Patent ID: 7568369
Filing Date: 2009-08-04
Classification: B21D,B65D,Y10S

Abstract:
1. A molding unit for shaping a container preform into a shaped container having a predetermined sidewall contour, the preform being supported on a tool which moves the preform into and out of the molding unit and supports the preform in the molding unit during a shaping process, the molding unit comprising: a two-part mold split vertically in half providing two mold sections with inner surfaces of the respective mold sections shaped to produce a specific container contour matching the shape of the inner surfaces; a pressurization unit positioned over an open end of the preform prior to closing the mold, a pressurized fluid being introduced into the preform through the pressurization unit after the mold is closed to force a sidewall of the preform outwardly against the inner surfaces of the mold sections to shape the preform to the specific container contour, a height of the preform contracting as a sidewall expands, the preform having a main body portion and a top piece attached thereto by a double seam, the pressurization unit including: each mold section inner surface structured to provide space between each mold section and the top double seam such that the top double seam is not contacted by the mold sections or the nose of the pressurization unit head so to be unsupported by the mold and free to move during the shaping process, and the container preform having a lower end seated on the tool with the downward force imparted by the pressurization unit head on the preform preventing the lower end from lifting off the tool so that the height contraction of the preform occurs only from the upper end of the preform.