Samsung ML 7000 User manual

ML-7000 Series
ML-7050/7050N
Laser printer Contents
SERVICE Manual
1. Precautions
2. Reference Information
3. Product Information
4. Disassembly
5. Trouble Shooting
6. Exploded Views & Parts List
7.Electrical Parts List
8. Block Diagrams
9. PCB Diagrams
10. Port Thru
(Network Printer Card)

Samsung Electronics Co., Ltd. September. 1999
Printed in Korea
VERSION NO. : 0.1 P/N. JC68-00260A
ELECTRONICS

1. Precautions
1-1 Safety precautions
Read each caution carefully
1. Do not use the pinter near water or when exposed to inclement weather.
2. Do not place this printer on an unstable cart, stand or table, the product may fall, causing
serious damage to the product.
3. Slots and openings on the cabinet are provided for ventilation. To ensure reliable operation
and to protect the printer from overheation, do not block or cover any of these openings. Do
not place the printer in an enclosure unless the enclosure providesadequate ventilation.
4. Never push any kind of objects into the printer through the cabinet ventilaition slots as they
may touch dangerous hihg voltage points, create short circuits, cause a fire, or produce an
electrical shock. Never spill any kind of liquid on the printer.
5. Do not place the printer in a lacation where someone may trip on the cord.
6. Select a work surface that is lartge enough to hold the printer.
7. Operate this printer using the power source (110V, 220V, etc) indicated on the marking label.
If you are not sure of the type of power source available, consult your dealer or local power
company.
8. If you need to use an extension power cord with this printer, make sure that is uses a three-
wire grounded cord and that the total ampere ratings for all of the products using the
extension, do not exceed the extension cord ampere ration.
9. Do not allow anything to rest on th power cord or data communications cable.
10. Unplug this printer from the wall outlet before cleaning. Do not use liquid cleaners or aerosol
sprays. Use a damp cloth for cleaning.
11. Do not touch the surface of the photo-sensitive drum as marks ro scratches may impair print
quality.
12. Do not expose the drum unit to direct light for prolonged periods.
13. Use only standard papers, OHP films and approved envelopes.
Precautions
Samsung Electronics 1-1

1-2 Laser Safety Statement
The printer is certified in the U.S to conform to the requirement of DHHS 21CFR Subchapter J for Class I(1) laser
product, and elsewhere is certified as a class I laser product conforming to the requirement of IEC 825.
Class I laser product are not considered to be hazardous. The laser system and printer are designed so there is never
any human assess to laser radiation above a Class I level during normal operation, user maintenance, or prescribed
service condition
PrecautionsReference
Samsung Electronics
1-2
Caution : Never operate and service the printer with the protective cover removed from Laser Scanner
Assembly. The reflective beam, although invisible, can damage your eyes
LSU caution label is located on the LSU top side
CAUTION - INVISIBLE LASER RADIATION WHEN THIS COVER OPEN.
DO NOT OPEN COVER
VORSICHT - UNSICHTBARE SASERSTRAHLUNG, WENN ABDECKUNG GEÖFFNET.
NICHT DEM STRAHL AUSSETZEN.
ATTENTION - RAYONNEMENT LASER INVISIBLE EN CAS D’OUVERTURE, EXPOSITION DANGEREUSE
AU FAISCEAU.
ATTENZIONE - RADIAZIONE LASER INVISIBLE IN CASO DI APETURA, EVITARE L’ESPOSIZIONE AL
FASCIO.
PRECAUCION - RADIACION LASER IVISIBLE CUANDO SE ABRE, EVITAR EXPONERSE ALRAYO.
ADVARSEL - USTNLIG LASERSTRÄLNING VED ÄBNING, NÄR SIKKERHEDSBRYDERE ER UDE AF
FUNKTION, UNDGÄ UDSAETTELSE FOR STRÄLNING.
ADVARSEL - USYNLIG LASERSTRÄLNING NÄR DEKSEL ÄPNES, STIRR IKKE INN I STRÄLEN, UNNGÄ
EKSPONERING FOR STRALEN.
VARNING - OSYNLIG LASERSTRÄLNING NÄR DENNA DELÄR ÖPPNADOCH SPÄRREN ÄR
URKOPPLAD, BETRAKTA EJ STRÄLEN, STRÄLEN ÄR FARLIG.
VARO! - AVATTAESSA JA SUOJALUKITUS OHITEETTAESSA OLET ALTTINA NÄKYMÄTTÖMÄLLE
LASER SÄTELYLLE ÄLÄ KATSO SÄTEESEEN.
CLASS 1 LASER PRODUCT
LASER KLASSE 1
LUOKAN 1 LASERLAITE
APPAREIL A LASER DE CLASSE 1
TO IEC 825

