An injection molding machine includes: a first driving device rotating a screw provided inside a heating cylinder; a second driving device moving the screw forward and backward; a metering control section configured to, by controlling the first driving device and the second driving device, to meter resin while melting the resin, and thereafter rotate the screw in reverse to thereby reduce the pressure of the resin; a first sensor unit for detecting the pressure; a second sensor unit for detecting one or more kinds of physical quantities that affect the change of the pressure; and a prediction section predicting decompressing rotation information based on the pressure detected by the first sensor unit and the one or more kinds of physical quantities detected by the second sensor unit. The metering control section controls the first driving device based on the decompressing rotation information predicted by the prediction section.

An injection molding machine includes: a first driving device rotating a screw provided inside a heating cylinder; a second driving device moving the screw forward and backward; a metering control section configured to, by controlling the first driving device and the second driving device, to meter resin while melting the resin, and thereafter rotate the screw in reverse to thereby reduce the pressure of the resin; a first sensor unit for detecting the pressure; a second sensor unit for detecting one or more kinds of physical quantities that affect the change of the pressure; and a prediction section predicting decompressing rotation information based on the pressure detected by the first sensor unit and the one or more kinds of physical quantities detected by the second sensor unit. The metering control section controls the first driving device based on the decompressing rotation information predicted by the prediction section.

An injection apparatus of the invention injects a molding material supplied from a material supply port, and includes a die, a material supply apparatus that extrudes the molding material that is thread-like or strip-like via the die, and a material guide apparatus that guides the molding material supplied via the die to the material supply port. The material discharge port of the material supply apparatus and the die protrude downward in the material supply apparatus, and a pressure inside the material guide apparatus is reduced by a pressure reducing apparatus from a pressure reducing port provided above the material discharge port of the material supply apparatus and the die.

An injection apparatus of the invention injects a molding material supplied from a material supply port, and includes a die, a material supply apparatus that extrudes the molding material that is thread-like or strip-like via the die, and a material guide apparatus that guides the molding material supplied via the die to the material supply port. The material discharge port of the material supply apparatus and the die protrude downward in the material supply apparatus, and a pressure inside the material guide apparatus is reduced by a pressure reducing apparatus from a pressure reducing port provided above the material discharge port of the material supply apparatus and the die.

A control device for an injection molding machine including a cylinder into which a resin is supplied and a screw that moves forward and rearward and rotates inside the cylinder, includes a metering control unit that performs metering of the resin inside the cylinder by controlling forward rotation and rearward movement of the screw until the screw has been moved rearward to a predetermined metering position, based on predetermined metering conditions, a rearward movement speed acquisition unit acquiring a rearward movement speed of the screw, a speed determination unit that determines a suck back speed for causing a resin pressure to reach a target pressure, based on the rearward movement speed acquired during metering by the rearward movement speed acquisition unit, and a suck back control unit causing the screw to move further rearward based on the suck back speed, after the screw has reached the predetermined metering position.

A control device for an injection molding machine including a cylinder into which a resin is supplied and a screw that moves forward and rearward and rotates inside the cylinder, includes a metering control unit that performs metering of the resin inside the cylinder by controlling forward rotation and rearward movement of the screw until the screw has been moved rearward to a predetermined metering position, based on predetermined metering conditions, a rearward movement speed acquisition unit acquiring a rearward movement speed of the screw, a speed determination unit that determines a suck back speed for causing a resin pressure to reach a target pressure, based on the rearward movement speed acquired during metering by the rearward movement speed acquisition unit, and a suck back control unit causing the screw to move further rearward based on the suck back speed, after the screw has reached the predetermined metering position.

An injection molding machine for foam molding includes: a heating cylinder; a screw disposed in the heating cylinder; and a plurality of inlet portions provided in the heating cylinder and configured to introduce inert gas. An inside of the heating cylinder includes a starvation section on an upstream side in which a pressure of the resin is decreased, and the inert gas from the plurality of inlet portions being to be supplied in the starvation section. Each of the plurality of inlet portions is provided with a check valve or an opening and closing mechanism. A product P×N of an interval P of the plurality of inlet portions and a number N of the inlet portions is 0.5H or more and 1.71H or less with respect to a length H of the starvation section.

An injection molding machine for foam molding includes: a heating cylinder; a screw disposed in the heating cylinder; and a plurality of inlet portions provided in the heating cylinder and configured to introduce inert gas. An inside of the heating cylinder includes a starvation section on an upstream side in which a pressure of the resin is decreased, and the inert gas from the plurality of inlet portions being to be supplied in the starvation section. Each of the plurality of inlet portions is provided with a check valve or an opening and closing mechanism. A product P×N of an interval P of the plurality of inlet portions and a number N of the inlet portions is 0.5H or more and 1.71H or less with respect to a length H of the starvation section.

To provide a plasticizing device capable of easily executing maintenance of a barrel. A plasticizing device includes: a drive motor; a flat screw having a groove forming surface in which a groove is formed, and rotating around a rotation axis of the drive motor; a barrel having a facing surface facing the groove forming surface and having a communication hole formed therein; and a heating unit configured to heat a material supplied between the flat screw and the barrel. The barrel has a separate structure including, when viewed from a direction orthogonal to the rotation axis, a first barrel having the facing surface, and a second barrel separated from the facing surface.

To provide a plasticizing device capable of easily executing maintenance of a barrel. A plasticizing device includes: a drive motor; a flat screw having a groove forming surface in which a groove is formed, and rotating around a rotation axis of the drive motor; a barrel having a facing surface facing the groove forming surface and having a communication hole formed therein; and a heating unit configured to heat a material supplied between the flat screw and the barrel. The barrel has a separate structure including, when viewed from a direction orthogonal to the rotation axis, a first barrel having the facing surface, and a second barrel separated from the facing surface.