A method and system for adjusting melt pressure in an injection molding material that allows calculating a melt pressure of a molten plastic material to be injected and based on the calculated melt pressure and a desired melt pressure adjusting operation of an injection molding machine. This control of an injection molding cycle using the method and system of plastic melt pressure determination allows production of parts of increased quality and consistency.

In a method for operating an injection moulding machine in the absence of a backflow barrier, plastic melt is injected by a plasticising device into a cavity in a screw antechamber of a plasticising screw adapted to rotate about a longitudinal axis and to move translationally by a drive unit during an injection phase and a holding-pressure phase. A rotational drive of the drive unit is controlled such that a speed of the plasticising screw causes overlay of a backflow of the plastic melt from the screw antechamber back into screw threads of the plasticising screw by an opposing delivery flow as a result of a rotation of the plasticising screw due to a translational injection movement of the plasticising screw. A differential flow is established from the backflow and the opposing delivery flow and influenced at least during the injection phase by influencing the speed of the plasticising screw.

An additive injection system for use in injection molding machines to inject additive materials, such as fluids or powders, downstream of a nozzle of the injection molding machine. The additive injection unit has an additive tank to store or contain additive material and additive injectors that inject an additive material into an injection molding machine. A pump pumps the additive material from the tank through a common manifold connected to the additive injectors to be injected into the injection molding machine. A controller controls operation of the additive injection device and one or more sensors coupled to the additive injection device can provide feedback to the controller.

An injection molding apparatus including an injection device, a mold, a gas supply device, and a temperature control device is provided. The mold has a mold cavity, wherein the injection device is adapted to inject a material into the mold cavity. The gas supply device is adapted to supply a gas to the mold cavity such that the pressure in the mold cavity is increased. The temperature control device is adapted to control the temperature in the mold cavity. In addition, an injection molding method is also provided.

An injection molded article of the present invention comprises: a first color resin part with one end having a first thickness, and the other end having a wedge shaped core layer of which the thickness becomes thinner; and a second color resin part with one end having a second thickness, and the other end having a surface layer surrounding the core layer, wherein the upper surface and the lower surface of the surface layer surrounding the core layer has a gradation due to the core layer thereinside. According to the injection molded article having color gradation, it is possible to adjust the size and location of a color gradation section, and it is easy to adjust the thickness.

A device for assisting molding condition determination includes a molding state data adjustment amount obtaining unit and a molding condition element adjustment amount obtaining unit. The molding state data adjustment amount obtaining unit obtains, using a first learning model, a molding state data adjustment amount having a value equivalent to a difference between molding state data detected by a sensor and a molding state data target value. The molding condition element adjustment amount obtaining unit obtains, using a second learning model, an adjustment amount for a molding condition element corresponding to the molding state data adjustment amount.

A pressure controller for an injection molding machine capable of reducing variations of pressure in a mold in molding cycles and providing molded articles of stable quality is provided. The pressure controller includes an in-mold pressure estimation unit for estimating a pressure in the mold based on an injection pressure detected with an injection pressure detection unit, and an amount of movement of a screw detected with a screw movement amount detection unit, and an in-mold pressure control unit for controlling such that the estimated in-mold pressure becomes a set in-mold pressure after the pressure control is performed in a dwell step with an injection pressure control unit.

In order to improve the consistency of molded products as viscosity shifts throughout a run, a controller of an injection molding machine executes a calibration cycle in accordance with a mold cycle. The controller analyzes a plurality of sensed melt pressure values during the calibration cycle to determine one or more calibration metrics. The controller then uses the calibration metrics when executing each mold cycle of the run. More particularly, during each mold cycle of the run, the controller detects a plurality of sensed melt pressures prior to and during a fill phase of the mold cycle and compares the plurality of sensed melt pressures to the one or more calibration metrics to predict cavity pressure for a pack and hold phase of the mold cycle. The controller then adjusts a set point pressure for the pack and hold phase based on the predicted cavity pressure.

A control device includes: an injection control unit that controls, in a pressure holding process of controlling a pressure acting on a molding material from an injection member, an injection drive source based on a set value of the pressure and an actual value of the pressure. The injection control unit performs pressure reduction control to gradually reduce the actual value of the pressure with respect to the set value of the pressure from a middle of a k-th stage (k is an integer of 1 or more and n or less). The control device includes a ratio setting unit that sets a time ratio Tr(k) in the k-th stage and a pressure ratio ?Pr(k) in the k-th stage based on a set value P(k) of the pressure in the k-th stage, a set value T(k) of a holding time in the k-th stage, and information stored in advance.

A method and apparatus for injection molding of plastic material into a cavity of a mold by means of at least one injector whose opening and closing occurs through an electronic control unit and wherein an undesired opening of the mold caused by any overpressure of the plastic material injected into the cavity of the mold is detected by means of transducers and corrected by means of the electronic control unit. The transducers are arranged outside the cavity of the mold.