Optimization Study On Machining Parameters Of Spiral Bevel Gears With Dual Duplex Spread Blade Method

In this dissertation,the spiral bevel gears with dual duplex spread blade method are taken as the research object,and the meshing performance of double flanks is predesigned.The completely conjugate tooth surface is used as the base tooth surface for the modification of the gear tooth surface.The deviation values of the tooth surface are determined by pre-determining the meshing performance of double flanks.Base on the Ease-off surface,the target tooth surface of gear is obtained by superimposing the deviation values of each point on the base tooth surface using.The mathematical correction model of tooth surface with machine-tool settings error is established.The sensitivity of tooth surface error to machining parameters is analyzed.The tooth surface errors can be eliminated by the selecting of machining parameters.Based on the proposed method,tooth contact analysis and finite element contact analysis are carried out.In the end,the feasibility of the presented method is verified by cutting and rolling inspection experiments.The main contents are as follows:1)The theory and method for double flanks machining of spiral bevel gears are studied.The geometric parameters and processing parameters of pinion are confirmed according to the basic geometric parameters of pinion.The position vector equation of the double tooth surfaces of pinion slots is determined based on the mathematical processing model of double flanks method.According to the meshing coordinate systems between the gear and pinion,the equations of the double tooth surfaces conjugated with pinion are obtained.The meshing performance of the tooth surface is controlled to determine the error values of ease-off surface.The Ease-off surface of the gear is established on the basis of the conjugate tooth surface.The tooth surfaces of both sides of the gear are modified to determine the target tooth surfaces of both sides of the gear which meet with the requirements of meshing performance.2)The tooth surface contact analysis of gear pair is carried out,and the relationship between transmission error curve and contact area shape,direction and machine-tool settings.According to the mathematical model of gear tooth surface and the machine tool processing parameters of gears,the optimization mathematical model including machine tool processing parameters is obtained the optimized gear tooth surface which is close to the target tooth surface.3)The rule of machine-tool settings on the geometrical shape of the tooth surface is determined by analyzing the sensitivity of tooth surface error to machining parameters.The sensitivity matrix of the tooth surface is established,and it is confirmed that the tooth surface error can be eliminated by the selected processing parameters.And the optimization mathematical model based on the sensitivity matrix is established.4)The tooth contact analysis is carried out based on the given pinion tooth surface and the optimized gear tooth surface to verify the consistency of the contact trace and the pre-seting contact trace on the gear tooth surface.Modeling and motion simulation are completed in 3D software UG.The finite element contact analysis is completed in finite element software.The gear cutting and rolling inspection are completed to verify the correction of the tooth surface modification design of gear based on dual duplex spread blade method.