US Patent 7350856 Foldable chair

A foldable chair includes a leg unit, a seat unit supported on the leg unit, a pivot unit including two pivot joints secured to the leg unit, and a backrest unit including two opposite backrest rods that are pivoted to the leg unit through the pivot joints, respectively. The backrest unit is rotatable relative to the leg unit between a folded position, in which the backrest unit overlaps with the seat unit, and an extended position, in which the backrest unit stands upright from the seat unit.