Abstract:
A method and apparatus of controlling commencement of an injection of a melt stream of moldable material from an auxiliary injection unit. A sensor is placed in an injection molding system to sense a condition related to an injection of a first melt stream of a first moldable material provided by a primary injection unit. Commencement of a second melt stream of a second moldable material from the auxiliary injection unit is initiated upon the sensed condition related to the injection of the first melt stream being detected at a preselected value. The sensed condition may be a pressure, velocity or temperature of the first melt stream as provided by a direct sensor, a force or strain on a hot runner component as provided by an indirect sensor or the occurrence of a function of the injection molding system as provided by a functional sensor.
Abstract:
A method for filling at least one cavity of a tool for producing a preform from a melted mass, specifically a cavity of a tool in an injection molding machine, the melted mass being introduced into the cavity under pressure from a plurality of nozzles. According to the method, a sensor is associated with at least one nozzle, the sensor determining the flow of melted mass in the cavity, and the filling process through the nozzles is automatically co-ordinated on the basis of the signals of the sensor.
Abstract:
Apparatus for controlling the rate of flow of fluid material through an injection molding flow channel leading to a gate of a mold cavity, the apparatus comprising: a pin having a longitudinal length being adapted for back and forth axial movement through the flow channel; the pin having a protrusion having a maximum diameter circumferential surface; the channel having an interior surface complementary to the maximum diameter circumferential surface of the protrusion; the pin being slidable to a position within the channel such that the maximum diameter circumferential surface of the protrusion forms a seal with the complementary interior surface portion of the channel to stop flow of the fluid material, an electrically powered actuator interconnected to and controllably driving the pin through the channel.
Abstract:
Method and apparatus for controlling the delivery of polymer material in a sequential injection molding process. In one embodiment, the method provides: delivering a first shot of a first material simultaneously to a plurality of mold cavities; independently sensing for each cavity a property that is indicative of a volume or flow of material that is delivered to the corresponding cavity during the step of delivering the first shot; independently stopping the step of delivering the first shot to one or more cavities according to a program that uses as a variable a signal indicative of the property sensed for the corresponding cavity during delivery of the first shot; and delivering a second shot of a second material simultaneously to the cavities subsequent to the step of stopping the step of delivering the first shot.
Abstract:
Method and apparatus for controlling the delivery of polymer material in a sequential injection molding process. In one embodiment, the method provides: delivering a first shot of a first material simultaneously to a plurality of mold cavities; independently sensing for each cavity a property that is indicative of a volume or flow of material that is delivered to the corresponding cavity during the step of delivering the first shot; independently stopping the step of delivering the first shot to one or more cavities according to a program that uses as a variable a signal indicative of the property sensed for the corresponding cavity during delivery of the first shot; and delivering a second shot of a second material simultaneously to the cavities subsequent to the step of stopping the step of delivering the first shot.
Abstract:
An injection molding apparatus for delivering a melt stream of moldable material to a mold cavity. A valve pin extends through a melt channel of the apparatus that is axially movable to control the melt stream within the melt channel and/or to selectively open a gate to allow communication with the mold cavity. A processing sensor is coupled to the valve pin and is axially movable therewith. By example, the processing sensor may be a pressure sensor and/or a temperature sensor for sensing processing condition(s) of the melt stream and providing sensed information to a controller.
Abstract:
An injection molding system includes a manifold and a valve gated hot runner nozzle. The gating mechanism includes an actuated valve pin, where the mold gate orifice is open when the valve pin is in a first position to allow melt to flow there through. The mold gate orifice is closed when the valve pin is in a second position to prevent melt from flowing there though. A flow control pin is disposed within the melt stream, either coaxially with the valve pin within the melt channel of the nozzle or within the manifold melt channel. The flow control pin has a head with a complementary geometry with that of the melt channel at a flow control surface. The flow control pin is raised and lowered by an actuation mechanism to constrict or release the flow of the melt stream independent from the movement of the valve pin.
Abstract:
An injection molding apparatus and method are provided in which the rate of material flow during an injection cycle is controlled. According to one preferred embodiment, an injection molding apparatus is provided that includes a manifold, at least one injection nozzle coupled to the manifold, an actuator, and a valve pin adapted to reciprocate through the manifold and the injection nozzle. The valve pin has a first end coupled to the actuator, a second end that closes the gate in a forward position, and a control surface intermediate said first and second ends for adjusting the rate of material flow during an injection cycle. Retracting the valve pin tends to decrease the rate of material flow during the injection cycle and displacing the valve pin toward the gate tends to increase the rate of material flow during the injection cycle.
Abstract:
An injection molding apparatus and method are provided in which the rate of material flow during an injection cycle is controlled. According to one preferred embodiment, an injection molding apparatus is provided that includes a manifold, at least one injection nozzle coupled to the manifold, an actuator, and a valve pin adapted to reciprocate through the manifold manifold and the injection nozzle. The valve pin has a first end coupled to the actuator, a second end that closes the gate in a forward position, and a control surface intermediate said first and second ends for adjusting the rate of material flow during an injection cycle. Retracting the valve pin tends to decrease the rate of material flow during the injection cycle and displacing the valve pin toward the gate tends to increase the rate of material flow during the injection cycle.
Abstract:
An injection molding apparatus and method are provided in which the rate of material flow during an injection cycle is controlled. According to one preferred embodiment, an injection molding apparatus is provided that includes a manifold, at least one injection nozzle coupled to the manifold, an actuator, and a valve pin adapted to reciprocate through the manifold and the injection nozzle. The valve pin has a first end coupled to the actuator, a second end that closes the gate in a forward position, and a control surface intermediate said first and second ends for adjusting the rate of material flow during an injection cycle. Retracting the valve pin tends to decrease the rate of material flow during the injection cycle and displacing the valve pin toward the gate tends to increase the rate of material flow during the injection cycle.