Utilizing Centrifugal Force Patents (Class 264/311)
  • Patent number: 6555037
    Abstract: A method of continuously forming integrally molded structures includes the steps of rotating a plurality of independently movable multisection mold assemblies about a plurality of axes, successively flowing a plurality of polymerizable mixtures over surfaces of each enclosed mold cavity while selectively heating mold sections thereof in a preselected heating profile and monitoring the flowing of each mixture, the heating of the mold sections and the formation of resins therefrom. The monitored mixture flowing, the mold section heating and the formation of each resin are coordinated with each monitored axis rotation. The molded structure is removed after it has achieved structural integrity within the mold cavity, and the steps are repeated to form a multiplicity of the integrally molded structures on a continuing basis. Also, multiaxis molding apparatus for conducting the above method.
    Type: Grant
    Filed: October 19, 2000
    Date of Patent: April 29, 2003
    Inventor: LeRoy Payne
  • Patent number: 6533426
    Abstract: A method for fabricating an optical quality, free-standing, compliant parabolic membrane mirror using an inverted parabolic mandrel created by rotating a liquid confined to a cylindrical polymer and applying a reflective optical stress coating once the substrate has hardened. The stress coating applies a tensile force to the substrate that offsets the stress in the substrate that would otherwise decrease the convexity, and also generates a force to restore the membrane mirror to its original convex parabolic shape when the mirror is deformed by an external force.
    Type: Grant
    Filed: May 2, 2001
    Date of Patent: March 18, 2003
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Richard A. Carreras, Dan K. Marker, James M. Wilkes, Dennis Duneman, James R. Rotge
  • Patent number: 6533988
    Abstract: Rotational moulding process for polymerizing or copolmerizing ethylene for manufacturing ethylene polymers or copolymers having a controlled particle size and morphology. Ethylene is polymerized or copolymerized under ethylene polymerizing conditions in the presence of a supported metallocene catalyst, where the average particle size of the catalyst particles is selected within the range of 14-40 &mgr;m and the residence time at the polymerization is selected so as to achieve a polymer where average particle size is between 0.2-0.5 mm and the proportion of fractions between 0.1-0.6 is at least 80%.
    Type: Grant
    Filed: December 5, 2000
    Date of Patent: March 18, 2003
    Assignee: Borealis Technology Oy
    Inventors: Kalle Kallio, Ulf Palmovist, Hilkka Knuuttila, Anne Marie Fatnes
  • Patent number: 6524514
    Abstract: The invention relates to a method for producing fibrous materials from thermoplastic material, wherein thermoplastic material is molten and fed into a rotating reactor to form a molten film and the fibers are formed on and stretched out along an open edge of the reactor. The fibers are formed on the reactor edge without using nozzles or ducts that are susceptible to clogging so that the rotating reactor is heated in such a way that the molten film has a temperature close to decomposition temperature of the thermic plastic material and the reactor is rotated on the edge at an orbital speed of no less than 10 m/s.
    Type: Grant
    Filed: July 5, 2000
    Date of Patent: February 25, 2003
    Assignee: Microfaser-Repro-GmbH
    Inventors: Gennady G. Volokitin, Vladmir V. Bordinov
  • Publication number: 20030030163
    Abstract: Disclosed is a method for manufacturing composite granules having a homogeneous particle distribution, comprising powders of multimodal particle size distribution and phenol resins, and a method for manufacturing green bodies having homogeneous microstructure without particle separation from the granules.
    Type: Application
    Filed: August 5, 2002
    Publication date: February 13, 2003
    Inventors: Hae-Weon Lee, Huesup Song, Jongho Lee, Joosun Kim, Hyunick Shin
  • Publication number: 20030026925
    Abstract: A method for the production of a double-walled plastic container, comprises the following steps:
    Type: Application
    Filed: July 30, 2002
    Publication date: February 6, 2003
    Applicant: Zweva Rotomoulding
    Inventor: Pieter Van 'T Veer
  • Patent number: 6500367
    Abstract: A method for manufacturing a transfer member suitable for use in an image forming system. A liquid polymer is applied to an internal surface of a rotating drum, spun flat, and cured in place. Additional components of the belt are applied to the rotating mold to form a multi-layered transfer member.
