A torsion spring is a device used to give support and cushion movement in several types of components. There are two distinct types of torsion spring. The first is not a spring at all, however, it has torsional or spring-like properties and is called a torsion bar. The second one is actually a helical-wound spring, such as the type of spring used in a common mouse trap. The torsion bar is commonly used in automobile chassis, as well as trailer suspensions. Typical applications for torsion springs include: Computer Camera Door Machine Electric appliance Furniture