Patents by Inventor Hiroaki Sakamoto

Hiroaki Sakamoto 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: 7282103
    Abstract: The present invention provides an iron-base amorphous alloy thin strip excellent in soft magnetic properties, an iron core manufactured by using said thin strip, and a mother alloy for producing a rapidly cooled and solidified thin strip. More specifically, the present invention is an iron-base amorphous alloy thin strip produced by rapidly cooling and solidifying molten metal by ejecting it onto a moving cooling substrate through a pouring nozzle having a slot-shaped opening, characterized by having an ultra-thin oxide layer of a thickness in the range from 5 to 20 nm on one or both of the surfaces of the amorphous mother phase containing P in the range from 0.2 to 12 atomic %.
    Type: Grant
    Filed: March 31, 2003
    Date of Patent: October 16, 2007
    Assignee: Nippon Steel Corporation
    Inventors: Hiroaki Sakamoto, Yuichi Sato
  • Publication number: 20060292027
    Abstract: A high-purity ferroboron contains 0.02 mass % or more of P and 0.03 mass % or less of Al, with the balance Fe, B and unavoidable impurities. The high-purity ferroboron may further contain 0.03 mass % or less of Ti.
    Type: Application
    Filed: August 30, 2006
    Publication date: December 28, 2006
    Applicant: Nippon Steel Corporation
    Inventors: Sunao Takeuchi, Yuichi Sato, Hiroaki Sakamoto
  • Publication number: 20060166029
    Abstract: The present invention provides an Fe—Cr—Al based stainless steel sheet and double layered sheet having a high Al content of greater than 6.5%, honeycomb bodies employing the stainless steel sheet or double layered sheet, and a process for fabrication of the steel sheet or double layered sheet. The sheet is a high Al-containing Fe—Cr—Al based stainless steel sheet or high Al-containing double layered sheet characterized by comprising, by weight, Cr: 10-30% and Al: >6.5%-15%. Preferably, the steel sheet further comprises either or both Ti: 0.02-0.1% and Nb: 0.02-0.3%, and also comprises La: 0.01-0.1%, Ce: 0.01-0.1% and P: 0.01-0.05%. It also preferably comprises Cu: 0.01-1.0% by weight, and preferably further comprises Mg: 0.001-0.1% by weight. There is also provided a honeycomb body fabricated using the Fe—Cr—Al based stainless steel sheet.
    Type: Application
    Filed: November 20, 2003
    Publication date: July 27, 2006
    Inventors: Tooru Inaguma, Shogo Konya, Hiroaki Sakamoto, Motonori Tamura
  • Publication number: 20050120281
    Abstract: An electronic control unit includes a main microcomputer and a sub-microcomputer. Both the microcomputers include buffers for initialization and buffers for normal processing. At the time of startup of the main microcomputer and the sub-microcomputer, the sub-microcomputer reads out a correction value from a memory, stores the correction value in its buffers for initialization, and also transmits the correction value to the main microcomputer, which stores the correction value in its buffers for initialization.
    Type: Application
    Filed: November 9, 2004
    Publication date: June 2, 2005
    Applicant: FUJITSU TEN LIMITED
    Inventors: Tsuyoshi Takatori, Shinji Yamashita, Hiroaki Sakamoto
  • Patent number: 6830636
    Abstract: A process of producing a high toughness iron-based amorphous alloy strip, using a single roll liquid quenching method, the strip having a thickness of more than 55 &mgr;m up to 100 &mgr;m and a width of 20 mm or more and having a fracture strain &egr;f satisfying the relationship &egr;f>0.1 where &egr;f=t/(D−t), t=thickness of the strip, and D=bent diameter upon fracture, &egr;f being determined by bending the strip with a free cooling surface thereof facing outward, the process comprising the steps of: ejecting a molten metal alloy through a nozzle; applying the ejected molten metal alloy to a surface of a rotating roll; allowing the applied molten metal alloy to be quenched by the roll surface to form an amorphous strip of the metal alloy, the strip being quenched at a cooling rate, determined at a free surface thereof, of 103° C./sec or more in a temperature range of from 500° C. to 200° C.
