Disk drive having reduced magnetic flux leakage
AssigneeKabushiki Kaisha Toshiba
InventorMichael C. MCGRATH
Life of this patent
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Abstract
In a voice coil motor (VCM) of a disk drive, a coined feature formed on a ferromagnetic plate reduces magnetic flux leakage from a disk drive without increasing the weight of the drive or adding complexity to the manufacturing process. The coined feature is shaped and positioned to alter the path of magnetic flux lines produced by the VCM in a way that significantly reduces the flux leakage from the VCM. The coined feature may be formed without adding material to the ferromagnetic plate by the same stamping process used to fabricate the plate.
Claims20
A disk drive comprising:
- a storage disk;
- an actuator arm assembly including a transducer element using which data is read from and written to the storage disk;
- and
- a voice coil motor for positioning the actuator arm assembly, the voice coil motor including a ferromagnetic plate on which at least one magnet is mounted, the ferromagnetic plate having a coined section that:
- (i) has substantially the same thickness as other parts of the ferromagnetic plate, (ii) projects away from said at least one magnet, and (iii) is positioned near a neutral zone of said at least one magnet.
A voice coil motor for a disk drive, comprising:
- a first ferromagnetic plate on which a magnet is mounted;
- and
- a second ferromagnetic plate on which a magnet is mounted,
- wherein the first ferromagnetic plate has a stamped section that:
- (i) has substantially the same thickness as other parts of the first ferromagnetic plate, (ii) projects away from the magnets, and (iii) is positioned near a neutral zone of the magnets.
A voice coil motor for a disk drive comprising at least one magnet mounted between a pair of ferromagnetic plates, one of the ferromagnetic plates having a stamped section formed therein proximate the neutral zone of said at least one magnet, wherein the stamped section is configured to project away from said at least one magnet and add minimal reluctance to the magnetic flux flow.
Dependencies are inferred from the claim text.