Patent ID: 7628877

Claim:
A method for manufacturing a structure having a first surface and a second surface opposite the first surface, the method comprising: forming the structure such that the structure comprises: a first section, wherein the structure is solid between the first surface and the second surface in the first section; and a second section, wherein the second section has a space between the first surface and the second surface, wherein, in the second section, the first surface is part of a first wall having a first interior surface facing the space and the second surface is part of a second wall having a second interior surface facing the space, and wherein in the second section an interface surface faces the space, the interface surface being adjacent the first section; and placing a foam in the second section such that the foam occupies the space, wherein the foam is bonded to the first interior surface, the second interior surface, and the interface surface; wherein the structure is further formed such that the interface surface has a bullnose shape, wherein the bullnose shape has an upper portion nearer the second surface and a lower portion nearer the first surface, wherein the upper portion has a first rate of curvature and the lower portion has a second rate of curvature, and wherein the first rate of curvature is higher than the second rate of curvature.