Institutions Reliability Of A Number Of Thematic Studies

With the development of analysis method and design theory of reliability, the failure induced by structural destroy is more and more less, and the mechanism products are more developing toward high speed, heavy load, miniature and precise, the problem of moving mechanism failure is getting more and more important. So, on the basis of the available research, the kinematical accuracy reliability and wear reliability about mechanism are studied intensively in this thesis. The main innovative points are listed as follow:(1) The popular analysis methods of kinematical error about mechanism are studied, and a brief discuss is put on essential and applicability of Taylor series expansion method and transform mechanism method. From the view of mechanism kinematics, the three errors including dimension error, clearance of hinged joint, wear error induced by the moving disk-cam and roller are analyzed, and the corresponding calculation methods for position error on the follower of the disk-cam mechanism with swing roller are provided by using different analyzing methods. Taking various original errors mentioned above as random variables, the reliability analyzing model of kinematical accuracy about the position error of the follower is established on the basis of the theories of reliability and probability.(2) On the basis of available research about friction and wear, including wear style, wear principle and wear value calculation, the popular wear styles, such as adherence wear, abrasive wear and fatigue wear, are discussed, and the typical calculation models on wear value or wear rate are detailedly illuminated. A particular research is put on Archard model applied to calculate the wear value of adherence wear in this part. And then, the numerical calculating method of wear body imposed periodic load is provided under the use time is given, and the corresponding reliability analyzing method and calculating model are established.(3) The wear reliability on extending-retracting mechanism of nose landing gear of a military aircraft is analysesed and calculated. First, the question of linkage wear isresearched, and the corresponding reliability analyzing method and calculating model are established. And then, on the basis of the analysis of extending-retracting mechanism, including geometry relation ^ kinematical relation and load relation, the wear failure probability of extending-retracting mechanism is calculated and argued under given design extending-retracting number.