摘要 |
A unitary composite frame member of two or more structural elements. A first and a second of the elements each contributes strength to the member. The second element, a plastic, encloses the first element on essentially all surfaces along the length of the first element, and is molded to itself through recesses of openings in an edge of the first element. The first element is discontinuous in that it is two walls attached lengthwise, and a third wall parallel to them and separate from them. In one embodiment, the third wall and one of the two walls intersect laterally.
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