Abstract: A mold assembly for casting or molding a multiple portion article in sequential shots without opening the mold assembly. The mold assembly includes a movable mold insert that permits the portions to be interconnected as an integral part of the casting process. The mold insert includes a first or male void for defining a male end and a second or female void for defining a female end. In operation, the mold insert is placed in a first position and molten material is introduced into a first cavity portion to form a first portion with a male end. The mold insert is then placed in a second position with the female portion surrounding the male end of the first portion. Molten material is introduced into a second cavity portion to form a second portion with a female end at least partially surrounding the male end of the first portion.

Abstract: A mold for molding a semiconductor package which is capable of guiding a resin material for encapsulating a semiconductor device uniformly into the cavity and prevents the island portion of the support member from being exposed from the molding main body, the mold comprising a pair of mold members for encapsulating a semiconductor device held on the support member, and a gate for guiding a molding resin material into the cavity, the gate being provided in the parting face of parting face of at least one of the mold members, wherein the gate is defined by a U-shape groove including the slanted bottom face inclined at an elevation angle toward the cavity to orient the flow of the resin material, supplied to the gate, toward the half of the cavity defined by the other mold member from the gate, and wherein in the slanted bottom face, there is provided an auxiliary groove for making the resin material, generally guided along the slanted bottom face, partially oriented to a direction different from the direction o

Abstract: A method and apparatus for forming stackable plastic battery containers having stacking grooves is disclosed. A hot tip injection nozzle is centrally located within a raised section of a die thereby forming a depression within the stacking grooves. The nozzle has a gate offset from the nozzle center line. In this manner, the gate remnant formed by the gate offset does not interfere with the stacking of the containers.

Abstract: A composite insulator-producing lateral type molding apparatus includes a mold body constituted by a first molding unit and a second molding unit, each of said first and second molding units being provided, at an inner peripheral face, with recesses for the formation of a housing constituted by a plurality of shed portions and a axial portion connecting these shed portions, means for opening or tightening the first molding unit and the second molding unit, a pouring passage for pouring a housing-forming material into said recesses, and housing-forming material escape holes. A core member of the insulator is placed between the first and second molding units, the first and second molds are tightened, and the housing-forming material is poured into said recesses to form the housing. The first molding unit and the second molding unit extend laterally, and that the core member is laterally arranged horizontally between first and second molding units.

Abstract: A molding apparatus includes a movable mold-defining member mounted on the movable side of an injection machine and a stationary mold-defining member mounted on its stationary side. Those members are joinable to define a mold cavity and a runner channel therebetween. The movable mold-defining member is provided with a dividing member for dividing the runner channel, or cavity, or both into a plurality of portions. The dividing member is normally urged by an elastic member to project into the channel, or cavity. The dividing member has one side which is substantially perpendicular to the direction of flow of a molding resin material to stop its flow past the dividing member, and an opposite side cut away partly to form a recess at one end thereof, so that another molding resin material reaching the opposite side may flow into the recess and thereby move said dividing member out of the channel, or cavity by overcoming the force of the elastic member.

Abstract: A process and an apparatus (10) for the production of a plastic article of large area and small wall thickness, wherein the plastic material (90) is injected in the viscous condition into a mold cavity which is defined by a bottom mold portion (20) and a top mold portion (36). During the operation of injection of the viscous plastic material, which takes place through an inlet (76), the top mold portion (36), with the bottom mold portion (20), forms a pre-molding cavity (86) which is enlarged in a wedge shape starting from the inlet (76). During injection of the viscous plastic material (90) into the pre-molding cavity (86) or immediately after the injection operation, the bottom and top mold portions (20, 36) are moved relatively towards each other, forming the definitive mold cavity (78), so that the viscous plastic material is uniformly distributed in the diminishing mold cavity.

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: Apparatus for pulsating gas-assisted injection molding hollow tubular plastic parts includes the injection of a molten plastic into a mold cavity in an amount less than the cavity volume and in separate molten plastic flows that flow along the cavity and ultimately unite in a solidifying fusion welding state at an interface. A pressurized gas is injected into the molten plastic to form a central void in the molten plastic extending to opposite sides of the interface leaving a voidless solidifying fusion weld section encompassing the interface. The gas pressure acting on the opposite sides of the interface is trapped and then alternately increased and decreased by a separate gas injection that creates gas pulsations that effect shifting of the molten weld section in opposite directions to force intermingling of the plastic molecules therein and across the interface to enhance the strength of the fusion weld section on solidification and eliminate appearance knit lines.

