Improvements in core shuttering suitable for moulding hollow walls

摘要

616,697. Casting concrete; cores. RUMBLE, R. W. June 8, 1945, Nos. 14529 and 14530. Convention dates, June 8, 1944, and April 7, 1945. [Class 20(ii)] Collapsable core shuttering for casting hollow walls comprises a body portion 2 formed from parallel plates 5a, 5b and edge portions formed from flexible spring U- shaped members 24, the limbs 26 of which frictionally engage the outer faces of the plates 5a, 5b. The plates 5a, 5b are reinforced by staggered, interengaging corrugated sheets 8, and vertical edge portions 10 of box section. The body is closed at top and bottom by angle-members, the horizontal flanges 11a, 11b of which are bent back on themselves to form freely interengaging tongues and grooves. The angle-members project above the body at the top and are spaced slightly inside the body at the bottom to form a spigot and socket to enable a number of bodies to be joined lengthwise. The plates 5a, 5b are moved apart to expand and allowed to approach each other to collapse, the core, by the vertical movement of bars 16, having a number of cut-away tapered portions engaging bolts 19 in the edge portions 10 of the plates. The bars 16 of successive body portions are connected together. The limbs 26 of the edge portions 24 are forced apart as the body portion 2 is expanded and spring towards each other as the bars 16 are raised to allow the core to collapse. In a modification, the edge portions 24 are secured to the body and are drawn inwards towards the body portion as the bars 16 are raised by lugs 39 or the bars 16 having inclined surfaces 48 to engage projecting lugs 38 on the edge portions 24. When the core is expanded, the edge portions are projected outwards by inclined spring strips 43 which engage the lugs 38 but yield if the edge portions engage an obstruction. After collapsing the core further upward, pull on the bars 16 will remove it from the moulded cavity, the bolts 19 engaging ledges 21 on the bars 16. The edge members may be coterminous with the body portions 2 or may extend over several body portions, as shown. A continuous cavity may be moulded by closing the gaps between adjacent cores with thin metal sheets, and a single core may be increased in width by adding additional edge portions, the limbs of each of which clasp the preceding edge portion between them. Specification 616,527, which describes the tie bars 51 which may be used to hold cores in position inside wall shuttering 49, is referred to.