Research On Contact Parameters Of Planetary Roller Screws And Analysis Of Contact Conditions

Planetary roller screw pair has been widely used in related fields due to its many advantages.However,the performance of planetary roller screw pairs produced in China is still insufficient,which limits the development of planetary roller screw pairs in China.Therefore,in order to improve the design and manufacturing level of planetary roller screw pairs in China,this paper takes the structural parameters of standard planetary roller screw threaded teeth as the research object,and carries out theoretical analysis from meshing characteristics,load distribution,transmission efficiency.Firstly,in order to obtain the corresponding relationship between the structural parameters of the threaded teeth and the contact parameters of it,the meshing contact equation was established according to the meshing principle and the knowledge of coordinate transformation.The corresponding contact parameters were solved by the improved Gauss Newton iteration method,and the calculation formula of the axial clearance was derived.On this basis,the axial clearance of planetary roller screw pairs are calculated from the three aspects of thread tooth structure parameter error,roller position error and attitude error.According to Hertz contact theory and stiffness theory,the load distribution equation of each thread of planetary roller screw pair is established,and the influence law of thread structure parameters on load distribution is analyzed.The correctness of the equation is verified by finite element analysis.Finally,in order to get the relationship between the structural parameters of threaded teeth and transmission efficiency,according to the motion characteristics of planetary roller screw pair,the mechanism of friction formation of planetary roller screw pair is analyzed,and the mathematical model of transmission efficiency of planetary roller screw pair is established,and the rationality of the mathematical model is verified by experiments.The contents and results of this paper can provide a theoretical basis for the design of planetary roller screw pairs with high load-carrying capacity and long service life.