摘要 |
A sword blade is formed of a rib (3) connected by stress concentration studs (19) to a pair of extension strips (2), so that the moment of inertia of the cross section of the rib, with respect to a plane of inertia (x'-x) passing through the concentration studs, is equal that of the strips, all along the length of the sword. The concentration studs concentrate stress in the blade and are deformed and break, thus alerting the user to discard the sword, end faces (10b, 14a) of the rib and extension strips are formed parallel to the plane of inertia, for distribution stress across these faces, to prevent the starting of cracks causing the sword to break.
|