Abstract: A thermal gate for turning on or off the flow of molten molding material into a mold cavity comprises a narrow passage formed by an extremely thin-walled tube of iron-nickel alloy surrounded by a thin sleeve of insulation, this sub-assembly being inserted into a water-cooled mold. When the tube is supplied with electric current, it rapidly heats to a temperature above the melting point of the molding material, permitting such material to flow into the mold cavity. The thin insulating sleeve maintains a temperature gradient across its wall thickness to permit the tube to remain at the desired temperature without undue power input. When it is desired to stop flow of material through the passage, the current is shut off, and the low thermal inertia of the tube and sleeve permit the tube to rapidly transfer its heat to the water-cooled mold, thereby freezing the molding material in the passage.

Abstract: A mold having a concrete base and a mold cavity member lined with sheet metal. Adjacent the sheet metal are electric heating means and between the electric heating means and the concrete base is a light-weight concrete insulating layer.

Abstract: A heater device for tightening a coil on a cylindrical body which forms a passageway between an injector and a mold in an injection molding apparatus. The device has a first anchor for connecting one end of the coil to the cylindrical body, and a second anchor for connecting the second end of the coil to a rotatable ring on the cylindrical body. A threaded portion is arranged on the rotatable ring so that it engages directly with the cylindrical body or with a stationary ring member on the cylindrical body in a manner similar to a worm gear mechanism. Due to the rotation of the threaded member, a force is generated to stretch the coil, thus bringing the coil into positive contact with the surface of the cylindrical body along the entire length of the coil.

Abstract: In a heating device for use in a vulcanizing apparatus in which a green tire is vulcanized by using a metal mold, three magnetic cores around each of which an electromagnetic coil is wound are arranged equidistantly on at least one surface of the metal mold, and a magnetic yoke is arranged on these magnetic cores. Then, three phase alternating currents are respectively supplied to the electromagnetic coils to generate uniform magnetic fluxes passing through portions of the metal mold between adjacent magnetic cores. Therefore, it is possible to obtain the heating device for use in the vulcanizing apparatus which can realize the uniform eddy current distribution i.e. the uniform temperature distribution in the metal mold by a simple construction.

Abstract: A device for the manufacture of molded parts from molding materials, includes a molding tool being completely closed, having a molding cavity formed therein and being divisible, a heating device having two heating plates disposed on top of each other and fastened to the molding tool, the heating plates being in mutual contact along respective contact surfaces thereof, at least one of the contact surfaces having slots formed therein, and tubular electrical heating elements with metal cladding press-fitted in the slots.

Abstract: An alternately heatable and coolable moulding block for manufacturing plate-shaped information carriers from thermoplastic material, which block is composed of a plate of an electrically insulating material which has a thin metal mould containing the information and in which plate a duct for a cooling liquid is provided and of an electrical conductor wound to form a flat induction coil. Between the mould and the insulating plate, there are provided a layer of a material of good thermal conductivity, which layer is in contact with the mould, and a layer of a ferromagnetic material.

Abstract: This invention relates to an improved heated nozzle for injection molding and an improved method of manufacturing it. The nozzle has an elongated body with a melt bore extending generally centrally through it. The cylindrical outer surface of the body has a variable pitched spiral channel extending around it along its length. A helical electric heating element is embedded in the channel to form an integral structure by which the temperature of the hot melt can be maintained within a narrow range as it flows through the bore. The nozzle is manufactured by forming the body with the channel and bore either by investment casting or machining. The heating element is wound in the channel and a bead of nickel brazing paste is run along the top of it. The nozzle is then heated in a vacuum furnace to braze the heating element in the channel. The highly conductive nickel completely covers the heating element and is fused to both the heating element and the walls of the channel.

Abstract: A split mold for multi-component plastics, especially polyurethanes, with venting channels has heating devices in the zone of the said channels to prevent plastic from entering the channels and thus forming flash on the moldings.

Abstract: The invention comprises a method and apparatus to quickly heat a mold cavity surface or portions thereof just prior to the injection of a foamable plastic resin. The apparatus comprises one or more thin metal surface sheets or bands of high electrical resistivity in the mold cavity covering those portions of the mold where a smooth surface finish on the product is desired. In an alternative form the surface sheets may be plated or sprayed metal of high resistivity on a layer of thin electrically non-conducting plastic in turn adhered to the mold cavity surface.The thin metal surface sheet is resistance heated approximately 300.degree. F. in a few seconds or less by a low voltage high current source of electric power just prior to the injection of the foamable plastic. The high current passing through the metal of high resistivity causes conversion of electrical energy into sensible heat very quickly to accomplish quick heating of the mold cavity surface sheet.

