Abstract: A centering arrangement for controlling relative movement between a series of mold support plates in a stack mold having three or more levels. The centering arrangement uses a plurality of centering devices which are substantially identical, each spanning two mold levels and being connected to three adjacent mold support plates. Each centering device has a shaft generally parallel to an axis of the mold and having an intermediate portion journalled in an intermediate connector to allow rotational movement about a shaft axis, but to restrain relative axial movement between the shaft and the intermediate connector. Helical splines extend from the intermediate portion toward opposite ends of the shaft in oppositely twisting helices. End connectors having cooperating splines engage the splined portions of the shaft and connect the centering device to the outermost of the mold plates to which it is connected.

Abstract: A method of balancing the flow of a molten polymer containing material in a multi-runner injection mold includes the step of providing a mold body having at least one mold cavity and at least two runners. The first runner includes first and second ends and is connected to a source of molten material. The first runner is connected to a second runner. The second runner is connected to the at least one mold cavity. A stream of a molten polymer containing material flows through the first and second runners. The stream is repositioned in a circumferential direction as it flows from the first runner through the second runner while maintaining continuity between laminates of the stream of the molten material in a radial direction. In this way, a balance is provided for the melt temperatures and material properties of the cross branching runners.

Abstract: A molded article ejection device for use in conjunction with a multistation molding machine. The multistation molding machine has at least a first molding station defined between a first mold platen and a second mold platen and a second molding station defined between the second mold platen and a third mold platen, a mechanism for opening and closing the molding stations, and tie bars for connecting the first, second and third mold platens. Ejection devices are used for ejecting molded articles from each of the first and second molding stations and a linkage is used for connecting a plurality of the ejection devices and translating movement of at least one ejection device to at least one other ejection device. A motive mechanism is used for actuating the ejection devices, wherein the motive mechanism is independent of the mechanism for opening and closing.

Abstract: A method and apparatus for dividing the output flow of molten plastic from a conventional molding machine into a plurality of independent molten plastic flows to permit a plurality of plastic articles to be molded simultaneously from a single molding machine. The apparatus comprises a molding tool having a distributor member which divides the flow of molten plastic from an output port of a molding machine evenly into a pair of fluid flow bores. A pair of conventional flow nozzles are incorporated which receive the independent flow streams of molten plastic and independently charge a pair of molding cavities of a molding die generally simultaneously. The molding tool enables a more than 100% increase in the flow of molten plastic therethrough due to the reduction of back pressure seen by the molding machine and more than doubles the efficiency of the molding machine.

Abstract: The present invention relates to stack mold linkages for creating unequal strokes for use in an injection molding machine for making different sized molded parts. The stack mold linkages comprise linkages for moving each of at least two mold assemblies between a mold closed position and a mold open position and for separating the mold halves forming the mold assemblies by unequal stroke lengths.

Abstract: A cavity block and method for manufacturing such a block utilizes a computer assisted machining tool to form a composite cavity in a plurality of cavity block segments such that the segments can be separated after the machining of the cavity and paired in horizontal abutment rather than vertical abutment to reorient the lure or article about a new axis after the cavity has been created.

Abstract: A mold assembly includes a stack of mold plates having a first plate and a second plate movable towards one another and away from one another in opening and closing directions between open and closed positions. The stack of mold plates includes a third plate disposed between the first and second plates. The mold assembly also includes a plate movement control device having at least one linkage. Each linkage may include a traveling element mounted to the third plate for movement along a predetermined path of motion relative to the third plate, a first arm having a first end pivotally connected to the traveling element and a second arm having a first end pivotally connected to the second plate and a second end pivotally connected to the traveling element.

Abstract: Methodology for reducing the warpage in thinly packaged electrical components, and electrical components packaged according to the method. The method taught herein is to make the gates themselves compliant, or flexible, thereby absorbing the stresses which would otherwise cause package deformation, including warpage. The present invention teaches two preferred embodiments for attaining this novel solution, including the adoption of wide, thin gates and the use of serpentine gates.

