MINOLTA Di 850 Service Manual

Service Manual

[General]

Di850

Dual references may be used on the following:

Official O pti ons name : Popular Op ti ons name

EDH-5 : RADF

C-403/C-40 4 : LT and LCT

FN-115 : FNS

FN-7 : FNS

Cove r I nserte Cr : PI

PK-3 : PU

TMG-2 TU

ZK-2 : PZ

In-System Writer : ISW

CONTENTS

CONTENTS

SAFETYANDIMPORTANTW ARNINGITEMS

. . . . S-1

IMPORTANTNOTICE . . . . . . . . . . . . . . . . . S-1

DANGER,WA RN ING,AND CAUTION
SYMBOLSANDEXPRESSIONS . .S-1

SAFETYWARNINGS . . . . . . . . . . . . . . . . . . S-2

SAFETYINFORMATION

. . . . . . . . . . . . . . . . . S-9

IMPORTANTINFORMATION . . . . . . . . . . . S-9

SAFETYCIRCUITS . . . . . . . . . . . . . . . . . . .S-10

INDICATIONOFWARNINGONTHE
MACHINE

. . .S-12

1.OUTLINE

OUTLINE OF SYSTEM ...... ..... ................................ ..1-1

PRODUCT SPECIFICATIONS..................................1-2

CENTER CROSS-SECTIONAL VIEW......................1-4

DRIVE SYSTEM DIAGRAM.................................... ..1-5

[1] Main Drive Section .....................................1-5

[2] Drum Drive Section......................... ..... ......1-6

[3] Developing Drive Section...........................1-7

[4] Paper Feed Drive Section..........................1-7

[5] Tray 1 and 2 Pape r Feed Drive Secti on .....1-8

[6] Tray 3 Paper Feed Drive Section ...............1-9

[7] Vertical Conveyance Drive Section..........1-10

[8] By-pass Paper Feed Drive Section..........1-11

[9] Conveyance/Transfer and Separation

Wire Cleaning Drive Section ....................1-12

[10] ADU Conveyance Drive Section ..............1-13

[11] Paper Exit Drive Section ..........................1-14

[12] Toner Supply Drive section......................1-14

[13] Optics Drive Section.................................1-15

[14] Web Drive Section....................................1-16

2.UNIT EXPLANATION

EXTERNAL SECTION...........................................2-A-1

[1] Composition ...........................................2-A-1

DRIVE SECTION....................................... ..... .......2-B-1

[1] Composition ...........................................2-B-1

[2] Mechanisms ...........................................2-B-1

[3] M1 (Main) Control...................................2-B-2

[4] M2 (Drum) Control..................................2-B-2

READ SECTION....................................................2-C-1

[1] Composition ...........................................2-C-1

[2] Mechanisms ...........................................2-C-1

[3] M13 (Scanner Drive) Control..................2-C-2

[4] Exposure control ....................................2-C-4

[5] Original Read Control.............................2-C-5

[6] APS Control............................................2-C-5

[7] AE Control..............................................2-C-7

WRITE UNIT..........................................................2-D-1

[1] Composition ...........................................2-D-1

[2] Mechanisms ...........................................2-D-1

[3] M17 (Polygon) Control ...........................2-D-2

[4] Image Write Control ...............................2-D-4

DRUM UNIT............................. .... ..........................2-E-1

[1] Composition ...........................................2-E-1

[2] Mechanisms ...........................................2-E-1

[3] Separation Claw Control ................. ..... ..2-E-2

[4] Paper Guide Plate Control .....................2-E-2

[5] Drum Potential Control...........................2-E-3

CORONA UNIT SECTION......................... ..... ..... ..2-F-1

[1] Composition ...........................................2-F-1

[2] Mechanisms ...........................................2-F-1

[3] Charging Control ....................................2-F-2

[4] Transfer/Separation Control...................2-F-3

[5] M23 (Charger Cleaning) Control............2-F-4

[6] M18 (Transfer/Separation Cleaning)

Control....................................................2-F-5

3 DIS./ASSEMBLY1 OUTLINE2 UNIT EXPLANATION

CONTENTS

[7] PCL/TSL Control ....................................2-F-6

DEVELOPING UNIT .............................................2-G-1

3 DIS./ASSEMBLY1 OUTLINE3 DIS./ASSEMBLY2 UNIT EXPLANATION

[1] Composition........................................... 2-G-1

[2] Mechanisms.......................................... 2-G-1

[3] M3 (Developing Unit Drive) Control....... 2-G-2

[4] Developing Bias Control........................2-G-2

[5] Toner Density Control............................2-G-3

[6] Dmax Control......................................... 2-G-4

[7] Gradation Correction Control................. 2-G-6

[8] Dot Diameter Correction Control........... 2-G-7

[9] FM2 (Developing Suction) Control........ 2-G-8

TONER SUPPLY UNIT..........................................2-H-1

[1] Composition............................................2-H-1

[2] Mechanisms ...........................................2-H-1

[3] Toner Level Detection Control................2-H-2

[4] M11 (Toner Supply 1) Control................2-H-3

CLEANING/TONER RECYCLE UNIT....................2-I-1

[1] Composition.............................................2-I-1

[2] Mechanisms ............................................2-I-1

[3] M14 (Blade) Control ................................2-I-2

TRAY 1/2 PAPER FEED UNIT..............................2-J-1

[1] Composition............................................ 2-J-1

[2] Mechanisms ...........................................2-J-1

[3] First Paper Feed Control........................2-J-3

[4] Paper Up Drive Control .......................... 2-J-5

[5] Paper Size Detection Control.................2-J-7

[6] No paper detection control..................... 2-J-8

TRAY 3 PAPER FEED UNIT.................................2-K-1

[1] Composition............................................2-K-1

[2] Mechanisms ...........................................2-K-1

[3] First Paper Feed Control........................2-K-3

[4] Paper Up Drive Control ..........................2-K-4

[5] Paper Size Detection Control.................2-K-5

[6] No paper detection control.....................2-K-5

BY-PASS TRAY.....................................................2-L-1

[1] Composition............................................2-L-1

[2] Mechanisms ...........................................2-L-1

[3] First Paper Feed Control........................2-L-2

[4] Paper Up/down Control..........................2-L-3

[5] Paper Size Detection Control.................2-L-4

[6] No paper detection control.....................2-L-4

VERTICAL PAPER CONVEYANCE SECTION.... 2-M-1

[1] Composition........................................... 2-M-1

[2] Mechanisms..........................................2-M-1

[3] Vertical Paper Conveyance Control...... 2-M-2

ADU.......................................................................2-N-1

[1] Composition............................................2-N-1

[2] Mechanisms ...........................................2-N-2

[3] Loop/Second Paper Feed Control..........2-N-9

[4] Paper Conveyance Control ..................2-N-10

[5] Paper Reverse and Exit Control...........2-N-11

[6] ADU Paper Feed/Reversal Control......2-N-13

[7] ADU Paper Conveyance/Feed

Control..................................................2-N-15

FIXING UNIT.........................................................2-O-1

[1] Composition ...........................................2-O-1

[2] Mechanisms ...........................................2-O-2

[3] M16 (Web Drive) Control .......................2-O-5

[4] Fixing Temperature Control ...................2-O-6

[5] SD3 (Fixing Guide) Control....................2-O-8

OTHER KINDS OF CONTROL ...... .... ...................2-P-1

[1] Parts Energized when the Main

Switch is OFF.........................................2-P-1

[2] Parts that Operate when the SW1

(Main) is Turned ON...............................2-P-2

[3] Cooling Fan Control ...............................2-P-3

[4] Operation Panel Control.........................2-P-6

[5] Counter Control......................................2-P-8

[6] Option Control........................................2-P-9

SAFETY AND IMPORT ANT WARNING ITEMS

SAFETY AND IMPORTANT WARNING ITEMS

Read carefully the Safety and Important Warning Items described below to understand them before doing ser­vice work.

IMPORTANT NOTICE

Because of possible hazards to an inexperienced person servicing this copier as well as the risk of damage to
the copier, Minolta Corporation s tron gly re comm ends that all se rvicing be performed only by Minolta-trained ser­vice technicians.
Changes may have been made to this copier to improve its performance after this Service Manual was printed.
Accordingly, Minolta Corporation does not warrant, either explicitly or implicitly, that the information contained in
this Service Manual is complete and accurate.
The user of this Service Manual must assume all risks of personal injury and/or damage to the copier while ser­vicing the copier for which this Service Manual is intended.
Therefore, this Service Manual must be carefully read before doing service work both in the course of technical
training and even after that, for performing maintenance and control of the copier properly.
Keep this Service Manual also for future service.

DANGER, WARNING, AND CAUTION SYMBOLS AND
EXPRESSIONS

In this Service Manual, each of three expressions " DANGER," " WARNING," and " CAUTION" is defined
as follows together with a symbol mark to be used in a limited meaning.
When servicing the copier, the relevant works (disassembling, reassembling, adjustment, repair, maintenance,
etc.) need to be conducted with utmost care.

DANGER :Action having a high possibility of suffering death or serious injury
WARNING:Action having a possibility of suffering death or serious injury
CAUTION :Action having a possibility of suffering a slight wound, medium trouble, and property

damage

Symbols used for important warning items are defined as follows:

:Precaution

:Prohibition

:Direction

General precaution Electric shock Heated surface

General prohibition Do not touch with wet hand Do not disassemble

General instruction Unplug Ground/Earth

S-1

SAFETY AND IMPORTANT WARNING ITEMS

SAFETY WARNING S

[1] MODIFICATIONS NOT AUTHORIZED BY MINOLTA

Minolta copiers are renowned for their high reliability. This reliability is achieved through high-quality design and
a solid service network.
Copier design is a highly complicated and delicate process where numerous mechanical, physical, and electrical
aspects have to be taken into consideration, with the aim of arriving at proper tolerances and safety factors. For
this reason, unauthorized modifications involve a high risk of degradation in performance and safety. Such mod­ifications are therefore strictly prohibited. the points listed below are not exhaustive, but they illustrate the rea­soning behind this policy.

PROHIBITED ACTIONS:

• Using any cables or power cord not specified by Minolta.

• Using any fuse or thermostat not specified by Minolta. Safety will not be
assured, leading to a risk of fire and injury.

• Disabling fuse functions or bridging fuse terminals with wire, metal clips, sol­der or similar object.

• Disabling relay functions (such as wedging paper between relay contacts)

• Disabling safety functions (interlocks, safety circuits, etc.) Safety will not be
assured, leading to a risk of fire and injury.

• Making any modification to the copier unless instructed by Minolta

• Using parts not specified by Minolta

S-2

SAFETY AND IMPORT ANT WARNING ITEMS

[2] CHECKPOINTS WHEN PERFORMING ON-SITE SERVICE

Minolta copiers are extensively tested before shipping, to ensure that all applicable safety standards are met, in
order to protect the customer and customer engineer (hereaf ter called the CE) from the risk of injury. However, in
daily use, any electrical equipment may be subject to parts wear and eventual failure. In order to maintain safety
and reliability , the CE must perform regular safety checks.

1.Power Supply

WARNING: Wall Outlet

• Check that mains voltage is as specified. Plug the power cord into the dedi­cated wall outlet with a capacity greater than the maximum power consump­tion.

If excessive current flows in the wall outlet, fire may result.

• If two or more power cords can be plugged into the wall outlet, the total load
must not exceed the rating of the wall outlet.

If excessive current flows in the wall outlet, fire may result.

kw

WARNING: Power Plug and Cord

• Make sure the power cord is plugged in the wall outlet securely.

Contact problems may lead to increased resistance, overheating, and the
risk of fire .

• Check whether the power cord is damaged. Check whether the sheath is
damaged.

If the power plug, cord, or sheath is damaged, replace with a new power
cord (with plugs on both ends) specified by Minolta. Using the damaged
power cord may result in fire or electric shock.

• When using the power cord (inlet type) that came with this copier, be sure to
observe the following precautions:
a. Make sure the copier-side power plug is securely inserted in the socket

on the rear panel of the copier.
Secure the cord with a fixture properly.

b. If the power cord or sheath is damaged, replace with a new power cord

(with plugs on both ends) specified by Minolta.
If the power cord (inlet type) is not connected to the copier securely, a
contact problem may lead to increased resistance, overheating, and risk
of fire.

• Check whether the power cord is not stepped on or pinched by a table and
so on.

Overheating may occur there, leading to a risk of fire.

S-3

SAFETY AND IMPORTANT WARNING ITEMS

WARNING: Power Plug and Cord

• Do not bundle or tie the power cord.
Overheating may occur there , leading to a risk of fire.

• Check whether dust is collected around the power plug and wall outlet.
Using the power plug and wall outlet without removing dust may result in
fire.

• Do not insert the power plug into the wall outlet with a wet hand.
The risk of electric shock exists.

• When unplugging the power cord, grasp the plug, not the cable.
The cable may be broken, leading to a risk of fire and electric shock.

WARNING: Wiring

• Never use multi-plug adapters to plug multiple power cords in the same out-

let.

If used, the risk of fire exists.

• When an extension cord is required, use a specified one.
Current that can flow in the extension cord is limited, so using a too long
extension cord may result in fire.
Do not use an extension cable reel with the cable taken up. Fire may
result.

WARNING: Ground Lead

• Check whether the copier is grounded properly.
If current leakage occurs in an ungrounded copier, you may suffer electric
shock while operating the copier. Connect the ground lead to one of the
following points:
a. Ground terminal of wall outlet
b. Ground terminal for which Class D work has been done

S-4

SAFETY AND IMPORTANT WARNING ITEMS

WARNING: Ground Lead

• Pay attention to the point to which the ground lead is connected.

Connecting the ground lead to an improper point such as the points listed

below results in a risk of explosion and electric shock:

a. Gas pipe (A risk of explosion or fire exists.)

b. Lightning rod (A risk of electric shock or fire exists.)

c. Telephone line ground (A risk of electric shock or fire exists in the case

of lightning.)

d. Water pipe or faucet (It may include a plastic portion.)

2.Installation Requirements

WARNING: Prohibited Installation Place

• Do not place the copier near flammable materials such as curtains or volatile

materials that may catch fire.

A risk of fire exists.

• Do not place the copier in a place exposed to water such as rain water.

A risk of fire and electric shock exists.

WARNING: Nonoperational Handling

• When the copier is not used over an extended period of time (holidays, etc.),

switch it off and unplug the power cord.

Dust collected around the power plug and outlet may cause fire.

CAUTION: Temperature and Humidity

• Do not place the copier in a place exposed to direct sunlight or near a heat

source such as a heater.

A risk of degradation in copier performance or deformation exists.

Do not place the copier in a place exposed to cool wind.

Recommended temperature and humidity are as follows:

Temperature: 10

Humidity: 10% to 80% (no dew condensation)

Avoid other environments as much as possible.

°C to 30°C 50 °F to 86°F

CAUTION: Ventilation

• Do not place the copier in a place where there is much dust, cigarette smoke,

or ammonia gas.

Place the copier in a well ventilated place to prevent machine problems

and image faults.

S-5

SAFETY AND IMPORTANT WARNING ITEMS

CAUTION: Ventilation

• The copier generates ozone gas during operation, but it is not sufficient to b e

harmful to the human body.

If a bad smell of ozone is present in the f ollowing c ases , ve ntilate t he room.
a. When the copier is used in a poorly ventilated room
b. When taking a lot of copies
c. When using multiple copiers at the same time

CAUTION: Vibration

• When installing the copier, read the Installation Guide thoroughly. Be sure to

install the copier in a level and sturdy place.

Constant vibration will cause problems.

• Be sure to lock the caster stoppers.
In the case of an earthquake and so on, the copier may slide, leading to a
injury.

CAUTION: Inspection before Servicing

• Before conducting an inspection, read all relevant documentation (Service

Manual, technical notices, etc.) and proceed with the in spec tion following the
prescribed procedure, using only the prescribed tools. Do not make any
adjustment not described in the documentation.

If the prescribed procedure or tool is not used, the copier may break and a
risk of injury or fire exists.

• Before conducting an inspection, be su re to disconnect the power plugs from

the copier and options.

When the power plug is inserted in the wall outlet, some units are still pow­ered even if the POWER switch is turned OFF. A risk of electric shock
exists.

• The area around the fixing unit is hot.
Yo u may get burnt.

DANGER: Work Performed with the Copier Powered

• Take every care when making adjustments or performing an operation check

with the copier powered.

