Torsion springs are helical springs that exert a torque or rotary force. The ends of torsion springs are attached to other components, and when those components rotate around the center of the spring, the spring tries to push them back to their original position.
Torsion springs are usually used over a supporting rod or arbor for most effective operation, they can be produced with either left-hand or right-hand coil direction. Spring ends are available in several standard forms, including short hook, hinge, straight offset, straight torsion, and double torsion. Hook and special ends are designed and manufactured especially to meet your requirements.