    Type: Grant
    Filed: November 1, 2002
    Date of Patent: December 14, 2004
    Assignee: Nippon Steel Corporation
    Inventors: Hiroaki Sakamoto, Toshio Yamada, Takashi Sato
  • Publication number: 20040140016
    Abstract: The present invention provides an iron-base amorphous alloy thin strip excellent in soft magnetic properties, an iron core manufactured by using said thin strip, and a mother alloy for producing a rapidly cooled and solidified thin strip. More specifically, the present invention is an iron-base amorphous alloy thin strip produced by rapidly cooling and solidifying molten metal by ejecting it onto a moving cooling substrate through a pouring nozzle having a slot-shaped opening, characterized by having an ultra-thin oxide layer of a thickness in the range from 5 to 20 nm on one or both of the surfaces of the amorphous mother phase containing P in the range from 0.2 to 12 atomic %.
    Type: Application
    Filed: December 4, 2003
    Publication date: July 22, 2004
    Inventors: Hiroaki Sakamoto, Yuichi Sato
  • Publication number: 20030183041
    Abstract: The present invention provides methods for: producing high-purity ferroboron by using inexpensive mass-produced steel as a base iron; and producing a mother alloy for an iron-base amorphous alloy and an iron-base amorphous alloy, the alloys having excellent properties, by using the ferroboron thus produced as a raw material. The methods include: a method for producing high-purity ferroboron by using mass-produced steel obtained through a converter, an electric furnace or the like and having an Al content of 0.03 mass % or less as a base iron; a method for producing a mother alloy by adjusting the chemical composition thereof by adding a diluent base iron and auxiliary materials to the produced ferroboron; and a method for producing an iron-base amorphous alloy by preferably using mass-produced steel obtained through a converter or an electric furnace and having an Al content of 0.
    Type: Application
    Filed: March 27, 2003
    Publication date: October 2, 2003
    Inventors: Sunao Takeuchi, Yuichi Sato, Hiroaki Sakamoto
  • Publication number: 20030047249
    Abstract: A process of producing a high toughness iron-based amorphous alloy strip, using a single roll liquid quenching method, the strip having a thickness of more than 55 &mgr;m up to 100 &mgr;m and a width of 20 mm or more and having a fracture strain &egr;f satisfying the relationship &egr;f>0.1 where &egr;f=t/(D−t), t=thickness of the strip, and D=bent diameter upon fracture, &egr;f being determined by bending the strip with a free cooling surface thereof facing outward, the process comprising the steps of: ejecting a molten metal alloy through a nozzle; applying the ejected molten metal alloy to a surface of a rotating roll; allowing the applied molten metal alloy to be quenched by the roll surface to form an amorphous strip of the metal alloy, the strip being quenched at a cooling rate, determined at a free surface thereof, of 103° C./sec or more in a temperature range of from 500° C. to 200° C.
    Type: Application
    Filed: November 1, 2002
    Publication date: March 13, 2003
    Applicant: Nippon Steel Corporation
    Inventors: Hiroaki Sakamoto, Toshio Yamada, Takashi Sato
  • Patent number: 6506268
    Abstract: A process of producing a high toughness iron-based amorphous alloy strip, using a single roll liquid quenching method, the strip having a thickness of more than 55 &mgr;m up to 100 &mgr;m and a width of 20 mm or more and having a fracture strain &egr;f satisfying the relationship &egr;f>0.1 where &egr;f=t/(D-t), t=thickness of the strip, and D=bent diameter upon fracture, &egr;f being determined by bending the strip with a free cooling surface thereof facing outward, the process comprising the steps of: ejecting a molten metal alloy through a nozzle; applying the ejected molten metal alloy to a surface of a rotating roll; allowing the applied molten metal alloy to be quenched by the roll surface to form an amorphous strip of the metal alloy, the strip being quenched at a cooling rate, determined at a free surface thereof, of 103° C./sec or more in a temperature range of from 500° C. to 200° C.; and continuously coiling the quenched strip at a temperature of 200° C.