    Type: Grant
    Filed: December 28, 2000
    Date of Patent: December 31, 2002
    Assignee: Xerox Corporation
    Inventors: Carl J. Naus, Robert S. McCallum, Sotos M. Theodoulou, Roman P. Badiali, Paul D. Patcheson
  • Patent number: 6494705
    Abstract: An apparatus for rotational molding provides a mold having first and second mold components defining therebetween a mold cavity. The first mold component includes a mold insert adapted to translate toward the second mold component. A spring-biased latch mechanism restrains the mold insert in the outward disposition, and a touch pad is struck to trigger the latch mechanism and urge the mold insert inwardly while the mold is rotating. With the mold insert latched in the outward disposition, the rotational mold charged with thermoplastic material rotated biaxially and heated. After heating, while the mold assembly continues to rotate, the touch pad is struck to release the latch and cause the mold insert to move inwardly. The mold insert includes structural features that are moved more proximate to opposed mold portions.
    Type: Grant
    Filed: May 18, 2000
    Date of Patent: December 17, 2002
    Assignee: Stephen Feilinger
    Inventor: Craig Wallin
  • Patent number: 6491856
    Abstract: A centrifugally cast hollow fiberglass reinforced plastic (FRP) column having angled corners and straight sides. Interiorly of the column adjacent each corner are angled corner fillers that have straight angled sides adhered to straight interior wall surfaces of the column adjacent the respective corners. During molding, the corner fillers are supported within the mold with their straight sides in parallel spaced relation to the straight interior walls of the mold adjacent the respective mold corners a distance slightly greater than the desired minimum wall thickness of the column, whereby when the mold is rotated, uncured FRP material within the mold will flow by centrifugal force into engagement with the interior walls of the mold and around the corner fillers into the space between the corner fillers and interior walls of the mold adjacent the respective mold corners to form a column having a substantially uniform FRP wall thickness.
    Type: Grant
    Filed: June 26, 2001
    Date of Patent: December 10, 2002
    Assignee: CW Ohio, Inc.
    Inventor: Nicholas N. Noirot
  • Publication number: 20020169033
    Abstract: A method of making an article having a high moment of inertia and the article thus produced which method involves rotating a mold around a central axis, inserting higher density materials into said mold which will be centrifugally forced to the opposite ends of the mold. Then inserting a liquid which is less dense and which will fill the mold and after having infiltrated and attached to the first material that has been placed therein, will harden into solid form.
    Type: Application
    Filed: June 22, 2002
    Publication date: November 14, 2002
    Inventor: Joseph Sery
  • Publication number: 20020145232
    Abstract: A machine for casting radiation cured material with a mold set made of a clear, radiation cured material or other clear material, one or more radiation emitting devices preferably in the ultraviolet and visible range, a rotating mechanism to move the mold set from a horizontal or vertical load/unload position to vertical fill and cure position at the radiation devices, and one or more injection mechanisms attached to the mold set to fill the mold set and then seal at the part wall preventing cure of material in the line and resulting in a minimal gate mark. Alternatively the molds can be filled and then rotated before and during cure to create a hollow part.
    Type: Application
    Filed: April 5, 2001
    Publication date: October 10, 2002
    Inventors: Gregory C. Zettel, Donald L. Sudduth
  • Patent number: 6435069
    Abstract: A cover for a rotary die is centrifugally cast with multiple layers to substantially eliminate stress when the cover is cast in an arcuate shape for use in a die cutting system. A locking mechanism attached to ends of the cover is designed to be convenient to install on and remove from a cutting cylinder.
    Type: Grant
    Filed: November 23, 1999
    Date of Patent: August 20, 2002
    Assignee: IAM Corporation
    Inventors: Alan D. Kirkpatrick, Jr., Christopher D. Kirkpatrick
  • Publication number: 20020109272
    Abstract: Molding techniques and apparatus wherein at least one adjustable edge component can be used to alter the dimensions of the mold cavity between molding operations. Also disclosed are techniques for incorporating reinforcing composite elements into molded plastic parts. Most preferably, a rotomolding technique is used to fabricate a substantially homogenous composite panel for use as a partition or bulkhead.
    Type: Application
    Filed: October 19, 2001
    Publication date: August 15, 2002
    Inventors: Chad Nelson, Roger Nelson, Matt Nelson
  • Patent number: 6432343
    Abstract: In a process of making a rotationally symmetrical article, such as rope pulleys, running wheels or the like, from plastic material such as cast polyamides, raw material melts of plastic material and predetermined amounts of catalysts, activators and stabilizers are prepared at different formulation and composition to impart the melts with different mechanical strengths after polymerization. The raw material melts are poured into a heated, rotating mold in succession in dependence on a polymerization pattern of the raw material melts. After complete polymerization of the melts, the mold is opened, and the finished article can be removed from the mold for optional refinishing procedure.
