INJECTION MOLDING METHOD AND INJECTION MOLD

摘要

PROBLEM TO BE SOLVED: To provide an injection molding method preventing the 'turn-over' of the joining parts of a pair of half hollow bodies molded by primary molding even if the joining parts are thin when the joining parts of a pair of the half hollow bodies are joined by secondary molding. SOLUTION: A slide mold (10) and a fixed mold (1) are used in primary molding to mold a pair of the half hollow molded articles (A and B) so as to provide the joining parts (As and Bs) to the peripheral edges of the half hollow molded articles (A and B) and the slide mold (10) is slid with respect to the fixed mold (1) in secondary molding to abut the joining parts (As and Bs) of a pair of the half hollow molded articles (A and B). A molten resin for secondary molding is injected in the joining space part (SK) of the abutted thin-walled joining parts through a side gate (15) to join a pair of the half hollow molded articles to obtain a hollow molded article. At this time, a property is imparted to the flow of the molten resin injected from the side gate (15) so as to turn the flow of the molten resin toward the joining part (As) near to the thin-walled joining parts of the joining parts constituting the joining space part (SK) to allow the molten resin to flow in the joining space part (SK).