Patent ID: 6264455
Filing Date: 2001-07-24
Classification: B29C

Abstract:
An apparatus for producing plastic objects with solid regions and hollow regions, comprising:a molding tool including at least two halves with a cavity;a plasticizing unit;a plastic injection nozzle;at least one fluid injection nozzle; andmeans for essentially blocking off a part of the cavity;the apparatus:blocking off a portion of the cavity of a molding tool;injecting plastic melt into the unblocked portion of the cavity of the molding tool along a melt flow path, which extends from the plasticizing unit through the plastic injection nozzle into the molding tool;unblocking the cavity enabling the plastic melt to reach the previously blocked-off portion of the cavity;simultaneously and/or subsequently to injecting the plastic melt, injecting a pressurized fluid into the melt via the at least one fluid injection nozzle, so that the melt injected into the molding tool is distributed into the desired portions of the cavity while forming a hollow space and is pressed against the cavity walls of the molding tool;allowing the molded part thus produced to cool down to a temperature below the melting point of the plastic melt;relieving the cavity of the pressure of the compressed fluid; anddemolding the molded part.