Abstract: Systems and approaches for controlling an injection molding machine and a mold forming a mold cavity and being controlled according to an injection cycle. The systems and methods include analyzing a model of at least one of the injection molding machine, the mold, and a molten material to determine initial values for one or more control parameters of the injection molding machine, and executing a run of injection cycles at the injection molding machine; measuring operation of the injection molding machine during a particular injection cycle of the run of injection cycles; determining one or more operational parameters exceed a threshold; and upon determining that the one or more operational parameters exceed the threshold, adjusting the one or more control parameters for subsequent injection cycles of the run of injection cycles.

Abstract: A controller for an injection molding system is in communication with a melt flow control unit, a gas assist control unit, and a gas counter pressure control unit. The controller can effect real-time adjustments to gas assist pressure and/or gas counter pressure as a function of melt pressure or flow front position.

Abstract: A method of detecting and compensating for a non-operational mold cavity in an injection molding apparatus having a plurality of mold cavities and an injection molding screw or ram includes injecting, via the injection molding screw or ram, a molten thermoplastic material into the plurality of mold cavities. The method includes measuring a first process parameter of the injection molding apparatus at a pre-determined time during or after the injecting. The method also includes determining, based on the first process parameter, whether one or more mold cavities of the plurality of mold cavities are non-operational. Then, when it is determined that one or more mold cavities are non-operational, the method includes automatically adjusting the first process parameter or a second process parameter of the injection molding apparatus.

Abstract: A method and system for co-injection molding of two molten plastic materials that allows monitoring and utilization of injection pressure and optionally melt pressure and/or flow front pressure during an injection run. A controller alters the injection pressure so as to achieve and maintain optimal or desired ratios of injection pressure, and optionally melt pressure and/or flow front pressure, of the two molten plastic materials. This allows for more precise part manufacture, including reducing the thickness of a skin or shell layer compared to a core layer of a molded part.

Abstract: Systems and approaches for determining design of experiment parameters using largest empty area rectangle optimization for an injection molding system. The systems and methods include obtaining pressure versus time data sets indicative of fill step pressures and corresponding fill step times for a plurality of mold cycles and defining a low and high pressure versus time curves from the data sets, with the low and high pressure versus time curves being two surfaces of a geometric shape. The systems and methods further include identifying a top surface and a bottom surface of the geometric shape; identifying a rectangle having the largest area of all rectangles contained within the first geometric shape; and generating design of experiment parameters from the largest area rectangle.

Abstract: Systems and approaches for controlling an injection molding machine and a mold forming a mold cavity and being controlled according to an injection cycle. The systems and methods include analyzing a model of at least one of the injection molding machine, the mold, and a molten material to determine initial values for one or more control parameters of the injection molding machine, and executing a run of injection cycles at the injection molding machine; measuring operation of the injection molding machine during a particular injection cycle of the run of injection cycles; determining one or more operational parameters exceed a threshold; and upon determining that the one or more operational parameters exceed the threshold, adjusting the one or more control parameters for subsequent injection cycles of the run of injection cycles.

Abstract: Non-time dependent calculated variables based on measured strain are used to effectively determine an optimal hold profile for an expanding crosslinking polymer part in a mold cavity. A system and/or approach may first inject molten expanding crosslinking polymer into a mold cavity, then measure strain at the mold cavity or at another location within the injection molding system, and then calculate at least one non-time dependent variable during an injection molding cycle. Next, the system and/or method commences a hold profile for the part, and upon completing the hold profile, the part is ejected from the mold cavity, whereupon a cure profile is commenced.

Abstract: A system includes a cavity, an injection nozzle configured to inject material into the cavity, and a plurality of sensors at sensor locations. Each of the plurality of sensors is configured to measure parameters at one of the sensor locations. The system lacks a strain gauge. The system further includes a controller configured to control a flow rate of the injection of material into the cavity. The controller is configured to receive the measured parameters and compare the received information to predetermined curves. The controller is configured to control the flow rate when the measured parameters deviate from the predetermined curves.

Abstract: A method of monitoring and controlling a molding clamping apparatus in an injection molding or other molding process is disclosed. The method includes creating a target strain profile, receiving a deviation limit, receiving a change in strain relating to a mold while it is closing from a first strain gauge, identifying a deviation from a target strain profile based on the output from the first strain gauge, determining that the deviation exceeds the deviation limit, and adjusting the rate or force of clamp movement. The target strain profile may have a first portion relating to a clamp closing process, a second portion relating to a filling process, and a third portion relating to a clamp opening process. The first portion relating to the clamp closing process may include an intermediate portion relating to a coining process having an intermediate clamp force setpoint.

