
SUSPENSION SYSTEMS 371
about its locating arms when the air lift bellows are
pressurized (Figure 22.33).
Coil spring actuated mechanical devices have also been
used to retract axles in earlier practice.
22.4 SHOCK DAMPERS
The need for shock dampers
Shock dampers play an important role in the motor
vehicle suspension system and work in conjunction with
the springs. The need for damping the action of the
springs can be readily visualized by considering the
gymnastics of a very simple vibratory system consisting
of a mass supported by a helical extension spring.
If a disturbing force momentarily displaces the mass
from its position of rest, the ...