An injection molding apparatus including: a valve pin driven by an actuator, the valve pin extending axially through at least a portion of the channel length of the fluid flow channel, the fluid flow channel including a throat, downstream flow of the injection fluid being restricted by a bulb portion of the pin, the valve pin having an intermediate position where downstream flow of injection fluid is unrestricted and a fully downstream position where downstream flow of injection fluid is stopped at both the gate and at the throat, wherein the actuator is driven by a valve assembly comprised of a spool mechanically driven by first and second actuators or solenoids that each separately engage the spool at opposing axial ends to effect movement of the spool back and forth between the drive fluid flow positions.

An injection molding apparatus comprising: an injection molding machine, a heated manifold, a nozzle, the downstream end of the nozzle comprising an inner tubular member having a central flow channel and an outer circumferential surface and an outer tubular member having an inner tubular surface, the outer tubular member forming a seal surrounding the gate, the inner and outer tubular members being adapted to form a sealed circumferential gap, the inner tubular member including one or apertures extending radially through the inner tubular member to route flow radially from the fluid flow channel into the circumferential gap.

A runner for supplying resin to a cavity includes a sprue that is supplied resin from a nozzle of an injection molding machine, a first path formed in the runner, where the resin flows in the first path from the nozzle when the nozzle connects to the sprue, a first pin that moves to a first position to increase the size of the first path before the resin is supplied to the first path and moves to a second position to decrease the size of the first path before the nozzle separates from the sprue.

An injection molding apparatus including: a valve pin driven by an actuator, the valve pin extending axially through at least a portion of the channel length of the fluid flow channel, the fluid flow channel and the valve pin being configured or adapted such that the valve pin is movable axially upstream and downstream between an upstream position where the downstream flow of the injection fluid is restricted by a bulbous protrusion (B) of the pin being axially aligned (AL) with the throat (T) of the channel, an intermediate position where downstream flow of injection fluid is unrestricted (WG) and a fully downstream position where downstream flow of injection fluid is stopped at both the gate and at the throat.

An injection molding apparatus comprising: an injection molding machine, a heated manifold, a nozzle, the downstream end of the nozzle comprising an inner tubular member having a central flow channel and an outer circumferential surface and an outer tubular member having an inner tubular surface, the outer tubular member forming a seal surrounding the gate, the inner and outer tubular members being adapted to form a sealed circumferential gap, the inner tubular member including one or apertures extending radially through the inner tubular member to route flow radially from the fluid flow channel into the circumferential gap.

A method and apparatus for equalizing gate pressure of a hot runner nozzle are disclosed. The nozzle includes a nozzle housing defining a primary melt channel, a first nozzle tip having a first secondary melt channel in fluid communication with the primary melt channel, a second nozzle tip having a second secondary melt channel in fluid communication with the primary melt channel, and a valve disposed in the primary melt channel for selectively opening and closing a downstream end of the primary melt channel to control a flow of melt to the first and second secondary melt channels. In some embodiments, the valve is configured to selectively open when a pressure of the melt reaches a threshold peak pressure. In some embodiments, the valve includes a valve stem that cooperates with the primary melt channel to block a flow of melt therefrom until the threshold peak pressure is established.

An injection molding apparatus including: a valve pin driven by an actuator, the valve pin extending axially through at least a portion of the channel length of the fluid flow channel, the fluid flow channel and the valve pin being configured or adapted such that the valve pin is movable axially upstream and downstream between an upstream position where the downstream flow of the injection fluid is restricted by a bulbous protrusion (B) of the pin being axially aligned (AL) with the throat (T) of the channel, an intermediate position where downstream flow of injection fluid is unrestricted (WG) and a fully downstream position where downstream flow of injection fluid is stopped at both the gate and at the throat.

An injection molding apparatus including: a valve pin driven by an actuator, the valve pin extending axially through at least a portion of the channel length of the fluid flow channel, the fluid flow channel including a throat, downstream flow of the injection fluid being restricted by a bulb portion of the pin, the valve pin having an intermediate position where downstream flow of injection fluid is unrestricted and a fully downstream position where downstream flow of injection fluid is stopped at both the gate and at the throat, wherein the actuator is driven by a valve assembly comprised of a spool mechanically driven by first and second actuators or solenoids that each separately engage the spool at opposing axial ends to effect movement of the spool back and forth between the drive fluid flow positions.

Injecting a resin from a hot runner connected to a recessed shape into a space surrounded by a surface having a shape of a transferred outer surface, a surface having a shape of a transferred non-outer surface that opposes the surface having the shape of the transferred outer surface, and the recessed shape that is recessed with respect to the surface having the shape of the transferred non-outer surface, advancing a valve pin to a position away from the non-outer surface by a distance in a range of 50% to 150%, inclusive, of a basic wall thickness of the recessed shape.

A runner for supplying resin to a cavity includes a sprue that is supplied resin from a nozzle of an injection molding machine, a first path formed in the runner, where the resin flows in the first path from the nozzle when the nozzle connects to the sprue, a first pin that moves to a first position to increase the size of the first path before the resin is supplied to the first path and moves to a second position to decrease the size of the first path before the nozzle separates from the sprue.