GB248051A - Improvements in aircraft framework - Google Patents

Abstract

248,051. Larrard, J. H. Nov. 21, 1924. Framework; planes, construction of.-An aerofoil rib or other framework structure is composed of detachable booms and web members'which are braced together when in position, by tensioning one or more flexible wires, cables. or strips, which extend continuously and diagonally between the booms. In the construction shown in Figs. 1 and 2, the booms 1 and web members 2 are of channel section. The members 2, which are sufficientty narrow to enter the channel of the booms, are formed at their ends with notches 5 adapted to fit on rivets 3 furnished at intervals along the edges of the booms and inside the channel. Flexible wires 6 are threaded along the channels of the web mmbers 2, passed over the rivets 3, and tensioned by turnbuckle-s 7 to brace the whole and form a rigid structure. According to the modification shown in Fig. 5, the web members 2 are arranged vertically end two diagonal tensioning wires 6 are used crossing one another in the bays. The rivets are surrounded by sleeves 4, and both the rivets and sleeves are provided with diametrical holes 8 through which the tensioning wires are passed. The rivets have square heads so that they may be turned to adjust the tension of the wires 6, and they may be prevented from unwinding by burring over their ends, if desired, into key slots 9. Instead of using rivets the booms may be formed with turned-in tongues or pressed out projections. The wire, or other device, when tensioned, may be caused to operate a detent which locks the rib to a spar, such as 10, Fig. 1.