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3. Auto Sweep Motor Circuit
●
Fig. 4-1 shows the Auto sweep motor drive circuit; the signals shown in Fig.4-2 are output from pins
15
–
22
of microcomputer.
●
As the microcomputer’s outputs change as shown in Fig.4-2, the core of the auto sweep motor is excited
to turn the rotor. Table 4-1 shows the rotation angle of horizontal air deflectors.
Table 4-1 Auto sweep Motor Rotation
Rotation angle per step (˚ )
Time per step (ms.)
0.0882
10
Horizontal air deflectors
Microcomputer pins
Step width
Horizontal air
deflectors: 10ms.
Horizontal air deflectors
15
16
17
18
1
2
3
4
5
6
7
8
19
20
21
22
Fig.4-2 Microcomputer Output Signals
Fig.4-1
Microcomputer
22
21
20
19
18
17
16
15
R711
R712
C712
0V
Q712
Q711
IC711
C71
1
9
7
10
11
12
13
15
16
P.W.B. MAIN
14
6
5
4
3
2
1
8
0V
CN8
M
M
M
12V
D712
CN7
Rotor
Auto sweep motor for
horizontal air deflector
1
2
3
4
5
6
7
8
9
10
1
2
3
4
5
6
7
8
9
10
11
AUTO SWEEP
MOTOR
AUTO SWEEP
MOTOR
AUTO SWEEP
MOTOR
●
The air deflectors are driven by the stepping motors, which are instructed by the microcomputer.
●
The air deflectors on the left and right are each driven by two stepping motors.
●
The stepping motors and main unit are connected via relay connectors. The air deflectors will not operate
unless the relay connectors are connected: Securely connect the relay connectors identified by colors
when attaching the panel.
●
Before removing the panel for servicing, be sure to disconnect the relay connector to protect the lead
wires.