Theoretical And Experimental Research On Contact Performance And Mesh Stiffness Of Micro-segments Gear

Gear is one of the most widely used transmission parts, the core component for industrial production and equipment and where the key technology lies. Comprehensive research for Micro-segments gear — a non-involute gear, is not only the basis for its large-scale production and application, but also an important way to enhance the gear transmission performance.Currently, only a qualitative research based on FEA(finite element anal'ysis) is used for Micro-segments gear meshing stiffness in contrast with involute gear. Therefore, a comprehensive and in-depth study of the comprehensive Micro-segments gear mesh stiffness,particularly the contact stiffness,is of great significance.In this paper, the overall stiffness and the contact stiffness are two aspects considered for Micro-segments gear comprehensive meshing stiffness study, a theoretical model is established using fractal theory and potential energy method, based on the analysis and summary of domestic and foreign research methods for gear stiffness. And the model is verified by the FEA and experiment. The main work and achievements of this paper include:1) M-B(Majumdar-Bhushan) Fractal contact model is described and its principle of asperity contact deformation is discussed. For the research object, the cylinder contact factor and the friction factor are the introduced, the relationship between the contact area of the load is obtained with actual contact area and the critical contact area modified.2) Based on the revised cylinder fractal contact model, the influence of fractal parameters, such as fractal dimension, roughness amplitude, the material properties friction coefficient, on contact performance are obtained and the results of each are discussed and analyzed. A pair of Micro-segments gear is analyzed as numerical example.3) For the formula of the original fractal contact stiffness model and the fractal model are not fitted, a fractal contact stiffness model considering friction factors is obtained by revise, which can be used on Micro-segments gear. The resultes show the relationship between the coefficient of friction, the material properties, the contact form, size and the contact stiffness. And the coupling action of the fractal dimension and roughness magnitude is discussed.4) The potential energy method is applied to the Micro-segments gear stiffness calculation of the special advantages, as the principle of potential energy method and Micro-segments gear forming principle are discribed. A potential energy method for the Micro-segments gear stiffness solving model is established for the first time. Combined with Micro-segments gear fractal contact sitffness model, a new comprehensive meshing stiffness theoretical model for Micro-segments gear is obtained.5) Micro-segments gear tooth profile is obtained using Micro-segments gear accurate modeling program; rough contact surface profile and fractal parameters of tooth surface are measuring form the hobbing Micro-segments gear. A Micro-segments gear finite element model including the contact surface morphology is established for the first time.6) An optical measuring method is applied for Micro-segments gear meshing stiffness measurement after verifying its feasibility. The comparative analysis and discussion are made on the results of model and finite element method with the experimental results which verify the correctness and accuracy of the model results.