Abstract: In a molding apparatus employing opposed endless belt conveyors to mold a non-rigid material into a rigid material, the problem of one conveyor being driven at a slightly greater speed than the other conveyor to produce harmful shear stresses within the molded product is avoided by driving both conveyors at generally the same speed during start-up until the rigid product extending between the two conveyors will tend to drive the slower conveyor at the speed of the faster conveyor, at which point the drive for the slower conveyor will be disconnected. One-way clutches may be placed in the drive of both conveyors so that it does not matter which conveyor is slower, or a one-way clutch may be placed in the drive of only one conveyor and the other conveyor constructed so that it will inherently tend to run faster than the one conveyor, or a selectively releasable coupling, such as a clutch, may be placed in the drive of one conveyor so that the drive of the one conveyor may be disconnected.

Abstract: Continuous method and apparatus for treatment of a solid material submerged in a body of liquid wherein the material is sticky and/or has weak tensile strength. The material is supported, while it is so submerged, by a dynamic layer of the liquid lying between the material and a moving surface. The method is illustrated by heating and thereby foaming a strip of heat foamable thermoplastic resin while it is held submerged in a denser heat transfer liquid by a dynamic layer of that liquid generated by a moving belt above the foaming material. In an example, expandable high density polyethylene strip is foamed continuously while it is so held submerged in molten salt.

Abstract: An apparatus is disclosed for making foam plastic insulating panels. The apparatus has a lower conveyor band forming a support surface and a first continuous form belt on the support surface and an upper conveyor band forming a limiting surface and a second continuous form belt on the limiting surface. The conveyor bands are supported for rotation between conventional tires, the inflation of at least one of the tires controls the pressure on the form belts adjacent their initial point of contact. Resilient metal clips are provided which lock the support and limiting surfaces together during curing of the foam plastic panel.

Abstract: An improvement in the manufacture of flexible densified polyurethane foam wherein the partially cured freely risen foam is fed through a crush conveyor to minimize the density gradient throughout the vertical cross section. The crush conveyor includes an upper crushing section which is arcuate and has a radius of a dimension such that the ratio of the radius of the arc to height of the partially cured freely risen foam is 1.1 to 1 or greater. The crush conveyor has a bottom crushing section which may be arcurate with a radius of a dimension such that the ratio of its radius to the height of the partially cured freely risen foam is also 1.1 to 1 or greater. The radius of the bottom arcuate crushing section may be the same or larger than the radius of the top arc. As an alternative, the bottom crushing section may be planar and may be horizontal, or inclined with respect to the horizontal.

Abstract: A process and apparatus are described for the preparation of continuous polymer foam bunstock having substantially rectangular cross-section. The novel feature comprises a panel member having its downstream end pivotally mounted above a conventional moving trough-shaped mold, the underside of said panel member floating freely in tangential contact with the rising foam in the area immediately following the gel point of said foam but before the point at which the foam is no longer sufficiently mobile to be molded without distortion of the cells thereof.

Abstract: A poppet type check valve for controlled feeding of blowing agent into an assembly for the extrusion of thermoplastic polymeric foam material and, in particular, for controlled feeding of a blowing agent such as pentane into the barrel of an extruder assembly for extrusion of polystyrene foam; and an apparatus assembly comprising such a check valve in combination with the barrel of an extruder for extrusion of such foam materials.

Abstract: An extrusion apparatus and method for producing foamed resin coatings on a wire. A foaming agent and molten resin are poured into a supply portion of an extruding screw and cylinder apparatus. The screw in the supply portion is tapered in the down stream direction. The screw and cylinder apparatus portion adjacent to the supply portion is arranged to blend the resin and foaming agent and has a lower coefficient of extrusion than the supply portion. The metering portion of the screw and cylinder apparatus is adjacent and down stream of the blend portion and has a higher coefficient of extrusion than the blend portion.

Abstract: Disclosed herein is a trough and fall plate particularly adapted for use in producing continuous buns of polyurethane foam which trough and plate are expansible relative to the transverse axis of the plate for forming buns of variable widths. The trough is comprised of a pair of open ended trough sections and detachable end portions, one of the sections being slidably mounted with the other for varying the length of the defined trough and correspondingly the width of the forming bun.

