Abstract: A motor having a motor shaft rotatable about a motor axis; a power transmission having gears and connected to the motor shaft; a housing having a motor housing portion accommodating the motor and a gear accommodation portion accommodating the power transmission; a fluid contained in the housing; and a fluid channel through which the fluid flows, in which a reservoir storing the fluid above the motor axis is provided in the inside of the gear accommodation portion. The fluid channel includes an external supply channel for supplying the fluid from an outside of the motor to the motor, and an internal supply channel for supplying the fluid to a hollow portion of the motor shaft. The reservoir has a first supply port and a second supply port. The external supply channel is connected to a first supply port. The internal supply channel is connected to a second supply port.