    Type: Grant
    Filed: February 10, 2000
    Date of Patent: August 13, 2002
    Assignees: Mannesmann AG, Ensinger GmbH & Co.
    Inventors: RĂ¼diger Zollondz, Walter Wagner
  • Publication number: 20020105111
    Abstract: An apparatus and method of manufacturing seal rings. The apparatus and method ensures that there is no wasted material during the manufacturing process and further ensures that the seal ring is manufactured to exacting standards without the need for any further milling processes. The apparatus and method has a mold which is heated and rotated at a predetermined rotation rate. A molten material is poured into the mold during the rotation thereof. The mold is then cooled and the rotation is decelerated so that the solidified material can be removed therefrom.
    Type: Application
    Filed: February 5, 2001
    Publication date: August 8, 2002
    Inventors: John V. Grabel, Kevin D. Hayes
  • Publication number: 20020102369
    Abstract: Disclosed is a cellulose ester film comprising a polymer prepared by polymerizing at least one ethylenically unsaturated monomer selected from vinyl esters, vinyl esters having a functional group, acrylic esters, and acrylic esters having a functional group, wherein the polymer has a weight average molecular weight of not more than 5,000.
    Type: Application
    Filed: July 10, 2001
    Publication date: August 1, 2002
    Applicant: Konica Corporation.
    Inventors: Kunio Shimizu, Toru Kobayashi
  • Publication number: 20020084877
    Abstract: A bi-chromal ball production apparatus and method where the bi-chromal ball material is fed from opposite sides of the disk, reconfiguring the internal geometry of the apparatus, and precisely configuring the bi-chromal ball material feeding slit. The bi-chromal ball production apparatus has a disk that rotates, a first supply structure that supplies a first bi-chromal ball material to the disk from a first direction, a second supply structure tube that supplies a second bi-chromal ball material to the disk from a second direction and a motor that rotates the disk. The bi-chromal ball production apparatus includes a first reservoir and a first slit defined by the disk and a top body, a second reservoir and a second slit defined by the disk and a bottom body. An inner surface of each of the first and second reservoir is parabola shaped.
    Type: Application
    Filed: December 28, 2000
    Publication date: July 4, 2002
    Inventors: Dennis Martell, Nicolas K. Sheridan, Joseph M. Crowley, Matthew E. Howard, Michelle Ann Remus
  • Patent number: 6409954
    Abstract: A one-piece face mask with an integral inflatable cushion for use in providing an anesthetic to a patient. The mask has a dome shape outer wall terminating at its circumference in a thickened base on which the inflatable cushion is supported. The one-piece mask is formed by a combination of a rotational plastic molding process and gravity casting, which enables the different parts of the mask to be made of different thicknesses related to the function performed by the different parts in use of the mask.
    Type: Grant
    Filed: October 5, 1999
    Date of Patent: June 25, 2002
    Assignee: Roto Plastics, Inc.
    Inventor: David C. Mulligan
  • Patent number: 6410141
    Abstract: Spherical particles having a diameter between 0.007″ and 0.040″ are formed from melt extruded thermo-plastic material suitable for casting on a heated mold surface and melting thereon to form a thin layer of material having a nominal thickness of 0.040″ that is cooled and removed from the mold surface as a part having a porosity less than a visually observable threshold. The process includes the steps of providing microspheres formed of blended and melt extruded thermo-plastic, plasticizers and pigment additives that constitute less than 5% by weight of the blend and shaped as a smooth round spherical particle; providing a heated casting surface and distributing a predetermined charge of such microspheres against the heated casting surface; melting the microspheres as a layer of thermoplastic material having a porosity less than 0.003 inches and thereafter cooling and removing the non-porous layer from the casting surface.
    Type: Grant
    Filed: September 16, 1999
    Date of Patent: June 25, 2002
    Assignee: Davidson Textron Inc.
    Inventor: Robert A. Grimmer
  • Patent number: 6405565
    Abstract: An apparatus and process for fabricating tubing used in the making of chalcogenide fibers. The apparatus features a three-sectioned melt/spin ampoule that allows for fabricating the chalcogenide tubing without introducing impurities and contaminants, in a self-contained apparatus.
