Axial Vibration of Metal Flexible Couplings

Abstract

Metal flexible couplings are widely used in connecting shafts of rotating machines, since they have a simple structure, need no lublication, accommodate large misalignments of shafting and so on. However this coupling inclines to generate an axial vibration because of low axial stiffnesses of metal flexible plates. In this paper an experimental apparatus composed of a driving motor, a metal flexible coupling and a driven shaft, is constructed in order to investigate characteristics of axial vibration of the coupling under various conditions. The thickness and the number of flexible metal plates are varied in four and three levels respectively and the three different misalignment (axial, parallel, angular) conditions are considered. Further a formula for evaluating the axial stiffness of the flexible plate is theoretically derived, and the natural frequency calculated from this formula is in good agreement with the experimental one.