Induction Heating Patents (Class 264/457)
  • Patent number: 4878827
    Abstract: For automotive interior trim molding assemblies having a vinyl skin shell, a reinforcement insert, and an intermediate reaction type polyurethane foam composition, a vinyl skin shell which has a gasket-type peripheral edge formed thereon for abutting cooperation with the reinforcement insert to prevent leakage of the foam therepast during the foam reaction period in a reaction mold. The gasket-type peripheral edge is formed on the otherwise thin shell by a tear edge, against which plastisol builds up in a substantially triangular cross section during the shell molding period in a heated slush mold.
    Type: Grant
    Filed: August 22, 1988
    Date of Patent: November 7, 1989
    Assignee: Davidson Textron Inc.
    Inventor: John Muller
  • Patent number: 4855096
    Abstract: A method for producing articles of polyurethane or the like wherein a mold of the article shape is positioned to centrifugally receive a polyurethane composition comprising polyisocyanates, polyol, water and fluorocarbons such that the polyurethane molecules striking the wall of the mold are broken to provide a resulting smooth non-porous outer skin for the article and wherein additional polyurethane materials provide a foamed interior for the article. The water serves as a reactive polyol and reacts with the polyisocyanate to create carbon dioxide gas which yields increased expansion pressure which causes the foaming polymer to produce a uniform skin around a cellular inner core.
    Type: Grant
    Filed: May 23, 1986
    Date of Patent: August 8, 1989
    Inventor: Vincent F. Panaroni
  • Patent number: 4836963
    Abstract: An improved rotational molding method for making a laminated plastic structure of the type in which successive charges of particulate plastics are released in a mold cavity rotating in an oven to coalesce successively along the mold cavity wall after which the mold is removed from the oven for cooling. By removing the rotating mold from the oven prior to completion of the formation of the inside layer, cooling of the outside of the mold will be concurrent with coalescence of the inside layer. This shortens the time of the molding cycle and reduces warping problems.
    Type: Grant
    Filed: May 26, 1987
    Date of Patent: June 6, 1989
    Assignee: Old Town Canoe Company
    Inventor: Llewellyn A. Gilman, Jr.
  • Patent number: 4675139
    Abstract: Gaskets are formed in container closures fabricated from polyolefin resins exhibiting substantially no response to heat activation by radio frequency electrical energy by introducing a vinyl chloride plastisol containing a vinyl chloride polymer resin and a plasticizer having a loss factor in the range of 0.1-12 into the closure. The closure is preheated to 55.degree. to 100.degree. C. by conventional means and then the plastisol is fused in the closure by exposure to a field of radio frequency electrical energy.
    Type: Grant
    Filed: October 21, 1985
    Date of Patent: June 23, 1987
    Assignee: Continental Can Company, Inc.
    Inventors: Alfred W. Kehe, Thomas T. Fetters
  • Patent number: 4671753
    Abstract: Rotational molding apparatus includes a chemical supplying portion, a chemical mixing portion, a mold portion, a mold supporting portion, a mixture delivery portion and a control portion. The chemical mixing portion includes a tubular member disposed in a substantially horizontal orientation with a plurality of spaced angled deflector sections. The mold portion includes a pair of spacially connected substantially parallel frame sections. The mold supporting portion includes spaced upstanding sections with rotating clamping members selectively engageable with opposite edges of the mold portion. The mixture delivery portion includes a translatable elongated hollow probe member that is selectively connected with the tubular member.
    Type: Grant
    Filed: August 19, 1985
    Date of Patent: June 9, 1987
    Inventor: LeRoy Payne
  • Patent number: 4657716
    Abstract: A shoe sole of elastomeric material is formed with at least one pressurized gas cell at least one wall of which is defined by a layer in which a substantially inextensible reinforcement is embedded to prevent bulging. The cell envelope can be formed by rotational casting of a liquid material within a cavity of a wear layer to simultaneously penetrate the reinforcing layer.
    Type: Grant
    Filed: November 30, 1984
    Date of Patent: April 14, 1987
    Assignee: Lim Kunststoff Technologie Gesellschaft
    Inventor: Oskar J. Schmidt
  • Patent number: 4637907
    Abstract: A tool for use in a latex dip process for producing a latex skin in a given configuration, the tool being formed by producing an electro-formed female mold from a sculpture of the desired configuration, casting a vinyl skin from the electro-formed female mold, removing the vinyl skin to expose a hollow interior, and stuffing the vinyl skin with a composition of materials, having the characteristics of providing rigidity to the vinyl skin and approximately zero buoyancy in a latex bath.