Abstract: An apparatus for in situ preparing and applying foam to a surface, such as a roof, and at the same time applying a membrane onto the surface of the foam, produces a foam-membrane sandwich having an upper surface of controlled smoothness and thickness or pitch, which sandwich is firmly held to the treated surface. The apparatus is normally self-propelled and may be automatically controlled so as to be advanced across the surface to be coated with membrane-covered rigid polymeric foam, preferably of polyurethane foam, as the curing pre-foam and covering membrane are applied. In preferred embodiments of the invention the membrane is a roofing felt or fiberglass web, mat, treated paper or cloth fed from the apparatus from a roll thereon, producing with the roof or other surface to be coated, a form into which a curing pre-foam is deposited as the apparatus is advanced.

Abstract: An apparatus for the manufacture of blocks of expanded cellular material having an essentially circular cross section from foamable means which comprises a stationary generally U-shaped mold having two sides, a bottom and an open top and forming an elongated channel cavity having a circular cross section, conveyor means fitting into said channel cavity and having a downward inclination, means pouring the foamable mass onto the conveyor means at the upper end thereof, means for moving said conveyor means away from said pouring means, means for heating the conveyor means to the same temperature as the mold, a substantial portion of said conveyor means going through said mold, means for fitting the conveyor means within the mold whereby said foamable mass acquires the circular shape of the inner portion of the mold as it moves away from said pouring means and as it solidifies.

Abstract: A continuous mixing method and system for preparation of syrup employed as a starting material for continuously manufacturing plate products therefrom are disclosed. The syrup is prepared by a method in which at least one additive is incorporated into at least one master batch of methyl methacrylate or a monomer mixture of methyl methacrylate and a copolymerizable unsaturated compound or a syrup of a monomer-polymer mixture thereof and the flow of the resulting liquid mixture is continuously combined with the flow from another batch of a syrup of the monomer-polymer mixture in a proportion such that the master batch is less in amount than said other batch, and the combined flows are continuously blended with each other.

Abstract: A method and apparatus for making flat topped foamed buns (e.g. polyurethane) in a continuous foaming process. The method comprises the guiding of a continuous thin film tubular member through gathering devices adjacent the cream line at each side of a conveyor, and subsequently guiding the tubular members upward along guides at an angle and rate determined in accordance with the rate of longitudinal travel and the rate of rise of the foaming reactants so as to encourage the sides of the bun into the same height of rise as the center region of the bun. Continuous slitting of the tubular members at the appropriate elevation allows the material thereof to progress longitudinally with the cured bun.

Abstract: The invention relates to an apparatus for continuous production of a strand of porous thermoplastic material from preferably pre-expanded granules of said material containing an expanding agent. The apparatus comprises an elongated rectangular channel, two opposite sides of which are formed by the horizontal parts facing one another of two superimposed endless belts moving in a closed path between turning rollers. The granules are introduced through the open intake end of said channel and are expanded to final size and sintered together to a porous coherent strand by means of steam fed between the horizontal belt parts facing one another. The steam and the granules are fed into the channel through individual ducts which are separated from one another and connected to the intake end portion of the channel. Usually, a plurality of granule feeding ducts and a plurality of steam supplying ducts are attached to the intake end portion formed as a box of particular shape.

Abstract: Foam blocks are continuously produced on a conveyor belt having lateral boundaries, the application zone for the mixture being adjustable in its inclination, and a feed means for the cover sheet of the conveyor belt being provided before the point at which the mixture is applied.

Abstract: A novel method and apparatus are disclosed for manufacturing a novel adhesive product. The product is a pair of substrates adhered together by compressed hot melt adhesive foam. The foam is created by first mixing a chemical blowing agent, such as powdered azodicarbonamide, into the solid hot melt adhesive at a temperature below the decomposition temperature of the blowing agent. Subsequently, the solid adhesive and powdered blowing agent are heated to a temperature above the melting temperature of the solid adhesive and above the decomposition temperature of the blowing agent while confining the molten mixture under pressure in order to force the gas generated by the decomposition of the blowing agent into solution with the liquid adhesive. The liquid adhesive is subsequently dispensed at atmospheric pressure with the result that the gas is released from the solution and becomes entrapped in the adhesive to form a homogenous closed cellular adhesive foam.

Abstract: A method of removing an article from a chamber having a reduced pressure therein by connecting the chamber to a pool of liquid by a barometric leg is disclosed. The method provides a conveyor in said barometric leg and allows said article to float up into engagement with said conveyor so that the force exerted on the article by the conveyor moves the article down into the pool of liquid and out into the atmosphere.

