基于AutoCAD渐开线直齿圆柱齿轮的自动三维建模

Automatic creation of three dimensional model of involute cylindrical gear based on autoCAD

渐开线圆柱齿轮三维建模的重点和难点在于轮齿端面轮廓的绘制。利用渐开线的参数方程式并通过AutoLISP编程绘制出端面齿廓一侧的渐开线;在对轮齿端面齿廓进行几何分析与计算的基础上,确定并绘制出其对称线及齿顶圆弧,并利用该对称线通过镜像获得轮齿端面齿廓另一侧的渐开线。然后利用AutoCAD的"复制"、"画圆"、"裁剪"、"多段线编辑"、"阵列"、"拉伸"等命令实现圆柱齿轮的三维建模。

<Abstrcat>The key and difficulty on creating three dimensions model of involute cylindrical gear is drawing of transverse tooth profile. By means of parameter equation of involute and programming of AutoLISP,the involute on one side of transverse tooth profile was drawed out. On the basis of analyzing and calculating transverse tooth profile for geometry, the symmetry line and tip arc of transverse tooth profile for a teeth of gear were defined and it also be drawed out. It get opposite involute of transverse tooth profile with the aid of the symmetry line. Afterwards, by using the commands 'Copy','Circle','Trim','Pedit','Array','Extrude' of AutoCAD, three dimensional modeling of cylindrical gear is achieved.