    Type: Grant
    Filed: April 5, 1985
    Date of Patent: January 20, 1987
    Assignee: Mattel, Inc.
    Inventors: James D. Hegel, Davin W. Johnson
  • Patent number: 4591469
    Abstract: An improved method for manufacturing a foam-filled polyurethane foam bun from foam particles having uniformly dispersed therewith large amounts of solid material bonded together with new polyurethane foam is described. The method comprises uniformly applying a liquid flexible polyurethane foam-forming material to a dispersion of foam particles and solid material to provide a blend, distributing the blend within a mold, and foaming and curing the foam-forming material by a plurality of steaming steps wherein the mold is flipped from a first to second position between steaming steps. The foam buns have a uniform density gradient. Foam buns are disclosed having a variation in density across the foam bun. There is also disclosed an improved char-forming foam obtained as a result of using boric acid in the foam-forming formulation.
    Type: Grant
    Filed: January 30, 1985
    Date of Patent: May 27, 1986
    Assignee: Wm. T. Burnett & Co., Inc.
    Inventors: Michael S. Buchanan, Gregory B. Davis
  • Patent number: 4533696
    Abstract: The invention relates to polymer powder compositions consisting of 1-99 wt. % of a polymer powder component A and 99-1 wt. % of a polymer powder component B, the average particle size of component A being smaller than that of component B, and to the preparation of hollow objects by rotational molding using these polymer powder compositions.
    Type: Grant
    Filed: February 18, 1983
    Date of Patent: August 6, 1985
    Assignee: Stamicarbon B.V.
    Inventors: Jan Schrijver, Arnold Vossebeld
  • Patent number: 4519964
    Abstract: A process for preparing plastic articles having an outer rigid shell and an inner polystyrene foamed core, whereby pre-expanded polystyrene beads are foamed and fused inside a hollow thermoplastic shell, comprising, coating the inside of the shell prior to introducing the polystrene beads into the hollow shell, with a thermoplastic bonding layer.
    Type: Grant
    Filed: January 19, 1984
    Date of Patent: May 28, 1985
    Assignee: Rotoplas, Ltd.
    Inventor: Haim Rosen
  • Patent number: 4485057
    Abstract: Insulated pipeline components are produced by positioning a steel pipe in the cavity of a casting mold with the pipe ends protruding therefrom. The dimensions of the cavity are greater than those of the inner pipe, and in the space between the inner pipe and the contact surfaces of the mold cavity a plastic powder is introduced, the powder being melted by heating of the mold. The mold is then rotated in a manner well known in rotational molding technique so that centrifugal force drives the molten plastic material against the contact surfaces of the mold cavity to form a plastic jacket; and after the mold has cooled the component is removed and expandable plastic material is supplied to the space between the inner pipe and the plastic jacket and is foamed. The resulting component has an exactly centered inner pipe, lacks conventional joints and can be produced at relatively low cost in a manner complying with industrial safety requirements.
    Type: Grant
    Filed: February 16, 1983
    Date of Patent: November 27, 1984
    Assignee: Lindab Nord AB
    Inventors: Olle Kristensson, Bo R. G. Nystrom
  • Patent number: 4477400
    Abstract: A polyolefin composition having improved adhesion to foamable plastic substrates, comprising an intimate mixture of about 20% to about 99.5% by weight of a first stabilized polyolefin powder and from about 0.5% to about 80% by weight of a second at most slightly stabilized polyolefin powder, said second powder having a crystalline melting point which is at least 1.degree. higher than that of said first powder and wherein said second powder has the ability to be oxidized under process conditions.
    Type: Grant
    Filed: February 6, 1984
    Date of Patent: October 16, 1984
    Assignee: Stamicarbon B.V.
    Inventor: Erik R. Peerlkamp
  • Patent number: 4476076
    Abstract: A method of forming a synthetic article by open forming techniques by providing a fluid composition containing a predominant quantity of synthetic resin and having a capability for delayed, substantial gas evolution. To produce reinforced articles, the composition is applied to the reinforcement at a temperature below a predetermined gas evolution temperature and is subjected to fluid spreading conditions to thoroughly wet the elements of reinforcement. Subsequently, the fluid composition reaches the predetermined temperature, the resultant gas evolution effectively expands the composition while it remains in thorough wetting contact with the reinforcement elements, and the resin then solidifies and cures to produce an intimately reinforced, expanded article. In important embodiments the preponderant gas evolution results from the reaction of an organic hydroperoxide with an isocyanate in the presence of a surfactant.