Abstract: A method of and an apparatus for molding resin to seal electronic parts are adapted to use molding units to seal with molded resin materials electronic parts that are mounted on lead frames. Additional molding units are detachably mounted with respect to an already provided first molding unit in the molding apparatus, so that the number of the molding units can be arbitrarily adjusted. In this manner, the method and apparatus can be easily reconfigured or rearranged to be adapted to mass production or small production runs of the same or different types of molded parts. By simultaneously carrying out various process steps, the overall process time is reduced.

Abstract: A mold assembly for manufacturing an outsole includes a female mold, a first male mold pivotally connected to a side of the male mold and a second male mold pivotally connected to an end of the male mold. A peripheral wall defining the cavity has a separating flange extending inwardly therefrom. Each of the first male mold and the second male mole has at least one protrusion extending therefrom through which at least one passage is defined. The protrusion of the first male mold is inserted into the cavity and an outer surface of the protrusion abuts the separating flange. The first protrusion and the second protrusion are inserted into the cavity in sequence and material is injected into the cavity via the passages.

Abstract: A multi-cavity coinjection mold having a relatively large plurality of cavities for simultaneously molding a relatively large plurality of multi-layered articles including a) a plurality of cavity groups each defining a relatively small plurality of said cavities, a single balanced hot runner for supplying said relatively small plurality of cavities with contiguous different plastics materials, and a valve for sequentially supplying desired contiguous quantities of the plastics materials from plastics material sources, common to all of said groups, to the balanced hot runner; and b) a hot runner manifold system connected to the plastic material sources to supply the plastic materials to all of the valves; and related methods.

Abstract: A sprue bar assembly for a melt transfer system for stack molds comprises a sprue bar and a sprue bar sleeve, a sprue bar and drool restrictor and sleeve or a sprue bar and drool restrictor. For the assemblies with the sleeve, when the stack mold is opened, the sprue bar slides inside the sprue bar sleeve which captures any leakage therefrom. When the mold is closed, the sprue bar sweeps captured leakage out of the sleeve to an area outside the mold. As the busing at the end of the sprue bar can contact the nozzle of the injection machine at a point very close to the edge of the fixed platen, the resulting minimum length of the sprue bar is reduced, reducing pressure losses through the sprue bar and reducing the cost of the sprue bar. The sprue bar sleeve can be fabricated from an insulating material to enhance the thermal characteristics of the sprue bar assembly and a scraper can be provided on the sprue bar to improve removal of captured material from the sprue bar sleeve.

Abstract: The present invention relates to an apparatus and method for producing molded polyester articles. More particularly, the invention concerns an apparatus and method for continuously producing molded polyester articles having low acetaldehyde content from a melt prepared by continuously reacting polyester precursors. The polyester is prepared and formed into useful shaped articles in a single, integrated, continuous melt-to-mold process without an intermediate solidification of the melt.

Abstract: A mold system for encapsulating substrate-mounted ICs comprises a split mold having a lower cavity adapted for positioning the substrate and an upper cavity adapted for providing a volume space around the IC. The lower cavity is provided with a compressible shim plate adapted to lie on a bottom surface of the lower cavity such that a substrate of a substrate-mounted IC placed in the lower cavity will extend above the upper limit of the lower cavity, which is the split surface of the mold. As the split mold is closed, a lower surface of the upper mold portion encounters first an upper surface of the substrate, then the compressible shim plate is compressed until the mold is fully closed, at which time the lower surface of the upper mold portion is in intimate contact with both the substrate and the upper surface of the lower mold portion. The IC mounted on the substrate is then presented in the upper cavity for encapsulation.

Abstract: A method and apparatus for encapsulating an integrated circuit die and leadframe assembly using liquid mold compound. A prepackaged liquid mold compound insert 11 is placed in a rectangular receptacle 43 in a bottom mold chase 31. The receptacle 43 is coupled to a plurality of die cavities 37 by runners 39. Leadframe strip assemblies containing leadframes, integrated circuit dies, and bond wires coupling the leadframes and dies are placed over the bottom mold chase 31 such that the integrated circuit dies are each centered over a bottom mold die cavity 35. A top mold chase 53 is placed over the bottom mold chase 31 and the mold compound package 11. The top mold chase 53 has die cavities 57 corresponding to those in the bottom mold chase 31. The prepackaged liquid mold compound is packaged in a plastic film which has heat sealed edges 15. The mold compound is forced through the heat seals 15 during the molding process by the pressure applied by a rectangular plunger 61.