Abstract: An injection molding apparatus for a resin structure uses gas injection. The apparatus includes a resin supply that feeds more than one resin to a mold, a gas exhaust that discharges gas supplied to the resin in order to closely contact the resin to the mold, and a supply selector that selectively opens and closes the resin supply using the pressure of the discharged gas to supply a different kind of resin onto the inner surface of a previously supplied resin.

Abstract: The plastic substrate portion of the part is formed by a first injection of plastic into a mold, so as to adhere to an overlying sheet of coverstock material. A portion of the coverstock is not initially adhered to the substrate. A second injection of plastic forms the undecorated portion of the part, and bonds to the substrate portion to form a unitary plastic panel. In the course of contacting the substrate portion, the plastic from the second injection folds and hides the non-adhered portion of the cover stock, thereby forming a neat, clean split line.

Abstract: The invention is to a transfer mold design utilized with conventional transfer encapsulation. The design utilizes a varying runner cross section with an intermediate varying depth well or reservoir from which a constant gate depth and gate entry angled to the mold cavities is employed. The method and apparatus of the invention is applicable to single and multiplunger molding utilizing thermoset and thermoplastic encapsulants for semiconductors.

Abstract: A segment used for producing a composite insulator having a core member and a housing member arranged around the core member and constructed by a trunk portion and a shed portion is disclosed. The segment has a pair of segment molds detachably connected at a partition plane and a heating and cooling passage arranged in the segment molds respectively. The segment molds have a through-hole through which the core member is arranged, an upper plane forming portion arranged at its one end surface for defining an upper plane of the shed portion, and a lower plane forming portion arranged at its other end surface for defining a lower plane of the shed portion. A heating or cooling medium is passed through the heating and cooling passage. Moreover, a mold is constructed by integrating a plurality of segments with the heating and cooling passage mentioned above.

Abstract: A multi-plate injection molding tool has multiple cavities. It includes a hot-runner plate, a hot-runner distribution block adjacent to the hot-runner plate, and a plurality of hot-runner nozzles. The hot-runner distribution block is a monolithic seamless metal block. A lower die plate is removably attached to the hot-runner plate, and an upper die bolster is adjustably attached to the lower die plate and is movable along fixed guide columns. The upper die bolster comprises a base plate, a stripping plate and a slide plate. A plurality of form cores are supported on the upper die bolster, and a plurality of annular stamps are attached to the lower die plate, each being around a form core and each having a conical exterior surface tapered towards the lower die plate, and cooperating with a die; a plurality of dies is carried by the lower die plate, and each has a mating conical surface for receiving the conical surface of a stamp in close fit therewith when the molding tool is closed.

Abstract: A system for injection molding a hollow plastic article utilizing a secondary resin flow path which communicates one portion of an article-defining cavity with a second portion of the article-defining cavity. The second portion of the article-defining cavity is typically the hardest-to-fill area of the article-defining cavity. The secondary resin flow path is outside of the article-defining cavity and the normal flow of plastic resin.

Abstract: The invention provides methods and apparatus in which mold material flows through a gate into a mold cavity that defines the shape of a desired part. An adjustable valve is provided that is operable to change dynamically the effective size of the gate to control the flow of mold material through the gate. The valve is adjustable while the mold material is flowing through the gate into the mold cavity. A sensor is provided for sensing a process condition while the part is being molded. During molding, the valve is adjusted based at least in part on information from the sensor. In the preferred embodiment, the adjustable valve is controlled by a digital computer, which includes circuitry for acquiring data from the sensor, processing circuitry for computing a desired position of the valve based on the data from the sensor and a control data file containing target process conditions, and control circuitry for generating signals to control a valve driver to adjust the position of the valve.

Abstract: A method is provided of forming a multi-pack container assembly having at least four containers joined together by a cross or plus shaped frangible web. The method includes the steps of providing at least one male mold member and at least one female mold member, disposing the mold members so as to define at least four container cavities separated by a cross or plus shaped web cavity, injecting the cavities with a plastics material to form the multi-pack container assembly, and releasing the multi-pack container assembly from the mold members. Preferably, the method is used to form multi-peck containers, such as yogurt or pudding containers, where each individual container can be easily separated from the multi-pack container assembly.

Abstract: A case houses a portable telephone apparatus having a display portion, an operating portion, a speaker portion and a microphone portion provided with respect to two main portions and a hinge portion which connects the main portions so as to be opened and closed. The case is formed of plastic molding. The hinge portion is formed of a soft resin having a resiliency, and the main portion is formed of a hard resin and integral with the hinge portion. A wiring member for provide an electric connection between the main portions extend through the hinge portion.

