Parametric Design And Dynamic Analysis Of Thin Wall Four-Point Contact Ball Bearing

As an important part of wrist joint,thin-walled four-point contact ball bearing plays an important role in the dynamic performance of industrial robot equipment.This article comes from the National Natural Science Foundation project "High Performance Rolling Bearing-Spiral Bevel Gear System Flexible Multi-Body Contact Dynamics Study"(1146 2008).In order to complete the digital design method of the thin-walled four-touch ball bearing structure and meet the needs of the special supporting bearings for industrial robots,it is necessary to study the theoretical methods,dynamic characteristics and fatigue life of the thin-walled four-touch ball bearing design for industrial robots.And obtained The influence laws,analysis methods and optimization results of key main parameters.At the same time,obtained the thin-walled four-point contact ball bearing with optimized performance.Taking the thin-walled four-point contact ball bearings for industrial robots as the research object,the main research contents of this paper are as follows:(1)According to the structural characteristics of thin-walled four-point contact ball bearings,analyzing the main parameters of the bearing structure and the standard sub-parameters of the industry,and establishing the digital full-parameter geometric structure model of thin-walled bearings.Taking the mechanical properties of the bearing as the objective function and the main parameters of the structure as the design variable,the structure parameters of the bearing are optimized.Based on the parametric multi-body dynamics model of the bearing,the effects of the main parameters on it’s mechanical properties are studied.Because of the curvature of the channel and the clearance have a certain relationship,this key structural parameter needs to be carried out.The curvature of the outer channel,the curvature of the inner channel,and the key parameters of the radial clearance are the design variables,and different mechanical properties are the target functions.The optimal combination analysis of design variables was carried out to obtain the geometrical parameter modelof the thin-walled four-point contact ball bearing with optimized mechanical properties.(2)In order to solve the problem of excess and interface contact of the bearing,the finite element analysis model and flexible multi-body contact dynamics analysis model of the bearing,hollow shaft and base of the wrist of the industrial robot are established by using the finite element method and multi-body dynamics method.The dynamic properties of the wrist joint with a thin-walled four-point contact ball bearing-outer hole base-hollow shaft flexible multi-body and multi-interface contact of the industrial robot are studied.(3)Taking conventional deep groove ball bearing as an example,the fatigue life acceleration test is carried out to obtain the influence of the fatigue life of the bearing.Compared and analyzed basic rated life,modified rated life and fatigue life,obtained the factors affecting of bearing life.Based on the load distribution law of the bearing-hollow axle-base,the nominal and fatigue life of the thin-walled four-point contact ball bearing is calculated and analyzed by simulation,and the service life of the bearing is predicted.