Collision Dynamics And Reliability Design Of Linear Rolling Guide

With the development of numerical control equipment towards high speed,the performance requirements of linear rolling guide are becoming more and more important which is an important part of numerical control machine tool.Because its working performance plays a decisive role in the quality of products produced,the research on reducing the vibration and noise of rolling linear guides has attracted wide attention.It is necessary to carry out research on the collision characteristics of rolling linear guides,the establishment and analysis of collision dynamics models and reliability analysis.The main research contents of this thesis include:(1)Based on the knowledge of elastic mechanics and kinematics,the collision characteristics of rolling linear guide system are studied.According to the motion characteristics of ball and carriage in linear rolling guide system,the initial velocity of ball colliding with carriage and the period of ball colliding with carriage are calculated.Then the impact force of the ball on the carriage has been studied,and the relationship between the maximum deformation of the ball and the initial velocity of the collision has been analyzed.The relationship between the maximum impact force of the ball on the carriage and the initial velocity of the collision,the radius of the ball and the mass of the ball has been also analyzed.Finally,the contact time between the carriage and the ball is studied,and the relationship between the contact time and the initial velocity is analyzed.(2)Based on the force analysis of the linear rolling guide system,considering the effect of ball on carriage,and combining the impulse theorem,the single-degree-of-freedom collision dynamics model of the linear rolling guide system was established.Then the collision model of first order vibration differential equation with integral is solved by runge-kutta method and the dynamic analysis is completed.The influence of different impact impulse on the vibration characteristics of the collision system is studied.The influence of different excitation frequency,different initial contact angle,different preload,different transition zone length and different slider length on the dynamic performance of the collision system is studied.Finally,the influence of the basic parameters of the system on the contact stiffness and frequency response of the carriage-guide collision system is studied.(3)The reliability analysis of the linear rolling guide collision system is carried out by the fourth-order moment method and Edgeworth series method,and the reliability of the collision system is obtained.Then the sensitivity analysis of the rolling linear guide collision system is carried out,and the influence of the four basic parameters of the slider groove radius,the guide rail groove radius,the ball diameter and the initial contact angle on the reliability of the system is analyzed.Finally,the Monte Carlo method is used to verify the correctness and effectiveness of the fourth-order moment method for the reliability of the collision system.(4)Through the research of this paper,the collision dynamics model of the rolling linear guide system is established.Essentially,the influence of the impact impulse of the ball on the vibration characteristics of the linear rolling guide system is analyzed.The influence of preload,initial contact angle and excitation frequency on the dynamic performance of the collision system is also analyzed.It has great significance to reduce the vibration and noise of the rolling linear guide rail system and to improve the dynamic performance of the system.