Abstract: Embodiments within the scope of the present disclosure are directed to external sensor kits that may be included in new injection molds or retrofitted into existing injection molds in order to approximate conditions within a mold, such as pressure or the location of a melt flow front. Such kits are designed to amplify meaningful measurements obtained by the external sensor kit so that noise measurements do not prevent the approximation of conditions within a mold. In some embodiments within the scope of the present disclosure, an external sensor kit includes a strain gauge sensor, a coupon, a support bracket, and a hammer. The strain gauge sensor is placed on a surface of the coupon and measures the strain in the coupon.

Abstract: Systems and approaches for controlling an injection molding machine having a first configuration and a mold forming a mold cavity and being controlled according to an injection cycle include obtaining a pattern for a portion of an injection cycle of an injection molding machine having a second configuration and operating the injection molding machine having the first configuration to inject a molten material into the mold cavity. While operating the injection molding machine having the first configuration, the obtained pattern is used to control a portion of the injection cycle.

Abstract: Systems and approaches for controlling an injection molding machine having a mold forming a mold cavity and being controlled according to an injection cycle include obtaining a pattern for the injection cycle, operating the injection molding machine to inject a molten material into the mold cavity, and measuring a cavity pressure value of the mold cavity during the mold cycle. Upon measuring a nominal cavity pressure value, a pattern recognition portion of the injection cycle that is at least partially dependent on the obtained pattern commences where a driving force being exerted on the molten material is adjusted such that the measured cavity pressure matches the obtained pattern for the injection cycle.

Abstract: A method of determining melt flow front travel in a molding apparatus includes setting a sensor threshold, receiving a sensor amount as an output from a sensor monitoring a nozzle of the molding apparatus, and determining that the sensor amount exceeds the sensor threshold. The method further includes receiving a screw location, calculating a travel distance of the screw from the screw location, and calculating melt flow front travel based on the travel distance of the screw. The method further includes receiving, via an interface, an operator generated value for the desired melt flow front travel to be reached, and sending, via an interface, an analog or digital output after the operator generated value has been reached. A method of detecting a leaking condition of a check valve is also included.

Abstract: In order to reduce oscillations in process variables of an injection molding process, an injection molding machine may be operatively connected to a model database that stores models of injection molding machines and molds. A tuning controller may set initial gain values of a variable-gain proportional-integral-derivative (PID) controller. To set the initial gains, the tuning controller may be configured to obtain, from the model database, a model for a first and second injection molding machines and a model for a mold. The tuning controller may analyze the models to determine a correlation between injection molding machine parameters and mold cycle performance for the mold. Accordingly, the tuning controller may apply the correlation to determine an initial gain value for a least one of the first, second, and third gains of the PID controller. The tuning controller may then set the initial gain values for the PID controller.

Abstract: 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.

Abstract: 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.

Abstract: Systems and approaches for controlling an injection molding machine having a mold forming a mold cavity and being controlled according to an injection cycle include extruding a molten polymer according to an extrusion profile and measuring at least one variable during the extrusion profile with a first sensor. At least one extrusion operational parameter is adjusted based on the measured variable. The extrusion profile is terminated upon the molten polymer exceeding a first threshold, and the molten polymer is injected into the mold cavity according to an injection profile via a screw that moves from a first position to a second position. Upon completion of the injection profile, a recovery profile commences in which the screw is moved to the first position.

Abstract: In order to reduce oscillations in process variables of an injection molding process, a variable-gain proportional-integral-derivative (PID) controller is utilized to control one or more of the process variables. The injection molding system may also include a tuning controller to automatically tune at least one of the proportional, integral, or derivative gains within a mold cycle. The tuning controller may obtain sensor data that monitors the operation of the injection molding machine to determine an adjustment to at least one of the proportional, integral, or derivative gains. The tuning controller may adjust the gains of the variable-gain PID controller in accordance with the determined adjustment to the at least one of the proportional, integral, or derivative gains.

Abstract: Systems and approaches for controlling an injection molding machine and a mold forming a mold cavity and being controlled according to an injection cycle. The systems and methods include analyzing a model of at least one of the injection molding machine, the mold, and a molten material to determine initial values for one or more control parameters of the injection molding machine, and executing a run of injection cycles at the injection molding machine; measuring operation of the injection molding machine during a particular injection cycle of the run of injection cycles; determining one or more operational parameters exceed a threshold; and upon determining that the one or more operational parameters exceed the threshold, adjusting the one or more control parameters for subsequent injection cycles of the run of injection cycles.