Injection molding method of box-shaped product

Abstract

Abstract PURPOSE:To prevent the occurrence of a sink mark in a molding by a method in which when molten resin in molds is being hardened by cooling, compressed air is sent into the through holes of a porous part by an air controller to press the corner portions of the molding. CONSTITUTION:When molten resin in molds 3 is being hardened by cooling, compressed air is sent into the through holes 5 of a porous part 6 by an air controller and blown onto the corners 1C of a molding 1 in such a way as to form an air trap 9 until the molten resin is hardened. The inside of the corners 1C of the molding is pressed outwards by the air trap 9 to prevent the occurrence of sink mark in the molding 1.

Inventors

• 👤 Hidetomo Suzuki
• 👤 鈴木　秀知

Bibliographic Details