method and device for the manufacture of shaped kunststofvoorwerpen

摘要

1431071 Sheet-forming G T J EGGEN 28 March 1973 [6 April 1972] 14962/73 Heading B5A A heated, deformable plastic mass is attached to a supporting surface sealed around the circumference of a mould and a forming fluid is introduced between the supporting surface and the periphery of the layer to press the layer away from the supporting surface initially at the periphery of the layer and conform it to the mould. As shown in Fig. 1, the apparatus comprises a mould 1 and a support 2 having a backing plate 9 defining a cavity 3. Mould 1 has an annular gutter 4 and is connected to support 2 by flexible annular connection 5. Plate 9 has a cooling means 8 and is vertically movable on guide rods 6. A plastic mass 7 is applied to support 2 by fusing or electrostatically depositing pulverulent material, e.g. polythene, and the apparatus closed so that the edge of mass 7 is cooled by means 8. As plate 9 and support 2 are raised, mass 7 remains adhered thereto except for its edge portion which adheres to the mould 1. Air is supplied above mass 7 and suction applied therebelow via duct (11, Fig. 3, not shown) so that mass 7 is shaped against mould 1. In Figs. 5-8 (not shown), plate 9 and support 2 are flat. In Fig. 12, the base of mould 1 is formed by plunger 12 having a flexible rim 13. Mould 1 also has cavities 14 for heating and cooling fluid. Plastic mass 7 may comprise several layers and may be peripherally held against mould 1 by a clamping ring.