Abstract: A mold and injection molding process for the production of a fishing lure having multiple, integral bristles extending vertically from the lure. The mold defines an internal cavity in communication with an injection port and a ventilation port. The internal cavity defines a fishing lure having a desired shape. The cavity contains a pair of porous halves that facilitate the formation of integral bristles. Molten material is injected into the cavity through the injection port while air escapes through the ventilation port. The molten material penetrates the porous insert to form the bristles. The bristles are concurrently and integrally molded with the rest of the lure. After curing, the fishing lure is removed from the mold.

Abstract: A case for housing an electronic apparatus has two main portions and a hinge portion which connects the main portions so as to be opened and closed. The case is formed of plastic molding. The hinge portion is formed of a soft resin having a resiliency, and the main portion is formed of a hard resin and integral with the hinge portion. A wiring member for provide an electric connection between the main portions extend through the hinge portion. The wiring member passes at a center of rotation on which the hinge portion is turned.

Abstract: A magnetic plastic rotor disk manufacturing apparatus, includes an injection device for injecting a magnetic plastic material containing a synthetic resin matrix and a magnetic powder; a mold for molding the magnetic plastic material injected thereinto from the injection device, and a device for generating a magnetic field and magnetizing the magnetic powder in a direction along a diameter of the magnetic plastic rotor disks. The mold includes a three-plate type mold constructed of two retainer plates and a single runner stripper plate. One of the retainer plates is formed with a plurality of pin gates corresponding to the cavities so as to supply the magnetic plastic material through the pin gates into the cavities.

Abstract: The invention relates to a hollow injection-molding method of forming a hollow portion in molten resin in a mold cavity by introducing a pressurized fluid, and also to a pressurized fluid introducing and discharging apparatus therefor, and has an object of eliminating the backflow of the molten resin into a pressurized fluid passage. A gap between a cylindrical sleeve and a shaft core inserted into the sleeve is used as the pressurized fluid passage. The front end of the shaft core is projected into a mold beyond the sleeve front end to serve as a guide face. By sliding the shaft core, the state of an opening portion of the pressurized fluid passage in the side of the mold is changed between a narrowed state where the pressurized fluid can pass through the opening portion but the molten resin cannot enter the opening portion and a widened state allowing the pressurized fluid to rapidly discharge. The guide face allows the pressurized fluid to be reliably introduced into the mold cavity.

Abstract: A plurality of small-sized recesses are provided along outer peripheral edges of the openings of semispheric recessed portions in which a golf ball is injection-molded. These small-sized recesses form small-sized positioning juts along the parting line of a golf ball intended to be injection-molded.

Abstract: A machine for overmolding an equipment of an underwater cable includes a heated mold. The mold has a fixed half-mold with two side injection molding inlets and a mobile half-mold on a machine frame. These are coupled to a high-pressure injection molding press through an overmolding material distribution chamber and to the ends of the mold cavity. The machine finds an application in overmolding joint boxes and repeater housings.

Abstract: In a method and device for mold press forming involving distribution of molten resin within a mold including a plurality of valve gates, deformation of the product and generation of excessive burrs and voids are prevented by accurately distributing a prescribed amount of resin material to each valve gate by detecting the amount of molten resin supplied from an injection unit and controlling the opening timing and period of each valve gate. The amount of molten resin supplied from the injection unit can be conveniently evaluated by detecting the displacement of an in-line screw used in the injection unit. By providing a metering arrangement for each of the valve gates, the molten resin can be even more accurately distributed to each of the valve gates.

Abstract: The present invention provides an injection molding die unit having a simple construction and an injection molding method employing the injection molding die unit and capable of molding a composite molding in a short cycle time. After molding a first molding (70), a male die (30) is moved together with the first molding (70) by a distance (Gb) in direction (L) and, at the same time, a movable female die (14B) of a composite female die (14) is moved by the same distance (Gb) in the same direction (L) by a coil spring (29) to form a space (72) between the male die 30 and the composite female die (14) consisting of the movable female die (14B) and a fixed female die (14A), and a second molding material is injected into the space (72) to form a second molding (80).

