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4. Summary of Product
This chapter describes the functions and operating principals of the main components.
4.1 Printer Components
4.1.1 Front View
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4.1.2 Rear View
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1 2 43 5 6 7
4.1.3 Control Panel
< SF-560/565P >
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5
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S
A
V
E
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F
A
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4.2 Overview of System
SF-560/SF-565P can be divided into the following main constituent parts: Main Controller, Operator’s Panel, PC
Interface, Scanner, Line Interface and Power Supply. The Main Controller uses an SPGPm processor. The
Operator’s panel; (OPE) has its own MICOM which communicates serially with a UART built into the SPGPm
processor. The Scanner uses an Image Processor chip (CIP4) to control the CIS. The Line Interface an FM336
integrated with the Main Board and communicates with the LIU at speeds up to 33.6Kbps. The Power Supply has
both the SMPS and HVPS integrated on one PBA.
4.2.1 Main Controller.
The Main Controller of the SF-560/565P consists of two ASICs (CPU, Image Processor), Scanner, Fax Modem
and Print sections. Bus Control, I/O Handling, Scanner, all motor drivers and the PC Interface function is controlled
by the CPU.
It uses the chorus2. These control the peripherals and the Image Processing.
4.2.2 Line Interface.
This part connects the set with the PSTN. The main functions of this section are Line Interface, Line Monitoring,
and connection to an external phone or TAD using the built in EXT connector..
4.2.3 Print Engine.
The Print Engine consists of the following sections: Frame, Paper Feed, Image Transfer, Imaging Unit, Toner
Cartridge, Fuser, High Voltage Supply and Scanner. The set uses an Electro Photographic process using the LSU
to develop a latent image on the OPC drum. The Toner process is a single part diamagnetic process. Copy and
Transfer processes use a CIS Module.
4.2.4 Scanner.
The scanner is designed around a 200dpi CIS module. The CIS scanning width is maximum 216mm,
effective width is 208mm. The SF560 operates at 200lpi, the SF565 operates at 300 lpi.
4.2.5 Summary of Main Unit
- Main Board
This is an integral unit having the Engine and Video control on a single PBA. It controls the Electrophotographic
Process to take the image from the PC Interface and generate the Video Data for the LSU. It also manages the
transfer of that image onto paper and the fusing of the image. The main PBA unit consists of the following circuits:
Motor (Paper Feed and Exit) Driver, the Clutch driver, Pre-transfer Lamp Driver, the Fuser Driver and the Fan
Driver. The signals from the Paper Feed Sensor, the Paper Empty Sensor, MPsensor and Exit Sensor are input to
the Main Board from the SMPS/HVPS PBA.
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- SMPS Board & HVPS Board
These are integrated into a singe PBA. The Power Supply uses the 110VAC/220VAC supply voltage to
generate the DC Voltages used by the system. The SMPS has 3 output channels (+5V, +12V, +24V, +24VS) and
supplies the Main Board and the OPE Board.
The HVPS creates the high voltages (THV/MHV/Supply/Dev) used for the electrophotographic process. The high
voltage is created from the 24VS line from the SMPS. High Voltage output is supplied to the Toner, the OPC
Cartridge and the Transfer Roller.
- OPE Board
The Operation Panel is driven by its own internal program using the OPE MICOM chip separate from the Main
Board processor. Data is transferred using the UARTPort in the Main Controller serially. This unit
consists of the MICOM, the Key Pad Matrix and the LCD.
- Toner Cartridge
The Toner Cartridge consists of integrated Exposure and Developer units. The Exposure Unit consists of the OPC
Drum and the Charge Roller, and the Developer Unit consists of the toner particles and its tank, the Supply Roller
and the Developer Roller.
- LSU (Laser Scanner Unit)
This is the core of the laser printer. It converts the video data received from the computer into an electrostatic
latent image on the surface of the OPC drum. This is achieved by controlling the laser beam and exposing the surface of the OPC drum to the laser light. Arotating polygon mirror reflects the laser light onto the OPC and each
side of the mirror is one scan line. The OPC drum turns as the paper feeds to scan the image down the page.
