VERFAHREN UND VORRICHTUNG ZUR BEARBEITUNG VON VORFORMLINGEN

摘要

Preforms(1) are injection molded and after demolding from the tool are subjected to vacuum to press at least some areas of the molding wall(4) against a cooling surface(15). Vacuum is applied to the outside or inside of a preform with the latter positioned inside a cavity(14) in a porous cooling insert(3) supported in a frame(2). Channels(10) supply the vacuum to the porous material. Cooling(11) channels are also incorporated in the insert which has a covering seal(13). The insert may comprise local separate inserts. Local inserts are connected via control valves to vacuum sources and a compressed gas source to form air cushions. Vacuum can be supplied to the inside of a preform via a porous mandrel, areas of which may be covered by seals. Inner mandrels may have a distribution chamber covered by a membrane. Preform deformation forms an intermediate step in either a single or two stage injection blow molding process. An independent claim is made for the process equipment which includes a porous insert for cooling all or specific areas of thermoplastic preforms.