INJECTION MOLDING METHOD AND INJECTION MOLDING MACHINE

• Main Authors: ITO TATSURO, KAWASHIMA TAIICHIRO
• Format: Patent
• Language: English
• Published: 18.10.2007
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; 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

PROBLEM TO BE SOLVED: To provide an injection molding method which prevents the occurrence of a bad phenomenon such as gas burning or the like of a resin molded product and molds a resin molded product excellent in appearance and surface precision, and and also to provide an injection molding machine. SOLUTION: The mold 2 of the injection molding machine 1 is constituted of: a cavity 20 in which the resin raw material 80 is charged; and the gas passing port 41 opened to the back side molding surface 202 of the cavity 20. When the gas passing port 41 is connected to a vacuum means 61, the residual gas G1 in the cavity 20 is sucked from the gas passing port 41 to evacuate the cavity 20. On the other hand, when the gas passing port 41 is connected to a pressure increase means 62, a pressing gas G2 is introduced into the gap between the back side molding surface 202 of the cavity 20 and the resin raw material 80 in the cavity 20 from the gas passing port 41 and the resin raw material 80 is pressed to the surface side molding surface 201 of the cavity 20. COPYRIGHT: (C)2008,JPO&INPIT