US Patent 7043789 Foldable ramp and method for its manufacture

A foldable ramp, typically a portable foldable ramp for use in allowing access to wheelchairs up and down steps and/or into and out of vehicles. The ramp has two track members that each have a channel formed along their elongate sides that face each other when the ramp is unfolded. A series of first hinge elements is retained in one channel and a series of second hinge elements retained in a second channel. Each element of the series of first hinge elements is arranged to cooperate with at least one element of the second series, so that the first and second hinge elements are arranged alternately in the ramp to provide a hinge connection between the elongate sides of the first and second track members.