Patents by Inventor Naohiko Obana

Naohiko Obana 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: 11773534
    Abstract: The present invention provides a metal cord having better adhesion to rubber compared to a conventional one, as well as a metal cord-rubber composite and a conveyor belt, including the same. In a metal cord (10) composed of a plurality of metal filaments (11) twisted together, the surfaces of the metal filaments (11) constituting the outermost layer are each provided with a zinc plating layer (16), and the degrees of crystal orientation of the (002) plane and the (102) plane of the surface of the zinc plating layer (16) are less than 120.
    Type: Grant
    Filed: June 12, 2019
    Date of Patent: October 3, 2023
    Assignee: BRIDGESTONE CORPORATION
    Inventors: Naohiko Obana, Yoshiaki Oono
  • Patent number: 11352744
    Abstract: Rubber article-reinforcing steel cord in which corrosion resistance is improved without an increase in weight. In a rubber article-reinforcing steel cord (1), plural sheath strands (3) each formed by twisting together plural steel filaments are twisted together around at least one core strand (2) formed by twisting together plural steel filaments. Core strand (2) and sheath strands (3) are each formed by twisting together one or two core filaments (2c) and (3c) and plural sheath filaments (2s) and (3s), respectively, and a relationship represented by the following Formula (1) is satisfied when a wire diameter of core filament(s) (2c) of core strand (2), a wire diameter of sheath filaments (2s), a wire diameter of core filaments (3c) of sheath strands (3), and a wire diameter of sheath filaments (3s) are defined as dcc, dcs, dsc and dss, respectively: dcc>dcs?dsc>dss (1).
    Type: Grant
    Filed: December 27, 2019
    Date of Patent: June 7, 2022
    Assignee: BRIDGESTONE CORPORATION
    Inventor: Naohiko Obana
  • Patent number: 11220136
    Abstract: Provided is a multi-twisted steel cord for reinforcing a rubber article, the steel cord having cord strength with a small loss as compared to the total strength of filaments constituting the cord and a high rubber penetration. The steel cord includes a plurality of twisted strands in a multi-twisted structure, each strand including a plurality of twisted filaments in two or more layers, in which at least some of the filaments have a tensile strength of 3,000 MPa or more, the steel cord satisfying a filament occupancy of 48% or more and less than 54%, a cord twist angle of 78° or more and less than 84°, an average crossing angle between adjacent filaments other than wrapping filaments of less than 17°, and a gap between adjacent sheath filaments constituting the strand of 0.065 mm or more.
    Type: Grant
    Filed: October 25, 2019
    Date of Patent: January 11, 2022
    Assignee: BRIDGESTONE CORPORATION
    Inventors: Naohiko Obana, Mikito Kondo
  • Publication number: 20210254279
    Abstract: The present invention provides a metal cord having better adhesion to rubber compared to a conventional one, as well as a metal cord-rubber composite and a conveyor belt, including the same. In a metal cord (10) composed of a plurality of metal filaments (11) twisted together, the surfaces of the metal filaments (11) constituting the outermost layer are each provided with a zinc plating layer (16), and the degrees of crystal orientation of the (002) plane and the (102) plane of the surface of the zinc plating layer (16) are less than 120.
    Type: Application
    Filed: June 12, 2019
    Publication date: August 19, 2021
    Applicant: BRIDGESTONE CORPORATION
    Inventors: Naohiko OBANA, Yoshiaki OONO
  • Publication number: 20200131700
    Abstract: Provided are: a rubber article-reinforcing steel cord having excellent corrosion resistance; and a method of producing the same with excellent productivity. In a rubber article-reinforcing steel cord (1), plural sheath strands (3) each formed by twisting together plural steel filaments are twisted together around at least one core strand (2) formed by twisting together plural steel filaments. Brass plating is performed on the steel filaments, and zinc plating is further performed on at least the outer circumference of the brass plating of outermost-layer steel filaments of the sheath strands (3).
