Patents by Inventor Robert A. Barr

Robert A. Barr has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11285652
    Abstract: A no solid bed extruder screw for processing a material to a molten state has a body with a helical thread formed thereon, the thread having pushing and trailing surfaces. The body has an outer surface and extends longitudinally between feed and discharge ends. A channel for receiving the material to be processed is defined between the outer surface of the body and an outer diameter of the thread bounded by the pushing surface and the trailing surface of the thread. A volume of the channel decreases in a plurality of revolutions of the thread in a direction from the feed end to the discharge end. A channel depth between the pushing surface and the trailing surface decreases for a first portion of the channel toward the feed end and increases for a second portion of the channel toward the discharge end.
    Type: Grant
    Filed: February 17, 2020
    Date of Patent: March 29, 2022
    Inventor: Robert A. Barr
  • Publication number: 20210252764
    Abstract: A no solid bed extruder screw for processing a material to a molten state has a body with a helical thread formed thereon, the thread having pushing and trailing surfaces. The body has an outer surface and extends longitudinally between feed and discharge ends. A channel for receiving the material to be processed is defined between the outer surface of the body and an outer diameter of the thread bounded by the pushing surface and the trailing surface of the thread. A volume of the channel decreases in a plurality of revolutions of the thread in a direction from the feed end to the discharge end. A channel depth between the pushing surface and the trailing surface decreases for a first portion of the channel toward the feed end and increases for a second portion of the channel toward the discharge end.
    Type: Application
    Filed: February 17, 2020
    Publication date: August 19, 2021
    Inventor: Robert A. Barr
  • Publication number: 20190082769
    Abstract: A helmet for wearing by a sports player comprises: a bubble-shaped body having a hollow interior surrounded by a wall and an opening formed in the wall for inserting a head of the player, and a fastening device for releasably fastening the body to shoulder pads being worn by the player. At least a portion of the wall is formed of a transparent material. Alternate designs are also disclosed, including a helmet constructed of a plastic-coated wireframe, and a non-transparent plastic helmet with a face mask, where in all cases the helmet is rigidly but releasably attached to a chest pad or shoulder pad worn by the player, so that impact forces on the helmet are not transferred to the player's head.
    Type: Application
    Filed: September 18, 2018
    Publication date: March 21, 2019
    Inventor: Robert A. Barr
  • Publication number: 20180079126
    Abstract: A plastic melt machine includes a feed screw rotatably mounted in a barrel and driven in rotation about a longitudinal screw axis of the feed screw by a screw drive to plasticize material, and an apparatus for driving a device independently of the feed screw. The device can be any rotatable device associated with the feed screw wherein the device is rotatable about a drive axis and is in fluid communication with the barrel to receive the plasticized material. The drive axis is coaxial with the screw axis. A drive shaft couples the device to the device drive, or to the screw drive through a speed changer, for rotating the device independently of the rotation of the feed screw by the screw drive.
    Type: Application
    Filed: September 22, 2016
    Publication date: March 22, 2018
    Inventors: Robert A. Barr, Jeffrey A. Myers
  • Publication number: 20150273753
    Abstract: An extruder screw comprises a core extending longitudinally from a feed end to a discharge end thereof. The core has a helical primary thread formed thereon. At least one discontinuity is fog lied in the primary thread to divide the primary thread into a plurality of primary thread portions spaced apart from each other in a longitudinal direction of the core. The at least one discontinuity formed in the primary thread may be formed adjacent a downstream end of a compression section of the screw or spanning a transition from the compression section to a section of the screw disposed downstream of the compression section. The discontinuity in the primary thread militates against the problem of solids wedging by allowing any solid materials being processed by the extruder screw to expand and break apart prior to the core reaching a maximum outer diameter.
    Type: Application
    Filed: January 21, 2015
    Publication date: October 1, 2015
    Inventors: Robert A. Barr, Jeffrey A. Myers
  • Publication number: 20140020157
    Abstract: Various helmets for protecting a wearer's head are provided that include a shell, at least one pad, and a lower portion coupled to the shell. The shell is configured to receive the wearer's head and can be formed from an elastomeric material. The pad is coupled to an interior of the shell and configured to be positioned between the wearer's head and the shell, where the pad can include one or more fluid filled bladders. The lower portion is configured to limit flexion, extension, and lateral bending of the wearer's head.
    Type: Application
    Filed: July 19, 2013
    Publication date: January 23, 2014
    Inventor: Robert A. Barr
  • Patent number: 6599004
    Abstract: An extruder screw includes an energy transfer section divided into successive barrier sections in which a channel formed by a first thread is divided into at least two sub-channels by a second thread. A ratio of the difference in outer diameters of the threads is approximately inversely proportional to the ratio of the lengths of adjacent ones of the barrier sections.
    Type: Grant
    Filed: May 3, 2001
    Date of Patent: July 29, 2003
    Inventor: Robert A. Barr
  • Publication number: 20020163853
    Abstract: An extruder screw includes an energy transfer section divided into successive barrier sections in which a channel formed by a first thread is divided into at least two sub-channels by a second thread. A ratio of the difference in outer diameters of the threads is approximately inversely proportional to the ratio of the lengths of adjacent ones of the barrier sections.
    Type: Application
    Filed: May 3, 2001
    Publication date: November 7, 2002
    Inventor: Robert A. Barr
  • Patent number: 6454454
    Abstract: An extruder screw mechanism has a barrel that is heated by heating coils, an internal screw, and a cylindrical melt sleeve having a plurality of circumferentially spaced, axially extending, radial slots there through located between the external barrel and the internal screw. Another embodiment of the extruder has a barrel and an internal screw, with the internal screw having either a single central axial bore or a plurality of internal axial bores. The internal screw is provided with a plurality of external threads, with the threads each having a curved starting portion with a helix angle that has a finite value and gradually increases along an initial portion of the screw until the threads are substantially linear and parallel to the axis of the screw along the melting portion of the screw; a related embodiment has threadless portion separating the linear threads from the curved upstream threads.
