIP SWITCHES

6 January 1990

NO. OFF ON 1 Normal Free run (one A1 sideways feed cycle,

feed original to start.) 2 Normal Forced Ready condition (no warm-up) 3 Length counter Copy counter 4 Millimeters* Inches** 5 Normal Clear counter memory*** 6 Normal Input check 7 Normal Output check 8 Normal Service program mode

*Counts up one per meter **Counts up one per yard ***Service counters for jams

4-5

6 January 1990

3. SERVICE TOOLS

3.1 SERVICE PROGRAM MODE

1 2 3 4 5 6 7 8

The service program mode allows you to select or adjust many machine and copy functions from the operation panel.

3.1.1 Access Procedure

1. Turn OFF the main switch

2. Turn ON DIP101-8 on the main board.

3. Turn ON the main switch.

•• The Call Service ( ) and Add Toner ( ) indicators will blink. This is

to confirm that the correct mode has been selected.

4. Select the appropriate image density level and lead edge erase amount.

5. Set the appropriate number in the copy counter using the Plus and Minus keys.

6. Press the Copy Exit Way key.

3.1.2 Service Program Table

Number

ID Setting (1) Lead Edge

Lighter Copy

Auto Image Density

Erase

20 mm 15 mm 10 mm

5 mm

Function

Exposure Lamp OFF (2)

0 ...Normal 1 ...Exp. lamp OFF

Jam Check OFF (2) 0 ...Jam check ON

1 ...Jam check OFF

Toner Sensor Control 0 ...Normal

1 ...Toner sensor control canceled

4-6

6 January 1990

Service Program Table Contd.

Number

ID Setting (1) Lead Edge

Lighter Copy

1 2 3 4 5 6 7 8

Auto Image Density

Erase

20 mm 15 mm 10 mm

5 mm

Function

Initial Conditioning 0 ...Normal 1 ...Initial Conditioning After set-up, turn off DIP101-8 to start initial conditioning. The machine will stop automatically when it is complete.

All indicators ON (2) Press Copy Exit Way

key to turn indicators ON. Press [C/S] to cancel.

Auto Reset Time 0 ...2 minutes 1 ...1 minute 2 ...3 minutes 3 ...4 minutes 4 ...5 minutes 5 ...No auto reset

Count UP/DOWN 0 ...Count UP

1 ...Count DOWN

Lighter Copy

Auto Image Density

4-7

20 mm 15 mm 10 mm

5 mm

20 mm 15 mm 10 mm

5 mm

20 mm 15 mm 10 mm

5 mm

Key Tone 0 ...Key tone ON

1 ...Key tone OFF

Default ID Setting 0 ...Auto ID sensing

1 ...Manual ID level 4

Default Paper Feed 0 ...Auto Sheet Feeder

1 ...Manual Feed

6 January 1990

Service Program Table Contd.

Number

ID Setting (1) Lead Edge

Lighter Copy

1 2 3 4 5 6 7 8

Auto Image Density

Erase

20 mm 15 mm 10 mm

5 mm

Function

Default Paper Exit 0 ...Upper Exit

1 ...Lower Exit

Auto Sheet Feeder (ASF) 0 ...ASF installed 1 ...ASF not installed

Fusing Warm-up Cycle 0 ..No warm-up cycle 1 ..1 minute 2 ..2 minutes 3 ..3 minutes

Lead or Trail Edge Erase 0 ...Leading edge erase 1 ...Trailing edge erase

Lighter Copy

Auto Image Density

20 mm 15 mm 10 mm

5 mm

20 mm 15 mm 10 mm

5 mm

20 mm 15 mm 10 mm

5 mm

20 mm 15 mm 10 mm

5 mm

Toner Supply Amount 0 ...15% 1 ...7.5% 2 ...30% 3 ...60%

ID Sensor Bias 0 ...--240 V 1 ...--200 V 2 ...--280 V 3 ...--320 V (During initial conditioning the ID Sensor Bias is

--340 V) Dev. Bias Adjustment

0 ...0 1 ...+40 V 2 ...+20 V 3 ...--20 V 4 ...--40 V

ADS Basic Level Setting 0 ...Normal 1 ...Lighter 2 ...Darker

4-8

6 January 1990

Service Program Table Contd.