The /HSYNC signal is created when the laser beam from LSU reaches the end of the polygon mirror and this signal is sent to the controller. The controller detects the /HSYNC signal to adjust the vertical line of the image on
paper. In other words after the /HSYNC signal is detected the image data is sent to the LSU to adjust the left margin on the paper.
- Toner Transfer
Toner is transferred from the OPC drum onto the paper using a PTL (Pre-transfer Lamp) and a transfer roller. The
PTL shines light onto the OPC, this reduces the electrical charge on the surface of the OPC
surface and improves the efficiency of the transfer.
The transfer roller transfers toner from the OPC drum to the paper.
Life span: Print over 100,000 sheets (at 15~30ºC)
- Fuser
This consists of a heat lamp, heat roller, pressure roller, thermistor and thermostat. By use of heat and pressure
toner is caused to melt and adhere to the paper surface in order to complete the printing process.
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4.3 System Layout
4.3.1 Feeding section
There is a universal cassette which automatically loads paper and the manual feed which supplies paper
single sheet at a time. The cassette has a friction pad which separates paper to ensure single sheet
feeding, and it has a sensor, which checks when the paper tray is empty.
- Feeding Method: Universal Cassette Type
- Feeding Standard: Center Loading
- Feeding Capacity: Cassette-250 sheets (75g/m2, 20lb paper standard)
Manual 1 sheet (Paper, OHP, Envelop, etc.)
- Paper detecting sensor: Photo sensor
- Paper size sensor: None
4.3.2 Transfer Ass’y
This consists of the PTL (pre-transfer lamp) and the Transfer Roller. The PTL shines a light onto the OPC
drum. This lowers the charge on the drum’s surface and improves transfer efficiency.
The transfer roller transfers toner from the OPC drum surface to the paper.
- Life expectancy: Over 60,000 sheets (at 15~30°C)
4.3.3 Driver Ass’y
- Gear driven power unit. The motor supplies power to the paper feed unit, the fuser unit, and the toner
cartridge.
4.3.4 Fixing Part(Fuser)
- The fuser consists of the Heat Lamp, Heat Roller, Pressure Roller, Thermistor, and Thermostat. It fixes
toner to the paper using pressure and heat to complete the printing job.
4.3.4.1 Temperature-Intercepting Device (Thermostat)
The thermostat is a temperature sensing device, which cuts off the power to the heat lamp to prevent
overheating fire when the heat lamp or heat roller overheats.
4.3.4.2 Temperature Detecting Sensor (Thermistor)
The Thermistor detects the surface temperature of the heat roller, this information is sent to the main
processor which uses this information to regulate the temperature of the heat roller.
4.3.4.3 Heat Roller
The surface of the Heat Roller is heated by the Heat Lamp. As the paper passes between the Heat and
Pressure rollers the toner is melted and fixed permanently to the paper. The surface of the roller is coated
with Teflon. This ensures that toner does not adhere to the roller surface.
4.3.4.4 Pressure roller
The Pressure Roller mounted under the heat roller, it is made of a silicon resin, and the surface of the roller
is coated with Teflon. This ensures that toner does not adhere to the roller surface.
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4.3.4.5 Safety Features
• To prevent overheating
- 1st protection device: Hardware cuts off when overheated
- 2nd protection device: Software cuts off when overheated
- 3rd protection device: Thermostat cuts off mains power to the lamp.
• Safety device
- Fuser power is cut off when the front cover is opened
- LSU power is cut off when the front cover is opened
- The temperature of the fuser cover's surface is maintained at less than 80ºC to protect the user and a
caution label is attached where the customer can see it easily when the rear cover is opened.