Abstract: A mold set for encapsulating semiconductor chips on lead frame strips with a molding compound supplied in tablets, includes a pot where molding compound tablets are loaded and pressed to form a fluid molding compound (FMC), and a main runner connected to the pot, through which the FMC passes from the pot. A plurality of sub-runners are connected to the main runner and are oriented substantially radially from a center region of the main runner. Each sub-runner has a proximal end, where it joins the main runner, and a distal end. A plurality of cavities are disposed on both sides of the main runner. Each of the plurality of cavities is in flow to communication with the distal end of a respective one of the plurality of sub-runners. The present invention allows the FMC to be introduced into all cavities at nearly the same time and at nearly a constant velocity.

Abstract: A method of manufacturing a semiconductor component includes forming a vertical side seal for a runner in a first mold plate by mating a protrusion of the first mold plate with a protrusion of a second mold plate. As an encapsulating material is forced through the runner, the vertical side seal prevents an encapsulating material from leaking out of the edge of the runner.

Abstract: A process and apparatus for distributing molten thermoplastic material supplied directly from melt polymerization to a plurality of molding machines operating in timed sequence is disclosed. The invention is particularly applicable to transferring molten polyester (normally polyethylene terephthalate or a copolymer thereof) directly from a melt polymerization reactor to injection molding machines for producing molded plastic articles.

Abstract: A manual loader for use in bypassing an automatic pellet feeder for an automold machine used to encapsulate integrated circuit assemblies in plastic. The loader has a support mounted adjacent the mold section of the machine. The loader also has at least one pellet boat which moves relative to the support into and out of said mold section. The pellet boat includes one or more pellet pots which are adapted to receive and hold a solid pellet of material. The loader has a release mechanism which is movable between a blocking position and a release position. The release mechanism retains the pellets in the pellet pots in the blocking position and releases the pellets from the pots when manipulated to the release position for dropping the pellets into a mold of the machine's mold section.

Abstract: The present invention relates to an apparatus for forming semiconductor chip packages which is able to compensate for the flatness of substrates and the true straightness of edges of substrates, which substrates are inserted in molds in a forming process of semiconductor chip packages. According to the present invention, the semiconductor package strips excellent in surface flatness and side straightness of a substrate can be manufactured, because the thickness deviation and the side nonuniformity of a substrate can be compensated for in the resin molding process of the semiconductor package by use of a forming apparatus which comprises the individual cavity blocks, elastically mounted so as to float up and down, and the elastic pressing members, mounted on one end of the upper and lower chases.

Abstract: A method and apparatus for encapsulating an integrated circuit die and leadframe assembly. A prepackaged sproutless mold compound insert 71 is placed in a rectangular receptacle 91 in a bottom mold chase 81. The receptacle is coupled to a plurality of die cavities 85 by runners 87. Leadframe strip assemblies containing leadframes, integrated circuit dies, and bond wires coupling the leadframes and dies are placed over the bottom mold chase 81 such that the integrated circuit dies are each centered over a bottom mold die cavity 85. A top mold chase 90 is placed over the bottom mold chase 81 and the mold compound package 71. The top mold chase 90 has die cavities 95 corresponding to those in the bottom mold chase 81. The mold compound insert 71 is preferably packaged in a plastic film 75 which has heat sealed edges 77. The mold compound is forced through the package 75 and heat seals 77 during the molding process by the pressure applied by a rectangular plunger 101.

