GB115466A - Improvements in Girders, Beams, Spars, and the like Rigid Structural Members. - Google Patents

Abstract

115,466. Ford, L. C. May 5, 1917. Framework; planes and the like, construction of.-Girders, beams, spars, ribs, and other rigid structural members are formed from tubes or other hollow bodies by cutting and bending certain portions so that box girders with cross braces or ties are produced. Such girders are applicable for the frames of the wings of aircraft. The girder shown in Fig. 3 is formed by cutting the tube shown in Fig. 1 along the full lines and bending the cut portions along the dotted lines. The cuts 1 for the diagonals 7 on opposite sides are inclined in opposite directions. The flanges 4 of the opposite vertical members 5 may abut or be overlapped and secured together. Bent portions 8 constitute flanges for the booms and may be beaded, ranged, or fluted, or be folded to form tubular booms. Diagonal ties 11, 12 are bent from the top and bottom walls of the tubes. In the modification shown in Fig. 5, the flanges to the parts 5, 7 are omitted and the tube strengthened transversely by strips 14, 14<a> bent from the diagonals 7 and secured to the opposite diagonals 7 and cross braces 11. Two or more tubes may be connected, as shown for example in Fig. 6, by means of the bent portions 5, 7 which may be flat or convex in cross section, and the remaining walls or the tubes may be bent to form a triangular section. In another modification, one tube A<4>, Fig. 9, is secured inside the other tube A' by means of the bent portions a<3>, a<4>, and the top and bottom walls may be similarly connected. The tubular blanks may be rectangular as shown, or circular, triangular, or stream line in section; the shape of the cross section may vary along the length, and the tubes may be twisted or bent longitudinally and be closed at one or both ends. Sheet metal blanks may be cut, stamped, and fluted, and then be formed into tubes or other hollow bodies having the cross braces described above.