The leaf spring saw two major advances over time. One
was the multiple leaf design. In a multi leaf spring,
several metal springs, of varying length and thickness are
bound together. This allows for a much stronger spring,
able to carry the weight of heavier cars and trucks. The
combination of spring sizes allows for greater tuning of
the spring characteristics. For example the spring can be
soft initially but then firmer the bigger the bump or the
rate spring, as it becomes increasingly stiffer the more its
compressed.
The second development was the movable shackle. A
shackle replaces one of the fixed mounting points of the
leaf spring with one that allows movement. As the leaf
spring is flattened under compression, its attachment point
moves further out. The shackle swings allowing the leaf
to stretch. This prevents binding of the spring, increases
the suspension travel and improves ride comfort sort-off.
What it really did was extend the useful life of the leaf
spring into the new millennium-mainly on low tech trucks.
was the multiple leaf design. In a multi leaf spring,
several metal springs, of varying length and thickness are
bound together. This allows for a much stronger spring,
able to carry the weight of heavier cars and trucks. The
combination of spring sizes allows for greater tuning of
the spring characteristics. For example the spring can be
soft initially but then firmer the bigger the bump or the
rate spring, as it becomes increasingly stiffer the more its
compressed.
The second development was the movable shackle. A
shackle replaces one of the fixed mounting points of the
leaf spring with one that allows movement. As the leaf
spring is flattened under compression, its attachment point
moves further out. The shackle swings allowing the leaf
to stretch. This prevents binding of the spring, increases
the suspension travel and improves ride comfort sort-off.
What it really did was extend the useful life of the leaf
spring into the new millennium-mainly on low tech trucks.
Leaf spring
Spring compression example
Suspension Designs
