Abstract: A device for injection molding articles of plastics material having hollow spaces. The device includes a molding tool with a mold cavity. Plastics material melt is fed to the mold cavity through a nozzle. Another pressurized medium is supplied to the mold cavity through a hollow needle at a location different from the location of the nozzle. A needle core is mounted in the hollow needle. The needle core is axially displaceable within certain limits. The opening of the hollow needle to the mold cavity can be opened and closed or its cross-sectional area can be varied by moving the needle core.

Abstract: A process for securing a component inside a hollow body essentially made of thermoplastic material includes positioning the component in the hollow body during its manufacture by means of a support. The component is secured by being hot-plated between two opposed faces of the hollow body.

Abstract: A handle assembly having a one piece molded handle that is mounted to an extension tube and that has an integrated switch for use with a floor supported appliance is provided. The handle includes a loop-shaped grip portion, an elongated portion in which an extension tube is mounted, and a switch mounting port for mounting the switch in the handle. The handle includes a minimum number of parts and does not require fasteners for mounting it to the extension tube. A method for making the handle is also provided.

Abstract: A method and system for injection molding plastic articles which utilize a spill area whose volume varies within an article-defining mold cavity. In one embodiment, the volume increases during introduction of pressurized gas into the mold cavity. In another embodiment, the volume of the spill area varies during a plastic injection which fills the mold cavity. A core reciprocally mounted within the mold cavity partially defines the variable volume of the spill area. An air spring is utilized to control pressure on the core which counters the pressure of the plastic at an end face of on the core. In one embodiment, the end face of the core is non-flat to create an area where fluid plastic can exert pressure against the end face within the mold cavity during plastic injection and/or during introduction of pressurized gas.

Abstract: Apparatus for fluid-assisted injection molding systems or co-injection molding systems. A pair of concentric movable pin members are positioned in a mold bushing and selectively controlled to facilitate or prevent the passage of molten plastic material and a fluid into the mold cavity. An inner pin member is positioned within a hollow pin member and both pin members are controlled by piston members which are selectively moved in a block member by selective pressurization from a hydraulic or pneumatic source. Movements of the piston members selectively controls the operation of the pin members and thus the operation of the fluid-assisted injection molding system.

Abstract: A process for the injection molding of objects having an outer layer of enamel and an inter layer of a plastic material is disclosed. According to the process, a liquid enamel is used. This enamel is injected by an enamel-injection apparatus through an enamel-injection die. A plastic melt passes through an injection unit into the cavity. According to the invention, the liquid enamel is injected into the flow path of the melt in the region before the cavity, before the melt is injected, so that the melt is encased by enamel before it is distributed in the cavity. Variations are also disclosed. For example, the form can be filled with enamel and the excess enamel drained. Then, the melted plastic material is introduced into the injection molding form. Also, the form can filled and then the capacity of the form increased to accommodate the melted plastic material. In any case, it is possible to use liquid enamels to enamel injection molded parts in the tool or form.

Abstract: A mold for use in a gas-assisted injection molding system includes an adjustable overflow pin assembly which includes a conical stack of shims which are removably secured to an ejector pin to move therewith within a conically-shaped spill cavity flow-coupled by a secondary runner to an article-defining cavity of the mold. The mold also includes a blocking pin assembly which together with the adjustable overflow pin assembly are mounted on an ejector plate to move therewith between extended and retracted positions of the ejector plate. The blocking pin assembly includes a blocking pin which is slidably fit within the second mold half to move relative to the ejector plate between an extended blocking position to block the flow of molten plastic through the secondary runner and a retracted position to allow the flow of molten plastic through the secondary runner and into the spill cavity.

Abstract: A method is provided for injection molding of parts in a mold having a mold cavity. The method comprises: 1) supplying pressurized fluid to a mold cavity prior to injection; 2) injecting a combination of non-mixable materials into the mold cavity against the pressurized fluid, thereby creating a resultant internal counterpressure within the combination of materials; and 3) maintaining the internal counterpressure within the combination of materials sufficiently to cause the materials to solidify in a predetermined configuration based on their respective modulus.

