Abstract: The present invention relates to a method and the relative device for the effecting thereof, for eliminating the feeder head portion which results at the end of the injection moulding process for articles of thermoplastic material.

Abstract: This disclosure is concerned with a process for molding polyethylene terephthalate at a reduced mold temperature, i.e., less than 120.degree. C., and still obtaining crystalline parts by incorporating a small amount of a two phase polyacrylate comprised of a cross-linked elastomeric first phase to which a rigid thermoplastic second phase has been grafted. It is also concerned with a glass reinforced polyethylene terephthalate especially suitable for molding into colder molds which contain this two phase polyacrylate.

Abstract: A plunger injection molding machine for utilizing a liquid composition and in addition to the other usual features, a valve for allowing liquid composition to enter a barrel means; sealing means on the plunger which operates on the barrel of the machine so as not to allow the liquid composition to leak pass the sealing means out of the rear of the barrel means; and stop means to regulate or control the rear work movement of the plunger means out of the barrel means which results in accurate control of the amount of liquid composition forced into the mold. A preferable composition for use with this type of machine is a silicone composition and more specifically a SiH olefin platinum catalyst silicone composition.

Abstract: An apparatus for molding information discs includes a pair of mold plates, at least one of which is movable toward and away from the other, and adapted to form a mold cavity therebetween, a center hole forming pin slidably mounted in one of the mold plates and a center plate in the other mold plate in alignment with the center hole forming pin. The center hole forming pin has a recess in its end which faces the center plate and a plurality of passages extending substantially radially therethrough from the recess to the outer surface thereof. The passages allow the flow of mold material therethrough as the center hole forming pin is moved through the mold material in the forming of the center hole to reduce the force necessary to move the pin through the mold material.

Abstract: Glass fiber reinforced thermoplastic resins comprising glass fiber, a thermoplastic resin and a copolymer of an ethylenically-unsaturated monomer and from about 1 to about 20 wt. % of copolymerizable functional monomer exhibit a marked improvement in impact properties when melt processed in screw-fed melt processing equipment such as a screw-fed injection molding machine using back-pressures in the range 0-100 psi.

Abstract: A mold apparatus which in addition to the other mold elements, has shuttle plate means adjacent to the nozzle means out of which the molding composition comes out of into the mold cavity, which shuttle plate means forms part of the mold cavity. The shuttle plate means are adapted to automatically take a finished molded part from the mold and remove it out of the mold apparatus. At the same time while the molded part is being taken out of one portion of the shuttle plate means, the other part of the shuttle plate means is being utilized to form a molded part.

Abstract: The invention relates to a process for repairing hot refractory linings by applying a refractory composition by spraying on to the part of the lining to be repaired. The invention resides in the improvement comprising applying a composition containing an effective amount of combustible elongated channel-forming elements substantially evenly distributed throughout the composition.

Abstract: An apparatus and method for making a hearth of kiln under vibration comprising mounting vibrating mechanisms to a pressurizing plate in which the area of the pressurizing surface is in the range 0.5-5 m.sup.2, and said vibrating mechanisms are mounted to the pressurizing plate directly or through a frame.

Abstract: A method of molding an element from liquid synthetic resin wherein liquid resin is introduced into a mold cavity through a first gate and liquid resin is concurrently introduced into the mold cavity through a second gate with portions of the resin received through each of the gates meeting at a joint interface. The resin in the second gate is caused to solidify sooner than the resin in the first gate so that the leading surface of the resin received through the first gate projects into a leading surface portion of the resin received through the second gate during the mold packing operation to provide an enlarged weld line area and improved strength in the joint. Apparatus for carrying out this method includes structure for causing the temperature in the gate of one of the resin streams to be different from that of the temperature in the gate of the other of the resin streams as a result of preselected characteristics of the respective gates through which the resin streams are passed.

Abstract: A portable apparatus for reforming plastic pipe ends is disclosed. The apparatus includes a heat sink clamp and depth collar for locating said clamp a predetermined distance from the end of the plastic pipe end. This heat sink clamp substantially limits axial heat penetration from an oven into the plastic pipe so as to permit the reshaping of the pipe end into a sanitary flow end, i.e. an end having imperfection-free contours.

