Method and device for controlling the shrink behavior of plastic materials during primary shaping

A process for the manufacture of a plastic shell, the process comprising the steps of:

• introducing liquified plastic between an inner mold and an outer mold in order for the liquified plastic to cure therein;
• controlling the shrinkage behavior during curing to provide an original shaping of the plastic by fixing the plastic on said outer mold at plural fixation locations to form plural inner cavities with each inner cavity being between said inner mold and said plastic in a region of one of said plural fixation locations and to form plural outer cavities with each outer cavity being between said outer mold and said plastic in a region between adjacent fixation locations with said inner and outer cavities alternating with each said inner cavity being between outer cavities and each outer cavity being between inner cavities.

A device for controlling the shrinkage behavior during the original shaping of plastics for a process including introducing liquified plastic between an inner mold and an outer mold in order for the liquified plastic to cure therein, wherein the plastic is partially fixed on said outer mold during the curing, the device comprising;

• a casting mold accommodating at least the outer mold and the inner mold inserted into said casting mold, wherein said liquified plastic to be molded can be introduced between said mold parts;
• and
• means for fixing said liquid plastic on said outer mold during curing and resulting shrinkage of the plastic to form inner cavities with each inner cavity being between said inner mold and said plastic in a region of one of said plural fixation locations and to form outer cavities with each outer cavity being between said outer mold and said plastic in a region between plural fixation locations.