US Patent 7062814 Inflatable column assembly for a dock leveler

A dock leveler for a truck loading dock includes a pivotal deck that is actuated by an inflatable column assembly. The inflatable column assembly includes a pliable tube that when inflated has a generally vertical cylindrical shape that can provide a heavy deck with substantial columnar support. The shape and orientation of the column assembly is such that the lengths of the pliable tube's seams are minimized. A pliable fabric sheet held in tension against the underside of the deck provides a generally flat, broad surface against which the pliable tube can push as the inflatable column assembly pushes the deck upward. A footed pallet underneath the pliable tube can be banded to the deck during shipment. After installation, the pallet can be readily lifted for cleaning the pit floor underneath the pallet.