平行轴变传动比齿轮数字设计方法

Digital design method of parallel-axis variable ratio gear

为解决平行轴变传动比齿轮副关键零件变传动比齿轮的设计问题,提出一种全新的数字设计方法。该方法综合考虑齿轮副中定传动比齿轮的变位、基圆与齿根圆的位置关系,以及齿轮副的啮合遍历、顶隙等设计因素,将定传动比齿轮看作由无数个垂直于其轴线的无限接近的平面截切其实体后得到的截平面的集合,每一个截平面称为一个齿轮元;假设过变传动比齿条齿坯顶面上任一点有一条平行于齿轮副基圆圆心连线的随动直线,传动时该直线与对应齿轮元集产生一系列交点,此点处的齿廓高度值即为交点高度值中的最小值。建立了求解变传动比齿轮齿廓点高度值的数学模型,开发了齿廓点云的求解算法,得到了变传动比齿轮齿廓点云。通过对试制的样件进行传动误差及传动稳定性的相关测试验证了该方法的有效性。

To solve variable ratio gear design problem of parallel-axis variable ratio gear pair, a new digital design method was proposed. By considering the design factors such as modification of constant ratio gear, relationship be- tween base circle and dedendum circle, meshing traversal and tip clearance of gear pair, the constant ratio gear was taken as a set of cutting planes obtained by using countless planes perpendicular to the axis to cut the gear, and each cutting plane was called a gear element. Assuming there was a line through a point on the variable ratio gear billet top land and parallel to the connecting line between two base circle centers of gear pair, it would generate a series of intersections between this line and the corresponding gear elements, and the altitude value of arbitrary tooth profile point was the minimum of all intersection values. The mathematical model to solve the altitude values of variable ratio gear tooth profile points was established and the corresponding solution algorithm was developed. Tooth profile point cloud of a variable ratio gear was obtained based on this method, and relevant tests of transmission error and transmission stability on the sample were performed. The experimental results verified the effectiveness of the proposed method.