STRESS ANALYSIS OF A CYLINDRICAL COIL SPRING OF ARBITRARY CROSS SECTION. (1ST REPORT, SOLUTION BY FOURIER EXPANSION COLLECTION METHOD).

This paper presents a theoretical analysis for obtaining stresses of a spring of arbitrary cross section. In the analysis the stresses of a straight rod subjected to torsion, shear and bending are derived based on the two-dimensional theory of elasticity by means of the Fourier expansion collocation method which has been reported by the author. The results for a coil spring are derived by including the curved rod theory in the expressions for a straight rod. The present result is applicable to the problem of coil springs by merely including the geometrical data on the spring, whatever the shape. The numerical results obtained by this analysis are in very good agreement with the previously published ones for some typical cases.