Abstract: There is provided a base for a motor, the base including: a base body having a disk disposed thereon; an outer wall part defining an outer part of the base body; and at least one rib depressed from one surface of the base body and protruded toward the other surface thereof to thereby improve rigidity of the base body, wherein pressure in an inner edge of the rib is equal to or greater than pressure in an outer edge thereof at the time of rotation of the disk.

Abstract: A hard disk drive including a base portion, a motor-hub assembly to which at least one disk is coupled, the motor-hub assembly coupled with the base portion and an airflow shroud coupled with the base portion. The airflow shroud including an airflow inlet oriented parallel to the disk and an airflow outlet oriented perpendicular to the disk. In so doing, the airflow shroud reduces vibration of a rotating disk in a hard disk drive.

Abstract: Embodiments of the present invention help to prevent leakage of low-density gas during low-density gas injection into a disk drive device and to perform low-density gas injection efficiently. In a hard disk drive (HDD) according to one embodiment of the present invention, an injection hole filter with a valve function is attached to a helium injection hole in order to inject helium gas in an enclosure. The injection hole filter has a valve member configured to operate in an open state or closed state. The open state is a state while the helium gas is being injected and the closed state is a state after the helium gas has been finished to be injected. The valve member is in the open state if the outside pressure is higher than the inside pressure and is in the closed state if the inside pressure is higher than the outside pressure.

Abstract: An air pump for generating air pressure in a hard disk drive (HDD) including a rotor disposed inside the HDD. The rotor comprises a first air pressure generating feature. The air pump further includes a stator. The stator includes a second air pressure generating feature. The first air pressure generating feature corresponds with the second air pressure generating feature and the air pressure is generated at a location where the first air pressure generating feature rotates in proximity to the second air pressure generating feature.