Abstract: The invention relates to an adjustment device for a valve pin on an injection molding machine, and particularly on a multi-cavity machine, having a plurality of valve pins mounted on a common yoke plate which is actuated by a common actuator. The adjustment device includes a pin holder for holding the valve pin, and a locking member. The pin holder has two threaded portions. The first threaded portion is adjustable within a threaded receiving hole in the yoke plate. The second threaded portion is received by the locking member. The locking member has a bottom shoulder which butts against the yoke plate, and retains the pin holder in place.

Abstract: A nozzle end is provided for removable mounting to a nozzle body for use in multiple-tipped molding applications such as edge-gated systems. The nozzle end is made of a highly thermally conductive material and is preferably inserted at least partially inside the forward end of the heated nozzle body. Removable nozzle tips are insertable in the front end of the nozzle end.

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.

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: 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, with first and second electric heaters which can operate independently or simultaneously to heat the melt channel of the nozzle.

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, with first and second thermocouples for sensing temperature of the nozzle, the two thermocouples are independent so they can act either independently or simultaneously to sense temperature conditions in the melt channel of the nozzle.

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: An injection nozzle for an injection molding apparatus is provided. The injection nozzle includes a head portion, a body portion and a heater. The head and body portions are connected to each other and together define a nozzle melt channel. The head portion has a head portion outer surface. The head portion is adapted to be in contact with a molding apparatus component that is at a lower temperature than the head portion. The body portion has a body portion outer surface. A groove is defined in the head portion outer surface and the body portion outer surface. The heater wire is positioned in the groove. The heater is adapted to heat melt in the nozzle melt channel.

Abstract: A guide for a manifold plug of an injection molding apparatus comprises a guide body projecting from an inner wall of the manifold plug diametrically opposing an inlet of a manifold plug channel formed in the manifold plug. The inlet is aligned with a manifold channel of a manifold. The outlet of the manifold plug channel is aligned with a nozzle channel of a nozzle. The inlet is at an angle to the outlet. A guide surface is provided on the guide body for abutting a downstream portion of a valve pin extending into the manifold plug channel. The guide also facilitates flow of a melt stream of moldable material through the manifold plug channel.

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: 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, with first and second electric heaters which can operate independently or simultaneously to heat the melt channel of the nozzle.

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: 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 system is provided for an injection molding machine. The nozzle system includes a nozzle tip that is removably connected to a nozzle body with a sealing and mounting sleeve element. The nozzle body includes a first connector for releasably connecting with a second connector defined on the sleeve. The sleeve element further includes an alignment bearing for engaging a bearing surface defined on the nozzle body for precisely locating the nozzle tip within the nozzle body along on a predetermined axis. Further embodiments of the invention provide a valve pin disposed in the nozzle body and nozzle tip. The valve pin includes a bearing surface for engaging a guiding surface defined on the second melt channel for aligning the end of the valve pin with a mold gate. Further embodiments also provide an integrally connected nozzle tip and sleeve element.

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 nozzle end is provided for removable mounting to a nozzle body for use in multiple-tipped molding applications such as edge-gated systems. The nozzle end is made of a highly thermally conductive material and is preferably inserted at least partially inside the forward end of the heated nozzle body. Removable nozzle tips are insertable in the front end of the nozzle end.

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: 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, with first and second thermocouples for sensing temperature of the nozzle, the two thermocouples are independent so they can act either independently or simultaneously to sense temperature conditions in the melt channel of the nozzle.

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, with first and second electric heaters which can operate independently or simultaneously to heat the melt channel of the nozzle.

Abstract: A valve pin assembly for an injection molding apparatus comprising a valve pin capable of movement up and down in a nozzle to open and close a ring gate. An annular passage is created through the nozzle and is unobstructed and without restriction at all points up to and through the ring gate, permitting melt to flow freely to the gate and, depending on the position of the valve pin, into the mold cavity. The valve pin has a head with a diameter larger than the valve pin shaft for selectively closing the gate. The ring gate channel diameter is larger than the melt channel diameter to permit parts with large apertures therein to be formed.