    Type: Grant
    Filed: August 10, 1981
    Date of Patent: October 9, 1984
    Assignee: Whitney & Company, Inc.
    Inventor: Glen W. Saidla
  • Patent number: 4470785
    Abstract: The invention relates to apparatus for moulding a tire for a wheel rim by means of a mould having mould parts, said mould parts being movable between a closed working position in which they enclose a mould cavity with the shape of the tire and an open position in which said mould parts are spaced apart, wherein in the open position of the mould parts a hollow tire core is positioned in the mould cavity while being receivable with respect to said parts, wherein the mould parts are moved into the working position, in which a residual cavity not occupied by the tire core is left free in the mould cavity, said mould defining the residual cavity being adapted to receive synthetic resin foam for moulding a tire body. Preferably the tire core is arranged on the wheel rim before being positioned with respect to the mould parts.
    Type: Grant
    Filed: January 27, 1983
    Date of Patent: September 11, 1984
    Inventor: Arie Koorevaar
  • Patent number: 4464263
    Abstract: A pleated paper filter element (10) has a fluid-permeable foamed-plastic shield (16) formed on one of its faces to firmly and accurately position the adjacent folds of filter media. The shield (16) is formed in situ and bonds to the filter media without the use of an intermediate adhesive so as to form a unitary structure. A method of making such a filter involves disposing a foamable liquid plastic (34) near a pleated paper filter unit and foaming the plastic. Prior to solidification, the plastic is effective to bond directly to the filter media. A mold (22) for making such a filter element includes a receptacle (28) for receiving a quantity of liquid plastic and a filter unit and for holding them in the proper relation while the plastic is foamed. The mold receptacle includes projections (30) which form perforations (18) in the solidified plastic and which provide for fluid flow communication through the filter element.
    Type: Grant
    Filed: February 18, 1982
    Date of Patent: August 7, 1984
    Assignee: Fram Corporation
    Inventor: Peter Brownell
  • Patent number: 4457729
    Abstract: A rotational molding process for manufacturing objects having a foamed plastic substrate adhered to an outer polyolefin coating layer, and having improved adhesion therebetween comprising the combination of steps of: preparing a first outer coating layer of a stabilized polyolefin; forming a second inner layer of an at most slightly stabilized polyolefin contiguous with and on the interior surface of said first outer layer; and thereafter introducing a foamable plastic material onto the interior surface of said second layer and foaming said plastic material thereagainst thereby the foamed plastic is bonded to said second interior surface.
    Type: Grant
    Filed: August 31, 1981
    Date of Patent: July 3, 1984
    Assignee: Stamicarbon B.V.
    Inventor: Erik R. Peerlkamp
  • Patent number: 4440899
    Abstract: A polyolefin composition having improved adhesion to foamable plastic substrates, comprising an intimate mixture of about 20% to about 99.5% by weight of a first stabilized polyolefin powder and from about 0.5% to about 80% by weight of a second at most slightly stabilized polyolefin powder, said second powder having a crystalline melting point which is at least 1.degree. higher than that of said first powder and wherein said second powder has the ability to be oxidized under process conditions.
    Type: Grant
    Filed: August 31, 1981
    Date of Patent: April 3, 1984
    Assignee: Stamicarbon B.V.
    Inventor: Erik R. Peerlkamp
  • Patent number: 4438056
    Abstract: A smooth, plastic-lined corrugated pipe having an intermediate layer of plastic foam. The pipe is made by internally coating a corrugated pipe with a foaming mixture and pressing an expandable cylinder of plastic sheet liner against the foaming mixture until the foam solidifies. An expandable mandrel apparatus presses the plastic sheet liner into position.
    Type: Grant
    Filed: July 6, 1982
    Date of Patent: March 20, 1984
    Assignee: Bethlehem Steel Corporation
    Inventor: Bernard J. Bast
  • Patent number: 4379104
    Abstract: The invention relates to a method of moulding a tire for a wheel rim by means of a mould having mould parts, said mould parts being movable between a closed working position in which they enclose a mould cavity with the shape of the tire and an open position in which said mould parts are spaced apart, wherein in the open position of the mould parts a hollow tire core is positioned in the mould cavity while being receivable with respect to said parts, wherein the mould parts are moved into the working position, in which a residual cavity not occupied by the tire core is left free in the mould cavity, said residual cavity. Preferably the tire core is arranged on the wheel rim before being positioned with respect to the mould parts. The invention also provides a device for moulding a tire and a tire obtained with the aid of the method and device.
