In-spindle motor assembly for disk drive and method for fabricating the same

摘要

An in-spindle disk drive motor incorporating a novel two-piece aluminum spindle and a method for fabricating the same. The spindle is hollow and contains a removable steel flux sleeve on which plastic permanent magnets are mounted. The spindle is mounted by means of two bearings to a non-rotating stator shaft disposed through the center of the spindle and rigidly attached to a disk drive base. One of the bearings is located in a removable bearing sleeve at the top of the spindle and the other is located beyond the steel sleeve at the bottom end of the spindle. The aluminum spindle eliminates thermal distortion effects caused in prior art in spindle motors by thermal expansion differences between aluminum disks and non-aluminum spindles.