Abstract: A vehicle article carrier having a pair of one-piece, integrally formed side rail members. Each side rail member has a side rail portion and a pair of end supports integrally formed with terminal ends of the side rail portion. The side rail portion includes a hollow area formed therein and extending along the entire length of the side rail portion. Each end support further includes an inaccessible hollow portion in communication with the hollow portion formed in the side rail portion. Each side rail member forms a lightweight yet rigid member which does not require molding lines, seams or other markings on any portion of the outer surface which is clearly visible to an observer once the side rail members are mounted on an outer body surface of a vehicle. The cost of manufacture is also reduced because the number of molding tools needed to manufacture the side rail member is reduced, as is the complexity and time to assemble the side rail members to an outer body surface of a vehicle.

Abstract: A compostable multilayer film includes a core layer having a first surface and a second surface, a first blocking reducing layer covering the first surface of the core layer, and a second blocking reducing core layer comprises a lactic acid residue-containing polymer having a glass transition temperature (Tg) below 20.degree. C. The first and second blocking reducing layers comprise a semicrystalline aliphatic polyester. The hydrolyzable polymer and have a T.sub.g above about 50.degree. C. The multilayer structure can be used for preparing bags and wrappers.

Abstract: Disclosed is an injection-molded hollow article having large hollow portions 1 which securely provide the strength required by the injection-molded hollow article without depending upon ribs as more solid remaining portions being unstable in position and size.A melted resin and pressurized fluid are injected under pressure into a metal mold cavity 4, a movable core 5 projected into the metal mold cavity 4 is moved and then a support portion 2 is formed at the position from which the movable core 5 is moved.The position and size of the support portion 2 can be determined by selecting the position and size of the movable core 5.

Abstract: Mold bushings or nozzles for gas-assisted injection molding processes are disclosed. The devices include movable shut-off mechanisms which selectively facilitate or prevent the passage of molten plastic material into mold cavities. One or more apertures, such as holes, openings, channels, slits, slots, and the like, are provided at or adjacent the end of the pin members or at the end of the devices. The apertures are thin or small and have dimensions which will allow the passage of gas and at the same time prevent the plastic material from plugging or clogging them.

Abstract: The invention relates to a process of and an apparatus for injection molding hollow-blown plastic bodies in which a mold cavity formed by a tool and consisting of at least one main mold cavity and one side mold cavity is filled with a pressurized flowable plastic melt and, after the setting in of the hardening of the plastic melt at the walls of the mold cavity, a pressurized fluid is introduced into the main mold cavity, and, with this, the flowable core of the plastic melt is forced out of this main mold cavity, and subsequently, a pressurized fluid is introduced into the side mold cavity by means of which the flowable core of the plastic melt is forced out of the side mold cavity into the main mold cavity, where the material still capable of flowing is deposited on the already hardened walls in the main mold cavity.

Abstract: The present invention presents a fluid flow process analyzing apparatus and method, an injection molding process analyzing apparatus and method, an injection molded product and an injection molded product producing method, in which a three-dimensional model divided into a plurality of small elements to present a cavity where fluid flows is used for analyzing a process of fluid flow such as injection molding process in a practical computing time. The fluid flow process analyzing apparatus and method of the present invention comprises; constructing a three-dimensional model divided into a plurality of small elements to represent a cavity where fluid flows, determining the flow conductance .kappa. as a small value when the small element concerned is located close to the cavity wall surface and as a large value when the small element is located far away, and computing the pressures, pressure transitions or flow velocities at the respective small elements based on the flow conductances determined.

Abstract: A blow molded container is provided which includes a neck portion having locking teeth with features which ensure the proper formation of the teeth. Specifically, the container neck portion includes an annular inclined surface extending from both the upper and lower sides of the teeth, while all edges of the teeth are rounded. The annular inclined surfaces and the rounded edges ensure that the teeth are formed with sufficient material to ensure strong, sturdy teeth devoid of weak areas, holes or cracks. A method of forming the container is also provided which includes rounding all edges of the teeth as a parison abuts molds so as to inhibit undesirable stretching of the material forming the teeth. The method may also include forming the annular inclined surfaces to further inhibit undesirable stretching of the material forming the teeth thus ensuring proper formation of the teeth.

Abstract: A multiple limbed component is molded in a gas injection mold with a corresponding number of outlets. The outlets are regulated by valves that are operated sequentially to permit progressive expulsion of the excess material in the mold cavity.

