Finite Element Analysis Of Spiral Bevel Gear Based On Precise Tooth Surface Model

Because of its large load capacity, high coincidence degree, transferring load smoothly, reducing noise and vibration in the high-speed transmission, large transmission ratio, not sensitive to the installation error, the spiral bevel gears are widely utilized. In this paper, spiral bevel gear in the final transmission system of a launcher for the object, some contact problems are studied, with MATLAB, VB, SolidWorks, ANSYS, and so on. The main contents are as follows:1.Based on gear meshing theory and principles of local conjugate, in accordance with the principles of flat-top generating gear and relative position in processing, establish a tool coordinate system, a machine coordinate system, a workpiece coordinate system and other coordinate systems, derive the matrix transformation between the coordinate systems in detail, determine the tooth surface equations of the gear and pinion by generating surface and meshing equation. Analyse and compare the surfaces of diffrent parameters, determine the appropriate parameters to represent the tooth surface equations in order to facilitate its implementation in MATLAB, and provide the foundation for the follow-up model of spiral bevel gear.2.According to the tooth surface equations derived, calculate the points on the tooth surface with MATLAB, import the points into SolidWorks, create the tooth surface by programming using VB based on the technology of SolidWorks API, build an accurate three-dimensional models of the gear and pinion, and assemble them by meshing relationship. With VB programming, inspect the interpolation surface to ensure the error of the tooth surface meet the requirements of finite element analysis.3.With the accurate model of the spiral bevel gear, set up the finite element model in ANSYS. Get the ideal meshing density with meshing test and the ideal FKN by experiment, analyse the contact status of the spiral bevel gears at the same meshing lacatoin, obtain the curve of the changing contact area under the diffirrent load, analyse the tooth root stress of the pinion and gear, derive the contact stress and pricipal stress distribution curves along the tooth. Especially, get the functional relationship between the input torque and the torsion angle of the pinion firstly which can control a launcher accuratly. Study the meshing condition of the spiral bevel gears in a meshing cycle.4.Against the three kinds of error of the spiral bevel gears in the processing and installation process, analyse respectively the impact of the errorΔfAM of axial displacement of gear ring, the errorΔfA of the distance and the errorΔE∑of the angle between axis on the contact statue, stress and strain in the transmission process of the spiral bevel gears.