US Patent 7316446 Supporting part of a vehicle door

A vehicle door has a supporting annular frame 12-19 of high strength steel close to the outer panel and the frame is stamped from a plane sheet so that a side impact guard beam (20) is formed in the same stamping operation. Both the annular frame and the side impact guard beam have hat-formed cross section, and reinforcement plates (21, 22) couple together the outer and inner flanges (26, 27) and give the frame a closed cross section at the connections of the side impact guard beam to the annular frame. The outer side flange (26) of the annular frame carries the outer panel of the door, and the other elements of the door are screwed on the frame 12-19 at the interior side of the frame.