Research On The Performance Optimization Of RV Reducer Crankshaft Bearing With Full Cylindrical Roller

RV reducer with the advantages of high transmission accuracy,compact structure and strong carrying capacity,has been widely used in industrial robots,aerospace,national defense science and industry and other fields.A large number of applications show that crankshaft bearing is the weak link in RV reducer,and its life determines the life of RV reducer.Therefore,it is of great significance to carry out research on structural innovation and performance optimization of RV reducer crankshaft bearing to improve the performance of RV reducer.In view of the deficiency of the existing RV reducer crankshaft bearing structure,this paper proposes an integrated design with crankshaft and cycloid gear,which is full of cylindrical roller bearing structure.The main work of this paper includes:(1)Put forward an integrated design of crankshaft and cycloid gear with full cylindrical roller bearing structure,carried out motion analysis and force analysis on it,deduced the fatigue life formula of the crankshaft bearing,and studied the influence rule of each parameter inside the reducer on the life of the crankshaft bearing.(2)It is set the basic dynamic load rating for single objective optimization function.Design variables include four geometrical parameters: the bearing pitch diameter,the diameter of the roller,the effective length of the roller,and the number of rollers.And the constraints are given on geometry,strength,lubrication and friction.And the sensitivity of optimization results is analyzed.Optimization results show that the fatigue life of RV reducer can be improved by optimizing design method.(3)On the basis of the single objective optimization,multi-objective optimization is carried out for RV reducer crankshaft bearing.Taking the basic rated dynamic load and the stiffness of rotary bearing as the objective function,the multi-objective genetic algorithm(NSGA-II)was used to optimize the optimal solution set,and the optimal design was selected from the solution set.(4)According to the optimization results,the sample reducer was trial-produced,and performance indexes such as transmission efficiency,transmission precision and torsion stiffness of the reducer before and after the optimization were compared,so as to simulate the actual working conditions of the reducer and build an accelerated fatigue test bench for the accelerated fatigue life test.