周转轮系传动比计算的标注方向法

he epicyclic gear train speed ratio calculation belongs to the university teaching material content. The actual teaching materials apply the classical absolute direction method. To the epicyclic gear train whose all axis aren't parallel, it is difficult to judge the absolute direction. The label direction method is presented. In the changed gear train, the direction of each gear is labeled according to the transmission relation. Then the speed ratio value formula is gotten according to the fixed axial gear train. If the calculating value of a gear is negative, its real rotating direction is opposite to the label direction. The calculating example proves the simplify and validity of the presented method. So it can supplement the teaching material.