Abstract: A sprue bar assembly for a melt transfer system for stack molds comprises a sprue bar and a sprue bar sleeve. When the stack mold is opened, the sprue bar slides inside the sprue bar sleeve which captures any leakage therefrom. When the mold is closed, the sprue bar sweeps captured leakage out of the sleeve to an area outside the mold. As the bushing at the end of the sprue bar can contact the nozzle at a point very close to the edge of the fixed platen, the resulting minimum length of the sprue bar is reduced, reducing pressure losses through the sprue bar and reducing the cost of the sprue bar. The sprue bar sleeve can be fabricated from an insulating material to enhance the thermal characteristics of the sprue bar assembly and a scraper can be provided on the sprue bar to improve removal of captured material from the sprue bar sleeve.

Abstract: A molded article ejection device for use in conjunction with a multistation molding machine. The multistation molding machine has at least a first molding station defined between a first mold platen and a second mold platen and a second molding station defined between the second mold platen and a third mold platen, a mechanism for opening and closing the molding stations, and tie bars for connecting the first, second and third mold platens. Ejection devices are used for ejecting molded articles from each of the first and second molding stations and a linkage is used for connecting a plurality of the ejection devices and translating movement of at least one ejection device to at least one other ejection device. A motive mechanism is used for actuating the ejection devices, wherein the motive mechanism is independent of the mechanism for opening and closing.

Abstract: Apparatus of injection molding three-layer moldings, especially bottle blanks with an inner and an outer layer of polyethylene terephthalate and a middle layer of recycled polyethylene terephthalate, employing a mold with several cavities. The material (component A) for the inner and outer layers is supplied through one molten-component conveying channel and the material (component B) for the middle layer through another molten-component conveying channel. The channels are separately heated and their temperatures independently regulated. The melt for component A flows the same distance as the melt for component B. The melts flow into the injection-molding dies such as to ensure a uniform front.

Abstract: The automatic molding machine of the present invention comprises: molding dies; a press mechanism to which the molding dies are attached, the press mechanism clamping and molding a work piece which is set in the molding die; a film feeding mechanism linking with molding action of the press mechanism, the film feeding mechanism feeding release film, which is formed into a long belt form, prescribed length so as to correspond a setting position of the work piece, which is set in the molding die; and a conveying mechanism linking with the molding action of the press mechanism, the conveying mechanism feeding the work piece and resin for molding into the molding die and taking out a molded product therefrom, wherein the work piece is molded by the molding dies whose molding sections are covered with the release film.

Abstract: A process is disclosed for producing reinforced twin-sheet thermoformed articles comprising the steps of heating first and second sheets of thermoplastic material; forming the sheets in molds; heating a reinforcing insert of thermoplastic material; placing the heated insert on the first sheet in its mold at the location to be reinforced; pressing the second sheet into contact with the heated first sheet and the heated insert to form the insert between the sheets so that a fusion of the thermoplastic sheets and the insert takes place to produce a reinforced section of the article having a desired shape and thickness. Alternative processes are disclosed wherein a heated quantity of thermoplastic liquid material is extruded or injected between the first and second sheets within the first and second molds either by inserting the liquid material before the molds are closed or by injecting it through one of the molds.

Abstract: A multi-colored lens assembly is produced in a multi-station injection molding apparatus having non-indexing ejector halves and indexing cover halves. Material is shot on an unexposed illumination side of the lens assembly from valve gated nozzle drops contained in the non-indexing ejector halves thereby producing a viewing side of the lens assembly free of surface blemishes and surface stress defects. Lens assemblies are retained in the indexing cover halves by retention mechanisms provided to overlap peripherally extreme features of the lens assemblies. Lens assemblies are affirmatively released from the non-indexing ejector halves by ejection pins or blades simultaneously with parting of the mold halves.

Abstract: A gate portion constituting a gate of a resin molding die is made of a hard alloy having a hardness greater than the predetermined hardness in the iron-based hard alloy used to from a cavity block and a center block. Opposing surfaces of the cavity block halves include a silicone rubber layer at least at the portions thereof which contact portions of the lead frame in a semiconductor encapsulation molding apparatus.