    Type: Grant
    Filed: November 1, 2000
    Date of Patent: June 18, 2002
    Assignee: Corning Incorporated
    Inventors: Bruce G. Aitken, David H. Crooker, Mark L. Powley
  • Patent number: 6398995
    Abstract: A high impact resistant rotationally molded door and process for molding the door has the hinge post integrally attached to the rotationally molded skin of the door. A hinge member is provided that has a perforate U-shaped metal sheet bonded to preferably the upper portion of the hinge post. The sides of the U-shaped metal sheet are spaced sufficiently apart so that registration with the subsequently rotationally molded plastic skin of the door occurs. This hinge member at the perforate metal sheet rapidly heats during rotational molding. The perforate metal thus bonds to integrally mold with the skin of the door. This bonding occurs as the hinge post is molded within the hollow door construction along its hinging edge. The hinge member attaches at the perforate U-shaped metal sheet to the skin of the door while all other portions of the hinge post are free to move with respect to the door. The door is thus formed without door warping during curing and shrinking of rotationally molded plastic door body.
    Type: Grant
    Filed: October 10, 2000
    Date of Patent: June 4, 2002
    Assignee: Chase Industries Inc.
    Inventors: Daniel Richard Eisenlord, Thomas Lee McCormick
  • Patent number: 6370916
    Abstract: It is an object of the present invention to reduce variations in dimensional accuracy such as the outer-diameter accuracy and roundness of a flare shape and the concentricity between the bulb portion and the flare portion. According to the present invention, a lower mold (1) formed of a metallic material and forming a recess flare shape (1a) that is subjected to surface treatment forms a flare shape (21b) almost identical to the flare shape (1a) by means of the rotational motion of a rotating head portion (2). An upper mold (10) is fitted in the lower mold (1) to form a flare-shaped gap portion (13), into which glass is forced to form a flare shape (22).
    Type: Grant
    Filed: January 21, 2000
    Date of Patent: April 16, 2002
    Assignee: Matsushita Electronics Corporation
    Inventor: Tatsuhiro Yabuki
  • Patent number: 6336025
    Abstract: A method of producing an endless intermediate transfer belt having at least one position detecting hole for detecting a rotational position of the endless intermediate transfer belt in an image forming apparatus, including rotating a cylindrical mold having at least one protruding member on an inner peripheral surface thereof, supplying a liquid material onto the inner peripheral surface of the cylindrical mold wherein the liquid material is formed into the endless intermediate transfer belt and the at least one position detecting hole is formed in the endless intermediate transfer belt by the at least one protruding member, heating the endless intermediate transfer belt so as to harden the endless intermediate transfer belt, and taking out the endless intermediate transfer belt from the cylindrical mold.
    Type: Grant
    Filed: September 28, 2000
    Date of Patent: January 1, 2002
    Assignee: Ricoh Company, Ltd.
    Inventor: Kazuchika Saeki
  • Patent number: 6322348
    Abstract: A molding apparatus is disclosed which includes a first support having spaced apart vertical posts, and a first set of mold halves positioned between the vertical posts. A second support is provided having positioned thereon a second set of mold halves. A clamp bar is positioned on the vertical posts adjacent the second support so as to extend across the mold halves of the second set of mold halves. A grip member secured to the first support is movable between an engage and disengage position, wherein in the engage position a clamp engages the grip member and the clamp bar so as to drive the respective sets of mold halves into sealing contact with each other, so as to form two mold cavities. In the disengage position, the grip member is clear of the clamp so as to permit the clamp to also act as a device to separate the supports when the molding process is over. Methods of using this equipment in an automated rotational molding process are also disclosed.
    Type: Grant
    Filed: October 18, 1999
    Date of Patent: November 27, 2001
    Assignee: Norstar Aluminum Molds, Inc.
    Inventor: Gary R. Guzikowski
  • Publication number: 20010041233
    Abstract: The present invention pertains to a process for the rotational molding of polyurethane composite articles. The process is carried out by placing a polyurethane composite precursor composed of a hardener, a resin and a filler, wherein the hardener comprises one or more organic di- or polyisocyanates, and the resin comprises of one or more compounds containing at least two isocyanate-reactive groups, the filler is about 15% to about 50% by weight, or alternatively, about 15% to about 35% by weight, or, in a preferred embodiment, about 25% by weight, the % weight being based upon total weight of the mixture, and either the hardener or the filler optionally contains additives and/or catalysts in a rotational mold, and rotating said mold until at least the first cure time of the molded article is completed. The invention a also pertains to the articles produced by use of this method.
