Injection-molding method and apparatus

摘要

An injection-molding method for covering a front face and a rear face of a plate-shaped member 116 with a molded layer 118 by injection-molding, the injection-molding method comprising: a step of preparing a first die 141 having a front side cavity face 150 that will face the front face 131 of the plate-shaped member 116 and a first gate 152 opening at this front side cavity face 150 and a first pressure sensor 153 fronted on the front side cavity face 150 and preparing a second die 143 having a rear side cavity face 165 that will face the rear face 133 of the plate-shaped member 116 and a second gate 167 opening at the rear side cavity face 165 and a second pressure sensor 168 fronted on the rear side cavity face 165; a step of sandwiching the plate-shaped member 116 with the first die 141 and the second die 143 and thereby forming a front side cavity 151 with the front side cavity face 150 of the first die 141 and the front face 131 of the plate-shaped member 116 and forming rear side cavity 166 with the rear side cavity face 165 of the second die 143 and the rear face 133 of the plate-shaped member 116; a step of injecting a molding material such as resin through the first gate 152 into the front side cavity 151 and injecting a molding material through the second gate 167 into the rear side cavity 166; and a step of stopping the injection of molding material into the front side cavity 151 when a measured value of the first pressure sensor 153 reaches a prescribed value and stopping the injection of molding material into the rear side cavity 166 when a measured value of the second pressure sensor 168 reaches a prescribed value, to mold front and rear side molded layers 132, 134 respectively in the front and rear side cavities 151, 166.