Process for producing plastic containers

Claim 1

IN A METHOD OF MAKING AN OPEN-TOPPED PLASTIC CONTAINER HAVING A LIP CIRCUMSCRIBING THE CONTAINER TOP, A BOTTOM WALL AND SIDE WALLS JOINING SAID LIP TO SAID BOTTOM WALL, THE STEPS OF (1) INJECTION MOLDING IN AN INJECTION MOLD A SUBSTANTIALLY FLAT PARISON HAVING (A) AN OUTER RIM PORTION CORRESPONDING IN SIZE AND CONTOUR TO THE LIP OF THE FINISHED CONTAINER, (B) A CENTRAL PORTION CORRESPONDING SUBSTANTIALLY IN THICKNESS AND CONTOUR TO AT LEAST A PORTION OF SAID CONTAINER BOTTOM WALL, AND (C) A MEDIAL PORTION INTEGRALLY JOINING SAID OUTER RIM TO SAID CENTRAL PORTION AND OF NEITHER THE THICKNESS NOR THE CONTOUR OF THE SIDE WALLS OF SAID CONTAINER, SAID MEDIAL PORTION BEING OF A THICKNESS SUBSTANTIALLY GREATER THAN THE THICKNESS OF SAID CONTAINER SIDE WALLS; (2) RELATIVELY MOVING INTO AXIAL ALIGNMENT (A) SAID PARISON WHILE STILL HOT AND (B) A BLOW MOLD CAVITY HAVING SAID WALL AND BOTTOM WALL PORTIONS CORRESPONDING TO SIZE AND CONTOUR TO THE SIDE WALL AND BOTTOM WALL PORTIONS, RESPECTIVELY, OF THE FINISHED CONTAINER, THE PARISON PROJECTING ACROSS THE BLOW MOLD CAVITY IN A PLANE SUBSTANTIALLY NORMAL TO THE LONGITUDINAL AXIS OF SAID CAVITY AND SAID RIM PORTION STILL BEING AT LEAST PARTIALLY RETAINED IN SAID INJECTION MOLD; (3) MECHANICALLY PUSHING THE CENTRAL PORTION OF SAID PARISON TOWARD THE BOTTOM WALL OF SAID CAVITY, THEREBY (A) POSITIONING SAID CENTRAL PORTION OF SAID PARISON ADJACENT ITS FINAL POSITION IN SAID CAVITY, AND (B) BRINGING SAID MEDIAL PORTION CLOSER IN CONTOUR AND THICKNESS TO THE SIDE WALL PORTIONS OF SAID CONTAINER, WHILE (C) THE OUTER RIM PORTION OF THE PARISON REMAINS AT LEAST PARTIALLY RETAINED IN SAID INJECTION MOLD, THUS (D) DEFORMING THE INITIALLY SUBSTANTIALLY FLAT PARISON TO A BLOWABLE SHAPE; (4) BLOWING THE SO DEFORMED PARISON INTO FULL CONTACT WITH SAID BLOW MOLD CAVITY WITHOUT DISTURBING SAID RIM PORTION IN ITS STILL RETAINED POSITION; AND (5) FINALLY REMOVING THE FINISHED CONTAINER SIDE WALLS AND BOTTOM WALL FROM THE BLOW MOLD AND SAID CONTAINER RIM FROM ITS RETAINED POSITION IN SAID INJECTION MOLD.