| 摘要 |
In the process, after the injection moulding of blowing-agent-containing plastic melt from a screw plasticator (1) via a three-way valve (4) into the mould cavity (23) of an injection mould (2) and after the solidification of a compact outer layer along the mould wall, a predetermined quantity of melt is displaced out of the moulding interior via the three-way valve into a vessel (40). To this end, a hollow needle (30) is driven into the moulding interior and, via a feed valve (34), gas is blown into the moulding interior, the pressure of which gas exceeds that of the blowing agent. After the displacement, the feed valve (34) is closed and an outlet valve (36) is opened. The hollow needle (30) is withdrawn and the moulding ejected. In the next cycle, a piston (41) forces the melt out of the vessel (40) back into the injection mould (2). The sequences of functions are controlled by a control device (5). By the process, dimensionally stiff but lightweight requisites with complicated shapes, for example flat pallets or furniture, can be produced without core in one work operation, even if they consist of a plurality of hollow bodies and solid-foam elements connecting said hollow bodies. <IMAGE>
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