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 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 method of performing an injection cycle having a duration comprising: beginning the injection cycle with the valve pins associated with two or more nozzles in a gate closed position, selecting a first one of the two or more nozzles and controllably driving its associated valve pin from the gate closed position to a selected first axial upstream position, upon downstream flow of the injection fluid through a cavity the preselected distance, controllably driving the valve pin associated with the other of the two or more nozzles to a selected second axial position upstream, holding or controllably driving the valve pin associated with the first one of the two or more nozzles in or to one or more reduced flow axial upstream positions that are partially closed.

A method of performing an injection cycle having a duration comprising: beginning the injection cycle with the valve pins associated with two or more nozzles in a gate closed position, selecting a first one of the two or more nozzles and controllably driving its associated valve pin from the gate closed position to a selected first axial upstream position, upon downstream flow of the injection fluid through a cavity the preselected distance, controllably driving the valve pin associated with the other of the two or more nozzles to a selected second axial position upstream, holding or controllably driving the valve pin associated with the first one of the two or more nozzles in or to one or more reduced flow axial upstream positions that are partially closed.

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.

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.

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.

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.

Provided is a method for manufacturing a fiber reinforced resin molded article capable of effectively suppressing formation of a weld line, and such a manufacturing device thereof. Even with multiple gates (resin inlets), resin is poured from a second gate (second resin inlet) when resin flow is detected at the second gate (second resin inlet), and then the resin poured from a first gate (first resin inlet) and the resin poured from the second gate (second resin inlet) are made smoothly meet.

Provided is a method for manufacturing a fiber reinforced resin molded article capable of effectively suppressing formation of a weld line, and such a manufacturing device thereof. Even with multiple gates (resin inlets), resin is poured from a second gate (second resin inlet) when resin flow is detected at the second gate (second resin inlet), and then the resin poured from a first gate (first resin inlet) and the resin poured from the second gate (second resin inlet) are made smoothly meet.