Study On The Kinematics Of Cylindrical Roller In Double-side Processing And Mechanical System Improvement

Precision cylindrical roller is a key part of roller bearing,the precision and consistency of the cylindrical roller has a great influence on performance and working life of bearing.At present,outer circle centerless grinding is widely used for cylindrical rollers processing,but it is difficult to guarantee the precision and consistency.The method of double-sided lapping processing is adopted in this paper,ensure the lapping equiprobability of cylindrical surface by the principle of error averaging,and thus achieve the cylinder roller high precision and high consistency processing.In double-sided lapping,distribution of pressure,speed ratio among carrier and lapping plate,structure of carrier have a important effect on the precision and consistency in cylindrical roller processing.This paper combines kinematic analysis of workpiece and dynamics simulation analysis of loading system to guide the improvement design of original equipment,in order to develop a new ultra-precision double-side lapping machine for cylindrical roller processing.The main work and results are as follows:1.The angular velocity of cylindrical roller is one of major impact on material removal rate and workpiece forming.To analyze the movement relations between parts during processing,a kinematics model is built based on vector theory.More over,through experiment,the above mathematical model is been verified and the rotate speed combinations is optimized.The rotate speed of two lapping plates respectively relative to carrier revolution speed should be kept equal and the rotation speed of lower lapping plate and carrier shoule kept equal in order to make sure the uniform abrasion of lapping plate.2.The simulation analysis of dynamics characteristics of different loading system of double-side lapping machine are analyzed with ADAMS software.By studying contact force between cylindrical roller and upper plate to evaluate the characteristics of different loading system.It comes to the result that the tension-type with upper plate floating loading system is appropriate to the pressure loading in cylindrical roller processing.3.On the basis of previous study,the drive system,loading system and structure of carrier of original equipment are improved,achieving a uniform pressure loading,free to adjust the rotate speed ratio among carrier and lapping plate and carrier of eccentric movement.4.Lapping and polishing experiment of cylindrical rollers are carried out.In lapping experiment,semi-fixed abrasive plate is used,the effect of different carrier structure on the processing of cylindrical roller are studied.In polishing experiment,double-side lapping machine and flannelette pads are applied to polish the cylindrical surface of rollers,a smooth surface with low roughness are obtained.