A hot runner injection molding apparatus, and method of use, is disclosed in which strain gauges are provided in the temperature zones of the hot runner injection molding apparatus and a hot runner controller creates a target strain profile, detects deviations from the target strain profile in any temperature zone based on the strain readings provided by the strain gauges in each temperature zone, and instructs correction of deviations from the target strain profile in any deviating temperature zone by adjusting the heat produced by a heater or heaters in the deviating temperature zone. The target strain profile may be based on a median or average of strain readings provided over time by the strain gauges in each temperature zone. A hollow installation tube for placing the strain gauges in the hot runner injection molding apparatus is also disclosed.

A strain gauge nozzle adapter that may be placed between a barrel end cap and a nozzle body of an injection molding system, the strain gauge nozzle adapter having a strain gauge pin that measures strain within the strain gauge nozzle adapter for use in approximating conditions within an injection molding system, such as pressure or the location of a melt flow front. The strain gauge nozzle adapter may include a plurality of strain gauge pins. An alternative material insert in the strain gauge nozzle adapter may surround a strain gauge pin to amplify meaningful measurements obtained by the strain gauge pin so that noise measurements do not compromise the accuracy of approximation of conditions within a mold.

Methods of monitoring and controlling a molding process using a sensed change in strain provided by a strain gauge are provided. A target strain profile is created for a molding process of a molding apparatus. An upper and lower deviation limit from the target strain profile for the molding process is provided. If a sensed change in strain exceeds a deviation limit, an alarm is activated.

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.

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.

There are provided an apparatus for taking out a molded product that allows a physical amount such as the mass of the taking portion to be easily acquired with a relatively simple configuration. A posture reversing mechanism is provided between the elevating arm and the taking portion to change the direction of the taking portion between an unreversed state in which the taking portion is directed to be able to take hold of the molded product molded in the die, and a reversed state in which the length of the taking portion in the vertical direction is shorter than that in the unreversed state. A sensor detects vibration of the elevating arm. A mass estimating section estimates the mass of the taking portion on the basis of vibration of the elevating arm detected by the sensor when the taking portion is in the reversed state.

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.

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.

A misalignment sensing system for a molding structure and a method for using same. The molding structure includes a first component and a second component, at least one of the components being selectively repositionable between a closed configuration of the mold structure and an open configuration of the mold structure. The misalignment sensing system includes an alignment member including a male portion coupled to and extending from the first component of the molding structure, and a female portion defined in the second component of the molding structure, the female portion being configured to receive the male portion when the molding structure is in a closed configuration; and at least one sensor connected to one of the male and female portions and being configured to detect a deformation of any one of the male portion and the female portion, the deformation being induced by a misalignment of the molding structure.

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.