An injection molding apparatus including an actuator interconnected to a rod or valve pin having a smooth continuous cylindrical outer surface and one or more discontinuous or relieved or relieved portions formed as discontinuities in the cylindrical outer surface and adapted to be disposed within a fluid flow channel, the one or more discontinuous or relieved portions being configured and arranged along the axial length of the pin or rod such that the flow of injection fluid over or past the one or more discontinuous or relieved portions is modified to flow at substantially different rates or velocities or in substantially different flow patterns relative to rate or velocity or pattern of flow of injection fluid over or past the smooth continuous cylindrical outer surface.

An injection molding apparatus has a mold tool that is positioned around a field joint of a pipeline to define a mold cavity. Two or more pumping chambers communicate with the mold tool. Each chamber is expansible to draw in molten polymer and contractible to drive the polymer into the mold cavity. Expansion of one chamber is synchronized with contraction of another chamber. The operation of supply and injection valves associated with the chambers is also synchronized, both with each other and with expansion and contraction of the chambers. In the embodiment described, two pumping chambers are defined within a common pressurizing cylinder, in which the chambers are separated by a piston. The piston is movable within the cylinder to determine and to synchronize expansion and contraction of the chambers.

A moving-body monitoring device has a position detection unit that outputs positional information of a moving body, a proximity sensor that detects the moving body, a first storage unit that stores a position when the moving body having moved in a first direction is detected as first positional information, and stores a position when the moving body having moved in a second direction is detected as second positional information, and a calculation unit that calculates a fixed-point position of a detecting region of the proximity sensor during monitoring as fixed-point positional information based on the first and second positional information. The device also has a second storage unit that stores reference fixed-point positional information, and a monitoring unit that, when a deviation between the fixed-point and reference fixed-point positional information goes beyond a stipulated range, determines that a positional deviation amount of the moving body exceeds a tolerance.

A work holding mechanism includes a body part having a three-dimensional shape including at least a recess or a protrusion, and an adsorption part for holding a work by adsorbing the work onto the body part in conformity to the three-dimensional shape of the recess or the protrusion provided in the body part. The work is held by being adsorbed in conformity to the three-dimensional shape of the body part, and, therefore, the amount of usage of the work in a work molding system can be reduced as compared with when the work is held so as to have a flat shape.

An injection molding method includes: a plasticizing process of feeding a resin pellet and additive components to a heating cylinder including a screw that can rotate around a rotation axis and can advance and retreat along the rotation axis, and generating molten resin by rotating the screw in a normal direction; and an injection process of injecting to a cavity the molten resin containing the additive components. In the plasticizing process, retreat operation of forcibly retreating the screw is performed at a predetermined velocity by a predetermined stroke or a predetermined time.

The invention relates to an apparatus (1) for injection molding, said apparatus comprising -a mold cavity member (20) having a mold cavity (22), -a melt channel, -an injection chamber (16) and -an injection gate having an injection gate hole (24). The apparatus further comprises a movable injection sleeve (10) and furthermore -the melt channel is configured for providing a flow of molten material from a source of molten material to an injection chamber (16), -the apparatus (1) is configured for transferring the molten material from the injection chamber (16) to the mold cavity (22) via said injection gate hole (24), said injection gate being controllable by a forward part of a movable filling valve (6), and -the injection chamber (16) has a volume that is controllable by movement of the movable injection sleeve (10). The invention further relates to a method of injection molding.

Provided is a molding machine including a mold opening/closing mechanism configured to move a movable platen to be attached with a movable mold to a stationary platen to be attached with a stationary mold, and a clamping mechanism to perform a clamping process, and is intended to suppress machine cost or ensure the mold opening/closing speed. The molding machine includes the mold opening/closing mechanism configured to move the movable platen to be attached with the movable mold to the stationary platen to be attached with the stationary mold, and the clamping mechanism configured to perform a clamping process. The mold opening/closing mechanism includes at least two ball screws, at least two electric motors that respectively drive the ball screws, and a ball screw nut into which each of the ball screws is inserted.

Injection molding apparatuses and methods wherein a valve pin is controllably driven upstream and downstream along an axis between a first closed position where the tip end of the valve pin obstructs the gate to prevent the injection fluid from flowing into the cavity, a full open position and one or more intermediate positions, wherein the valve pin is drivable to be disposed or held in a selected intermediate position for a selected period of time during the course of an injection cycle where the tip end of the valve pin restricts flow of injection fluid through the gate to the mold cavity.

A die casting machine includes a plurality of ejector pins capable of advancing and retracting together with respect to the internal portion of a die; an electric motor capable of driving the plurality of ejector pins; a position sensor capable of detecting the positions of the plurality of ejector pins; a force sensor capable of detecting the pressure which is given to the molding material inside the die by the plurality of ejector pins; a display device capable of displaying images, and a control device controlling the electric motor and display device. The control device includes a drive control part which controls the electric motor so as to generate a driving force making the plurality of ejector pins advance to the inside of the die after the start of injection and before die opening, and a display control part which controls the display device so as to display the position detected by a position sensor and the pressure detected by a force sensor along a common time axis.

A method and apparatus for injection molding of plastic material into a cavity of a mold by means of at least one injector whose opening and closing occurs through an electronic control unit and wherein an undesired opening of the mold caused by any overpressure of the plastic material injected into the cavity of the mold is detected by means of transducers and corrected by means of the electronic control unit. The transducers are arranged outside the cavity of the mold.