Abstract: A method and apparatus for fusing and shaping the end of a rope, cord or the like made of heat fusible fibers avoiding the enlarged or bulbous end which normally occurs when heated in a conventional manner. The method involves inserting the cut end of a rope into a cavity of a member wherein the cavity tapers inwardly in a direction from an open end thereof to a closed bottom end, heating the member to melt the end of the rope thereby fusing together the strands and cooling the heated end of the rope to set the fused ends and shape the same to the internal shape of the cavity. The apparatus is a thin-walled, metallic member conically shaped and located at the end of a handle. A flared sleeve is also provided in which the end of the rope to be fused is inserted to compress the strands together before being heated. The conical member maybe heated by a butane torch or the like or alternatively, an electric resistance heating element maybe incorporated in a stem projecting from the handle.

Abstract: These novel molds are characterized in that they contain a cavity in porous material which is not monolithic, but which, on the contrary, is constituted by zones B with high capillary forces and by zones A with low capillary forces for liquids. The process of using these novel molds is useful for the manufacture of expanded plastics articles.

Abstract: The invention comprises a method to quickly heat a mold cavity surface or portions thereof just prior to the injection of a foamable plastic resin. The apparatus comprises one or more thin metal surface sheets or bands of high electrical resistivity in the mold cavity covering those portions of the mold where a smooth surface finish on the product is desired. In an alternative form the surface sheets may be plated or sprayed metal of high resistivity on a layer of thin electrically non-conducting plastic in turn adhered to the mold cavity surface.The thin metal surface sheet is resistance heated approximately 300.degree. F. in a few seconds or less by a low voltage high current source of electric power just prior to the injection of the foamable plastic. The high current passing through the metal of high resistivity causes conversion of electrical energy into sensible heat very quickly to accomplish quick heating of the mold cavity surface sheet.

Abstract: A conveyor suspension idler mold apparatus for molding a one-piece, elongated, flexible, polymer idler is disclosed along with a method of molding the conveyor idler and the conveyor idler apparatus. A vertical mold has specially shaped cavities for molding the idler without entrapping air, along with shaft positioning and support brackets at each end of the mold for molding a metal shaft into each end of the polymer idler. The shafts positioning and supporting brackets utilize the groove for the bearing retaining ring for locking each shaft into precise position.

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: A method for preparing solid metallurgical mounts uses a surface in heat exchange relationship with mounting molds placed thereon and with an initially liquid mounting agent contained in the molds. The surface is defined by a block of polytetrafluoroethylene exposed to a source of heat. As part of the molding operation, the surface is preheated and maintained at a substantially constant temperature throughout the operation. The molding operation includes mixing of a quantity of epoxy resin and a hardener, pouring the mixture into a mold or molds and curing the mixture at an elevated temperature in contact with the polytetrafluoroethylene surface.

Abstract: Molding apparatus for laminated foam-body panels, comprising first and second walls defining a molding cavity therebetween, the first wall including means for heating the foam during molding and the second wall comprising hingeably mounted access doors, adjustable holding and shaping means for said panels, disposed within the cavity and at least two of which are perpendicularly adjacent, means for simultaneously positioning each of the holding and shaping means, first and second movable locking means for the holding and extrusion means and for the access doors respectively, the first locking means being automatically actuated in response to the positioning means, means for simultaneously actuating and disengaging the first and second locking means, and means for filling the cavity with unmolded foam material.

Abstract: This relates to an injection mold assembly wherein there is a plurality of cavities which are spaced from a center of the mold assembly and wherein each cavity has therein a core so that a thin wall article, such as a preform for a blow molded bottle, may be accurately formed by injection molding. Previously experienced differential in temperature and thus expansion differentials causing core-cavity misalignment are overcome in accordance with this invention by supplying the core retainer plate, which is normally cooler than the cavity retainer plate, with a heater for elevating the temperature thereof as required.

Abstract: A heated mold panel for casting concrete has a rigid base providing a base surface, a substantial part of which is grooved by interconnecting grooves, has a continuous heating element laid in the grooves, and the base surface is covered with a non-porous, non-corrosive material that provides a smooth outside surface covering the base surface, spanning the grooves and enclosing the element in interconnecting passages defined by the grooves and the covering material. Sufficient clearance is provided in said passages around the element for air to flow freely from passage to passage, whereby heat flow from the element to the concrete poured against the outside surface is by radiation from the element and by convection of air flowing in the passages around the element.

