Abstract: An injection mold with locking device comprises a fixed backing plate and a fixed mold part plate which are connected to each other by four tie rods. A movable mold part plate is connected to the fixed backing plate through a drive and locking mechanism which is capable of moving the movable mold part plate into a mold position with the fixed mold part plate. A thermal force control apparatus is associated with one or more of the tie rods for changing the temperature of the tie rods and thereby causing the tie rods either to expand or contract. By such expansion or contraction, the exact force applied between the fixed and movable mold part plates can be adjusted to a desired level.

Abstract: Apparatus for injection moulding thermoplastic material is disclosed wherein a heavy-duty sprue bush is heated along a substantial portion of its length to keep the thermoplastic material from solidifying during interruptions in the moulding cycle. The apparatus provides for minimal contact between the heated sprue bush and the moulding die to prevent heat transfer between them. This is achieved by maintaining an air gap between the bush and the die except at points where the thermoplastic material passes into the moulding cavity. Sprue runners oriented generally parallel to the mould joint line are aligned with cavity injection openings which are similarly oriented. These injection openings pass through a thin wall of the mould that extends generally perpendicularly to the joint line such that when the moulds are open, the sprue is cleanly severed from the moulded article.

Abstract: This invention relates to an edge gated injection molding system. An electrically heated sprue bushing is seated in a well in the cavity plate with a centrally extending melt runner passage which branches radially outward with separate channels leading to a number of edge gates in the cavity plate. An air gap is provided to insulate the hot sprue bushing from the surrounding cooled cavity plate and a hollow seal is provided at each gate to convey the melt across the air gap. Each seal is in alignment with one of the channels and one of the gates, and has its inner end seated in a recess in the sprue bushing and its outer end abutting against the curved wall of the cavity plate. The outer ends of the seals are dome shaped so that they are slightly resiliently deformable. A portion of the wall of the cavity plate is slightly inwardly tapered so that at the gates, the effective combined diameter of the sprue bushing and the seals is slightly larger than that of the well.

Abstract: An apparatus for modifying the between the ribs space in a thermal plastic battery container is disclosed. The apparatus comprises a heated non-circular wiping member which when rotated about a fixed centerline defines a first circumference having a diameter substantially equal in length to the minimum between the ribs space and a second concentric circumference having a diameter greater in length than the first diameter.

Abstract: Method and apparatus for injection moulding of thermoplastic materials in which a screw in a plasticizer acts as an injection ram to inject plasticized material through a heated runner system into a mould. Part of the injected shot of plasticized material is passed into a reservoir communicating with the runner system. Upon completion of the injection of the shot, the passage from the plasticizer is closed by a valve and the screw is returned to plasticizing position while a pressure is applied to the plasticized material in the reservoir to force it into the runner system to apply a positive pressure so that an article is formed in the mold free of sink marks or weak spots. The reservoir may be provided in series with the shot injecting passage from the screw plasticizer by a nozzle on the plasticizer acting as a piston movable in a cylinder communicating with the runner system of the mould, the valve acting to close the plasticizer from the end of the mould.

Abstract: A process whereby the reflective coating of a video disc is applied to the disc directly in the press in which the disc is stamped by the use of fluid organometallic compounds.

Abstract: Adjustment device for the locking jack 9 of a molding press comprising, on a base 1, a mold 4 held by a fixed plate 2 and a movable plate 3 controlled by a rapid movement mechanism 10-13, itself connected to a fixed plate 5 via a movable plate 8 subjected to the action of the locking jack. The adjustment device includes a stem 17 which frictionally slides in relation to the base 1 and which is fitted with arms 18, 19 situated between two control contactors 15 and 16 of the locking jack and connected to the movable plate 8. The device provides automatic adjustment of the control of the locking jack 9 in accordance with the thickness of the mold.

Abstract: A mechanical interlock mechanism for the safety cover of the die closing unit of an injection molding machine which has two arresting rods attached to the movable die carrier frame and extending rearwardly through a stationary cylinder head plate, where pairs of toothed arresting jaws are movable into and out of engagement with toothed surfaces of the arresting rods to block their advance, in response to an opening movement of the safety cover which, through two attached control rods, moves the arresting jaws by means of cam surfaces and cooperating cam followers and drive links.

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. The valve assembly includes a poppet valve movable between an open position to allow flow of molten disc-forming material into a mold cavity, and a closed position to prevent flow of the disc-forming material into the mold cavity. The poppet valve is designed to mold a central aperture in the disc upon movement to the closed position, and the valve assembly is designed to accommodate air ejector apparatus for removing a solidified record disc from the machine.

Abstract: A device for exercising a living hinge of an article and/or closing a lid of a cap while the article or cap is in a mold for forming the article or cap. The device includes a finger which slides between the mold sections, and, in the process, engages a portion of the article or the lid, rotates the portion or lid about the hinge, and in the case of the cap, snaps the lid shut. In an alternate preferred embodiment, when the finger reaches a predetermined point it pivots toward the female mold section to snap the lid tightly shut.