If you make adjustments or perform an operation check with the external
cover detached, you may touch live or high-voltage parts or you may be
caught in moving gears or the timing belt, leading to a risk of injury.

S-6

SAFETY AND IMPORT ANT WARNING ITEMS

DANGER: Work Performed with the Copier Powered

• Take every care when servicing with the external cover detached.
High-voltage exists around the drum unit. A risk of electric shock exists.

WARNING: Safety Checkpoints

• Check the exterior and frame for edges, burrs, and other damages.
Personal injuries may result.

• Do not allow any metal parts such as clips, staples, and screw s to f all into the

copier.

They can short internal circuits and cause electric shock or fire.

• Check wiring for squeezing and any other dam age.
Current can leak, leading to a risk of electric shock or fire.

• When disconnecting connectors, grasp the connector, not the cable.
(Specifically, connectors of the AC line and high-voltage parts)
Current can leak, leading to a risk of electric shock or fire.

• Carefully remove all toner remnants and dust from electrical parts and elec-

trode units such as a charging corona unit.

Current can leak, leading to a risk of copier trouble or fire.

• Check high-voltage cables and sheaths for any damage.
Current can leak, leading to a risk of electric shock or fire.

• Check electrode units such as a charging corona unit for deterioration and

sign of leakage.

Current can leak, leading to a risk of trouble or fire.

• Before disassembling or adjusting the write unit incorporating a laser, make

sure that the power cord has been disconnected.

The laser light can enter your eye, leading to a risk of loss of eyes ight.

• Do not remove the cover of the write unit. Do not supply power with the write

unit shifted from the specified mounting position.

The laser light can enter your eye, leading to a risk of loss of eyes ight.

• When replacing a lithium battery, replace it with a new lithium battery speci-

fied in the Parts Guide Manual. Dis pose of the used lithium battery using the
method specified by local authority.

Improper replacement can cause explosion.

S-7

SAFETY AND IMPORTANT WARNING ITEMS

WARNING: Safety Checkpoints

• After replacing a part to which AC voltage is applied (e.g., optical lamp and
fixing lamp), be sure to check the installation state.

A risk of fire exi sts.

• Check the interlock switch and actuator for loosening and check whether the
interlock functions properly.

If the interlock does not function, you may receive an electric shock or be
injured when you insert your hand in the copier (e.g., for clearing paper
jam).

• Make sure the wiring cannot come into contact with sharp edges, burrs, or
other pointed parts.

Current can leak, leading to a risk of electric shock or fire.

• Make sure that all screws, components, wiring, connectors, etc. that were
removed for safety check and maintenance have been reinstalled in the orig­inal location. (Pay special attention to forgotten connectors, pinched cables,
forgotten screws , etc.)

A risk of copier trouble, electric shock, and fire exists.

HANDLING OF MATERIALS FOR SERVICING

• Unplug the power cord from the wall outlet.

Drum cleaner (isopropyl alcohol) and roller cleaner (acetone-based) are
highly flammable and must be handled with care. A risk of fire exists.

• Do not replace the cover or turn the copier ON before any solvent remnants
on the cleaned parts have fully evaporated.

A risk of fire exi sts.

• Use only a small amount of cleaner at a time and take care not to spill any
liquid. If this happens, immediately wipe it off.

A risk of fire exi sts.

• When using any solvent, ventilate the room well.

Breathing large quantities of organic solvents can lead to discomfort.

S-8

SAFETY INFORMATION

DANGER: HANDLING OF MATERIALS FOR SERVICING

• Toner and developer are not harmful substances, but care must be taken not
to breathe excessive amounts or let the substances come into contact with
eyes, etc. It may be stimulative .

If the substances get in the eye, rinse with plenty of water immediately.
When symptoms are noticeable, consult a physician.

• Never throw the used cartridge and toner into fire.

You may be burned due to dust explosion.

[3] CONCLUSION

1. Safety of users and customer engineers depends highly on accurate maintenance and administration.

Therefore, safety can be maintained by the appropriate daily service work conducted by the customer
engineer.

2. When performing service, each copier on the site must be tested for safety. The customer engineer must

verify the safety of parts and ensure appropriate management of the equipment.

SAFETY INFORMATION

IMPORTANT INFORMATION

The Center for Devices and Radiological Health (CDRH) of the U.S. Food and Drug Administration implemented
regulations for laser products manufactured since August 1, 1976. Compliance is mandatory for products mar­keted in the United States.

This copier is certified as a “Class 1” laser product under the U.S.
Department of Health and Human Services (DHHS) R adiat ion Performance Standard according to the Radiation
Control for Health and Safety Act of 1968. Since radiatio n emitt ed ins i de t his c opier is completely confined within
protective housings and ex ter nal covers, the laser beam cannot escape during any phase of normal user opera­tion.

S-9

SAFETY INFORMATION

SAFETY CIRCUITS

This machine is provided with the following safety cir­cuits to prevent machine faults from resulting in seri­ous accidents.

[1] Overall protection circuit
[2] L2 and L4 (fixing heater lamps) overheating

prevention circuit

These safety circuits are described below to provide
the service engineer with a renewed awareness of
them in order to prevent servicing errors that may
impair their functions.

[1] Overall Protection Circuit

CBR1

NF NF2

1. Protection by CBR1 and CBR2 (circuit
breakers)

CBR1 interrupt the AC line instantaneously
when an excessive c urrent flows due to a short
in the AC line.

CAUTION:
The CBR1 and CBR2 functions must not
be deactivated under any circumstances.

[2] Protection by L2 and L4 (fixi ng heater

lamps) overheating prevention circuit

ACDB

RL
driver
section

AC
driver
section

TH4

TH3

TH2

TH1

CB

Control
section

1. Protection by software

The output voltage from TH1 (fixing tempera­ture sensor 1) is read by the CPU. If this volt­age is abnormal, L2 (fixing heater lamp 1), and
L4 (fixing heater lamp 3), and RL1 (main relay)
are turned OFF.

CAUTION:
Do not change the gap between the roller
and TH1. When repl-acing TH1, check the
specified mounting dimensions.
The RL1 function must not be deactivated
under any circum-stances.

RL1

RL1

TS1

L2

L4

S-10

2. Protection by the hardware circuit

The output voltages from TH1 and TH2 (fixing
temperature sensor 2), TH3 (fixing tempera­ture sensor 3), and TH4 (fixing temperature
sensor 4) are compared with the abnormality
judgement reference value in the comparator
circuit. If the output voltage from TH1, TH2,
TH3, or TH4 exceeds the reference value, L2,
L4, and RL1 are turned off in hardware means.

CAUTION:
Periodically check t he TH2 and TH4 face s
contacting the roller, and replace TH2
and/or TH4 if any abnormality is detected.
Do not change the gap between the roller
and each sensor TH2 and TH4. When
replacing TH2 or TH4, check the specified
mounting dimensions.
The RL1 function must not be deactivated
under any circum-stances.

3. Protection by TS1 (thermostat (upper)) and
TS2 (thermostat (lower))

TS1 is turned off when the temperature of the
fixing roller (upper) exceeds the specified
value, and TS2 is turned off when the tempera­ture of the heating (upper) roller exceeds the
specified value, thus interrupting the power to
L2 and L4 directly .

CAUTION:
Do not use any other electrical conductor
in place of TS1 and TS2.

SAFETY INFORMATION

S-11

SAFETY INFORMATION

INDICATION OF WARNING ON THE MACHINE

Caution labels shown below are attached in some areas on/in the machine areas.
When accessing these areas for maintenance, repair, or adjustment, special care should be taken to avoid burns
and shock hazards.

CAUTION

CAUTION
ATTENTION
VORSICHT
PRECAUCION
ATTENZIONE

2

2

1

(Top surface of
the fixing unit)

(Inside of
the fixing unit)
(Front side of
the fixing unit)

ATTENTION

VORSICHT

PRECAUCION

(Both sides of the fixing unit)

CAUTION

The fixing unit is very hot.
To avoid getting burned DO NOT
TOUCH.

ATTENZIONE

WARNING
DANGER
WARNUNG
ADVERTENCIA
AVVERTIMENTO

WARNING

This area generates
high voltage. If
touched, electrical
shock may occur. DO
NOT TOUCH!

CAUTION
ATTENTION
VORSICHT

CAUTION

The conveyance fixing unit is heavy.
Use care and draw it out gently;
otherwise you may be injured.

PRECAUCION
ATTENZIONE

CAUTION

DO NOT put your hand between the
main body and developing fixing
unit; otherwise you may be injured.

CAUTION

Please adhere to all caution labels to avoid burns or injury.

S-12

CAUTION
ATTENTION
VORSICHT
PRECAUCION
ATTENZIONE

SAFETY INFORMATION

DANGER

VISIBLE LASER RADIATION WHEN OPEN.
AVOID DIRECT EXPOSURE TO BEAM.

Unplug the machine before removing platen glass.

WARNING

Debrancher le copieur avant de retirer la vitre d'exposition.

DANGER

Vor Entfernen des Vorlagenglases Netzstecker ziehen.

WARNUNG

Desenchufe la maquina antes de quitar el vidrio.

ADVERTENCIA

Estrarre la spina dalla presa prima di rimuovere il vetro di esposizione.

AVVERTIMENTO

PS

Elektrische T eile
In dieser Einheit

PS

PS

for BA standard

VISIBLE LASER RADIATION WHEN OPEN.
AVOID DIRECT EXPOSURE TO BEAM

LASERSTRAHLUNG,WENN ABDECKUNG
GEÖFFNET.
NICHT DEM STRAHL AUSSETZEN.

CAUTION

Please adhere to all caution labels to avoid burns or injury.

S-13

RAYON LASER VISIBLE LORS DE
L‘OUVERTURE.
EVITER L‘EXPOSITION DERECTE.

PS

SAFETY INFORMATION

Tray 3

FN-7 Only

CAUTION
ATTENTION
PRECAUCION
CUIDADO
CAUTION
ATTENTION
VORSICHT
PRECAUCION
ATTENZIONE

Tray 1

CAUTION

Tray 2

CAUTION

DO NOT put your hand
between the main body
and tray; otherwise you
may be injured.

CAUTION

Use care after opening the
paper exit outlet. DO NOT
put your hands into the
paper exit outlet as you
may be injured.

CAUTION

Inside the lower paper exit outlet
is the roller drive unit.
DO NOT put your hands into the
paper exit outlet as you may be
injured

CAUTION

Please adhere to all caution labels to avoid burns or injury.

Finisher [FN-7 / FN-115]

S-14

WARNING

WARNING

Unplug the machine before removing
panels.

D brancher lÕappareil avant de
retirer les panneaux arri res.

Desenchufe la m‡quina antes de
quitar los paneles.

Desconecte a unidade da tomada
antes de remover os pain is.

Unplug the machine before removing
panels.

D brancher lÕappareil avant de
retirer les panneaux arri res.

Vor Abnahme der Schutzverkleidung
Netzstecker ziehen.

Desenchufe la m‡quina antes de
quitar los paneles.
Scollegare la macchina prima di
rimuovere i pannelli.

SAFETY INFORMATION

CAUTION

Trimmer [TMG-2]

CAUTION

Please adhere to all caution labels to avoid burns or injury.

S-15

SAFETY INFORMATION

WARNING

Unplug the machine before removing
panels.

Débrancher l’appareil avant de retirer
les panneaux arrières.

Desenchufe la máquina antes de
quitar los paneles.

Desconecte a unidade da tomada
antes de remover os painéis.

Unplug the machine before removing
panels.

Débrancher l’appareil avant de retirer
les panneaux arrières.

Vor Abnahme der Schutzverkleidung
Netzstecker ziehen.

Desenchufe la máquina antes de
quitar los paneles.
Scollegare la macchina prima di
rimuovere i pannelli.

<PK-3 Puncher>
<ZK-2 Puncher with Z-folding>

CAUTION

Please adhere to all caution labels to avoid burns or injury.

S-16

1

OUTLINE

1 OUTLINE

1 OUTLINE

OUTLINE OF SYSTEM

OUTLINE

Cover Inserter

[Cover In serter C]

Trimmer
[TMG-2]

Finisher

[FN-115]

Finisher

[FN-7]

Puncher

[PK-3]

Puncher with

Z-folding

[ZK-2]

Paper

exit tray

Printer Controller

Expansion memory unit

[M64-1 / M128-1]

1 OUTLINE

LCT [C-403]

LCT [C-404]

1-1

OUTLINE

PRODUCT SPECIFICATIONS

[1] Type

1 OUTLINE

[2] Functions

Installation Type:

Copying method:

Document tray type:

Photosensitive material:

Sensitizing method:

Paper feed trays:

Applicable document types:

Document size:

Copy paper size:

• Metric area
A3 to A5, 11x17 to 8.5 x11, F4

• Inch Area
11x17 to 8.5 x5.5, A3 to B5R, F4
Wide paper (max. 314x445mm)*2
*2: When using C404

Paper size for ADU paper passage:

Max. 314 x 459 mm to A5 or

8.5 x 5.5 min.

Magnifications
Fixed magnifications:

• Metric area
x1.00, x2.00, x1.41, x1.22, x1.15,
x0.86, x0.82, x0.71, x0.50

• Inch Area
x1.00, x4.00, x2.00, x1.55, x1.29,
x0.77, x0.65, x0.50

Special ratio magnifications:

Console type (floor-mounted type)

Indirect electrostatic method

Fixed

OPC

Laser writing

Three stacked trays (two for 500
sheets of 80 g/m
one for 1000 sheets of 80 g/m

20lbs. paper)
A by-pass tray for various paper

sizes (150 sheets of 80 g/m
lbs. paper)

LCT (4000 sheets of 80 g/m
lbs. paper)*1
*1: Optional

Sheets, book, solid object

A3 (11x17) max.

3 modes

2

or 20lbs. paper;

2

or 20

2

or 20

Zoom magnifications:

Vertical magnifications:

Horizontal magnifications:

Warm-up time:

First copy out time:

2

or

Continuous copy speed (life size, copies/
min):

Continuous copy count:

Copy density selections:

E-RDH memory capacity:

x0.25 to x4.00 (600 dpi, in 1% steps)

x0.25 to x4.00 (600 dpi, in 1% steps)

x0.25 to x4.00 (600 dpi, in 1% steps)

Less than 6 minutes*2
*2: 6 minutes is the machine for the

230VAC specification.
Warm-up time differs depending
on the Power sour ce (voltage).

Mode A4, 8.5x11

Manual 3.3 seconds or less

*Straight paper ejection with the
copied image facing up, platen
mode, life size, paper f eed from tra y
1

Size cpm

A4, 8.5x11 85

1 to 9999

AE, manual
Arbitrary density (2 modes)

standard 128 MB
maximum 512 MB

1-2

OUTLINE

[3] Applicable Copy Paper

Plain paper:

High quality paper 60 to 90 g/m

Special paper:

Bypass feed only:

Tray feed only:

ADU paper passage:

or 17 to 24 lbs

High quality paper
50 to 59 g/m

13 to 16 lbs, 24 to 40 Ibs

Label paper
OHP Film
Blueprint master paper

High quality paper
171 to 200 g/m

High quality paper
60 to 200 g/m

2

, 91 to 170 g/m2 or

2

[4] Options

LCT: C-403 / C-404
Expansion memory unit:

Finisher: FN-115 / FN-7
Post inserter: Cover Inserter C
Trimmer: TMG-2
Puncher: PK-3
Puncher with Z-folding :ZK-2
Paper exit tr ay
Printer Controller:

M64-1: 64MB
M128-1: 128MB

2

or 40 to 45 lbs

or 17 to 45 lbs

[5] Particulars of Machine

2

Power supply:

230 VAC EURO: -14 to 10.6 %
USA : ±10 %
50 Hz/ 60 Hz
208 to 240 VAC 60 Hz

Power consumption:

230 V Machine: 3450 W max.
(Full option)
208 to 240 V Machine: 3840 W max.
(Full option)

Weight: Approx. 280 kg (617 lbs.)
Machine dimensions:

35"

[6] Maintenance and Life

Periodic maintenance:

Machine life:

Every 500,000 copies

30,000,000 copies or 5 years

[7] Consumables

Developer: Exclusively for Minolta Di850
Toner : Exclusively for Minolta Di850
Drum: Exclusively for Minolta Di850 (ø100)

[8] Environmental Conditions

Temperature:

Humidity: 10% to 80% RH
Note: The information herein may subject to

10°C to 30°C (50°F to 86°F)

change for improvement without notice.

