Patent ID: 7428741
Filing Date: 2008-09-23
Classification: G11B

Abstract:
1. An optical storage, comprising; a housing defining therein a space; a disk received in the space; a base defining a bottom of the housing; a drive unit mounted on the base for turning the disk around a drive axis; a shroud defining a side wall of the housing and having a curved portion, the curved portion being expanded outwardly away from the disk; a bump projecting from the base toward the disk along a circle concentric with the drive axis for reducing shear stress generated at a circumference of the disk due to the rotation of the disk; and a cover defining a top of the housing; wherein the cover has a slanted, circumferential portion extending from a central portion of the cover toward the shroud at an upward inclination with respect to a disk plane of the disk when seen in a cross-section taken along a line perpendicular to the disk plane, so that a central height from the disk plane to the central portion of the cover on the drive axis is smaller than a circumferential height from the disk plane to the cover at the shroud, whereby flow resistance to the rotation of the disk is reduced to reduce power consumption.