A GLOBAL–LOCAL INTEGRATED STUDY OF ROLLER CHAIN MESHING DYNAMICS

It has been recognized that one of the most significant noise sources in roller chain drives is from impacts between the chain and the sprocket during their meshing process. In this paper an analysis is presented which integrates the local meshing phenomena with the global chain/sprocket system dynamic behaviour. A coupled chain/sprocket system interacting with local impacts is modelled and the impulse function is derived. A study is carried out to quantify the intensity of subsequent impacts. It is found that the coupling effects between the sprockets, the chain spans, and the chain/sprocket meshing impulses increase with decreasing sprocket inertia and chain longitudinal stiffness. Experimental studies are also carried out to evaluate the meshing noise. It is found experimentally that the meshing sound pressure level is closely related to the chain speed and its vibrational characteristics, as predicted in the analytical study.