Differential Gear Unit

摘要

A differential gear unit divides an input driving force into first and second outputs, and permits a difference between the first and second outputs. The differential gear unit includes a differential case serving as a casing that defines an internal space and an opening communicated with the internal space and that is rotatable in a given direction and an opposite direction. The differential case includes a flange portion as an input portion to which the driving force is input. The differential case is configured such that the fatigue life of the differential case when the driving force is repeatedly input in the flange portion in the direction R 1 is longer than the fatigue life of the differential case when the driving force is repeatedly input in the flange portion in the opposite direction; R 1 is the rotational direction in which the vehicle runs forward.