Patents by Inventor Kenji Yumoto

Kenji Yumoto 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).

  • Publication number: 20220152708
    Abstract: A cBN sintered compact comprising a cubic boron nitride and a ceramic binder phase, wherein a cubic C-containing Ta compound in an amount of 1.0 to 15.0 vol % is dispersed in the ceramic binder phase and has a mean particle diameter of 50 to 500 nm.
    Type: Application
    Filed: March 4, 2020
    Publication date: May 19, 2022
    Applicant: MITSUBISHI MATERIALS CORPORATION
    Inventors: Ryota Takei, Shiro Oguchi, Masashi Momma, Kenji Yumoto
  • Publication number: 20220144709
    Abstract: A cBN-based ultra-high pressure sintered body contains cBN particles and a binder phase. The binder phase contains at least one of a nitride or oxide of Al or a nitride, carbide, or carbonitride of Ti, and a metal boride having an average particle diameter of 20 to 300 nm is dispersed in an amount of 0.1 to 5.0 vol % in the binder phase. The metal boride includes a metal boride (B) containing at least one of Nb, Ta, Cr, Mo, and W as a metal component and containing no Ti and a metal boride (A) containing only Ti as a metal component. In a case where a ratio (vol %) of the metal boride (A) in the metal boride is represented by Va and a ratio (vol %) of the metal boride (B) is represented by Vb, a ratio of Vb/Va is 0.1 to 1.0.
    Type: Application
    Filed: February 27, 2020
    Publication date: May 12, 2022
    Applicant: MITSUBISHI MATERIALS CORPORATION
    Inventors: Masashi Momma, Shiro Oguchi, Ryota Takei, Kenji Yumoto
  • Patent number: 10883166
    Abstract: The present invention is directed to a surface-coated cubic boron nitride sintered material tool including a cBN substrate and a hard coating layer formed on a surface of the cBN substrate and having an alternate laminated structure of A layer and B layer. The cBN substrate (sintered material) includes: a Ti compound, WC, AlN, TiB2, Al2O3, and cBN. The A layer has a composition of (Ti1-xAlx)N (0.4?x?0.7 in terms of atomic ratio). The B layer has a composition of (Cr1-y-zAlyMz)N (0.03?y?0.4 and 0?z?0.05 in terms of atomic ratio). A plastic deformation work ratio of the B layer is 0.35 to 0.50.
    Type: Grant
    Filed: December 22, 2016
    Date of Patent: January 5, 2021
    Assignee: MITSUBISHI MATERIALS CORPORATION
    Inventors: Takuya Maekawa, Masakuni Takahashi, Shun Sato, Kenji Yumoto
  • Patent number: 10744569
    Abstract: The present invention is directed to a surface-coated cubic boron nitride sintered material tool including a cBN substrate and a hard coating layer formed on a surface of the cBN substrate and having an alternate laminated structure of A layer and B layer. A peak of the grain size distribution of cBN grains in the cBN sintered material is present within a range of a grain size from 0.50 to 1.00 ?m. The A layer has a composition of (Ti1-xAlx)N (0.4?x?0.7 in an atomic ratio). The B layer has a composition of (Cr1-y-zAlyMz)N (0.03?y?0.6 and 0?z?0.05 in an atomic ratio). An X-ray diffraction peak of a (200) plane is present at a position of a diffraction angle of 43.6 plus or minus 0.1 degrees, and a plastic deformation work ratio of the B layer is 0.35 to 0.50.
    Type: Grant
    Filed: March 2, 2017
    Date of Patent: August 18, 2020
    Assignee: MITSUBISHI MATERIALS CORPORATION
    Inventors: Takuya Maekawa, Masakuni Takahashi, Shun Sato, Kenji Yumoto
  • Patent number: 10406654
    Abstract: The present application is a new improvement in the fine-grained cubic Boron Nitride sintered compact which may be employed to manufacture a cutting tool. The compact contains at least 80 vol % cBN and is sintered under HPHT conditions. The invention has lower levels of unreacted cobalt in the final sintered material than conventions materials. The invention has proved beneficial in the machining of ferrous metal alloys such as sintered metal alloys.
    Type: Grant
    Filed: October 25, 2017
    Date of Patent: September 10, 2019
    Assignee: DIAMOND INNOVATIONS, INC.