1 OUTLINE

45.5"

35.5"

1-3

OUTLINE

CENTER CROSS-SECTIONAL VIEW

1 OUTLINE

Image processing
section

Exposure lamp

Fixing
section

Paper exit
section

Paper reverse/
exit section

Cleaning section PCL

Charging corona
section

RADF

Image read
section

Image write
section

Developing
section

Second paper
feed section

By-pass tray
T ransf er corona

section
Vertical conveyance

section
TSL

Tray 1

Tray 2

section

Separation
corona section

1-4

Tray 3

ADUPaper conveyance

DRIVE SYSTEM DIAGRAM

OUTLINE

[1] Main Drive Sect io n

To paper conveyance and
transfer/separation cor ona
cleaning section

Fixing unit
Heating roller

1

Fixing unit
upper roller

1 OUTLINE

FRONT

Main motor (M1)

Fixing unit lower roller

1-5

OUTLINE

[2] Drum Drive Se ct io n

1 OUTLINE

Drum motor (M2)

Separation claw
solenoid (SD4)

Toner guide brush

Drum

FRONT

Toner guide shaft

Toner conveyance screws

Separation claw unit

Separation claw swing cam

1-6

OUTLINE

[3] Developing Drive Section

Agitator screw

Developing motor ( M3)

[4] Paper Feed Drive Section

5

FRONT

Agitator wheel

Developing slee ve

To tray 1 paper feed/ tray up drive section

2

FRONT

1 OUTLINE

6

To vertical conveyance section

To vertical conveyance section

Paper feed motor (M4)

To tray 2 paper feed/ tray up drive section

3

To tray 3 paper feed/tray up drive section

4

1-7

OUTLINE

[5] Tray 1 and 2 Paper Feed Drive Section

1 OUTLINE

Pre-feed registration roller

Pre-registration MC1/2
(MC4/MC6)

Tray up motor 1/2 (M19/M20)

FRONT

Feed roller

2
3

From paper feed
drive section

Feed MC1/2 (MC3/MC5)

Paper feed roller

Double feed
prevention roller

1-8

OUTLINE

[6] Tray 3 Paper Feed Drive Section

Pre-feed registration roller

Pre-registration MC3
(MC8)

1 OUTLINE

Feed roller

FRONT

4

From paper feed drive
section

Tray up motor 3 (M21)

Paper feed roller

Double feed
prevention roller

Feed MC3 (MC7)

1-9

OUTLINE

[7] Vertical Conveyance Drive Section

1 OUTLINE

From bypass
paper feed drive

7

section

FRONT

Vertical conveyance
roller (Upper)

Vertical
conveyance
MC1 (MC9)

Vertical
conveyance
MC2 (MC10)

From paper
feed drive

5

section

From paper
feed drive

6

section

Vertical conveyance
roller (Middle)

Vertical conveyance
roller (Lowe r )

1-10

OUTLINE

[8] By-pass Paper Feed Drive Section

Tray up/down motor (by-pass tray: M22)

Paper feed roller

To ADU conveyance

8

drive section

1 OUTLINE

FRONT

Feed roller

Loop roller motor (M6)

To vertical conveyance

7

1-11

OUTLINE

[9] Conveyance/Transfer and Separation Wire Cle aning Drive Section

1 OUTLINE

Transfer/separation cleaning motor (M18)

Thick paper conveyance rollers

1

1-12

From main drive section

FRONT

Conveyance belts

OUTLINE

[10] ADU Conveyance Drive Sect ion

Registration MC (MC1)

Loop roller

Registration roller

ADU exit roller

8

From by-pass
paper feed
drive section

Registration mo to r
(M12)

ADU pre-registration
MC (MC2)

Transfer motor (M9)

FRONT

1 OUTLINE

ADU conveyance motor (M8)

ADU reverse roller

ADU reverse motor (M7)

Paper reverse/exit
motor (M5)

Pre-registration roller

Pre-transfer roller

Pre-registration loop
roller

ADU horizontal
conveyance roller 2

ADU horizontal
conveyance roller 1

From fixing
unit drive

1-13

Paper rev erse/exit
entrance roller

Paper reverse/
exit roller 1

Paper reverse/
exit roller 2

Paper reverse/exit roller 3

OUTLINE

[11] Paper Exit Drive Section

1 OUTLINE

Paper exit motor (M10)

[12] Toner Supply Drive Section

Toner supply motor 1 (M11)

FRONT

Paper exit roller

Toner supply motor 2 (M15)

FRONT

Toner car t ridge

1-14

OUTLINE

[13] Optic s Drive Se ction

Slit-glass

1 OUTLINE

Scanner drive motor (M13)

First mirror

Second mirror

Third mirror

Optics wire (Rear)

FRONT

Optics wire (Front)

1-15

OUTLINE

[14] Web Drive Section

1 OUTLINE

Web drive motor (M16)

FRONT

Cleaning web

1-16

2

UNIT EXPLANATION

2 UNIT EXPLANATION

2 UNIT EXPLANATION

EXTERNAL SECTION

[1] Composition

EXTERNAL SECTIO N

Main switch

Left side cover

Left front door

Operation panel

Front right door

Bypass tray

Tray 1
Tray 2

Tray 3

Right side cover
(middle)

Right side cover
(upper)

Ver tical
Conveyance
door

RADF(EDH-5)

Cooling
cover

2 UNIT EXPLANATION

Optional cover

Rear cover

Right side cover
(lower)

2-A-1

2 UNIT EXPLANATION

DRIVE SECTION

[1] Composition

DRIVE SECTION

Drum motor (M2)

Main motor (M1)

Developing motor (M3)

Loop roller motor (M6)

Paper feed motor (M4)

Paper exit motor
(M10)

[2] Mechanisms

Mechanism Driven Parts Method

*1 Drum drive Drum, clearer fur brush Gear drive (dedicated motor)

*1 Developing drive Developing sleeve Gear drive (dedicated motor)

*1 Main drive Fixing upper roller Gear drive (dedicated motor)

*1 Paper feed drive Tray 1/2/3, Vertical conveyance roller

(middle/lower)

*1 By-pass/loop drive By-pass feed roller, loop roller, vertical

conveyance roller (upper)

*1 Paper exit drive Paper exit roller Gear drive (dedicated motor)

*1 Independent drive mechanisms

Drive mechanisms are driven by dedicated motors to ensure high-speed operation and to improve service­ability of the drum unit and developing performance.
In order to improve the fixativeness in copying thick paper, the selection of [Thick paper 3] in the key operation
mode decreases the linear speed of the main motor (M1) to 210mm/s only when the paper passes through
the fixing unit.
The mode of [Thick paper 3] is available only when the length of the paper in the paper feed direction is 216mm
or shorter and the paper is fed from LT.

Gear drive (dedicated motor) + Belt

Gear drive (dedicated motor)

2 UNIT EXPLANATION

2-B-1

DRIVE SECTION

[3] M1 (Main) Control

MS2 MS1

24VDC

PGND

DCPS2

M1 CONT

M1 EM

CLK

PRCB

2 UNIT EXPLANATION

M1 (main) is controlled by the PRCB (printer control
board) and the motor drive power is supplied from
DCPS2 (DC power supply unit 2).

1. Operation

M1 is a motor driven by 24V DC. It drives fixing
upper and lower rollers, paper con vey ance belts,
and thick paper conveyance roller. M1 incorpo­rates a speed controller circuit to send a signal
indicating abnormal rotation to PRCB when the
PLL lock has been released for longer than the
specified period of time.
M1 starts rotating when the START PRINT but­ton is pressed and stops when the last copied
paper has been ejected. During the warm-up
operation, M1 rotates to rotate the fixing rollers.
When either one of the front doors of this
machine opens or closes, MS1 (interlock 1) or
MS2 (interlock 2) actuates to stop supplying the
DC power to the motor, causing the M1 to stop.

2. Signals

a. Input signal

(1) M1 EM (M1 to PRCB)

M1 fault detection signal.
[H]:Abnormal rotation (PLL lock has been

released for 2 to 3 seconds or longer.)

[L]: Normal rotation

b. Output signal

(1) M1 CONT (PRCB to M1)

M1 drive control signal.
[H]:M1 ON
[L]: M1 OFF

(2) CLK (PRCB to M1)

Clock signal for M1.

[4] M2 (Dru m) Control

24VDC

PGND

DCPS2

M1

M2CONT

PRCB

M2 F/R

SGND

M2 EN

M2 (drum) is controlled by the PRCB (printer control
board) and the motor drive power is supplied from
DCPS2 (DC power supply unit 2).

1. Operation

M2 is a motor driven by 24V DC. It drives a drum,
toner guide brush, toner guide shaft, toner con­veyance screw, and separation claw swing sec­tions. M2 incorporates a speed sensor (encoder)
to send a feedback signal to PRCB. Using this
signal, PRCB detects the rotational speed and
calculates the PWM duty to be given to the
motor, controlling the M2 speed. In addition to
the speed sensor, M2 also has a fly wheel mech­anism to ensure accurate and steady rotation.
M2 starts rotating when the STA RT PRINT but­ton is pressed and stops when the last copied
paper has been ejected.
When either one of the front doors of this
machine opens or closes, MS2 (interlock 1) or
MS2 (interlock 2) actuates to stop supplying the
DC power to the motor, causing the M2 to stop.

2. Signals

a. Input signal

(1) M2 EN (M2 to PRCB)

M2 motor encoder signal.

b. Output signals

(1) M2 CONT (PRCB to M2)

M2 drive control signal (PCOM).
[L]: M2 ON
[H]:M2 OFF

(2) M2 F/R (PRC B to M 4 )

M2 rotational direction switchover signal.
[H]:CCW (relative to motor shaft)
[L]: CW (relative to motor shaft)

MS2 MS1

M2

2-B-2

READ SECTION

[1] Composition

READ SECTION

Optics rail (R)

Scanner drive wire

Slit glass

Scanner cooling fan (FM7)

A/D converter
board

Exposure unit

CCD unit

[2] Mechanisms

Mechanism Method

Light source Xenon lamp
Exposure Light source shift slit exposure, static exposure
Scanning Platen original scanning: 1st, 2nd, and 3rd mirrors are shifted.

Lamp power supply Lamp cord
Optics cooling Cooling fan

RADF original scanning: Original is moved with light source held stationary.

V-mirror unit
(2nd and 3rd mirrors)

2 UNIT EXPLANATION

2-C-1

READ SECTION

[3] M13 (Scanner Drive) Control

M13 CLK

M13 F/R

M13 CSEL

M13 V0
M13 V1
M13 V2

PS5
PS7
PS6
PS4

2 UNIT EXPLANATION

PRCB SCDB DCPS1

M13 (scanner drive) is driven by the SCDB (scanner
drive board) and is controlled by the PRCB (printer
control board).
Related signals are PS5 (scanner HP), PS6 (original
HP), and PS7 (ADF brake).

1. Operation

a. Operation of M13

M13 is a 3-phase stepping motor driven using
the 3-phase bipolar constant-current drive
method. The motor is turned ON/OFF by supply­ing/stopping clock pulses.

b. Movement speed of the exposure unit

Scanning speed

Operation mode Movement speed

Scan 400 mm/sec (600 dpi, 1:1)
Forward 615.38 mm/sec
Home position

search

c. Positions of sensors

Paper exit side Paper feed side

M13 DRIVE U
M13 DRIVE V

M13 DRIVE W

5VDC

SGND

5VDC

SGND

205.1 mm/sec

PS5

PS7

PS6

M13

PS5

PS7

PS6

24VDC
PGND

DCPS2

5VDC
SGND

d. Exposure unit home position search

If the exposure unit is not at the home position
when the main switch is turned ON or when the
ST AR T PRINT button is pressed, the home posi­tion is searched for in the followin g manner:

(1) When the ex posure unit is on the paper e xit side

with respect to the home position
When the exposure unit is at PS7 (ADF brake)
(PS7 is ON), it moves forward at a low speed.
And it moves until PS5 (scanner HP) turns ON
and OFF again, then stops. It moves backward
until PS5 turns ON again.
When the exposure unit is between PS7 and
PS5, it moves backward until PS7 turns ON
before moving f orward as mentioned above.

(2) When the expos ure unit is on the paper feed side

When the exposure unit is at PS5 (PS5 is ON), it
moves forward at a low speed until PS5 turns
OFF before moving as discussed in (1) above.
When the exposure unit is located on the paper
feed side with respect to PS5, it mov es backward
then stops for a short while after PS5 turns ON.
Then it moves forward and performs operations
as described in (1) above.

e. Read with shading correction

L1 is turned ON, when black correcti on has been
completed after the home position search oper­ation, thus reading the light reflected by the white
reference plate installed underneath the glass
stopper plate and performing the first white cor­rection. Then, the exposure unit moves to the
paper exit side, performs the second white cor­rection while stopping at the preset position, then
returns to the home position to turn OFF L1.

ADF
break

PS7 PS5

Scanner
HP

First white correction
Second white correction

PS7 PS5 PS6

2-C-2

READ SECTION

f. ADF copy operation

Scanner
HP

Second white correction
First white correction

Original
read
position

ADF
break

PS7 PS5

g. Platen copy operation

Scanner

ADF
brake

HP

PS5 PS6PS7

Second white correction
First white correction

AE scan
Original area justment

Exposure scan

Home position search

Original HP

2. Signals

a. PRCB input signals

(1) PS5 (PS5 to SCDB to PRCB)

Scanner home position detection signal.
The reference position for the home position of
the exposure unit is detected.
[L]: The exposure unit is detected.
[H]:The exposure unit is not detected.

(2) PS6 (PS6 to SCDB to PRCB)

Original home position detection signal.
In the platen mode, the ref erence position f or the
original’s leading edge is detected.
[L]: The exposure unit is detected.
[H]:The exposure unit is not detected.

(3) PS7 (PS7 to SCDB to PRCB)

ADF brake detection signal.
In the DF mode, the exposure ref erence position
is detected.
[L]: The exposure unit is detected.
[H]:The exposure unit is not detected.

Scanner
return

b. PRCB output signals

(1) M13 CLK (PRCB to SCDB)

Clock signal for M13.

(2) M13 F/R (PRCB to SCDB )

M13 rotational direction switchover signal.
[L]: The exposure unit is moved t oward the paper

exit side.

[H]:The exposure unit is mov ed toward the paper

feed side.

(3) M13 CSEL (PRCB to SC DB)

M13 excitation switchover signal.
[L]: 2-/3-phase excitation
[H]:W2-/3-phase excitation

(4) M13 V0 to V2 (PRCB to SCDB)

M13 excitation current swit chover signal.

c. SCDB output signals

(1) M13 DRIVE, U, V, W (SCD B to M13)

M13 drive control signals.
These signals are used to control rotation of
M13. By supplying and stopping clock pulses,
the motor is turned ON/OFF and the rotational
direction is switched.

2 UNIT EXPLANATION

2-C-3

READ SECTION

[4] Exposure co ntrol

L1 CONT

PRCB SCDB

24VDC

L1 CONT

L1 INVB

24VDC
PGND

DCPS2

2 UNIT EXPLANATION

L1 (exposure lamp) is driven by the L1 INVB (L1
inverter) and is controlled by the PRCB (printer control
board) via the SCDB (scanner drive board).

1. Operation

L1 is a xenon lamp driven by the inverter circuit.
The xenon lamp can emit a constant quantity of
light and generates less heat than other lamps,
requiring neither light quantity controller circuit
nor thermal protector circuit that have been used
in the conventional machines . Howe ver , since L1
is held lit when the exposure unit is nonopera­tional in the DF mode, a FM7 (scanner cooling)
is installed in the read section.

2. Signals

a. Output signals

(1) L1 CONT (PRCB to SCDB to L1 INVB)

L1 ON/OFF control signal.
[L]: L1 ON
[H]:L1 OFF

LV

L1

HV

2-C-4

READ SECTION

[5] Original Read Control

CCD

ADB

ICB IFB ICB

Original read control is performed by the ADB (A/D
converter board) and CCD sensor installed in the ADB .

1. Operation

The light reflected by the exposed original is
input to the CCD sensor through the lens. The
analog voltage corresponding to the quantity of
input light is A/D-converted in the ADB, being
output to the ICB (image control board).

a. Original read

The original read timing is as follows:

(1) Platen mode

Specified interval after exposure unit turns PS6
(original HP) ON.

