Improvements relating to the reinforcement or substantially plane structures

摘要

838,434. Metal sheeting. BRITISH THOMSON-HOUSTON CO. Ltd. Jan. 28, 1957 [Jan. 27, 1956], No. 2751/56. Class 20(2) [Also in Group XL(c)] A metal sheet for the reflector of a radar beam aerial is stiffened by having stuck to one side of the sheet, hubs 1 arranged at the apices of equilateral triangles and joined to one another by ribs 3 which are stuck in slots in the hubs. The hubs are sections of a slotted extruded aluminium alloy rod. Ribs of the same material are of rectangular section with the major dimension at right angles to the plane of the sheet. Holes 5 receive screws by which the sheet may be attached to a supporting framework.