Patent ID: 8111484

Claim:
In a hard disk drive having a base, a read/write head, an actuator arm carrying the read/write head and supported so as to be rotatable relative to the base in a first direction of rotation between a parking position at which the read/write head is parked and a read/write position at which the read/write head performs a read/write operation, a bobbin integral with and extending from a rear end of the actuator arm so as to rotate with the actuator arm, a VCM magnet of a voice coil motor (VCM) juxtaposed with the bobbin, and a coil of the VCM disposed on the bobbin, an actuator latch mechanism comprising: a latch lever including a latch arm supported so as to be movable relative to the base between a latching position and an unlatching position, wherein the latching position is one at which the latch lever prevents the actuator arm from rotating in the first direction from the parking position to the read/write position, and the unlatching position is one at which the latch lever allows the actuator arm to rotate in the first direction from the parking position to the read/write position; and a magnetic latch supported by the latch arm and positioned thereby such that while the actuator arm is in the parking position the magnetic latch interacts with magnetic field produced by the VCM magnet to generate a magnetic force of attraction which urges the latch arm towards the latching position, and interacts with the electromagnetic field produced by the VCM coil to generate a magnetic force which urges the latch arm towards the unlatching position.