Hard disk drive having air pumping groove

摘要

In a hard disk drive, at least one groove is formed in any one of surfaces of the base plate and the cover plate which faces the disk to pump air toward an outer circumferential side of the disk, an outer end of the groove is located at a position inwardly separated a predetermined distance from an edge of the disk such that an air journal zone having a predetermined width is formed along a circumferential direction of the disk between the outer end of the groove and the edge of the disk. The groove is formed in multiple numbers in a circumferential direction of the disk at a predetermined interval and is extended in a radial direction from an inner circumferential side of the disk and curved in a direction in which the disk rotates. Thus, vibration of the disk is reduced by a damping operation of compressed air pumped by the groove and having a high pressure in the air journal zone.