An injection molding machine is provided that includes a clamping force sensor that detects a clamping force of a mold, and a clamping force monitoring unit that monitors a detected value of the clamping force sensor and calculates a first mold open distance and/or a second mold open distance. The first mold open distance is calculated based on the difference between the maximum value of the detected values obtained during an injection process and a pressure holding process and the detected value obtained at the start of the injection process. The second mold open distance that is calculated based on the difference between the detected value obtained at the end of the pressure holding process and the detected value obtained at the start of the injection process.

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 method for operating an injection-molding machine, including the steps: a) in a current injection-molding cycle, after an accepted-part reference injection-molding cycle learned in a learning phase: detecting a compound pressure change k.sub.1 relative to an accepted-part reference compound pressure p.sub.masse, ref during at least part of an injection phase of the current injection-molding cycle by measuring a current compound pressure p.sub.masse, act and comparing the current compound pressure p with the accepted-part reference compound pressure p.sub.masse, ref, b) determining a target mold internal pressure curve p.sub.wkz,soll (1) for a holding-pressure phase of the current injection-molding cycle, wherein for this purpose a mold internal pressure curve p.sub.wkz,ref (t) of the accepted-part reference injection-molding cycle is adjusted at least in dependence on the compound pressure change k.sub.1 detected in step a), and c) traveling the holding-pressure curve p.sub.masse, Hld, act (t) of the current injection-molding cycle in such a way that an actual mold internal pressure curve pwkz,act (0 of the current injection-molding cycle runs at least more closely along the target mold internal pressure curve p.sub.wkz,soll (t) than a mold internal pressure curve p.sub.wkz,ref(t) that is unchanged in comparison with the accepted-part reference cycle.

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.

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.

The injection moulding of articles formed by plastic materials having different characteristics, for example of different colours, is carried out in a single injection cycle in which the first and the second plastic materials are injected into a first and into a second zone of a mould cavity by first and second injectors controlled according to specific modes so as to define a shape and/or a position of a weld line.

The injection moulding of articles formed by plastic materials having different characteristics, for example of different colours, is carried out in a single injection cycle in which the first and the second plastic materials are injected into a first and into a second zone of a mould cavity by first and second injectors controlled according to specific modes so as to define a shape and/or a position of a weld line.

The injection moulding of articles formed by plastic materials having different characteristics, for example of different colours, is carried out in a single injection cycle in which the first and the second plastic materials are injected into a first and into a second zone of a mould cavity by first and second injectors controlled according to specific modes so as to define a shape and/or a position of a weld line.

A method is provided for controlling an injection molding system, which includes a mold having an inner surface defining at least two groups of cavities, each group of cavities defining precisely one cavity with one pressure sensor at the inner surface. Each group of cavities is at least partially surrounded by a tempering unit that provides an energy flow to the surrounded cavities. According to the method, a pressure is determined in each group of cavities of the at least two groups of cavities. A reference pressure is determined for each group of cavities. A difference between the reference pressure and the pressure in at least one group of cavities is determined and controlled to become minimum by manipulating the energy flow of the tempering unit.

An Injection molding apparatus injection molding apparatus (10a) comprising: one or more first downstream channels (166, 166a, 166b) and associated first gates (34, 34a, 34b) that deliver injection fluid (18) to a first cavity (300a) of a mold system (302, 303) and to one or more second downstream channels (168, 168a, 168b) and associated second gates (32, 32a, 32b) that deliver injection fluid to a second cavity (300b) of the mold system (302, 303), the mold system being clamped together under a selected force, the apparatus including a first upstream valve (118) that enables and disables flow of the injection fluid to the first gates (34, 34a, 34b) and a second upstream valve (108) that enables and disables flow of the injection fluid to the one or more second gates (32, 32a, 32b), the apparatus including a control system (20) adapted to open or enable flow of the injection fluid (18) to the one or more first gates (34, 34a, 34b) at a first selected time and to further instruct the second upstream valve (108) to open or enable flow of the injection fluid (18) to the one or more second gates (32, 32a, 32b) at a second selected time that is delayed relative to the first selected time during the course of an injection cycle.