1. Clips

For some of these springs, known as clips, elasticity is only useful when they are inserted into a housing. Once in the housing, the clip relaxes and can only be released by re-tensioning it with special tools. Rings (figure 1 a ), circlips (figure 1 b ) [43] , segments (figure 1 c ), snap fasteners and many other clips fall into this category.

Other springs apply a constant force to the component they are holding in place, the value of which corresponds to the deflection given to the spring. This is often a leaf, helical or conical spring inserted after...