Patent ID: 6954017

Claim:
A motor comprising: a column-shaped shaft extending in a vertical direction; a sleeve impregnated with oil, which is cylindrical and rotatably supports the shaft therein, a sleeve-type bearing being formed between the shaft and the sleeve; a rotor provided with a disc-shaped portion expanding from an upper end portion of the shaft about the shaft, a cylindrical portion hanging downwardly from an outer peripheral edge of the disc-shaped portion, and at least two peripheral wall portions, an inner wall portion and an outer wall portion, which are hanging downwardly from the lower face of the disc-shaped portion toward the upper end of the sleeve about the shaft so as to surround the shaft, and are spaced from each other in a radial direction of the shaft; a housing having a cylindrical sleeve holding portion holding the sleeve inside thereof; a stator fixed outside of the sleeve holding portion; a cylindrical magnet which is fixed on the inner peripheral face of the cylindrical portion so as to be opposed to the stator for generating a rotational driving force in the rotor together with the stator; and an annular recessed portion located in an outer peripheral location of the outer wall portion so as to surround an open space over the sleeve, the open space in which the inner and the outer wall portion are accommodated, for preventing oil from leaking out, the annular recessed portion having a lower top of the most inner part, wherein the lower end of the inner wall portion is located lower than the lower end of the outer wall portion, and the lower end of the outer wall portion is located lower than the lower top of the annular recessed portion.