    Type: Application
    Filed: March 23, 1999
    Publication date: November 15, 2001
    Inventor: TIMOTHY RUSCHE
  • Patent number: 6312633
    Abstract: A method of producing dashboards, door or side trim panels for motor vehicles with a predetermined breaking line for an airbag flap is described. To accomplish this, slush material is introduced into a mold which can be heated to a molding temperature and determines the shape of the slush membrane, where the slush material is distributed and deposited on the heated mold surface by rotating the mold and is then sintered and gelled. After cooling the mold, the slush membrane is removed from the mold by unmolding. To create a predetermined breaking line, a mold having a divider on its mold surface at the location of the predetermined breaking line to be created is used. By controlled rotation and/or positioning of the mold while applying the powder and/or gelling the slush material, a reduction in the layer thickness of the slush material to an extent that establishes a predetermined breaking line is achieved.
    Type: Grant
    Filed: July 22, 1998
    Date of Patent: November 6, 2001
    Assignee: Benecke Kaliko AG
    Inventors: Gerd Henning Kiesel, Walter André
  • Patent number: 6258453
    Abstract: A composite with a thermoplastic matrix and fiber reinforcement is made by rotation of an exit die about a roving of continuous fiber in the presence of a thermoplastic melt. The rotation causes opposing inner and outer helical flow conditions which reduce the melt viscosity of the polymer by shear thinning while dragging and directing the polymer into the fiber roving thereby wetting and dispersing the fiber. A composite structure is formed with a polymer rich skin and a core region of unidirectionally aligned polymer and fiber. The polymeric skin is composed of helically aligned polymer chains which are coiled by the rotation around the core to compress the core region and enhance fiber wet out.
    Type: Grant
    Filed: September 18, 1997
    Date of Patent: July 10, 2001
    Inventor: Lawrence V. Montsinger
  • Patent number: 6193924
    Abstract: A method of making a container assembly comprises the step of molding a container body over a portion of a plastic fixture. A plastic fixture is disposed in the mold. The mold has an inner surface defining an outer surface of a container. The fixture includes an opening and a portion having at least one ridge on a surface which is to be embedded in the body of the container. The fluid plastic material is disposed in the mold. The plastic material is then molded over the mold inner surface and the fixture surface thereby forming the container body. The plastic material contacts the ridge and melts or softens the ridge. The ridge is then deformed forming a locking engagement between the container body and the fixture. As the plastic material cools and hardens, the plastic container body partially engulfs the fixture to provide a secure seal between the fixture and container body.
    Type: Grant
    Filed: October 9, 1998
    Date of Patent: February 27, 2001
    Assignee: Moeller Marine Products
    Inventor: O. C. Huse
  • Patent number: 6180203
    Abstract: A method for rotational molding of articles, including the step of rotationally molding a mixture of particulate plastics material comprising at least one thermoplastics material having a first particle size and a second thermoplastics material having a larger particle size wherein, in use, said first thermoplastic material fuses to form an outer skin and subsequently said second thermoplastics material fuses to form an inner skin bonded to the outer skin of a resultant molded article. The method may also include the step of incorporating a quantity of rollable molded reinforcing elements in the mold with said first and second thermoplastics materials, wherein the reinforcing elements are located in a spaced array thereby forming bridges between opposed inner skin surfaces as they expand. Articles, such as a shipping pallet, rotationally molded using the method are also disclosed.
    Type: Grant
    Filed: October 14, 1998
    Date of Patent: January 30, 2001
    Inventor: Peter J. Unkles
  • Patent number: 6113782
    Abstract: Tubular bundles are potted in a housing, such as in an oxygenator or a pheresis unit. Spacer material is placed into the housing to cover the first ends of the tubular elements. A layer of potting material is placed into the housing covering the spacer material, and then solidified in place to seal between each of the tubular elements and the housing. The spacer material is then removed from the housing to expose the first ends of the tubular elements. In the oxygenator, at least some of the tubes are gas exchange tubes having an interior lumen and a tube wall which is permeable for oxygen and carbon dioxide flow through the tube wall. The potting separates the housing into manifold chambers communicating with the interior of the tubes and a blood flow chamber sealed from the manifold chambers. Blood flows over the exterior surface of the tubes. Other tubes may be heat transfer tubes, such as for carrying a heat transfer fluid to control the temperature of the blood.
    Type: Grant
    Filed: July 28, 1998
    Date of Patent: September 5, 2000
    Assignee: Terumo Cardiovascular Systems Corporation
    Inventor: Ronald J. Leonard
  • Patent number: 6071459
    Abstract: A metathesis polymerized polyolefin article is provided which includes a flame-retarding agent. The method of making the article includes polymerizing an olefin monomer via a metathesis polymerization reaction in the presence of a one-part metathesis polymerization catalyst and a compatible flame-retarding agent.
