GB546686A - Improvements in or relating to panel members for use in the construction of hollow bodies - Google Patents

Abstract

546,686. Compound sheet materials, panels, moulding, plywood. KING, E. P. Aug. 16, 1940, No. 24605/39. [Class 87 (ii)] [Also in Groups VIII and XXIII] In a panel member built up of layers of fibrous material impregnated with a thermosetting or thermo-plastic composition in which the outer layer or layers are continuous over the surface of the panel, separately formed spaced ribs, corrugations or the like are attached to one of the layers and a continuous reinforcing layer overlies or interconnects the layer and the ribs or the like. As shown in Fig. 1, layers of flat or slightly curved veneer 11, impregnated with phenol-formaldehyde resin are assembled with ribs 12 of similar veneer laid edgewise. Both surfaces are covered with layers 13, 14 of impregnated textile material and the whole is consolidated in a hydraulic press. In Fig. 2 the ribs are replaced by corrugated veneer 17 and in moulding the assembly, temporary iron filling strips 19 are placed in the hollow of the corrugations. The bars 19 may be made in two complementary wedge-shaped sections to facilitate withdrawal, or they may be of fusible metal which is melted out after moulding. The form shown in Fig. 3 is made by laying steel filling pieces 21 wrapped with impregnated fabric 22 in sheets of impregnated veneer 23 and impregnated fabric 24. Veneer strips 25 are inserted between the wrapped bars and the assembly is covered with impregnated veneer 26 and fabric 27. Layers 24, 27 may be omitted. The panel shown in Fig. 4 comprises outer layers of impregnated fabric 28, 29 between which is disposed fabric 33 laid alternately over and under temporary filling bars 32. Cellular structures may be made by moulding upon the ribs of Fig. 1 or the corrugations of Fig. 2 either flat or slightly curved panels. The products may be used in making wings and fuselages of aircraft.