Panasonic KX FLB758RU User Manual

							The correspondence readings between temperature measured by thermistor and HEX readings
Temperature(°C)HEX readingTemperature( °C)HEX readingTemperature( °C)HEX reading
03F843C16820
13F853B16920
23F863B1701F
33F873B1711F
43F883B1721F
53F893A1731E
63F903A1741E
73F913A1751D
83F923A1761D
93F933A1771D
103F94391781C
113F95391791C
123F96391801B
133F97391811B
143F98381821B
153F99381831A
163F100381841A
173F101381851A
183F1023718619
193F1033718719
203F1043718818
213F1053618918
223F1063619018
233F1073619117
243F1083619217
253F1093519317
263F1103519416
273F1113519516
283F1123419615
293F1133419715
303F1143419815
313F1153419914
323F1163320014
333F1173320114
343F1183320213
353F1193220313
363F1203220413
373F1213220512
383F1223120612
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							Temperature(°C)HEX readingTemperature( °C)HEX readingTemperature( °C)HEX reading
393F1233120712
403F1243120811
413F1253020911
423F1263021011
433F1273021110
443F1282F21210
453F1292F2130F
463F1302F2140F
473F1312E2150F
483F1322E2160E
493F1332D2170E
503F1342D2180E
513F1352D2190E
523F1362C2200D
533F1372C2210D
543F1382C2220D
553F1392B2230C
563F1402B2240C
573F1412B2250C
583F1422A2260B
593F1432A2270B
603F144292280B
613F145292290A
623F146292300A
633F147282310A
643F148282320A
653F1492823309
663F1502723409
673F1512723509
683E1522623608
693E1532623708
703E1542623808
713E1552523908
723E1562524007
733E1572424107
743D1582424207
753D1592424307
763D1602324406
773D1612324506
783D1622224606
793D1632224705
803C1642224805
813C1652124905
823C1662125020
833C16721
Note:
The value is displayed on LCD at TEST FUNCTIONS(P.74) [#815].
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							7.14. POWER SUPPLY BOARD SECTION
This power supply board uses the switching regulator method.
Input
Circuit
AC
Input
Surge
absorber
circuit G
H
5V
24V
Kick-on
Voltage
Circuit
E
IC101
F
PGND
DGND
HTRON
Control
Circuit
R110
R111
Converter
Circuit
C
D
5V
Output
Circuit
24V
Output
Circuit+-Rectifier
CircuitA
B
C106
Error Detecting
Circuit
Surge
absorber
circuit
O.C.L
Over voltage Q101
A-B Voltage Wave Form
C-D Voltage Wave Form
E-F
G-H
 Voltage Wave Form
0
0 0
Block Diagram
CN101
CN102
T101
PC101 IC202
Triac
SCR101
Heat LampPhot Triac
Coupler PC102
[Input Circuit] The input current goes into the input rectifier circuit through the filter circuit. The filter circuit decreases the noise voltage and
the noise electric field strength.
[Rectifier Circuit] The input current is rectified by D101~ D104 and charges C106 to make DC voltage. Then it supplie s power to the converter
circuit.
[Kick-on voltage circuit] Bias is applied to the Q101 gate via this circuit when the AC power is turned on and Q101 begins operating.
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							The followin g is an overview of how the power supply unit is controlled.
The control method of this power supply unit is pulse width modulation.
W hen Q
1is ON, the energy is charged in the transfer primary coil according to E1. W hen Q1is OFF, the energy is output from
the secondary transfer as follows.
L → D
1→Load →L
Then the power is supplie d to the Load. W hen Q
1is ON, power is not output from the secondary side. The output voltage is fed
back in the control IC according to the error amp rectifier. Then depend ing on how T
ONis controlled, stabilization occurs. Also,
when the current load becomes too large, in order to decrease the voltage output, the increase in
is controlled and the output
voltage is stabilized.
Therefo re, basically the timing: Ton/To ff of Q1 controls the output voltage.
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							[Surge Absorber Circuit]This circuit is for absorbing surge voltage generated by the transformer.
[Control Circuit and Detecting Circuit] The control circuit amplifie s the output with increased voltage detected in the error detecting circuit. Then it drives the main
transistor.
In this power supply, the duty ratio is defined by changin g the ON period of the main transistor.
This is shown as follows.
W hen the output voltage of the 24V circuit increases, the current of the photo coupler PC101 increases, the pulse width of the
output control IC becomes narrower and the ON period of Q101 becomes shorter.
[Over Current Limiter (O.C.L)] The highest drain current (Q101) is limited by a limiter circuit (IC101) of 24V. The 24V output is limited by this circuit.
