Abstract: A molded article is formed using an injection molding apparatus by heating a thermoplastic material to a melt temperature, injecting the heated thermoplastic material into at least one mold cavity of an injection molding apparatus at a substantially constant pressure, and cooling the thermoplastic material to an ejection temperature. The thermoplastic material is heated to a reduced melt temperature which is less than a minimum conventional melt temperature.

Abstract: A method of controlling a melt pressure of an injection molding apparatus is provided. The method includes establishing a melt pressure profile having a plurality of setpoints.

Abstract: A process of forming molded articles using an injection molding apparatus is provided. The process includes providing a thermoplastic material to the injection molding apparatus. The thermoplastic material is heated such that the thermoplastic material is in a molten state. The molten thermoplastic material is injected into at least one mold cavity of the injection molding apparatus using an injection element. Melt pressure of the thermoplastic material filling the at least one mold cavity is monitored using a sensor. The sensor provides a signal indicative of melt pressure to a controller. The controller controls introduction of a non-reactive additive to the thermoplastic material thereby changing a viscosity of the molten thermoplastic material based on the signal. A molded article is formed by reducing a mold temperature of the thermoplastic material within the at least one mold cavity.

Abstract: A injection molding method involves measuring, using at least one strain gauge sensor, a change in strain in a mold side of a mold cavity, approximating a pressure within the mold cavity based on the change in strain, comparing the approximated pressure to a pre-set trigger point, and if the approximated pressure equals or exceeds the pre-set trigger point, activating a virtual cavity sensor having an optimal pre-defined pressure-time curve, wherein upon activation, the virtual cavity sensor tracks approximated pressures calculated from the change in strain measurements measured by the at least one strain gauge sensor over time and compares the results of the approximated pressure tracking to the optimal pre-defined pressure-time curve.

Abstract: A injection molding method involves measuring, using at least one external sensor, a change in a parameter of a mold side of a mold cavity, approximating a condition within the mold cavity based on the change in the parameter, such as pressure within the mold cavity or flow front position, and comparing the approximated condition to a trigger point,. If the approximated condition equals or exceeds the trigger point, activating a virtual cavity sensor having an optimal pre-defined pressure-time curve, and upon activation, the virtual cavity sensor tracks an approximated condition calculated from the change in parameter measurements measured by the at least one external sensor over time. In an embodiment, results of the approximated parameter tracking can be used in conjunction with an optimal pre-defined pressure-time curve.

Abstract: Injection molding at substantially constant pressure yields a substantially controlled injection molding process, even when utilizing a leaking check ring.

Abstract: Injection molding at substantially constant pressure and utilizing “sequential coining” to produce molded parts substantially free of cosmetic and mechanical defects.

Abstract: In order to injection mold parts at a constant flow front velocity in a mold cavity of an injection molding system, particularly where the mold cavity has a varying thickness along its length, mold modeling software is used to calculate the cross-sectional area as a function of the distance from the gate, percentage of fill, or length of the mold cavity. Based on that cross-sectional area, the mold modeling software determines an appropriate recommended ram force profile and/or melt pressure profile that would result in filling the mold cavity at a constant flow rate. An injection molding system is then operated according to the recommended ram force profile and/or melt pressure profile.

Abstract: A method and a machine that account for changes in material properties of molten plastic material during an injection run. If viscosity of the molten plastic material changes during an injection run, a controller alters a step time of the injection cycle to ensure that molten plastic material completely fills and packs a mold cavity to prevent part flaws such as short shots or flashing.

Abstract: A method and a machine that account for changes in material properties of molten plastic material during an injection run. If viscosity of the molten plastic material changes during an injection run, a controller alters a step time of the injection cycle to ensure that molten plastic material completely fills and packs a mold cavity to prevent part flaws such as short shots or flashing.

Abstract: An injection mold assembly for a high output consumer product injection molding machine, the injection mold assembly having a simplified cooling system. The simplified cooling system has a cooling complexity factor of less than three, preferably less than two, more preferably less than one.

Abstract: A substantially constant pressure injection molding method and machine that forms molded parts by injecting molten thermoplastic material into a mold cavity at a substantially constant pressure. As a result, the mold cavity is filled with molten thermoplastic material by advancing a continuous flow front of thermoplastic material from a gate to an end of the mold cavity.

Abstract: A variable-position mold system with a plurality of injection systems operable to deliver molten material at a substantially constant pressure of between about 6.89 megapascals (1,000 psi) and about 103.42 megapascals (15,000 psi) to a set of mold cavities of at least one multi-cavity injection mold insert when in fluid communication therewith. The multi-cavity injection mold inserts have a thermal conductivity of greater than 30 BTU/HR FT ° F., and have little or no cooling channels therein.

Abstract: A method and a machine that account for changes in material properties of molten plastic material during an injection run. If viscosity of the molten plastic material changes during an injection run, a controller alters an injection pressure to ensure that molten plastic material fills a mold cavity within a correct amount of time to prevent part flaws such as short shots or flashing.

Abstract: An injection molding machine that uses a mold and a native controller to operate according to an original mold cycle to mold plastic objects is retrofitted with a retrofit controller; the retrofitted machine uses the mold and the retrofit controller to operate according to a retrofit mold cycle to mold plastic objects.

Abstract: An injection molding machine that uses a mold and a native controller to operate according to an original mold cycle to mold plastic objects is retrofitted with a retrofit controller; the retrofitted machine uses the mold and the retrofit controller to operate according to a retrofit mold cycle to mold plastic objects. The retrofit mold cycle has a maximum injection pressure that is less than a maximum injection pressure of the original mold cycle. The retrofit mold cycle can also have more constant injection pressures than the original mold cycle.

Abstract: An injection molding machine that uses a mold and a native controller to operate according to an original mold cycle to mold plastic objects is retrofitted with a retrofit controller; the retrofitted machine uses the mold and the retrofit controller to operate according to a retrofit mold cycle to mold plastic objects.

Abstract: An injection molding machine that uses a mold and a native controller to operate according to an original mold cycle to mold plastic objects is retrofitted with a retrofit controller; the retrofitted machine uses the mold and the retrofit controller to operate according to a retrofit mold cycle to mold plastic objects. When molding according to the retrofit mold cycle, the injection molding machine can obtain a faster cycle time.

Abstract: An injection molding machine that uses a mold and a native controller to operate according to an original mold cycle to mold plastic objects is retrofitted with a retrofit controller; the retrofitted machine uses the mold and the retrofit controller to operate according to a retrofit mold cycle to mold plastic objects. When molding according to the retrofit mold cycle, the injection molding machine uses lower temperatures, when compared to molding according to the original mold cycle.

Abstract: A melt pressure regulating mechanism for an injection molding apparatus having a melt holder for pressurizing molten plastic prior to injection into a mold, the molten plastic having a melt pressure, and an injection element for advancing the molten plastic from the melt holder through a nozzle and into the mold, the melt pressure regulating mechanism comprising a pressure regulating device, comprising at least one of a fluid pressure regulating valve and a pressure relief valve.