On the Periodic Response of Cam Mechanism With Flexible Follower and Camshaft

Abstract

Researchers in recent years have shown a great deal of interest in the study of the dynamic response of cam-follower systems, with one or more of its components treated as being elastic. Within the assumption of a lineaar analysis, and limited to stable regions, a single degree-of-freedom linear second order differential equation of motion is developed for a cam mechanism consisting of elastic follower and camshaft. This development is consistent, as are some simplifying assumptions, with the works of current authors. The governing equation is shown to possess time-dependent periodic coefficients, for a constant imput angular velocity. Conventionally, the rise portion of the cam motion cycle has been treated as the source of excitation, and the transient follower-motion computed during the excitation (rise) as well as the subsequent dwell periods. The one basic assumption in these works, however, has been that the residual vibration is damped out during the dwell period and does not carry over to the next motion cycle. In this paper, the authors forego this assumption and present a method for not only incorporating the excitation effects due to the return stroke, but also for obtaining the steady-state response of the follower. Some illustrative examples are presented, and even though no comprehensive set of cam-profile types are examined, some basic conclusions are reached using a representative cycloidal cam profile.