(2) DF mode

After lapse of the specified time after the origi­nal’s leading edge turns ON PS308 (Original
conveyance).

[6] APS Control

5VDC

PS62

SGND

PS63

PS64

PS65

PS66

PS67

PS68

PRCB ICB IFB

The APS method used in the platen mode is different
from that used in the DF mode.
The signal read by the APS sensor o r the original siz e
detection sensor of the RADF is proces sed by the I CB
(image control board).

1. Operation

a. APS detection

(1) DF mode

The original size is detected according to the
combination of ON/OFF states of PS302 (origi­nal size detection 1) and PS303 (original size
detection 2) and the resistance value of VR301
(original size detection).

PS62

PS63

PS64

PS65

PS66

PS67

PS68

5VDC
SGND

DCPS1

2 UNIT EXPLANATION

2-C-5

READ SECTION

(2) Platen mode

2 UNIT EXPLANATION

The paper size is detected according to the co m­bination of ON/OFF states of PS62 (APS 1),
PS63 (APS 2), PS64 (APS 3), PS65 (APS 4),
PS66 (APS 5), PS67 (APS 6), and PS68 (APS

7).
The APS sensor consists of LEDs and photosen­sors. Lights emitted from the LEDs is reflected by
the original and received by photosensors.

PS63 PS62 PS68

PS66
PS64

Paper exit side

PS67
PS65

Photo sensor
LED

Relationships between sensors and original
sizes are as follows:

Sensor

Paper
size

B5R
B5
B4
A4R
A4
A3

8.5 x 11R

8.5 x 11

8.5 x 14
11 x 17
Min. size

PS62 PS63 PS64 PS65 PS66 PS67 PS68

z

zzz
zzzzz
zzz

zzzzz
zzzzzzz

zz

zzzz
zz z z
zzz zzz

z ON

OFF

b. APS detection timing

The APS detection timing differs between the
platen mode and DF mode.

(1) DF mode

When the DF mode is selected or original is set
on the RADF original feed tray, APS detection
takes place using PS302 (original size detection

1), PS303 (original size detection 2), and VR301
(original size detection).

(2) Platen mode

When RADF is closed and PS315 (APS timing)
turns ON, APS detection takes place using PS62
to PS68.

2. Signals

a. Input signals

(1) PS62 (PS62 to ICB IFB)

Paper size detection signal.
[L]: Paper is detected.
[H]:Paper is not detected.

(2) PS63 (PS63 to ICB IFB)

Paper size detection signal.
[L]: Paper is detected.
[H]:Paper is not detected.

(3) PS64 (PS64 to ICB IFB)

Paper size detection signal.
[L]: Paper is detected.
[H]:Paper is not detected.

(4) PS65 (PS65 to ICB IFB)

Paper size detection signal.
[L]: Paper is detected.
[H]:Paper is not detected.

(5) PS66 (PS66 to ICB IFB)

Paper size detection signal.
[L]: Paper is detected.
[H]:Paper is not detected.

(6) PS67 (PS67 to ICB IFB)

Paper size detection signal.
[L]: Paper is detected.
[H]:Paper is not detected.

(7) PS68 (PS68 to ICB IFB)

Paper size detection signal.
[L]: Paper is detected.
[H]:Paper is not detected.

2-C-6

READ SECTION

[7] AE Control

CCD

ADB

ICB IFB ICB

The CCD sensor detects the image density on an orig­inal during AE scanning to select the optimum copy
gamma correction curve.
AE processing is controlled by the ICB (image cont rol
board).

1. Operation

a. AE detection

(1) Platen mode

The image density on an original is measured
while the exposure unit moves from the home
position to the leading edge of the original after
depression of the START button.

<AE sampling area>

(1) Normal copy

10mm inside perimeter of original size detected
by APS.

(2) Non-image area erasure mode

Entire original area detected by forward scan­ning.

(3) DF mode

The image at the leading edge of the original is
read when the START button is pressed.
The read data is used to measure the image den­sity on the original.

<AE sampling area>

(1) Main scanning direction

• 10-mm area inside the original detected by
APS

(2) S ub scanning direction

Range between 2mm to 7.3mm from the leading
edge of the original.

2 UNIT EXPLANATION

2-C-7

2 UNIT EXPLANATION

WRITE UNIT

[1] Composition

Index sensor board

WRITE UNIT

Cylindrical lens 1

Polygon mirror

Cylindrical lens 2

3rd mirror

2 UNIT EXPLANATION

Laser driver board LD2

2nd mirror

fθ lens 2

Collimator lens unit 1

fθ lens 1

Laser driver board LD1

[2] Mechanisms

Mechanism Method

*1 Scan Polygon mirror

Light source Laser diodes (two)

*2 Positioning Index sensor

*3 Laser beam

combining

*1 Path of laser light

The light output from semiconductor laser is radi­ated onto the OPC drum via the collimator lens,
compression prism, fine adjustment prism, beam
combining prism, cylindrical lens 1, polygon mir­ror, fθ lens 1, fθ lens 2, second m irror , cylindrical
lens 2, and third mirror.

Rotational speed:
24,803.1 rpm (400 dpi)
37,204.7 rpm (600 dpi)

(Output: Max. 20 mW)

Fine adjustment prism
Beam combining prism

Collimator lens unit 2

Beam combining prism

Semiconductor
laser LD2

CY2 lens

3rd mirror

Polygon
mirror

Glass cover

Index mirror

Index sensor

OPC drum

Compression prism

Semicon­ductor
laser LD1

Collimator
lens unit

Beam
combining
prism

CY1 lens

2nd mirror

fθ lens 2

fθ lens 1

2-D-1

Polygon Cooling Fan

WRITE UNIT

*2 Positioning

Each laser beam is positioned by the compres­sion prism and fine adjustment prism.

*3 Laser beam combining

Two laser beams output at right angle to each
other are redirected in the same direction using
the beam combining prism.

2 UNIT EXPLANATION

Semiconductor l ase r 1

Laser 1 beam passes

Laser 2 beam
reflected

Beam combining prism

Semiconductor
laser 2

[3] M17 (P olygon) Control

M17 EM

M17 CLK

M17 CONT

PRCB

24VDC

PGND

DCPS2 PMDB

M17 (polygon) is driven by the PMDB (polygon driver
board) and is controlled by the PRCB (printer control
board).

1. Operation

a. Explanation of operation

M17 is a 3-phase brushless DC motor which is
driven by the 3-phase bipolar method. The cur­rent flowing through the coil is switched accord­ing to the position of the rotor detected by the
position sensor (magnetic sensor) in the motor.
This motor rotates the polygon mirror to scan the
laser beams from LDB1 and 2 (laser driver
boards 1 and 2) in the axial direction of the drum.
Its rotation is held constant by PLL control.

b. Rotational speed

36VDC is used to drive M17. The rotation speeds
are as follows:

Resolution Rotational speed (rpm)

400 dpi 24,803.1 rpm
600 dpi 37,204.7 rpm

SGND

24VDC

M17 MAG A’

M17 MAG A
M17 MAG B’
M17 MAG B
M17 MAG C’

M17 MAG C
M17 DRIVE C
M17 DRIVE B
M17 DRIVE A

M17

2. Signals

a. PRCB input signals

(1) M17 EM (PMDB to PRCB)

This signal indicates the clock synchronization
state of M17.
[L]: Synchronous (normal)
[H]:Asynchronous (abnormal)

2-D-2

b. PRCB output signals

(1) M17 CONT (PRCB to PMDB)

This signal turns ON/OFF M17.
[L]: M17 ON
[H]:M17 OFF

(2) M17 CLK (PRCB to PMDB)

This is a reference clock signal for PLL-control­ling M17 in PMDB.

c. PMDB input signals

(1) M17 MAG A/A’ (M17 to PMDB)
(2) M17 MAG B/B’ (M17 to PMDB)
(3) M17 MAG C/C’ (M17 to PMDB)

Output signals from the position sensor (mag­netic sensor) incorporated in M17.
The PMDB detects the position of the motor rota­tor using these signals, switching among out­puts, M17 DRIVE A to C.

d. PMDB output signals

(1) DRIVE A to C (PMDB to M17)

M17 drive signals.
M5 DRIVE A to C supplies the corresponding
voltages to M17. Pulses of the voltages applied
to M17 are shown below . The pulse widths of the
PMDB output signals change as shown below
depending on the state of M17 rotation, changing
the effective values of the voltages supplied to
M17. Thus, the M17 speed can be controlled.

WRITE UNIT

2 UNIT EXPLANATION

M5 DRIVE A

M5 DRIVE B

M5 DRIVE C

2-D-3

WRITE UNIT

[4] Image Write Control

2 UNIT EXPLANATION

ADB

ICB

DCPS1

DCPS2

5VDC

SGND

24VDC

PGND

M24 PWR A
M24 PWR B

M24 DRIVE A

M24 DRIVE A’

M24 DRIVE B

M24 DRIVE B’

5VDC

SGND

M INDEX 1

SGND

M INDEX 2

SGND

S INDEX1

SGND

S INDEX 2

SGND
HL VL

IPR

SGND

5VDC

SGND

LD1 SH

LD1 ENB

LD1 VIDEO

SGND

LD1 ALM

LD1DCLK

LD1 DI
LD1 LD
LD1 PR

5VDC

SGND

LD2 SH

LD2 ENB

LD2 VIDEO

SGND

LD2 ALM

LD2 DCLK

LD2 LD
LD2 AD
LD2 PR

M24

INDEXSB

LDB1

LDB2ICB IFB

The analog image data from the CCD sensor is A/D­converted by the ADB (A/D conv erter board), then sent
to the ICB (image control board) for data processing.
The processed image data is converted into a laser
beam according to the control signal received from the
ICB through the ICB IFB (ICB I/F board), then the b eam
is radiated onto the drum surface. Two lasers are pro-

vided to write two lines of image data per scan. The
write start position is detected by the INDXSB (index
sensor board). The ICB has an E-RDH (electronic
RDH processing) function to store digitized data. Var­ious editing functions can be performed based on this
data.

2-D-4

WRITE UNIT

1. Operation

a. Image processing

The following processing is performed by the ICB
(image control board):

(1) AOC (Auto Offset Control)

During shading correction, a read operation
takes place while L1 (exposure lamp) is OFF, and
the analog offset voltage of the output from the
CCD sensor is automatically adjusted so t hat the
resulting level is the lower limit of the A/D con­verter.

(2) AGC (Auto Gain Control)

During shading correction, the white reference
plate is read, and the amplification of the a nalog
output from the CCD sensor is automatically
adjusted so that the resulting level is the up per of
the A/D converter.

(3) Shading correction

<Timing>

• When SW1 (main switch) is turned ON
(4) Brightness/density conver sion
(5) EE processing
(6) Text/dot pattern judgment
(7) Filtering/magnification change processing
(8) Magnification change processing
(9) Copy gamma correction
(10)Skew correction
(11)Error diffusion processing
(12)Data compression
(13)Write density control

b. Write

The ICB (image control board) sends image data
on a pixel basis to LDB1 and LDB2 according to
the control signals from the PRCB (printer con­trol board).
LDB1 and LDB2 cause the lasers to emit for a
period corresponding to the image data. This
laser light is radiated onto the drum surface.

(1) MPC (Maximum Power Control)

ICB informs LDB1 and LDB2 of the maximum
output value and sets that value for the laser
beam emission. LDB1 and LDB2 store this set­ting value and maintain the quantity of the laser
beam emission using the APC (Auto P ow er Con­trol).
<MPC timing>

• When SW1 (main switch) is turned ON
(2) APC (Auto Power Control)

The ICB outputs an APC start instruction to the
LDB at the following timing, after MPC is set.

<APC timing>

• The LDB1 and LDB2 automatically monitor the
laser drive current one line at a time, and con­trols it so that the light intensity remains the
MPC value.

(3) Write timing

a) Main scanning direction

Using INDEX signal from INDXSB, deter­mines the laser write reference position for
each scan in the drum rotation direction, and
writes the image to copy paper using the
paper position information derived from the
paper position detection by PS1 (paper mis­centering).

INDEX

Laser
output 1
Laser
output 2

ab c d e

Image area

1st scanning

2nd scanning

Symbol Description

a Laser goes ON for first scan.
b Index sensor goes ON.
b-c

c-d
d-e

The timing at the left is controlled
by counting the LD1 IRCLK and
LD2 IRCLK signals. It differs
depending on the document size.

b) Sub scanning direction

Specified interval after PS44 (registration)
detects the tip of the copy paper.

(4) Las er beam position correction

a) Main scanning direction

The index sensor detects the devi ation of the
positions of the two beams. This erro r is c or­rected by changing the timing of the light
emission from the laser.

b) Sub scanning direction

The index sensor detects the devi ation of the
positions of two beams in order to change the
angle of the fine adjustment prism of the LD1
laser using M24 (laser correction), thus
adjusting the vertical angle of the beam.

2 UNIT EXPLANATION

2-D-5

WRITE UNIT

2. Signals

a. ICB IFB input signals

(1) M INDEX 1, 2 (INDEXSB to ICB IFB)

This is an index signal used to detect deviation of
vertical scanning.

(2) S INDEX 1, 2 (INDEXSB to ICB IFB)

This is an index signal used to detect deviation of
horizontal scanning.

(3) IPR (INDEXSB to ICB IFB)

This signal monitors the INDEXSB power supply .
[H]:Normal
[L]: Abnormal

(4) LD1 ALM (LDB1 to ICB IFB)

2 UNIT EXPLANATION

This signal indicates the state of the LD1 laser
drive current.
[H]:Normal
[L]: Abnormal

(5) LD1 PR (LDB1 to ICB IFB)

LD1 power supply monitor signal.
[H]:Normal
[L]: Abnormal

(6) LD2 ALM (LDB2 to ICB IFB)

This signal indicates the state of the LD2 laser
drive current.
[H]:Normal
[L]: Abnormal

(7) LD2 PR (LDB2 → ICB IFB)

LD2 power supply monitor signal.
[H]:Normal
[L]: Abnormal

b. ICB IFB output signals

(1) M24 PWR A (ICB IFB to M24)

M24 A-phase drive signal.

(2) M24 PWR B (ICB IFB to M24)

M24 B-phase drive signal.

(3) M24 DRIVE A/A’ (ICB IFB to M24)

M24 A-phase drive pulse signal.

(4) M24 DRIVE B/B’ (ICB IFB to M24)

M24 B-phase drive pulse signal.

(5) LD1 SH (ICB IFB to LDB1)

One scan line equivalent APC sampling signal.

(6) LD1 ENB (ICB IFB to LDB1)

Laser APC function ON/OFF control signal.
Laser beam emission stops when it is OFF.

(7) LD2 SH (ICB IFB to LDB2)

One scan line equivalent APC sampling signal.

(8) LD2 ENB (ICB IFB to LDB2)

Laser APC function ON/OFF control signal.
Laser beam emission stops when it is OFF.

(9) LD1 VIDEO (ICB IFB to LDB1)

LD1 laser image signal.

(10)LD2 VIDEO (ICB IFB to LDB2)

LD2 laser image signal.

(11)LD1 DCLK (ICB IFB to LDB1)

LD1 clock signal for MPC value data transmis­sion.

(12)LD1 DI (ICB IFB to LDB1)

LD1 data signal for MPC.

(13)LD1 AD (ICB IFB to LDB1)

LD1 MPC value storage command signal.

(14)LD2 DCLK (ICB IFB to LDB2)

LD2 clock signal for MPC value data transmis­sion.

(15)LD2 DI (ICB IFB to LDB2)

LD2 data signal for MPC.

(16)LD2 AD (ICB IFB to LDB2)

LD2 MPC value storage command signal.

2-D-6

DRUM UNIT

[1] Composition

Cleaning/toner
recycle unit

Cleaning/toner recycle unit

Charging corona unit

Developing unit

Charging corona unit

PCL

TSL

DRUM UNIT

Separation claws

2 UNIT EXPLANATION

Separation claw solenoid (SD4)

Developing unit

Transfer and separation corona unit

[2] Mechanisms

Mechanism Method

Carriage support F ixed rail
PCL/TSL LED
Auxiliary separation Separation claws

*1

Conveyance assistance Ratchet wheel

*2

The drum unit is an integral assembly consisting of a
drum, charging corona unit, dev eloping un it, cleaning/
toner recycle unit, PCL, and separation claws.

