A method for the preparation, which is integrally formed, a three-dimensional shaped bodies

摘要

The plastic is formed (folded by bending the blank) in free space, avoiding use of straight edges and folding dies. The required forces (slight) are introduced through non-heated areas. Independent claims are also included for: (1) Formation of e.g. a plastic display pocket. It is made of homogeneous or modified polymethyl methacrylate. (2) Production equipment comprising blank-holding and bending equipment. Preferred features: Formation is by folding along lines. During holding for formation, the section is heated along lines for folding, with wide heating zones for expansion and impressing. To make projections, a plunger is used locally, within a heating zone. Temperature and/or width of the heating region, varies along the line of forming, for desired formation of the fold edges, as a function of the material substance and thickness. Nearby, intentional cooling takes place. By heating along a curve, the product is given a (three-dimensionally) curved surface. During folding, hot molding takes place, with mechanical upsetting, forming reinforcement ridges along the forming lines. U- or OMICRON folds are produced by material expansion on the lines of formation. The surface is given a textured or profiled surface on one or both sides. Recesses, optionally in a pattern, are formed as a result of heating and deformation. Before heating and reforming, the material is embossed or engraved and/or blank assemblies are arranged upon it. Material thickness is preferably about 6.5. mm. Preferred equipment includes a heating unit covered by similar or differing heating elements (104). Cylinder (108) units with suction cups (110) are used for bending and holding the material (106). They are mounted to rotate on end trunnions.