PRODUCTION OF FOAM PACKED BLOW MOLDED PRODUCT

• Main Author: YAMANE YASUO
• Format: Patent
• Language: English
• Published: 09.10.1995
• Edition: 6
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULARARTICLES; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

PURPOSE:To stabilize the supply of a foam packed blow molded product, to facilitate process control, to reduce equipment cost and to shorten a manufacturing time by injecting a molten resin mixed with compressed air into the parison present in a cavity under high pressure and opening the interior of the parison to atmospheric pressure. CONSTITUTION:A parison P is injected in a cavity la to be hermetically sealed therein by mold clamping and a foaming material injection nozzle 6 and air nozzles 7, 8 are allowed to protrude into the cavity 1a to be allowed to pierce the parison. A molten resin 10 mixed with compressed air is injected into the parison P held to a high temp. state from the foaming material injection nozzle 6 and, at the same time, compressed air is separately injected into the parison P from the air nozzles 7, 8 to keep the pressure in the parison P high. Thereafter, the interior of the parison 12 is opened to the atmosphere through the air nozzles 7, 8. By this constitution, the air bubbles contained in the resin 10 expand to fill the parison P with the resin. The parison P filled with the resin 10 is cooled and solidified as it is to obtain a product 11.