Abstract: An injection molding apparatus for small pitch molding includes a plurality of mold cavities having a small pitch therebetween. The injection molding apparatus includes a manifold for delivering melt to a sub-manifold. The sub-manifold including at least one upstream manifold plate and a downstream nozzle plate. The upstream manifold plate and/or the nozzle plate includes a heater. At least one unheated nozzle is mounted in the downstream nozzle plate for receiving melt from the sub-manifold and delivering the melt to a mold cavity.

Abstract: A stack or tandem injection molding apparatus includes a first melt transfer nozzle coupled to a stationary platen and a second melt transfer nozzle coupled to a movable platen. A melt transfer device includes a first valve pin extending through a first melt transfer channel of the first melt transfer nozzle and a second valve pin extending through a second melt transfer channel of the second melt transfer nozzle. At least one groove is provided in the outer surface of the first valve pin. The first valve pin is movable relative to the first and second melt transfer nozzles to selectively locate the groove across a portion of the first melt transfer channel and a portion of the second melt transfer channel to allow melt to flow therebetween in the mold closed position and to prevent drooling in the mold open position.

Abstract: A nozzle for an injection molding apparatus is provided. The injection molding apparatus has a mold component that defines a mold cavity and a gate into the mold cavity. The nozzle includes a nozzle body, a heater, a tip, a tip surrounding piece and a mold component contacting piece. The nozzle body defines a nozzle body melt passage therethrough, that is adapted to receive melt from a melt source. The heater is thermally connected to the nozzle body for heating melt in the nozzle body. The tip defines a tip melt passage therethrough, that is downstream from the nozzle body melt passage, and that is adapted to be upstream from the gate. The tip surrounding piece is removably connected with respect to said nozzle body. The mold component contacting piece is connected with respect to the nozzle body.

Abstract: A nozzle for an injection molding apparatus is provided. The nozzle includes a nozzle body, a heater and an insert. The nozzle body defines a first melt channel therein. The first melt channel is adapted to be downstream from and in fluid communication with a melt source. The nozzle body has a downstream nozzle body end. The nozzle body is made from a nozzle body material. The heater is thermally connected to the nozzle body. The insert is positioned in the nozzle body. The insert is made of an insert material. The insert material is more thermally conductive than the nozzle body material. The insert is adapted to conduct heat from the heater towards the downstream nozzle body end.

Abstract: A nozzle for an injection molding apparatus is provided. The nozzle includes a nozzle body, a heater and a first gap seal surface. The nozzle body defines a nozzle body melt passage, that is adapted to be downstream from and in fluid communication with a melt source, and upstream from and in fluid communication with a gate into a mold cavity in a mold component. The heater is thermally connected to the nozzle body for heating melt in the nozzle body melt passage. The first gap seal surface is positioned on a structure that is connected at least indirectly to the nozzle body. The first gap seal surface is adapted to be separated by a gap with respect to a second gap seal surface on the mold component. The gap is sized to inhibit the flow of melt between the first gap seal surface and the second gap seal surface.

Abstract: A nozzle for an injection molding apparatus is provided. The injection molding apparatus has a mold component that defines a mold cavity and a gate into the mold cavity. The nozzle includes a nozzle body, a heater, a tip, a tip surrounding piece and a mold component contacting piece. The nozzle body defines a nozzle body melt passage therethrough, that is adapted to receive melt from a melt source. The heater is thermally connected to the nozzle body for heating melt in the nozzle body. The tip defines a tip melt passage therethrough, that is downstream from the nozzle body melt passage, and that is adapted to be upstream from the gate. The tip surrounding piece is removably connected with respect to said nozzle body. The mold component contacting piece is connected with respect to the nozzle body.

Abstract: A valve pin guide is provided for guiding a valve pin from a nozzle into a gate of a mold cavity in an injection molding apparatus. The valve pin guide defines a guide aperture therethrough. The guide aperture is adapted to receive and guide the valve pin into alignment with the gate. The valve pin guide is positioned downstream from said nozzle and upstream from said gate.

Abstract: A seal is provided between a nozzle and a manifold. The seal provides a melt channel between an outlet of the manifold and a nozzle channel. The seal has higher thermal expansion coefficient than both the nozzle and the manifold to provide an improved seal between the manifold and the nozzle when the injection molding apparatus is at an operating temperature.

Abstract: An apparatus and method for injection molding of molded products including a first cavity chamber for forming a seal liner, with the first cavity chamber having an outer edge, and a second cavity chamber for forming a shell, with the second cavity chamber having a center and being adjacent to the first cavity chamber. The injection molding apparatus and method also includes a first nozzle for a seal liner material positioned near the outer edge of, and in communication with, the first cavity chamber, and a second nozzle for a shell material positioned near the center of, and in communication with, the second cavity chamber. The injection molding apparatus and method further includes a mold core capable of being positioned in and moved between the first and second cavity chambers.

Abstract: A valve pin actuating mechanism including a valve pin guiding element for connection to a valve pin, a linkage element and an actuator. The valve pin guiding element has a sliding surface for sliding within a channel, and first and second engagement surfaces. The linkage element has first and second arms, which have opposing, inwardly facing arcuate engagement surfaces for engaging the valve pin guiding element. The linkage element is moved by the actuator.

