Pactiv Corporation

Tenneco Packaging Inc.

Kenneth James Simmons

Philip Stanley Baker

John Gardner Fuller

Donald E Rowe

Phillip S Baker

Steven Robert Hogarth

Richard A Cummings

A pair of form keys and a method for forming reverse drafts in foam parts are disclosed. A male form key is reciprocally mounted in a first mold half in a retracted position. A female form key is rotatably mounted in a second mold half in a neutral position. The first mold half includes a first drive pin that when engaged, moves the male form key into engagement with a foam sheet to form an undercut as the first and second mold halves are closed. The first mold half also includes a second drive pin that engages the female form key as the first and second mold halves close rotating the female form key into engagement with the foam sheet and the male form key. After closure of the mold and the product is formed, the mold is opened. As this occurs, the drive pins are disengaged and the male form key retracts and the female form key rotates to their neutral positions. The formed product may then be stripped from the mold while maintaining the reverse draft or undercut. In a further embodiment the male form key and the female form key are fluid actuated.

Method of forming a thermoformed foam part

Mold with fluid driven form keys

A pair of form keys and a method for forming reverse drafts in foam parts are disclosed. A male form key is reciprocally mounted in a first mold half in a retracted position. A female form key is rotatably mounted in a second mold half in a neutral position. The first mold half includes a first drive pin that when engaged, moves the male form key into engagement with a foam sheet to form an undercut as the first and second mold halves are closed. The first mold half also includes a second drive pin that engages the female form key as the first and second mold halves close rotating the female form key into engagement with the foam sheet and the male form key. After closure of the mold and the product is formed, the mold is opened. As this occurs, the drive pins are disengaged and the male form key retracts and the female form key rotates to their neutral positions. The formed product may then be stripped from the mold while maintaining the reverse draft or undercut.

Form keys and method for thermoforming undercuts in foam parts

A disposable food container comprises a lid and a base optionally connected to each other along a resilient hinge. The lid includes a top wall, a continuous lid side wall, and a plurality of lid corners. The lid side wall encompasses the top wall and extends downwardly and outwardly from the top wall. The plurality of lid corners are at least partially formed by the lid side wall and include a pair of front lid corners. The base includes a bottom wall, a continuous base side wall, and a plurality of base corners. The base side wall encompasses the bottom wall and extends upwardly and outwardly from the bottom wall. The plurality of base corners are at least partially formed by the base side wall and include a pair of front base corners. If the container is provided with a resilient hinge, the pair of front lid corners and the pair of front base corners are spaced away from the hinge. The container includes a corner latch closure for releasably engaging the lid and the base in a closed position. The corner latch closure includes at least a pair of slots and at least a pair of slot engaging structures that can be interlocked with each other. The pair of slots are formed by the respective front base corners, while the pair of slot engaging structures are formed by the respective front lid corners.

Container with a corner latch closure

Growing community of inventors

Stanley, NY, United States of America

Kenneth James Simmons