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.

A method and apparatus for performing an injection molding cycle comprising drivably interconnecting a valve pin to an electric motor actuator and controllably operating the electric motor to drive the valve pin at one or more reduced rates of upstream or downstream travel based on either detection of the position of the pin or actuator or on a preselected length of time at which to drive the valve pin.

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.

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.

The injection moulding of articles formed by plastic materials having different characteristics, for example of different colours, is carried out in a single injection cycle in which the first and the second plastic materials are injected into a first and into a second zone of a mould cavity by first and second injectors controlled according to specific modes so as to define a shape and/or a position of a weld line.

An apparatus for controlling the rate of flow of mold material to a mold cavity, the apparatus comprising: an injection molding machine and a manifold; an actuator interconnected to a valve pin having a tip end; a valve system in fluid communication with the actuator to drive the actuator at one or more rates of travel, the valve system having a start position, one or more intermediate drive rate positions and a high drive rate position, the start position holding the valve pin in a gate closed position; a controller that instructs the valve system to move from the start position to the one or more intermediate drive rate positions and to remain in the one or more intermediate drive rate positions for one or more corresponding predetermined amounts of time.

Apparatus and method for detecting a position of an actuator piston driving a valve pin in an injection molding system. The apparatus includes an actuator housing having a body portion, surrounding an axial bore, of a substantially non-magnetic and/or magnetically permeable material, a piston, movable within the axial bore for driving a valve pin, the piston including a magnetic member generating a magnetic field such that axial movement of the piston in the bore modifies the magnetic field according to the position of the piston relative to a detection position, and a magnetic field detector attached to an exterior surface of the body portion at the detection position for detecting the magnetic field associated with the position of the piston and generating an output signal determined by the piston position.

Apparatus and method for detecting a position of an actuator piston driving a valve pin in an injection molding system. The apparatus includes an actuator housing having a body portion, surrounding an axial bore, of a substantially non-magnetic and/or magnetically permeable material, a piston, movable within the axial bore for driving a valve pin, the piston including a magnetic member generating a magnetic field such that axial movement of the piston in the bore modifies the magnetic field according to the position of the piston relative to a detection position, and a magnetic field detector attached to an exterior surface of the body portion at the detection position for detecting the magnetic field associated with the position of the piston and generating an output signal determined by the piston position.

An apparatus for controlling the rate of flow of a fluid mold material comprising: a manifold, an actuator interconnected to a valve pin, a position sensor that senses position of the valve pin, a controller that controls movement of the actuator according to instructions that instruct the actuator to drive the valve pin upstream at one or more selected intermediate velocities in response to receipt by the controller of a signal from the position sensor that the valve pin is disposed in the one or more intermediate upstream gate open positions.

An injection molding device includes an injection device including a cylinder, a screw, and a nozzle provided at a front end of the cylinder, for discharging molten resin as the screw advances, a mold including a molded product cavity, and a resin channel between the molded product cavity and a portion abutting the nozzle, a channel pressure measuring device for acquiring channel pressure data in the resin channel, and a determination unit that determines presence/absence of clogging of a gate of the resin channel, based on features of the channel pressure data.