Disclosed is a guide bushing for the guiding and sealing of a closing needle of a needle valve nozzle of an injection moulding apparatus, the guide bushing having a main part and a fastening element, wherein the main part has a through-opening for the closing needle, wherein the through-opening comprises at least one guiding portion, which encloses the closing needle with slight movement play, wherein the through-opening comprises at least two expansion portions, whose diameter in each case is larger than that of the at least one guiding portion. The guide bushing moreover comprises a fastening element, which is securable to the main part, wherein a seal element is arranged between the fastening element and the main part, bearing against the entire circumference of a closing needle inserted into the through-opening.

An injection molding apparatus and method for adjusting the axial position of a valve pin in an injection molding system, the apparatus comprising: a top clamp plate, a heated manifold receiving and distributing an injection fluid to an exit of a fluid delivery channel to a cavity of the mold, an actuator comprising a housing having a chamber enclosing a drive member for driving a valve pin along an axial path of travel, the actuator housing slidably mounted and adapted for controlled upstream and downstream movement of the drive member along a path complementary to the axial path of travel of the valve pin, a mounting plate and an axial position adjustment screw screwably mounted within the mounting plate upstream of the housing of the actuator for controllably moving the valve pin to selectable starting or ending injection cycle axial positions.

Systems and methods for controlling the closing speed of valve gated nozzles are disclosed. In one embodiment, a hot runner have a valve gated nozzle including a valve stem movable between an open position and a closed position is provided. The valve stem is moved at a first speed for a first portion of valve stem closure and a second speed for a second end portion of the valve stem closure.

Injection unit for injection molding of plastic material including: an injection nozzle; a closure pin; and a guide and cooling assembly, interposed between the back driving plate and the hot distribution plate, in turn comprising: a guide and seal element for guiding the axial motion of the closure pin; a cooling ring; and pressure means configured to press the cooling ring directly and against the back driving plate; wherein the guide and seal element is slidably coupled, at an upper end, with a central hole of the cooling ring, and is fixed integrally, at the other end, to the hot distribution plate; and the cooling ring is able to slide laterally with respect to the back driving plate to recover the differences in thermal expansion between the hot distribution plate and the back driving plate and to transmit heat from the guide and seal element towards the back driving plate.

A tool holder is provided comprising a base body for coupling with a drive spindle that can be driven rotatingly, whereon a clamping chuck for clamping a tool is provided, further comprising a damping element arranged between the base body and the clamping chuck, wherein the damping element is made of an elastomeric material or of a shape memory alloy, and wherein the clamping chuck is solely connected to the base body by means of the damping element.

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.

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.

Apparatus and method for performing an injection molding cycle using the apparatus where the apparatus comprises: a manifold, a pneumatic actuator driven by a pneumatic valve assembly, the actuator driving a valve pin between a gate closed position and a maximum injection fluid flow position, the pneumatic valve assembly having a spool supported within a cylinder driven by a drive device that is supported solely by and translates together with the spool, a controller that instructs the pneumatic valve assembly to cause the actuator to drive the valve pin either upstream or downstream to selected positions or at selected velocities during the course of a single injection cycle based on a feedback signal indicative of position of the pin or actuator or pressure of an injection fluid material.

An injection molding apparatus (10) comprising: a heated manifold (16), one or more fluid driven actuators (210a, 210b) each interconnected to a corresponding valve pin (211a, 211b), a housing comprised of one or more metal plates (202a, 202b, 204a, 204b, 206) arranged to form a manifold chamber (208), each of the fluid driven actuators (210a, 210b) being mounted within or at least about one foot from within the manifold chamber (208), each fluid driven actuator being fluid drive interconnected to a proportional control valve (213a, 213b, 213c) that is mounted either within the manifold chamber (208) or having fluid flow ports (213p1, 213p2) that are interconnected within about one foot of corresponding fluid flow ports (210p1, 210p2) of a corresponding fluid driven actuator (210a, 210b).