Patent ID: 6606223
Filing Date: 2003-08-12
Classification: G11B

Abstract:
A voice coil motor for use in a data storage device comprising:a first pole piece having an inner surface; a second pole piece having an inner surface, the second pole piece operably connected to the first pole piece so that the inner surface of the second pole piece is held in spaced relation with the inner surface of the first pole piece such that a gap is defined therebetween; a dummy magnet formed from a portion of the second pole piece, the dummy magnet having a depth equal to the depth of the second pole piece and protruding from the inner surface of the second pole piece into the gap, the portion of the second pole piece formed into the dummy magnet has a recessed outer surface relative to an outer surface of the second pole piece and a protruding inner surface to form an inner surface of the dummy magnet; a permanent magnet in the gap on the inner surface of the first pole piece; and a voice coil in the gap between the dummy magnet and the permanent magnet.