    Inventors: Lawrence Thomas Dues, Kenji Yumoto
  • Publication number: 20190118344
    Abstract: The present application is a new improvement in the fine-grained cubic Boron Nitride sintered compact which may be employed to manufacture a cutting tool. The compact contains at least 80 vol % cBN and is sintered under HPHT conditions. The invention has lower levels of unreacted cobalt in the final sintered material than conventions materials. The invention has proved beneficial in the machining of ferrous metal alloys such as sintered metal alloys.
    Type: Application
    Filed: October 25, 2017
    Publication date: April 25, 2019
    Inventors: Lawrence Thomas DUES, Kenji YUMOTO
  • Publication number: 20190111495
    Abstract: The present invention is directed to a surface-coated cubic boron nitride sintered material tool including a cBN substrate and a hard coating layer formed on a surface of the cBN substrate and having an alternate laminated structure of A layer and B layer. A peak of the grain size distribution of cBN grains in the cBN sintered material is present within a range of a grain size from 0.50 to 1.00 ?m. The A layer has a composition of (Ti1-xAlx)N (0.4?x?0.7 in an atomic ratio). The B layer has a composition of (Cr1-y-zAlyMz)N (0.03?y?0.6 and 0?z?0.05 in an atomic ratio). An X-ray diffraction peak of a (200) plane is present at a position of a diffraction angle of 43.6 plus or minus 0.1 degrees, and a plastic deformation work ratio of the B layer is 0.35 to 0.50.
    Type: Application
    Filed: March 2, 2017
    Publication date: April 18, 2019
    Applicant: MITSUBISHI MATERIALS CORPORATION
    Inventors: Takuya MAEKAWA, Masakuni TAKAHASHI, Shun SATO, Kenji YUMOTO
  • Patent number: 10252379
    Abstract: A cutting tool including a cutting edge part made of cBN sintered material bonded through a brazing material for bonding and a cutting tool body made of WC-based cemented carbide is provided. In the cutting tool, the cutting edge part made of cBN sintered material and the cutting tool body made of WC-based cemented carbide are brazed by using a blazing material for bonding including: 35-40% of Ti in a mass ratio; 35-40% of Zr in a mass ratio; 5-15% of Ni in a mass ratio; and the Cu balance including inevitable impurities.
    Type: Grant
    Filed: December 22, 2014
    Date of Patent: April 9, 2019
    Assignee: MITSUBISHI MATERIALS CORPORATION
    Inventors: Makoto Igarashi, Tadakazu Ohashi, Kenji Yumoto, Hiroyasu Shimizu
  • Patent number: 10202309
    Abstract: A cBN sintered material cutting tool is provided. The cBN cutting tool includes a cutting tool body, which is a sintered material including cBN grains and a binder phase, wherein the sintered material comprises: the cubic boron nitride grains in a range of 40 volume % or more and less than 60 volume %; and Al in a range from a lower limit of 2 mass % to an upper limit Y, satisfying a relationship, Y=?0.1X+10, Y and X being an Al content in mass % and a content of the cubic boron nitride grains in volume %, respectively, the binder phase comprises: at least a Ti compound; Al2O3; and inevitable impurities, the Al2O3 includes fine Al2O3 grains with a diameter of 10 nm to 100 nm dispersedly formed in the binder phase, and there are 30 or more of the fine Al2O3 grains generated in an area of 1 ?m×1 ?m in a cross section of the binder phase.
    Type: Grant
    Filed: March 27, 2015
    Date of Patent: February 12, 2019
    Assignee: MITSUBISHI MATERIALS CORPORATION
    Inventors: Kenji Yumoto, Yosuke Miyashita
  • Publication number: 20190017162
    Abstract: The present invention is directed to a surface-coated cubic boron nitride sintered material tool including a cBN substrate and a hard coating layer formed on a surface of the cBN substrate and having an alternate laminated structure of A layer and B layer. The cBN substrate (sintered material) includes: a Ti compound, WC, AlN, TiB2, Al2O3, and cBN. The A layer has a composition of (Ti1-xAlx)N (0.4?x?0.7 in terms of atomic ratio). The B layer has a composition of (Cr1-y-zAlyMz)N (0.03?y?0.4 and 0?z?0.05 in terms of atomic ratio). A plastic deformation work ratio of the B layer is 0.35 to 0.50.
