US Patent 7284626 Patient support apparatus with powered wheel

A patient support apparatus has a lower frame and an upper supported above the lower frame and movable relative to the lower frame. A plurality of casters are coupled to the lower frame. A wheel is movable relative to the lower frame between a lowered position engaging the floor and a raised position spaced from the floor. A drive assembly is coupled to the wheel and is operable to drive the wheel to propel the patient support apparatus along the floor. A foot pedal is coupled to the lower frame and is movable to raise and lower the wheel relative to the floor. Elevation adjust pedals are coupled to the lower frame and are movable to change an elevation of the upper frame relative to the lower frame.