| 摘要 |
A brushless DC electric fan cools an information handling system with reduced audible noise by skewing a seam in a permanent magnet relative to a rotation axis of the fan. For instance, the permanent magnet is formed from a sheet of magnetic material having a parallelogram shape. The parallelogram is rolled into a cylindrical shape having a seam skewed relative to the axis of rotation of the cylinder. The discontinuity in the magnetic field is moderated by passing the seam through the magnetic field over several degrees of rotation, such as approximately ten degrees.
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