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 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.

A measuring arrangement for a shaping machine includes a measuring diaphragm deformable by a force action, a measuring device for metrological detection of a deformation of the measuring diaphragm with the output of a measurement signal, and an evaluation device connected to the measuring device. The evaluation device, in the course of a first calibration, can convert the measurement signal originating from the deformation of the measuring diaphragm with a force from a first force value range into a first output signal, and the first output signal is in a previously defined value range. The evaluation device, in the course of a second calibration, can convert the measurement signal originating from the deformation of the measuring diaphragm with a force from a second force value range differing from the first force value range into a second output signal, and the second output signal is in the previously defined value range.

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, whereupon a cure profile is commenced.

A method and system for adjusting melt pressure in an injection molding material that allows calculating a melt pressure of a molten plastic material to be injected and based on the calculated melt pressure and a desired melt pressure adjusting operation of an injection molding machine. This control of an injection molding cycle using the method and system of plastic melt pressure determination allows production of parts of increased quality and consistency.

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 of monitoring and controlling a sequential valve gate molding 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 first valve gate from a first strain gauge, identifying whether a deviation exists from a first portion of the target strain profile based on the output from the first strain gauge, determining whether any existing deviation exceeds the deviation limit, and adjusting the position of a first valve gate pin in the first valve gate if it does. The method may further include control of subsequent valve gates. Multiple strain gauges may be used to control a single valve gate, and/or each strain gauge may control more than one valve gate.

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.

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.