Abstract: An interlock system is provided for removable-media drive unit to prevent the drive loader from attempting to pull in and mount a data cartridge before it is released by a mechanical gripper or human hand. The interlock system includes a light source and a photodetector positioned in front of the drive on opposite sides of the path cartridge takes when it is being inserted or removed from the drive loader. The presence of the cartridge, gripper or other object in the path interrupts a light beam from the light source thereby signalling the drive controller to disable the drive loader. When the gripper has released the cartridge and withdrawn, or when the path is otherwise clear, the photodetector again detects the light beam and signals the drive controller that the loader can be safely enabled. In one embodiment, the light source and photodetector are mounted on a card which plugs into the face of the drive.

Abstract: An automated storage library having the ability to store and manipulate data storage elements in three dimensions. Data storage elements such as tape cartridges are stored in storage compartments separated by low-friction downward sloping sliding planes each capable of holding a plurality of data storage elements. The automated storage library further includes a magnetic picker apparatus having two electromagnetic coils. In one embodiment, the two coils are energized simultaneously with the first coil used to reposition an L-shaped flipper. This flipper raises a roller gate positioned at one end of a storage compartment to release a stored data storage element. The second electromagnetic coil supplements the gravitational pull on the data storage element by attracting a steel strip on the face of the data storage element and an associated coil carriage retrieves the data storage element from the compartment.