Terex TS14G, Руководство по обслуживанию

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4
Section 250-0000
Braking System - Air Braking System Schematic
SM 1784 Rev 2 04-04
c. Park/emergency brake circuit air pressure falls
below 5.5 bar (80 lbf/in
2 ).
If light illuminates while operating, stop the machine,
apply the parking brake and do not operate until the
fault has been corrected.
OPERATION
Numbers in parentheses refer to Fig. 1.
Air from the engine driven air compressor (1) travels
through air drier kit (2) via pressure protection valve
(6) and into all four air tanks (3, 4, 17 & 18).
Air flows to the front primary tank (3) and service
brakes via port '21' of the pressure protection valve
(6). Air is supplied to the rear primary tank (16) and
service brakes via port '22' of the pressure protection
valve (6). Air is supplied to the front and rear
secondary tanks (5 & 18) and park/emergency brake
valve (8) via port '23' of the pressure protection valve
(6). Air is supplied to the auxiliary components via port
'24' of the pressure protection valve (6).
Air compression is controlled by unloader valve on air
drier (2) stopping and starting delivery of air from air
compressor (1) when maximum 8.4 bar (122 lbf/in²)
and minimum 6.5 bar (95 lbf/in
2 ) pressures are
reached.
The pressure in the system should not exceed
8.4 bar (122 lbf/in²) if the system is operating normally.
However, if unloader valve malfunctions and the
pressure continues to rise, safety valve on air drier (2)
will open to protect the air system by relieving the
pressure at 13 bar (190 lbf/in²).
Service Brake
Depressing treadle valve (9) allows air to flow directly
to the service ports of the front brake chambers (10)
via the front primary tank (3). Air is also directed to the
rear brake chambers (21) via relay valve (19) to apply
the service brakes.
The amount of air that flows to brake chambers
(10 & 21) depends on how far treadle valve (9) pedal is
depressed. The farther the pedal is depressed the
greater the air pressure in the brake chambers
(10 & 21) and the greater the braking force.
The brakes are released when the treadle pedal is
released. Air pressure is exhausted through treadle
valve (9) exhaust port.
Park/Emergency Control Valve (8) -
Controls air
pressure delivery to the relay emergency valve for
actuation of brake chambers to apply the brakes. In
the 'PARK' position it exhausts the air from the spring
applied brake chambers, to apply the parking brake.
Refer to Section 250-0190, PARK/EMERGENCY
CONTROL VALVE, for detailed operating and
servicing procedures.
Treadle Valve (9) -
Directs and controls air to the front
and rear relay emergency valves which control air
delivery to the brake chambers. Refer to
Section 250-0070, TREADLE VALVE, for detailed
operating and servicing procedures.
Brake Chambers (10 & 21) -
Actuate slack adjusters
to apply front and rear brakes during service brake
system operation: or automatically in case of an
extreme loss of air pressure or for emergency
applications. Also mechanically locks brakes on in
parking mode. Refer to Section 250-0260, BRAKE
CHAMBERS, for detailed operating and servicing
procedures.
Quick Release Valves (11 & 22) -
Installed adjacent to
brake chambers to hasten the exhaust of air from the
brake chambers when the applied air pressure is
released. Refer to Section 250-0180, QUICK
RELEASE VALVE, for detailed operating and servicing
procedures.
Relay Valve (19) -
Speeds the application and release
of air pressure to and from tractor and scraper brake
chambers. Refer to Section 250-0280, RELAY VALVE,
for detailed operating and servicing procedures.
Brake Light Switch -
Turns on the brake lights when
the brakes are applied.
Warning Light (Air System)
The following warning light is controlled by pressure
switches and is located on the right hand warning light
panel in the operators compartment:
Note: Refer to operators handbook for location and
identification of warning light.
Low Air Pressure (Red) - Illuminates when there is a
loss of air pressure in the following circuits:
a. Front service circuit air pressure falls below 4.1 bar
(60 lbf/in
2 ).
b. Rear service circuit air pressure falls below 4.1 bar
(60 lbf/in
2 ).
Courtesy of Machine.Market