Design and Development of Experimental setup for Direct Acting Overhead Camshaft (DOHC) Valve System

Abstract

The reduction in the frictional losses in the valve system has been the focus of many studies in the past. The complexity of the interaction between the various tribological interfaces of the valve system requires its accurate evaluation. Since the interacting cam and follower tribo pair passes through boundary, mixed and elastohydrodynamic lubrication regimes in a single cycle, therefore analytical estimation of its performance, measured in terms of the frictional torque, is complex. Therefore the performance evaluation of the cam and follower mechanism is generally carried out experimentally. This paper presents the design and development of an experimental test setup for Direct Acting Overhead Camshaft (DOHC) valve system for the study of effect of spring stiffness, preload and cam operating speed on friction between the cam and follower. The experiments were performed using radial offset cam and roller follower and the results are reported.