Patent ID: 8376427

Claim:
A method for the manufacture of an energy absorber for a bumper assembly of a vehicle, comprising the steps of: providing a piece of sheet metal provided with opposite end edges and opposite side edges; deep drawing said piece of sheet metal to form transverse corrugations defining transverse grooves in one or more regions of the piece of sheet metal; longitudinally bending said piece of sheet metal until said side edges are adjacent to form a tubular body with first and second ends defined by said end edges; and joining said adjacent side edges defining a longitudinal seam extending between said first and second ends, characterized in that said step of deep-drawing further comprises the additional step of forming: a corrugated wall in a central region of the piece of sheet metal in which some of said transverse corrugations are formed; two first planar wall portions extending substantially at right angles from opposite sides of said corrugated wall; two second planar wall portions extending substantially at acute angles from said two first planar wall portions; first and second corrugated wall portions in which some of said transverse corrugations are formed, extending substantially at right angles from said second planar wall portions and ending in the side edges; and rounded edges connecting said corrugated wall with said first planar wall portions and also connecting said second planar wall portions with said first and second corrugated wall portions, with the transverse corrugations extending into said rounded edges.