Abstract: This invention concerns a process for fabricating fiber reinforced thermoset resin articles. The process comprises the steps of (a) providing in a distributing zone, an intimate mixture of one or more fibers with a melting point or a glass transition temperature above about 130.degree. C. and a fiber length greater than about 0.5 centimeters, and a liquid resin, said resin having a viscosity of less than about 3000 centipoise at 25.degree. C., (b) injecting said mixture into the cavity of a closed matched metal die mold, thereby filling said cavity with said mixture, (c) heating said mixture so as to cause an exothermic reaction to occur in said mold, and (d) opening said mold and recovering a thermoset fiber reinforced molded article therefrom.

Abstract: A method of molding a hollow, plastic article having ribs extending from its walls comprising the steps of positioning the mold cavity forming members in a closed position to define a mold cavity corresponding to the configuration of the article; injecting molten thermoplastic material into the cavity; allowing the material to cool for a predetermined period of time to permit partial cooling and setting of the plastic; injecting additional plastic material into the rib forming portion of the mold cavity at a plurality of injection points spaced along the rib portion; pausing for a second predetermined time to permit complete setting of the plastic in the mold; displacing the cavity defining members from their closed position and exerting an ejecting pressure on the rib portion at the plurality of injection points along its length to aid in ejecting the article from the mold.

Abstract: A plastic pipe comprises an inner wall and an outer wall, being integral with longitudinal partitions between them and bounding longitudinally extending channels and a circumferential, helically, or non-helically extending groove, which groove has been formed by closing the channels by pressing channel wall parts onto each other. A retaining ring may be snapped into an external groove.

Abstract: A novel method and device for precision injection molding is disclosed providing controlled cooling of a portion of the mold cavity surface during the molding cycle, or several such portions independently, and also, in the preferred embodiment controlled heating of a portion of the mold cavity surface during the molding cycle or several such portions independently, whereby high quality, high precision parts having close dimensional tolerances may be produced. Another aspect of the invention, a volume-controlled variable conductance heat pipe is disclosed, which novel heat pipe comprises housing means forming a sealed chamber, fluid, such as water or ammonia, within the chamber, wicking means and control means for controlling the thermal conductance of the heat pipe comprising means for controlling the volume of fluid in the liquid phase in the chamber.

Abstract: The invention pertains to a valve assembly particularly useful in injection mold apparatus of the type comprising a pair of abutting mold body members having registering cavity portions and channels in their abutting interface surfaces. The valve assembly comprises a generally tubular mounting member and an elongate valve element having a portion mounted within the mounting member for rotation therein and a portion extending axially outwardly from the mounting member. The extending portion of the valve element has an axially directed end face with a recess therein opening axially and radially of the valve element. Detent formations are cooperative between the mounting member and the valve element for retaining the valve element in a desired one of a plurality of positions with respect to the mounting member.

Abstract: An injection molding device for molding shaped bodies of natural or synthetic rubber comprising a heatable mold for shaping and vulcanizing therein the bodies to be molded and an elongated feed duct communicating with the mold via an injection nozzle. Plasticized material is fed into the duct by a plasticizing device and injection is effected by a piston-type injection device, both communicating with the duct. There is provided in the duct a valve which in its closed position blocks ingress of plasticized material into the duct but opens the duct for ingress of the material to be pressed by the injection means into the mold via the nozzle. The valve head is axially displaceable in the duct and mounts a member so dimensioned that in the open position of the valve it fully closes the nozzle opening, thereby pushing any residual plasticized material into the mold and in the closed position is completely withdrawn from the nozzle opening.

Abstract: An apparatus for molding recorded discs includes a pair of opposed mold plates at least one of which is adapted to move toward and away from the other. The mold plates have opposed surfaces which are adapted to form a mold cavity therebetween. A center plate is mounted in each of the mold plates with each center plate having a surface adjacent the opposed surface of the mold plate. One of the center plates has a passage therethrough with a center hole forming pin slidably mounted in the passage. The one center plate has an annular groove in the surface of the passage adjacent the end surface of the center plate. The groove is adapted to receive some of the molding material to form a seal between the center plate and the center hole forming pin and thereby minimize the extent of the formation of flash on the surface of the molded disc.

Abstract: The invention relates to a process for packing, also known as lining, electrometallurgical furnaces.The packing is produced from a concrete which is poured in situ or in precast blocks, composed of a setting cement having a low water retention capacity and low porosity and of an aggregate of which at least a proportion is a carbonaceous product such as anthracite. This packing has a noteworthy resistance to the constituents of fluoride-based igneous electrolysis baths and to liquid aluminum.Application to the packing of igneous electrolysis cells for the production of aluminum.

Abstract: Articles having a relatively smooth and homogeneous surface appearance may be injection molded of thermoplastic rubber on relatively low-injection-speed-and-pressure equipment. To reduce or eliminate the hairy or frosted surface appearance which otherwise commonly occurs, the mold cavity is pressurized with a relatively moisture-free compressed gas before and during a majority of the injection phase of the molding cycle.

Abstract: A single piece plastic shotshell comprising a tube of high density polyethylene which is uniformly biaxially oriented to a substantial degree throughout its length and has side walls of constant internal diameter, thickness, molecular orientation and physical strength, the tube having a substantially thickened integral transverse base section formed of a compressed length of the tube at one of its end portions with a longitudinally extending primer opening therein, the base section being substantially biaxially oriented and telescoped within said end portion of the tube. Apparatus and methods for making the shotshell are also disclosed.