VACUUM MOLD FOR MAKING FOAMED POLYMERIC ARTICLES

• Main Author: RICHARD H. IMMEL
• Format: Patent
• Language: English
• Published: 28.11.1972
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ARTCOLLECTIONS [XRACs] AND DIGESTS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

A mold for the vacuum molding of foamed cellular thermoplastic articles has two cooperating sections which when placed together define a mold cavity. Each section has three shells and two standard chests including an inner shell, an intermediate shell and an outer shell. The intermediate shell is spaced apart from the inner shell to define a first chest and the outer shell is spaced apart from the intermediate shell to define a second chest. The first chest has inlet and outlet means which are connected to a source of heating and cooling media and the second chest has inlet and outlet means which are connected to atmospheric air, compressed air and vacuum lines. A plurality of venting means communicate between the mold cavity and the second chest whereby a vacuum may be drawn or air may be charged into the mold cavity. At least one section has inlet means for passing expanded or partially expanded granules of a thermoplastic material into the mold cavity after the sections are brought together and a means for opening and closing the mold sections by moving one of the sections relative to the other.