Research On The Design And Motion Continuityof Recirculating Planetary Roller Screw

Planetary roller screw(PRS)has the advantages of high bearing capacity,high precision,and long service life,which has been applied to aerospace,medical devices,and precision machine tools.Among them,the advantages of the Recircular planetary roller(RPRS)are particularly prominent,but the related research results are less.In this paper,the working principle,kinematics,fatigue,and contact characteristics and dynamics of RPRS are studied.The main research work is as follows:(1)The working principle of RPRS is analyzed,and its structural parameters are derived.The virtual prototype with a nominal diameter of 25 mm,the pitch of 1 mm,and head number of 1 is designed,and the assembly and interference inspection are carried out.The material types and performance parameters of the main components were determined by the tensile test and hardness test.(2)Based on the constrained screw theory,the spatial degrees of freedom of RPRS is analyzed,and the relative motion of the mechanism is verified.Through the numerical analysis,the relative motion relationship between the components is deduced,the actual lead of RPRS is determined,and the influence of the relevant structural parameters on the actual lead is obtained.(3)The finite element model of RPRS is established.The vibration and fatigue characteristics of the mechanism under different support modes are analyzed in ANSYS Workbench and n Code Design Life software.The contact characteristics under different axial load and working temperature and the coupling of axial load and working temperature are studied.The contact stress and deformation laws of the mechanism under different working conditions are obtained.(4)The dynamic model of the RPRS was established,and the kinematics and dynamics simulation analysis of the mechanism was carried out in ADAMS software.The displacement and velocity curves of the lead screw,roller,and nut were obtained,which verified the rationality of the mechanism design;the collision force between the nut and roller and the actual lead curve of the nut output was obtained,and the axial load and the lead screw have studied The influence of helix angle on transmission efficiency verifies the condition of continuous motion of RPRS.