Abstract: A method and apparatus for making uniform pellets for laser driven fusion reactors which comprises selection of a quantity of glass frit which has been accurately classified as to size within a few micrometers and contains an occluded material, such as urea, which gasifies and expands when heated. The sized particles are introduced into an apparatus which includes a heated vertical tube with temperatures ranging from 800.degree. C to 1300.degree. C. The particles are heated during the drop through the tube to molten condition wherein the occluded material gasifies to form hollow microspheres which stabilize in shape and plunge into a collecting liquid at the bottom of the tube. The apparatus includes the vertical heat resistant tube, heaters for the various zones of the tube and means for introducing the frit and collecting the formed microspheres.

Abstract: An apparatus and method are provided for continuously forming a plastic material, such as a thermoplastic polymer, under pressure against a drum containing irregular surface formations or cavities therein. In one form, injected plastic material is compressed between a bucking member and a substantial area of the surface of a forming drum. The molten casting or molding material is confined to a volume including a portion of the surface of the drum while pressure is applied thereto and until it solidifies. A bucking member such as an endless belt or otherwise shaped member defines a portion of the confined molding volume.

Abstract: An apparatus for producing a foamed thermoplastic resin comprising an extruder including a barrel through which a thermoplastic resin is fed while being melted and a head to extrude said molten resin from said barrel, and gas injector means to inject a gas into said molten resin in said barrel through a gas injecting port in said barrel whereby said foamed thermoplastic resin article is formed by extruding said gas containing molten resin, said gas injector means characterized by comprising a gas metering means or gas flow rate setting means disposed adjacent and connected to said gas injecting port to conduct said gas therethrough while a constant flow rate is maintained, and a volume of a gas passage from said gas flow rate setting means to said gas injecting port in said barrel being sufficiently set for the gas pressure in said gas passage to respond to variation in the pressure of said molten resin in said barrel.

Abstract: Flat plate-type, rod-type or shaped articles of polystyrene foam are continuously produced from preliminarily expanded beads of polystyrene or a mixture of said preliminarily expanded beads with foamed polystyrene pieces recovered for reuse as raw materials by enveloping the beads with a circulating steam-permeable belt, such as cloth belt, passing the enveloped beads through a pressure sealing conduit capable of throttling and succesively a heating zone in a pressure steam chamber at a temperature between 100.degree. and 125.degree.

Abstract: Thermoplastic polymers containing a blowing agent are extruded into an unconfined zone and allowed to partially expand. The polymers are then conveyed through a confined moving passage of predetermined configuration formed, for example, by intermeshing cooled rolls, to shape the extrudate to the predetermined configuration and solidify the surface layers. The extrudate is further cooled by subjecting alternate surfaces to cooled roll surfaces, whereby a continuous ribbon, or shaped extrudate, having a dense skin and a foamed core is formed. The method is particularly applicable to small cross-section profiles which can be cut into short lengths to be useful as ice-cream sticks or tongue depressors.

Abstract: The herein described Apparatus and Method of Producing High-speed Production of a Pressure Generating Product consists of one or more main conveyor units that may be connected together to form a continuous production line, and in which each conveyor unit is formed of upper and lower main parallel conveyors that are provided with endless platen belts, the platens having their opposing ends secured to outer main endless roller bearing link-chains and driven by a suitable source of energy. Intermediate conveyors are secured within the apparatus and located within each of the upper and lower main conveyors and formed of inner parallel endless roller bearing link-chain units effecting independent movable support and pressure means for the platens and independently supported and driven separately from the outer main endless roller bearing link-chains.

Abstract: An apparatus for in situ preparing and applying foam to a surface, such as a roof, and at the same time applying a membrane onto the surface of the foam, produces a foam-membrane sandwich having an upper surface of controlled smoothness and thickness or pitch, which sandwich is firmly held to the treated surface. The apparatus is normally self-propelled and may be automatically controlled so as to be advanced across the surface to be coated with membrane-covered rigid polymeric foam, preferably of polyurethane foam, as the curing pre-foam and covering membrane are applied. In preferred embodiments of the invention the membrane is a roofing felt or fiberglass web, mat, treated paper or cloth fed from the apparatus from a roll thereon, producing with the roof or other surface to be coated, a form into which a curing pre-foam is deposited as the apparatus is advanced.

Abstract: An apparatus for use as an extruder die is disclosed. The die comprises a cylindrical housing surrounded by heating means. Within the die is provided gas injection means which can be used to expand the hot extrudate.