公开(公告)号：US09914247B2

公开(公告)日：2018-03-13

申请号：US14381927

申请日：2013-02-28

Applicant: Dart Container Corporation

Inventor： Krishna Nadella

IPC: B29C44/20 ,  B29C44/34 ,  C08J9/33 ,  C08J9/12 ,  B29C44/58 ,  B29K101/12 ,  B29K105/00 ,  B29L7/00

CPC classification number: B29C44/20 ,  B29C44/3403 ,  B29C44/3442 ,  B29C44/3453 ,  B29C44/587 ,  B29K2101/12 ,  B29K2105/256 ,  B29K2913/00 ,  B29K2995/0065 ,  B29L2007/00 ,  C08J9/122 ,  C08J9/33 ,  C08J2201/032 ,  C08J2203/06 ,  C08J2367/02

Abstract: A method for infusing gas into a thermoplastic material includes positioning a sheet of a thermoplastic material into a vertical or substantially vertical position; positioning a sheet of a gas-permeable material into a vertical or substantially vertical position; and winding together the positioned sheet of thermoplastic material sheet and the positioned sheet of gas-permeable material to form a roll of the thermoplastic material interleaved with the gas-permeable material, the interleaved roll having a longitudinal axis oriented in a vertical or substantially vertical position. The method also includes exposing the interleaved roll to an atmosphere of a gas pressurized to infuse the thermoplastic material with the gas, while the longitudinal axis of the interleaved roll is oriented in a vertical or substantially vertical position; and then unwinding the gas-infused interleaved roll, while the longitudinal axis of the interleaved roll remains in a vertical or substantially vertical position.

公开(公告)号：US09884440B2

公开(公告)日：2018-02-06

申请号：US15243243

申请日：2016-08-22

Applicant: DART CONTAINER CORPORATION

Inventor： Gregory Branch ,  Krishna Nadella

IPC: B29C44/34 ,  B29C44/20 ,  B29C51/08 ,  B29K67/00 ,  B29K105/04

CPC classification number: B29C44/3453 ,  B29C44/20 ,  B29C44/3446 ,  B29C51/082 ,  B29K2067/00 ,  B29K2067/003 ,  B29K2105/04 ,  B29K2105/041

Abstract: Disclosed herein are roll fed air heated flotation ovens and related thermoforming systems, assemblies, and machines that enable the corrugation-free expansion of a gas impregnated thermoplastic web passing through an oven chamber (without use of a pin-chain assembly), as well as to related methods. In an embodiment, a gas impregnated thermoplastic web is conveyed and expanded through an elongated air heated oven chamber, wherein the elongated oven chamber includes a plurality of downwardly directed heated air nozzles positioned at regular intervals along and within the upper portion of the oven chamber, and a plurality of upwardly directed heated air nozzles positioned at regular intervals along and within the lower portion of the oven chamber, but staggered apart from the downwardly directed heated air nozzles such that the gas impregnated thermoplastic material web undulates in an up and down wavelike fashion, thereby minimizing sagging, bagging, puckering, and/or buckling of the web.