*1 Auxiliary separation

• To prevent paper jamming, three separation
claws are used to separate paper from the
drum forcibly. These separation claws are
pressed against the drum or detached from it
by turning ON/OFF the separation claw sole­noid (SD4).

• To prevent a specific part of image copied
paper from being stained and to prevent the
drum from being scratched, the sw ing mecha-

nism slides the separation claws about 5 mm
back and forth in parallel with the drum sur­face.

Separation claw solenoid (SD4)

Separation claw

*2 Conveyance assistance

The thick paper conveyance ability has been
improved by the use of ratchets.

2-E-1

DRUM UNIT

[3] Separation Claw Control

24VDC

SD4 DRIVE

M2CONT

M2EM

PRCB

MS2 MS1

24VDC

PGND

2 UNIT EXPLANATION

The separation claw is driven by SD4 (separation
claw). The vibration of the separation claw is put in by
M2 (drum). SD4 is controlled directly by PRCB (printer
control board).

1. Operation

a. Separation claw ON/OFF control

SD4 is a pull-type solenoid po wered by 24 VDC .
It turns ON to press separation claws against the
drum to help image copied paper separate.

(1) SD4 operation timing

SD4 turns ON after a lapse of specified time from
turning ON of PS45 (leading edge detection) in
the second paper fe ed section. It turns OFF after
a lapse of the time set by the PRCB timer.

b. Separation claw swing control

Separation claws are swung by M2 (drum) via
the cam mechanism.

2. Signals

a. Output signal

(1) SD4 DRIVE (PRCB to S D4 )

SD4 drive control signal.
[L]: SD4 ON
[H]:SD4 OFF

DCPS2

SD4

M2

[4] Paper Guide P late Control

GP CONT

PRCB

24VDC

PGND

DCPS2

ADUSDB

To prevent toner from adhering to the paper guide
plate, a constant voltage is applied to the paper guide
plate. This voltage is supplied from HV2 (high voltage
unit 2) and is controlled by the serial data sent from the
PRCB (printer control board) via the ADUSDB (ADU
stand drive board). When t he front door of this machine
opens or closes, MS1 (interlock 1) or MS2 (interlock 2)
operates to interrupt the DC power supply to HV2,
stopping the voltage application to the paper guide
plate.

1. Operation

a. ON/OFF timing

Turning ON/OFF in sync with M2 (drum)

b. Applied voltage

-500 VDC

2. Signal

a. Output signal

(1) GP CONT (ADUSDB to HV2)

This signal controls turning ON/OFF the voltage
application to paper guide plate.
[L]: Voltage applied
[H]:Voltage not applied

GP

HV2

2-E-2

DRUM UNIT

[5] Drum Potential Control

DPS DRIVE A
DPS DRIVE B

DPS ANG 1
DPS ANG 2

DPSB

PRCB

DCPS2

DPS ANG

SGND

24VDC

PGND

The drum potential is detected by the DPS (drum
potential sensor) and send the PRCB (printer control
board) via the DPSB (drum potential sensor board).

1. Operation

Drum potential control is performed to keep the
drum surface potential constant and maintain
image quality regardless of the usage environ­ment or the number of copies.

(1) Method

The image is created on the drum surface by the
difference in the exposure potential and de velop­ing bias. A patch is created with laser PWM max­imum.
The developing bias is corrected so that the dif­ference between the after exposure potential
(solid black area) and the developing bias is
always kept constant and the charging current
and the grid voltage are corrected so that the dif­ference between the before exposure potential
and developing bias is always kept constant.

(2) Timing

a) When the fixing temperature is lower than

50°C at power ON.

b) At the end of job after every 5,000 copies.

DPS

2. Signals

a. PRCB Input signals

(1) DPS ANG (DPSB to PRCB)

Analog signal corresponding to the drum charg­ing potential.

b. DPSB Input signals

(1) DPS ANG 1 and 2 (DPS to DPSB)

Analog signal corresponding to the drum charg­ing potential.

c. DPSB output signals

(1) DPS DRIVE A and B (DPSB to DPS)

DPS (drum potential) drive signal.

2 UNIT EXPLANATION

2-E-3

2 UNIT EXPLANATION

CORONA UNIT SECTION

[1] Composition

<Charging corona unit>

Charging corona wires

PCL

Charging wire cleaning motor
(M23)

Charging wire cleaning material

<Transfer and separation corona unit>

Transfer entrance
guide plate

Plunging prevention plate

Separation corona unit

CORONA UNIT SECTION

Guide rollers

Transfer
corona unit

2 UNIT EXPLANATION

[2] Mechanisms

Mechanism Method

*1 Charging Scorotron (DC negative corona

discharge).
Discharge wire: Tungsten, 0.06
mm dia. (gold-plated skin path:
with automatic wire cleaner).
Grid control: Gold-plated stain­less plate.

*2 Transf er DC posit ive corona discharge.

Discharge wire: Oxide film tung­sten, 0.06 mm dia., with auto­matic wire cleaner.

Separation AC/DC corona discharge.

Discharge wire: Oxide film tung­sten, 0.06 mm dia., with auto­matic wire cleaner.

*1 Cleaning the charging wire

The charging corona unit has wire cleaning
pads. The charging wire cleaning pad drive
motor moves the charging wire cleaning pad
back and forth, removing toner and dirt from the
wires.

Charging wire cleaning material

Charging wire

*2 Cleaning the transfer and sepa ration wires

The transfer and separation corona unit has a
wire cleaner pads. The transfer and separation
wire cleaning pads drive motor moves the trans­fer and separation wire cleaning pads back and
forth, removing toner and dirt from the wires.

Transfer wire cleaning
material

Transfer wire

Separation wires

2-F-1

Separation wire cleaning mate rial

CORONA UNIT SECTION

[3] Charging Control

C CONT1
C CONT2

C SHIFT

SGND

G SHIFT

PRCB

24VDC

2 UNIT EXPLANATION

PGND

DCPS2 HV1

Charging control is conducted by serial data tra nsmit­ted from PRCB (printer control board) to HV1 (high
voltage unit 1). The applied voltage for the charging
wires are supplied by HV1.

1. Operation

a. Charging

A Scorotron charging method is used. 24 VDC
supplied from DCPS2 is raised to a negative DC
voltage which is then discharged after being
applied to the charging wire.
When the front door of this machine opens or
closes, MS1 (interlock 1) or MS2 (interlock 2)
operates to interrupt the DC power supply to
HV1, stopping the voltage supply to the charging
corona unit and charging grid.

b. Grid voltage

The grid voltage is output from HV1 to the charg­ing plate.

C SIG

MS2 MS1

CHARGING

2. Signals

a. Input signal

(1) C SIG (HV1 to PRCB)

Leak or short detection signal.
[L]: Normal
[H]:Abnormal

b. Output signals

(1) C CONT1, 2 (PRCB to HV1)

Charging 1/2 output ON/OF control signal.
[L]: Charging voltage ON
[H]:Charging voltage OFF

(2) C SHIFT (PRCB to HV1)

Charging corona unit output level control signal.
The output to the charging corona unit is con­trolled according to the duty ratio of the pulse
(PWM) signal sent from the PRCB.

C SHIFT duty 20% to 80%
Charging output range -500µA to -1900µA

(3) G SHIFT (P RCB to HV1)

Charging grid output level control signal.
The output to the charging grid is controlled
according to the duty ratio of the pulse (PWM)
signal sent from the PRCB.

G SHIFT duty 20% to 80%
Grid voltage output range -400 V to -1000 V

2-F-2

CORONA UNIT SECTION

[4] Transfer/Separation Control

24VDC
PGND

DCPS2

MS2 MS1

24VDC

T CONT

S CONT

SEL

T SIG

S SIG
SGND
PGND

ADUSDB

S SHIFT(DC)

S FB(AC)
S FB(DC)

S SHIFT(AC)

T SHIFT

PRCB HV2

The transfer and separation corona unit is controlled by
the PRCB (printer control board) and ADUSDB (ADU
stand drive board) via the HV2 (high voltage unit 2).
Between the PRCB and ADUSDB, signals are
exchanged using serial data. When the front door of
this machine opens or closes, MS1 (interlock 1) or MS2
(interlock 2) operates to interrupt the DC pow er supply
to HV2, stopping the voltage supply to the tr ansfer and
separation corona unit.

1. Operation

a. Transfer

Positive D C high voltage is used for toner transf er
to the drum surface.

b. Separation

AC high voltage is used for toner separation from
the drum surface.

2. Signals

a. PRCB input signals

(1) S FB (AC) (HV2 to PRCB)

Toner separation (AC) current feedback signal.
This signal monitors the toner separation (AC)
current. It is a 0 to 5V analog s ignal corr espond ­ing to the output level.

(2) S FB (DC) (HV2 to PRCB)

Transfer and separation (DC) current feedback
signal.
This signal monitors the toner transfer and sep­aration (DC) current. It is a 0 to 5V analog signal
corresponding to the output level.

SEPARATION

TRANSFER

b. PRCB output signals

(1) T SHIFT (PRCB to HV2)

Transfer corona unit output level control signal.
This signal controls the level of the output to the
transfer corona unit according to t he duty ratio of
the pulse (PWM) signal sent from the PRCB.

T SHIFT duty 20% to 80%
Transfer DC output range 70µA to -700µA

(2) S SHIFT (DC) (PRCB to HV2)

Separation corona unit output level control sig­nal.
This signal controls the level of the output (DC
bias component) to the separation corona unit
according to the duty ratio of the pulse (PWM)
signal sent from the PRCB.

S SHIFT duty 20% to 80%
Separation DC output range 0µA to -300µA

(3) S SHIFT (AC) (PRCB to HV2)

Separation corona unit output level control sig­nal.
This signal controls the level of the output (AC
component) to the separation corona unit
according to the duty ratio of the pulse (PWM)
signal sent from the PRCB.

S SHIFT duty 20% to 80%
Separation AC output range 500µA to 1400µA

c. ADUSDB input signals

(1) T SIG (HV2 to ADUSDB)

Leak or short toner transfer abnormality detec­tion signal.
[L]: Normal
[H]:Abnormal

(2) S SIG (HV2 to ADUSDB)

Leak or short toner separation abnormality
detection signal.
[L]: Normal
[H]:Abnormal

2 UNIT EXPLANATION

2-F-3

CORONA UNIT SECTION

d. ADUSDB output signals

(1) T CONT (ADUSDB to HV2)

Transfer corona unit output ON/OFF control sig­nal.
[L]: Transfer corona unit ON
[H]:T ransfer corona unit OFF

(2) S CONT (ADUSDB to HV2)

Separation corona unit output ON/OFF control
signal.
[L]: Separation corona unit ON
[H]:Separation corona unit OFF

(3) SEL (ADUSDB to HV2)

2 UNIT EXPLANATION

Feedback switcho ver signal.
This signal determines whether the feedback
signal of the transfe r and separation (DC) current
is used for toner separation monitor or toner
transfer monitor.
[L]: Toner separation monitor
[H]:Toner transfer monitor

[5] M23 (Charge r Cleaning) Cont rol

5VDC

PS41

PS42

M23

M23 (charger cleaning) uses a DC motor with a 12V
drive, and is controlled directly by PRCB (printer con­trol board). Related signals are PS41 (charger clean­ing HP) and PS42 (charger cleaning limit).

1. Operation

a. Purpose of driving

M23 is used to drive the charging wire cleaning
pad.

b. Operation timing

The charging corona wires are cleaned when the
main switch is turned ON, when the fixing tem­perature is lower than 50°C (122°F). They are
also cleaned when the specified copy count is
reached.
* Changeable with 25 mode DIPSW.

c. Cleaning operation

The home position of the c harging w ire cl eaning
pad is on the rear side of machine. The charging
wire cleaning pad operates as follows:

Charging wire cleaning
pad HP

PS41 PS42

PS41
SGND

PS42

M23
DRIVE1
M23

PRCB

DRIVE2

12VDC
5VDC
SGND

DCPS1

Charging wire cleaning
pad limit

Cleaning (forward)

Cleaning (return)

2-F-4

Home search (forward)

Home search (return)

CORONA UNIT SECTION

2. Signals

a. Input signals

(1) PS41 (PS41 to PRCB)

Charging wire cleaning pad home position
detection signal.
This signal detects the reference position of the
charging wire cleaning pad home position.
[L]: HP detected
[H]:HP not detected

(2) PS42 (PS42 to PRCB)

Charging wire cleaning pad limit detection sig­nal.
This signal detects the limit position of charging
wire cleaning pad.
[L]: Limit position detected
[H]:Limit position not detected

b. Output signals

(1) M23 DRIVE1, 2 (PRCB to M23)

M23 drive control signal.
The drive direction of M23 is controlled by switch­ing the drive current directions of two signals.

Status M23 DRIVE1 M23 DRIVE2

Forward strok e of
cleaning

Return stroke of
cleaning

Stop

HL

LH
LL

[6] M18 (Transfer/Separation Cleaning)

Control

M18

M18

DRIVE1

M18

DRIVE2

PRCB

5VDC

SGND

DCPS1

MS2 MS1

24VDC

PGND

DCPS2

M18 (transfer/separation cleaning) is a 24 VDC motor
which is controlled by the PRCB (printer control board)
via the ADUSDB (ADU stand drive board). Between
the PRCB and ADUSDB, signals are e xchanged us ing
serial data. Related signals are PS11 (transfer/sepa­ration wire cleaning pad HP) and PS12 (transfer/sep­aration wire cleaning pad limit). W hen the f ront right or
left door of this machine opens or closes, MS1 (inter­lock 1) or MS2 (interlock 2) operates to interrupt the DC
power supply to PRCB, stopping the M18.

1. Operation

a. Purpose of driving

M8 is used to drive the transfer and separation
wire cleaning pads.

b. Operation timing

The transfer and separation wires are cleaned
when the main switch is turned ON, when the fix­ing temperature is lower than 50°C, or when th e
specified copy count is reached.
* Changeable with 25 mode DIPSW.

5VDC

PS11

SGND

PS12

ADUSDB

PS11

PS12

2 UNIT EXPLANATION

2-F-5

CORONA UNIT SECTION

c. Cleaning operation

The home position of the transfer and s eparation
wire cleaning pads is on the front side of
machine. The transfer and separation wire
cleaning pads operate as follows:

Transfer/Separation wire
cleaning pad HP

Cleaning (forward)

2 UNIT EXPLANATION

Cleaning (return)

Home search (forward)

Home search (return)

2. Signals

a. PRCB input signals

(1) PS11 (PS11 to PRCB)

Transfer and separation wire cleaning pads
home position detection signal.
This signal detects the reference position of the
transfer and separat ion wire cleaning pads home
position (front side).
[L]: HP detected
[H]:HP not detected

(2) PS12 (PS12 to PRCB)

T ransf er and separation wire cleaning pads driv e
limit detection signal.
This signal detects the rear limit position of the
transfer and separation wire cleaning pads.
[L]: Limit position detected
[H]:Limit position not detected

b. ADUSDB output signals

(1) M18 DRIVE1, 2 (ADUSDB to M18)

M18 drive control signal.
The drive direction of M18 is controlled by switch­ing the drive current directions of two signals.

Status M18 DRIVE1 M18 DRIVE2

Forward stro ke of
cleaning

Return stroke of
cleaning

Stop

Transfer/Separation wire
cleaning pad limit

PS12PS11

HL

LH
LL

[7] PCL/TSL Control

24VDC

PGND

DCPS2

24VDC

TSL CONT

ADUSDB

24VDC

PCL CONT

PRCB

LEDs are used for PC L (pre-charging exposure lamp)
and TSL (transfer synchronization lamp). PCL is
driven by PRCB (printer control board). TSL is driven
by ADUSDB (ADU stand drive board) , and the control
is conducted by PRCB.

1. Operation

PCL is turned ON/OFF in sync with M2 (drum).
TSL turns ON after a lapse of specified time from
turning ON of PS45 (leading edge detection) of
the second paper feed section. It turns OFF after
a lapse of specified time from detection of the
trailing edge of copy paper.

