What is a torsion spring?

A torsion spring is a flexible elastic object that stores mechanical energy when it is twisted along its axis. When twisted, it exerts a proportional torque in the opposite direction. There are several varieties, including torsion bars, delicate torsion fibers, helical torsion springs, and spiral-wound clock springs.

What we know

• A torsion spring works by twisting its end along its axis to store mechanical energy. [2]
• When a torsion spring is twisted, it exerts a torque in the opposite direction proportional to the twist amount. [2]
• A torsion bar is a straight bar of metal or rubber subjected to twisting about its axis by torque applied at its ends, and a torsion spring is an instance of a spring. [1, 2]
• Torsion fibers are delicate forms made of silk, glass, or quartz under tension used in sensitive instruments. [2]

Where to go next

• how it workedHow do helical torsion springs work?
• a case in pointWhere are clock springs used?
• the bigger pictureWhat is a spring in physics?
• what caused itHow does shear stress affect torsion bars?
• how we knowWhat instruments use torsion fibers?
• an unexpected connectionHow do elastic springs relate to historical scientific instruments?Delicate torsion fibers made of glass or quartz are used in sensitive scientific instruments to measure tiny forces.

Sources

• [1]torsion spring (Wikidata Q27037480) · CC0 1.0
• [2]Torsion spring · CC BY-SA 4.0
• [3]Charles Bossut · CC BY-SA 4.0
• [4]Gilles de Rais · CC BY-SA 4.0
• [5]List of scientists whose names are used as units · CC BY-SA 4.0