Abstract: A pre-plasticization type injection molding machine is equipped with a plasticizing part for plasticizing synthetic resin material by turning a screw in a heating cylinder and an injection part for injecting the plasticized material through a nozzle by advancing and retreating an injection plunger into and from an injection cylinder. A conduit connects the tip of a plasticizing chamber, consisting of the heating cylinder, with the tip of an injection chamber consisting of the injection cylinder. The screw advances at the time of injection, closes the conduit with its tip. The opening of the conduit in the injection chamber is arranged on the periphery of a nozzle side-wall. An injection passage extends from the injection chamber toward the nozzle, the passage being open to the center of the nozzle side-wall.

Abstract: The present invention relates to an improved apparatus for forming injection molded plastic articles having an inner wall portion. The apparatus includes a mold cavity portion and a mold core portion defining a cavity space in the shape of the plastic article to be formed. The apparatus further includes at least two hot runner nozzles for injecting molten plastic material into the cavity space. The nozzles are preferably offset to outer portions of the mold core portion so as to provide an increased space in the mold core portion in which cooling conduits, inlets and the like can be placed to increase the cooling capability of the mold core portion. The offsetting of the nozzles also provides the mold core portion with increased strength. Each of the nozzles communicates with inner wall portion of the cavity space via a hook-shaped passageway and an inside gate. Additionally, each of the nozzles has a metal portion for maintaining plastic material in the hook-shaped passageway in molten condition.

Abstract: In an injection molding machine, a skin layer resin 26 is injected from a first hot runner 10b into a cavity C in a mold or molds and then a resin passage between the first hot runner 10b and the cavity C is closed, thereby finishing the injection of the skin layer resin 26. A core layer resin 28 is injected from a second hot runner 12b into the cavity C in the mold(s) at a predetermined timing during the period between the start and end of injection of the skin layer resin 26, thereby molding a sandwich molded product without hesitation marks.

Abstract: A fluid compressor has a cylinder (17), a rotary rod (21), and a helical blade (33) that defines work chambers (44) between the cylinder and the rod. The compressor successively compresses and conveys a fluid from a suction end to a discharge end through the work chambers according to the rotation of the rod. The continuous helical blade is formed by pressurizing and injecting synthetic resin material such as tetrafluoroethylene-perfluoroalkylvinylether polymer resin into a mold through two gates (39), so that a weld line (43) of the blade is located in an intermediate region between a suction pressure region and a discharge pressure region of the blade.

Abstract: An injection mold capable being filled from the center is a gated mold with at least one repositionable subgate. The subgate permits simplified removal of the central portion of the molded article, while at least substantially eliminating secondary treatment of the molded article.

Abstract: The present invention relates to an apparatus for injection molding a thin-walled plastic article with substantially equal thickness sidewalls, a base portion, and a lip portion. The apparatus includes a two part mold arrangement in which a first part defines has a mold cavity and a second part defines a mold core. The first and second mold parts in a mold closed position define a mold space in the shape of the article being molded. The apparatus further includes two or more gates adjacent a lip portion of the mold space for injecting molten plastic material into the mold space and a bottom center venting arrangement. The apparatus further includes a restriction in the mold space for improving the operation of the bottom center venting arrangement and providing a more balanced filling in a multi-cavity molding machine.

Abstract: The present invention provides a gate apparatus for injection molding, that enables injection-molding moldings having a relatively small height and forming a plurality of cavities in an associated injection-molding die, the number of the cavities being greater than that of the cavities of the conventional injection-molding die of the same size. The gate assembly comprises an injection-molding die having a female die provided with a cavity, a down gate having an upper cylindrical portion, a middle taper portion and a lower small cylindrical hole formed in the lower end of the middle taper portion, and a cross gate formed through a wall separating the cavity and the lower small cylindrical hole; and a nozzle chip having a lower taper portion of a shape conforming to the middle taper portion of the down gate.

Abstract: Apparatus for injection molding a plastic article having a hollow rib portion utilizing a spill cavity. A process includes the steps of sequentially injecting fluent plastic and gas into a mold cavity having a space defining at least one wall portion of the article and a channel defining a rib portion of the article. A quantity of fluent plastic is initially injected to substantially fill the mold cavity. A charge of pressurized gas is then injected into the channel of the mold cavity to displace a portion of the still fluent plastic into the spill cavity which is flow coupled to the channel. Preferably, the thickness of the rib portion in cross section is at least twice as large as the thickness of the wall portion in cross section along the entire length of the rib portion. Also, preferably, the channel is tapered along its length. The rib portion may be either internal or external to the article.