    Type: Grant
    Filed: October 30, 1996
    Date of Patent: January 14, 2003
    Assignee: Nippon Steel Corporation
    Inventors: Hiroaki Sakamoto, Toshio Yamada, Takashi Sato
  • Patent number: 6420042
    Abstract: The present invention provides a low iron-loss Fe-based amorphous alloy thin strip having an ultrathin oxide layer with a controlled thickness and/or a segregated layer containing either or both P and S at the lower section of an ultrathin oxide layer, as well as an Fe-based amorphous alloy thin strip fabricated with an ultrathin oxide layer with a controlled structure on the thin strip surface, wherein the ultrathin oxide layer is formed with a two-layer structure on the thin strip surface to reduce iron loss. Specifically, there is provided an Fe-based amorphous alloy thin strip characterized by being a quenched metal thin strip obtained by ejecting a molten metal onto a moving substrate through a casting nozzle with a slot-shaped opening and quenching it to solidity, and by having ultrathin oxide layer with a thickness of from 5 nm to 20 nm on at least one surface of the thin strip.
    Type: Grant
    Filed: September 24, 1999
    Date of Patent: July 16, 2002
    Assignee: Nippon Steel Corporation
    Inventors: Hiroaki Sakamoto, Toshio Yamada, Yoshiharu Inoue
  • Patent number: 6416879
    Abstract: The object of the present invention is to provide an Fe-based amorphous alloy thin strip capable of realizing an excellent soft magnetic property for use in alternating current applications while keeping a high magnetic flux density even in a composition range with a high Fe content, and an Fe-based amorphous alloy thin strip with which a core having an excellent soft magnetic property can be manufactured, even if there occurs a temperature difference among different portions of the core during annealing. The present invention is an Fe-based amorphous alloy thin strip having a high magnetic flux density, consisting of the main component elements of Fe, Si, B, C, and P and unavoidable impurities, characterized by having: a composition, in atomic %, of 82<Fe≦90, 2≦Si<4, 5<B≦16, 0.02≦C≦4, and 0.2≦P≦12; Bs of 1.74 T or more after annealing; B80 exceeding 1.5 T; and a low core loss of 0.12 W/kg or less.
    Type: Grant
    Filed: September 21, 2001
    Date of Patent: July 9, 2002
    Assignee: Nippon Steel Corporation
    Inventors: Hiroaki Sakamoto, Yuichi Sato
  • Patent number: 6073493
    Abstract: In a method of diagnosing the fatigue life of structural steelwork according to the present invention, a Barkhausen noise measurement is performed under the condition of 5 .mu.m.ltoreq.d.ltoreq.1 mm where d is the detection depth of Barkhausen noise, by using a magnetic head constituted by an air-core coil detection head and a magnetic excitation head obtained by winding a copper wire such as an enameled wire on a U-shaped core made of a soft magnetic material such as a silicon steel sheet or an amorphous magnetic material. The degree of fatigue damage of a target measurement portion is diagnosed using the root-mean-square (RMS) voltage or voltage amplitude value of the Barkhausen noise. According to this method, the degree of fatigue and degradation by stress and strain in the structural steelwork can be accurately diagnosed prior to development of cracking without any limitation on diagnostic locations.
