Kinetic Parameter Identification Of Bearing Joint And Research Of Dynamic Property Of Gearbox

Abstract:Gear transmission system is widely used in all kinds of transmission forms in mechanical equipment. The vibration of the gear box has a comprehensive effect by shaft, gears, bearings, housing and so on. There is a widespread problem to simulate the joint accurately in building the dynamics analysis model of multiple parts system. The stiffness of bearing between shaft and gear box have a great influence on dynamic characteristic of the gear box system. In order to build the finite element model of the structure accurately, we should take to understand the features of joints.A single stage gearbox is taken as the research object in the paper, and a method to identify the equivalent stiffness of bearing accurately is put forward, based on the vibration theory, finite element modal analysis, modal test and parameter optimization method. The identified parameter is applied to the finite element analysis, where the results of inherent characteristics and dynamic response are got exactly. The full text of the research contents and results are as follows:1. The finite element analysis model of gear box is built based on Abaqus, and the equivalent stiffness of bearing is simulated by spring unit of three directions. The inherent characteristics of gearbox components and system are calculated by finite element modal analysis.2. The natural frequencies and vibration modes of the gearbox contains bearing information are acquired by modal test with the testing system and test plan.3. The stiffness of bearing is obtained by parameter optimization based on finite element modal analysis and modal test results, while the damping of bearing is inferred by the relationship between the physical parameters and the modal parameters.4. The bearing dynamic reaction force in gear meshing process is simulated by the gear torsional vibration multi-body model and transient modal dynamics method is applied to calculate the the dynamic response of the gear box conclude gear, drive shaft, bearing and box.5. The gear box test rig is built to test the vibration of the gear box under normal working state, and the test results are compared with the simulation results.The research results show that the proposed parameter identification method of bearing joint and the finite element analysis method has good simulation precision. The established finite element analysis model and test model is good consistency in the dynamic performance, and the method can be applied to the analysis of practical engineering problems.