US Patent 7159261 Convertible dock ramp

A convertible dock ramp has an upper end for being pivotally mounted to a mounting structure, and a lower end for resting on a second structure. The convertible dock ramp includes a pair of spaced-apart side frames each including upper and lower rails; and a plurality of steps each including a tread surface. The steps are pivotally mounted between the side frames such that the tread surfaces remain substantially parallel to each other as the side frames pivot about the upper end. The steps are pivotable between: a ramp configuration in which the tread surfaces collectively form a substantially flat ramp surface; and a stair configuration in which the tread surfaces collectively form a staircase-like structure. A changeover mechanism selectively retains the convertible dock ramp in the ramp configuration or the stair configuration. A safety stair tread deflects upward as needed to prevent trapping a user's foot.