基于圆弧啮合线内啮合齿轮设计与特性分析

Design and analysis of internal gear drive with arc contact path

针对内啮合齿轮传动,提出1种基于圆弧啮合线的大重合度内啮合齿轮构造方法。选取连接外齿轮和内齿圈节圆交点和齿顶圆交点的圆弧为啮合线,构造在该啮合线上共轭的外齿轮和内齿圈齿顶齿廓;根据共轭原理设计与齿顶齿廓共轭的齿根齿廓,完成内齿圈齿根齿廓修形;对新齿形进行根切检验,分析新齿形啮合几何特性及加载接触;利用数控加工方法完成内啮合齿轮样件的加工并进行啮合试验。研究结果表明:新齿形不产生根切和齿顶干涉;与渐开线内啮合齿轮相比,新齿形重合度大大提高,相对滑动率减小,相对法曲率增大;齿面接触和齿根弯曲应力显著降低,承载能力大大提高;齿数比为38/53的新齿形存在7对齿接触,验证了新齿形的大重合度啮合。

A high contact ratio internal gear drive with arc contact path was proposed for internal gear transmission. The circular arc connecting the intersection point of addendum circles and the intersection point of pitch circles was chosen as the path of contact. The addendum tooth profiles of pinion and internal gear conjugated with each other were constructed based on the given path of contact. According to gearing theory, the dedendum tooth profile was designed as conjugate curve of the addendum tooth profile of the mating gear and modification of dedendum tooth profile to internal gear was carried out. Geometric properties analysis and loaded contact analysis of the novel internal gear were also carried out. The results show that undercutting and addendum interference do not occur for the novel internal gear. The novel internal gear drive has higher contact ratio, smaller sliding ratio, but bigger induced curvature compared with the involute internal gear drive. The stress, especially the bending stress of the novel high contact ratio internal gear drive decreases remarkably. The novel high contact ratio internal gear with tooth number of 38/53 has 7 tooth being in meshing, which confirms the high contact ratio for the novel internal gear drive.