An injection apparatus includes (a) a barrel; (b) a nozzle at a front end of the barrel; (c) a screw in the barrel; and (d) a drive assembly including: (i) a housing having a front end coupled to the barrel; (ii) a spindle in the housing and fixed to the screw; (iii) a first motor in the housing and having a hollow first rotor through which the spindle passes. The first rotor is coupled to the spindle for driving rotation of the screw about the axis. The drive assembly further includes (iv) a second motor in the housing axially rearward of the first motor. The second motor has a hollow second rotor through which the spindle passes. The second rotor is coupled to the spindle for translating the screw along the axis in response to rotation of the second rotor relative to the spindle.

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.

The disclosure relates to a method for producing an optical element having at least one optically effective surface. The optically effective surface comprises a contour and a surface structure superimposed on the contour. Transparent liquid plastic is injection-molded by means of a (smooth) injection mold of an injection molding machine (500) in dependence on a group of injection molding parameters to form an injection molded component (21) having the contour of the optically effective surface but without the surface structure superimposed on the contour, wherein at least one parameter of the group of injection molding parameters is set and/or corrected in dependence on properties of the injection molded component (21), and wherein the optical element is produced using the group of injection molding parameters.

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 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.

An Injection molding apparatus injection molding apparatus (10a) comprising: one or more first downstream channels (166, 166a, 166b) and associated first gates (34, 34a, 34b) that deliver injection fluid (18) to a first cavity (300a) of a mold system (302, 303) and to one or more second downstream channels (168, 168a, 168b) and associated second gates (32, 32a, 32b) that deliver injection fluid to a second cavity (300b) of the mold system (302, 303), the mold system being clamped together under a selected force, the apparatus including a first upstream valve (118) that enables and disables flow of the injection fluid to the first gates (34, 34a, 34b) and a second upstream valve (108) that enables and disables flow of the injection fluid to the one or more second gates (32, 32a, 32b),
the apparatus including a control system (20) adapted to open or enable flow of the injection fluid (18) to the one or more first gates (34, 34a, 34b) at a first selected time and to further instruct the second upstream valve (108) to open or enable flow of the injection fluid (18) to the one or more second gates (32, 32a, 32b) at a second selected time that is delayed relative to the first selected time during the course of an injection cycle.

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 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.

When an injection molding machine performs molding, the mold clamping force on the mold is adjusted on the basis of a mold displacement of the mold or the injection peak pressure and injection foremost position so that the molding is performed without causing flash and by an appropriate mold clamping force with which energy can be reduced. The amount of mold displacement and also the injection peak pressure and the injection foremost position are monitored during automatic operation. If there occurs no mold displacement change exceeding a threshold or if there occurs no injection peak pressure anomaly or injection foremost position anomaly exceeding thresholds, the automatic operation is continued. If the mold displacement change occurs or if the injection peak pressure anomaly and the injection foremost position anomaly occur, the operation of the injection molding machine is stopped.