2. Signals

a. Output signals

(1) PCL CONT (PRCB to PCL)

PCL ON/OFF control signal.
[L]: PCL ON
[H]:PCL OFF

(2) TSL CONT (ADUSDB to TLS)

TSL ON/OFF control signal.
[L]: TSL ON
[H]:TSL OFF

TSL

PCL

2-F-6

DEVELOPING UNIT

[1] Composition

Developing unit cover

DEVELOPING UNIT

Developing regulation plate

2 UNIT EXPLANATION

Developing sleeve

Splash prevention
sheet (upper)

[2] Mechanisms

Mechanism Method

Developing 2-component developer
Developing bias DC bias
Developer

agitation

1. The developing unit drive motor (M3)
drives the following parts via the gear
unit at the back:

• Developing sleeve

• Agitator wheel

• Agitator screws

2. Flow of developer

The developer inside t he developing unit is sup­plied to the developing sleeve by the agitator
wheel, and maintained at a constant thickness by
the developing regulation plate (bristle height
regulation plate). The developer remaining on
the developing sleeve is returned to the agitator
screws.

Main agitator
Auxiliary agitator

Developing
sleeve

Drum

Agitator wheel

Agitator
wheel

Developing regulation plate

Agitator screws

Agitator screw

2-G-1

DEVELOPING UNIT

[3] M3 (Developing Unit Drive) Control

MS2 MS1

24VDC

PGND

DCPS2

M3 CONT

M3 CLK

M3 EM

PRCB

2 UNIT EXPLANATION

M3 (developing) is controlled by the PRCB (printer
control board) and the motor drive power is supplied by
DCPS2 (DC power supply unit 2). When the front left
or right door of this machine opens or closes, MS1
(interlock 1) or MS2 (interlock 2) operates to interrupt
the DC power supply to M3, stopping the voltage sup­ply to the developing sleeve.

1. Operation

M3 which is the 24V driven DC motor drives the
developing sleeve and agitator. M3 equipped
with speed control circuit send the r ota tion error
signal to PRCB when PLL lock is released longer
than the specified time period. M3 starts after the
specified time interval from the start switch is
ON, and stops after the specified time interval
from the charging wire unit stops charging.

2. Signals

a. Input signals

(1) M3 EM (M3 to PRCB)

M3 fault detection signal.
[H]:Abnormal rotation (when PLL is unlocked for

more than 1.5 seconds)

[L]: Normal rotation

b. Output signals

(1) M3 CONT (PRCB to M3)

M3 drive control signal.
[L]: M3 ON
[H]:M3 OFF

[4] Developing Bias Control

24VDC

5VDC

SGND
B CONT
B SHIFT

PRCB

SGND

DCPS1

24VDC
24VDC

PGND

DCPS2

B FB

5VDC

MS2 MS1

HV1

M3

The developing bias is controlled by PRCB (printer
control board) via the HV1 (h igh voltage unit 1). When
the front left or right door of this machine opens or
closes, MS1 (interlock 1) or MS2 (interlock 2) operates
to interrupt the DC power supply to HV1, stopping the
voltage supply to the developing sleeve.

1. Operation

The developing bias voltage is applied to the
developing sleeve based on the M2 (drum) rota­tion state signal.

2. Signals

a. Input signals

(1) B FB (HV1 to PRCB)

Developing bias vo ltage feedback signal.
This signal monitors the deve loping bias voltage.
It is an 0V to 5V analog signal corresponding to
the output level.

b. Output signals

(1) B CONT (PR CB to HV1)

Developing bias output ON/OFF control signal.
[L]: Developing bias ON
[H]:Developing bias OFF

(2) B SHIFT (PRCB to HV1)

Developing bias output level control signal.
The developing bias output level is controlled
according to the duty ratio of the pulse (PWM)
signal sent from the PRCB.

B SHIFT duty 20% to 80%
Developing bias output ra nge -300 V to -800 V

BIAS

2-G-2

DEVELOPING UNIT

[5] Toner Density Control

24VDC
24VDC

M11 DRIVE A
M11 DRIVE A

M11 DRIVE B
M11 DRIVE B

PRCB

DCPS2

The toner density is controlled directly by PRCB
(printer control board) by controlling M11 (toner
supply 1). When the front right or left door of this
machine opens or closes, MS1 (interlock 1) or
MS2 (interlock 2) operates to interrupt the DC
power supply to the motor, stopping the M11.

1. Operation

a. Toner density detection

Concerning the toner density, the reference
patch density is detected by a patch detection
method. This method outputs the corresponding
analog voltage signal to the PRCB.
The PRCB compares the detected voltage with
the reference value to determine whether toner
must be added.

b. Toner supply operation

Upon read of the patch, M11 is turned ON to sup­ply toner. The time needed to add tone r depends
on the paper size.

24VDC

PGND

MS2 MS1

M11

2. Signals

a. Output signals

(1) M11 DRIVE A, A

M11 A-phase drive signal.

(2) M11 DRIVE B, B

M11 B-phase drive signal.

(PRCB to M11)

(PRCB to M11)

2 UNIT EXPLANATION

2-G-3

DEVELOPING UNIT

[6] Dmax Control

2 UNIT EXPLANATION

DCPS2

DCPS1

TH5

24VDC
24VDC

PGND

12VDC

5VDC

SGND

MS2 MS1

TH5 ANG1
TH5 ANG2

M2 CONT

M2 F/R

SGND

M2 EM

M3 CONT

M3 CLK

M3 EM

DPS ANG

AGND

5VDC

Dmax LED CONT

/Dmax LED Vref

JAM LED CONT

Dmax SIG

Dmax MONI

JAM SIG

PRCB

M2

M3

DPS DRIVE A
DPS DRIVE B

DPS ANG 1

DPS ANG 2

DPSB

TCSB

DPS

Dmax control is performed by the TCSB (toner
control sensor board), M2 (drum), M3 (develop­ing), and so on. These parts are controlled by the
PRCB (printer control board). Related boards
and sensors are DPSB (drum potential sensor
board), DPS (drum potential sensor), and TH5
(drum temperature sensor).
When the front right or left door of this machine
opens or closes, MS1 (interlock 1) or MS2 (inter­lock 2) operates to interrupt the DC power supply
to the motor, stopping the M2 and M3.

1. Operation

The purpose of Dmax control is to adjust the
maximum density to the ref erence le vel for each
machine.

a. Dmax control

(1) Method

Latent images are created several times at the
maximum exposure le vel, images are dev eloped
with the rotational speed of the developing
sleeve varied, then each density is read by the
Dmax sensor (PD1) on the TCSB.
The developing slee ve speed d etected when the
density has reached the reference level is
recorded as the optimum sleeve speed and the
developing is perfor med at this optimum sleeve
rotation speed.

(2) Timing

a) When the fixing temperature is lower than

50°C at power ON.

b) At the end of job after every 20,000 copies.

2-G-4

2. Signals

a. PRCB input signals

(1) Dmax SIG (TCSB to PRCB)

Output voltage of the Dmax value detection sen­sor (PD1) on the TCSB.
Reference voltage: 2.5V

(2) Dmax MONI (TCSB to PRCB)

This signal monitors the light reflected by the
drum surface (without toner).
The voltage applied to the Dmax detection LED
is corrected by γ/Dmax LED V ref so that the out­put voltage becomes 4V (calibration).
Reference voltage: 4V
<Timing>
a) Before D max correction.

(3) JAM SIG (ITCSB to PRCB)

This signal detects a jam caused by paper wrap­ping around the drum. A jam is detected when
the voltage becomes 4.0V or more.
[L]: LED ON
[H]:LED OFF

b. Output signals

(1) Dmax LED CONT (PRCB to TCSB)

This signal turns ON/OFF the D max LED.

(2) Dmax LED Vref (PRCB to TCSB)

Power supply line for PD1 LED on TSCB. The
voltage is adjusted so as the Dmax MONI s ignal
to be 4 V.

(3) JAM LED CONT (PRCB to TCSB)

This signal turns ON/OFF the JAM LED.
[L]: LED ON
[H]:LED OFF

DEVELOPING UNIT

2 UNIT EXPLANATION

2-G-5

DEVELOPING UNIT

[7] Gradation Correction Control

24VDC
24VDC

PGND

DCPS2

12VDC

5VDC

SGND

DCPS1

2 UNIT EXPLANATION

MS2 MS1

/Dmax LED Vref

M2 CONT

M2 F/R

SGND

M2 EM

M3 CONT

M3 CLK

M3 EM

DPS ANG

AGND

5VDC

LED CONT

SIG/MONI

M2

M3

DPS DRIVE A
DPS DRIVE B

DPS ANG 1
DPS ANG 2

DPSB

DPS

PRCB

Gradation correction control is performed b y the TCSB
(toner control sensor board), M2 (drum), M3 (de velop­ing), and so on. These parts are controlled by the
PRCB (printer control board).

1. Operation

The gradation characteristics of the toner density
versus exposure amount at the image forming
section (drum area) are detected to obtain a lin­ear relation between the image density on a doc­ument and the copying image density (toner
density).

(1) Method

Exposure is performed with the laser PWM var­ied in several steps, and development is per­formed at the toner transfer sleeve speed
obtained by Dmax correction.
Next, each density is read b y γ sensor (PD2) on
the TCSB to detect the gradation characteristics
of image density.
The gradation characteristics obtained here are
used as the values for correcting the laser e xpo­sure amount.

TCSB

(2) Timing

a) When the fixing temperature is lower than

50°C at power ON.

b) At the end of job after every 20,000 copies.

2. Signals

a. PRCB Input signals

(1) γ SIG/MO NI (TCSB to PRCB)

Output voltage from the γ sensor (PD2) on the
TCSB. This signal monitors the light reflected b y
the drum surface (without toner).
The voltage applied to the gradation detection
LED is corrected by γ/ Dmax LED Vref so that the
output voltage becomes 4.5V (calibration).
Reference voltage: 4.5V
<Timing>
Before gradation correct i on.

2-G-6

DEVELOPING UNIT

b. PRCB Output signals

(1) γ LED CONT, γ CONT (PRCB to TCSB)

ON/OFF control signal for gradation detection
LED.
[L]: LED ON
[H]:LED OFF

(2) γ Dmax LED Vref, Vref (PRCB to TCSB)

Power supply line to the γ LED on the TCSB.
The voltage applied to the γ LED is adjusted so
that the γ MONI signal becomes 4.5V.

[8] Dot Diamet er Correction Control

5VDC

/Dmax LED Vref

LED CONT

SIG/MONI

PRCB TCSB

Dot diameter is detected by TCSB (toner control sen­sor board) and controlled by PRCB (printer control
board).

1. Operation

Dot diameter correction is performed to prevent
the fluctuation of 1 dot laser beam in diameter
due to a soil in the writing unit or a change of
developing ability.

(1) Method

Creates several same condensation dot pattern
patches changing the laser power and reads
them with γ sensor (PD2). Uses the laser power
where the γ sensor output reaches reference
voltage as MPC.

(2) Timing

a) At the end of job after every 20,000 copies.

2 UNIT EXPLANATION

2-G-7

DEVELOPING UNIT

[9] FM2 (Develop ing Suction) Control

FM2 CONT

FM2 EM

FM2 FEM

PRCB

24VDC

PGND

DCPS2 ACDB

2 UNIT EXPLANATION

FM2 (Developing suction) is controlled by the PRCB
(printer control board) via the ACDB (A C driv e board).
When the front right or left door of this ma chine opens
or closes, MS1 (interlock 1) or MS2 (interlock 2) oper­ates to interrupt the DC power supply, stopping FM2.

1. Operation

a. ON timing

During idling: FM2 turns ON when M2 (dr um)
turns ON.
During copying: FM2 turns ON when M1 (main)
turns ON.

b. OFF timing

During idling: FM2 turns OFF when M2 turns
OFF or in the specified interval after completion
of copying.
During copying: Always ON.

2. Signals

a. PRCB input signals

(1) FM2 EM (FM2 to PRCB)

FM2 fault detection signal.
[L]: FM2 is normal.
[H]:FM2 is abnormal.

(2) FM2 FEM (ACDB to PRCB)

Signal detecting whether the 24V fuse for FM2 is
blown.
[L]: Blown fuse is not detected.
[H]:Blown fuse is detected.

FM2 DRIVE

FM2

PGND

MS2 MS1

b. PRCB output signals

(1) FM2 CONT (P RCB to ACDB)

FM2 control signal.
[L]: FM2 ON
[H]:FM2 OFF

c. A CD B output signal

(1) FM2 DRIVE (ACDB to FM2)

FM2 drive signal.
[L]: FM2 OFF
[H]:FM2 ON

2-G-8

TONER SUPPLY UNIT

[1] Composition

Toner supply
motor 1 (M11)

Toner supply
motor 2 (M15)

TONER SUPPLY UNIT

Toner car t ridge

2 UNIT EXPLANATION

Push pressure lever

Shutter

[2] Mechanisms

Mechanism Method

Toner supply Supply by screw
Toner level detectio n Piezoelectric method

*1 Toner agitation Agitator plates
*2 Toner cartridge Rotary cartridge

Toner leakage
prevention

*1 Toner agitation

Toner agitator plates are driven by the following
two motors through the gear unit:
a) Toner supply motor 1 (M11): Drives the toner

supply screw .

b) Toner supply motor 2 (M15): Drives the toner

cartridge.
The agitator plates rotate faster when toner supply
motor 1 (M11) runs than when toner supply motor 2
(M15) runs. When the two motors are running simulta­neously, the one-way clutch installed on the agitator
shaft selects toner supply motor 2 (M15).

130±30 g

Capacity: 1320 g
Toner supply shutter

The agitator plates prevent the toner from clumping
and accumulating on TLD (remaining toner detection
sensor).

Toner supply motor 1 (M11)

Toner supply motor 2 (M15)

Toner car t ridge

Agitat or plate

Toner supply screw

One way clutch

2-H-1

TONER SUPPL Y UN IT

*2 Toner cartridge

2 UNIT EXPLANATION

When the toner cartridge rotates, toner is fed to
the outlet of the cartridge through the spiral
groove on the surface of the toner cartridge.
When the outlet of the cartridge faces downward,
toner flows out of the outlet into the agitation/sup­ply section of the toner supply unit.

Outlet

A

B

C

90° rotation

B

C

A

To agitation/conveyance
block of toner supply unit

[3] Toner Level Detection Cont rol

24VDC
PGND

MS2

MS1

M15CONT

M15EM

M15CLK

5V

TLD CONT

TLD

SGND

PRCB DCPS1

Toner level detection is controlled by the TLD (toner
level detection) and the PRCB (printer control board).
When the front right or left door of this mac hine op ens
or closes, MS1 (interlock 1) or MS2 (interlock 2) oper­ates to interrupt the DC power supply to the moter,
stopping M5 (toner supply 2).

1. Operation

a. Toner level detection

A piezoelectric device is used as the TLD.
When the level of toner in the cartridge becomes
low, the toner supply signal is output to the
PRCB. As a result, a message is displayed on
the LCD connected to the OB1 (operation board

1).

b. Detection timing

The detection timing is as follows:

•Power-on

• When the front door opens or closes

• Duri ng copying

c. Toner supply to toner supply unit

When the no toner state is detected b y TLD , M15
(toner supply 2) is turned ON to supply toner from
the toner cartridge to the toner supply unit.

d. Detection of no toner state in toner cartridge

If the level of toner is not detected by TLD after
M15 has been held ON for a specified period of
time, the toner cartridge is assumed to be empty.

12VDC
SGND

DCPS2

M15

TLD

2-H-2

TONER SUPPLY UNIT

2. Signals

a. Input signal

(1) TLD (TLD to PRCB)

When the level of toner in the cartridge becomes
low, this signal goes low [L], displaying a mes­sage on the LCD connected to the OB1.

(2) M15 EM (M15 to PRCB)

M15 fault detection signal.
[L]: M15 normal
[H]:M15 Abnormal

b. Output signals

(1) TLD CONT, TSEN_CO NT (PRCB to TLD)

TLD power control signal.
The TLD is powered only when it is detecting t he
toner level.

(2) M15 CONT (PRCB to M15)

M15 control signal.
[L]: M15 ON
[H]:M15 OFF

(3) M15 CLK (PRCB to M15)

Clock signal for M15.

[4] M11 (Toner Supply 1) Control

24VDC
24VDC

M11 DRIVE A
M11 DRIVE A

M11 DRIVE B
M11 DRIVE B

PRCB

24VDC

PGND

DCPS2

M11 (Toner Supply 1) is controlled directly by PRCB
(printer control board). The toner d ensity is detected by
TCSB (toner control sensor board).

