US Patent 9233647 Shelving system with a ladder cage

A ladder cage is provided. The ladder cage includes opposite first and second sidewalls each extending parallel to a longitudinal axis. Spaced apart brackets are coupled to one of the sidewalls. Spaced apart rollers extend between the sidewalls. The rollers are each rotatable relative to the sidewalls along a rotation axis that extends transverse to the longitudinal axis. The rollers and inner surfaces of the brackets and the sidewalls define a housing configured for disposal of a ladder.