Abstract: A hot sprue valve assembly is provided for controlling flow of molten material through a hot sprue bushing of an injection molding machine. The valve assembly is particularly designed for use with an injection molding machine for molding centrally apertured record discs, such as video information discs, and the valve assembly includes means for forming the central aperture in the disc. In one embodiment, the aperture-forming means comprises a sleeve valve for molding the aperture in the disc prior to solidification of the disc-forming melt, whereas in another embodiment the aperture-forming means comprises a punch for punching the aperture subsequent to solidification of the disc-forming melt.

Abstract: A method for fabricating a plastic electrical insulator having a fiberglass-reinforced plastic core rod and a plurality of insulator discs disposed thereon. The insulator discs are formed of a plastic molding compound which is especially suited for outdoor use. In accordance with the invention, the insulator rod is disposed in, and passes through, a mold which, when closed, is filled with the plastic molding compound for forming the insulator discs. The separation plane of the mold is situated near the outermost edge of each disc. Subsequent insulator discs are individually formed so as to partially overlap a previously molded insulator disc.

Abstract: This invention relates to a molding apparatus capable of producing flashless molded parts due to a perfect surface-to-surface mating of a pair of molds. The molding apparatus comprises an upper holding means for holding at least one upper mold having a path in which a moldable material is passable, and a lower holding means for holding at least one lower mold having a cavity, wherein a certain amount of fluid substance is filled between a bottom surface of the lower mold and the lower holding means, thereby the lower mold being floatable on the fluid substance and movable along the lower holding means, subsequently a joint between the upper mold bottom surface and the lower mold top surface being realized perfectly due to a back pressure of the fluid substance.

Abstract: An apparatus is provided for precision forming plastic insoles for use in the mass production of shoes. An injection mold structure is shown and a method of assembling the finished insole together with a unit sole structure is described.

Abstract: An expandable member is disclosed that includes a molded body of elastomeric material with a core embedded therein. At least a portion of the core is not bonded to the body. A fluid conduit is provided through which fluid can be injected between the core and the unattached portion of the body to move the core and the unattached portion apart and expand the member.

Abstract: A process is provided for forming a self-supporting semiconductor film or ribbon. A TESS substrate is prepared from a substrate of refractory material having an expansion coefficient different from the expansion coefficient of the semiconductor material. A colloidal suspension of graphite is applied to the substrate to form a thin layer of loosely adherent graphite particles. Over this layer of graphite is deposited a layer of the semiconductor material, the deposition occurring at an elevated temperature. Upon cooling from the deposition temperature, the differential thermal expansion coefficience causes the shearing at the graphite layer and therefore provides for the easy removal of the semiconductor layer from the substrate.

Abstract: The apparatus of the present invention includes a stationary assembly and a movable assembly. The stationary assembly is comprised of a stationary platen which has a heat plate, a temperature-controlled sprue bushing and a mold face positioned thereon. The movable assembly is comprised of a movable platen which has a heat plate mounted thereon and a mold face, corresponding to, and adapted to be aligned with, the mold face on the stationary assembly to form a partially open mold cavity. Means are provided to feed a supply of thermosetting molding material through the sprue bushing into the partially open mold cavity. Means are provided to completely close the mold cavity and place the apparatus in a compression stage.

Abstract: The apparatus of the present invention includes a stationary assembly and a movable assembly. The stationary assembly is comprised of a stationary platen which has a heat plate mounted thereon, a temperature-controlled sprue bushing mounted in the heat plate and a plurality of mold faces positioned on the heat plate surrounding the periphery of the sprue bushing. The movable assembly is comprised of a movable platen which has a heat plate mounted thereon and a plurality of mold faces, corresponding to, and adapted to be aligned with, the mold faces on the stationary assembly. Means are provided to move the movable assembly into close proximity with the stationary assembly to form partially open mold cavities. Means are provided to feed a supply of thermosetting molding material through the sprue bushing into a manifold area and into the partially open mold cavities. Means are provided to completely close the mold cavities and place the apparatus in a compression stage.

Abstract: Raw material of less than 10% of the one injection amount is heated at a time to a high temperature just before injected into the mold cavity by an intermittent heater and is injected continuously into the cavity keeping that temperature. Heat capacity of the heater is small to obtain quick response and to give no heat effect to the raw material to be injected for the next product. The device of this invention comprises a device to inject a predetermined amount of raw material for one injection intermittently, a flow path for the raw material which connects said device and the mold, and electric resistant heater in the flow path to generate Joule heat and to transfer the generated heat to the raw material flowing through said flow path.

Abstract: Method for molding articles from agglomerated particles utilizes a press and a plurality of molds mounted to circulate in a closed path. After the pressing step a mold is aligned at one end of a row of molds, the row is placed under pressure and the articles therewithin caused to set. Simultaneously a mold is withdrawn from the other end of the row. The latter mold is then emptied, and the emptied mold returned to the press. The aligned molds are fastened together during the setting step. The invention includes apparatus for carrying out this process.

