LATCH MECHANISM FOR DISK DRIVES

A latch mechanism (146) for locking an actuator arm (160) in a disk drive (36) includes a latch (184) pivotably supported in the disk drive for engaging the actuator arm and an electromagnet (183) for capturing and holding the latch to disengage the latch from the actuator arm. A spring (188) is provided to bias the latch to engage with the actuator arm. A swivel plate (194) is provided on the latch mechanism and the electromagnet captures the swivel plate; in particular, the electromagnet has two poles, (190a and 190b) and the swivel plate contacts one of the poles and an air gap exists between the swivel plate and the other pole. The air gap allows the electromagnet to release the swivel plate. The swivelling action of the swivel plate causes the swivel plate to seat with the entire surface of the one pole of the electromagnet, increasing the ability of the electromagnet to hold the swivel plate once the swivel plate has been captured.