1. Operation

a. Detection of toner density

The Dmax sensor (PD1) mounted on the TCSB
detects the density of the toner control chart
developed on the drum surf ace to output the sig­nal corresponding to the detected density to th e
PRCB.

b. Toner supply

When the voltage detected by the TCSB is below
the specified value, the PRCB issues a control
signal to drive the M11. The relationship
between the paper size and toner supply time is
summarized in the following table:

Paper size Supply time (sec.)

A3
B4
F4
A4
A4R
B5
B5R
A5
A6

M11

1.14

0.86

0.86

0.57

0.57

0.43

0.43

0.29

0.22

2 UNIT EXPLANATION

2-H-3

2 UNIT EXPLANATION

CLEANING/TONER RECYCLE UNIT

[1] Composition

Blade drive motor (M14)

Blade 2

CLEANING/TONER RECYCLE UNIT

[2] Mechanisms

Mechanism Method

*1 Drum cleaning Cleaning blades

(switched automatically)

Toner collection Toner guide brush

*2 Toner recycle T oner conv ey ance b y screw

*1 Drum cleaning

T wo cleaning b lades are installed in the cleaning
section. When the blade motor (M14) rotates , the
blade release arm is pressed down. At the same
time, the cleaning blade drive shaft with two
cleaning blades 1 and 2 is turned by the wire
wound around the shaft, thereby switching
between blades 1 and 2 automatically, increas­ing the usable life of the blades.

*2 Toner collection

T oner remov ed by the cleaning b lade is collected
by the toner guide brush to be reused.

Blade 1

Toner guide brush

Vibration sheet

Toner guide shaft

2 UNIT EXPLANATION

Toner conveyance screw

Blade release arm

Blade 1

Blade 2

2-I-1

CLEANING/T O N ER RECYCLE UNIT

[3] M14 (Blade) Control

5VDC

PS30

SGND

PS31

PS30

PS31

Sensor

PS30
PS31

Blade Position

Pressing CW/

OFF OFF

CCW

Slight
pressing

ON or

OFF*

CW/
CCW

ON ON

ON OFF OFF OFF ON

Switching

M14 DRIVE 1
M14 DRIVE 2

2 UNIT EXPLANATION

PRCB

M14 (blade) is a 24V DC driven motor and drives the
cleaning blades. By M14, the cleaning blade contacts
on the drum surface slight pressing or pressing to
clean the drum surface. These two blades are auto­matically switched by M14. M14 is controlled directly
by PRCB (printer control board). Related signals are
PS30 (blade 1) and PS31 (blade 2).

1. Operation

M14 turns ON/OFF in synchronized with ON/
OFF of M2 (drum).
The blade is controlled (pressing, slight pressing,
and switching) by PS30 and PS31 detecting the
blade position, and M14 rotating forward and
backward.
The following table shows the relationship
between PS30/PS31 and blade position.

5VDC
SGND

DCPS1

24VDC
PGND

DCPS2

M14

*Note: CW/CCW indicate the M14 rotating direc-

tion for pressing, slight pressing, and
switching. The sensor logic for slight
pressing position is different b etween CW
and CCW rotation.
CCW: ON
CW: OFF

a. Blade auto switching contro l

This unit uses two blades with M14 rotating to
automatically replace blades. During automatic
blade replacement, M2 (drum), M3 (dev eloping),
developing bias, guide plate voltage, and PCL
are turned ON, toner is adhered to the drum, and
then the blade cleans it to prev ent blade peeling.
<Timing>
a) At the end of job after every 20,000 copies.
*Changeable with 25 mode DIPSW.

b. Blade setting mode

Blade setting mode is av ailable in 36 mode as a
task after blade replacement during mainte­nance. Blade setting mode adheres toner on
drum as in blade auto replacement control and
then the blade cleans toner to prevent blade
peeling.

c. Black stripe creation control

In order to improve durab ility of the blad e (stabi­lize load, prevent paper dust crushing), a black
stripe toner is adhered on drum once every five
copies and then cleaned.
*Changeable with 25 mode DIPSW.

2. Signals

a. Input signal

(1) PS30 (PS30 to PRCB)

Blade position detection signal 1.

(2) PS31 (PS31 to PRCB)

Blade position detection signal 2.

b. Output signal

(1) M14 DRIVE 1,2 (PRC B to M14)

M14 drive control signal.

2-I-2

TRAY 1/2 PAPER FEED UNIT

[1] Composition

TRAY 1/2 PAPER F EED UNIT

Side guides

Trailing edge stopper

Paper size detection VR1, 2

Paper size detectio n PS1-1, 2-1 (PS32, PS33)
Paper size detectio n PS1-2, 2-2 (PS35, PS36)

Caution: Trays 1 and 2 have the same shape

and mechanisms.

Feed roller

Paper feed roller

Double feed prevention roller

Drive pulley

Wire A

Wire B

Up drive motor 1 (M 19), 2 (M20)

[2] Mechanisms

Mechanism Method

*1 Paper lift-up Up: Paper up/down plate drive n by up/down wires

Tray loading Load from the front door side
Double feed prevention Torque limiter

*2 1st paper feed Paper feed roller

No paper detection Photosensor + Actuator

*3 Paper size detection (Universal) Width: VR

*1 Paper lift-up

a) Hoisting of up/down plate

The up/down plate is lifted up by up/down wires. When the paper tra y is loaded, the up drive motor 1 (M19),

2 (M20) rotates to wind the up/down wires around the drive pulleys and consequently the plate mov es up

and push up papers set in the tray. When the tray upper limit PS1 (PS20), 2 (PS21) detects the actuator

of the plate that has moved up, the up drive motor 1 (M19), 2 (M20) stops.

Down: F al ls down by its own weig ht

Pick up solenoid 1 (SD8), 2 (SD9)

Length: Photosensor + Actuators (two)

2 UNIT EXPLANATION

2-J-1

TRAY 1/2 PAPER FEED UNIT

2 UNIT EXPLANATION

*2 1st paper feed

b) Lowering of up/down plate

When the paper feed tray is pulled out, the
guide lever shown belo w is disengaged fr om
the rail, thus releasing the coupling gear that
transmits the drive force of the up drive motor
1 (M19), 2 (M20) to the drive pulleys. Then,
the up/down plate falls down naturally by the
weight of papers.

Coupling gear

Up drive motor
1 (M19), 2 (M20)

Tray
insertion
direction

Guide lever

To keep a constant contact pressure on the
paper by the paper f eed roller at the time of paper
pick-up, the weight of the paper feed roller itself
is used. The pick up solenoid 1 (SD8), 2 (SD9)
moves the paper feed swivel plate down so that
the paper feed roller mounted on the plate falls
down to touch the paper as well. Then, the paper
feed roller picks up a paper and feeds it toward
the paper conveyance unit. The first paper feed
solenoid moves the paper f eed swivel plate do wn
only when paper is to be fed. Otherwise, it
releases contact.

Paper feed swivel plate

Feed roller

Pick up SD
1 (SD8), 2 (SD9)

*3 Paper size det ect ion

Length: The rear guide of the tray moves , caus-

ing the paper size detection actuator to
move as well. As a result, the two paper
size detection PS1-1, 2-1 (PS32, PS33) ,
1-2, 2-2 (PS35, PS36) turn ON and/or
OFF. Thus, the paper size is automati­cally determined according to the com­bination of the ON/OFF states of these
PSs.

Width: The side guide of the tray moves, caus-

ing the side guide (front) r ack gear of t he
paper size detection arm to turn the gear
of the paper size detection VR1, 2.
Thus, the paper size is automatically
determined according to the change in
the resistance value of the VR.

Paper size detection
PS1-1, 2-1
(PS32, PS33)
1-2, 2-2
(PS35, PS36)

Rack gear

Side guide (front)

Paper size
VR gear

Actuator

Feed roller

2-J-2

[3] First Paper Feed Control

TRAY 1/2 PAPER F EED UNIT

24VDC

PGND

DCPS2

M4

PS47

PS48

PS49

PS50

The 1st paper feed from tr ay 1 or 2 tak es place as
the result of the transmission of the drive force
from M4 (paper feed) to each paper feed roller,
via MC3 (feed MC 1), MC5 (feed MC 2), and MC4
(pre-registration MC1), MC6 (pre-registration
MC 2). SD8 (pickup SD1) or SD9 (pickup SD 2)
causes the roller to pick up paper.
The above operations are controlled by the
PRCB (printer control board). Related signals
include: PS47 (paper feed 1), PS49 (paper feed

2), PS48 (paper pre-registration 1), and PS50
(paper pre-registration 2).

M4 CONT
M4 EM

M4 CLK
M4 F/R

5VDC

PS47 PS

SGND

PS48 PS

5VDC

PS49 PS

SGND

PS50 PS

24VDC

MC3 CONT

MC4 CONT

SD8 CONT

24VDC

MC5 CONT

MC6 CONT

SD9 CONT

5VDC
SGND

DCPS1

MC3

MC4

SD8

MC5

MC6

SD9

PRCB

1. Operation

a. First paper feed timing (feed MC drive)

(1) When printing of the first copy starts:

Timing that is determined by the P counter from
when copying starts

(2) When printing of the second copy starts:

When PS47 or PS49 of the first sheet of c opy is
OFF.

(3) OFF timing

After a specified count from turns ON of PS48,
and PS50.
*Changeable in 36 mode

b. Feed timing (pre-registration drive)

(1) ON timing

First sheet: When a preset time interval has

Second sheet: When a preset time interval has

(2) OFF timing

When PS47 or PS49 is turned OFF.

passed after turning ON of MC3
or MC5.

passed after turning ON of MC1
(registration).

2 UNIT EXPLANATION

2-J-3

TRAY 1/2 PAPER FEED UNIT

2. Signals

a. PRCB input signals

(1) PS47 (PS47 to PRCB)

Paper passage detection signal (tray 1).
[L]: Paper passed.
[H]:Paper not passed.

(2) PS49 (PS49 to PRCB)

Paper passage detection signal (tray 2).
[L]: Paper passed.
[H]:Paper not passed.

(3) PS48 (PS48 to PRCB)

First paper feed paper detection signal (tray 1).

2 UNIT EXPLANATION

[L]: Paper passed.
[H]:Paper not passed.

(4) PS50 (PS50 to PRCB)

First paper feed paper detection signal (tray 2).
[L]: Paper passed.
[H]:Paper not passed.

(5) PS18 (PS18 to PRCB)

Paper passage detect ion signal at the e xit of tra y
1 (for jam detection).
[L]: Paper exists.
[H]:Paper does not exist.

(6) PS53 (PS53 to PRCB)

Paper passage detect ion signal at the e xit of tra y
2 (for jam detection).
[L]: Paper exists.
[H]:Paper does not exist.

b. PRCB output signals

(1) MC3 CONT (PRCB to MC3)

MC3 drive control signal (tray 1).
[L]: MC3 ON
[H]:MC3 OFF

(2) MC5 CONT (PRCB to MC5)

MC5 drive control signal (tray 2).
[L]: MC5 ON
[H]:MC5 OFF

(3) MC4 CONT (PRCB to MC4)

MC4 drive control signal (tray 1).
[L]: MC4 ON
[H]:MC4 OFF

(4) MC6 CONT (PRCB to MC6)

MC6 drive control signal (tray 2).
[L]: MC6 ON
[H]:MC6 OFF

(5) SD8 CONT (PRCB to SD8)

SD8 drive control signal (tra y 1).
[L]: SD8 ON
[H]:SD8 OFF

(6) SD9 CONT (PRCB to SD9)

SD9 drive control signal (tra y 2).
[L]: SD9 ON
[H]:SD9 OFF

(7) M4 CLK (PRCB to M4)

Clock signal for M4.

(8) M4 F/R (PRC B to M 4 )

Rotation direction control signal for M4.

2-J-4

[4] Paper Up Drive Control

PS14

5VDC
PS14
SGND

TRAY 1/2 PAPER F EED UNIT

5VDC
SGND

DCPS1

PS20

PS34 PS34

PS15

PS21

PS37 PS37

PS20

5VDC
PS15
SGND

PS21

Papers stack ed in t he tr ay are pushed up by transmit­ting the drive force of M19 (up drive 1) or M20 (up drive

2) to the paper up/down plate in the tray via up/down
wires. M19 and M20 are controlled directly by PRCB
(printer control board). Related signals are PS20
(upper limit detection 1), PS21 (upper limit detection

2), PS34 (remaining paper detection 1) and PS37
(remaining paper detection 2). To prevent pull-out of
tray during copying operation that cause paper jam­ming, a tray loc k m echanism is implemented by PS14
(handle release 1), PS15 (handle release 2), SD5 (lock
SD1), and SD6 (lock SD2).

24VDC
PGND

DCPS2

24VDC

M19 CONT

24VDC

SD5 CONT

24VDC

M20 CONT

24VDC

SD6 CONT

M19

SD5

M20

SD6

PRCB

again, moving the paper up/down pla te upward.
The up/down plate in the tra y is lowered mechan­ically by its own weight.

b. Paper up drive timing

(1) ON timing

M19 or M20 is turned ON when loading of a tra y
is detected (by shorting wires at both ends of the
drawer connector) or when PS26 or PS27 is
turned ON.

(2) OFF timing

M19 or M20 is turned OFF when PS20 or PS21
is turned ON.

2 UNIT EXPLANATION

1. Operation

a. Paper up drive control

When tray 1 or 2 is loaded, M19 or M20 goes ON
for a fixed time, raising the paper up/down plate
in the tray. When PS20 or PS21 detects the
upper limit of paper as the paper up/down plate
in the tray goes up , it goes ON and consequently
M19 or M20 goes OFF, stopping raising the
paper up/down plate. When PS20 or PS21 goes
OFF after a paper is fed, M19 or M20 goes ON

2-J-5

TRAY 1/2 PAPER FEED UNIT

c. Remaining Paper Detection Control

The level of paper remaining in each tray is
detected according to the time that M19 or M20
requires to lift up the paper up/down plate when
the tray is set. This lift-up t ime (oper ation t ime of
M19 or M20) is recorded in the PRCB. Subse­quently, remaining paper is detected by the
paper feed counter. The detected remaining
paper level is display ed on the operation panel in
5 steps. PS34 and PS37 are used to detect the
remaining paper level when it low ers below about
10%.

d. Tray lock control

2 UNIT EXPLANATION

When the tray handle is gripped, PS14 or PS15
is turned ON. This signal then causes SD5 or
SD6 to go ON, releasing the lock.

2. Signals

a. PRCB input signals

(1) PS14 (PS14 to PRCB)

Tray drawer handle detection signal (tray 1).
[L]: Detected
[H]:Not detected

(2) PS15 (PS15 to PRCB)

Tray drawer handle detection signal (tray 2).
[L]: Detected
[H]:Not detected

(3) PS20 (PS20 to PRCB)

Paper upper limit detection signal (tray 1).
[L]: Not detected
[H]:Detected

(4) PS21 (PS21 to PRCB)

Paper upper limit detection signal (tray 2).
[L]: Not detected
[H]:Detected

(5) PS34 (PS34 to PRCB)

Remaining paper detection signal (tray 1).
[L]: Detected
[H]:Not detected

(6) PS37 (PS37 to PRCB)

Remaining paper detection signal (tray 2).
[L]: Detected
[H]:Not detected

b. PRCB output signals

(1) M19 CONT (PRCB to M19)

M19 ON/OFF control signal (tray 1).
[L]: M19 ON
[H]:M19 OFF

(2) M20 CONT (PRCB to M20)

M20 ON/OFF control signal (tray 2).
[L]: M20 ON
[H]:M20 OFF

(3) SD5 CONT (PRCB to SD5)

SD5 drive control signal (tra y 1).
[L]: SD5 ON
[H]:SD5 OFF

(4) SD6 CONT (PRCB to SD6)

SD6 drive control signal (tra y 2).
[L]: SD6 ON
[H]:SD6 OFF

2-J-6

TRAY 1/2 PAPER F EED UNIT

[5] Paper Size Dete ction Control

5VDC

PS32

SGND

PS33

VR1

5VDC

PS35

SGND

PS36

VR2

PRCB DCPS1

The paper size in tray 1/2 is detected using PS32
(paper size 1-1), PS33 (paper size 2-1), PS35 (paper
size 1-2), PS36 (paper size 2-2), paper size detection
VR1, and paper size detection VR2. Based on the
detection signals, the PRCB (printer control board)
judges the paper size.

