Patent ID: 7162762

Claim:
A dock leveler for forming a bridge between a floor of a loading dock and a trailer, said dock leveler comprising: a deck assembly including a deck, a rear hinged end, a front end, a lip and a deck lift arm, said deck lift arm being secured to and extending downwardly from said deck assembly proximal said rear hinged end, said deck lift arm having a lower end downwardly spaced from said hinged end, said deck being pivotally secured at said rear hinged end, and lip being pivotally secured to said front end, and said deck assembly being movable through a range of inclined positions between raised and lowered positions; an air lift assembly including an inflatable bag, an air supply unit, a bag support and a drive platform, said bag forming an expandable chamber positioned between said bag support and said drive platform, said air supply unit having an exhaust port in air delivering communication with said bag and being selectively activated to supply air to said chamber and inflate said bag, said drive platform being movable from a retracted position when said bag is in a collapsed condition to an extended position when said bag is in said inflated condition, said drive platform remaining substantially horizontal and aligned directly above said bag support, and said air lift assembly being biased toward said retracted position when said air supply unit is deactivated; a deck lift assembly including a pull line engaged with said drive platform and said lower end of said deck lift arm; and, wherein activating said air supply unit inflates said bag, pushes said drive platform and pull line upward, draws said lower end of said lift arm forward, and pivots said deck assembly toward said raised position.