Patent ID: 7023657

Claim:
A hard disk drive comprising: a housing comprising a base plate and a cover plate provided with a through hole; a spindle motor comprising a shaft which is supported on the base plate and the upper end of which is joined to the cover plate by a screw inserted through the through hole, and a hub installed around the outer circumference of the shaft to be rotatable; at least one data storage disk joined to the outside of the hub and capable of being rotated together with the hub; a head assembly for recording data onto the disk and reading recorded data from the disk; and a damper having at least a portion disposed in the hole so as to be interposed between the screw and the cover plate, the damper comprising at least one viscoelastic material layer, the damper having multiple layers which are stacked in a direction from the screw to an inner circumferential surface of the through hole, such that an inner most layer of the damper contacts the screw without contacting the inner circumferential surface of the through hole; and an outermost layer of the damper contacts the inner circumferential surface of the through hole without contacting the screw, wherein the damper restrains vibrations generated by the spindle motor from being transferred to the cover plate, thereby reducing noises, and wherein the damper damps the vibrations, thereby reducing fluttering of the disk.