A dynamic pressure bearing is defined in a first gap between a shaft portion and a sleeve portion. An upper seal portion extending upward and a lower seal portion extending downward are arranged radially outward of the dynamic pressure bearing. Each of the upper seal portion and the lower seal portion includes a surface including a lubricating oil located therein. The upper seal portion and the lower seal portion are arranged in communication with each other through a communicating hole defined in the sleeve portion. The communicating hole and a space ranging from the upper seal portion to the lower seal portion through the first gap are filled with the lubricating oil. The axial distance between the surfaces of the lubricating oil in the upper seal portion and the lower seal portion is arranged to be shorter than the axial distance between an upper end and a lower end of the dynamic pressure bearing.