    Type: Application
    Filed: December 27, 2019
    Publication date: April 30, 2020
    Applicant: BRIDGESTONE CORPORATION
    Inventors: Naohiko OBANA, Yoshiaki OONO
  • Publication number: 20200131699
    Abstract: Rubber article-reinforcing steel cord in which corrosion resistance is improved without an increase in weight. In a rubber article-reinforcing steel cord (1), plural sheath strands (3) each formed by twisting together plural steel filaments are twisted together around at least one core strand (2) formed by twisting together plural steel filaments. Core strand (2) and sheath strands (3) are each formed by twisting together one or two core filaments (2c) and (3c) and plural sheath filaments (2s) and (3s), respectively, and a relationship represented by the following Formula (1) is satisfied when a wire diameter of core filament(s) (2c) of core strand (2), a wire diameter of sheath filaments (2s), a wire diameter of core filaments (3c) of sheath strands (3), and a wire diameter of sheath filaments (3s) are defined as dcc, dcs, dsc and dss, respectively: dcc>dcs?dsc>dss (1).
    Type: Application
    Filed: December 27, 2019
    Publication date: April 30, 2020
    Applicant: BRIDGESTONE CORPORATION
    Inventor: Naohiko OBANA
  • Publication number: 20200055341
    Abstract: Provided is a multi-twisted steel cord for reinforcing a rubber article, the steel cord having cord strength with a small loss as compared to the total strength of filaments constituting the cord and a high rubber penetration. The steel cord includes a plurality of twisted strands in a multi-twisted structure, each strand including a plurality of twisted filaments in two or more layers, in which at least some of the filaments have a tensile strength of 3,000 MPa or more, the steel cord satisfying a filament occupancy of 48% or more and less than 54%, a cord twist angle of 78° or more and less than 84°, an average crossing angle between adjacent filaments other than wrapping filaments of less than 17°, and a gap between adjacent sheath filaments constituting the strand of 0.065 mm or more.
    Type: Application
    Filed: October 25, 2019
    Publication date: February 20, 2020
    Applicant: BRIDGESTONE CORPORATION
    Inventors: Naohiko OBANA, Mikito KONDO
  • Patent number: 9850354
    Abstract: Provided are a rubber article reinforcing steel wire that is superior in bending fatigue properties to the related art and has a flat cross-sectional shape, and a rubber article using the wire. In a rubber article reinforcing steel wire 10, a major diameter and a minor diameter are substantially perpendicular to each other.
    Type: Grant
    Filed: February 28, 2014
    Date of Patent: December 26, 2017
    Assignee: Bridgestone Corporation
    Inventor: Naohiko Obana
  • Publication number: 20150376351
    Abstract: Provided are a rubber article reinforcing steel wire that is superior in bending fatigue properties to the related art and has a flat cross-sectional shape, and a rubber article using the wire. In a rubber article reinforcing steel wire 10, a major diameter and a minor diameter are substantially perpendicular to each other.
    Type: Application
    Filed: February 28, 2014
    Publication date: December 31, 2015
    Applicant: BRIDGESTONE CORPORATION
    Inventor: Naohiko OBANA
  • Patent number: 7438104
    Abstract: A rubber-covered belt ply forms a belt layer. At least a majority of metal wires in the ply exist as metal wire bundles in which a plurality of metal wires of circular cross-sections and substantially equal wire diameters are aligned in parallel without being twisted together, the metal wire bundles being aligned planarly and in parallel with intervals between the metal wire bundles in a transverse direction. At least one layer, which is a cap layer in which organic fibers are covered with rubber and/or a reinforcing layer which is formed of rubber or whose main component is rubber, is disposed between the belt layer and a tread.
    Type: Grant
    Filed: May 14, 2001
    Date of Patent: October 21, 2008
    Assignee: Bridgestone Corporation
    Inventors: Takao Morii, Sumito Nakagawa, Naohiko Obana
  • Publication number: 20080066844
    Abstract: A steel cord for reinforcing a rubber article and a pneumatic tire. When it is a reinforcement material for a tire belt, the steel cord is capable of satisfying weight lightening, durability and driving stability. The steel cord comprises a core made by parallelly arranging two non-twisted core wires (1) from one layer of sheath made by twisting three to five sheath wires (2) around the core. The outline shape of the cord in a cross-section orthogonal to the axis of the cord is flat The inclination, as seen from the side of the cord, of the core wires is 3° or less relative to the cord axis.
