Abstract: An actuator for a magnetic head of a disk device has a rotating arm constructed of resin. The arm is supported rotatably in a housing on an electrically conducting shaft, and a magnetic head supported by a supporting member at one end of the arm is moved to various positions above the magnetic disk when the arm is rotated by a rotating mechanism. An electrically conducting mechanism conducts static electricity from the supporting member of the magnetic head to the shaft so that static electricity is prevented from accumulating on the head supporting member of the resin arm or in its vicinity.

Abstract: An arm unit for a hard disk drive is made by assembling together a plurality of stacked arms, a bearing member for supporting the arm unit upon a pivot shaft, and a coil for providing a magnetic force to swing the arm unit around the pivot shaft. Spacers are provided between the arms, and structural are provided for maintaining gaps between the arms and the spacers. Holes formed in the arms and in the spacers receive the bearing member while maintaining a predetermined gap. These assembled elements are then arranged within a mold and are fixed together into one unitary body by resin injected into the mold. By this construction, the assembly of the unit into the mold is facilitated, and the manufacturing cost of the arm unit is reduced.