Study On Wear Of Revolute Joint GAP And Its Application In Mechanism

Mechanical equipment in the joint clearance wear is inevitable.Turning the vice gap and its wear and tear caused by the accuracy of degradation,vibration,noise and other issues,a direct impact on the stability of mechanical equipment and service life.Especially after long-term work,the joint clearance becomes larger and larger as the degree of wear being deepened,and these problems become more prominent.The existing multi-body dynamics model of sub-gap wear is not perfect for describing the wear process of the mechanism.In particular,the study of the interaction between force flow transmission-mechanism movement and joint sub-gap wear is not yet very significant thorough.It is difficult for designers to analyze the reliability and life expectancy of mechanical equipment,also the designers can not predict the equipment life accurately and monitor the movement status of the mechanism.In this paper,aiming at the problem,based on the theory of multi-body dynamics system and gap collision theory,the wear of the joints clearance and its influence on the mechanism performance are studied.The specific works are as follows:1)An efficient method for predicting the wear of the joint secondary clearance is proposed.The model can include the intrinsic and external factors of the mechanism,such as friction coefficient,mechanism load,moving speed and performance of parts materials.At the same time,the test system of joint secondary gap wear was established and the test method was established.The method of predicting the wear of secondary clearance was verified.The test mechanism has the advantages of high flexibility,adjustable parameters,simple operation and high repeatability of experiments,abling to carry out a variety of simple wear test mechanisms.The accuracy of the model was verified by this test mechanism and good results were obtained.2)Aiming at the analysis of the wear of different materials in the joints,based on the consideration of the life of the revolute joints,the preferred method of revolute auxiliary materials was proposed.The method uses the maximum depth of wear in the revolute joints as the life evaluation index.When the maximum depth of wear reaches a certain level,it can be considered that the movement of the revolute joints does not meet the requirements.With the advantages of high efficiency,simple judgment,small amount of calculation,this method provides a good reference for selecting the turning joints in the actual project.3)The method to analyze the influence of the wear between the joints clearance of the low speed mechanism on the accuracy of the mechanism was proposed.Then we got the different results how the wear of the revolute joints clearance at different positions was affected by the accuracy and performance of the mechanism.Finally,the wear of the revolute joints clearance which had a great influence on the mechanism performance was considered to be the key weakness.