Spring Shackles

2.5.5. Spring Shackles

Fig: Spring Shackle

A shackle is an integral component of the suspension system that attaches between the leaf spring and the vehicle frame. It allows for the leaf spring to work through length changes during suspension articulation.

The leaf packs, or leaf springs, position and center the axle under the vehicle. They also support the vehicle's weight, since these are a primary component of the suspension system.

As a leaf spring flexes up or down, its length from main eye to shackle eye changes. Since one end is mounted solidly (the main eye), and cannot move, the length changes happen at the shackle end of the leaf pack.

A spring shackles can be used for leaf spring fitment; leaf spring can either be attached directly to the frame at both ends or attached directly at one end, usually the front, with the other end attached through a shackle, a short swinging arm.

The shackle takes up the tendency of the leaf spring to elongate when compressed and thus makes for softer springiness. Some springs terminated in a concave end, called a spoon end (seldom used now), to carry a swiveling member.

Fig: Shackle