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.

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 machine is provided with a nozzle touch mechanism configured to press a nozzle attached to an injection device against a mold, a drive unit configured to move the injection device, a drive compression member connected to the drive unit, an injection compression member connected to the injection device, at least one resilient member interposed preloaded between the drive compression member and the injection compression member, and at least one strain sensor mounted on the drive compression member.

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.

A monitoring apparatus for molds includes a control unit connectable to a first and second sensor associable with the mold and configured for emitting respective signals representative of a deformation parameter and temperature parameter of the mold. The control unit, in order to define an alert condition, is configured for: defining a value of a threshold parameter as a function of the temperature of the mold and comparing such value of the deformation parameter with a value of a threshold parameter defined as a function of the temperature of the mold; or normalizing, at a reference temperature, the value of the deformation parameter determined at the temperature of the mold and comparing a value of a threshold parameter, defined at the reference temperature, with the value of the normalized deformation parameter at the same reference temperature. Also forming the object of the present invention is a monitoring method and a data medium.

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.

The molding machine includes a cylinder, a screw built in the cylinder, and a state detection device. The state detection device includes a sensor for detecting a state of the screw. The state detection device is attached to the screw outside the cylinder.

Non-time dependent measured variables 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 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.

A shrinkage detection device for a polymer injection molding apparatus detects a shrinkage experienced by an injection molded element for assessing a quality of the molded element. Shrinkage, along with temperature and pressure of the melt within the mold during cooling, indicates a sufficiency of the resulting molded element for intended purposes. Sufficiency includes parameters such as flexibility, shear strength and longevity, and is accurately performed can replace conventional sample testing of molded articles that are expensive and time consuming.

Non-time dependent measured variables 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 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.