Where are Springs Used? - Spring Manufacturers Institute

The many uses
of our products
By Konrad Dengler
Special contributor to Springs
Springs are necessary in many
technical constructions. The following
article gives an insight into
the wide variety of spring applications.
In addition, European
spring manufacturers describe
production examples and general
considerations for spring design.
A World of Springs
Objects of daily private or
business life wouldn’t work without
technical springs. In an article
published some weeks ago in the German
commercial newspaper Handelsblatt, Horst Dieter Dannert,
secretary of the German spring manufacturers association
VDFI, illustrated this fact well when he said, “Every light
switch, every valve, whether in a power station or in a
kitchen, needs a spring. Technical springs are everywhere,
where something is moving.”
The First Contact
Which was the fi rst spring you saw in your life? Maybe
it was a well-visible suspension spring of a baby carriage,
an automobile or a railroad car; maybe it was the torsion
spring of a clothespin; maybe it was when you took apart a
ballpoint pen. In this case, you noticed that objects contain
springs that are normally invisible, and, if the pen’s
small compression spring jumped out and disappeared, you
learned that springs have a clear technical function.
Springs are literally the basis of the physical world. The
author of this article remembers that, in one of his very fi rst
physics lessons, the teacher gave an introduction into the
matter of physical parameters and relations by means of the
“spring test.” The teacher fi xed a helical tension spring onto
a measuring scale and hung various weights on the lower
eye. The pupils observed a proportional relation between
load and spring length, and learned their fi rst physical formula,
which described “Hooke’s law.”
Everywhere!
Function Principle
Regardless of the particular function
of a spring, it can be said that all springs work
according to a principle: By changing their form, they store
energy or set it free. In this way, they enable the function of
technical systems, like a leaf spring in a door-handle; or they
act as cushions that bring harmful shock energy under control,
like disk springs in the buffer of an engine or a railroad
car. In every case, there is a play of forces and forms. As the
operating conditions can vary greatly, with many parameters
acting on the spring, there is a nearly endless number of
construction possibilities concerning the material, form and
structure of a spring.
Variety of Forms
Most springs show well-known forms. But there is no
form limitation. Springs can have a “typical” form like the
helical compression spring in a ballpoint pen, but a simple
blade or a clip can also be a spring, and there are even complex
forms that, at fi rst sight, seem to be works of modern
art. Some years ago, at the annual VDFI convention, Dr.
Thomas Blum from the managing board of the Wafi os engineering
works showed pictures of bizarre wire forms that
looked like abstract art but were technical springs. The curious
form was the result of a phenomenon that is well known
in the spring industry: The designer of a complex technical
system had forgotten to consider the spring in his construction.
Only at the end of the development process had he
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