A method of injection molding of plastic materials into a cavity of a mold with a molding apparatus including a distributor of the pressurized fluid plastic material connected to at least one injector having a pin valve displaceable between a fully closed position and an open position. The method includes a filling step following displacement of the pin valve from the fully closed position to the open position, a packing step of the pressurized plastic material keeping the pin valve in the open position, and a step of displacement and maintenance of the pin valve in at least one partially closed intermediate position prior to its complete closure.

The invention relates to a system for controlling a shutter (110) slidably arranged in a plastic material injection nozzle (11), comprising a rotary electric motor (M) and a mechanism adapted to couple said motor (M) to the shutter to slidably drive it between a closing position of the nozzle and a maximum opening position of the nozzle, characterised in that said mechanism comprises: an eccentric (21) integral with an output shaft (20) of the motor so as to be rotationally driven by said output shaft, comprising a crank pin (22) parallel to the output shaft but non-coaxial with said shaft (20), a slide (23) adapted to be made integral with one end of the shutter (110), and a connecting rod (25), a first end of which is articulated on the crank pin (22) of the eccentric (21) and a second end is articulated on an axis (25b) of the slide (23) such that the rotation of the eccentric causes sliding of the oscillating shutter between the closing position and the maximum opening position.

The invention relates to a system for controlling a shutter (110) slidably arranged in a plastic material injection nozzle (11), comprising a rotary electric motor (M) and a mechanism adapted to couple said motor (M) to the shutter to slidably drive it between a closing position of the nozzle and a maximum opening position of the nozzle, characterised in that said mechanism comprises: an eccentric (21) integral with an output shaft (20) of the motor so as to be rotationally driven by said output shaft, comprising a crank pin (22) parallel to the output shaft but non-coaxial with said shaft (20), a slide (23) adapted to be made integral with one end of the shutter (110), and a connecting rod (25), a first end of which is articulated on the crank pin (22) of the eccentric (21) and a second end is articulated on an axis (25b) of the slide (23) such that the rotation of the eccentric causes sliding of the oscillating shutter between the closing position and the maximum opening position.

A shut-off nozzle includes: an injection nozzle in which a flow path is formed; a needle valve provided in the flow path coaxially with the injection nozzle, the needle valve being movable forward and backward in an axial direction; and a guide ring provided in the flow path. The needle valve includes a columnar shaft portion, and the guide ring is configured to guide the forward and backward movement of the needle valve at the shaft portion. An injection device includes: a heating cylinder; a screw provided in the heating cylinder; and the shut-off nozzle provided in the heating cylinder. An injection molding machine includes: a mold clamping device configured to clamp a mold; and the injection device configured to inject a resin.

A shut-off nozzle includes: an injection nozzle in which a flow path is formed; a needle valve provided in the flow path coaxially with the injection nozzle, the needle valve being movable forward and backward in an axial direction; and a guide ring provided in the flow path. The needle valve includes a columnar shaft portion, and the guide ring is configured to guide the forward and backward movement of the needle valve at the shaft portion. An injection device includes: a heating cylinder; a screw provided in the heating cylinder; and the shut-off nozzle provided in the heating cylinder. An injection molding machine includes: a mold clamping device configured to clamp a mold; and the injection device configured to inject a resin.

A method of manufacturing an article using injection molding includes a step of injecting resin from an injection nozzle having a valve pin via a resin flow path in a first mold (metal mold) into a cavity in the first mold, a step of inserting the valve pin into the resin flow path, extracting the valve pin from the resin flow path, starting to increase a distance between the injection nozzle and the first mold after extracting the valve pin, and a third step of, after starting to increase the distance between the injection nozzle and the first mold, injecting resin from the injection nozzle via a resin flow path in a second mold into a cavity in the second mold.

A molding apparatus for molding an opening device onto a packaging material web comprises at least one mold unit couplable to the packaging material web; and an injection device configured to inject molten polymer into the mold unit. The injection device comprises a cavity configured to receive the molten polymer, an inlet configured to allow for introduction of the molten polymer into the cavity, a first outlet configured to allow for an outflow of a first portion of the molten polymer from the cavity, a first valve element configured to selectively open and close the first outlet, a second outlet configured to allow for an outflow of a second portion of the molten polymer from the cavity, a second valve element configured to selectively open and close the second outlet and a pressurizing unit in fluidic connection with the cavity and configured to pressurize the molten polymer within the cavity.

A method for manufacturing an impeller with a number of impeller blades and a cover disc covering the impeller blades. Plastic is injected into an injection mold using a cascade injection molding process to form the impeller. The injection mold has a number of shut-off nozzles to feed the plastic at various joint positions and different opening times. The number of shut-off nozzles is determined as a function of the number of impeller blades.

An injection nozzle is attachable to a tip end of a heating cylinder and having an in-nozzle flow path formed therein. The injection nozzle is attached to the heating cylinder by being pressed against the heating cylinder by a nozzle pressing member that is fixed to an end surface of a tip end of the heating cylinder. An outer peripheral surface of the injection nozzle has a sensor hole that is opened at a position contacting the nozzle pressing member, and a temperature sensor is inserted into the sensor hole.

A manufacturing apparatus includes a defining portion, a plunger, and a valve member. The defining portion defines a supply port, a discharge port, and a resin channel. The resin channel includes a reserving portion, a first partial channel connecting the supply port and the reserving portion, a second partial channel connecting the reserving portion and the discharge port, a relay channel connecting the first partial channel, the reserving portion and the second partial channel, and a connecting channel connecting the first partial channel and the second partial channel. The plunger discharges the molten resin reserved in the reserving portion. The valve member is provided in the connecting channel and the second partial channel. The first partial channel and the relay channel are connected to the connecting channel so as to intersect with the connecting channel. The valve member includes a first valve portion and a second valve portion.