Mold construction for a process and apparatus for manufacturing shaped containers

Abstract

A molding unit () for use in a can shaping process. Container preforms (F) are mounted on a table () which is rotated so a blank is moved from an initial loading station (P) to a molding station (P). The molding unit includes a two-part mold () split vertically in half, and an inner surface () of each mold half is shaped to produce a desired can profile. Once the preform is in place, a pressurization unit () is lowered into place from above the mold onto an open, upper end of the preform. The mold is then closed and pressurized air is introduced into the preform and forces the sidewall of the preform outwardly against the inner surface of the mold to conform the preform into a desired container profile. The height of the preform tries to contract as its sidewall expands, but a force imparted to the preform by the pressurization unit controls the direction of any contraction so to prevent distortion of the container. After the shaping operation is complete, the pressurized air is withdrawn from the container, the mold is opened, and the pressurization unit is removed. The table is rotated to an off-loading station (P) where the shaped container is removed from the table and conveyed to the next operating location. As the table moves the contoured container to the off-loading station, another container preform is loaded into the mold.