Patent ID: 9174382
Filing Date: 2015-11-03
Classification: B29C,B32B,Y10T

Abstract:
1. A process for producing a hollow article having a pair of spaced walls, the process comprising: positioning a parison between a first mold half and a second mold half, said first mold half and second mold half together defining a cavity for forming said hollow article, said second mold half having a plurality of displaceable core pins extendable into said cavity, configuring the core pins in a predetermined spaced geometric array, closing said first mold half and second mold half, extending said core pins, thereby pushing localized regions of said parison so as to form corresponding protrusions in said parison, the protrusions defining a corresponding geometric array of structural pillars that join the spaced walls, the spacing density of the structural pillars being determined as a function of desired structural rigidity of the article, expanding an end region of each protrusion through the introduction of air through one or more internal channels provided in each corresponding core pin, the expansion being sufficient to cause an end surface of said protrusion to engage and integrally bond with an opposing inside surface of said parison on complete mold tool closure, introducing a pressurized gas into said parison so as to cause said parison to bear against said cavity to form said hollow article, opening said first and second mold half, allowing said hollow article formed therein to be released.