[Over Voltage Circuit] If the 24V output increases because the error detecting circuit or control circuit is broken, IC101 will recognize this signal and
output becomes 0V.
Dummy load method (to quickly check the power supply output) Refer to POWER SUPPL Y BOARD SECTION,] (P.155).
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							8 REFERENCE MATERIALS DATA
8.1. PRINTING OPERATION PRINCIPLE
8.1.1. PROCESS CHART AND PROCESS BIAS
8.1.2. CHARGING
Charging is the stage that keeps the surface of the sensitive drum a fixed electric potential. The sensitive drum is the Organic Photo
Conduc tor (OPC), which is a electric conductive cylinde r whose surface is covered with the Charge Generation Layer (CGL) and
Charge Transfe r Layer (CTL).
W hen the charging bias (DC -1.2 Kiev) is added and the minus charge is supplie d to the charge brush while charging, the whole
surface potential of the drum is -800V.
Charging Part
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							8.1.3. EXPOSING
W hen the drum which is charged with the fixed electric charge is irradiated by the laser beam, the plus charge and minus charge
are generated at the Charge Generation Layer. Passing through the Charge Transfe r Layer which conducts the plus charge, the
minus-charged drum´s surface is neutralized to be skipped. Then the minus charge goes to the ground from the electric conductive
cylinde r. Consequently the charge of the part which is not expose d remains as it is, and the electric potential of the scanned part
changes.
At that time an invisible image is created on the drum.
Exposing Part
8.1.4. LASER SCANNING UNIT LOCATIONS
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							8.1.5. DEVELOPING AND TRANSCRIPTION
The develop ing is the stage that the OPC drum with an invisible image is changed to visible by the toner. The develop er consists
of mixing paddle , toner supply roller, develop ing roller, develop ing blade and OPC drum. The bias voltage is added to the
develop ing roller (DC -180V) and toner supply roller (DC -350V). Firstly the toner is mixed up in the mixing paddle and minus-
charged by triboelectricity, then led to the toner supply roller. Second ly the potential differen ce causes to send the toner to the
develop ing roller from the toner supply roller. The supplie d toner to the develop ing roller is kept to a certain layer thickness by the
develop ing blade and also it is charged by triboelectricity. Consequently the toner is transferred to the surface of the expose d OPC
drum by the potential differen ce between the develop ing roller and OPC drum´s surface.
The transcription is the stage that the created image on the OPC drum is transferred to the paper. W hen the transfer roller is plus-
charged with the image, the minus-charged toner particles are gathered on the surface of the drum and transferred to the paper.
Developing and Transcription Part
The values of develop ing bias and supply bias are differen t from the ones described in the Service Manua l for FL501.
The biases output from the unit of FL501,FLM55 1 and FLB751 (FLB75 0) have the same voltage. However, the develop ing device
of FA78X(FA78A ) converts the develop ing and supply biases inside the develop ing device to improve the image quality.
FA77X(FA77A) developing deviceFA78X(FA78A) developing device
Developing bias-350V-180V
Supply bias-550V-350V
Inside voltage conversion circuit of the develop ing device
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							8.1.6. CLEANING
The toner attached to the surface of the OPC drum is transferred to the paper at the transcription stage, but a part of the toner
remains. The cleanin g is the stage that cleans the remain toner after the transcription stage. The remain toner on the drum and the
toner which was attached to the place where the laser beam didn´t scan are gathered to the develop ing roller to be used again.
W hen no paper is supplie d, the transcription roller is minus-charged to eliminate the minus-charged toner.
Cleaning Part
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							8.1.7. FIXING
On the process of the transcription, the transferred toner is weakly attached on the paper. Fixing means the process to fix the toner
on the paper permanently. The fixing part melts the toner at the high temperature using the halogen heater. The toner is fixed on
the paper by the heat and pressure through the fixing part with the image. The surface of the heat roller is rosined by Teflon and
lubricated to prevent from attaching the toners. The press roller is made of silicon, and its spring compresses the melted toner.
Fixing Part
The fixing part becomes high temperature, so the thermistor and the thermal fuse are provided.
 1. ThermistorThe thermistor touches the heat roller and check the temperature to feed back to the control circuit. The surface temperature
should be kept 178 °C while printing.
 2. The thermal fuse The thermal fuse plays the role to prevent the heat roller from rising to abnormal high temperature. The thermal fuse is located
near the heat roller and turns OFF the power when the temperature around the thermal fuse becomes over 121 °C. Once the
thermal fuse is turned OFF, it will not be turned ON again.
 3. Thermostat
The thermostat takes the same role with the thermal fuse. The thermostat is located near the heat roller, and it turns OFF the
power when the temperature around the thermostat becomes over 135 °C.
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