Design and Optimization of Rocker in Pushrod Mechanism to Reduce Control Lag in Overhead Valve Engines

Abstract

This research focuses on the design and optimisation of the rocker in a pushrod mechanism as a novel way to alleviate control lag in Overhead Valve (OHV) engines. Off-road and high-performance vehicles require improved power efficiency and control qualities. Hence, OHV engines have gained popularity due to their longevity and low maintenance costs. However, its usefulness in high-speed applications is limited by control latency, which is mostly caused by the rocker and pushrod assembly. In the study, a novel rocker design with a 1:1.2 levering ratio is introduced and optimised for mass reduction through topology. The design's stress and deformation limitations are verified by finite element analysis, guaranteeing secure and effective functioning. The suggested design improves engine performance overall and minimises control delay by lowering the weight of the rocker by 19%. Lever ratio design, static analysis and topology optimisation are combined in this research to significantly reduce material consumption. The results of this study are not model-specific and provide generalizable insights that may be used to a wide variety of OHV engines in various car applications.