谐波齿轮传动重合度的计算方法研究

Research on computing method of contact ratio for harmonic gear drives

针对谐波齿轮传动的特殊性提出谐波齿轮重合度的定义,即柔轮和刚轮轮齿的啮合区间角与刚轮单个齿距圆心角的比值。基于瞬心线运动几何学,推导出柔轮和刚轮轮齿的相对瞬心线方程,然后根据Willis定理的结论,计算出柔轮和刚轮之间的啮合区间角,最后由重合度定义计算出重合度。此计算方法适用于各种不同齿形的谐波齿轮传动重合度的计算,对于衡量新齿形谐波齿轮传动的啮合性能,具有重要的参考意义,因此该方法具有通用性。

Specific to the particularity of harmonic gear drives,definition for contact ratio of the drives is put forward in it,namely the ratio of meshing angle between the teeth of flexspline and rigid gear to central angle of single pitch of rigid gear.And relative instantaneous center equation for the tooth of flexspline and rigid gear is deduced based on kinematic geometry of instantaneous center curve,and then meshing angle is computed according to conclusion of Willis theorem.Finally contact ratio is computed by the definition,which is suitable for computing contact ratio of different kinds of the tooth profiles of harmonic gear drives.It is significant in providing reference for measuring meshing performance of new tooth shape of harmonic gear drives with its generality.