5VDC
SGND

PS32

PS33

VR1

PS35

PS36

VR2

2. Signals

a. Input signals

(1) PS32 (PS32 to PRCB)

Paper size detection s witch ON/OFF signal (tra y

1).

(2) PS33 (PS33 to PRCB)

Paper size detection s witch ON/OFF signal (tra y

1).

(3) PS35 (PS35 to PRCB)

Paper size detection s witch ON/OFF signal (tra y

2).

(4) PS36 (PS36 to PRCB)

Paper size detection s witch ON/OFF signal (tra y

2).

(5) VR1 (VR1 to PRCB)

Paper width detection signal (tray 1).

(6) VR2 (VR2 to PRCB)

Paper width detection signal (tray 2).

2 UNIT EXPLANATION

1. Operation

The length of paper is detected using PS32,
PS33, PS35, and PS36. Variable resistors (VR1
and VR2) are installed at the bot tom of the tra y to
detect the width of paper.
The relationships between the switches and
paper sizes (lengths) are as follows :

Paper size

Switch

8.5 x 11
or less

A4R to

B5R

PS32 or PS35 OFF OFF ON ON
PS33 or PS36 OFF ON ON OFF

F4

8.5 x 14
or larger

2-J-7

TRAY 1/2 PAPER FEED UNIT

[6] No Paper Detection Control

5VDC

PS26

SGND

5VDC

PS27

SGND

PS26

PS27

2 UNIT EXPLANATION

PRCB DCPS1

5VDC
SGND

No paper in the tray is detected by PS26 (no paper 1)
and PS27 (no paper 2) which are controlled by the
PRCB (printer control board).

1. Operation

When the tray becomes empty, PS26 or PS27 is
turned ON, displaying a message on LCD via the
OB1 (operation board 1).

2. Signals

a. Input signals

(1) PS26 (PS26 to PRCB)

No paper detection signal (tray 1).
[L]: Paper does not exist in tray
[H]:Paper exists in tray

(2) PS27 (PS27 to PRCB)

No paper detection signal (tray 2).
[L]: Paper does not exist in tray
[H]:Paper exists in tray

2-J-8

TRAY 3 PAPER FEED UNIT

[1] Composition

TRAY 3 PAPER FEED UNIT

Paper feed roller

Side guide

Trailing edge stopper

Paper size detection
PS1-3 (PS38), 2-3 (PS39)

Paper size
detection VR3

Feed roller

Double feed prevention roller

Drive pulley

Front cover

Wire A

Wire B

Up drive motor 3 (M21)

[2] Mechanisms

Mechanism Method

*1 Paper lift-up Up: Paper up/down plate drive n by up/down wires

Tray loading Front loading
Double feed prevention Torque limiter

*2 1st paper feed Paper feed roller

No paper detection Photosensor + Actuator

*3 Paper size detection

(Universal)

*1 Paper lift-up

a) Hoisting of up/down plate

The up/down plate is lifted up by up/down wires . When the paper tray is loaded, the up drive motor 3 (M21)
rotates to wind the up/down wires around the drive pulleys and consequently the plate mov es up . When
the tray upper limit PS3 (PS22) detects the actuator of the plate that has moved up, the up drive motor
3 (M21) stops.

Down: F al ls down by its own weig ht

Pick up solenoid 3 (SD10)

Width: VR
Length: Photosensor + Actuators (two)

2 UNIT EXPLANATION

2-K-1

TRAY 3 PAPER FEE D U NI T

2 UNIT EXPLANATION

*2 1st paper feed

b) Lowering of up/down plate

When the paper feed tray is pulled out, the
guide lever shown belo w is disengaged fr om
the rail, thus releasing the coupling gear that
transmits the drive force of the up drive motor
3 (M21) to the drive pulleys. Then, the up/
down plate falls down mechanically by the
weight of papers.

Coupling gear

Up drive motor 3
(M21)

Tray
insertion
direction

Guide lever

To keep constant contact pressure on the paper
by the paper feed roller at the time of paper pick­up, the weight of the paper feed roller itself is
used. The pick up solenoid 3 (SD10) moves the
paper feed swivel plate down so that the paper
feed roller mounted on the plate falls down to
touch the paper as well. Then, the paper feed
roller picks up a paper and feeds it toward the
paper convey ance unit. The first paper feed sole­noid moves the paper feed swivel plate down
only when paper is to be fed. Otherwise, it
releases contact.

Paper feed swivel plate

Paper feed roller

Pick up solenoid
3 (SD10)

*1 Paper size det ect ion

Length: The rear guide of the tray moves, caus­ing the paper size detection actuator t o mov e as
well. As a result, the two paper size detection
PS1-3 (PS38), 2-3 (PS39) turn ON and/or OFF.
Thus, the paper size is automatically determined
according to the combination of the ON/OFF
states of these PSs.
Width: The side guide of the tray moves , causing
the side guide (front) rac k gear to turn the gear of
the paper size detection VR3. Thus, the paper
size is automatically determined according to the
change in the resistance value of the VR.

Paper size detection
PS1-3 (PS38),
2-3 (PS39)

Rack gear

Side guide (front)

Paper size
VR gear

Actuator

Feed roller

2-K-2

[3] First Paper Feed Control

TRAY 3 PAPER FEED UNIT

M4 CONT
M4 EM

M4

PS51

PS52

M4 CLK
M4 F/R

5VDC
PS51
SGND

PS52

PRCB

The 1st paper feed from t ray 3 tak es place as the result
of the transmission of the drive force from M4 (paper
feed) to each paper feed roller, via MC7 (feed MC3)
and MC8 (pre-registration MC3). SD10 (pick up SD3)
causes the roller to pick up paper. The above opera­tions are controlled by the PRCB (printer control
board). Related signals are PS51 (paper feed 3), and
PS52 (paper pre-registration 3).

1. Operation

a. First paper feed timing (feed MC drive)

(1) When printing of the first copy starts

Timing that is determined by the P counter from
when copying starts.

(2) When printing of the second copy starts

When PS51 turns OFF after the first paper feed
detection.

(3) OFF timing

After a specified count from turning ON of PS50.
*Changeable in 36 mode.

b. Feed timing (pre-registration clutch drive)

(1) ON timing

First sheet: When a preset time interval has

Second sheet: When a preset time interval has

(2) OFF timing

When PS19 is turned OFF.

passed after turning ON of MC7.

passed after turning ON of MC1
(registration).

24VDC
PGND

DCPS2

5VDC
SGND

DCPS1

24VDC

MC7 CONT

MC8 CONT

MC10 CONT

MC7

MC8

MC10

2. Signals

a. PRCB input signals

(1) PS51 (PS51 to PRCB)

Paper passage detection signal.
[L]: Paper passed
[H]:Paper not passed

(2) PS52 (PS52 to PRCB)

First paper feed paper detection signal.
[L]: Paper exists
[H]:Paper does not exist

b. PRCB output signals

(1) MC7 CONT (PRCB to MC7)

MC7 drive control signal.
[L]: MC7 ON
[H]:MC7 OFF

(2) MC8 CONT (PRCB to MC8)

MC8 drive control signal.
[L]: MC8 ON
[H]:MC8 OFF

(3) S D10 CONT (PRCB to SD10)

SD10 drive control signal.
[L]: SD10 ON
[H]:SD10 OFF

24VDC

PGND

2 UNIT EXPLANATION

2-K-3

TRAY 3 PAPER FEE D U NI T

[4] Paper Up Drive Control

5VDC

M21

SD7

PS16
SGND

PS22

PS40

24VDC
M21 CONT

24VDC
SD7 CONT

PRCB

PS16

PS22

PS40

2 UNIT EXPLANATION

Papers stack ed in the tr ay are pushed up by transmit­ting the drive for ce of M21 ( up drive 3) to the paper up/
down plate in the tray via up/do wn wires. MC21 is con­trolled directly by PRCB (printer control board). The
related signals are PS22 (tray upper limit 3) and PS40
(remaining paper detection 3). To prevent pull-out of
tray during copying operation that cause paper jam­ming, a tray lock mec hanism is implemented by PS16
(handle release 3) and SD7 (lock SD3).

1. Operation

a. Paper up drive control

When tray 3 is loaded, M21 goes ON for a fixed
time, raising the paper up/down plate in the tr a y.
When PS22 detects the upper limit of paper as
the paper up/down plate in the tray goes up, it
goes ON and consequently M21 goes OFF, stop­ping raising the paper up/down plate. When
PS22 goes OFF after a paper is fed, M21 goes
ON again, moving the paper up/down plate
upward. The paper up/down plate in the tray is
lowered mechanically by its own weight.

b. Paper up drive timing

(1) ON timing

M21 is turned ON when loading of a tray is
detected (by shorting wires at both ends of the
drawer connector) or when no paper is detected.

(2) OFF timing

M21 is turned OFF when PS22 is turned ON.

5VDC
SGND

DCPS1

24VDC
PGND

DCPS2

24VDC

PGND

c. Remaining Paper Detection

The level of paper remaining in each tray is
detected according to the time that M21 requires
to lift up the paper up/down plate when the tr ay is
set. This lift-up time (operation time of M21) is
recorded in the PRCB. Subsequently, remaining
paper is detected by t he paper f eed counter . The
detected remaining paper level is displayed on
the operation panel in 5 steps. PS40 is used to
detect the remaining paper level when it drops
below about 10%.

d. Tray lock control

When the tray handle is gripped, PS16 is turned
ON. This signal then causes SD7 to go ON,
releasing the lock.

2. Signals

a. PRCB input signals

(1) PS16 (PS16 to PRCB)

Tray drawer handle detection signal.
[L]: Detected
[H]:Not detected

(2) PS22 (PS22 to PRCB)

Paper upper limit detection signal.
[L]: Not det e cted
[H]:Detected

(3) PS40 (PS40 to PRCB)

Remaining paper detection signal.
[L]: Detected
[H]:Not detected

b. PRCB output signals

(1) M21 CONT (PRCB to M21)

M21 ON/OFF control signal.
[L]: M21 ON
[H]:M21 OFF

(2) SD7 CONT (PRCB to SD7)

SD7 drive control signal.
[L]: SD7 ON
[H]:SD7 OFF

2-K-4

TRAY 3 PAPER FEED UNIT

[5] Paper Size Dete ction Control

5VDC

PS38

SGND

PS39

VR3

PRCB DCPS1

The paper size in tray 3 is detected using PS38 (paper
size 1-3), PS39 (paper siz e 2- 3) and paper s ize de tec­tion VR3. Based on the detection signals, the PRCB
(printer control board) judges the paper size.

1. Operation

The length of paper is detected using PS38 and
PS39. A variable resistor (VR3) is installed at the
bottom of the tray to detect the width of paper .
The relationships between the switches and
paper sizes (lengths) are as follows :

Paper size

Switch
PS38
PS39

8.5 x 11
or less

A4R to

B5R

OFF OFF ON ON
OFF ON ON OFF

5VDC
SGND

F4

PS38

PS39

VR3

8.5 x 14
or larger

[6] No Paper De te ct ion Control

5VDC

PS28

SGND

PRCB DCPS1

No paper in the tray is detected by PS28 (no paper 3)
which is controlled by the PRCB (printer control board).

1. Operation

When the tray becomes empty, PS28 is turned
ON, displaying a message on the LCD via the
OB1 (operation board 1).

2. Signal

a. Input signals

(1) PS28 (PS 28 to PRCB)

No paper detection signal.
[L]: Paper does not exist in tray
[H]:Paper exists in tray

5VDC
SGND

PS28

2 UNIT EXPLANATION

2. Signals

a. Input signals

(1) PS38 (PS38 to PRCB)

Paper size detection switch ON/OFF signal.

(2) PS39 (PS39 to PRCB)

Paper size detection switch ON/OFF signal.

(3) VR3 (VR3 to PRCB)

Paper width detection signal.

2-K-5

2 UNIT EXPLANATION

BY-PASS TRAY

[1] Composition

BY-PASS TRAY

By-pass feed roller

By-pass paper feed roller

By-pass feed tray

By-pass double feed pre vention roller

[2] Mechanisms

Mechanism Method

*1 First paper feed Swivel roller

Pick up solenoid
(SD11)

*2 Paper lift-up Paper up/down plate

Up/down motor

(M22) (by-pass t ray)
Double feed prevention Torque limiter
No paper detection Photosensor

*3 Paper size detection Paper size detection

PS (PS55/PS56)

*1 By-pass paper feed roller

To keep constant contact pressure on the paper
by the paper f eed roller at the ti me of paper pick­up, the weight of the paper feed roller itself is
used. The pick up solenoid (SD11) moves the
paper feed swivel plate down (when the roller is
rotating) so that the paper fee d roller mounted on
the plate falls down to touch the paper as well.
Then, the paper f eed roller pick s up a pap er and
feeds it toward the paper conveyance section.
The first paper feed solenoid moves the paper
feed swivel plate down only when paper is to be
fed. Otherwise, it releases contact.

Pick up solenoid (SD11)

Paper feed
swivel plate

2 UNIT EXPLANATION

By-pass feed roller

*2 Paper lift-up

When paper is set in the bypass tray, the up/
down motor (by-pass) (M 22) drives the paper up/
down plate via gears. Paper is automatically
pushed up to the paper feed position.

Paper up/down plate

Up/down motor
(by-pass) (M22)

*3 Paper size detection

The paper size is automatically detected by the
following three sensors:

• Lateral: Paper size detection VR (VR4)

• Longitudinal: Paper siz e PS 1/2 (PS55/PS56)

2-L-1

BY-PASS TRAY

2 UNIT EXPLANATION

By-pass
tray

Paper size PS1 (PS55)

Paper size

Paper size

PS2 (PS56)
detection
VR (VR4)

[3] First Paper Feed Cont rol

24VDC

SD11 CONT

24VDC
24VDC

M6 DRIVE A

M6 DRIVE A

M6 DRIVE B
M6 DRIVE B

24VDC

PRCB

PGND

DCPS2

The 1st paper feed from the b y-pass tray takes plac e as
the result of the transmission of the drive force from M6
(loop roller) to the paper feed roller . SD11 (pick up (b y­pass tray)) mov es up and releases the paper feed roller
contacting to the paper after the roller picked up and
fed the first paper to the feed roller side to facilitate
paper feeding.
The above operations are controlled by the PRCB
(printer control board).

1. Operation

a. First paper feed operation timing

Controlled at M6 ON/OFF timings and by M6
rotation direction.

2. Signals

a. Output signals

(1) SD11 (PRCB to SD11)

SD11 drive control signal (bypass tray).
[L]: SD11 O N
[H]:SD11 OF F

(2) M6 DRIVE A, A

M6 A-phase drive control pulse signal.

(3) M6 DRIVE B, B

M6 B-phase drive control pulse signal.

(PRCB to M6)

(PRCB to M6)

24VDC

PGND

SD11

M6

2-L-2

BY-PASS TRAY

[4] Paper Up/down Control

5VDC

M22

PS23
SGND

PS43

M22 DRIVE 1
M22 DRIVE 2

PS23

PS43

PRCB

By-pass tray paper is mo ved up and dow n by transmit­ting the drive force of M22 (up/down (b y-pass)). M22 is
controlled directly by PRCB (printer control board).
Related signals are PS23 (tray upper limit (by-pass
tray)) and PS43 (tray lower limit (by-pass tray)).

1. Operation

a. Paper up/down control

M22 is turned ON a fixed time to push up paper .
When PS23 detects the upper limit of paper and
is turned ON, M22 is turned OFF to stop pushing
up paper. When paper is f ed and PS23 is turned
OFF, M22 turns ON once more to maintain the
upper limit position of the paper.

b. Paper up timing

(1) ON timing

At start of copying

(2) OFF timing

M22 is turned OFF when PS23 is turned ON.

c. Paper down timing

(1) ON timing

T urns ON when ther e is no paper or when pape r
jaming takes place.

(2) OFF timing

M22 is turned OFF when PS43 is turned ON.

5VDC
SGND

DCPS1

24VDC
PGND

DCPS2

2. Signals

a. Input signals

(1) PS23 (PS23 to PRCB)

Paper upper limit position detection signal (by­pass tray).
[L]: Detected
[H]:Not detected

(2) PS43 (PS43 to PRCB)

Paper lower limit position detection signal (by­pass tray).
[L]: Detected
[H]:Not detected

b. Output signal

(1) M22 DRIVE 1, 2 (PRCB to M22)

M22 drive control signal.

2 UNIT EXPLANATION

2-L-3