Abstract: Balanced injection molding in a multi-cavity mold of a plurality of ridged-wall products having is accomplished by providing mold parts defining therebetween at least two cavities for forming the ridged-wall plastic products, wherein each of at least two cavities defines a plurality of flow channels in which injected plastic material flows within the cavity and in which flow channels the first side strips are formed; wherein the relative disposition of the mold parts is adjustable for adjusting the dimensions of the flow channels in at least two mold cavities separately so that when plastic material is injected approximately simultaneously into the at least two mold cavities the injected plastic material flows within the at least two cavities at respective flow rates that cause the at least two mold cavities to be completely filled approximately simultaneously with the injected plastic material.

Abstract: A device for encapsulating a plurality of semiconductor die comprises a form having first and second halves such that as the first half contacts the second half the first and second halves have a plurality of cavities therein. The first and second halves each comprise a conduit therein for receiving a heated liquid. The device further comprises a runner block having a hole therein, a separate runner for each cavity, and a conduit therein for receiving a heated liquid. The runners have a rectangular cross section and a width to height ratio of at least 3:1. The device further comprises a mounting plate for mating with the runner block. The mounting plate comprises a concave recess and a hole in the mounting plate at the recess. The hole in the mounting plate passes through the mounting plate to align with the hole in the runner block such that an encapsulation material can be passed between the mounting plate and the runner block.

Abstract: An improved transfer molding apparatus has a laminated chase block with many sets, which is capable of fabricating a plurality of semiconductor packages. The apparatus includes an upper plate and a movable lower plate and a plurality of posts disposed between the upper and lower plates. A plurality of laminated chase blocks is fixed to the posts. A plurality of ejecting means are disposed at one side of the chase blocks and supply means concurrently supplies a molding compound to the plurality of chase blocks.

Abstract: An innovative method and apparatus for synchronizing the flows of molten polymer or similar materials in molding systems which utilize manifolds to direct flow into one or more cavities of an injection mold. The apparatus utilizes intermeshing positive displacement, interconnected gearing systems similar to positive displacement gear pumps in hydraulic systems. These positive displacement gear mechanisms are placed in each parallel flow channel such that all flow in each channel passes through a gear mechanism. Each of the parallel pumps are connected together directly via a shaft or indirectly using hydraulic motors, stepper motors, or other motors to synchronize the parallel flows. Each flow can be different to allow the directing of flows in complex tools or when molding parts in family molds.

Abstract: Balanced injection molding in a multi-cavity mold of a plurality of ridged-wall products having is accomplished by providing mold parts defining therebetween at least two cavities for forming the ridged-wall plastic products, wherein each of at least two cavities defines a plurality of flow channels in which injected plastic material flows within the cavity and in which flow channels the first side strips are formed; wherein the relative disposition of the mold parts is adjustable for adjusting the dimensions of the flow channels in at least two mold cavities separately so that when plastic material is injected approximately simultaneously into the at least two mold cavities the injected plastic material flows within the at least two cavities at respective flow rates that cause the at least two mold cavities to be completely filled approximately simultaneously with the injected plastic material.

Abstract: A molding die set includes an upper die having an upper cavity; and a lower die including a lower cavity to be arranged to face the upper cavity, and a gate which guides plasticized resin into the lower cavity and the upper cavity. The lower cavity is provided with a projection region which is projecting inwardly. The gate is arranged to be extending in the projection region.

Abstract: Real time distance and pressure data of a plunger (35) relative to a mold compound is provided by a compensation assembly (29) in a mold press (10). The compensation assembly has a sliding block assembly (30) which moves substantially in the same direction as the plungers (35). The sliding block assembly (30) has pressure control cylinders (33) which limit the pressure plungers (35) can apply. If the pressure on the plungers (35) should exceed this limit, the plungers (35) retract towards the sliding block assembly (30). A sensor (37) is coupled between the sliding block assembly (30) and the plungers (35) to measure the distance the plungers have moved towards the sliding block assembly (30). In one application, the sensor (37) is formed from a linear voltage displacement transducer (LVDT) so the mold press (10) can have real time pressure and distance data.

