A motor of this invention is provided with a sleeve-type bearing impregnated
with
oil for supporting a rotor assembly including a shaft and a rotor member. A lower
face of the rotor is provided with at least two peripheral wall portions, an inner
peripheral wall portion and an outer peripheral wall portion, which surround the
shaft with a gap therebetween in a radial direction. The peripheral wall portions
are accommodated in an annular recessed portion so as to surround an open space
over a sleeve constituted the sleeve-type bearing and has a lower top of the most
inner part. The lower end of the inner peripheral wall portion is located lower
than the lower end of the outer peripheral wall portion, and the lower end of the
outer peripheral wall portion is located lower than the lower top of the annular
recessed portion.