Frustum helical springs are compact and stable. During operation, they withstand large loads, causing their stiffness to exhibit nonlinearity. Their load-deformation curve is divided into a linear region and a gradually increasing nonlinear region.
In the linear region, the stiffness coefficient is unaffected by the free height. Entering the nonlinear region, the mechanical characteristic curve of a frustum helical spring with a small free height is steeper, and the stiffness coefficient is negatively correlated with the number of effective coils. Compared to a cylindrical helical spring of the same external dimensions, a frustum helical spring can withstand larger loads and produce greater deformation, while having a smaller total compression height and superior lateral stability.
