TM 5-3805-263-14&P-3
AIR SYSTEM AND BRAKES
When the operator releases the foot brake pedal, the
pressure air in air compartment (9) is released through
If the operator pushes the foot brake pedal down
port (10) to an exhaust port. Spring (12) then pushes
completely, the control valve for the service brakes will
piston (11) back to the brake OFF position. Discs (8) are
send a large air signal to let the air pressure in the air
again free to turn between discs (7).
compartment (9) become higher. The friction between
discs will then-become great enough to stop discs (8),
CONTROL VALVE FOR PARKING BRAKE
hub (2) and wheel spindle 14
The location of the control valve for the parking brake is
under the console for the transmission shift lever. The
safety lever between slots for the transmission shift lever
operates the control valve.
CONTROL VALVE FOR PARKING BRAKE
1. Piston. 2. Stem. 3. Chamfer on stem. 4. Spring.
5. Supply port. 6. Exhaust port. 7. Delivery port.
1. Sprocket. 2. Hub. 3. Drive chain. 4. Shims. 5.
The flow of air is through a one-way check valve to
Wheel spindle. 6. Cover. 7. Discs (connected to
supply port (5). When the safety lever is pulled to the
spindle housing). 8. Discs (connected to hub). 9. Air
rear of its slot, piston (1) is moved into the control valve.
compartment. 10. Inlet port. 11. Piston. 12. Spring.
The piston pushes stem (2) down to open a passage
13. Wheel spindle housing. 14. Flange (part of wheel
from supply port (5) to delivery port (7). Chamfer (3)
spindle).
closes the opening from delivery port (7) to exhaust port
(6). Pressure air goes through the control valve through
the quick release valve to the rotochamber. Pressure air
in the rotochamber then releases the parking brake.
When the safety lever is pushed to the PARK
position, spring (4) moves stem (2) and piston (1) up to
stop the flow of air to delivery port (7). This opens the
passage from the delivery port to exhaust port (6). Air in
the line to the quick release valve is released through the
exhaust port. Pressure air in the rotochamber is then
released through the quick release valve. The spring in
the rotochamber can then engage the parking brake.
10. Inlet port. 13. Wheel spindle housing.
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