Evaluation of the Influence of the Mass and Stiffness in the Vibration of the Command of Valves System in Internal Combustion Engines

The objective of this work is to do an experimental analysis of mass and stiffness (rigidity) parameters alteration and its influence in the valve train behavior. The valve train vibration contributes considerably to noise level and is related to acoustic comfort, performance and durability of the cylinder head. Three valve train configurations were used to a comparative analysis. The first configuration was the reference (base line). In the second configuration the mass of the group was increased. In the third configuration a different valve spring was used to alter the rigidity of the group. Acceleration sensors were installed in strategic positions (inside and outside) of the cylinder head to measure vibration levels in vertical and horizontal plans that permitted a comparison between the configurations results. Vibration levels in the vertical plan do not show significant variations to the three configurations, whilst in the horizontal plan the rigidity the configuration rigidity showed lower intensity in the vibration level in relation to the reference configurations and mass which performed alike.