Number

ID Setting (1) Lead Edge

Lighter Copy

1 2 3 4 5 6 7 8

Auto Image Density

Erase

20 mm 15 mm 10 mm

5 mm

Function

ID Sensing Interval 0 ...1220 mm (Normal) 1 ...610 mm

ID Sensor Grid Voltage Adjustment 0 ...--460 V 1 ...--380 V 2 ...--400 V 3 ...--420 V 4 ...--440 V 5 ...--480 V 6 ...--500 V

Copy Grid Voltage Adjustment 0 ... 0 V 1 ...+40 V 2 ...+20 V 3 ...--20 V 4 ...--40 V

PTL OFF (trailing edge) 0 ...PTL ON (Factory

.....setting)

1 ...+10 mm 2 ...+5 mm 3 ... 0 mm 4 ...--5 mm 5 ...--10 mm 6 ...--15 mm 7 ...--20 mm 8 ...--25 mm 9 ...--30 mm

Fine Registration Adjustment (0.25 mm/step) 0 ...0 mm 1 ...--1.0 mm 2 ...--0.75 mm 3 ...--0.5 mm 4 ...--0.25 mm 5 ...+0.25 mm 6 ...+0.5 mm 7 ...+0.75 mm 8 ...+1.0 mm

4-9

6 January 1990

Service Program Table Contd.

Number

ID Setting (1) Lead Edge

Lighter Copy

1 2 3 4 5 6 7 8

Auto Image Density

Erase

20 mm 15 mm 10 mm

5 mm

Function

Coarse Registration Adjustment (1 mm/step) 0 ...0 mm 1 ...--5 mm 2 ...--4 mm 3 ...--3 mm 4 ...--2 mm 5 ...--1 mm 6 ...+1 mm 7 ...+2 mm 8 ...+3 mm 9 ...+4 mm

Fusing Temperature Hot Roller Adjustment

0 ...0

1 ...--8 2 ...--6 3 ...--4 4 ...--2 5 ...+2 6 ...+4 7 ...+6 8 ...+8 9 ...+10

Pressure Roller Temperature Adjustment 0 ... 0

1 ...--8 2 ...--6 3 ...--4 4 ...--2 5 ...+2 6 ...+4 7 ...+6 8 ...+8 9 ...+10

Fusing Roller/Pressure Roller Temperature Display F: Fusing roller P: Pressure roller

4-10

6 January 1990

Service Program Table Contd.

Number

ID Setting (1) Lead Edge

Lighter Copy

1 2 3 4 5 6 7 8

Auto Image Density

Erase

20 mm 15 mm 10 mm

5 mm

Function

ID Sensor Vsg Adjustment. Adjust with VR104 and TP102. Adjust to

4.0

±0 volts

ID Sensor Vsg/Vsp Check A = Vsp C = Vsg F = Vsp/Vsg

Toner Sensor Adjustment Adjust with VR105 and TP103. Use new developer and adjust to 4.0V.

Toner Sensor Voltage Display.

Lighter Copy

Auto Image Density

20 mm 15 mm 10 mm

5 mm

20 mm 15 mm 10 mm

5 mm

20 mm 15 mm 10 mm

5 mm

20 mm 15 mm 10 mm

5 mm

20 mm 15 mm 10 mm

5 mm

White Level (Vsd) ADS Adjustment. Adjust with VR103 and TP104. Adjust to

3.0

± 0.1 V.

ADS Check. A = Vod (Original Density) B = Vsd (White Plate) F = Vod/Vsd.

Endless Repeat 0 ...Normal 1 ...Endless

Total Original Jams

Original Jams: Upper Transport

4-11

6 January 1990

Service Program Table Contd.

