Technique making vehicle bumper front panel reinforced by rear ribs, involves injection molding followed by removal of molding and then injection of gas into T-intersections between ribs and panel, forming longitudinal void

摘要

Material is injected into the mold to form the bumper (10) front panel (12) connected to rear reinforcement ribs, with longitudinal gas openings; it is then extracted. Seconds after injection, high pressure gas is forced into the openings, expanding longitudinal voids in the connecting region, where ribs and panel intersect at T-junctions. An Independent claim is included for the vehicle bumper (fender) so produced.