    Type: Application
    Filed: December 22, 2016
    Publication date: January 17, 2019
    Applicant: MITSUBISHI MATERIALS CORPORATION
    Inventors: Takuya MAEKAWA, Masakuni TAKAHASHI, Shun SATO, Kenji YUMOTO
  • Publication number: 20170101346
    Abstract: A cBN sintered material cutting tool is provided. The cBN cutting tool includes a cutting tool body, which is a sintered material including cBN grains and a binder phase, wherein the sintered material comprises: the cubic boron nitride grains in a range of 40 volume % or more and less than 60 volume %; and Al in a range from a lower limit of 2 mass % to an upper limit Y, satisfying a relationship, Y=?0.1X+10, Y and X being an Al content in mass % and a content of the cubic boron nitride grains in volume %, respectively, the binder phase comprises: at least a Ti compound; Al2O3; and inevitable impurities, the Al2O3 includes fine Al2O3 grains with a diameter of 10 nm to 100 nm dispersedly formed in the binder phase, and there are 30 or more of the fine Al2O3 grains generated in an area of 1 ?m×1 ?m in a cross section of the binder phase.
    Type: Application
    Filed: March 27, 2015
    Publication date: April 13, 2017
    Applicant: MITSUBISHI MATERIALS CORPORATION
    Inventors: Kenji YUMOTO, Yosuke MIYASHITA
  • Publication number: 20160318132
    Abstract: A cutting tool including a cutting edge part made of cBN sintered material bonded through a brazing material for bonding and a cutting tool body made of WC-based cemented carbide is provided. In the cutting tool, the cutting edge part made of cBN sintered material and the cutting tool body made of WC-based cemented carbide are brazed by using a blazing material for bonding including: 35-40% of Ti in a mass ratio; 35-40% of Zr in a mass ratio; 5-15% of Ni in a mass ratio; and the Cu balance including inevitable impurities.
    Type: Application
    Filed: December 22, 2014
    Publication date: November 3, 2016
    Applicant: MITSUBISHI MATERIALS CORPORATION
    Inventors: Makoto IGARASHI, Tadakazu OHASHI, Kenji YUMOTO, Hiroyasu SHIMIZU
  • Patent number: 8063630
    Abstract: In testing thin-film magnetic heads, first, a back surface opposite to a medium facing surface of each of a plurality of thin-film magnetic heads is attached to a first surface of a first plate of a jig, the jig including the first plate of rubber having the first and second surfaces facing toward opposite directions, and a second plate greater in rigidity than the first plate and bonded to the second surface of the first plate. Next, the plurality of thin-film magnetic heads and the jig are mounted on a metal plate having a flat top surface, such that the medium facing surfaces of the thin-film magnetic heads touch the top surface of the metal plate. Next, heat-generating components of the plurality of thin-film magnetic heads mounted on the metal plate are energized.
    Type: Grant
    Filed: March 14, 2008
    Date of Patent: November 22, 2011
    Assignee: TDK Corporation
    Inventors: Takamitsu Kamimura, Masato Sugahara, Kenji Yumoto
  • Publication number: 20090231743
    Abstract: In testing thin-film magnetic heads, first, a back surface opposite to a medium facing surface of each of a plurality of thin-film magnetic heads is attached to a first surface of a first plate of a jig, the jig including the first plate of rubber having the first and second surfaces facing toward opposite directions, and a second plate greater in rigidity than the first plate and bonded to the second surface of the first plate. Next, the plurality of thin-film magnetic heads and the jig are mounted on a metal plate having a flat top surface, such that the medium facing surfaces of the thin-film magnetic heads touch the top surface of the metal plate. Next, heat-generating components of the plurality of thin-film magnetic heads mounted on the metal plate are energized.
    Type: Application
    Filed: March 14, 2008
    Publication date: September 17, 2009
    Applicant: TDK CORPORATION
    Inventors: Takamitsu Kamimura, Masato Sugahara, Kenji Yumoto
  • Patent number: 5624298
    Abstract: A jig used for machining a head piece aggregate includes a first jig member and a second jig member. The first jig member is provided with a mounting surface to which the head piece aggregate is bonded, and the second jig member includes a main body portion and a distortion-generating mechanism. The main body portion is linked to the first jig member so that the distortion-generating mechanism, provided at the main body portion, imparts distortion to the first jig member. Thus, distortion of the head piece aggregate that occurs after it is secured on to the jig can be corrected.
    Type: Grant
    Filed: April 6, 1995
    Date of Patent: April 29, 1997
    Assignee: TDK Corporation
    Inventor: Kenji Yumoto