Abstract: There are provided a base structure for a device such as a hard disk drive and a hard disk drive having the same. The base structure includes: a base body including components mounted thereon and made of a non-aluminum material; and a base reinforcing part attached to the base body as an additional piece. More specifically, the base body is provided by press-molding a steel sheet and the base reinforcing part is provided by press-molding a steel sheet or is provided as a reinforcing plate separately attached to an outer surface of the base body, and the base structure further includes a reinforcing part processing member additionally provided in the reinforcing plate. The base structure for a device such as a hard disk drive and the like, in which the rigidity thereof is secured or the weight thereof is reduced by using various base reinforcing parts and reinforcing part processing members while the manufacturing costs of the base structure are reduced.

Abstract: Disclosed herein is a spindle motor having a fluid dynamic bearing as an oil gap formed between a rotator and a stator, wherein the stator includes a sleeve having a protruding part extending in a circumferential direction formed on the upper part thereof, the rotator includes a hub including an oil interface forming member positioned under the protruding part of the sleeve and coupled to the lower end thereof, and an oil interface of the oil gap is formed between the upper part of the oil interface forming member and the lower part of the protruding part of the sleeve.