    Type: Grant
    Filed: January 5, 1998
    Date of Patent: June 13, 2000
    Assignee: Nippon Steel Corporation
    Inventors: Hiroaki Sakamoto, Toru Inaguma, Yasuhiro Nakata, Mitsuhiko Yazaki
  • Patent number: 6060172
    Abstract: The present invention relates to a rapidly quenched metal strip used as a core material for transformers, magnetic shields, choke coils, etc., and to an Fe-based rapidly quenched metal strip having a strip thickness exceeding 20 .mu.m and up to 70 .mu.m, wherein nonmetallic inclusions contained in said metal strip have a maximum particle size up to 50% of the strip thickness, and densities of the nonmetallic inclusions are up to 10 nonmetallic inclusions/mm.sup.3 for nonmetallic inclusions having a particle size exceeding 10 .mu.m and up to 50% of the strip thickness, up to 3.times.10.sup.3 nonmetallic inclusions/mm.sup.3 for nonmetallic inclusions having a particle size of at least 3 .mu.m to up to 10 .mu.m, and up to 5.times.10.sup.5 nonmetallic inclusions/mm.sup.3 for nonmetallic inclusions having a particle size of at least 0.3 .mu.m to less than 3 .mu.m, and showing the following average value <.epsilon..sub.f > of a bending fracture strain .epsilon..sub.
    Type: Grant
    Filed: April 10, 1998
    Date of Patent: May 9, 2000
    Assignee: Nippon Steel Corporation
    Inventors: Yoshiharu Inoue, Hiroaki Sakamoto
  • Patent number: 5958153
    Abstract: An amorphous metal alloy strip having enhanced magnetic properties consisting essentially of a composition mainly composed of Fe, Si, B, C and P having the formula (Fe.sub.a Si.sub.b B.sub.c C.sub.d).sub.100-x P.sub.x, wherein "a", "b", "c" and "d" are atomic percentages ranging from 70 to 86, 1 to 19, 7 to 20 and 0.02 to 4, respectively, with the proviso that the sum of "a", "b", "c" and "d" is equal to 100, and "x" is a weight percentage ranging from 0.003 to 0.1, said alloy strip having a thickness of 40 to 90 .mu.m and a width of not less than 20 mm. This amorphous metal alloy strip can be produced by a sinle-roll or twin-roll process under a specific cooling condition.
    Type: Grant
    Filed: April 10, 1996
    Date of Patent: September 28, 1999
    Assignee: Nippon Steel Corporation
    Inventors: Hiroaki Sakamoto, Yuichi Sato, Toshio Yamada
  • Patent number: 5835537
    Abstract: A multiplex transmission apparatus, having a communication control circuit for carrying out transmit-receive control of a frame of data transmitted through a bus, and an output port for outputting data in frame received by the communication control circuit. The multiplex transmission apparatus is operated by a power supply voltage supplied from a power supply circuit to perform data communication with another multiplex transmission apparatus via a bus. First and second low voltage detection circuits, when detecting preset voltage values V.sub.L and V.sub.R of a power supply voltage, reset the communication control circuit and the output port. This multiplex transmission apparatus keeps the output of the output port in a normal condition despite relatively small variations in the power supply voltage (i,e., where V.sub.L .gtoreq.power supply voltage>V.sub.R).
    Type: Grant
    Filed: March 30, 1995
    Date of Patent: November 10, 1998
    Assignee: The Furukawa Electric Co., Ltd.
    Inventors: Eiji Ichii, Hiroo Moriue, Yutaka Matsuda, Hiroaki Sakamoto, Yoshikazu Nobutoki
  • Patent number: 5825749
    Abstract: A multiplex data communication system including a number of communication nodes interconnected through a transmission path, each of which includes a data transmitting/receiving circuit providing a reception signal representative of normal data reception from another communication node and a transmission signal representative of normal data transmission therefrom, and a data operation circuit for controlling an electronic equipment unit associated with each communication node based on the data from the other communication node and generating the data relating to each communication node which is transmitted by the data transmitting/receiving circuit, the data operation circuit making a judgement of normality of a data communication function of each communication node based on at least one of the data reception signal and data transmission signal.
