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 unit includes an injection cylinder and a plasticizing screw in the injection cylinder. The plasticizing screw is rotatable about a longitudinal axis for plasticizing plastic raw material and is movable linearly along the longitudinal axis for injecting molten plastic raw material. The injection cylinder has an infeed and plasticizing zone for the plastic raw material with a circular-cylindrical inner wall with a constant diameter along the longitudinal axis, a metering zone in front of the infeed and plasticizing zone along the longitudinal axis in the injection direction with a circular-cylindrical inner wall with a constant diameter along the longitudinal axis, and a nozzle head in front of the metering zone in the injection direction with a nozzle-shaped inner wall. The diameter of the circular-cylindrical inner wall of the metering zone is smaller than the diameter of the circular-cylindrical inner wall of the infeed and plasticizing zone.

A control device for an injection molding machine is equipped with a pressure acquisition unit that acquires a pressure of a resin, a reverse rotation control unit that causes a screw to be rotated in reverse, after the screw has reached a predetermined metering position, a measurement unit that measures an elapsed time or a rotation amount of the screw from when the screw has reached the predetermined metering position, and a rearward movement control unit that initiates sucking back of the screw in an overlapping manner with the reverse rotation of the screw, in the case that a predetermined rearward movement initiation time has elapsed, or in the case that the screw has been rotated by a predetermined rearward movement initiation rotation amount, from when the screw has reached the predetermined metering position.

Plasticizing unit for a moulding machine having at least one plasticizing screw for plasticizing a plasticizable material and injecting it into at least one mould cavity, which at least one plasticizing screw is rotationally and axially movable in relation to a screw axis, wherein at least one filter is provided, which is arranged downstream of the at least one plasticizing screw in a direction of flow of a mass flow of the plasticizable material.

A method of determining a solution state of a gas in a plastic melt used in a plastic shaping method includes: (vi) providing the plastic melt together with the gas in a chamber, (vii) altering—in particular reducing—a volume of the chamber to alter a pressure of the plastic melt together with the gas—in particular increased from a first pressure value to a second pressure value, (viii) introducing the plastic melt into a shaping cavity, (ix) computing at least one compression parameter characteristic of the compression behaviour of the plastic melt, in particular a modulus of compression, from the first pressure value and the second pressure value, and (x) determining from the at least one compression parameter whether the gas is substantially completely dissolved in the plastic melt and/or a solubility limit of the gas in the plastic melt is determined from the at least one compression parameter.

The present disclosure prevents load from being produced in an injection molding machine. The control device for an injection molding machine according to one embodiment of the present disclosure has a determining part that is configured to determine, based on information detected in accordance with a movement of a measurement motor provided in the injection molding machine, whether or not an operation of removing or attaching a screw that rotates in accordance with the measurement motor has been performed.

When an injection molding machine performs molding, the mold clamping force on the mold is adjusted on the basis of a mold displacement of the mold or the injection peak pressure and injection foremost position so that the molding is performed without causing flash and by an appropriate mold clamping force with which energy can be reduced. The amount of mold displacement and also the injection peak pressure and the injection foremost position are monitored during automatic operation. If there occurs no mold displacement change exceeding a threshold or if there occurs no injection peak pressure anomaly or injection foremost position anomaly exceeding thresholds, the automatic operation is continued. If the mold displacement change occurs or if the injection peak pressure anomaly and the injection foremost position anomaly occur, the operation of the injection molding machine is stopped.

Provided is an injection molding method for resin that contains reinforcing fiber, the method being capable of easily eliminating uneven distribution of added components. The injection molding method is provided with: a plasticizing step for supplying resin pellets P and added components to a cylinder equipped with a screw 10, which has a rotating axis as the center is capable of rotating normally and in reverse, and generating molten resin by rotating the screw 10 in the normal direction; and an injecting step for injecting the molten resin M comprising the added components into a cavity. In the plasticizing step, a reverse rotation operation for reversing the rotation of the screw 10 is performed or a screw-stopping operation of stopping the normal rotation of the screw 10 is performed with a prescribed timing and for a prescribed period.

A plasticizing device includes a plasticizing mechanism including a feeding port for receiving a material and configured to plasticize the material to generate a melted material and a material feeding mechanism configured to feed the material to the plasticizing mechanism. The material feeding mechanism includes a housing including a depositing port communicating with the feeding port, the housing storing the material, and a rotating member housed in the housing and capable of rotating along an inner edge of the housing. A plurality of through-holes are provided in the rotating member at intervals along an outer circumference of the rotating member. When the rotating member rotates and any one of the plurality of through-holes and the depositing port communicate, the material stored in the housing is fed from the feeding port to the plasticizing mechanism through the depositing port.

The present invention offers a technique for providing assistance in setting at least one of the temperature of a nozzle and the temperature of a cylinder. A control device for an injection molding machine includes a monitoring part configured to monitor, during a filling step of filling the inside of a mold device with a molding material, a change in the filling pressure acting on the molding material.