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.

An injection molding apparatus includes a plasticizing portion, a measurement injection portion that is disposed between the plasticizing portion and a molding mold, measures the plasticized material, and injects the measured plasticized material into the molding mold, a first drive portion changing a relative position between the plasticizing portion and the measurement injection portion, a pressure detection portion detecting a pressure inside the measurement injection portion and a control portion, in which the measurement injection portion is configured such that a volume of an internal space thereof, in which the plasticized material is stored, changes according to a change in the relative position between the measurement injection portion and the plasticizing portion, and the control portion executes at least one of a measurement operation of causing the measurement injection portion to measure the plasticized material by controlling the first drive portion to move the plasticizing portion and the measurement injection portion in a direction away from each other, and an injection operation of injecting the measured plasticized material into the molding mold by controlling the first drive portion to move the plasticizing portion and the measurement injection portion in a direction approaching each other depending on the pressure.

A material delivery device includes: a plasticization unit having a screw and configured to plasticize a material by rotation of the screw to produce a plasticized material; a flow path through which the plasticized material flows; a nozzle having a nozzle opening that communicates with the flow path and delivers the plasticized material to an outside; a cylinder coupled to the flow path; a rod inserted into the cylinder; and a first pressure detection unit configured to detect a pressure of the plasticized material in the flow path via the rod. In a longitudinal direction of the rod, the rod has a rod end surface facing the flow path and a transmission unit at an opposite side of the rod end surface, and transmits a force due to the pressure received at the rod end surface to the first pressure detection unit via the transmission unit.

In one aspect, a method of molding a multilayer article comprises causing a surface layer material injection unit to commence injecting a surface layer material into a mold cavity via a surface layer material channel. Then, an internal layer material injection unit commences injecting an internal layer material into the mold cavity an internal layer material channel. Then, during application of a hold pressure upon the surface layer material in the surface layer material channel and with the surface and internal layer material injection units in fluid communication with one another, a pullback stroke is effected at the internal layer material injection unit. After a delay interval, at least one physical parameter indicative of a post-pullback pressure of the internal layer material is detected, and an indicator of pullback effectiveness is generated based on the post-pullback pressure indicated by the at least one physical parameter relative to a threshold pressure.

A plasticizing device includes: a material storage unit having a charging port and configured to store pellet-shaped resin pellets; a plasticizing unit having a supply port in communication with the charging port and configured to plasticize at least a part of the resin pellets to generate a shaping material; a coupling pipe having a coupling path coupling the charging port and the supply port; a first material sensor configured to detect a remaining quantity of the resin pellets in the coupling path; and a control unit. The material storage unit includes a material supply mechanism configured to supply the resin pellets to the coupling path, and when the remaining quantity of the resin pellets detected by the first material sensor is less than a first reference value, the control unit controls the material supply mechanism to supply a predetermined quantity of the resin pellets to the coupling path.

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.

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.

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.

A method of determining a target value of a state variable includes preparing a mixture of the molding material and the gas with different test values of the state variable, and the mixture is respectively compressed or decompressed. In the compression or decompression step, the state variable of the mixture and/or a further state variable of the mixture is measured directly or indirectly, and determination values of a compression behavior variable characteristic of the compression behavior of the mixture are determined from the measurement values. A criterion directed to a solution state of the gas is checked, and a lowest or highest value of the state variable is deduced at which the gas is in solution in the molding material. The lowest or highest value of the state variable at which the gas is in solution in the molding material is used as the target value.

A temperature sensor used in a molding machine is provided. The temperature sensor comprises a cylindrical fiber probe through which an optical fiber is inserted; an outer housing having a shaft, into which the fiber probe is inserted to be displaceable in an axial direction; a protective window disposed on a tip end side of the fiber probe and configured to protect a tip end of the fiber probe; and an elastic member that presses the fiber probe toward the protective window.