Modelling the Dynamic Interactions of Rolling Bearings

Roller bearings are wide spread machine elements. This work deals with the generation and propagation of structure-borne sound by the rolling movement in bearings. A physical model of the excitation mechanism in bearings in dependence of the condition of the surfaces and the dynamics of the rolling movement is presented. It allows the simulation of the time evolution of the excitation generated by the bearing that will propagate to the surrounding structure. Additionally, an experimental evaluation of the influence of the signal path between the point where the excitation is generated (in the bearing) to the point where it is usually measured (on the machine's housing) is also made using special self-made sensors and actuators. This alternative approach gives a deeper insight in the understanding of machine vibrations, describing the vibration source and the transfer path as part of a signal chain. This allows, among other things, the assessment of bearing conditions in operation and the optimization of the design of these elements.