Abstract: A thermoplastic socket pipe part with a sealing member comprising a sealing head and sealing sleeve, the sealing head being retained by means of a retaining ring, which retaining ring is formed by bending back the end part of an extruded plastic tube provided with three widenings with decreasing inner diameter as seen from the free end of the plastic tube.

Abstract: An annular flow plastic extrusion nozzle or gate is provided with a torpedo to heat the plastic to be extruded through the gate. A passage is provided around the torpedo and the torpedo has a flattened end in the parting line of the mold. An annular opening is provided around the base of the torpedo in the nozzle or gate housing. A conical recess is provided in the flat end of the torpedo to receive a correspondingly shaped male extension of a shaft or core pin removably mounted in a portion of the mold. A hub cavity in that portion of the mold may be provided around the end of the pin and mold cavities extend therefrom as desired to form propellers or impellers or rotors of the desired configuration. Discharge of the flowable plastic through the 360.degree.

Abstract: A method of making a curved-tip (coude) catheter which comprises: inserting an end of a flexible, thermoplastic tube into the bore of a closed-end, hollow, tubular die which defines the desired curve of the curved-tip catheter. The tubular die is heated to a temperature above the plastic melt temperature of the thermoplastic tube, while advancing the tube into the die, to cause at least about 0.5 cm. of the tube end to collapse into a generally solid, curved mass. The die and tube contained therein are then cooled to a temperature below the plastic melt temperature, and the tube is withdrawn having a closed, formed coude tip.

Abstract: A method of dispersing glass fibers in a rubber solution comprises forming a rubber-bonded glass sheet and dissolving the rubberbond of the glass sheet in a rubber solution comprising rubber and a solvent compatible with that used to form the rubber-bonded glass sheet.

Abstract: This invention is a bearing tube for a marine propeller shaft, and a method of making such a tube according to which polyacrylonitrile or other fibres (8) carrying a sticky resin (7) are wound onto a mandrel (5) and, at least at the bearing lining, wear resistant powder (6) or other compound is included with the fibres and resin to improve the properties of the bearing lining. Such a bearing tube including essentially a resin impregnated polyacrylonitrile fibres and the wear resistant compound can be easily machined to size without any health hazards, and can be lubricated by oil or water (even sea water) and is dimensionally stable.

Abstract: A low-pressure screw in-line type injection molding method and apparatus for use with materials such as urea mixed resin powder are disclosed. The initial injection is performed at a converted injection pressure in the range of 250-700 Kg/cm.sup.2 and at an injection velocity in the range of 30-50 mm/sec. when the mold cavity has become nearly completely filled, the converted injection pressure is lowered to 50-200 Kg/cm.sup.2 for the completion of the injection cycle under low pressure conditions.

Abstract: There is disclosed an improved molding machine and a system for utilizing said machine, wherein central sources of supply are used to provide the operating requirements for the machine, such as high pressure hydraulic fluid, compressed air, cooling water and electic power. The machine disclosed utilizes a stationary platen and a movable platen, with a novel mold clamping arrangement as an integral part of the movable platen assembly. In this regard, said movable platen includes a pair of relatively movable plate members, with a high pressure diaphragm interposed therebetween. On the rearward most plate member there is mounted latching means for fixing the position of said rearward plate member preparatory to pressurizing of the diaphragm. When pressurized, the diaphragm will force the forward most plate member toward the stationary platen to effect the desired preloading of the mold inserts carried by said platens.

Abstract: An injection molding apparatus is disclosed which includes a screw having a multichannel wave screw section. In the wave screw section, a helical passage defined by a radially extending helical screw flight is divided into a pair of flow channels by a radially extending helical barrier. The helical barrier is radially shorter than the helical conveying flight and the effective outer width thereof is axially narrower than the helical conveying flight. Each flow channel is provided with an undulating base surface that defines a plurality of wave cycles. The base surface varies in a radial direction between a valley portion and a crest portion for the wave cycle and a wave cycle is defined as extending between consecutive crest portions. The crest portions of one flow channel are helically displaced from the crest portions of the adjacent flow channel.

Abstract: Two roller elements are spatially related so that grooves therein are aligned to define an opening between the roller elements. The grooves have pluralities of cavities formed therein into which material from a line is squeezed as the line is passed through the opening so that protuberances are formed on the line. A heating element is provided to soften the line prior to having the protuberances formed, and a cooling chamber is provided to cool the line after the protuberances have been formed.

Abstract: A method and apparatus for virtually eliminating the web-like "jetting" lines on finished injection molded products by utilizing an expandable cavity which is initially set at a reduced or minimum size to intercept resin flow and disperse it as it enters the cavity, the resin being maintained under pressure within the partially filled cavity, wherein the cavity expands under pressure of the resin flowing therein until the finished size of the end-product is attained.