Abstract
In some hard disk drives (HDDs), the voice coil motor (VCM) has only a single-sided magnet in order to reduce the cost. In these HDDs, the bending vibration of the actuator coil at low frequency disturbs the positioning control of the magnetic head. We explain here that the cause of the bending vibration was due to the plane perpendicular to the pivot axis of the magnetic field in the outer coil with bending magnetic flux. We also propose a flux guide mounting that diverts the magnetic flux from the outer coil in order to reduce the coil bending excitation force.