4.3.5 Scanner
• Scan Image Controller
1.Minimum Scan Line Time : 1.23ms
2.Scan Resolution : Color (Max 600 DPI)
3.Scan Width : 208mm
4.Function
- White Shading Correction
- Gamma Correction
- CIS Interface
- 256 Gray Scale
• CIS Driver Circuit
- CIS Max Frequency : 0.5MHz
- CIS Line Time : 5ms
- White Data Output Voltage : Max 1.2V
• Tx Driver Circuit
- Tx Motor Speed : Max 2200pps
- Motor Driver : STA471A
- Voltage : 24V DC
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4.3.6 LSU (Laser Scanner Unit)
This is the core of the laser printer. It converts the video data received from the computer into an electrostatic latent image on the surface of the OPC drum. This is achieved by controlling the laser beam and exposing the surface of the OPC drum to the laser light. Arotating polygon mirror reflects the laser light onto the
OPC and each side of the mirror is one scan line. The OPC drum turns as the paper feeds to scan the
image down the page.
The /HSYNC signal is created when the laser beam from LSU reaches the end of the polygon mirror and
this signal is sent to the controller. The controller detects the /HSYNC signal to adjust the vertical line of the
image on paper. In other words after the /HSYNC signal is detected the image data is sent to the LSU to
adjust the left margin on the paper.
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4.3.7 Toner Cartridge
The toner cartridge is an integral unit containing the OPC unit and toner unit. The OPC unit consists of the
OPC drum and charging roller, and the toner cartridge unit consists of the toner, supply roller, developing
roller, and blade (Doctor blade)
- Developing Method: Non magnetic 1 element contacting method
- Toner: Non magnetic 1 element shatter type toner
- The life span of toner: 3,000 sheets (IDC Pattern/A4 standard)
- Toner remaining amount detecting sensor: Yes
- OPC Cleaning: Electrostatic process
- Management of waste toner: Collect the toner using a Cleaning Blade
- OPC Drum protecting Shutter: Yes
- Classifying device for toner cartridge: ID is classified by interruption of the frame channel
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4.4 Main PBA(SPL Model)
The Engine Board and Controller Board have been integrated into a single PBA. This consists of the CPU,
printer scanner and line control functions. The CPU functions as the bus controller, I/O handler, motor driver
and PC inter-face. The main board sends the Current Image Video data to the LSU and manages the
Electrophotographic printing process. Circuits on the PBA drive include the main motor (paper feed,
cartridge, fuser), clutch driver, pre-transfer lamp driver, heat-lamp driver, CIS driver, scan motor driver,
modem and fan driver.
The signals from the paper feed jam sensor and paper empty sensor are inputted to the main board from
the power supply PBA..
CN7
OSC3
(28.224MHz)
CN2
CN3
CN4
CN8
CN10
OSCI(14,7456MHz)
CN5CN6CN9
CN13
OSC2
(0.0327MHz)
CN11CN14CN15CN12 OSC4
(10MHz)
FLASH
MEMORY
MODEM
EXPANSION I/O
(HCT273)
Battery
SDRAM
STA471
(SCAN MOTOR DRIVE I/C)
SUPER1284
BUFFER(INVERTER)
74HCTO 4M
MODEM CLOCK
MOTOR DIRVE IC
(A3 977 SLP)
ASIC
74LVX161284
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4.4.1 ASIC (Chorus2)
Samsung’s S3C46Q0X 16/32-bit RISC micro controller is designed to provide a cost-effective, low power,
small die size and high performance micro-controller solution for MFP.
The S3C46Q0X is developed using ARM7TDMI core, 0.18(m CMOS standard cell, and memory cell.
•Main function block
• 1.8V internal, 3.3V external (I/O boundary) microprocessor with 4KByte Cache
• Image Processor
• On-chip clock generator with PLL
• Memory & External Bank Control
• DMA Control (5-channel)
• Interrupt Control
• 2-port USB Host /1- port USB Device (ver 1.1) Interface Control
• Parallel Port Interface Control
• UART (2 Channel)
• Synchronous Serial Interface Control
• Timer (4 Channel)
• Watch Dog Timer
• Power control: Normal, Slow, Idle, Stop and SL_IDLE mode
• A/D Converter (10-bit, 2 Channel)
• General I/O Port Control
• Print Head Control
• Carrier Motor Control
• Paper Motor Control
• Tone Generator
• RTC with calendar function
• S/W Assistant function( Rotator )
4.4.2 Flash Memory
This stores the system program. Firmware upgrade is achieved by downloading from the new image using the PC
Interface.
