Patent GB-1477827-A (GB)
Title: Method and apparatus for the manufacture of reinforced concrete  modular building units
IPC: B28B7/28
Filed: 1974-07-17
Abstract: 1477827 Mould for concrete modular building unit DUFFERIN STEEL Ltd 17 July 1974 [3 May 1973] 21004/73 Heading B5A The floor and four walls of an accommodation module are moulded from reinforced concrete on a removable pallet positioned in a mould cavity defined by retractible mould walls, floor and core, the core and two of the mould walls being retractible vertically. The mould floor 28 (Fig. 3) comprises tubular supports 31, 40 mounted on I-beams 44 within a pit 45, and is movable vertically by motor driven screw jacks and nuts 47, 49. Motion is guided by dollies 50 having rollers 52 running on rails 48. When raised for moulding, the floor 28 seals against a pallet frame 22 rolling on tracks 25. The mould core comprises an internally reinforced box 36 mounted on beams 102, 100 that travel on vertical towers 104, movement being effected by screws (106) (Fig. 10, not reproduced) in the towers 104 and motor driven nuts (108) mounted on beams 100. The core bottom supports sub-cores that define apertures in the moulded module. The end walls (33), (35) (in plane of paper of Fig. 3) run horizontally on rollers 90 (Fig. 8) on I-beams 88 supported on the core beams 100 (Fig. 3). When in the moulding position (Fig. 8) defining a mould cavity 38, the top of each wall (33), 35 is pressed against a core flange 74a by tie rods 92 and nuts 93. The wall bottoms seal against the pallet 23 and are attached to the floor beams 44 by pins 99, devises 98 and screws 95. Projections on the walls (not shown) define window and door openings in the moulded module. The side walls 34, 32 (Fig. 3) are moved horizontally on rollers engaging the ground 46 and upper rails 62, by double-acting rams (61) (see Fig. 6, not reproduced). The top of the walls 32, 34 are pressed against a core flange 74 (Fig. 7) by tie rods 70 engaging lugs 85 on the walls. The wall bottoms seal against the pallet 22 and are locked by lugs 68a on rotatable tie rods 68 engaging the pallet 22 and floor beams 40 and tightened by nuts 64. The walls support projections 36a. Locks.-The core 36 and floor 28 (Fig. 3) are locked together in a first embodiment (Fig. 12) by jaws 112 that engage projections 120 on the core beams 102, and the dollies 50 of the floor. The jaws 112 are moved together and apart by a double-acting ram 118 operating links 116 pivoted to parallel jaw arms 111. The arms 111 are slidingly supported by the side walls 32, 34. In a second embodiment (Fig. 14), bolts 140 and nuts 141 mounted on the floor beams 40 are operated by a wrench 152 passing through a tube 149 within the core 36. Operation.-Steel reinforcing rod or wire mesh, conduits, window frames &c. are mounted on the pallet 22 (Fig. 3), which is wheeled into a moulding position while the floor, core and four walls are retracted. The floor, core and walls are moved to their moulding positions and locked to one another, and concrete pumped and vibrated into the moulding cavity adjacent the base of one wall, until it seeps through bleed holes (or past) the core flanges 74, 74a (Figs. 7, 8). Alternatively, the back pressure of the concrete pump is monitored. After 1 hour, the building containing the moulding apparatus is sealed and used as an autoclave, by raising the temperature with steam to 160‹ F. at 40‹ F./hour. Finally, the mould is dismantled and the module removed on the pallet 22.