Abstract: A gas nozzle for a gas assisted injection molding system includes a body having an inlet in fluid communication with a source of pressurized gas, an outlet through which the gas leaves the nozzle and a passage extending between the inlet and the outlet. The outlet includes a plurality of apertures arranged in a predetermined manner relative to one another such that the flow path through the outlet approximates a 1/8 inch hole but does not clog with resin over successive plastic injections into the mold.

Abstract: The invention relates to a method for fabricating hollow plastic objects of thermoplastic material, having the following steps: a) injecting melt into the tool cavity (1, 2); b) Simultaneously and/or subsequently introducing a pressurized fluid into the melt, so that the melt which has been introduced into the molding tool (1, 2) is distributed in the cavity and is pressed against the walls of the molding tool (1, 2), the pressurized fluid being conducted from a pressurized container (5) into the melt, and the pressurized container (5) being supplied with fluid by a compressor (7) which contains a drive element (6); c) allowing the molded part (8) to cool; and d) relieving the cavity of the pressure of the pressurized fluid. According to the invention, the drive element (6) of the compressor (7) is maintained at a temporally constant power level (P) at least over the production of a large number of plastic objects.

Abstract: Trim panels for motorvehicles are manufactured by: injection molding a panel base portion having missing parts of predetermined area and shape, said molding involving the coinjection of a surface material and of an inner core material; separately producing a plurality of portions of panel having area and shape substantially corresponding to the missing parts and fastening said separately produced portions to said panels.

Abstract: A process for making injection molded articles having a substantially smooth outer surface and a foamed core by injecting a molten thermoplastic into a mold, and, when the outer surface has formed, injecting a gas under pressure into the mold whereby a limited amount of molten material flows back into the injection unit to create a hollow space in the core of the melt, and releasing the gas pressure to allow the core to foam.

Abstract: After molten resin is injected into a mold cavity, an inert gas is sent from an inert gas supply device into the molten resin through a change-over valve and a gas nozzle device so that the molten resin is injection molded. At the same time, a tub is filled with part of the molten resin through a tub communication path. Thereafter, a burr portion of the injection-molded resin is bored using a boring punch so as to make a space within the hollow resin body communicate with the atmosphere. Next, the change-over valve is switched to send a cooling gas from a cooling gas supply device to the hollow space within the hollow resin body so as to cool the injection-molded resin.

Abstract: A method of forming a hollow ceramic article includes the steps of providing a mold having a wall defining a cavity and injecting into the cavity through an inlet through the cavity wall a quantity of a slurry sufficient to fill the cavity. The slurry is formed by a molten thermoplastic binder and ceramic particles suspended in the binder. The portion of the slurry in contact with the cavity wall is cooled to solidify the same, while leaving still molten the portion of the slurry not in contact with the cavity wall. Gas is injected into the cavity through an inlet through the cavity wall and into the still molten slurry portion to force the same out of the cavity through an outlet through the cavity wall. This leaves therein only the gas and a hollow green piece formed from the solidified slurry portion.

Abstract: A method of making a plastic article having an internal conduit for electrical wires including the steps of forming a mold cavity in the shape of the plastic article having a surface area segment defining a passage in the mold cavity, injecting hot liquid plastic into the mold cavity which is quenched by the surface area segment of the mold cavity to form a solidified tubular wall in the passage having liquid plastic therein, injecting gas at the first site in the mold cavity into the liquid plastic in the tubular wall to expel liquid plastic from within the tubular wall so that an elongated gas-filled void is formed within the tubular wall, sustaining the elongated gas-filled void until all of the liquid plastic in the mold cavity solidifies, removing the plastic article from the mold cavity, and opening the elongated voids at opposite ends by drilling or otherwise machining the plastic article to convert the elongated void into an internal conduit for the electrical wires.