    Type: Grant
    Filed: March 16, 1981
    Date of Patent: April 5, 1983
    Inventor: Arie Koorevaar
  • Patent number: 4285903
    Abstract: A molding system and method are provided together with articles produced thereby wherein rapidly setting molding material is introduced into a mold and made to conform to the walls of the mold cavity by movement of the mold prior to the setting of the molding material. Precise automatic control is effected, not only of one or more resinous molding materials but also of catalyst's employed to rapidly set the molding material and also of a plurality of power operated devices which serve to move the mold about a plurality of axes. Automatic control is also effected of power operated means for varying the operation of one or more mixing chambers, valves and the like in a preprogrammed molding cycle. In a particular form, feedback control is employed to assure the predetermined operation of the motors and power operated devices controlling the complete molding operation.
    Type: Grant
    Filed: January 3, 1980
    Date of Patent: August 25, 1981
    Inventor: Jerome H. Lemelson
  • Patent number: 4158686
    Abstract: Method for making a solar collector or converter, the converter comprising a series of at least three spaced wall members defining a plurality of flow passageways for the same or different heat exchange fluids, each passageway being in communication with a storage device for converted energy, preferably a multi-compartmented storage device having a separate compartment for each heat exchange fluid.
    Type: Grant
    Filed: June 25, 1976
    Date of Patent: June 19, 1979
    Inventor: Alfred Boeckmann
  • Patent number: 4152183
    Abstract: The disclosure relates to a method for producing hollow cylindrical structures, and more particularly for producing hollow cylindrical structures which may serve as collector electrodes for electrostatic precipitators; the method comprising the forming of a first resin and fiberous structural layer on a rotating mandrel, then applying a foam structure forming resin on the first structural layer, then permitting the foam structure to cure into a structural condition, then lathe turning the periphery of the foam structure to a uniform annular cylindrical surface, then applying a second layer of resin and fiberous material to form an external structural layer and then finishing the exterior of the last mentioned structural layer to a uniform annular shaped surface, and finally coating the last mentioned surface with a water resistent resinous material and then removing the glossy surface from said last mentioned material to prevent surface tension of water from separating flow on said last mentioned surface; the
    Type: Grant
    Filed: July 15, 1977
    Date of Patent: May 1, 1979
    Assignee: Dart Industries, Inc.
    Inventors: Horst Honacker, James H. Sharpe
  • Patent number: 4123307
    Abstract: An apparatus and method are provided for forming large filament reinforced composite bodies. In one form a substrate is formed by rotational molding a plastic material in a mold cavity after which the molding is removed from the cavity and placed in a filament winding fixture wherein filamentary material is wound thereon to provide substantial reinforcement for the article and strengthen the outer stratum thereof. In a particular form, the rotational molding contains a rigid tubular member extending therethrough and secure therein during the rotational molding process and is utilized for the purpose of supporting the rotational molding in the filament winding fixture. In another form, an inflatable substrate is constructed with a rod or tubular member extending therethrough which member is utilized to support the inflated member in a filament winding fixture.
    Type: Grant
    Filed: October 12, 1976
    Date of Patent: October 31, 1978
    Inventor: Jerome H. Lemelson
  • Patent number: 4042663
    Abstract: A metal seat pan is placed inside a rotational casting mold to define part of a rotational casting cavity into which is introduced rotationally castable material for forming a flexible plastic seat cover. A rotational casting operation produces a closed, hollow seat cushion shell defined by the seat pan and the flexible plastic cover. Foaming ingredients are introduced into the hollow shell to form a resilient foamed plastic interior. The resulting seat cushion is monolithic, without seams or joints and has no removable parts or mechanically joined components which will come apart from each other.
    Type: Grant
    Filed: December 16, 1974
    Date of Patent: August 16, 1977
    Assignee: Coach and Car Equipment Corporation
    Inventor: Arthur J. Harder, Jr.
