Vehicle Drive - FISCHER Profi Cartech Manual Del Usuario

The steering link connects the two steering knuckles to the steering knuckle
arm. This ingenious design of the link and arm is called a steering trape-
zoid. It ensures that the inner wheel inclines more in a curve than the outer
wheel. You can observe this in the fischertechnik model too. The steering
knuckles are turned to the left or the right using the steering rod.
Steering
Steering
rod
Steering
arm
Steering knuckle
Steering link
pin
Task:
Which advantages does steering with a steering knuckle have com-
pared to pivot-support steering?
Solution:
It requires less space, because the wheels rotate on a very short axle.
High degree of stability in curves, because the position of the wheels
hardly changes at all.
Less wear on the tires, because the wheels rotate precisely in the cor-
rect arc due to the different inclines of the outer and inner wheels.
Model: Vehicle with Four-Wheel Drive
(see the assembly instructions on page 28)
Fixed part
gear
of the front
axle
Steering
knuckle
Steering knuckle arm
Both the front and back axles have steering knuckles in four-wheel drive ve-
hicles. Both steering systems are connected and controlled using a steering
wheel.
Task:
What advantages does four-wheel drive have, and where is it used?
Solution:
Four-wheel drive steering makes it possible to turn within a small radius.
It is used when vehicles have to be especially maneuverable, e.g., in
cramped construction sites for earthmoving. In especially long vehicles
such as trailer trucks, the rear axle is also steered, because otherwise
there would be problems in normal curves.

5. Vehicle Drive

The engine is in the front in many vehicles, but it drives the rear wheels.
This section explains how the drive power from an engine is transmitted to
the wheels. This usually happens differently in reality from how it was done
in the Cartech models assembled until now.
Model: Vehicle with Drive Shaft and Bevel
Gear Drive
(see the assembly instructions on page 30)
This model contains a typical truck drive. The engine is in the front under
the driver's cab (not present) in our model. The power is transmitted via a
drive shaft to the rear wheel. We use a bevel gear to transmit the power at
a right angle. They are called this because their teeth are shaped like
cones..
Task:
In this model as in the previous ones with steering, only one rear
wheel is driven. Why?
Solution:
The rear wheels travel different distances in curves and rotate at dif-
ferent speeds. If both wheels were connected rigidly to each other and
driven, they would both rotate at the same speed and push the vehi-
cle straight forward. On the other hand, if only one wheel is driven,
the other wheel can run freely and rotate at any speed.
GB+USA
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