Modeling and validation of dynamic performances of timing belt driving systems

A modeling method for a generic layout of timing belt driving system (TBDS) is presented, and the formulas for modeling a meshed teeth belt, an automatic tensioner, and rotational pulleys are established. A numerical method consisting of an iterative algorithm for calculating the dynamic responses of system is proposed. One engine TBDS with a crankshaft, a camshaft and a tensioner is taken as a studying example. The method and the procedure for obtaining the dynamic responses are described and studied. The dynamic performance of the TBDS, such as oscillation angles of pulleys and tensioner arm, and the transmission error between pulleys, are calculated and compared with the measurement, which validates the presented method. The influence of tensioner performance (stiffness and damping), meshed teeth model and different belt pre-tensions on the dynamic responses of a TBDS system are investigated. The tensioner behavior and belt tension are also analyzed based on the calculated dynamic responses. The developed method presented in this paper can be used for predicting the dynamic responses, optimizing the parameters of an engine TBDS, and reducing the design period and the cost for prototype validation.