    Type: Grant
    Filed: September 4, 1998
    Date of Patent: June 6, 2000
    Assignee: A. O. Smith Corporation
    Inventors: Mark Warner, Michael A. Giardello
  • Patent number: 6060006
    Abstract: A baluster or spindle is formed by a casting method, and has a rigid, dense, hollow outer shell forming a decoratively shaped body portion having closed, planar opposed ends. A conduit extends completely through the baluster, providing attachment means to a railing system. The hollow interior of the baluster is injected with a high density polyurethane foam to increase its weight, density, and resistance to breakage. The method of forming a baluster or spindle includes the combined method steps of placement of a mesh sheet adjacent each end of the mold, and then subsequent agitation of the mold. Agitation includes simultaneous spinning and rocking of the mold about its longitudinal axis. The mesh sheet retains the casting material against the end surfaces of the mold, and is completely encapsulated by the casting material such that the mesh sheet is not visible on the surface of the finished product.
    Type: Grant
    Filed: February 11, 1999
    Date of Patent: May 9, 2000
    Inventor: Peter Savenok
  • Patent number: 6036897
    Abstract: A rotational molding apparatus that utilizes stationary temperature sensors, e.g., infra-red thermometry (IRT) sensors, for continuously monitoring the temperature of the molds during rotation.
    Type: Grant
    Filed: March 17, 1998
    Date of Patent: March 14, 2000
    Assignee: Remcon Plastics, Inc.
    Inventor: Paul J. Nugent
  • Patent number: 6012212
    Abstract: An apparatus requiring storage of a liquid that needs agitation includes a plastic tank that is rotationally molded around an agitation portion. In a preferred embodiment, an asphalt sealcoat application system has such a plastic rotary molded tank mounted on a powered vehicle or trailer and utilizes a pump connected to a hose and spray wand for application of sealcoat on an asphalt surface. The tank is preferably formed of low density polyethylene resin and the agitation portion includes a plurality of paddles and a shaft extending from the interior of the tank for mixing the sealcoat liquid. The polyethylene tank is rotary molded around the assembled agitation portion. The invention includes the methodology of molding the tank, a tank molded by said methodology, and the apparatus for accomplishing said methodology.
    Type: Grant
    Filed: April 29, 1998
    Date of Patent: January 11, 2000
    Inventor: Craig M. Erickson
  • Patent number: 6001440
    Abstract: The present invention relates to a heat-conductive polyimide film comprising a heat-conductive powder dispersed therein with a concentration gradient. The film can be produced, for example, by centrifugal casting. The film can be used as an excellent component or member in those fields in which heat conductivity is required in addition to mechanical characteristics, heat resistance and chemical resistance. For example, it is used as a thermal fixation member in a laser printer.
    Type: Grant
    Filed: October 22, 1997
    Date of Patent: December 14, 1999
    Assignee: Gunze Limited
    Inventors: Tsuneo Miyamoto, Takashi Kuraoka, Junya Kanetake, Naoki Nishiura, Nobuaki Kobayashi, Tetsuo Sadamitsu
  • Patent number: 5998030
    Abstract: Spherical particles having a diameter between 0.007" and 0.040" are formed from melt extruded thermoplastic material formed of blended and melt extruded thermoplastic and pigment.
    Type: Grant
    Filed: July 25, 1997
    Date of Patent: December 7, 1999
    Assignee: Davidson Textron Inc.
    Inventor: Robert A. Grimmer
  • Patent number: 5985504
    Abstract: The invention is directed to a cost effective method for manufacturing an electrophotographic-photosensitive-body comprising forming a photosensitive layer on the internal surface of a cylindrical mold, polymerizing a resin for a transparent substrate using a centrifugal casting method, and integrating the resin obtained with the photosensitive layer. The electrophotographic-photosensitive-body obtained may be used for an internally illuminating electrophotographic apparatus and that has an excellent printing performance.
    Type: Grant
    Filed: June 9, 1998
    Date of Patent: November 16, 1999
    Assignee: Fuji electric Co., Ltd.
    Inventor: Noriaki Kawata
  • Patent number: 5976445
    Abstract: A method for producing zirconia fused cast refractories, which comprises casting zirconia fused cast refractories containing at least 33 wt % of a ZrO.sub.2 component utilizing a mold, wherein the mold is rotated on a rotation axis, so that at least a portion of a meltage of raw material poured into the mold, is cooled to solidify under a centrifugal force of at least 1.2 G.
    Type: Grant
    Filed: March 18, 1998
    Date of Patent: November 2, 1999
    Assignee: Asahi Glass Company Ltd.
