Provided is a power transmission device for which there is no risk of the driving member breaking. The device has a stepping motor (driving member) (61a) that operates based on command signals from a control unit (70), a lead screw (61c) that is rotated with operation of the stepping motor (61a), and a power transmission unit (65) that moves in axial direction (X) of the lead screw (61c) as a result of rotation of the lead screw (61c) and transmits power to a power transmission receiving unit (42e). The control unit (70) performs control to stop output of the command signals to the stepping motor (61a) when the power transmission unit (65) is not moving in the axial direction (X).