• Capacity : 0.5 M Byte
• Access Time : 70 nsec
4.4.3 SDRAM
This is used as a buffer, system working memory area, etc. while printing and scanning. This memory is also used to
store faxes waiting to be sent or waiting to be printed.
• Access Time : 60 nsec
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4.4.4 Sensor input circuit
1) Paper Empty Sensor
The Paper Empty sensor (Photo Interrupter) on the SMPS/HVPS PBA is monitored by the CPU on
signal(nP_EMPTY, CN3-Pin 1). When the cassette is empty the printer displays a message on the LCD
panel.
2) MP Sensing
Presence of paper in the MP tray is detected by operation of the MP Sensor (Photo Interrupter) on the
SMPS/HVPS PBA. The CPU monitors signal(MP_EMPTY, CN3-Pin 13) to recognize paper in the MP,
and paper is fed from MP if there is paper present.
3) Paper Feed Sensor, (Toner Cartridge Sensor)
When paper passes the actuator on the feed sensor, it is detected by the Photo interrupter.
signal(nP_FEED, CN3-Pin 2) monitored by the CPU and this signal starts the process of creating the
image after certain delay time If the feed sensor is not detected within 1 sec. after paper is fed, a paper
Jam0 occurs. (Displayed on the LCD panel).
When a toner cartridge is inserted it also operates the Paper Feed sensor. A message is displayed on the
LCD if no cartridge is detected.
4) Paper Exit Sensor
This detects that paper exits cleanly from the Machine using an exit sensor on the engine board and
actuator on the frame. The monitors signal(P_EXIT, CN3-Pin 26) and detects the on/off time of the exit
sensor and if jam status is detected then JAM2 is displayed the on the LCD panel.
5) Cover Open Senser
The Cover open sensor actuator is located on the front cover and the senor is in the main frame. When the
front cover is opened the +24VS to the DC fan, solenoid, main motor, polygon motor part of LSU, HVPS that
are cut off. The CPU monitors
signal(COVER_OPEN)
to recognize when the cover is opened.
6) DC FAN / SOLENOID Driving
It is driven by a transistor and controlled by signal(FAN, CN3-Pin 24) bit of the CPU.
When it is high the fan is activated by turning on the TR, and it is off when the sleep mode is selected.
There are two solenoids and these are driven by the Paper Pick-up and MP signals. The drive time is
300ms. The diode protects the driving TR from the Back-EMF pulse which is generated when the
solenoid is de-energized.
7) Motor Driving
The motor driving circuit is activated when the Driver IC is enabled. An A3977 (Motor driver IC) is used in
this case. The resistance Rs value of sensing and the voltage value of the V reference can be changed
by the motor driving voltage value.
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4.5 SMPS & HVPS
The SMPS and HVPS are on one integrated board.
The SMPS supplies the DC power to the system. It takes either 110V or 220V and outputs the +5V,
-5V/0.5A, 12V and 24V supplies to the main and ADF PBAs.
The HVPS creates the high voltage of THV/MHV/Supply/Dev and supplies it to the toner cartridge. The CPU is
used to modify some of these voltage settings to provide the ideal voltages to create the image.
The HVPS part uses the 24V and outputs the high voltage for THV/MHV/BIAS and the outputted high voltage is
supplied to the toner, OPC cartridge and transfer roller.
MAIN PBA CON.
CN3
(FAN CON.)
CN1
(H/L CON.)
