Research On Bearing Cylindrical Roller Size Sorting System And Contact Dynamics Of Measuring Process

Cylindrical rollers are the main parts of bearings.Excessive size differences will affect the accuracy,operation performance and service life of bearings to varying degrees.Therefore,it is particularly important to reduce the size difference of bearing rollers.At present,in the domestic bearing industry,the manual measurement method is mainly used to measure the roller size,which has the characteristics of poor roller sorting accuracy,large error and low efficiency.It is difficult to meet the requirements of modern bearing accuracy.The bearing cylindrical roller size sorting system designed by our research group can avoid the shortcomings of manual detection.In order to ensure the measurement accuracy of the sorting system to meet the design requirements,this paper focuses on the research of the measurement system of the bearing cylindrical roller size sorting system.Under the working conditions,the dynamic measurement generated when the roller contacts with the sensor contacts in the measurement process is analyzed.The main factors causing errors are found out,and the error compensation of dynamic measurement results is realized based on BP neural network model.First,the working principle of the measurement system is explained,and the mathematical model of the contact between the cylindrical roller and the sensor is established.The influence of the speed of the cylindrical roller on the collection of the diameter sensor is analyzed,which leads to the error of the measurement size.Considering that the feeding device uses electromagnetic vibration hopper to work,the excessive vibration frequency will cause the instability of the whole machine,and the measurement accuracy of the measurement system will be deviated.Through theoretical analysis of the electromagnetic vibration hopper,the vibration frequency under its working conditions is compared with the natural frequency of the measurement system.When the two resonances occur,the measurement errors produced by the measurement system are analyzed,which provides a theoretical basis for subsequent simulation analysis.Second,in order to more accurately analyze the main factors causing errors in the whole dynamic measurement process,different cylindrical roller velocities and vibration frequencies are set as the influencing factors,orthogonal experiments are designed,and dynamic simulation of contact collision between roller and sensor is carried out by using Adams dynamic software.The maximum values of contact force in the y-axis direction and expansion of sensor contacts are taken as reference.The main factors affecting the accuracy of the measurement system are obtained by combining range analysis and variance analysis.Final,the simulation results are used to design the experiment,collect the experimental data of cylindrical roller diameter,establish the BP neural network model,and program with Matlab.The experimental data are trained to get the prediction data and the reference size data.The error rule under the dynamic measurement is found out and the dynamic measurement error compensation is realized.In this paper,the dynamic measurement error analysis of the bearing cylindrical roller size sorting system and the error compensation based on BP neural network model are carried out to make the whole machine meet the measurement accuracy requirements.The research on the bearing size sorting system has important theoretical significance and practical value.