Number

ID Setting (1) Lead Edge

Lighter Copy

1 2 3 4 5 6 7 8

Auto Image Density

Erase

20 mm 15 mm 10 mm

Function

Original Jams: Turn Section

5 mm

Original Jams: Lower Transport

5 mm

Original Jams: Recycle Gate

5 mm

Original Jams: Others

5 mm

Lighter Copy

Auto Image Density

20 mm 15 mm 10 mm

5 mm

20 mm 15 mm 10 mm

5 mm

20 mm 15 mm 10 mm

5 mm

20 mm 15 mm 10 mm

5 mm

20 mm 15 mm 10 mm

5 mm

Total Paper Jams

Auto Feed Jams

Manual Feed and Registration Jams

Pick-off Jams

Exit Jams

4-12

Ricoh FW810 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

1. SPECIFICATIONS

2. OPERATOR CONTROLS

2.1 OPERATION PANEL

2.2 INDICATOR PANEL

3. DRUM PROCESSES

4. MECHANICAL COMPONENT LAYOUT

5. DRIVE LAYOUT

6. ELECTRICAL COMPONENT LAYOUT

6.1 MIDDLE AND UPPER SECTIONS

6.2 LOWER AND FUSING SECTIONS

7. ELECTRICAL COMPONENT DESCRIPTIONS

8. AC POWER DISTRIBUTION

9. DC POWER SUPPLY

DETAILED SECTION DESCRIPTIONS

1. DRUM

1.1 DRUM CHARACTERISTICS

1.2 HANDLING THE DRUM

1.3 DRUM DRIVE

2.1 OVERVIEW

Charge

2.2 CHARGE CORONA CIRCUIT

3. EXPOSURE

3.1 OVERVIEW

3.2 ORIGINAL FEED

3.2.1 Basic Operation

3.2.2 Drive Mechanism

3.3 ORIGINAL STOPPER MECHANISM

3.4 EXPOSURE LAMP CONTROL

3.5 MANUAL ID CONTROL VS ADS

3.5.1 Manual ID Control

3.5.2 ADS Control

3.6 AUTO DENSITY SENSOR (ADS)

3.7 LAMP HEATER

3.8 LAMP HEATER CONTROL CIRCUIT

4. DEVELOPMENT

4.1 OVERVIEW

4.2 DRIVE MECHANISM

4.3 CROSS MIXING

4.4 TONER DENSITY CONTROL

4.5 DEVELOPMENT BIAS

4.5.1 Basic Concept

4.5.2 Manual Image Density Bias

4.5.3 Auto Image Density Bias

4.5.4 Bias Adjustment

4.6 IMAGE DENSITY SENSOR BIAS

4.7 TONER SUPPLY

5. IMAGE TRANSFER AND PAPER SEPARATION

5.1 PRE-TRANSFER LAMP (PTL)

5.2 IMAGE TRANSFER

5.3 PAPER SEPARATION

5.4 PICK-OFF MECHANISM

5.5 T/S CORONA CIRCUIT

6. CLEANING

6.1 OVERVIEW

6.2 COLLECTION OF USED TONER

6.3 TONER OVERFLOW SENSOR

7. QUENCHING

8. PAPER FEED AND REGISTRATION

8.1 OVERVIEW

8.2 DRIVE MECHANISM

9. PAPER TRANSPORT

INSTALLATION

1. ENVIRONMENT

1.1 MINIMUM SPACE REQUIREMENTS

1.2 POWER SOURCE

2. ACCESSORY CHECK

3. INSTALLATION PROCEDURE

3.1 REMOVAL OF SHIPPING RETAINERS

3.2 MOUNTING THE ACCESSORIES

3.3 SUPPLYING DEVELOPER (3 kg)

3.4 SUPPLYING TONER

3.5 INITIAL CONDITIONING

3.6 MOUNTING THE COVERS

3.7 MOUNTING GUIDES

SERVICE TABLES

1. PREVENTIVE MAINTENANCE SCHEDULE