| 摘要 |
PURPOSE:To lessen unevenenness of properties without being affected by uneven injection conditions by carrying out gate cut when the mold opening volume becomes the given set value at the time when resin is injected into a cavity. CONSTITUTION:The mold opening volume of a mold increases gradually after starting injection of molten resin into a cavity 10. Said mold opening volume is measured continuously by a position sensor 21, and its signal output is amplified by an amplifier 22 and transmitted to a computing element 23. The computing element 22 compares and computes said mold opening signal and said set value signal from a setting device 24, and when the mold opening volume conforms with the set value, a drive signal of a gate cut cylinder 9 is transmitted to a selector valve 25. A valve 252 is moved in the left direction by said arrangement to transfer pressurized oil from a hydraulic pressure device 26 to the gate cut cylinder 9 through an oil circuit 262, a gate cut punch 8 is projected to the side of a fixed mold 2 for carrying out gate cut, punch a central section of a molded product and form a center hole. |
