齿轮的变位可以提高其承载能力,并且扩大齿轮传动几何尺寸和运动配合范围的可能性。在设计变速箱和行星机构时,应用封闭图来选择变位系数ξ,将使工作量大为简化。对每一齿轮付而言,封闭图可直接选择变位系数,以满足对传动提出的要求和啮合条件。利用封闭图可显著地缩减设计计算工作和错误的几率。对于含有同时与两个或几个其他齿轮相啮合的耦合齿轮的机构而言变位系数的选择是相当复杂的。例如,广泛应用的同心单级 The displacement of the gear can increase its carrying capacity and increase the possibility of gear transmission geometry and range of motion fit. In the design of transmission and planetary gear, the use of closed map to select the displacement coefficient ξ, will greatly simplify the workload. For each gear, the closed graph can directly select the displacement coefficient to meet the requirements and meshing conditions of the transmission. Using a closed graph can significantly reduce the chances of designing calculations and errors. The choice of displacement coefficient is quite complicated for a mechanism containing a coupling gear that meshes with two or more other gears at the same time. For example, a widely used concentric single stage