A Study on Torsional Stiffness of RV Reducer Considering Variable Loads and Tooth Modification

RV reducers have advantages of high torque ratio, and extremely reliable functioning in dynamical load conditions, etc., and they are extensively used in precision transmissions, such as industrial robots. The torsional stiffness of RV reducers is a main parameters affecting the meshing vibration and transmission performance. In addition, the variable loads and tooth modifications have significant influence on the torsional stiffness of RV reducers. In this paper, a new method of calculating torsional stiffness for RV reducers considering variable loads and tooth modifications is presented. The dynamic stress and deformation of meshing teeth are determined based on Hertz formulation, and the number of meshing teeth is analyzed through dynamic stress analysis. Then, the torsional stiffness of RV reducers is calculated. The influence of variable applied loads and different tooth modifications of cycloidal-pin gear transmission on torsional stiffness are also studied. The results show that variable applied loads and different tooth modifications influence the torsional stiffness of RV reducers by changing teeth deformation and clearance, respectively.