Tooth saturation for reduced electromagnetic harmonics
AssigneeSeagate Technology LLC
InventorsTan H. Pham, Klaus D. Kloeppel, Donald J. Macleod
Life of this patent
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Abstract
The tooth saturation level is improved and electromagnetic harmonics reduced by reducing the path cross-section of area in the tooth with a geometrical means such as punched holes through the stator laminations. The punched holes alter the magnetic flux pattern by forcing the flux to go around the holes, providing a greater concentration of the flux within regions of the teeth, as well as, depending on the position of the hole along the long axis of the tooth, redistributing the flux density in the air gap. This redistributed flux density will also reduce the harmonics to improve the electromechanical device electromagnetic performance.
Claims16
A motor having improved tooth saturation comprising a stator comprising a plurality of teeth extending radially toward a surrounding rotor, and a rotor supporting a magnet which electromagnetically interacts with the stator, the stator comprising an inner yoke and a plurality of teeth extending radially toward the magnet and having a shoe portion at a distal end thereof from the stator yoke, each of the stator teeth having a hole punched there through at or near a central radially extending axis of the tooth, the hole being disposed between the inner yoke and shoe portion, the hole being a predetermined size selected to effect the saturation of the tooth when windings on the tooth are energized.
A motor having improved tooth saturation comprising a stator comprising a plurality of teeth extending radially toward a surrounding rotor, and a rotor supporting a magnet which electromagnetically interacts with the stator, the stator comprising an inner yoke and a plurality of teeth extending radially toward the magnet and having a shoe portion at a distal end thereof from the stator yoke and means disposed between the inner yoke and shoe portion for altering the saturation of the teeth with rotation of the magnet to smooth a back EMF electromagnetic force waveform.
Dependencies are inferred from the claim text.