Abstract: A method and apparatus for forming tamper-evident, sealed containers are disclosed. A plurality of filled containers are respectively fitted with generally annular, heat-shrinkable seal members, with the seal members heated by passage through a heat tunnel so that they shrink into conformance with the respective containers. In order to further conform the heat-shrinkable members to the containers, the containers are passed beneath a rotatably driven, resiliently deformable foam roller assembly, which engages each seal member, and urges it downwardly into further conformance with its respective container. In the preferred form, the roller assembly is driven so that its peripheral speed is less than the speed at which the sealed containers are moved therebeneath.

Abstract: A method of making a one-piece container of heat shrinkable thermoplastic foam from sheet stock in which a longitudinally seamed cylindrical sleeve made from such material is placed on a forming mandrel providing the essential shape of the container. An end portion of the sleeve extends cantilever fashion beyond the mandrel. The sleeve is heated to soften it and shrink partially to conformity of the mandrel and shrink to a small elongate tube a fraction of the sleeve's original diameter. The heat softened sleeve is pressed against the bottom end of the mandrel to form a container bottom, and at the same time the other opposite end of the sleeve is upset to form a bead for the container opposite the bottom end.

Abstract: A mandrel for forming a container made of foam plastic sheet material. The mandrel defines the internal configuration of the container and also is used to form a rim on the top edge of the container. The container rim is formed by first expanding the rim in diameter by means of cam actuated segments which extend radially outward from within the confinement of the mandrel structure. Subsequent to the diametrical expansion of the rim, the container, including the exterior of the mandrel, undergoes a translation along the mandrel longitudinal axis, thus causing the container rim to fold back upon itself, thus forming a lid receiving bead.