A coil 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.
source/image: Hydraulic Press Channel
The torsion bar is a length of spring steel with splined or square ends. One splined end is fixed to a lever arm that forms part of the suspension. The bar rotates as the lever arm moves up and down. Watch the video from Hydraulic Press Channel
How strong/stiff are car springs? We test car spring, van spring, downhill mountain bike spring and some home made metal springs that are made from copper, aluminum and silver.
We use our 40 ton Hydraulic press and 150 ton and 5 ton force sensors.Even after the press compacts the spring down into a flat ring and pushes so hard that sparks fly and the place stinks of burnt rubber, the spring still hops back up once the pressure is off and tries to assume its former shape.