| 摘要 |
The mold (6) is opened. Internal wall surfaces (13a, 13b) of both mold halves (7, 8) are coated with unhardened plastic (24a, 24b). This will form the wall of the final molding. At least one joint surface (14a, 14b) of the mold is similarly coated (26). Before hardening, the mold is closed. It is forced together, displacing plastic from the joint, into the molding chamber. It makes a firm material bond with plastic applied to the walls. An Independent claim is included for the mold employed, which has equipment (28) pressing the halves together as described. Preferred features: To make an unfilled, hollow molding, the mold is simply opened following solidification, and the hollow molding is extracted. To make an entirely- or partially filled molding, the hollow molding is filled whilst still in the mold, with a foam or other molding mass, before opening the mold. The mold employed, has one or more filling channels in the walls (lower left). A plug is inserted, long enough to penetrate the wall of the molding to be formed. It is retracted when filling the molding as described. Parting agent is coated onto all surfaces contacting plastic, before the cycle commences. In a variant, the additional plastic (26) may be deposited, before the walls are coated. Mold joining surfaces may be covered-over before coating the walls, a dedicated covering section being used. Only one wall may be coated. A surrounding boundary surface (35) at the edge of the mold join, prevents ejection of plastic during mold closure. Coatings are produced by spraying, injecting-on and/or spreading over the chamber walls and joint surfaces. Coating thicknesses, reflects the desired wall thickness profile of the product. Only two mold sections are employed. |