  • Patent number: 4033023
    Abstract: A procedure for refurbishing hollow metal buoys that have been surveyed out of service. The buoy repair method involves removing a metal section, filling the buoy interior with polyurethane foam, welding back the removed metal section and coating the metal exterior with fiber glass-resin composition. Buoys repaired in this manner are essentially maintenance free.
    Type: Grant
    Filed: October 8, 1975
    Date of Patent: July 5, 1977
    Inventors: Albert E. Slaughter, Nan Burke Slaughter
  • Patent number: 3996322
    Abstract: The invention contemplates a machine and method whereby rotation of an annular mold is used to develop a homogenous longitudinal and radial distribution of foaming plastic. The foaming plastic is introduced into the mold cavity during mold rotation and, particularly where mold-cavity length substantially exceeds mold-cavity diameter, a longitudinal traverse is imparted to the introduction of foaming material during rotation of the mold. The cavity is closed to permit foamed filling of the mold, and a polymerizing cure is effected prior to mold opening and product removal. The particular machine herein described is notable (a) for its ready mechanical release from both inner and outer molding contact with the product, (b) for its inherent adaptability to production of a selected one of a plurality of inner and outer profiles and sizes in the product, and (c) for its safe accommodation of fast-foaming and curing plastics, even for relatively large product diameter or girth.
    Type: Grant
    Filed: July 3, 1973
    Date of Patent: December 7, 1976
    Assignee: Armstrong Cork Company
    Inventors: Charles D. Snelling, Theodore E. Andrews, John J. Weller
  • Patent number: 3984511
    Abstract: The method of forming, by rotational molding, a foamed polystyrene article that has a continuous covering of thermoplastic material such as low density polyethylene. The method requires the utilization of polystyrene beads that contain substantially less than the maximum possible percentage of blowing or expanding agent. A high temperature, low residence time heating step is found to be adequate for the formation of the article.
    Type: Grant
    Filed: February 25, 1974
    Date of Patent: October 5, 1976
    Assignee: Dart Industries Inc.
    Inventor: Sidney G. Lammers
  • Patent number: 3976821
    Abstract: A hollow multilayered article is rotationally molded by introducing into the mold particles of a hompolymer or copolymer of ethylene containing a crosslinking agent and heating the mold during rotation thereof to melt this first polymeric layer. Solid particles of a different polymer are then introduced into the mold at a time after at least substantially all of the particles of the first polymer have melted and prior to the time when the inner surface of the first layer would become smooth and glossy. The mold is then rotated and heated to melt the second polymer. The mold is then cooled and the multilayered article removed.
    Type: Grant
    Filed: May 14, 1973
    Date of Patent: August 24, 1976
    Assignee: Phillips Petroleum Company
    Inventors: Guy E. Carrow, Robert L. Rees
  • Patent number: 3962390
    Abstract: A method of producing shaped articles of thermoplastic resin having a non-foam layer and foam layer, which comprises introducing into a mold thermoplastic resin particles not containing a heat-decomposable blowing agent and thermoplastic resin particles containing such a blowing agent and having a greater heat capacity than said resin particles not containing a blowing agent, heating the mold and, in the meantime, moving said particles in said mold to effect the heat-melting of said particles as well as the heat-decomposition of said blowing agent.
    Type: Grant
    Filed: May 21, 1974
    Date of Patent: June 8, 1976
    Assignee: Sekisui Kagaku Kogyo Kabushiki Kaisha
    Inventors: Hisayuki Mori, Eiichi Adachi, Yoji Noguchi
  • Patent number: 3936565
    Abstract: A rigid plastic article includes an outer skin surface of a polyolefin plastic material such as cross-linked high density polyethylene tightly secured to a foam core the latter preferably of a high density or medium density polyethylene. Such a laminated plastic article has substantial rigidity and strength, particularly flexural strength, the latter being greater for the laminate than the sum of the individual flexural strengths of the skin and foam separately. Due to the thermal and sound insulation, rigidity, flotation, impact resistance, relative lightweight and weatherability characteristics, the laminate offers particular advantages for use in complex shapes such as automotive doors and tops, camper tops, boats and recreational vehicles and containers such as water tanks, carboys and the like. Such products may be manufactured by a rotational molding procedure in which each of the plastic materials is sequentially introduced into a rotating heated mold.
    Type: Grant
    Filed: May 3, 1974
    Date of Patent: February 3, 1976
    Assignee: Hollowform, Inc.
    Inventor: Elmer H. Good