Panasonic KX-MB2230RU / KX-MB2270RU / KX-MB2510RU / KX-MB2540RU Service Manual ▷ View online
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KX-MB2230RU/ KX-MB2270RU/ KX-MB2510RU/ KX-MB2540RU
6.8.6.
2W1-2 phase excitation
1. Timing chart
2. Wave form
CLKCD
(Pin46_IC502)
COUT1
(Pin52_IC502)
ADF Motor
current*
Fig. 6
5V/Div
10V/Div
0.5A/Div
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KX-MB2230RU/ KX-MB2270RU/ KX-MB2510RU/ KX-MB2540RU
6.9.
FAN Motor Section
6.9.1.
General
This unit is equipped with two FAN motors to prevent the developing devices, Low Voltage Power Supply board (SMPS Board) and
other devices from overheating during printing.
The FAN rotates at high speed (Approx. 3000rpm) while printing.
After printing is finished, FAN rotates at low speed (Approx.2200rpm) while predetermined period.
other devices from overheating during printing.
The FAN rotates at high speed (Approx. 3000rpm) while printing.
After printing is finished, FAN rotates at low speed (Approx.2200rpm) while predetermined period.
6.9.2.
Circuit Diagram of FAN
Two FAN motors are controlled by following one circuit.
Depending on a model, the number of fans is one.
So the operation of two FAN motors (Full speed rotation/Half speed rotation/Stop) are controlled simultaneously.
Depending on a model, the number of fans is one.
So the operation of two FAN motors (Full speed rotation/Half speed rotation/Stop) are controlled simultaneously.
6.9.3.
Fan Control
For the control of FAN speed, comparator IC (IC504) is used.
This IC compares (+) side input level and (-) side input level.
If (+) side input level is bigger than (-) side input level, output of this IC is "OPEN".
If (+) side input level is less than (-) side input level, it outputs "L" level.
This IC compares (+) side input level and (-) side input level.
If (+) side input level is bigger than (-) side input level, output of this IC is "OPEN".
If (+) side input level is less than (-) side input level, it outputs "L" level.
6.9.3.1.
Half Speed Mode
In half speed mode, IC300_pin K25 outputs pulse (frequency is about 30KHz, duty is about 37.5%).
This pulse is integrated by R644 and C618 then Pin2_IC504 becomes approx. DC1.24V. Input level of IC504_pin2 is determined by
the voltage of between R624.
If voltage between R624 is less than 1.24V, output of pin1_IC504 becomes "H".
Then both Q606, Q607 and Q603 are turned on. So voltage between R624 (=the voltage of pin2_IC504) rises gradually.
When the voltage between R624 exceeds 1.24V, output of pin1_IC504 becomes "L".
Then both Q606, Q607 and Q603 are turned off. So voltage between R624 falls gradually.
By repeating these sequences, voltage between R624 is controlled approx. 1.24V.
On the other hand, if FAN voltage is represented Vo and voltage between R624 is represented VL, VL is determined as below for-
This pulse is integrated by R644 and C618 then Pin2_IC504 becomes approx. DC1.24V. Input level of IC504_pin2 is determined by
the voltage of between R624.
If voltage between R624 is less than 1.24V, output of pin1_IC504 becomes "H".
Then both Q606, Q607 and Q603 are turned on. So voltage between R624 (=the voltage of pin2_IC504) rises gradually.
When the voltage between R624 exceeds 1.24V, output of pin1_IC504 becomes "L".
Then both Q606, Q607 and Q603 are turned off. So voltage between R624 falls gradually.
By repeating these sequences, voltage between R624 is controlled approx. 1.24V.
On the other hand, if FAN voltage is represented Vo and voltage between R624 is represented VL, VL is determined as below for-
mula.
VL=Vo*R624/(R623+R624)
→ Vo=VL*(R623+R624)/R624
Since each value is as follows, Vo is determined approx. 9.7(V).
VL=1.24(V), R623=150(Kohm), R624=22(Kohm)
Vo=1.24*(150K+22K)/22K=9.7(V)
Vo=1.24*(150K+22K)/22K=9.7(V)
Therefore by reducing the voltage of FAN power supply, FAN rotates with half speed.
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KX-MB2230RU/ KX-MB2270RU/ KX-MB2510RU/ KX-MB2540RU
6.9.3.2.
Full Speed Mode
In full speed mode, IC300_pinK25 outputs constant 3.3V.
When Q606, Q607 and Q603 are turned on, Vo becomes approx 20V (approx.4V drops between R616, R617).
So the voltage between R425 is determined as follows
When Q606, Q607 and Q603 are turned on, Vo becomes approx 20V (approx.4V drops between R616, R617).
So the voltage between R425 is determined as follows
VL=Vo*R624/(R623+R624)=20*22K/(150K+22K)=2.5(V)
Since IC504_pinA3 is 3.3V and IC504_pinA2 is 2.5V, pin1_IC504 is always "H".
Consequently all Q606, Q607 and Q603 are always turned on, and then approx 20V is supplied to FAN motors.
Therefore FAN rotates with full speed.
Consequently all Q606, Q607 and Q603 are always turned on, and then approx 20V is supplied to FAN motors.
Therefore FAN rotates with full speed.
6.9.3.3.
FAN stop
When IC300_pinK25 is "L", both Q606, Q607 and Q603 are turned off, then both FAN stop rotation.
6.9.3.4.
Rotation detect signal
During the FAN rotation, the pulse signal is output from pin 2 of FAN motors as the rotation detects signals.
If the period of the pulse is wider than predetermined value, it is judged that FAN error occurred.
Then display shows "Call Service 4".
If the period of the pulse is wider than predetermined value, it is judged that FAN error occurred.
Then display shows "Call Service 4".
6.9.4.
Control table
FANON1H
(IC300_pin
K25
)
FAN1and FAN2 mode
H
Full speed
Pulse
Half speed
L
Stop
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KX-MB2230RU/ KX-MB2270RU/ KX-MB2510RU/ KX-MB2540RU
6.9.5.
Waveform
6.9.6.
Abnormal Detect and Lock Protect Block
This block detects the FAN abnormal condition such as FAN motor lock or Extra low current caused by insufficient connector inser-
tion of FAN.
When FAN motor abnormal condition occurs, it may cause damage to FAN itself and machine by the overheat.
So at the abnormal condition, FAN motor current must be stopped automatically and machine operation must be stopped.
tion of FAN.
When FAN motor abnormal condition occurs, it may cause damage to FAN itself and machine by the overheat.
So at the abnormal condition, FAN motor current must be stopped automatically and machine operation must be stopped.
When error condition is detected, display shows "Call Service 4"
3.3V
3.3V
3.1V
0.6V
0.6V
24V
20V
30KHz
3.3V
1.2V
1.2V
0.6V
0.6V
12V
9.8V
(1)Full speed (H:20usec/Div)
Point D(1V/Div)
Point C(2V/Div)
Point B(2V/Div)
Point A(2V/Div)
Point F(5V/Div)
Point E(10V/Div)
Point D(1V/Div)
(2)Half speed (H:20usec/Div)
Point D(1V/Div)
Point C(2V/Div)
Point B(2V/Div)
Point A(2V/Div)
Point F(5V/Div)
Point E(10V/Div)
Point D(1V/Div)
Ground level
Ground level
Peak Level
Peak Level
Ground level
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