Have You Stressed Your Bell Curve Today?
Lee Guthrie, Pre-Stressed Products
A mechanical sine wave system is formed from a relatively thin sheet of spring material which is the ends to form a bell curve. The bell curve is positioned between two compressive members. A compressive force is then applied in a downward direction. The bell curve is compressed and shifts to form the relatively low frequency sine wave. As the force increases, the system shifts to a higher frequency wave with matching lower amplitude. For materials, this effect continues till the radius of the wave becomes prohibitively small, and the yield strength of the material is passed. If the force is removed prior to the material's yield point, the flexible material will return to its original shape. The force needed to shift the sine wave to the higher frequency increases at an exponential rate, as opposed to the linear rate as described by Hook's law (shown in graph). The threshold force needed to convert a low frequency wave to a higher frequency is much greater than the force required to maintain the new wave in its new stable state. This is the root of the energy absorbing/self dampening effect of the sine wave spring used in a mechanical system.