Equal height spiral bevel gear has complex tooth surface structure and strict meshing conditions, so its three-dimensional modeling and design is very difficult. At present, many CAD modeling software use the modeling curve in the plane to replace the spatial curve, resulting in a certain modeling error in the established contour spiral bevel gear model, and the parameter elimination model obtained by CAD modeling software has the problems that the model details cannot be edited and modified. Therefore, many engineers will use manual modeling to model in CAD and other software.
There are many modeling methods of equal height spiral bevel gears. Modeling based on the three-dimensional geometric relationship of gears is a relatively simple modeling method. Xu Jinli et al. W took the main reducer of a vehicle as an example, deduced the parameter equations of spherical involute and extended epicycloid (two-dimensional plane) of equal height teeth, obtained the corresponding curves in the modeling module of UG in the form of expression, and trimmed the spherical involute and extended epicycloid based on the formation principle of tooth profile, The cogging entity is obtained by fitting and stitching the surface, and finally the three-dimensional solid model of equal height teeth is obtained. Fig. 1 shows the modeling curve and gear model of three-dimensional geometric relationship modeling. Wang et al. Obtained the three-dimensional solid model of equal height spiral bevel gear through Pro / E modeling software, and established a certain correlation between the three-dimensional solid model and modeling parameters through internal modeling program, so as to obtain the three-dimensional model of equal height gear conveniently. However, this method has the problem of difficult editing modeling parameters. Li Qiang and others used Pro / E modeling software to model the three-dimensional solid model of equal height teeth based on the relevant modeling parameter standards of the gear manual, and realized the meshing transmission between the driving and driven gears.
In the modeling research of equal height spiral bevel gear, the modeling method based on the machining principle and machining technology of gear is more commonly used. Based on the machining principle of equal height spiral bevel gear and the relationship between the coordinate system of milling cutter head, machining machine tool and gear workpiece, Yu Xiangyu established the tooth surface structural equation of equal height gear, and reflected the three-dimensional solid model of equal height gear through CAD modeling software. Based on the local synthesis method and tooth contact analysis (TCA) technology, Zhang Hua and others studied the tooth profile, tooth surface structure and machining parameters of equal height teeth, and obtained the three-dimensional solid model of equal height teeth through UG modeling software. Lin et al. Constructed the three-dimensional geometric model of equal height teeth based on the principle of mechanical cutting, and reconstructed the tooth surface based on the meshing principle to increase its tooth surface accuracy. Baiyang et al. M constructed the geometric model of the production wheel by studying the mechanical cutting principle of equal height teeth, and completed the mechanical cutting simulation modeling model of equal height teeth through UG modeling software.
Due to the disadvantages of manual modeling, such as high labor intensity, low modeling accuracy and inability to realize gear standardization, based on the mechanical cutting principle of equal height teeth, many researchers turn to the automatic modeling direction of equal height teeth and use secondary development tools for three-dimensional solid modeling of equal height teeth. By studying the mechanical cutting principle and geometric structure design theory of equal height teeth, Wang Qingyun deduced and established the geometric design algorithm and crown tooth surface equation of equal height teeth. Taking Visual Basic 6.0 modeling language as the secondary development tool, Wang Qingyun compiled the simulation module of computer modeling programming system of equal height spiral bevel gears. Tan et al. Designed the tooth profile section of equal height spiral bevel gear through computer-aided design and analysis, which significantly improved the contact characteristics of tooth surface. Yang et al. Based on the meshing principle of gears, obtain the actual contour tooth profile through MATLAB software, process the data obtained from MATLAB workspace with the help of Excel, and then obtain a complete contour tooth model in AutoCAD software.