Vehicle bumper beam having non-uniform cross sections

摘要

A bumper for a vehicle comprises a hollow tubular beam, and has two side rail mounting portions and a front impact portion disposed between and formed continuously with the side rail mounting portions. The front impact portion includes an initial impact region and two additional deforming regions, with the initial impact region being disposed between the additional deforming regions. The initial impact region has top and bottom surfaces that are generally flat and the additional deforming regions each have top and bottom surfaces that are generally convex.