Research On Thermal Deformation Of The Holes On The Gear Box Of Automobile

With the improvement of mechanical precision and measurement accuracy, the error caused by thermal deformation in proportion to mechanical precision continues to increase. More and more domestic and foreign scientists research to the basic theory and the practical application of engineering of mechanical thermal deformation. However, the research of the non-similarity thermal deformation of complex physical structure is rarely. with the support of National Natural Science Foundation "Mechanical complex physical thermal robustness basic research" (project number:51175142) and the National Natural Science Foundation of major projects "coupled modeling and functional mechanism of influence shaped surface structure and properties" (Project No: 51490660/51490661),with the support of common models automotive transmission provided by the company as the research object, Systematically explore the non-similarity thermal deformation and the simulation of the box bearing bore.The main work is completed as follows:Systematically introduces the status quo of mechanical thermal deformation at home and abroad, indicating the significance of mechanical thermal deformation; the history, current situation and problems of the automobile transmission thermal deformation at home and abroad are summarized.Based on the basic theory of mechanical thermal deformation, proposed thermal conversion theory, the complex body was subjected to thermal distortion simulation analysis comprehensive taking about finite element method, and through the experiments and simulations analysis of common geometric body to verify the feasibility of the theory and simulation methods.Using self-developed small Abbe Error CMM systems to measure the thermal deformation of the bearing bore on the automobile transmission case. Relevance double coordinate function mapping method proposed for experimental data analysis, study in-depth of the thermal deformation of the bearing bore and each bearing bore center space trajectory deviation, calculating the relative spatial positions after both ends of the gear shaft bearing hole thermal deformation.In the thermal deformation analysis of the transmission case bearing holes to study the effects of the transmission gear performance. Calculated the gear shaft corresponding mounting holes center distance error and eccentricity errors caused by thermal deformation and analyzed the variation of the degree of overlap and instantaneous transmission ratio.Finally, simulation analysis the thermal deformation of the transmission case bearing bore, structural mechanics simulation model by heat converted simplify the mechanical structure surrounding the bearing hole form factor to apply to participate in the form of surface force load modeling. Compare the simulation results to the experimental data to verify the simulation results.