The shock resistance of incandescent lamps

Abstract

A theory for the deflection of a coiled filament under a transverse mechanical load has been developed. For small values of the load the coil can be considered as a beam and for large values as a chain. In the first case the elongation stiffness can be neglected and in the latter the flexural rigidity. For these limiting cases the internal stresses in the wire can be calculated. It is shown that under shock conditions there is good correlation between the amount of plastic deformation of the coil and the internal stresses in the wire of the coil.