The Development Of Wear Tester And The Wear Analysis Of Mechanism With Clearance

With the development of modern technology and mechanical engineering,the higher performance of mechanical equipment,such as accuracy、reliability are demanded.However,the existence of clearance in joints has a larger impact on mechanical performance.In addition,the wear of joint can also cause the performance decrease of the mechanical equipment after long time running.In this paper the pin-bushing tribological tester is developed and the wear test of joint is researched,futhermore,the dynamic and wear characteristics of mechanism with clearance are analyzed.To simulate the wear condition of joint in mechanism system and consider the effect of atmosphere,a pin-bushing tribological tester is self-developed for the research,it can test the properties of materials in vacuum or special atmosphere.The development of tester is mainly divided into three parts,that is the mechanical structure system、the gas and sealing system、the data collection and control system.Considering the structure of tester and working conditions,the influencing factors of wear test are determined.The orthogonal test method is employed through the comparative analysis of different test method,and the tribological properties of 45 steel-HT250 gray iron couples are investigated under dry condition both in air and nitrogen atmosphere.Considering the complexity and time variability of wear process,the wear prediction model is established based on the neural network by using the experimental data,and the test results indicate that the prediction model has a higher fit and prediction performance and it can reflect the wear laws that underlying experimental data.Considering the clearance in mechanism joints and based on the non-linear elastic-damping model,the dynamic model of slider-crank mechanism is established and the kinematic parameters are got through numerical simulation;at the same time,the dynamic model of circuit breaker mechanism is established as an instance by using ADAMS software,and the kinematic parameters are got through ADAMS simulation.Then the parameters are employed respectively as the input of the trained prediction model to predict the wear of dangerous joint through repeated iteration.It can be seen from analysis that wear occurs seriously in some special areas on bushing surface,and more seriously in the test atmosphere than air.The research provides the theoretical basis for the development of wear tester and the optimization and fault diagnosis of the circuit breaker mechanism,and also offer a method to analyze the phenomena that couple various kinematic parameters and joint wear.