A I R S Y S T E M A N D B R A K E S
A I R C I R C U I T F O R T H E E M E R G E N CY
A N D P A R K I N G B R A K E
TM 5-3805-258-24-1
S Y S T E M S
O P E R A T I O N
WARNING
L O C A T I O N O F T H E C O N T R O L K N OB
2. Knob.
If the knob moves back out immediately after it
is pushed in, the pressure in the air system is
not enough to release the parking brake. Do not
move the machine until the air pressure is at
the correct pressure for operation. Operation
of the machine with the parking brake engaged
will destroy the brake and cause a fire.
Air from the reservoir goes through orifice (8) and
outlet port (7) to the parking brake. The pressure in
port (7) will hold valve (9) against cover (10) which
closes exhaust port (11). The parking brake is now
released.
When the brake air pressure indicator goes off and
the fault alarm stops (operating pressure is reached),
When knob (2) is pulled out again, the pressure in
the operator must push in and hold knob (2) (move
outlet port (7) will release through exhaust port (11).
knob to OFF position) to release the parking brake.
The parking brake is again activated.
The control valve for the emergency and parking
brake will activate automatically when the pressure
of the air system goes below approximately 280 kPa
(40 psi). At this pressure, spring (5) moves valve (9)
in an up position against valve body (4) and the
parking brake is activated. When the control knob is
moved to the ON position, the transmission is auto-
matically disengaged.
AIR PRESSURE SWITCH FOR EMERGENCY
AND PARKING BRAKE
L O C A T I O N O F T H E A I R P R E S S U R E S W I T CH
1. Switch.
Air pressure switch (1) is activated when the air
pressure to the parking brake gets below approxi-
mately 450 kPa (65 psi). The switch causes the
parking brake indicator in the dash to come ON.
C O M P O N E N T S O F T H E C O N T R O L V A L V E
3. Plunger. 4. Valve body. 5. Spring. 6. Inlet port from air
Switch (1) is fastened to the quick release valve
r e s e r v o i r . 7 . O u t l e t p o r t t o e m e r g e n c y a n d p a r k i n g
of the brake chamber for the emergency and park-
brake. 8. Orifice. 9. Valve. 10. Cover. 11. Exhaust port to
ing brake.
open air.
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