Abstract: Method for sealing interfaces within an injection mold having a first surface and a second surface includes structure and/or steps whereby an active material actuator configured to be disposed in a manner suitable for generating a force between the first surface and the second surface. The active material actuator is configured to generate a force in response to sense signals from a transmission structure. Methods are also provided for centering a nozzle tip within a gate opening, and adjusting tip height of a nozzle tip with respect to a gate opening, also using active material inserts.

Abstract: A manifold system (50) comprising a main manifold (56) with a plurality of arms (64), a plurality of sub-manifolds (52) spaced from the main manifold (56) and communicating with the main manifold (56) through a plurality of melt transfer bushings (68) disposed between the main manifold (56) and the sub-manifolds (52). The melt transfer bushings (68) may include static mixers (140) to homogenize the melt. An air plate (70) is disposed between a backing plate (58) preferably housing the main manifold (56) and a manifold plate (54) preferably housing the sub-manifolds (52). The air plate (70) has a plurality of air channels (74) that communicate with valve gate nozzle actuators (90), which are received in actuator cavities (72) in the air plate (70). The air plate (70) is bolted to the manifold plate (54), and the backing plate (58) is bolted to the air plate (70) with bolting patterns not constrained by location of the main manifold (56) or sub-manifolds (52). The manifold system (50), as shown in FIG.

Abstract: Method and apparatus are provided for sealing interfaces within an injection mold having a first surface and a second surface includes an active material actuator configured to be disposed in a manner suitable for generating a force between the first surface and the second surface. The active material actuator is configured to generate a force in response to sense signals from a transmission structure. Methods and apparatus are also provided for centering a nozzle tip within a gate opening, and adjusting tip height of a nozzle tip with respect to a gate opening, also using active material inserts.

Abstract: Improved hot runner valve gate piston apparatus and method includes structure and steps whereby the air piston cylinder wall transmits less than all of the compressive force between the backplate and the manifold. Preferably, a backup pad is disposed in contact with the manifold and the backplate, for transmitting some of these compressive forces. Preferably, the backup pad also transmits heat from the backplate to the manifold, reducing the temperature of the cylinder wall. A flex member is preferably provided adjacent to or integral with the cylinder for absorbing some of the compressive forces between the backplate and the manifold, and in order to maintain the air seal between the piston cylinder in the air channel in the hot runner backplate.

Abstract: An injection molding nozzle tip insulator includes an inner annular portion in contact with the injection molding nozzle tip, and an outer annular portion in contact with the inner annular portion, the outer annular portion being less thermally conductive than the inner annular portion so that the insulator has a stepped heat gradient profile from an inside to an outside thereof.

Abstract: Improved hot runner valve gate piston apparatus and method includes structure and steps whereby the air piston cylinder wall transmits less than all of the compressive force between the backplate and the manifold. Preferably, a backup pad is disposed in contact with the manifold and the backplate, for transmitting some of these compressive forces. Preferably, the backup pad also transmits heat from the backplate to the manifold, reducing the temperature of the cylinder wall. A flex member is preferably provided adjacent to or integral with the cylinder for absorbing some of the compressive forces between the backplate and the manifold, and in order to maintain the air seal between the piston cylinder in the air channel in the hot runner backplate.

Abstract: Improved hot runner valve gate piston apparatus and method includes structure and steps whereby the air piston cylinder wall transmits less than all of the compressive force between the backplate and the manifold. Preferably, a backup pad is disposed in contact with the manifold and the backplate, for transmitting some of these compressive forces. Preferably, the backup pad also transmits heat from the backplate to the manifold, reducing the temperature of the cylinder wall. A flex member is preferably provided adjacent to or integral with the cylinder for absorbing some of the compressive forces between the backplate and the manifold, and in order to maintain the air seal between the piston cylinder in the air channel in the hot runner backplate.

Abstract: An injection molding nozzle tip insulator includes an inner annular portion in contact with the injection molding nozzle tip, and an outer annular portion in contact with the inner annular portion, the outer annular portion being less thermally conductive than the inner annular portion so that the insulator has a stepped heat gradient profile from an inside to an outside thereof.

Abstract: An injection molding nozzle tip thermal insulator includes an apparatus for removably fastening the insulator to a nozzle tip having a receiving detent therein. The apparatus includes a fastening structure that engages the nozzle tip receiving detent and holds the insulator onto the nozzle tip. The fastening structure is movable between a first position where the insulator is fastened to the nozzle tip, and a second position where the insulator is removable from the nozzle tip. Also included are a method of removably attaching the insulator to the nozzle tip, and assembly and removal tools for attaching and removing the insulator from the nozzle tip, respectively.

