Coil spring

This article does not cite any references or sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (December 2007)

A compression coil spring A tension coil spring A selection of conical coil springs Oxy-cut spring showing deformation due to loss of tempering in adjacent turn

A Coil spring, also known as a helical spring, is a mechanical device, which is typically used to store energy and subsequently release it, to absorb shock, or to maintain a force between contacting surfaces. They are made of an elastic material formed into the shape of a helix which returns to its natural length when unloaded.

Coil springs are a special type of torsion spring: the material of the spring acts in torsion when the spring is compressed or extended.

Metal coil springs are made by winding a wire around a shaped former - a cylinder is used to form cylindrical coil springs.

Variants

The two usual types of coil spring are:

• Tension coil springs, designed to resist stretching. They usually have a hook or eye form at each end for attachment.
• Compression coil springs, designed to resist being compressed. A typical use for compression coil springs is in car suspension systems.

Degradation

Many types of coil spring are wound in an annealed (soft) condition and then tempered to achieve their strength as a spring. Over time, this tempering can be lost^{[citation needed]} and the spring will sag because it can no longer withstand the loads applied. Such springs can be re-set by annealing, returning to their original length (or deliberately setting them to a different length) and then re-tempering. Damage to springs, such as using oxy-acetylene to cut the end off a car suspension spring to lower a vehicle's ride height, can destroy the tempering in localised areas of the spring.

External links

• Helical Spring by Sándor Kabai, The Wolfram Demonstrations Project.
• Chamberlain Spring (basic equations and glossary)
• Institute of Spring Technology
• Spring Manufacturers Institute

This design-related article is a stub. You can help Wikipedia by expanding it. v • d • e