Data storage system having a positive actuator latching assembly

Abstract

A multiple disk drive storage system includes a latch assembly for positively latching a head positioning actuator arm when the head is positioned on a load/unload mechanism at the outer perimeter of the disks. Latching and unlatching cycles of the latch assembly are effected by interaction of the actuator arm motion and a latch arm retention magnet structure. In the latch position, the actuator arm is mechanically captured by a hook shaped latch head at one end of the movable latch arm, so that, even in a power off condition the actuator arm is positively latched by the combination of the actuator arm motion limitations, the latch head shape, the latch arm motion limitations and a bias spring urging the hooked latch head into a permanent, static latch with the actuator arm. The opposite end of the latch arm is provided with a magnetic mass which is attracted and held by the retention magnet. This magnet when the activated when the actuator arm is driven from a latching position toward a pre-reset position preparatory to releasing or unlatching the actuator arm. After the opposite end of the latch arm is captured by the magnet, the actuator arm motion is released. The reset portion is disposed such that when struck by the actuator arm, the latch arm opposite end is released from the retention magnet, allowing the bias spring to return the latch arm and head to a rest position, ready to capture the actuator arm upon initiation of a subsequent latch cycle. The latch is now freed to rotate over the disk surfaces in its normal read/write function mode.