Abstract: An apparatus and process for injecting molten plastic material includes a nozzle assembly through which plastic material flows and including a nozzle body with a heater affixed thereto. A mold cavity plate is positioned adjacent the nozzle body and is separable from the nozzle body so that separation of the mold cavity plate from the nozzle body exposes the nozzle body and permits removal of the nozzle body and the heater.

Abstract: A novel valve gated injection molding system and valve gate reduces the formation of gate vestiges on parts molded therewith and enhances cooling of the tip of the valve stem during the cooling portion of an injection molding cycle. Channels are provided and extend from an area adjacent the contact area of the sealing portions of the stem tip and gate to the melt channel of the injection nozzle. These channels allow material, which would otherwise form a thin film layer in the contact area of the sealing portions of the stem tip and gate, to be expressed through the channels and back to the injection nozzle. As the formation of thin films is inhibited, an increased contact area, in addition to the contact area of the tip and gate sealing portions, can be provided to improve the transfer of heat energy from the tip to the gate when the gate is cooled.

Abstract: The foregoing objects are attained by the opposed gating injection method and apparatus for forming molded articles and for use with injection molders wherein a first mold half and a second mold half are adapted to cooperate and form at least one mold cavity. A first injector nozzle is positioned in a first mold half adjacent the cavity, for injecting a first molding resin into the cavity through a first orifice. A second injector nozzle is included which is positioned in the second mold half adjacent the cavity for injecting a second molding resin. The second resin may be different from the first resin or the same as the first resin. The second resin is injected through a second orifice unconnected with the first orifice. The injector nozzles may be either simultaneously or sequentially activated for filling the mold cavity, and may be single material or co-injection type nozzles.

Abstract: The foregoing objects are attained by the inventive opposed gating injection method and apparatus of the instant invention for forming molded articles and for use with injection molders wherein a first mold half and a second mold half are adapted to cooperate and form at least one mold cavity. The invention includes a first injector nozzle positioned in a first mold half adjacent the cavity, for injecting a first molding resin into the cavity through a first orifice. A second injector nozzle is included which is positioned in the second mold half adjacent the cavity for injecting a second molding resin. The second resin may be different from the first resin or the same as the first resin. The second resin is injected through a second orifice unconnected with the first orifice. In accordance with the invention, the injector nozzles may be either simultaneously or sequentially activated for filling the mold cavity, and may be single material or co-injection type nozzles.

Abstract: The foregoing objects are attained by the inventive opposed gating injection method and apparatus of the instant invention for forming molded articles and for use with injection molders wherein a first mold half and a second mold half are adapted to cooperate and form at least one mold cavity. The invention includes a first injector nozzle positioned in a first mold half adjacent the cavity, for injecting a first molding resin into the cavity through a first orifice. A second injector nozzle is included which is positioned in the second mold half adjacent the cavity for injecting a second molding resin. The second resin may be different from the first resin or the same as the first resin. The second resin is injected through a second orifice unconnected with the first orifice. In accordance with the invention, the injector nozzles may be either simultaneously or sequentially activated for filling the mold cavity, and may be single material or co-injection type nozzles.

Abstract: An injection molding heater system for heating molding resins or plastics includes a plurality of heaters for heating resin wherein each of the heaters is positioned adjacent a nozzle or manifold. The system also includes an electrical circuit which is connected with the heaters and carries electricity from a power source to each of the heaters in order to energize the heaters. A plurality of circuit breaking devices are incorporated in the circuit for discontinuing the flow of electricity through each of the electrical circuits for preventing circuit damage in case of overcurrent, surges or the like. At least one circuit breaker is positioned in each of the electrical circuits between the power source and each of the heaters.

Abstract: The present invention relates to an improved nozzle-manifold assembly having utility in injection molding machines for making molded plastic articles. The nozzle assembly employs a clamp ring to apply a clamping force to the nozzle housing to cause it to mate with a manifold so as to prevent leakage of molten plastic material between the nozzle housing and the manifold. The clamp ring is mounted to the manifold by a plurality of screws whose tightening creates the desired clamping force and an effective seal between the nozzle housing and the manifold. The nozzle-manifold assembly also includes a centering ring for positioning the nozzle housing within a bore in a mold plate.

Abstract: A rotary actuated gate valve for directing melt from a channel in a manifold to a mold gate includes a valve stem extending through and rotatable within the manifold. The valve stem includes a groove in fluid communication with the channel, wherein the groove is adapted to be rotated into alignment with the mold gate and channel for allowing the melt to flow into the mold gate. The groove is also adapted to be rotated out of alignment with the mold gate and channel for blocking the melt from flowing into the mold gate. The gate valve also includes a mechanism for rotating the valve stem. Another embodiment includes a rotatable housing having a groove, which operates in a manner similar to the valve stem design.