Patent ID: 9708456
Date: 2017-07-18
CPC Classifications: B29C,B29D,B29K,C08J,C08L,Y10T

Claim:
1. A method of forming a foamed part, the method comprising: providing a polymer processing system comprising: (i) a screw mounted within a barrel to define a polymer processing space within the barrel; (ii) a polymeric material delivery system in communication with the polymer processing space; (iii) a blowing agent delivery system in communication with the polymer processing space; and (iv) at least one nozzle in fluid communication with a distal portion of the polymer processing space; providing a mold having at least one expandable mold cavity in fluid communication with the nozzle; mixing polymeric material and blowing agent within the polymer processing space to produce an unfoamed mixture; injecting a volume of the mixture of polymeric material and blowing agent through the nozzle and into the expandable mold cavity; and expanding the mold cavity, after injecting the volume of the mixture of polymeric material into the mold cavity, to form the foamed part, wherein expanding the mold cavity comprises an asymmetric lateral displacement of a movable first wall portion of the mold cavity with respect to a stationary second wall portion of the mold cavity, while the volume of the mixture of polymeric material is expanding in the mold cavity, by rotation of the movable first wall portion with respect to the stationary second wall portion.