We have made certain that the reason of the splined spindle rapture is fatigue failure, its crack initiation lies in the minimal knuckle curvature radius surface region of the spline dedendum bottom.
初步确定了花键轴的断裂是疲劳断裂，裂纹源在花键齿根底部过渡圆角曲率半径最小的表面部位。
2
Because of the tooth thickness of the dedendum is larger than that of the common involute gear and the Pitchs do not contact each other, the beam strength and surface strength of tooth are increased.