Abstract: An injection apparatus capable of carrying out injection and filling of a resin and injection of a gas making use of an injection screw or injection plunger for the injection of a high-pressure gas comprises an injection screw 5 having a conical injection head 3 at the front end thereof and a ring valve 4 around a rear portion of the injection head, an injection cylinder the interior of a front end portion of which equipped with a nozzle member is formed as a tapered surface in accordance with the injection head 3 and can be closed by its contact with the injection head 3 and which contains the injection screw 5, gas flow passages 12 and 8 provided from the front end of the injection head 3 to a rear end portion of the injection screw 5, an opening/closing pin 17 inserted into the gas flow passage 12 in the injection head in such a manner that it can move together with a piston at the rear end of the injection head, and an actuation gas flow passage 10, provided inside the gas flow passage 8, for applying pre

Abstract: An improved gas injection nozzle for use in gas-assisted injection molding process is disclosed. The improved gas injection nozzle comprises: (a) a nozzle body, and a nozzle cap fixedly connected to the nozzle body; (b) a gas inlet provided in the nozzle body so as to allow gas to be injected into a mold cavity via a gas channel formed inside both the nozzle body and the nozzle cap; (c) a heating coil provided on the gas injection nozzle; and (d) at least one circumferential groove formed on the outer surface of the nozzle cap. The circumferential groove formed on the outer surface of the nozzle cap preferably has the shape of a spiral groove, with a depth between about 0.2 mm and about 0.5 mm and a length between about 50 mm and about 150 mm. The combination of the heating coil and the circumferential groove prevents the formation of micro cracks that are often formed in the interstices between the nozzle cap and the sprue bushing during the cooling stage of injection molding process.

Abstract: A compression apparatus which is operated in association with at least two mold parts which can move relative to one another. The compression apparatus is formed of at least one compression units having a working chamber and a working element which can move in it. A gaseous medium can be provided to the working chamber under any initial pressure. During the closing motion of the parts of the mold, the working element is moved in the working chamber, such that the volume in the working chamber is reduced, and in this way, in the course of the closing motion, the gaseous medium is compressed in the working chamber. The compressed gaseous medium can then be sent to a consumer with or without intermediate storage. A compression apparatus of this type is intended for an injection molding machine in which gas pressurization is to take place in a cavity.

Abstract: A method and an apparatus are disclosed for producing plastic objects with solid regions and hollow regions. The method has the following steps: a) blocking off a part of the cavity (2) of a molding tool (1), so that little or no plastic melt can reach the blocked-off region (8); b) injecting plastic melt into the unblocked region (9) of the cavity (2) of the molding tool (1); c) releasing the blockage, so that plastic melt can reach the previously blocked-off region (8) of the cavity (2); d) injecting a pressurized gas into the melt by means of at least one fluid injection nozzle (7), so that the melt injected into the molding tool is distributed into the desired regions of the cavity (2) while forming a hollow space and is pressed against the cavity walls of the molding tool (1); e) allowing the molded part (6) to cool; f) relieving the cavity (2) of the pressure of the pressurized fluid; and g) demolding the molded part.

Abstract: Disclosed is a hollow, resin mechanical part having a shaft integrally formed therewith, comprising a hollow, integral, functional segment-shaft structure comprising at least one functional resin segment, and a resin shaft coaxially, integrally formed with the functional segment, wherein the integral segment-shaft structure satisfies the relationships defined by the following formula 0.9.ltoreq.L(b)/L(a).ltoreq.1, in which L(a) represents the entire length of the integral segment-shaft structure, and L(b) represents the length of the hollow. The mechanical part of the present invention has not only high dimensional precision and excellent material-recycling characteristics, but also can be produced with high productivity, and is very useful in various fields, such as automobiles, ordinary machinery, precision machinery and electric and electronic equipment.

Abstract: The production of an injection moulding of plastics material that includes introducing a supply of plastics material through one or more openings in a mould space, and introducing by way of at least one gas supply passage, a pressurized gas through a separate opening in the mould space into the plastics material within the mould space whereby the gas creates a gas containing cavity in the plastics material. An opening and closing of the gas supply passage is controlled by a valve which is opened by the pressurized gas with the valve featuring a valve port at the outlet end of the gas passage, and a movable valve member extending longitudinally of the gas passage for opening and closing the valve port. The valve member at least when in its extended or valve port open position, protrudes into the mould space and penetrates the plastics material to assist the gas in entering the plastics material.

