Method and apparatus for reforming a container bottom

Abstract

A reforming apparatus, and method of using the same, is provided for reforming the bottom of a container to increase the dome reversal pressure and improve the drop resistance of a beverage container. The invention is particularly apt for use in reforming a beverage container integrally formed from a thin metallic sheet. Such containers generally have an open top portion connected to an outer wall that is disposed about a container axis. The outer wall is connected to a bottom portion having an annular support surface, an outer surface for connecting the annular support surface and the outer wall, a recessed or dome surface, and an inner surface for connecting the annular support surface and the dome surface. The invention provides a container rotating device for spinning, supporting, and positioning a container during reformation. A container positioning assembly is included to accurately position the container relative to reforming tools (e.g., rollers). The container positioning assembly includes an assembly for applying a resilient compressive force on the bottom portion of the container to maintain the container in an axially centered position within the reforming apparatus. The invention further comprises inner and/or outer rollers, disposed for outward and inward movement, respectively, for engaging and reforming the inner surface and/or outer surface of the bottom portion of a container body. In one embodiment, a single inner roller is disposed for reforming an inner surface while two outer rollers supportably engage an outer surface in opposing relation to the inner roller (e.g., the inner roller is positioned on a radius that is located between the radii on which the outer rollers are positioned).