Research On Positioning Accuracy And Transmission Efficiency Of Hybrid Ceramic Planetary Roller Screw Pair

As a precision transmission component,the transmission characteristics of the planetary roller screw pair will directly affect the performance of the CNC equipment.In order to adapt to the development of numerical control equipment to heavy load,high speed and high precision,higher requirements are put forward for the planetary roller screw pair.In order to inherit the advantages and make up for the shortcomings of the planetary roller screw pair,this paper proposes to replace the metal roller with ceramic roller to improve the accuracy of the displacement of the working nut and expand the use range of the planetary roller screw pair.In this paper,by matching analysis and comparison of the material,the silicon nitride ceramic was selected as the material of the roller.According to the movement relationship of the planetary roller screw pair,the structural size of the screw,the roller and the nut and the number of rollers are determined.Based on the Hertz contact theory,this paper analyzes the contact characteristics between the roller and the thread raceway,and compares it with theoretical calculation and finite element simulation.It analyzes the influence of the contact deformation of the roller and the raceway on the contact accuracy.This paper analyzes the influence of the introduction of the silicon nitride ceramic roller on the axial deformation,and summarizes the factors affecting the displacement of the working nut of the planetary roller screw pair.It considers the contact deformation between the roller and the raceway contact surface,and derives the formula of axial deformation and stiffness according to the deformation coordination relationship between the components.It analyzes the factors affecting the displacement error of the working nut and proposes measures to improve the positioning accuracy.This paper analyzes the contact state of the planetary roller screw pair,analyzes the friction characteristics of the silicon nitride ceramic roller and the thread raceway and the frictional force.This paper analyzes the influence of structural parameters on friction torque and proposes measures to reduce friction and wear.On this basis,the establishment of a planetary roller screw pair drive efficiency calculation model to explore the factors that affect the transmission efficiency.