Abstract: A method and an apparatus for producing plastic objects with hollow spaces is disclosed. The method comprises the following steps: establishing a fluid connection (9) between the main cavity (2) of a mold (1) and an overflow cavity (8) and injecting a sufficient amount of plastic melt into the cavity (2) of the mold (1) along a melt flow path, which extends from a plasticizing unit (4, 5) through a plastic injection nozzle (3) into the mold (1), such that plastic melt passes from the main cavity (2) into the overflow cavity (8). The fluidic connection (9) between the main cavity (2) and the overflow cavity (8) is then broken-off prior to the introduction of a pressurized fluid, especially a pressurized gas, into the melt in the cavity (2) by means of at least one fluid injection nozzle (7), so that the melt situated in the cavity (2) is distributed in the cavity (2) while forming a hollow space, and is pressed against the cavity walls of the mold (1).

Abstract: A method and an apparatus for producing plastic objects with hollow spaces is disclosed. The method comprises the following steps: injecting a sufficient amount of plastic melt into the cavity (2) of the molding tool (1); simultaneously and/or subsequently injecting a pressurized fluid into the melt by means of a fluid injection nozzle (7); allowing the molded part (6) to cool; relieving the cavity (2) of the pressure of the compressed fluid, and demolding the molded part, while plastic melt is driven out into at least one overflow cavity (8), which is connected to the cavity (2). According to the invention, the volume of the overflow cavity (8) is changed, and in particular enlarged. This volume increase advantageously is controlled or regulated. The advantage achieved thereby is that the injection molding cycle, especially the overflow of melt into the overflow cavity (8), remains controllable by simple means.

Abstract: The invention relates to a process of and an apparatus for injection molding hollow-blown plastic bodies in which a mold cavity formed by a tool and consisting of at least one main mold cavity and at least one side mold cavity connected with this is filled with a pressurized flowable plastic melt and, simultaneously or after the setting in of the hardening of the walls in the main mold cavity, a pressurized fluid is introduced into the main mold cavity, as a result of which the flowable core in the main molded cavity is displaced while forming a flow front and, as soon as the flow front has reached the point of connection to the side mold cavity, a pressurized fluid is additionally introduced into the side mold cavity at the side opposite the point of connection such that the molten core in the side mold cavity is forced out together with the molten core in the main mold cavity.

Abstract: A cover unit is constituted such that a conductive member is provided on the entirety of the inner wall of a hollow cover, and the periphery of the conductive member is fixed to the cover.

Abstract: A method of manufacturing a functional hollow structural member having a structural member having a hollow part, and functional means disposed on the inside surface of the hollow part, comprising the steps of injecting a molding material into a molding die, injecting a gas and a functional substance into the molding material to form a hollow part in the molding material, forming functional means inside of the hollow part, and forming a structural member by solidifying the molding material. As the functional means, a layer having a magnetic function, conductive function, or antibacterial function is used.

Abstract: A gas-introduced injection molding is disclosed, which is obtained by charging molten resin into a die and introducing gas into the charged molten resin. The molding thus obtained has a sufficient thickness portion extending linearly as a framework and a sheet-like small thickness portion integral with the sufficient thickness portion and having a uniform thickness, a space being formed inside the sufficient thickness portion. Thus, even by reducing the overall thickness of the molding it is possible to ensure sufficient rigidity with the hollow portion, and the molding is thus best suited as a sheet-like product requiring a predetermined rigidity, such as an automobile bumper, a household electric product casing, etc.

Abstract: The proposal is for a device for injection molding plastic items enclosing hollow spaces with which a further pressurised medium like air, gas or a fluid can be introduced through a hollow needle (5) at a point differing from the nozzle into a mould (1), the mould hollow or cavity (4) of which can be filled with molten pastic through a nozzle. There is a needle core (9) which can be moved axially to a limited extent in the hollow needle (5) and it is possible via this needle core (9) to vary the cross-section of or open and close the aperture (16) of the hollow needle (6) opening into the mould hollow or cavity (4). The needle core (9) bears a thickened head or plate (10) in front of the end of the aperture in the hollow needle, the outside diameter of which corresponds at least approximately to the outside diameter of the hollow needle, so that it forms, with the aperture end (6) of the hollow needle (5), a radially directed splitting valve.