    Type: Application
    Filed: May 23, 2005
    Publication date: March 20, 2008
    Inventor: Naohiko Obana
  • Patent number: 6823706
    Abstract: A steel wire, 0.10-0.40 mm in diameter, obtained by subjecting a high-carbon (0.70-0.90 wt. %) steel wire material to heat treatment and wire drawing, wherein its tensile strength and test values of special repeated torsional tests satisfy a predetermined relation; and a method of manufacturing the same. A high strength steel wire which has so high a ductility as to substantially prevent the wire from being broken even during wire twisting, and which rarely encounters a decrease in the ductility even after the wire has been subjected to age hardening by heating, is obtained, and a method of manufacturing the same is economical.
    Type: Grant
    Filed: March 13, 2000
    Date of Patent: November 30, 2004
    Assignee: Bridgestone Corporation
    Inventors: Yoshikazu Kaneko, Naohiko Obana, Masuhiro Fujita, Hideki Masubuchi, Toshiyuki Kobayashi
  • Patent number: 6530410
    Abstract: As the present invention there is disclosed a pneumatic radial tire comprising a carcass having a smaller tensile rigidity than that of conventional pneumatic radial tires by application of a steel cord having a smaller Young's modulus to the carcass or by application of a smaller amount of a high strength steel cord formed with carcass filaments having a greater tensile strength to the carcass while maintaining the necessary strength of the carcass. In accordance with the present invention, extension of the carcass increases and extension of a belt in the circumferential direction of the tire is suppressed when the tire is inflated by an inner pressure. As a result, compression stress working on the carcass when a vehicle turns decreases and buckling deformation of the steel cord can be prevented. Accordingly, durability is improved.
    Type: Grant
    Filed: December 14, 1999
    Date of Patent: March 11, 2003
    Assignee: Bridgestone Corporation
    Inventor: Naohiko Obana
  • Patent number: 6425428
    Abstract: Steel cord is manufactured by: forming a plurality of bends, per filament length equivalent to one twist pitch, on each of filaments which constitute an outer layer sheath, with the filament length equivalent to one twist pitch being a cycle; twisting these filaments while the bends belonging to the same phase are aligned in a cord axial direction; and subjecting cord side surfaces to compression processing. As a result, flat side surface portions are formed, in which a plurality of filaments forming the outer layer sheath are positioned substantially in the same plane. The steel cord thus formed is used in reinforcement plies for pneumatic radial tires such that the reinforcement plies are laminated in a manner in which the flat side surface portions are mutually parallel.
    Type: Grant
    Filed: March 24, 2000
    Date of Patent: July 30, 2002
    Assignee: Bridgestone Corporation
    Inventors: Shuichi Onuma, Naohiko Obana, Noboru Kusaba
  • Patent number: 6354068
    Abstract: A steel cord comprises a core of three or more filaments bundled without twisting and a sheath of at least one layer comprised of plural filaments wound around the core, wherein all core filaments are arranged in a given rectangle at any section in its longitudinal direction. Such steel cords are used in a belt of a pneumatic tire. And also, these cords are produced by a tubular-type twisting machine having a specified structure.
    Type: Grant
    Filed: June 22, 2000
    Date of Patent: March 12, 2002
    Assignee: Bridgestone Corporation
    Inventors: Shuichi Onuma, Naohiko Obana, Chihiro Yoshida
  • Publication number: 20010054466
    Abstract: A rubber-covered belt ply forms a belt layer. At least a majority of metal wires in the ply exist as metal wire bundles in which a plurality of metal wires of circular cross-sections and substantially equal wire diameters are aligned in parallel without being twisted together, the metal wire bundles being aligned planarly and in parallel with intervals between the metal wire bundles in a transverse direction. At least one layer, which is a cap layer in which organic fibers are covered with rubber and/or a reinforcing layer which is formed of rubber or whose main component is rubber, is disposed between the belt layer and a tread.