Abstract: A toy molding apparatus having a housing or container with a heat source therein surrounded by a heat directing baffle member, at least a portion of the baffle member being configured for receiving a plastic squeeze bottle containing a gelatinous substance therein, the substance being generally solid at room temperature and approaching a liquid state at approximately 105.degree. Fahrenheit. The bottle is positioned within the receptacle for heating by the heat source and upon reaching a fluid state it is poured into a separate mold member to set upon cooling.

Abstract: A heater plate for plunger-type molding presses comprises a plurality of electrically heated heating elements which are inserted into holes through the plate. These holes are disposed in rows parallel to the peripheral outline of the plate so that the density of the heating elements decreases toward the center of the plate. The heating elements are interconnected and also connected to a temperature control device so that the heating elements can be selectively heated whereby the plate can be uniformly heated in spite of higher heat loss at marginal portions of the plate.

Abstract: Apparatus for splicing ends of a sheave insert material in which the ends of a premeasured length of an elastic, thermoset sheave insert material are laminated together in a special splicing jig for fabricating a unitized insert loop, which is subsequently stretched around a sheave into a preformed insert receiving slot along the circumference thereof. The jig holds the ends of the premeasured length of insert material in alignment as a heated mold, included therein, fits snugly around the ends and applies heat to the joint therebetween, into which the insert material, in liquid form, has been inserted to join the ends. The heat thus applied to the joint accelerates the curing of the liquid into the same consistency as the insert; thereby producing a unitized bond between the ends by which the unitized loop is thus formed.

Abstract: This disclosure is directed to a heating device particularly adapted for tire treading and/or retreading matrices and includes a body having a continuously unending channel formed in an exterior peripheral surface of the matrix body in which is disposed an electric or steam heating element having opposite end portions in lapping relationship with the heating element being generally encased in a body of cast metallic material, and means in the form of a generally Z-shaped spacer traversing the channel and separating the solid material encasing the end portions on each other to permit the heating element to expand and/or contract.

Abstract: Apparatus for molding crayons and the like having particular utility in reclamation of broken and worn crayons and molding thereof into new crayons. Means for supplying radiant and convective heat are surrounded by a housing, with a plurality of chutes positioned beneath the heat supply means, each chute having an orifice communicating with a mold cavity into which molten wax flows by gravity. The apparatus has no moving parts and is simple and safe for use by children.

Abstract: A method and apparatus for forming cured polyethylene insulation about high voltage cables by applying uncured polyethylene around a core of the cable. The polyethylene is heated, cured and then cooled to room temperature in a pressurized nitrogen gas atmosphere. In one form the molding apparatus comprises first and second mold forms which define a cavity and which include means for heating the mold halves to the polyethylene curing temperature. Means is also provided to introduce the pressurized nitrogen into the cavity and for subjecting cable portions that extend beyond the mold to pressurized nitrogen until such cable portions are sufficiently cooled to prevent their deformation under pressure, to prevent the oxidation of polyethylene and/or to prevent the formation of voids or enclosures.

Abstract: The two half sections of a battery grid mold are provided with means for cooling the portions of the mold sections directly adjacent the grid cavity and for heating the larger rear portions of the mold sections. The means for cooling the mold sections comprise a plurality of coolant passageways disposed forwardly of the vertical mid-plane of each mold section.

Abstract: Cast panels for building assembly and erection are formed and cured through the use of an apparatus which particularly facilitates high rates of production of such panels and thereby facilitates more economical building construction practices. Fluid materials being cast into panels are received within forms which comprise a cured concrete bed defining a horizontal planar surface maintained at an elevated temperature. Following curing of the fluid materials cast into the forms, stripping of the panels from the form is facilitated by vertically movable side forming members and by bulkheads separating the cured materials into predetermined panel lengths.

Abstract: A multiple use, flexible, elastomeric liner for forms for concrete faced walls prepared by having a series of rigid panels in side by side relation, includes panels of liners for rigid panels having a concrete contacting face of a flexible, elastomeric synthetic polymer used throughout as a negative mold of a desired design in the finished concrete and having an opposed planar surface for face engagement with the form panels. The liner panels will not support the concrete for the wall without the backing panels. The elastomeric liner is a soft, flexible, resilient, elastomeric synthetic polymeric material which permits sharp relief designs having undercuts, and in edge engagement with similar panels squeeze together for a seamless surface in the completed concrete while leaving the impression of itself in exact detail in the hardened concrete.