Abstract: The invention comprises a plasticating machine for the working and forcing of plastic material into a mold, said machine including an elongated housing having a first or proximal end and a second or distal end, an elongated screw shaft with a screw flight therearound, the screw shaft being rotatably supported in the elongated housing, for the working of plastic between the screw shaft and the elongated housing with at least one delivery conduit generally longitudinally arranged through the screw shaft, from a proximal end to a distal tip end thereof. The conduit may be arranged to be movable with respect to the screw shaft to permit delivery of a medium through the screw shaft to any plastic being driven from the machine. The medium may be any single or combination of components selected from the group comprising vapor, liquid, gas, powder or solid, to control the machine or treat any plastic being driven therefrom.

Abstract: A method is disclosed for the production of a molded article, using a mold assembly including a mold having a cavity, for producing a molded article from a thermoplastic resin; an insert block formed of ceramic or glass having a thermal conductivity of 2.times.10.sup.-2 cal/cm.sec..degree.C. or less, the insert block being disposed inside the mold, constituting part of the cavity, and having a thickness of 0.5 mm to 10 mm; and a cover plate for covering a peripheral portion of the insert block. The cover plate is attached to the mold and constitutes part of the cavity, wherein a clearance between the insert block and the cover plate is 0.001 mm to 0.03 mm, an amount of overlapping of the insert block and the cover plate is at least 0.1 mm. The method includes filling a molten thermoplastic resin in the cavity, and then cooling the thermoplastic resin to solidness.

Abstract: A method of injection molding for use with an injection molding machine includes: a) generating pressurized gas and pressurized moisture within molten plastic as plastic pellets are plasticized in the injection molding machine, the pressurized gas and the pressurized moisture having a total pressure defining an internal counterpressure within the molten plastic; (b) pressuring air within a cavity of a mold in the injection molding machine to an air pressure level which is substantially equal to the internal counterpressure in order to counterbalance the internal counterpressure as the molten plastic is injected into the cavity, thus providing a substantially pressure balanced molding environment for the plastic; and (c) maintaining the air pressure level in the cavity substantially constant as the molten plastic is injected into the cavity.

Abstract: A supply of pressurized gas is separated into a first quantity of pressurized gas at a first temperature and a second quantity of pressurized gas at a second lower temperature. The first and second quantities of gas are injected into molten plastic in an injection mold in a predetermined sequence to form a hollow molded plastic article. A controller independently controls the pressure and time of delivery of the first and second quantities of pressurized gas supplied to the mold. A third quantity of extremely lower temperature gas may also be supplied to the mold in a timed sequence with the first and second quantities of gas. A variable pressure regulator receives stored pressure signals from the controller and establishes the pressures of the first, second and the optional third quantities of gas independent of each other.

Abstract: A gas assisted injection molding system and method in which quantity of an inert gas is applied both internally and externally to a thermoplastic material introduced into an injection mold cavity during formation of an injection molded part. The system includes first and second mold portions defining a mold cavity. An injection means injects a quantity of a thermoplastic material into the mold cavity to form an injection molded part within the cavity. At least one internal gas inlet is provided for introducing a first quantity of gas into a portion the thermoplastic material to form a gas channel therein. The gas within the gas channel presses the thermoplastic material against a mold parting line defined by the intersection of the mold portions and forms a seal between the mold cavity and the mold parting line.

Abstract: A method of injection molding for use with an injection molding machine (10) includes: (a) generating pressurized gas and pressurized moisture within molten plastic as plastic pellets are plasticized in the injection molding machine (10), the pressurized gas and the pressurized moisture having a total pressure defining an internal counterpressure within the molten plastic; (b) pressuring air within a cavity (30) of a mold (22) in the injection molding machine (10) to an air pressure level which is substantially equal to the internal counterpressure in order to counterbalance the internal counterpressure as the molten plastic is injected into the cavity (30), thus providing a substantially pressure balanced molding environment for the plastic; and (c) maintaining the air pressure level in the cavity (30) substantially constant as the molten plastic is injected into the cavity (30).

Abstract: A control system for a gas assisted injection molding apparatus which provides precise and reproducible indication of when the injection of plastic is to terminate and when the pressurized gas is to be introduced on the basis of sensing of the location of the flow front of the injected plastic in the mold cavity. The flow front sensor control system according to the present invention includes: one or more sensors located at one or more predetermined locations of the cavity of a mold of a gas assisted injection molding apparatus, a controller which processes sensed data from the one or more sensors and thereupon sends a signal to the gas assisted plastic inaction molding apparatus to discontinue plastic inaction and introduce pressurized gas. The preferred type of sensor is a temperature sensor; however, other types of sensors, such as a pressure sensor, may be used.