    Type: Grant
    Filed: April 1, 1996
    Date of Patent: October 20, 1998
    Assignee: Mazda Motor Corporation
    Inventors: Koji Terayama, Seiji Hirano, Toshiaki Kawanishi, Toshifumi Ikeda, Hiroaki Sakamoto
  • Patent number: 5740853
    Abstract: To solve the problem of capturing the strip leading edge for improving the success rate of coiling and to eliminate the complicated recovery of the coiled strip for improving the productivity, a process of online-coiling a quench-solidified magnetic strip produced by ejecting a liquid metal or metal alloy onto a moving cooled substrate comprises the step of rotating a coiling roll having a magnetized surface to coil the strip therearound, at a coiling roll surface speed within the range of not less than 90% and less than 100% of a moving speed of the substrate, upon starting the coiling.
    Type: Grant
    Filed: January 11, 1996
    Date of Patent: April 21, 1998
    Assignee: Nippon Steel Corporation
    Inventors: Soshichi Tsuchihashi, Masayoshi Tatsukawa, Minoru Yamate, Hiroaki Sakamoto, Yuichi Sato
  • Patent number: 5654511
    Abstract: A rail axial-force measuring method and an axial-force measurable rail which eliminate the effects of residual stresses existing in a rail and thus enables an axial force acting on the rail to be measured quickly and accurately are provided. The rail is provided with a stress sensing portion which is magnetized by a magnetizing head, and changes in the magnetization of the stress sensing portion are detected by a detection head as a voltage signal from which an axial force acting on the rail is measured. Preferably, the voltage signal is a Barkhausen noise signal and, also preferably, the stress sensing portion is constructed from a portion formed by first locally heating the rail into a .gamma.-phase region, and then causing cementite to precipitate by heat treatment at a temperature lower than the .gamma.-phase region. The axial-force measurable rail including the above-described stress sensing portion is also provided.
    Type: Grant
    Filed: November 30, 1995
    Date of Patent: August 5, 1997
    Assignee: Nippon Steel Corporation
    Inventors: Kazuo Sugino, Hiroaki Sakamoto, Toru Inaguma
  • Patent number: 5652394
    Abstract: A stress sensor, which, in use, is attached to a measuring object and generates Barkhausen signals, for measuring a stress applied to the object, wherein the Barkhausen signals have a reduced temperature dependence. The stress sensor is characterized by comprising a steel material having such a texture that a granular carbide comprising: element M wherein M represents at least one element selected from Fe, Al, B, Co, Cr, Mn, Mo, Nb, Ni, Si, Sn, Ti, U, V, W, and Zr; and C has been precipitated in the interior of ferrite grains. Preferably, the average grain diameter of the granular carbide precipitated in the texture is 0.05 to 1.0 .mu.m, and the standard deviation in grain size distribution of the granular carbide is 0.14 to 2.0 .mu.m. In another preferred embodiment, the average grain diameter of the granular carbide is more than 1.0 .mu.m and 3.0 .mu.m or less. Still preferably, the carbide is an M.sub.3 C compound.
    Type: Grant
    Filed: November 30, 1995
    Date of Patent: July 29, 1997
    Assignee: Nippon Steel Corporation
    Inventors: Kazuo Sugino, Hiroaki Sakamoto, Toru Inaguma
  • Patent number: 5565773
    Abstract: An arrangement of the magnetic detection and excitation head has an excitation head with a U-shaped excitation core of soft magnetic material forming two legs, each having an end plane facing a surface of a measured object, and an excitation coil wound on the core excitable by a low frequency current; and a detection head with a rod-shaped detection core of non-magnetic or soft magnetic material and a detection coil wound thereon. An end plane of the detection core which is to be close to the surface of the object, and the end planes of the two legs of the excitation core are arranged such that the end plane of the detection core is between the end planes of the two legs and all the end planes are substantially on a common flat plane.
    Type: Grant
    Filed: November 4, 1994
    Date of Patent: October 15, 1996
    Assignee: Nippon Steel Corporation
    Inventors: Toru Inaguma, Hiroaki Sakamoto