    Type: Grant
    Filed: July 11, 2000
    Date of Patent: September 24, 2002
    Inventor: Robert A. Barr
  • Patent number: 6254266
    Abstract: An extruder-mixer has a plurality of rotor rings provided on the downstream end of a motor driven extruder shaft mounted for rotation in a conventional heated barrel or stator. The rings comprise a plurality of spaced driven rotor rings spaced apart from each other and a plurality of non-driven but rotatable floating rings interleaved between each pair of driven rotor rings. Both rings have parallel upstream and downstream faces between which polymer flow passageways extend so that the polymer melt moves downstream first through one type of ring followed by movement through the other type of ring and the viscosity of the melt causes the rotatable floating rings to be rotated by the driven rings at a slower speed than the driven rings so that shearing force on the melt effects mixing of the melt.
    Type: Grant
    Filed: November 12, 1998
    Date of Patent: July 3, 2001
    Inventors: Robert A. Barr, Jeffrey A. Myers
  • Patent number: 5988866
    Abstract: A mixer for plasticable resins has a fixedly positioned heated barrel with a power driven screw mounted axially in the barrel bore, a driven rotor is axially aligned with and extending in a downstream direction from the downstream end of power driven screw. A series of elongated rotor flow transfer cavities are in the outer surface of the rotor. The rotor flow transfer cavities extending inwardly and are arranged in a plurality of axially aligned rows and a plurality of annular rows concentric to the axis of the rotor. A floating sleeve is coaxially positioned over the power driven rotor and interposed between the rotor and the barrel so as to be capable of independent rotation relative to both the power driven rotor and the barrel.
    Type: Grant
    Filed: May 22, 1998
    Date of Patent: November 23, 1999
    Inventor: Robert A. Barr
  • Patent number: 4779989
    Abstract: A mixer assembly for mixing fluid material in the bore of a barrel wherein the mixer assembly includes structure for mixing and pumping toward its outlet end the material fed thereto comprising a stator assembly fixed in the barrel having outer cylindrical surface portions conforming substantially to the surface of the bore and having a stator bore provided with a groove-interrupted inner surface, and a driven rotor member having a groove-interrupted outer surface confronting the inner stator surface.
    Type: Grant
    Filed: December 1, 1986
    Date of Patent: October 25, 1988
    Inventor: Robert A. Barr
  • Patent number: 4558954
    Abstract: A screw extruder and positive displacement wave pump assembly for plasticating or melting solid plastic material or the like, including an extruder screw member in an elongated cylindrical barrel having an upstream end and a downstream or discharge end, the screw being rotatably housed in portions of the barrel adjacent the upstream end. The screw has a helical thread of plural turns integral with the core of the screw having a minimum clearance to the barrel for feeding the plastic material along the screw from its feed end to its discharge end.
    Type: Grant
    Filed: December 12, 1984
    Date of Patent: December 17, 1985
    Inventor: Robert A. Barr
  • Patent number: 4558991
    Abstract: A positive displacement wave pump assembly for pumping liquid or gaseous or plastic fluids or mixtures thereof with solids or the like, including an elongated cylindrical tube or barrel having an upstream end and a downstream or discharge end, a drive shaft rotatable in portions of the barrel adjacent the upstream end, and a positive displacement wave pump is located in the barrel near the outlet end having a stator frame and a rotor member rotatable therein coupled to and driven by the driveshaft. The rotor member has an outer surface of developed helical coutour providing a plural turn helical thread of wide rounded form to position a stack of slidable sealing discs guided for diametric sliding movement by the rotor passing therethrough to form a seris of pumping pockets which progress longitudinally through the pump.
    Type: Grant
    Filed: January 10, 1985
    Date of Patent: December 17, 1985
    Inventor: Robert A. Barr
  • Patent number: 4519712
    Abstract: A screw extruder and positive displacement pump assembly for plasticating or melting solid plastic material or the like, including an extruder screw member in an elongated cylindrical barrel having an upstream end and a downstream or discharge end, the screw being rotatably housed in portions of the barrel adjacent the upstream end. The screw has a helical thread of plural turns integral with the core of the screw having a minimum clearance to the barrel for feeding the plastic material along the screw from its feed end to its discharge end. A positive displacement Moineau type pump is located in the barrel near the outlet end having a stator member and a rotor member rotatable therein coupled to and driven by the screw, the stator and rotor members having confronting surfaces of developed helical contours providing helical threads of wide rounded form with a lesser number of threads on the rotor providing a series of pumping pockets which progress longitudinally through the pump section.
    Type: Grant
    Filed: September 6, 1984
    Date of Patent: May 28, 1985
    Inventor: Robert A. Barr
  • Patent number: 4405239
    Abstract: Extruders are widely used to transform solid plastic materials into molten plastic materials. Because of the low thermal conductivity of plastic materials and the inefficient mixing of the plastic materials inside an extruder, the heat is not evenly distributed in the material being processed and some portion of the material emerges from the extruder with excessive heat. This invention discloses a new screw with a novel mixing section which promotes mixing of the hot, molten material with the cold, unmolten material inside the screw channel by its unique geometry, thereby improving the heat transfer from the hot, molten material to the cold, unmolten material and increasing the energy efficiency of the extruder.
    Type: Grant
    Filed: April 13, 1982
    Date of Patent: September 20, 1983
    Inventors: Chan I. Chung, Robert A. Barr