Abstract: The method and apparatus for the injection of an injection material into a mold includes an upright extruder mechanism having an upright feed screw driven from its lower end. Material introduced at the top of the extruder is fed by the screw outwardly of the extruder through an outlet projected laterally outwardly from the extruder at a position adjacent the lower end of the screw. The extruder outlet constitutes a piston receivable with a cylindrical material chamber of an injection nozzle unit. Material is fed in one direction in incremental amounts from the extruder and into the material chamber when the extruder is moved in one direction relative to the injection nozzle unit, and is then forced from the material chamber by the extruder outlet and into the nozzle unit for injection into a mold when the extruder is moved in an opposite direction relative to the nozzle unit.

Abstract: A center plate for an apparatus for molding recorded discs is disclosed which includes a cylindrical body having an internal recess and a plug secured across the bottom end of the recess. The plug has a pair of passages therethrough opening into the internal recess. An adapter is secured to the plug. The adapter has a pair of ports and a separate universal connection between each of the ports and a separate one of the passages in the plug. This provides for a flow of a heat control medium through the center plate and permits ease of connecting pipes to the ports to provide the flow of the heat control medium.

Abstract: An arrangement for loading an injection unit of an injection molding machine by a stuffer apparatus wherein a uniform measure of plastic-like material is consecutively fed to the machine. The arrangement comprises a plurality of container units which are movable from a receiving position under a hopper to a discharge position over the injection unit of the injection molding machine wherein the material is rammed therein. As one of the container units is being emptied into the machine, another container unit may be filled, reducing time between successive loadings and unloadings thereof.

Abstract: A video disc member is described having a uniform value of birefringence over the entire information storage surface of the disc. This value of birefringence is the same at the inner information storage radius as at the outer information storage radius. The preferable composition of the video disc is a specially prepared polymethylmethacrylate, referred to as PMMA. The method of molding the improved video disc member includes an extended drying time for said composition and increasing the melting temperature. The increase in melt temperature provides a low and uniform value of birefringence. The improved drying cycle eliminates splay marks, blisters and other surface imperfections as compared to manufacturer recommended drying times.

Abstract: Disclosed herein is a mechanical expansion plug for the internal calibration of plastic material tubes in general, particularly for fashioning the seats for gaskets, that comprises a tubular extending body provided, along the lateral surface thereof, with a circumferential aperture. Inside the said body, able to slide in the two directions coaxially thereto and without the possibility of one rotating with respect to the other, there is a movable element of truncated cone conformation, provided peripherally with a first and second set of equidistant guides that extend along generatrices of the said element and alternate one with the other.

Abstract: A method and device for manufacturing a record carrier is disclosed in which a liquid moulding resin is deposited in a cavity formed in the surface of a mould which also has at least one data track. Thereafter a flexible substrate, having a central projection, is deformed into a convex shape and is pressed against the moulding resin. As the projection on the substrate enters the mating cavity in the mold, the resin is squeezed out of the cavity and rolled out across the mould surface by the substrate which is flattened into a planar form during the pressing step. The moulding resin is then cured and the assembly of the substrate with attached, cured resin layer is removed from the mould.

Abstract: A socket of a thermoplastic pipe is provided with an internal groove by subjecting the tube to an upsetting action and simultaneously inflating the tube by an inner pressure. Subsequently a moulding ring is expanded and the tube is shrunk onto the expanded ring by cooling. Before shrinkage the inner diameter of the bottom of the groove is at least equal and preferably greater than the outer diameter of the moulding ring in expanded form.

Abstract: A hot sprue valve assembly is provided for controlling flow of molten material into the mold cavity 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. The valve assembly includes a hot sprue bushing defining a heated flow path for passage of molten material toward a stationary dispersion head positioned centrally within the mold cavity. The dispersion head directs the molten material to flow in a generally radially outward direction with substantially uniform radial distribution into the mold cavity.

Abstract: A bottom in a tube having an open end is formed by heating the tube and a supporting mandrel and advancing a sleeve over the end of the tube which flares outwardly after heating so as to collapse the flared end. The collapsed end of the tube is closed by contacting the collapsed end with a mold which cooperates with the sleeve to form the bottom.

Abstract: This relates to the increasing of the intrinsic viscosity of resins, particularly PET, by effecting a solid state polymerization of the resin. More particularly, the solid stating is effected in conjunction with an injection or extrusion unit wherein after having the IV of the resin increased, the heated resin may be fed dry into an injection unit thereby utilizing the heat of the heated resin to reduce heating cost. The solid state polymerization is effected by heating the resin in the presence of either a vacuum or an inert gas such as nitrogen.