F101
250V L2A
EXIT SENSOR
MHV
OPC
DEV
SUPPLY
THV
COVER OPEN SWITCH
MANUAL SENSOR
FEED SENSOR
PAPER-EMPTY SENSOR
F1
110V : 125V/8A
220V : 250V T 5A H
F2
110V : 125V/3A
220V : 250V 2A H
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4.5.1 HVPS(High Voltage Power Supply)
1) Transfer High Voltage (THV+)
- Function : It is this voltage that transfers toner from the OPC Drum to the paper.
- Output voltage : +1300V DC±20V
- Error : IF THV (+) is not present, low density printing occurs due to toner on the OPC Drum not being
transferred to the paper. It is possible that waste toner over-flow can occur if this condition persists.
Ghost images may appear which repeat at 76mm intervals.
2) Charge Voltage (MHV)
- Function : It is this voltage that charges the surface of the OPC to -900V ~ -1000V.
- Output voltage : -1550V DC ± 50V
- Error : IF MHV is not present toner then since the OPC drum surface has no charge toner is attracted to
the whole OPC surface. Ablack page is printed out when this happens.
3)Cleaning Voltage (THV-)
- Function : It removes toner contamination from the rear side of the paper by sending (-) polarity to the
transfer roller forcing toner to transfer back to the to OPC drum.
- Output Voltage : +300V/-150V
- Error : Smudges and toner contamination on the reverse side of the printed page.
4) Developing Voltage (DEV)
- Function: It is this voltage that develops toner with on to the section of the OPC drum surface exposed
by the LSU
(Laser Scanning Unit).
* When printing the exposed voltage on the OPC is -180V, unexposed is -900~-1000V, and the exposing
voltage on the DEV is -430V. Therefore toner with (-) polarity is developed onto an exposed
section of the OPC.
- Output voltage: -430V DC ± 20V
- Error: a) If DEV is GND, print density gets extremely low.
b) When DEV is floating due to poor connection between the frame and cartridge contacts etc.,
print density gets extremely high.
5) Supply Voltage (SUP)
- Function: It is this voltage that supplies toner to the developing roller.
- Output voltage: : -630V DC ± 50V (Use ZENER, DEV Gear)
- Error: a) When SUP is GND print density gets extremely low.
b) If SUP is floating due to poor connection between the frame and cartridge contacts etc. density
gets extremely low such that it is hard to see toner with the eyes
6) OPC Ground ZENER Voltage
- Function: It is this voltage that prevents image contamination under low temperature and low humidity
environment conditions.
- When a set prints without an output voltage, -130V DC ± 15V is maintained on OPC ground. (-103V
ZENER diode is connected to OPC ground)
- Error type:
a) When the ZENER diode is - 0V there is no serious image problem in general environment,
but in low temperature and low humidity environments it is possible that contamination
can occur on the entire image
b) When the ZENER diode is disconnected a blank page is printed out. (It is the same when
a ZENER diode is disconnected from OPC ground.)
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4.5.2 SMPS (Switching Mode Power Supply)
ItThis is the power source for the whole system. It is an independent module so that it is possible to use it for
common use. It is mounted at the bottom of the set.
It consists of the SMPS section, which supplies the DC power to drive the system, and the AC heater control
part, which supplies the power to the fuser. The SMPS has four output channels ((+5V, -5V, +12V, +12Vand
+24Vs).
There are three kinds of power, 120V exclusive (America), 220V exclusive (Europe), and 220V for China
(nations with unstable power supply).
