| 摘要 |
1,091,651. Moulding foamed plastics. SWEDISH CRUCIBLE STEEL CO. Dec. 20, 1965, No. 53888/65. Heading B5A. The annular cavity 83 of a mould 12 is supplied with beads of plastics material, e.g. polystyrene, which are expanded by steam to form an annular foamed plastics article. The mould is supported on a foundation 22 extending into a pit 26, and comprises an outer wall 48, a hollow cylindrical core 82, a base 44, and a cover 14 pivoted at 162 and opened and closed by an hydraulic motor 18. The mould is surrounded by a steam supply manifold 60, a cooling water supply manifold 62 and a manifold 58 which receives condensate from the mould cavity. Perforated walls 70 and 94 are located adjacent the outer wall and the core, and an annular perforated bottom wall 74 is located above an annular vertically reciprocable perforated plate 102. When the beads have been placed in the mould and the cover closed down and secured by a number of circumferentially spaced latching devices 16, steam is passed from the manifold 60 into the mould cavity via ports 54 and the perforated wall 70; steam is also fed to the hollow core from a pipe 206 and passes through ports 84, 86 and 88 and the perforated wall 94 to the mould cavity. Condensate passes through the annular perforated plate 102 and passageways 107 to the condensate manifold and flows to a drain pipe 128 which also receives condensate from the hollow mould core via a port 132. Condensate is also received in a manifold 188 and drained away. After the steam treatment, cold water is fed to the mould cavity via the manifold 62 and ports 56, and also via a manifold 186 and branch pipes connected to ports in the cover 14. Such cooling causes shrinkage of the foamed body which detaches itself from the cavity walls. The cover is then unlatched by operating hydraulic drive units 214 which retract levers 220 from engagement with pins 218, and then opened by the motor 18. The foamed article is then removed from the mould by lifting the annular plate 102 by means of hydraulic motors 20, which raise the plate to the top of the mould cavity. In a modified construction, Fig. 6, not shown, the mould comprises semi-cylindrical halves (250, 252) hinged together and provided with integral semicircular closure plates (282, 284) having filling ports (308) closed by plugs (310). The mould halves are opened by a motor (276), Fig. 4, not shown, and gearing which includes quadrant worm gears (256, 258), Fig. 7, not shown, on hinge bosses (246, 248), whereby the moulded article and the hollow core (324) of the mould can be removed horizontally. The mould core is centred in the mould by a head (402) vertically reciprocable by a motor (396) carried in a base structure (382). |
