Modeling Research Of Contact And Wear Prediction Of Joint With Clearance

In the mechanical system,the clearance of the kinematic pair is unavoidable,and the existence of the gap will affect the stability,reliability,motion precision and so on of the mechanical system.Therefore,in order to research and develop high precision machinery,it is of great theoretical and practical value to study the dynamic characteristics of the mechanical system with clearance hinges and the wear of hinges under the conditions of clearance.The contact wear of the hinge with clearance is studied in this paper.The details are as follows:A contact analysis method of the hinge with clearance is proposed.The method divides the geometric profile of the clearance hinge bushing into points,and determines the contact condition between the hinge elements and obtains the maximum contact depth by determining the distance between the discrete points and the geometric center of the hinge pin The normal contact force and the tangential friction force of the hinge are calculated based on the Lankarani-Nikravesh continuous contact force model and the Ambrósio friction model.Based on the Archard wear model,the dynamic modeling of the gap hinge wear is completed.The model can predict the wear of the joint and analyze the motion precision of the mechanism.The dynamic response of the mechanical system and the prediction of the wear of the bushing with the clearance hinge are analyzed by using the crank slider mechanism as an example.The test rig of slider-crank mechanism is carried out,and the vibration and wear experiment of the slider-crank mechanism is completed.The acceleration of the slider was measured by the acceleration sensor,and the obtained data were compared with the simulation results.The geometrical contours of the hinge bush after the experiment were measured by using the coordinate measuring instrument,and the results were compared and analyzed according to the calculated wear prediction.The results show that the theory and experiment are in good agreement,which verifies the rationality and accuracy of the modeling method.