Method for fabricating thermoplastic containers

摘要

A cup or other nestable container is formed from two continuous web stocks of thermoplastic material, particularly an expanded thermoplastic material. A rectangular blank to form the sidewall of the container is severed from a first web stock, and formed into a cylindrical sleeve with the end portions thereof joined to one another in a liquid-tight seam extending the full height thereof. A circular bottom closure disc is cut from a second web stock and transferred to a recessed top of a forming mandrel carried on a continuously-moving turret. The cylindrical sleeve is positioned about the forming mandrel, which carries the sleeve and bottom closure disc to various subassemblies that cooperate with the forming mandrel to produce a finished cup. The cylindrical sleeve is forced downwardly into a heated rimming die positioned adjacent the lower edge of the forming mandrel to cause the lower edge of the sleeve to be rimmed. The cylindrical sleeve is shrunken to conform to the side contour of the forming mandrel, and the upper end of the sleeve extends inwardly to provide an inturned position overlying the periphery of the bottom closure disc. The bottom closure disc and inturned portion are sealingly joined and contoured to finish the bottom of the container.