Abstract: An apparatus and method for injection molding of thermoplastics has elements and steps comprising mating mold components having multiple mold cavities with flow passages and a plurality of conduits connected to the mold cavities so that thermoplastic can flow into the cavities. A plurality of flow control members are mounted relative to the mold and to corresponding conduits to be moved to regulate the flow of plastic through corresponding conduits into corresponding cavities to allow for controlling the rate of thermoplastic flow among the cavities. The flow control member can each have a first member movable into its corresponding conduit, and a second adjusting member movable to engage and move the first member. A biasing member can be provided to bias the first member relative to its corresponding conduit. The control members can be inserted to varying degrees within their corresponding conduits to control thermoplastic flow rate among the mold cavities.

Abstract: A method and apparatus for distributing melt through three level stack molds. According to the method a crossover manifold is provided between adjacent mold levels of the stack mold, the crossover manifold having a plenum generally coaxial with a mold axis. Melt is introduced into the plenum through an inlet passage and distributed from the plenum to respective nozzle arrays through a separate outlet conduit associated with each mold level. The apparatus includes a crossover manifold mounted between first and second mold levels and having a plenum generally coaxial with the mold axis. An inlet conduit fluidly communicates with the plenum and an injection head to provide a melt path from the injection head into the plenum. A separate outlet conduit is provided for each mold level.

Abstract: Multi-cavity injection molding apparatus having two heated manifolds interconnected by a connector bushing all extending in a common plane. A threaded portion of the connector bushing is screwed into a threaded opening in one manifold and a nonthreaded portion of the connector bushing is received in a nonthreaded opening in the other manifold. The nonthreaded portion of the connector bushing fits in the nonthreaded hole in the other manifold tightly enough to prevent melt leakage, but is still able to slide sufficiently in the opening to accommodate thermal expansion and contraction of the heated nozzles relative to the cooled mold in which they are mounted and located. In one embodiment, the connector bushing is made of a material such as a beryllium copper alloy having a greater coefficient of expansion than the steel manifolds so it can be easily installed and then expand to produce this fit when heated to the operating temperature.

Abstract: Retroreflective prisms are formed with windows thereon by removing a portion of the prism mold on one prism pair leaving the apex of the prism intact. In this manner smaller prisms are formed adjacent larger prisms. Optionally, the optical axis of the prisms may be tilted with respect to one another, preferably in a negative direction. The smaller prisms with windows provide increased brightness and optimize the retroreflection light.

Abstract: The invention covers an injection molding apparatus and injection molding process. The apparatus has at least a first and second injection molding machine adjacent one another, with each machine including upper and lower mold elements operative to form molded products; and robot adjacent said injection molding machines operative to remove and replace at least a portion of one of said mold elements from a first of said injection molding machines while the second of said injection molding machines continues to form molded products.

Abstract: A method and apparatus for a nonsynchronous system for continuously molding articles from a material cured by the control of temperature and pressure. The apparatus includes a multi-section self-clamping mold, a controller system, a material injector, a transfer system, a curing apparatus for curing the articles, and a mold separator-assembler. The method comprises pre-treating and then assembling the mold in a clamped condition. Under the control of the controller system, the mold is then injected with material from the injector, and moved by the transfer system through the curing apparatus to cure the material within the mold. Once cured, the controller system moves the mold to the mold separator-assembler via the transfer system. The mold is then disassembled into sections, the molded article is removed, and the sections are pre-treated and reassembled, for the next injection operation.

Abstract: A method and apparatus for resin molding upon an insert-member. The molding machine includes an upper die and a lower die, a cavity in at least one of the dies, a pot in which resin is introduced, and a resin path which allows the resin to flow from the pot into the cavity and onto the insert-member set in the dies. A film member is set between a parting face of the die and the insert-member. The film member covers a part of the insert-member corresponding to the resin path. An edge of the film member coincides with at least one of side edges of the cavity. The insert-member is clamped by the dies together with the film member when molding occurs.

