A device for producing a dyed plastic melt and an undyed plastic melt includes a multi-shaft screw extruder, a first metering installation, a second metering installation, and a control installation for selecting between a first operating mode for producing the dyed plastic melt and a second operating mode for producing the undyed plastic melt. The first metering installation serves for feeding an undyed plastic material through a first infeed opening into a housing of the multi-shaft screw extruder, and the second metering installation serves for feeding at least one color granulate through a second infeed opening into the housing. The plastic material is fed exclusively by way of the first infeed opening such that residual color granulate or dyeing agent contained therein, respectively, which is still located in the second metering installation or in the region of the second infeed opening does not contaminate the undyed plastic melt.

A system and a method for controlling an extrusion line of mixed plastics, wherein a temperature of one or more heaters of the extrusion line is measured by one or more first sensors; a temperature and pressure of an extruder head is measured by one or more pairs of second sensors; a coolant temperature of a set of dies is measured by one or more third sensors; an amperage of an extruder motor is measured by an ammeter; a pulling speed of a pulling unit is measured by a tester; and wherein a computing device configured to receive the measurement data from the one or more first sensors, from the one or more pairs of the second sensors, from the one or more third sensors, from the ammeter, from the tester.

An injection molding machine includes first and second injection units. When it is detected that the first injection unit malfunctions, information that notifies the other injection unit (that is, second injection unit) the fact that the first injection unit is malfunctioning is outputted. The second injection unit that has acquired the malfunction information from the first injection unit carries out a malfunction process based on a preset malfunction process setting corresponding to other-injection-unit malfunction information.

A liquefier assembly for use in an additive manufacturing system to print three-dimensional parts, which includes an upstream pressure-generating stage and downstream flow-regulating stage. The upstream pressure-generating stage includes a drive mechanism, a liquefier configured to melt a consumable material receive from the drive mechanism to produce a molten material in a pressurized state. The downstream flow-regulating stage includes a gear assembly having a casing assembly and a pair of gears disposed within the interior cavity and engaged with each other to regulate a flow of the pressurized molten material through the gear assembly for controlled extrusion.

An assembly for use in an additive manufacturing system to print a three-dimensional part that includes an extruder comprising a gear and a motor that turns the gear, wherein rotation of the gear regulates a flow of material out of the extruder. A controller, provides a control signal to the motor to control the rate at which the motor turns the at least one gear and incorporates a time-varying signal into the control signal to reduce ripples in the material output by the extruder.

A method and system for optimizing a match between the color of an in-line part manufactured by a plastic product production machine and the color of a reference part by adjusting the concentration of masterbatch in the mixture of raw material fed to the plastic product production machine. The optimization of the color is based on spectra of the in-line part and reference part obtained within a short time interval using the same spectrometer, thereby eliminating the requirement for high accuracy spectrometer calibration and allowing the method, which determines the rates at which the base masterbatches are added to the raw material, to be carried out in real time on the manufacturing floor while the plastic product production machine is being operated to manufacture in-line parts.