    Inventors: Ryunosuke Kuroda, Kazuyori Takatsuji
  • Patent number: 5945384
    Abstract: In order to produce tubular moldings of high-temperature superconducting material based on oxides of bismuth, calcium, strontium, copper and optionally lead, a homogeneous melt of the oxide mixture in a predefined stoichiometry having temperatures from 900 to 1300.degree. C. is made to flow into a casting zone. The casting zone, as a function of its internal diameter, rotates at from 200 to 1500 rpm about its axis which is inclined by at least 15.degree. with respect to the horizontal. The solidified molding is taken from the casting zone and annealed for from 4 to 150 hours at from 700 to 900.degree. C. in an oxygen-containing atmosphere.
    Type: Grant
    Filed: June 25, 1996
    Date of Patent: August 31, 1999
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Eberhard Preisler, Joachim Bock
  • Patent number: 5932163
    Abstract: A PVC film cover including a down and interned marginal portion terminating in a thickened bead, the marginal portion tapering in thickness from the bead toward the central body portion of the cover. The cover is produced through the use of a shape-conforming mold into whose central portion liquid PVC is dispensed while the mold is rotating. The liquid PVC moves over the mold surfaces outward toward the outer marginal portion thereof by centrifugal force and rotation of the mold is terminated and the mold is quickly inverted into a downwardly opening position whereupon the excess liquid PVC at the outer periphery of the mold flows slowly down to a reversely turned edge for forming the bead of the cover. In quick succession, the mold is heated in order to gel and then harden the liquid PVC, mold is cooled and the cover is thereafter removed from the mold.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: August 3, 1999
    Inventor: Louis S. Ashley
  • Patent number: 5888440
    Abstract: A method of making an impeller having inner and outer portions of polyurethane resin having different flexibilities with the outer portion bonded to the inner portion and having greater flexibility than the inner portion, includes rotating a centrifugal casting mold containing a polyurethane resin forming material of predetermined composition, introducing into the inner portion of the mold another polyurethane resin forming composition of different composition than the first material, centrifugal casting the inner and outer portions together, and curing the resulting shape to form a disk having bonded inner and outer portions of polyurethane resin having different flexibilities.
    Type: Grant
    Filed: February 26, 1993
    Date of Patent: March 30, 1999
    Assignee: Norstone, Inc.
    Inventor: Michael Steinmetz
  • Patent number: 5879598
    Abstract: A centrifuge (18) is used to introduce a fluid, particularly a viscous fluid such as an encapsulating resin, into a cavity in a container (10), particularly a small cavity such as the inside of an electronic component housing. Measured quantities of the fluid are placed in dispensing vessels (28) in the centrifuge opposite the containers to be filled. The dispensing vessels have openings (36) through which the fluid can flow when centrifugal force is applied. On the application of this force, all the fluid flows out of the vessels into the containers.
    Type: Grant
    Filed: August 12, 1996
    Date of Patent: March 9, 1999
    Assignee: Electronic Techniques (Anglia) Limited
    Inventor: Kevin McGrane
  • Patent number: 5874016
    Abstract: A concrete column forming tube and method of making same for receiving poured concrete column therein to produce a concrete column is characterized by a smooth inside coated surface in the forming tube to eliminate spiral seam lines and other undesirable characteristics on the outside surface of the formed concrete column. The tube is formed from spirally-wound plies of paper adhered together and has a centrifugally-cast epoxy resin coating sprayed onto the inside surface of the spirally-wound tube while the tube is rotating to produce a smooth inside coated surface on the forming tube.
    Type: Grant
    Filed: October 4, 1993
    Date of Patent: February 23, 1999
    Assignee: Sonoco Products Company
    Inventors: Robert D. Bacon, Jr., Arnold B. Floyd, Jr., Troy W. Johnson, Jr., James R. Martin, Honor S. Bonds, John F. Whitehead, Wim van de Camp
  • Patent number: 5868979
    Abstract: A method for controlling an automatic rotamolding process, the method including the steps of: metering a first prescribed quantity of plastics material powder into a hopper to be delivered to a rotatable mold as a first shot; heating the mold; when the mold reaches a prescribed temperature, delivering the first shot of powder from the hopper to the mold and simultaneously rotating the mold so as to distribute the powder over an interior surface of the mold; heating the mold in accordance with a predetermined temperature-time characteristic; cooling the mold; and ejecting the finished rotamolded product from the mold.
    Type: Grant
    Filed: October 15, 1996
    Date of Patent: February 9, 1999
    Assignee: Automated Plastic Systems Pty. Ltd.
