Surface Quality Of Precision Ball Screw Pair Raceway Grinding Process And Its Experimental Research

As an important transmission part of modern mechanical structure,ball screw pair has been widely used in precision machine tools,automation transmission,aerospace and other fields.There is currently a large gap between the performance of the ball screw pair in foreign country and the performance of the ball screw pair in China.The preliminary investigation shows that the surface quality of the raceway is one of the main factors that affect the performance of the ball screw pair.In order to improve the surface quality of the ball screw pair and improve the performance of the product,The following aspects of the surface quality of ball screw pair raceway are studied in this paper by combining theoretical analysis and experimental research.Firstly,the technological factors affecting the surface quality of the screw and nut raceway are summarized,and the theoretical analysis is made from the grinding parameters,the characteristics of the grinding wheel,the grinding wheel dressing,the vibration of grinding,the cooling mode and the raw material on the surface quality of the screw and the nut raceway,which provides the theoretical guidance for the grinding test.Secondly,experimental research is carried out from two aspects: optimization of grinding process parameters and grinding of screw raceway.The grinding tests of ball screw and ball nut are carried out by two methods of orthogonal test design and single factor analysis.Through the analysis of the test results,the main and secondary order of the influence of grinding wheel grain size,wheel speed,workpiece speed and grinding depth on raceway surface roughness is defined.The optimum combination of various parameters in grinding process is clarified and the influence of the parameters on the roughness of the raceway surface is given,which provides guidance for the selection of the parameters of the grinding and machining of the screw and nut in the future.Using grinding technology to improve the surface quality of ball screw raceway,three raceway grinding schemes were proposed and the effectiveness of grinding to improve the surface quality of the raceway was verified by experiments.Then,the influence of raceway surface quality on the friction torque of ball screw pair is studied.The structure design of the friction torque test-bed is completed.The composition of the data acquisition system and the selection of the sensor and acquisition card are given and the corresponding measurement software is developed with LABVIEW.On this basis,The influence of different surface roughness on friction torque of KD4016 end ball screw pair is compared and the relationship between the roughness of the raceway surface and the friction moment is clarified.Finally,from the two aspects of raceway surface roughness and surface waviness,the influence of raceway surface quality on the noise performance of ball screw pair is studied.The composition and function of the comprehensive performance test bench for the ball screw are introduced and the design of the noise measurement and analysis system is completed.On this basis,the effects of the surface roughness and ripple of the KD4032 end plug ball screw pair on the noise performance are measured.The test results show that the forced vibration caused by the surface ripple of the raceway is the most important factor to cause noise.Therefore,the improvement of the surface processing quality can significantly reduce the noise and is the main measure to improve the high speed performance of the ball screw pair.