General Method for Dynamic Analysis of Mechanisms Considering the Effect of Bearing Defects

Abstract

In order to effectively reveal the influence of bearing defects on dynamic response of high-speed mechanisms,a general method for dynamic analysis of mechanisms considering the effect of bearing defects is proposed in the framework of multi-body dynamics theory. In this method,the rolling element bearing joint in mechanism is constructed by using the force constraint. By analyzing the geometric contact relationship between rolling elements and defects on raceway surfaces,the contact load on each rolling element and the equivalent bearing constraint reaction force can be obtained. The influence of the bearing defect excitation on the performance of high-speed mechanism is explored. On this basis,a slider-crank mechanism containing a rolling element bearing with localized defects and distributed waviness defects on raceway surfaces is chosen as an example to demonstrate application of the methodologies. The results indicate that the defects can stimulate the sudden change of the dynamic load on each rolling element. After transmission,the vibration of the bearing load directly affects the state of motion of each component in mechanism and has a strong impact on motion stability of the high-speed mechanical systems. Furthermore,the theoretical method presented is general. Different bearing models with different geometrical defects can be embedded within this approach.