Patent ID: 7537267

Claim:
A hatchback door structure for vehicles, comprising: an inner panel which is arranged on an inner side of a vehicle; and an outer panel which is arranged on an outer side of the vehicle; wherein the inner panel is formed as an integral unitary member by press-forming; and wherein the inner panel comprises: a frame which has a shape outlining an outer shape of the hatchback door structure, hinges provided on an upper periphery of the frame for attaching the hatchback door structure to a vehicle, and a pair of stiffening ribs which are integrally formed with the frame, said stiffening ribs extending approximately in a V-shape from a bottom part of the frame to each of a couple of side portions of the frame, wherein: on an upper side of the stiffening ribs, a substantially pentagonal first opening is defined by the stiffening ribs and the frame; on a lower side of one of the stiffening ribs, a substantially triangular second opening is defined by the one of the stiffening ribs and the frame; and on a lower side of the other stiffening rib, a substantially triangular third opening is defined by the other stiffening rib and the frame.