Abstract: In a method of injection-molding a thermoplastic resin wherein a weld is formed in the mold cavity by the fusion of separate resin streams, use is made of a mold provided with a resin well protruding from the molded cavity or a runner on at least one of the separate resin streams at a point between where the injected molten resin is separated into streams and the weld. The resin is poured into the resin well after the formation of the weld from the feed of the molten resin into the mold cavity to cause migration of the resin at the weld, thus forcing the resin on one side of the weld into the resin of the other side of the weld to thereby strengthen the weld.

Abstract: The present invention relates to a process and apparatus for injection molding thin-walled plastic articles. The apparatus includes a mold cavity and a mold core defining a cavity space in the shape of the article. The cavity space has a circumferentially extending region having a thickness greater than the thickness of a sidewall defining portion. This circumferentially extending region is preferably located at the approximate mid-point of the sidewall defining portion. At least two gates directly and simultaneously introduce plastic material initially into the circumferentially extending portion in a manner so as to minimize the creation of side loads and core shift. After the circumferentially extending region is filled, the plastic material fills the entire cavity space. The plastic material is thereafter cooled to form the desired article.

Abstract: In an injection molding machine, a skin layer resin 26 is injected from a first hot runner 10b into a cavity C in a mold or molds and then a resin passage between the first hot runner 10b and the cavity C is closed, thereby finishing the injection of the skin layer resin 26. A core layer resin 28 is injected from a second hot runner 12b into the cavity C in the mold(s) at a predetermined timing during the period between the start and end of injection of the skin layer resin 26, thereby molding a sandwich molded product without hesitation marks.

Abstract: The molding apparatus of the invention includes a molding cavity, a flow regulating portion and a degassing portion. The flow regulating portion is situated in a die to communicate between the molding cavity and the degassing portion and regulates molten material to pass through the flow regulating portion without forming turbulent flow therein. Therefore, the molten material enters into the degassing portion throughout the entire width of the degassing portion. Because of the flow regulating portion, the degassing portion may be made small, but the molten material can be properly solidified at the degassing portion without forming partial flow. Gas or air can be sufficiently removed from the die.

Abstract: Apparatus and method for molding plastic articles including oscillating the molten plastic in the mold cavity. The method and apparatus is particularly suitable for use with a plurality of mold cavities supplied from a single feeding means or extruder. The disclosure teaches alternately feeding molten plastic to the mold cavity from at least one shooting pot while the flow of molten plastic to the mold cavity from the feeding means is discontinued.

Abstract: An apparatus for use in fluid assisted injection molding of plastic material so as to form an injection molded product includes a pair of mold members defining when closed the sealed cavity, a first opening provided in one of the mold members for allowing the injection of plastic material into the cavity and the second opening provided in one of the mold members, and spaced from the first opening, for allowing the injection of the fluid into the cavity. A sleeve extends through the second opening. The sleeve has a longitudinally extending bore with an open first end. Preferably, the sleeve is rigidly secured in relation to the one of the mold members through which it extends. A pin extends through the sleeve with the pin having a first end, located adjacent the sleeve first end, and a second end. Preferably the pin is rigidly secured in relation to the sleeve. A fluid flow passage is defined between the pin and the sleeve. In another embodiment, the fluid flow passage is defined between a tube and a pin.

Abstract: An injection mold capable of being filled from the center is a gated mold with at least one repositionable subgate. The subgate permits simplified removal of the central portion of the molded article, while at least substantially eliminating secondary treatment of the molded article.

Abstract: The present invention provides a multi-ply molding hot-runner mold including a plurality of nozzle bodies for injecting a plurality of different resin materials to form a multi-ply product. The hot-runner mold comprises a plurality of hot-runner blocks each having a runner for conducting each resin material into the corresponding nozzle body. The hot-runner blocks are stacked one above another with a thermal insulation layer therebetween. Each of the hot-runner blocks includes temperature control means for maintaining the hot-runner blocks at its own molding temperature. Connecting blocks for conducting the resin material from the lower block to the upper block are provided between each adjacent hot-runner block. Between each adjacent hot-runner block there are provided holding members and thermal insulation layers.

Abstract: Apparatus and method for molding plastic articles including oscillating the molten plastic in the mold cavity. The method and apparatus is particularly suitable for use with a plurality of mold cavities supplied from a single feeding means or extruder. The disclosure teaches alternately feeding molten plastic to the mold cavity from at least one shooting pot while the flow of molten plastic to the mold cavity from the feeding means is discontinued.

Abstract: A mold for forming a magnetic tape cassette and a method for multi-color molding a magnetic tape cassette or the like. Sprue-runners connected to submarine gates used in making at least portions of the cassette are formed with notches near the submarine gates to reduce the cross-sectional area of the sprue-runners. As result, the sprue-runners can be easily cut off from the body of the cassette by breaking the notched portions.

