Hino 600, Workshop Manual, Page: 413 / 451

ABS (ABS : FULL AIR) BR03–10
b. PRESSURE REDUCTION MODE
•
When solenoid coil (1) is energized, solenoid valve (3) opens and air
also flows into pilot chamber (14). It pushes down on diaphragm (5),
shutting off chambers (7) and (8). At the same time, solenoid coil (2)
is also energized. This causes solenoid valve (4) to open and the
operating air from pilot chamber (12) passes through exhaust port
(15) and is released into the atmosphere. Consequently, the air from
the outlet port (9) side (brake chamber) pushes down on diaphragm
(11) and air is released into the atmosphere. This causes the air pres-
sure of the brake chamber to decrease.
c. PRESSURE MAINTENANCE MODE
•
When solenoid coil (1) is energized, solenoid valve (3) opens and air
flows through chamber (7) and acts on pilot chamber (14). On the
other hand, since solenoid coil (2) is not energized, solenoid valve (4)
is closed and air flows through pilot hole (10) and acts on pilot cham-
ber (12). This causes diaphragms (5) and (11) to shut off their air pas-
sages, and the chamber (8) pressure, that is to say the air acting on
the brake chamber, is maintained at the pressure that was current
when the switch from the pressure reduction mode to the pressure
maintenance mode took place.
Pressure reduction
Solenoid valve for driving inlet
valve 3
Solenoid valve for driving
exhaust valve 4
Time 0
V
alv
e oper
ating status
Status
Pressure
ON
ON
Br
ak
e chamber
pressure
14
5
3
7
1
2
4
15
11
12
8
9
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Pressure maintenance
Solenoid valve for driving inlet
valve 3
Solenoid valve for driving
exhaust valve 4
Time 0
V
alv
e oper
ating status
Status
Pressure
ON
OFF
Br
ak
e chamber
pressure
14
5
3
10
8
1
2
4
12
11
SHTS068020300013