Pactiv Corporation

Mobil Oil Corporation

Philip Stanley Baker

Kenneth James Simmons

John Gardner Fuller

Stephen L Goulette

Jonathan Gross

Daniel Lawrence Donk

Steven Robert Hogarth

Roland De May

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 multilayer structure designed to overcome the shortcomings of previously known thermoformed sheet structures. Articles may be formed by a method of the present invention having an attractive outer appearance associated with polyolefin films containing inert inorganic fillers while having the advantageous processing properties of oriented films. The present invention is directed to multilayer structures, methods for forming the multilayer structures as well as shaped articles formed from the multilayer structures. The multilayer structure has at least a first sheet layer comprising a polyolefin and preferably an inert organic filler, and a film layer which advantageously comprises an oriented polyolefin or polyester. The present invention may comprise one or more of each of the above described sheet and film layers.

Multilayered polyolefin structure

An arrangement for the thermoforming of molded plastic articles from a continuous web of a thermoplastic material, and more particularly, a trim in place thermoforming arrangement in which the plastic articles are simultaneously molded and at least substantially or completely separated from the remaining thermoplastic web material. A high degree of alignment and precision is obtained between cooperating cutting blades employed in the trimming of the thermoformed articles, because of a unique self-aligning or floating support structure of at least one of the cutting blades operating in conjunction with the thermoforming apparatus. The self-aligning action provided for between the slidingly contacting cutting blades allows for an automatic compensation for any temperature changes and blade wear encountered during operation, and with only one movable part being required for the trim in place device.

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Fairport, NY, United States of America

Philip Stanley Baker