A parametric study on the free vibration of noncylindrical helical springs

In the work based on the stiffness method reported in this paper considering the rotary inertia, the axial and shear deformation terms, the natural frequencies of conical, barrel, and hyperboloidal-type helical springs fixed at both ends are calculated. The results are presented in dimensionless graphical forms for the six lowest natural frequencies of all types of noncylindrical helices for a wide range of vibrational parameters which influence the natural frequencies. A discussion about the effects of vibrational parameters on the natural frequencies is also presented.