Non-linear Dynamic Model and Its Solution for a High Speed Cam Mechanism with Coulomb Friction

Abstract

The dynamic behavior of overhead cam mechanisms, commonly used in automotive applications, is strongly influenced by the Coulomb friction at the rocker arm pivot. In this study, a non-linear one-degree-of-freedom model of such a mechanism including Coulomb friction has been developed. An exact quasi-linear solution to the equations representing the non-linear behavior has been obtained. The effects of Coulomb friction at different cam speeds are investigated using typical parameter values. A critical examination of the simulation of the dynamic behavior of the cam mechanism by using an equivalent viscous damper to replace the Coulomb friction is made.