Study On Modal Analysis Structure Optimization Method Of Gearbox

As an essential link and transmission power in the transmission system, the Gear Box is a common component of mechanical equipment, its design standards and manufacturing technology to some extent is a reflection of the country's comprehensive national strength and the market competitiveness, and as the rapid development of science and technology, and people put forward a higher demand at transmission power of big, small size, light weight, little vibration, low noise. Due to the poor working conditions, the gear box will vibrate arising from the incentives outside; gear will have an impact in the meshing process, the shock pass through the shaft and bearing to the gear box, which cause the vibration. The vibration of Gear box can easily lead to wrong and the fatigue damage, reducing the life of gearbox. To carry out the study of the dynamic characteristics about gear box has become essential.At present, the use of modal analysis techniques to estimate the dynamic characteristics of mechanical structures has become an effective way, to combine the finite element modal analysis and experimental modal analysis, with experimental modal analysis to testify and correct the finite element model has become a trend, while the use of modern optimization techniques in the weight, deformation, stress, etc is increasingly common.The topic focuses mainly on the modal analysis of the gearbox, and predicts the dynamic characteristics of gear box, then do the optimization analysis on a proper finite element model of gear box. This paper describes the structure of modal analysis and structural optimization study of the status quo at home and abroad, and the finite element analysis of theoretical and experimental modal analysis theory, so as a variety of experimental modal parameter identification method, based on the finite element model of gear box, do the finite element modal analysis, by analyzing the impact of the finite element modal shape, adjust the cabinet to reduce the local stiffness of box deformation. Making use of single point of encouraging and multi-response experimental modal analysis to do experimental modal analysis of gearbox, Use the PolyMAX to identify the modal parameters. Based on the experimental modal analysis, compare the modal parameters to verify the validity of finite element model. Finally aimed at the deformation of the gearbox, do the structure optimization analysis. The maximal effect force of statics analysis is bound variables, to minimize deformation of gear box as the optimization objective, reasonably optimize the structure. Optimization results show that the optimized box reduces the amount of maximum deformation of 15%, the maximal effect force is reduced by 22.5%, to improve the overall performance box. Optimized gearbox mode natural frequency to avoid the meshing frequency and its octave, and will not occur the resonance dued to structural changes.