    Type: Application
    Filed: May 14, 2001
    Publication date: December 27, 2001
    Applicant: BRIDGESTONE CORPORATION
    Inventors: Takao Morii, Sumito Nakagawa, Naohiko Obana
  • Patent number: 6102095
    Abstract: A corrosion resistant steel cord for reinforcing rubber articles, particularly a belt and/or carcass of a pneumatic tire, has a residual compressive stress inside the twisting helix of each steel filament such that a ratio R.sub.1 /R.sub.0 is less than one, where R.sub.0 is the radius of curvature of a helix in each helically formed steel filament obtained by untwisting of the cord and R.sub.1 is the radius of curvature of the helix after removal of a surface layer from the inside of the helix in the steel filament. The steel filaments have a tensile strength of 4,000-4,800 N/mm.sup.2.
    Type: Grant
    Filed: November 24, 1997
    Date of Patent: August 15, 2000
    Assignees: Bridgestone Corporation, Bridgestone Metalpha Corporation
    Inventors: Naohiko Obana, Yoshikazu Kaneko, Ryuzo Osawa
  • Patent number: 5911675
    Abstract: A steel cord for reinforcing a rubber product includes a core consisting of one steel filament and a sheath consisting of a plurality of steel filaments wound around the core. The steel filament of the core alternately having straight portions, whose axes of the straight portions are disposed on one line, and protrusions formed by bending. The peak of each protrusion is disposed outside of the sheath. The steel cord for reinforcing a rubber product is used in a pneumatic tire. The pneumatic tire includes a carcass having a crown portion and having a toroidal shape, a pair of beads over which the toroidal shape extends, a belt layer or belt layers for reinforcing the crown portion of the carcass, and rubber surrounding the carcass, the pair of bead, and the belt layer(s). The steel cord is used in the carcass and/or the belt layer(s).
    Type: Grant
    Filed: October 23, 1997
    Date of Patent: June 15, 1999
    Assignee: Bridgestone Corporation
    Inventor: Naohiko Obana
  • Patent number: 5873962
    Abstract: A steel cord intended for use to reinforce rubber products is produced by drawing, into a steel filament of 0.10 to 0.40 mm in diameter and more than 3,000 N/mm.sup.2 in strength, a wire rod having a carbon content of more than 0.70% by weight, and twisting a plurality of such steel filaments together. Also a pneumatic tire is provided which employs in at least a portion of a reinforcing member thereof the steel cord improved in corrosion resistance and having an R.sub.1 /R.sub.0 ratio .times.100 which is less than 100, where R.sub.0 is the radius of spiral curvature of the spiraled steel filament resulting from untwisting said steel cord and R.sub.1 is the radius of spiral curvature of said steel filament of which the surface layer inside the spiral is removed by dissolving.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: February 23, 1999
    Assignee: Bridgestone Metalpha Corporation
    Inventors: Yoshikazu Kaneko, Naohiko Obana
  • Patent number: 5822973
    Abstract: A steel cord intended for use to reinforce rubber products is produced by drawing, into a steel filament of 0.10 to 0.40 mm in diameter and more than 3,000 N/mm.sup.2 in strength, a wire rod having a carbon content of more than 0.70% by weight, and twisting a plurality of such steel filaments together. Also a pneumatic tire is provided which employs in at least a portion of a reinforcing member thereof the steel cord improved in corrosion resistance and having an R.sub.1 /R.sub.0 ratio.times.100 which is less than 100, where R.sub.0 is the radius of spiral curvature of the spiraled steel filament resulting from untwisting said steel cord and R.sub.1 is the radius of spiral curvature of said steel filament of which the surface layer inside the spiral is removed by dissolving.
    Type: Grant
    Filed: October 6, 1997
    Date of Patent: October 20, 1998
    Assignee: Bridgestone Metalpha Corporation
    Inventors: Yoshikazu Kaneko, Naohiko Obana