Design Analysis of a Snap-Action Mechanism

Abstract

A simple analytical approach is used to describe the nonlinear behavior of an initially curved, transversely loaded beam with fixed ends; the end supports are assumed to be rigid (constrained against displacement along the beam axis). It is shown that, for the proper choice of initial shape, the beam duplicates Belleville spring behavior while having the added advantage of no support point friction. The negative rate necessary for snap-action can be readily determined from curves or calculations. Equations are presented in forms which are convenient for use by the designer.