Kalmar ContChamp DRD S Series, Техническое руководство

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ContChamp DRD-S
Technical Handbook
Brake system
Description
23 S. Grupp 70
9407
04-10
Cooling circuit
When the accumulators are charged, oil is fed to the cooling oil
cavities in the drive axle. A by-pass valve between the supply and
return lines ensures that the cooling oil pressure will not exceed
1,5 bar, in order to protect the drive axle.
The feed is carefully cleaned through filters. The hydraulic fluid is
cooled by means of a fluid cooler. Machines with a separate tank
for the brake system have one hydraulic fluid cooler for the wor-
king hydraulics and one for the brake system.
Main components of the brake system
Numbering refers to system illustrations and hydraulic
diagram (H).
5. Hydraulic pump, which generates the brake pressure and is
driven by a power take-off on the variable pump.
21. Accumulator charging valve, serving as a priority valve which
gives first priority to the brake system. The remaining flow is
delivered to the cooling circuit.
22. Accumulators which are charged by the accumulator charg-
ing valve, are pre-charged with nitrogen and ensure that pres-
sure will be available in the brake circuit even if the engine
should temporarily stop.
23. Accumulator evacuation valve, opened for emptying of accu-
mulator to the tank before any work is carried out on the hy-
draulic system. Valve 25 must be opened when draining the
system.
24. Safety valve 210 bar
25. Valve for reserve servo pressure. Used in emergency situa-
tions if the engine does not run and servo pressure is needed
for the working hydraulics. When draining the system, both
this valve and the accumulator evacuation valve (23) should
be opened.
29. Brake pedal. Supplies oil at a reduced pressure from the ac-
cumulator to the drive axle disc brake assembly.
30. Disc assemblies in the wheel hubs.
31. Release clutch switch, disengages the transmission at a giv-
en brake pressure.
32. Sensor, brake lights
33. Sensor, low brake pressure (accumulator pressure), acti-
vates lamp 45 on the instrument panel
34. Parking brake valve which supplies fluid at a reduced pres-
sure from the accumulator to the parking brake cylinder when
the parking brake is released. Sensor 31 switches on the
parking brake warning lamp when the parking brake is ap-
plied, and also initiates a signal to a buzzer in the cab to indi-
cate that the operator has left the seat without applying the
parking brake.
36. Parking brake cylinder. Actuated by a heavy spring when the
brake is applied, i.e. when the oil has been discharged
through the parking brake valve. The brake is released by hy-
draulic oil from the parking brake valve.
41. Hydraulic oil cooler with electrically powered fan
43. Separate tank for the brake system