Kalmar ContChamp DRD S Series, Техническое руководство

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ContChamp DRD-S
Technical Handbook
Transmission
Description
3 S. Grupp 40
9407
04-10
The transmission consists of a torque converter integrated with
the gearbox, and a propeller shaft, driven axle with differential,
hub reductions and brakes.
The torque converter and gearbox run together, using a common
hydraulic system. The torque converter can be regarded as a hy-
draulic coupling and is located between the engine output shaft
and the gearbox input shaft.
Torque converter
The most important components of the torque converter are the
pump impeller, turbine wheel and stator. Engine power is trans-
mitted mechanically to the pump impeller. The impeller starts an
oil flow in the torque converter, and is comparable to a centrifugal
pump which draws oil into the centre and discharges it at the pe-
riphery.
The turbine wheel is located opposite the pump impeller and is
connected to the torque converter output shaft. The oil enters the
turbine wheel at the periphery and is discharged at the centre.
The stator is located between the pump impeller and the turbine
wheel, at their inside diameter. The function of the stator is to
guide the flow of oil from the inside diameter of the turbine wheel
back to the inside diameter of the pump impeller in the best pos-
sible way.
Torque conversion takes place in the oil circuit of the torque con-
verter. When the load on the truck increases, i.e. when the torque
required increases, the turbine wheel slows down in relation to
the pump impeller, and the oil flowing through the stator then in-
creases the torque.
The output torque gradually increases as the speed of the output
shaft decreases and is a maximum when the output shaft and
thus also the turbine wheel are stationary, i.e. are stalled, see
Technical data.
Gearbox
The gearbox is of constant-mesh type. Gear-changing is carried
out by clutch plates for the various gears being hydraulically ac-
tuated.
The valve body mounted on the side of the gearbox includes
spool valves which guide the oil flow to the various clutches. The
spools are activated in turn by solenoid valves. These are activat-
ed electrically by the gear selector in the cab. As an optional extra
an automatic gear changing system is available. See Group 20.
The gearbox has four ratios in each direction and is also provided
with disengagement, which is actuated by the brake pedal and
comes into operation at a certain brake pressure.
IMPORTANT!
The machine must not be run at stall
speed longer than 30 seconds at a time.
The torque converter will otherwise
overheat, causing damage to the seals
and thus necessitating expensive over-
haul.