Research On Automatic Vibration Detection Technology For The Second Generation Hub Bearing Unit

The hub bearing unit is an important part of the Automotive Transmission System. The second-generation and the third-generation hub bearing units are widely used in automotive industry currently. Bearing vibration is an important index, which directly reflects whether the quality of bearing is up to standard. In this thesis, the bearing vibration measurement was studied and the vibration detection system of the second generation hub bearing unit was developed for a project, relating technologies at home and abroad.The primary works in this thesis are presented as follows:The national detecting standard for the general rolling bearing was introduced and the detection system project of the second generation hub bearing unit was designed according to the standard and relevant technologies.The physical construction of the vibration detection system was designed, which was realized base on pneumatics. The test scheme was designed as separation stations in this thesis and the different mechanisms were used for the different stations to match the special appearance of the second generation hub bearing unit.The monitoring system for the vibration testing system was designed. The selection of hardware parts and the designing of the measuring soft were also finished in this thesis. The monitoring system worked based on the virtual instruments which gathered signals, processed data and displayed human machine interface through IPC and controlled the process of mechanical movement by PLC.The accuracy of the detection system was verified by experiment. Both the signals collected at the scene and the processing results were analyzed to check the accuracy of the system.The experimental result verified that the accuracy of this system reached the design requirement, but there is still room for improvement. Such as adding more features of vibration signal analysis, enabling the system to get more information from the bearings of vibration signals; improving the mechanical structure to make the work piece drive smoother and the loading accurate of wheel bearings higher and so on. These can be used as more in-depth research topics.