Researchof Thermal And Particle Generation Characteristicsfor Planetary Roller Screw

Planetary roller screw(referred to as PRS) with high speed, high precision and over loading characteristics has been more and more widely used. However, there is a lack of research on the affects of factors such as friction, lubrication on PRS, and currently we lack appropriate testing methods and equipments.This paper focuses on thermal and particle generation characteristicsfor planetary roller screw, which is related to friction performance,designing and manufacturing test stand for amount of particle generation, layinga strong foundation for following studies such as friction, lubrication, particle generation characteristicsand so on.This paper contains following parts:Firstly the factors causing frictional moments are analyzed, and then the frictional moment that is principally generated by spinning sliding of roller is calculated based on the Hertzian contact theory. Meanwhile lubricants and their characteristics related to particle generation are introduced.Secondly basic theory of thermal analysis is introduced, and based on symmetric model in cylindrical coordinates system, thermal conduction differential equation is built, both steady-state heat conduction and transient heat conduction finite element equationsare established. Through the reasonable simplification of PRS, the finite element modelis obtained.With a certain type of PRS, heat sourcesare analyzed, the boundary conditionsare determined, then thermal characteristics and thermal deformation are analyzed under different conditions, finally the thermal deformation suppression methods are discussed.Thirdly the characteristics of particle generation of mechanical products were studied. We have analyzed resources and the factors affecting the amount of particle generation,meanwhile the general particle generation characteristics are obtained. Particle generation life is introduced, and its estimation formula is given, considering the factors of material, environment, lubricants and load.Fourthly the testing principle of the amount of particle generation for mechanical system including PRS is analyzed, the functional requirements and technical specifications of the test stand are studied, and the test stand is designed and manufactured.The testing conditions are given.Through the test results, the factors affecting particle generation characteristics are analyzed.This paper,providesreferences for thermal deformation suppression ofmechanicalsystem including planetary roller screw, the test stand,which has goodpracticability and expansibility, can be effectively applied to particle generation test for a variety of othermechanical systems,...