Abstract: An apparatus and method includes a mold which defines a mold cavity with an inlet through which a molten, moldable material can pass into and/or through the mold cavity. A feeder for preparing the molten, moldable material, is spaced from the mold and expels the material to the mold cavity or to an accumulator connected to the mold cavity. A mechanism for controlling the temperature of the material in the feeder, accumulator, and the mold, as well as at least one gas injection unit with controls for the gas before, during and after its injection into the mold cavity and/or into gas channels located within and/or around the mold cavity are provided. A closed loop regulating system easily adjusts and regulates the gas flow and monitors the average gas pressure of the injected gas according to a programmed conditioning signal. The gas injection unit has relief valves and gas tanks.

Abstract: A method for the production of a molded article having a hollow portion by utilizing a gas compression apparatus having a gas source, a compressor composed of a piston and a cylinder, and a discharge valve for controlling the flow of pressurized gas discharged from the cylinder, the method comprising introducing the pressurized gas through the discharge valve into a molten resin injected into a cavity of a mold, under the control of the discharge valve while carrying out, in one molding cycle, the intake step of supplying gas from the gas source to the cylinder and the compression step of compressing the gas by movement of the piston in the cylinder, at least twice each on the basis of predetermined compressor operation conditions, and thereby forming the hollow portion in the molded article.

Abstract: A composite legal type bicycle frame is disclosed which contains a front frame portion and a rear frame portion. The front frame portion contains a central main and a plurality of legs for connecting the central main with various components of the bicycle, and the rear frame portion contains a rear fork, which consists of a left rear branch and a right rear branch. The left and right rear branches are first cured and glued together at respective abutting surfaces thereof to form an integral rear fork before they are adjoined with the front frame portion, via prepregs and using a cocuring procedure. The left and right rear branches are formed to contain cross-shaped matching protrusion and recess, respectively, on the abutting surfaces thereof, so as to enhance the integrity of the integral rear fork. As a result, a great flexibility of design options can be obtained. For example, the rear fork can be connected to one of the legs but not to the central main.

Abstract: The present invention comprises a method for delivering a medium such as a gas, vapor or liquid into a melted plastic in a mold via an elongated screw shaft rotatably supported in a housing, the method including the steps of providing the screw shaft with a bore longitudinally therethrough from a proximal end to a distal tip end thereof, rotating the screw shaft in the housing to move plastic therethrough, and into the mold, introducing a gas, vapor or liquid into the bore, to permit the gas, vapor or liquid to be delivered through the bore, and into the molten plastic in the mold through the distal tip end of the screw shaft.

Abstract: In the molding of boot and shoe heels a foamable plastics molding material is injected into a heel mold and a pressurized gaseous fluid is injected into the heel body after it has formed an outer skin against the mold inner surfaces but before it has fully set in order to displace and compress the foaming material and form within the heel at least one enclosed hollow chamber which provides a different degree of resilience to heel strike forces at the location of the chamber. A plurality of closely adjacent chambers may be provided to obtain the same effect, particularly when the heel is shallow. A preformed member may be placed in the mold to form the heel outer surface and ensure a minimum heel wall thickness at this location. The invention also includes apparatus for making such heels, and the heels when so made. The molded body may comprise a sole with an integral heel part. The enclosed chamber may be vented to the ambient atmosphere or it may be sealed.

Abstract: A method of injection molding for use with an injection molding machine includes: (a) generating pressurized gas and pressurized moisture within molten plastic as plastic pellets are plasticized in the injection molding machine, the pressurized gas and the pressurized moisture having a total pressure defining an internal counterpressure within the molten plastic; (b) pressuring air within a cavity of a mold in the injection molding machine to an air pressure level which is substantially equal to the internal counterpressure in order to counterbalance the internal counterpressure as the molten plastic is injected into the cavity, thus providing a substantially pressure balanced molding environment for the plastic; and (c) maintaining the air pressure level in the cavity substantially constant as the molten plastic is injected into the cavity.

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.