GB973559A - Panel assembly with insert fastener - Google Patents

Abstract

973,559. Screw-sockets and bolt-hole bushes; anchoring nuts. F. W. ROHE. Jan. 8, 1963 [Jan. 8, 1962], No. 917/63. Heading F2H. An insert, i.e. a threaded socket, Fig. 6 (not shown), or a bolt hole bush A, is anchored by resin, such as epoxy resin with a curing agent, injected by a nozzle 52, Fig. 5, for setting in a hole 13 (through a sandwich panel, e.g. of an aircraft wall), the insert being introduced between the skin sheets 10, 11 of the panel by a tool D, Fig. 4, so that end pilot portions 28, 31 extending from heads 22, 23 of the insert locate in skin holes 16, 15 and shoulders 29, 32 seat against the skins. A conical surface 34 under the head 23 distends the hole 15 temporarily for the introduction of the head which may, as shown, be larger than the head 22 which can pass through the hole 15 to locate adjacent the smaller hole 16. A head 46 of the tool D, on a shank 45 screwed into a socket of the tool, guides the pilot 28 of the insert A into the hole 16. There is a hole 36 through the head 23 for the injection of the plastic resin and a hole 37 for the venting of air. If the insert heads are of equal diameter, as in Fig. 6 (not shown), the head 23 is introduced first, through the skin 10, a conical portion 32 being used to distend the hole in the skin. A conical portion 26 distends the same hole for the introduction of the trailing head. The insert surface between the heads 22, 23 is knurled or longitudinally ridged. In preparing the hole 13 for the embodiment shown, a drill, Fig. 3 (not shown) makes the hole 15 in the aluminium, alloy or fibre-resin sheet 11 or expands a hole therein made by the drill used to make the smaller hole 16 in the similar sheet 10. The drill then makes the hole 13 in the foamed resin or light metal or honeycomb sheet core and removes the burr from inside the smaller hole 16. The hole 13 need not be centred, in a honeycomb core, in a single cell as shown.