1) AC Input
- Inputting rated voltage : AC 220V ~ 240V AC 100~127V
- Inputting voltage fluctuating range : AC 198V ~ 264V AC 90V ~ 135V
- Rated frequency : 50/60 Hz
- Frequency fluctuating range : 47 ~ 63 Hz
- Inputting Current : Under 4.0Arms/2.0Arms
2) Rated Power Output
3) Consumption Power
4) Length of Power Cord :
1830 ± 50mm
5) Power Switch :
Fitted
NO Item CH1 CH2 CH3 CH4
1 Channel name +5V -5V +24.0V +24.0VS
2 CONNECTOR PIN CON 2 CON2 CON2 CON2
3.3V PIN: 3, 4 -5V PIN : 7 24V PIN: 1 1, 12 24V PIN: 13, 16
GND PIN: 5, 6 GND PIN: 8 GND : 9, 10 GND : 18
3 Rated outputting voltage +5V ± 5% -5V ± 5% +24V ± 10% +24V ±10%
(4.75 ~ 5.25V) (-4.75~-5.25V) (21.6 ~ 26.4V) (21.6 ~ 26.4V)
4 Rated outputting current 1.5 A 0.5A 1.5 A 1.0 A
5 Ripple noise voltage 150mVp-p 150mVp-p 500mVp-p 500mVp-p
6 Maximum output 7.5W 0.6W 36.0W 24.0W
NO Item CH1 CH2 CH3 CH4 System
(+5V) (+12V) (+24V) (+24VS)
1 Stand-By 1.0 A 0.05A 1.0 A 0.5 A AVG : 60 Wh : 220V
A VG : 75 Wh : 110V
2 Operating 1.5 A 0.5A 1.5 A 1.0 A AVG : 320 Wh
3 Sleep-Mode 0.3A 0.0A 0.0A 0.06A AVG : 15 Wh
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6) Feature
- Insulating resistance : over 50MΩ (at DC500V)
- Insulating revisiting pressure : Must be no problem within 1min. (at 1500Vzc, 10mA)
- Leaking current : under 3.5mA
- Running current : under 40A peak (at 25°c, Cold start) Under 60A peak (in other conditions)
- Rising Time : Within 2Sec
- Falling Time : Over 20ms
- Surge : Ring Wave 6KV-500A (Normal, Common)
7) Environment Condition
- Operating temperature range : 0°c ~ 40°c
- Storage temperature range : -25°c ~ 85°c
- Storage humidity range : 30% ~ 90% RH
- Operating atmospheric pressure range : 1
8) EMI Requirement :
CISPR ,FCC, CE, MIC, C-Tick,
9) Safty Requrement
- IEC950, C-UL, TUV,Semko,iK,CB, CCC, EPA,
4.5.3 Fuser AC Power Control
The Fuser (HEAT LAMP) is heated using AC power. The AC power is controlled by a Triac (THY1), a
semiconductor switch. 'On/Off control' is achieved when the gate of the Triac is turned on/off by a Photo
triac (PC1), this is an insulting part.
In the other words the AC control part is a passive circuit. It turns the heat lamp on/off by taking a signal
from the engine control section. When the 'HEATER ON' signal is activated by the engine the LED of PC1
(Photo Triac) flashes. The flashing light causes the Triac (PC1) to switch and a voltage is supplied to the
gate of Triac THY1.
As a result AC current flows in the heat lamp, and heat is produced.
On the other hand, when the signal is off, PC1 is off, the voltage is cut off at the gate of Triac THY1, this
Triac is therefore off, and thus the heat lamp is turned off.
1) Triac (THY1) feature
- 12A,600V SWITCHING
2) Phototriac Coupler (PC3)
- Turn On If Current : 15mA~ 50mA(Design: 16mA)
- High Repetive Peak Off State Voltage : Min 600V
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4.6 Engine F/W
4.6.1 Feeding
If feeding from the cassette the drive of the pickup roller is controlled by controlling the pick-up solenoid.
The on/off of the solenoid is controlled by controlling the general output port or the external output port. If
feeding from the manual feeder the set decides to feed the paper according to the operation of the manual
sensor, and by driving the main motor, insert the paper in front of the feed sensor. When paper moves the
occurrence of a paper jam is judged as below.
4.6.1.1 Jam 0 – Jam in Feed area
• After a page was picked up, paper did not enter the unit due to a paper misfeed.
• After a page was picked up, paper entered but it did not reach the feed sensor in certain time due to slip, etc.
• After a page was picked up, if the feed sensor is not on try to pick up again. After retrying if the feed
sensor is still not on after certain time, it is Jam 0.
- this indicates that the leading edge of the paper doesn't pass the feed sensor within a certain time.
