In the present work a new method for the modeling of timing chain drives is presented. This method allows to consider the dynamic behaviour of three-dimensional structures, for example chain guides and surrounding structures, in the dynamic simulation of chain drive systems. The model is validated on a two-sprocket drive with measurement results from a chain drive test rig (measurements carried out by IWIS Motorsysteme GmbH & Co. KG). The occurring rotational irregularities at the driven sprocket, the bearing forces and the oil pressure in the chain tensioner are used for the validation. The simulation results show a good correlation with the measurement in the rotational irregularities of the driven gear (amplitudes in the resonance points deviate by ~ 20-25% from the measurement). Also, the bearing forces at the driven gear can be well predicted concerning the amplitudes and frequencies (deviation of resonance frequency <10 \%). A second focus of this work is the physically correct modelling of hydraulic chain tensioners based on known boundary conditions such as geometry, oil data and operating condition. Depending on the tensioner type, different components are essential for proper modelling. Especially at tensioners with high working oil pressures the leakage gap geometry and the position of the plunger in the housing are influencing the dynamic behaviour. It can be shown that the consideration of all relevant physical effects in combination with an assumed eccentricity of the plunger leads to a good match of the simulated dynamic behavior (range up to 200 Hz) with the measurement without "tuning” the model. The maximum occurring tensioner forces at a given sinusoidal path excitation and frequencies of 25 to 200 Hz found in the simulation differ by a maximum of 20 % from measured ones. This allows the modelling of chain tensioners for chain-drive dynamics simulation without relying on tensioner hysteresis data from measurements.
|Translated title of the contribution||Simulation of the dynamic/acoustic behaviour of timing chain drives|
|Publication status||Published - 2019|
Bibliographical noteembargoed until 18-01-2024
- dynamic simulation
- chain drive dynamics
- hydraulic chain tensioner
- tensioner hysteresis