2. Reference Information
2-1 Abbreviations and Acronyms
Tables 2-1 and 2-2 List abbreviations and acronyms which may be found in this service manual.
Table 2-1. Abbreviations
Abbv Definition Abbv Definition
amps amperes lb pound(s)
lin linearity
ass’y assembly lock bus lock
badac bad assess mm millimeter(s)
neg negative
bps bits per second od open drain
clk clock OSC oscillator
cm centimeter(s) OUT output
CON connector PIC picture
GND ground pos positive or position
HLDA hold acknowledge pot potential
HLDAR hold acknowledge received psynrq page synchronization request
HLDR hold request pwr power
HOR horizontal qty quantity
in inch(es) or input sw switch
INTA interrupt Acknowledge sync synchronous or
synchronization
INT Interrupt tach tachometer
INTR Interrupt request Vcc collector supply voltage(dc)
I/O Input and Output vert vertical
mpx multiplex Vp-p peak-to-peak voltage
VR variable resistor
Reference
Samsung Electronics 2-1

3. Product Information
Engine Specification
Item Descriptions Remarks
Product Information
Samsung Electronics 3-1

Controller Specification
Item Descriptions Remarks
’
Product Information
Samsung Electronics3-2

4. Disassembly
4-1 Front View
4-2 Rear View
Disassembly
Samsung Electronics 4-1
Control Panel
Cover Open
Cover Front
Cover Tray
Power Switch
Paper Level Indicator
Cover Rear
Controller
Cassette
Power Inlet

4-3 Cabinet Disassembly
4-3-1. Cover Right
Disassembly
Samsung Electronics4-2
Remove the screws and open the
Cover Rear.
In order to remove the Cover Right.
Please see the hook which locks
the cabinet to the frame, right hand
should first grab the hook and pull it
out for releasing the hook from the
frame.
Screw
Cover Rear
Cover Right
Screw
Hook

Disassembly
Samsung Electronics 4-3
The left hand should slide the
Cover Right to the backward.

4-3-2. Cover Left
Disassembly
Samsung Electronics4-4
Remove screw and open the Cover
Rear.
Please see the hook of the Cover
Left. Pull the Hook and release it
from the frame.
Slide the Cover Left to the
backward with pulling the hook out.
The Cover Left can be easily
removed.
Hook
Pull
Hook
Screw

4-3-3. Cover Front
Please see the MP tray disassembly. (4-9)
4-3-4. Cover Main
Disassembly
Samsung Electronics 4-5
Open the Cover Open.
Remove two screws.
See the hooks.
Push the hooks up and pull them
upward.
With holding Cover Main, remove
the panel wire.
Cover Open
Cover Main
Up
Screw
Cover Top
Screw

4-3-5. Cover Rear
Disassembly
Samsung Electronics4-6
Open the Cover Rear.
Detach the stripe by pushing the
stripe.
There is a hook holding the stripe.
After detaching the stripe from the
Cover Rear,
Release the Cover Rear from the
hinge.
Cover Rear
Stripe
Hinge

4-4 Video Controller board & Joint board
Disassembly
Samsung Electronics 4-7
After removing external cabinet,
see the 5 screws and you should
remove them.
The Shield ICU is important for EMI
and protection for Controller.
After removing Shield ICU, you can
see the assembled controller.
Unplug the panel cable and engine
I/F cable with care and remove the
screws from the frame.
Shield ICU
Screw
Panel Cable
Frame ICU
RAM Simm Socket
Controller Board
Engine I/F cable
Flash SIMM or
Postscript SiMM
Socket
Joint Board

Disassembly
Samsung Electronics4-8
Remove the screws which hold the
Bracket ICU to the frame and
detach controller from the frame.
You can see the Frame ICU.
Screw
Screw
Reserved for
Serial
Parallel I/F
Reserved for
Network
CPU
Connector for Network
ASIC (SPGP1)
Video Controller Board
Hyper chip

4-5 Fuser Ass’y
Disassembly
Samsung Electronics 4-9
Open the Cover Rear and see the
screws and unscrew and remove
the Cover pcb.
After removing the Cover pcb,
unplug the Thermistor connector
from the Engine Board.
Screw
Cover pcb
for engine B’d
Thermistor
connector

Disassembly
Samsung Electronics4-10
See the 4 screws which hold the
fuser ass'y to the frame. You
should unscrew and pull the fuser
out and it will be removed.
The AC connector for fuser is
designed to be directly connected
to the AC socket which is
positioned in the frame.
Screw
Screw
exit sensor
actuator
< Fuser Ass’y >
Screw
Screw

Disassembly
Samsung Electronics 4-11
When Jam happens, you can easily
remove it by pulling the Guide Rear
out like figure. In order to remove
Guide Rear, opening the Guide
Rear out like figure and pull out
hinge of Guide Rear.
Guide Rear

4-6 Bracket Motor Ass’y & Cover Open Switch Unit
Disassembly
Samsung Electronics4-12
Bracket Motor ass’y is located in
the right-upper side. Remove 7
black screws and detach the ass’y
from the frame and unplug the
motor connector from the motor.
You can see the Bracket Motor ass’y.
Motor and several gears are
assembled in one gear bracket.
Bracket Motor Ass’y
Motor
< Bracket Motor Ass’y >

Disassembly
Samsung Electronics 4-13
After removing the Bracket Motor
ass’y, you can see the Cover Open
Switch Unit.
Remove the SMPS.
Refer to SMPS & Bracket
Duplex Ass’y disassembly (4-12)
Detach two Connectors form the
SMPS.
Remove 2 screws and detach the
unit from the frame.
Cover Open Switch unit