Abstract: A duo-cavity multigang pot molding assembly (10) for encapsulating semiconductor devices having an annular cavity (11) to form a molded carrier ring and an inner cavity (12) adapted to receive the item to be encapsulated. An outer mold pot (16) provides encapsulating material for the annular cavity (11) whereas a separate mold pot (17) provides encapsulating material for the inner cavity (12). Encapsulating material for the mold pots (16, 17) may be the same or in a preferred embodiment, different. Molding apparatus (10) promotes improved process control by delivering encapsulating material with a lower and more uniform viscosity to both the annular cavity (11) and the inner cavity (12). Further, use of separate mold pots (16, 17) allows cost savings because a less expensive encapsulating material may be used for molding the molded carrier ring since a high purity encapsulating material is not needed.

Abstract: A method and an apparatus of injection molding articles of thermoplastic material. The method includes initially forcing molten plastics material into an injection mold in an amount sufficient for forming the article. Subsequently, a flowable medium is forced into the injection mold with a pressure which distributes the plastics material uniformly over the surface of the mold cavity of the injection mold so as to form a hollow body. The hollow body is then cooled while the pressure of the medium is maintained. Finally, the pressure of the medium is released and the molded article is removed from the injection mold. The pressure of the medium in the mold cavity is controlled and/or varied at least temporarily until the plastics material has cooled. The apparatus for carrying out the method includes a pressure reservoir for the medium which is connectible to the injection mold through lines. The lines include control and/or regulating elements.

Abstract: A unitary nozzle for use in a gas assisted injection molding process wherein the nozzle includes a central axial resin passageway, a land portion of the nozzle extends radially into the resin passageway proximate the downstream or discharge end of the nozzle to define a generally U-shaped resin passageway terminating in a U-shaped aperture at the nozzle tip, and a central gas passageway is provided on the central axis of the nozzle within the land portion and exiting the nozzle in a circular aperture embraced within the U-shaped resin aperture at the downstream end of the nozzle so that mixing of the resin and gas during the injection and venting processes is minimized and so that ingestion of resin into the gas passageway during the venting process is minimized.

Abstract: A molding process, includingsupplying molten, moldable material to a mold cavity;subjecting at least a part of the supplied molten material to a shear force;causing the material to solidify while maintaining the shear force; anddemolding the molded material.

Abstract: An apparatus for controlling a molding of a solid product in a mold cavity from molten material which solidifies in the mold cavity, in which first and second conduits are coupled to the mold cavity at spaced positions for carrying the molten material, includes first and second elements, and a controller for controlling the driving the first and second elements repeatedly during solidification of the molten material in the mold cavity so that the molten material is repeatedly moved through the mold cavity. The first element is disposed in the first conduit and the second element is disposed in the second conduit.

Abstract: An apparatus for injecting a viscous fluid such as a thermoplastic and a non-viscous fluid such as a gas into a mold cavity of a mold body includes a nozzle body having an inlet end, a discharge end and a flow passage for the viscous fluid extending from the inlet end to the discharge end. A valve element is mounted for reciprocation in the nozzle body flow passage to control the flow of the viscous fluid through the nozzle body discharge end. The valve element includes a barrel having a first end selectively engaging a portion of the nozzle body discharge end to prevent a flow of viscous fluid therepast and a second end. A bore extends longitudinally through the barrel. A pin is located in the barrel bore. The pin has a first end located adjacent to the barrel first end and a second end secured to the nozzle body such that the pin remains stationary as the barrel reciprocates in the nozzle body. A non-viscous fluid flow passage is defined between the pin and the barrel.

Abstract: An apparatus for use in fluid assisted injection molding of plastic material so as to form an injection molded product includes a pair of mold members defining when closed the sealed cavity, a first opening provided in one of the mold members for allowing the injection of plastic material into the cavity and the second opening provided in one of the mold members, and spaced from the first opening, for allowing the injection of the fluid into the cavity. A sleeve extends through the second opening. The sleeve has a longitudinally extending bore with an open first end. Preferably, the sleeve is rigidly secured in relation to the one of the mold members through which it extends. A pin extends through the sleeve with the pin having a first end, located adjacent the sleeve first end, and a second end. Preferably the pin in rigidly secured in relation to the sleeve. A fluid flow passage is defined between the pin and the sleeve. In another embodiment, the fluid flow passage is defined between a tube and a pin.