• Even though the paper reaches the feed sensor, the feed sensor does not turn on.
- this indicates that the leading edge of the paper already passed the feed sensor or that the sensor is
fauty.
4.6.1.2 Jam 1 – Jam inside the print engine
• After the leading edge of the paper passes the feed sensor, the trailing edge of the paper does not pass
the feed sensor within certain time. (During this time the feed sensor cannot be Off)
• After the leading edge of the paper passes the feed sensor, the paper does not reach the exit sensor within certain time. (The exit sensor cannot be On during this time)
- There is already paper between the feed sensor and the exit sensor.
4.6.1.3 Jam 2 – Jam in the Exit area
• After the trailing edge of the paper passes the feed sensor the trailing edge of the paper does not pass
the exit sensor within certain time.
4.6.2 Drive
The main motor drives the paper feed, developing unit and the Fuser It is driven by software which controls
the acceleration, constant speed and deceleration profiles. The Motor is managed with an A3977 driver IC
and controlled by step and enable signals from the CPU.
4.6.3 Transfer
The charging voltage, developing voltage and the transfer voltage are controlled by PWM (Pulse Width
Modulation). Each output voltage is changeable according to the PWM duty cycle. The transfer voltage
used when the paper passes the transfer roller is decided by environment recognition. The resistance value
of the transfer roller changes due to the surrounding environment in the room or within the set, this change
in resistance in turn changes the value of the voltage due to loading. This voltage is fed back into the set
through the A/D converter. Based on this fed back value the PWM cycle is changed to maintain the
required transfer voltage
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4.6.4 Fusing
The temperature of the heat roller's surface is detected according to the resistance value of the thermistor.
The thermistor resistance is measured using the A/D converter and thus the CPU can determine the
temperature of the heat roller. The AC power is controlled by comparing the target temperature to the value
from the thermistor. If the value from the thermistor is out of the controlling range while controlling the fusing
process, the error stated in the table occurs. (For the domestic model, the Q-PID method has been applied.)
4.6.4.1 Error Type
4.6.5 LSU
The LSU consists of the LD (Laser Diode) and the polygon motor control. When the printing signal occurs,
the LD is turned on and the polygon motor is enabled. When the light sensor detects the beam, Hsync occurs.
When the polygon motor speed becomes a normal, LReady occurs. If these two conditions are satisfied, the
status bit of the LSU controller register becomes 1 ant the LSU is judged to be ready. If the two conditions
are not satisfied, the error shown in the table below occurs.
Error Description
Open heat error When warming up, it has been lower than 68 °C over 25 sec
Lower heat error • Standby:
It has been lower than 100°C over 25 sec
• Printing:
- 2 consecutive pages: it has been lower than 145°C over 5 sec
- 3 consecutive page; it has been 40°C lower than the fixed fusing temperature over 4 seconds.
Over heat error It have been higher than 220°C over 3 seconds
Error Description
Polygon motor error When the polygon motor’s speed doesn’t become a normal
Hsync error The polygon motor’s speed is normal, but the Hsync signal is not created.
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4.7 LIU PBA
The LIU board is the Line interface unit, it is a circuit for interfacing a telephone line with a modem. The circuit consists of
a matching transfer to conform to the impedance of the receiving telephone line and a circuit to conform to the impedance
of a modem.
Also, there is a ring detect circuit to detect a ring signal from the switchboard and a surge absorber to protect against
lighting strike surges on the incoming line.
Line-matching
Transformer
Surge Absorber
CN1(LIU)
Tel-Line
Jack
Ring Detect Circuit
(PC814)
External-Phone matching
Transformer
External-Line
Jack
CN2(Hook)
External Phone
Detect Circuit
(PC814)
4.8 OPE PBA
The OPE board consists of various function keys and an LCD to display set status and operator messages.
A MICOM (HOLTEC HT48R50) and drives the LEDs and LCD. Communication between the OPE and the
CPU on the main board is serial (related signals are /Reset, TXD, and RXD).
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