Abstract: An injection molding hot runner apparatus and insert assembly for use in a manifold of the apparatus. The apparatus includes a mold manifold, a cylindrical insert for redirecting melt within the mold manifold, and an expandable sleeve surrounding the insert. When the manifold, insert and sleeve are heated to an operational temperature (e.g. 300° C.), the sleeve expands to create a fluid tight seal between the manifold and the insert. The insert assembly including the insert and sleeve is mountable in the mold manifold to redirect melt.

Abstract: The present invention provides an electrically heated nozzle for injection molding which is insulated to prevent conduction of electricity and loss of thermal transmission to the casing, wherein at least a part of the electrical insulation comprises a layer of dielectric insulator material with an electrical resistance wire wound spirally thereabout and another dielectric insulator layer thereover. Also disclosed is a method for making such a nozzle which includes the steps of applying a first insulator layer, winding electrical resistance wire about the first insulator layer, applying a second insulator layer, and applying a casing layer thereover. The first and second insulating layers may be provided by spraying or through telescoping, self-supporting sleeves.

Abstract: An anti-drool mechanism suitable for use in an injection molding system is provided herein. An injection molding machine includes a retractable machine nozzle for injecting a melt stream into a manifold. Between the machine nozzle and the manifold is an anti-drool mechanism, which includes a melt passage and a fixed pin disposed within the melt passage. The fixed pin is sized so that the melt stream will flow around the pin. The fixed pin has a head portion configured to engage with the machine nozzle and includes a first sealing surface. An actuated shut-off collar is also disposed within the melt passage, surrounding the pin, and includes a second sealing surface configured to cut off the flow of the melt stream when in contact with the first sealing surface.

Abstract: The present invention provides an electrically heated nozzle for injection molding which is insulated to prevent conduction of electricity and loss of thermal transmission to the casing, wherein at least a part of the electrical insulation comprises a layer of dielectric insulator material with an electrical resistance wire wound spirally thereabout and another dielectric insulator layer thereover. Also disclosed is a method for making such a nozzle which includes the steps of applying a first insulator layer, winding electrical resistance wire about the first insulator layer, applying a second insulator layer, and applying a casing layer thereover. The first and second insulating layers may be provided by spraying or through telescoping, self-supporting sleeves.

Abstract: An edge gated injection molding apparatus includes a manifold having a manifold channel for receiving a melt stream of moldable material under pressure. A nozzle is coupled to the manifold and a nozzle melt channel of the nozzle receives the melt stream from the manifold channel. A mold cavity communicates with the nozzle melt channel of the nozzle and receives melt through a mold gate. The mold gate is located at an edge of the mold cavity. A chamber receives melt from the nozzle channel and communicates with the mold cavity through the mold gate. A portion of the chamber is located forward of the mold gate. A valve pin is slidable through the nozzle channel from a first position in which the mold gate is open to a second position in which an outer side surface of the valve pin blocks the mold gate.

Abstract: An injection molding apparatus includes a manifold for delivering a melt stream of moldable material to a nozzle melt channel of a nozzle. A valve pin extends through the nozzle melt channel and is axially movable to selectively open a gate to allow communication with a mold cavity. A sensor is coupled to a forward end of the valve pin. The sensor may be a pressure sensor and/or temperature sensor in direct contact with the melt stream to provide pressure and/or temperature information to a controller.

Abstract: An injection molding apparatus includes a manifold having a manifold channel for receiving a melt stream from a source. A nozzle having a nozzle channel receives the melt stream from the manifold channel and delivers the melt stream to a mold cavity through a mold gate. A valve pin bushing is provided between the manifold and the nozzle and includes a bore for receiving a valve pin. A chamber is provided in said valve pin bushing and communicates with the bore. An inlet channel extends between an inlet, which is located in an outer surface of the valve pin bushing, and the chamber. A vent channel extends between the chamber and an outlet, which is located in the outer surface of the valve pin bushing. A forced fluid source communicates with the inlet channel to force fluid through the inlet channel, said chamber and the vent channel.

Abstract: An injection molding apparatus is disclosed that includes a manifold having at least one manifold melt channel therethrough, a mold plate defining a gate for transmitting melt flow to a mold cavity, and at least one nozzle including a nozzle body and nozzle tip defining a nozzle melt channel in communication with the manifold melt channel. The nozzle tip includes a substantially conical forward portion having a terminal end that is aligned with and spatially offset a predetermined distance “d” from the gate, the nozzle melt channel having a discharge opening that is located rearward of the terminal end for discharging melt flow from the nozzle melt channel towards the gate.

Abstract: A nozzle sealing assembly includes a cup-shaped nozzle seal cap and a sealing ring. The nozzle seal cap is coupled to a nozzle body and surrounds a tip portion of the nozzle body. The sealing ring is coupled to an outer surface of the nozzle seal cap and provides a sealing surface that is configured to slidably contact an adjacent mold plate.

Abstract: A nozzle for an injection molding apparatus, including a nozzle body having a nozzle melt channel for receiving a melt stream from a manifold melt channel, and a collar mounted on the nozzle body. One of the nozzle body and the collar has a shoulder formed therein and the other of the nozzle body and collar has a radially disposed protrusion for engaging the shoulder to act against separation of the collar from the nozzle body.

