A method and apparatus for producing hollow articles made of injection moulded plastic material by a mould having a die within which there is inserted a core, and at least one injector including a pin valve displaceable between a closing position and an opening position for injecting the pressurized plastic material into a space comprised between the die and the core. During the injection, any flexural deflection of the core is detected and the pin valve of the or of each injector is displaced in a controlled fashion to adjust a pressure and a flow rate of the injected plastic material, so as to reduce or eliminate such deflection of the core.

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.

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.

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.

Injection molding apparatus (1) comprising: an actuator (14, 940, 941, 942) comprising a rotor (940r, 941r, 942r) controllably rotatable by electric power, the actuator (14, 940, 941, 942) being interconnected to a controller (16) that generates drive signals (DC), an electrical drive device (940d, 941d, 942d) comprising an interface that receives the drive signals (DC) and controllably distributes electrical energy or power in controllably varied amounts according to the drive signals (DC) to a driver (940dr, 941dr, 942dr) that drives the rotor (940r, 941r, 942r), a valve pin (1040, 1041, 1042) having an axis (X) and a control surface (43, 45, 102m) adapted to interface with a complementary surface (47, 103s) in a downstream feed channel to vary rate of injection fluid flow to a cavity of a mold, and, a sensor adapted to sense a property of the injection fluid upstream and away from a gate, the sensed property being used in a program to controllably position the control surface relative to the complementary surface.

In the present invention, sealing tape is wrapped around the outer circumferential surface of an introduced mold, and a monomer solution is injected into a cavity formed therein, wherein the injection amount of the monomer solution can be precisely controlled by using a vision recognition system. According to a preferable embodiment, a monomer solution of a monomer solution tank is suctioned, in advance, into a syringe capable of adjusting a capacity corresponding to a mold; most of the monomer solution, which has been injected into the syringe, is firstly injected into the mold at a high injection flow rate or injection speed; while the residual amount of the monomer solution is secondly injected at a reduced injection flow rate or injection speed, it is finally confirmed, by using a vision recognition system, whether the monomer solution is filled in the mold; and then injection is finished.

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.

According to one embodiment, a mold includes a substrate clamping surface, a cavity, a suction part, a vent, an intermediate cavity, and an opening/closing part. The substrate clamping surface contacts a surface of a processing substrate. The cavity is recessed from the substrate clamping surface. The suction part is recessed from the substrate clamping surface. The vent is provided on a path between the cavity and the suction part, communicates with the cavity, is recessed from the substrate clamping surface to a vent depth. The intermediate cavity is provided between the vent and the suction part on the path, communicates with the vent, and is recessed from the substrate clamping surface to an intermediate cavity depth deeper than the vent depth. The opening/closing part opens and closes the path and is provided between the intermediate cavity and the suction part on the path.

The present invention discloses a ultrasonic method for indirectly measuring a pressure of a cavity of an injection molding machine, comprising: emitting ultrasonic wave to each pull rod along an axial direction of the pull rod respectively at the same time, detecting an ultrasonic wave echo time difference of each pull rod, and obtaining an average pressure inside a cavity of the injection molding machine. By the detection method and detection device of the present invention, the pressure inside the cavity may be detected in a certain state, the pressure inside the cavity in the injection molding process may be detected in real time, and the detection process is simple and the accuracy is high.

A system and method for determining the position of a flow of melt within an injection molding system comprises a switch and a pin that actuates the switch. The pin has a first end positioned closer to the anticipated flow path of the melt and a second end that is positioned to be in contact with the switch, such that when melt enters the anticipated flow path, the pin is pushed to activate the switch.