Abstract: Edge gated injection molding apparatus wherein each heated nozzle has the combination of a circular sealing ring extending around it and several gate inserts, each extending radially outward from the nozzle in alignment with a gate. The sealing ring bridges an insulative air space between the heated nozzle and the surrounding wall of a well in the cooled mold to provide a sealed portion of the space around the gate inserts. The outer end of each gate insert is spaced a predetermined distance "D" from the wall of the well in which the nozzle is seated to form an opening therebetween. The opening is large enough to allow pressurized melt to flow outwardly therethrough into the sealed front portion of the space between the nozzle and the surrounding wall of the well and small enough to prevent the partially solidified melt in the sealed front portion of the space being sucked back into the melt stream during subsequent injection cycles.

Abstract: A moving mold 100 consisting of slidable housing molds 110 and 110 and retainer molds 120 and 120 and a fixed mold 200 pairing with the moving mold 100 are used to mold a housing 20 and retainers 30a and 30b in resin at the same time. When the fixed mold 200 and the moving mold 100 are opened, the housing molds 110 and 110 are opened and a space is formed between the housing 20 and the retainers 30a and 30b to be fitted to each other. The retainers 30a and 30b are pressed against the housing 20 with the retainers 30a and 30b held in the retainer molds 120 and 120 from both the left and right sides, whereby the housing 20 and the retainers 30a and 30b are assembled.

Abstract: A manifold for a hot process injection molding apparatus includes a two piece manifold assembly. A first manifold section which includes a longitudinal melt channel and a nozzle drop to a mold is fixably secured to a manifold cavity of the apparatus. A second manifold section also including a longitudinal melt channel is sealably and slidably coupled with the first manifold section for fluidly communicating molding material from the second melt channel to the first melt channel. Expansion and contraction of the manifold sections are taken up by the slidable coupling.

Abstract: A method of resin molding for molding regular products and a resin molding machine for the same. In the method of the present invention, release film, which is capable of easily peeling off from molding dies and resin, is provided on faces of the molding dies. A member to be molded by the molding dies is clamped together with the release film. An inner face of a pot of the molding die is covered with the release film. A resin tablet is supplied into the pot.

Abstract: Molds for injection molding tire components have controlled temperature passages leading to a manifold surrounding each mold cavity. The manifold is positioned to minimize weld lines in the injected tire component. In addition, a narrow gate opening between the manifold and mold cavity provides an elevated temperature of the injected material for decreasing the curing time of the tire component in the mold. Blade members may support and position tire components such as bead apex assemblies in the mold. These tire components may be unloaded by an unloader ring in communication with a source of vacuum for pulling the tire component out of the mold.

Abstract: Multi-cavity injection molding apparatus having several melt distribution manifolds interconnected by elongated connector bushings. Each connector bushing has an outer sleeve which fits over a nonthreaded cylindrical portion of the main body. The main body is made of a material such as steel with sufficient strength that thermal expansion pushes the manifolds into operating positions slightly further apart without damaging the connector bushings. The outer sleeve of each connector bushing is made of a material such as copper having a coefficient of expansion sufficiently greater than the main body whereby thermal expansion results in the connector bushing forming a seal against melt leakage.

Abstract: A method which makes it possible to simultaneously injection-mold a number of spherical moldings without causing increase of runner loss, and is a method of preparing spherical moldings by coupling molding forming parts with each other through a bridge of 0.1 to 10 mm.sup.2 in sectional area for feeding molten resin, arranging a structure in which a plurality of molding forming parts are coupled with each other through the aforementioned bridge with respect to one gate, and performing molding, thereby obtaining a sphere series in which a plurality of spherical moldings are coupled with each other through a bridge part.

Abstract: Balanced injection molding in a multi-cavity mold of a plurality of ties having a uniform maximum thickness between opposite broad sides of the tongue of the tie is accomplished by providing mold pieces in which the relative dimensions of projections for forming ratchet teeth on the tongue of the ties in different mold cavities are non-uniform such that when plastic material is injected into the mold cavities, the injected plastic material flows through the different mold cavities at respective flow rates that cause the mold cavities to be completely filled approximately simultaneously with the injected plastic material. In making the mold pieces, the dimensions of the projections initially are larger than required for forming ratchet teeth of a preferred dimension.