Abstract: An injection molding hot runner nozzle includes a nozzle body comprising a nozzle core, a nozzle tip, and a melt passage extending through the nozzle body for conveying melt from a manifold through the nozzle tip and to a gate of a mold cavity. A cylindrical sleeve is disposed around the nozzle body, the sleeve being slidably removable from the nozzle body. A wire heating element for heating melt in the melt passage is is spirally wound about the sleeve. A temperature sensor comprising a wire is spirally wound about the sleeve.

Abstract: An injection molding apparatus including an injection manifold having a manifold melt channel, a mold plate having a mold bore, and a hot runner nozzle located in the mold bore and having a nozzle melt channel. A mold insert including a melt channel includes an upper end adjacent the nozzle, a first outer surface adjacent the upper end, and a lower portion including a second outer surface, wherein the second outer surface is in sealing contact with an inner surface of the mold plate. A mold gate insert retainer includes an inner surface surrounding the first outer surface of the mold gate insert and a threaded outer surface for mating with a threaded inner surface of the nozzle. The first outer surface of the mold gate insert and the inner surface of the mold gate insert retainer are non-threaded. A lower end surface of the mold gate insert may form a wall of the mold cavity and may be angled.

Abstract: A valve-gated nozzle in an injection molding machine allows for smooth, blended melt flow into a mold cavity. In one example, this is accomplished through use of a valve-gated nozzle having a nozzle body with a nozzle melt channel in fluid communication with a manifold melt channel and a nozzle tip. The nozzle tip includes a first melt channel in fluid communication with the nozzle melt channel and a plurality of release melt channels between the first melt channel and an annular melt channel. The annular melt channel is formed between a retaining device and the nozzle tip. The annular melt channel includes a decompression chamber in fluid communication with respective ones of the release melt channels and a compression chamber between the decompression chamber and a mold.

Abstract: An injection molding apparatus includes a manifold having a manifold channel for receiving a melt stream of moldable material from a source and delivering the melt stream to a nozzle channel of a nozzle. A mold cavity communicates with the nozzle channel to receive the melt stream through the mold gate. A distribution assembly is located adjacent to the manifold. The distribution assembly includes at least one distribution member including a first conduit and a second conduit extending therethrough for transporting a fluid from a source through the distribution assembly and for returning the fluid to the source. A valve box is sandwiched between the distribution member and the actuator. The valve box controls the flow of the fluid between the first and second conduits and the actuator.

Abstract: A nozzle in an injection molding machine allows for smooth, blended melt flow into a mold cavity. In one example, this is accomplished through use of a nozzle having a nozzle body with a nozzle melt channel in fluid communication with a manifold melt channel and a nozzle tip. The nozzle tip includes a first melt channel in fluid communication with the nozzle melt channel and a plurality of release melt channels between the first melt channel and an annular melt channel. The annular melt channel is formed between a retaining device and the nozzle tip. The annular melt channel includes a decompression chamber in fluid communication with respective ones of the release melt channels and a compression chamber between the decompression chamber and a mold. A pressure difference formed between the respective release melt channels and the decompression chamber and between the decompression chamber and the compression chamber blends the molten material to even and balance flow into the mold cavity.

Abstract: An injection molding apparatus includes a manifold having a manifold channel for receiving a melt stream of moldable material from a source and delivering the melt stream to a nozzle channel of a nozzle. A mold cavity communicates with the nozzle channel to receive the melt stream through the mold gate. A distribution assembly is located adjacent to the manifold. The distribution assembly includes at least one distribution member having a groove formed in an outer surface thereof and at least one conduit provided in the distribution member. The groove receives wiring from a heater of the nozzle and routes the wiring to a termination location or box. The conduit distributed fluid to various locations in the injection molding apparatus, such as actuation fluid for an actuator.

Abstract: An injection molding apparatus includes 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. The manifold includes a manifold plug fit within a bore thereof and having a plug melt channel for fluidly connecting the manifold melt channel and the nozzle melt channel. The manifold plug further includes a valve/pressure disk portion that abuts with a back plate of the injection molding apparatus to maintain the spacing therebetween and to accommodate thermal expansion of the manifold relative to the back plate. In an injection molding application utilizing a valve-gated nozzle, the manifold plug may further include a valve pin receiving/guiding bore that functions as a valve pin bushing for a valve pin. A mold cavity communicates with the nozzle channel of the nozzle to receive melt through a mold gate.

Abstract: A method and apparatus for rotating a cross-sectional asymmetrical condition of a laminar flowing material is provided in a hot runner system for supplying a laminar flowing material. The hot runner system has (i) an upstream melt passage, (ii) a pair of intermediary melt passages downstream from the upstream melt passage, and (iii) for at least one intermediary melt passage, an associated pair of downstream melt passages downstream from the at least one intermediary melt passage. The cross-sectional asymmetrical condition of a laminar flowing material is rotated by providing a bending path for orienting at least one path outlet relative to a path inlet to rotate the cross-sectional asymmetrical condition of the laminar flowing material such that the cross-sectional asymmetrical condition is substantially equally divided between the two downstream portions.

Abstract: A collar for an injection molding apparatus includes an upstream end for maintaining a head of a hot runner nozzle in contact with an outlet surface of a manifold and a downstream end for abutting a mold plate. An inner surface of the collar contacts an outer surface of the nozzle in order to align a nozzle channel of the nozzle with a manifold channel outlet of the manifold. A noncircular ridge protrudes from the inner surface of the collar in order to reduce contact between the outer surface of the nozzle and the collar.

Abstract: A valve pin for use in a melt channel in an injection molding machine. The valve pin has a valve pin body and at least one thermocouple substantially completely inside the valve pin body.