Patent ID: 6556374
Filing Date: 2003-04-29
Classification: G11B

Abstract:
An apparatus for rotating at least one disk in a disk drive, comprising:a motor shaft; a bearing sleeve; two ball bearings positioned between an outer periphery of said motor shaft and an inner periphery of said bearing sleeve, wherein each of said ball bearings includes a plurality of balls; a hub having an inner periphery with only one bonding region, said bonding region having at least one annular recess and a plurality of contact regions, wherein said bonding region is positioned axially between said two ball bearings without being axially aligned with either of said two ball bearings and between an outer periphery of said bearing sleeve and said inner periphery of said hub, wherein an internal diameter of said hub at one of said annular recesses within said bonding region is greater than an internal diameter of said hub at each of said plurality of contact regions within said bonding region by at least a distance, said distance equals two times an outer diameter of said bearing sleeve multiplied by an operating temperature range of said apparatus multiplied by the differences between a coefficient of linear expansion of said hub and a coefficient of linear expansion of said sleeve; and a magnet attached to said hub and disposed outwardly of said bearing sleeve.