    Inventor: Robert John Glenn
  • Patent number: 5868976
    Abstract: A process for forming a dialysis membrane utilizing a mixture of ion exchange resin components and thermoplastic resin components mixed together in a dry state and rotationally formed into a membrane. The rotational forming process includes rotational molding using temperature to conform the components to the shape of the mold as well as rotational casting using solvents and phase inversion to form the membrane. The resulting membrane is a smooth, dimensionally stable, efficient dialysis membrane.
    Type: Grant
    Filed: March 14, 1997
    Date of Patent: February 9, 1999
    Assignee: Koch Membrane Systems, Inc.
    Inventors: John P. Puglia, Ronald P. Brochu
  • Patent number: 5866085
    Abstract: A syringe encapsulation device having a melt chamber heated by forced hot air to sufficient temperature to melt the plastic bodies of the syringes, where the melt chamber is coaxially mounted onto a rotating shaft and rotated when the plastic is in the molten state such that the molten plastic is centrifugally driven to the outer periphery of the melt chamber to safely encapsulate the needles once the molten plastic has hardened.
    Type: Grant
    Filed: May 19, 1997
    Date of Patent: February 2, 1999
    Assignee: Imagination Medical, Inc.
    Inventor: Richard Yelvington
  • Patent number: 5858294
    Abstract: A method and apparatus for fabricating columns, wherein the apparatus includes a column fabricating assembly and a column extractor. The column fabricating assembly includes a unitary column mold and a mold support assembly. The unitary column mold is reusable and is fabricated specially for the task of fabricating a column therein. Uncured column materials are placed into the unitary column mold and the unitary column mold is enclosed in the mold support assembly. The uncured column materials cure, and thus the column is formed, while the unitary column mold is encased in and spun by the mold support assembly. The unitary column mold is removed from the mold support assembly with the column therein. The column extractor is used to extract the column from the unitary column mold; the unitary column mold is secured by the column extractor and the column extractor pulls the column out of the unitary column mold.
    Type: Grant
    Filed: August 5, 1997
    Date of Patent: January 12, 1999
    Assignee: Focal Point Products, Inc.
    Inventors: Jorge Del Valle, Fred L. Hicks, Steven W. Spires, Daniel J. Brown
  • Patent number: 5849341
    Abstract: A powder slush molding apparatus comprises a reservoir (4) containing a powder material (8) used as material for the powder slush molding apparatus and having a sealing member (21) on an end portion of a powder material introduction opening (6), and a metal mold (1) which is maintained at a high temperature and is coupled to the reservoir (4) for forming a skin molding by melting the powder material (8) poured from the reservoir (4) while rotating the reservoir (4). In the powder slush molding apparatus, the sealing member (21) comprises a seal tube (23) tubular in section which is fixed along the end portion of the powder material introduction opening (6) and a stringlike seal inner member (24) which is inserted in the seal tube (23).
    Type: Grant
    Filed: June 12, 1997
    Date of Patent: December 15, 1998
    Assignee: Kansei Corporation
    Inventors: Masahiro Johno, Yuzo Ushikubo
  • Patent number: 5840461
    Abstract: A method of producing a substrate for a photoreceptor having an exposing device therein for use in an electrophotographic apparatus, including the steps of: injecting polymerizable liquid material into a die whose inner surface is cylindrical; polymerizing the polymerizable liquid material while rotating and heating the die so that a substrate is formed inside the die; and removing the substrate from the die after the polymerizing, wherein the polymerizable liquid material is a transparent resin material and a thickness of the substrate is controlled according to an injecting amount of the polymerizable liquid material.
    Type: Grant
    Filed: March 28, 1997
    Date of Patent: November 24, 1998
    Assignee: Konica Corporation
    Inventors: Satoshi Haneda, Hisayoshi Nagase, Hiroyuki Tokimatsu, Masahiro Onodera, Shuta Hamada, Toshihide Miura, Fumitaka Mochizuki
  • Patent number: RE36340
    Abstract: A centrifugally cast plastic pipe comprised of a polymer derived from monomers polymerized in bulk is provided. A pressurized cylindrical mold provides smooth inner and outer surfaces. Pipes with a wall thickness of from 1/8 inch to 3 inches and an outer diameter of 1 inch to 12 feet are provided.
    Type: Grant
    Filed: July 16, 1997
    Date of Patent: October 12, 1999
    Assignee: A. O. Smith Corporation
    Inventors: Charles S. Woodson, Michael J. Darnall, Norman A. Deumite