Abstract: A collar for a hot runner nozzle of an injection molding apparatus includes a generally cylindrical body having a first flange extending inwardly from a first end thereof. The first flange is provided to abut a nozzle head and at least a portion of a nozzle body of a nozzle. An alignment flange projects from an inner wall of the generally cylindrical body and is spaced from the first flange. The alignment flange contacts the nozzle body to restrict tipping of the collar relative to the nozzle during assembly of the injection molding apparatus.

Abstract: Post-mold cooling of injection molded plastic articles such as preforms is achieved by transferring the articles directly from the mold cavities onto cooling cores carried by a take-out plate. The molded articles are supported on the cooling cores until they become sufficiently frozen that they can be stripped from the cores.

Abstract: An injection molding apparatus includes an injection piston that is slidable within a nozzle having a movable valve gate pin. The injection piston is movable from a retracted position to an extended position in order to force melt towards a mold cavity. A valve is located at a forward end of the piston to selectively block communication between a recess, which is provided in an outer wall of the piston adjacent the valve, and a melt chamber of the nozzle. Movement of the injection piston from the retracted position to the extended position causes the valve to close so that the predetermined volume of melt located below the valve is forced into the mold cavity, when the valve gate pin opens the mold gate.

Abstract: A nozzle for an injection molding apparatus is provided. The nozzle includes a nozzle body, a heater and a first gap seal surface. The nozzle body defines a nozzle body melt passage, that is adapted to be downstream from and in fluid communication with a melt source, and upstream from and in fluid communication with a gate into a mold cavity in a mold component. The heater is thermally connected to the nozzle body for heating melt in the nozzle body melt passage. The first gap seal surface is positioned on a structure that is connected at least indirectly to the nozzle body. The first gap seal surface is adapted to be separated by a gap with respect to a second gap seal surface on the mold component. The gap is sized to inhibit the flow of melt between the first gap seal surface and the second gap seal surface.

Abstract: An injection molding apparatus comprises a manifold having a manifold channel for receiving a melt stream of moldable material under pressure and delivering the melt stream to a nozzle channel of a nozzle. A mold cavity is in communication with the nozzle channel of the nozzle and receives melt through a mold gate. A valve pin is axially movable through the nozzle channel of the nozzle to selectively open the mold gate. The mold gate is open when the valve pin is in an extended position and a portion of the valve pin is received in the mold cavity. At least one groove is provided in an outer surface of the valve pin and at least a portion of the outer surface of the valve pin is in continuous engagement with the mold gate to align the valve pin relative to the mold gate. When the valve pin is in the extended position, the groove is aligned with the mold gate to allow melt to flow between the nozzle channel and the mold cavity.

Abstract: A seal is provided between a nozzle and a manifold. The seal provides a melt channel between an outlet of the manifold and a nozzle channel. The seal has higher thermal expansion coefficient than both the nozzle and the manifold to provide an improved seal between the manifold and the nozzle when the injection molding apparatus is at an operating temperature.

Abstract: An improved melt distribution system and method is provided for a multi-level stack mold having three or more moving platens. The injection machine communicates with a bifurcated sprue bar for providing pressurized melt through the first moving platen to a central distribution manifold in the second moving platen. From the central distribution manifold, the flow of pressurized melt is distributed to the first and third platens for transfer to a plurality of mold cavities.

Abstract: A valve bushing assembly for use in an injection molding apparatus is provided. The injection molding apparatus includes a manifold block, a valve pin, and an actuator block. The manifold block has at least one melt channel therein. The manifold block has an exterior surface that faces the actuator block, and has a manifold pass-through extending from the exterior surface to the at least one melt channel. The manifold pass-through has a manifold sealing surface therein. The manifold pass-through permits the valve pin to pass therethrough. The actuator block has an actuator attached thereto, that is operatively connected to the valve pin. The valve bushing assembly includes a bushing and a spacer. The bushing is adapted to be received in the manifold pass-through. The bushing has a bushing pass-through that is adapted to align with the manifold pass-through and is adapted to slidably receive the valve pin.

Abstract: An injection molding apparatus comprises a first sprue bar element having a first sprue channel for receiving a melt stream of moldable material under pressure. A second sprue bar element has a second sprue channel for selectively receiving the melt stream from the first sprue channel. A manifold has a manifold channel for receiving the melt stream from the second sprue channel and delivering the melt stream to a nozzle channel of a nozzle. A mold cavity receives the melt stream from the nozzle. The nozzle channel communicates with the mold cavity through a mold gate. A first gate assembly is coupled to an outlet of the first sprue bar element for selectively restricting the flow of the melt stream from the first sprue channel. The first gate assembly is movable to restrict the flow when the flow of the melt stream between the first sprue channel and the second sprue channel is interrupted.

Abstract: A heater assembly for an injection molding apparatus comprises a heater sleeve having a threaded inner surface for engaging a threaded outer surface of a nozzle body of a nozzle or a threaded surface of a mold manifold. A clamping element such as a lock nut or a spring is provided adjacent the heater sleeve. The lock nut and/or the spring abuts the heater sleeve to force the threaded inner surface of the heater sleeve into contact with the threaded outer surface of the nozzle body. This removable clamped heater assembly operates regardless of the temperature of heater.