Driving force transmission apparatus, and four-wheel-drive vehicle including the driving force transmission apparatus

摘要

A driving force transmission apparatus includes a cam mechanism that converts motor torque from an electric motor into first cam thrust force and second cam thrust force. The cam mechanism includes: a cam member that rotates upon reception of the motor torque from an electric motor; a rolling member that rolls on the cam member; and a retainer that outputs the first cam thrust force and the second cam thrust force toward a multiple disk clutch as the rolling member rolls. The rotation of the retainer around a rotation axis is restricted, and the retainer moves in a direction of the rotation axis while retaining the rolling member such that the rolling member is rollable.