Patents by Inventor Takemori Takayama

Takemori Takayama 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: 11203803
    Abstract: A steel with high hardness and excellent toughness contains, in mass %, 0.55-1.10% C, 0.10-2.00% Si, 0.10-2.00% Mn, 0.030% or less P, 0.030% or less S, 1.10-2.50% Cr, and 0.010-0.10% Al, with the balance consisting of Fe and unavoidable impurities. The structure of the steel after quenching is a dual phase structure of martensitic structure and spheroidized carbide. Spheroidized cementite particles with an aspect ratio of 1.5 or less constitute at least 90% of all cementite particles. The proportion of the number of spheroidized cementite particles on the prior austenite grain boundaries to a total number of cementite particles is 20% or less.
    Type: Grant
    Filed: September 16, 2016
    Date of Patent: December 21, 2021
    Assignees: OSAKA UNIVERSITY, KOMATSU LTD.
    Inventors: Yoritoshi Minamino, Takemori Takayama, Koji Yamamoto, Yusuke Hiratsuka
  • Publication number: 20200165710
    Abstract: A steel with high hardness and excellent toughness contains, in mass %, 0.55-1.10% C, 0.10-2.00% Si, 0.10-2.00% Mn, 0.030% or less P, 0.030% or less S, 1.10-2.50% Cr, and 0.010-0.10% Al, with the balance consisting of Fe and unavoidable impurities. The structure of the steel after quenching is a dual phase structure of martensitic structure and spheroidized carbide. Spheroidized cementite particles with an aspect ratio of 1.5 or less constitute at least 90% of all cementite particles. The proportion of the number of spheroidized cementite particles on the prior austenite grain boundaries to a total number of cementite particles is 20% or less.
    Type: Application
    Filed: September 16, 2016
    Publication date: May 28, 2020
    Applicants: OSAKA UNIVERSITY, KOMATSU LTD.
    Inventors: Yoritoshi MINAMINO, Takemori TAKAYAMA, Koji YAMAMOTO, Yusuke HIRATSUKA
  • Patent number: 8679400
    Abstract: An iron-based sintered sliding material includes: a sintered structure which contains 10-50 wt. % copper and 1-15 wt. % carbon and has been formed by sintering a powder mixture obtained by mixing at least one of an Fe—Cu alloy powder containing copper in an amount which is the solid solubility or larger and is 5-50 wt. %, excluding 50 wt. %, and an Fe—Cu—C alloy powder containing copper in an amount which is the solid solubility or larger and is 5-50 wt. %, excluding 50 wt. %, and containing carbon in an amount of 0-5 wt. %, excluding 0 wt. %, with a graphite powder and at least one of a copper powder and a copper alloy powder; and graphite particles dispersed in the sintered sliding material in an amount of 1-14 wt. % or 3-50 vol. %.
    Type: Grant
    Filed: March 6, 2012
    Date of Patent: March 25, 2014
    Assignee: Komatsu Ltd
    Inventor: Takemori Takayama
  • Patent number: 8480820
    Abstract: A ferrous abrasion resistant sliding material and sliding member having improved seizing resistance, abrasion resistance and heat crack resistance are provided. The ferrous abrasion resistant sliding material has a parent phase taking the form of at least either one of a ferrite phase or a martensite phase, wherein the parent phase contains Al of 1.5 to 20 wt %, and at least either carbide, which may be selected from one or more types, of cementite, Cr7C3-type carbide, Fe3M3C-type carbide and MC-type carbide, or graphite is dispersed therein.
    Type: Grant
    Filed: April 1, 2005
    Date of Patent: July 9, 2013
    Assignee: Komatsu Ltd.
    Inventor: Takemori Takayama
  • Patent number: 8404356
    Abstract: A contact material which provides improved wear resistance as well as reduced adhesion utilizing the features of an intermetallic compound having an ordered phase, with the intention of (i) improving the seizure resistance and/or wear resistance of an implement bearing which slides under low-speed, high-surface-pressure conditions and is susceptible to lubricant starvation; (ii) preventing abnormal noises; and (iii) achieving prolonged greasing intervals. The contact material contains 10% by volume or more a metallic alloy phase having such a composition range that causes an order-disorder transition. The metallic alloy phase is a Fe base alloy phase containing one or more elements selected from the group consisting of Al, Si, Co and Ni.
    Type: Grant
    Filed: January 26, 2005
    Date of Patent: March 26, 2013
    Assignee: Komatsu, Ltd.
    Inventors: Takemori Takayama, Yoshikiyo Tanaka, Tetsuo Onishi
  • Patent number: 8283046
    Abstract: A ferrous sintered multilayer roll-formed bushing having a ferrous sintered sliding material layer which is sinter-bonded to a back metal steel, wherein the ferrous sintered sliding material layer is produced in such a manner that a Fe—C—Cu—Sn based sintered sliding material mixed powder containing at least carbon of 0.40 to 15 wt %, Cu of 13 to 40 wt % and Sn of 0.5 to 10 wt % is preliminarily sinter-bonded to said back metal steel and then finally sinter-bonded by a liquid-phase sintering at high temperatures higher than 1000° C. after bending into a roll.
    Type: Grant
    Filed: January 30, 2007
    Date of Patent: October 9, 2012
    Assignee: Komatsu Ltd.
    Inventor: Takemori Takayama
  • Patent number: 8257514
    Abstract: A ferrous seal sliding part excellent in heat crack resistance, seizing resistance and abrasion resistance is provided. The ferrous seal sliding part having a seal sliding surface, wherein the seal sliding surface has a martensite parent phase which forms a solid solution with carbon of 0.15 to 0.6 wt % and contains a first dispersion material of at least either cementite of 5 to 70% by volume or MC-type carbide of 0.1 to 10% by volume and a second dispersion material of at least either graphite of 1 to 15% by volume or Cu alloy phase of 1 to 20% by volume dispersed therein, with a total content of the first dispersion material and the second dispersion material being 5 to 70% by volume.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: September 4, 2012
    Assignee: Komatsu Ltd.
    Inventors: Takemori Takayama, Koji Yamada, Shigeo Otsuka
  • Publication number: 20120177528
    Abstract: An iron-based sintered sliding material includes: a sintered structure which contains 10-50 wt. % copper and 1-15 wt. % carbon and has been formed by sintering a powder mixture obtained by mixing at least one of an Fe—Cu alloy powder containing copper in an amount which is the solid solubility or larger and is 5-50 wt. %, excluding 50 wt. %, and an Fe—Cu—C alloy powder containing copper in an amount which is the solid solubility or larger and is 5-50 wt. %, excluding 50 wt. %, and containing carbon in an amount of 0-5 wt. %, excluding 0 wt. %, with a graphite powder and at least one of a copper powder and a copper alloy powder; and graphite particles dispersed in the sintered sliding material in an amount of 1-14 wt. % or 3-50 vol. %.
    Type: Application
    Filed: March 6, 2012
    Publication date: July 12, 2012
    Inventor: Takemori TAKAYAMA
  • Publication number: 20120160832
    Abstract: A gear part has a quench hardened layer around the teeth surface thereof. The gear part is made of a steel containing carbon of 0.43 to 1.2 wt %, and a relationship between a DI value and a module M (mm) of the gear part satisfies an expression of DI?0.12×M+0.2. An alloy element concentrates in the cementite phase in a pretreated steel, thereby causing concentration of the alloy element in the ferrite phase in the pretreated steel to decrease, and a rapid induction heating to A3 transformation temperature or Acm transformation temperature causes carbon of 0.3 to 0.8 wt % to diffuse and dissolve in the austenite phase, and the DI value is determined by using a concentration of the alloy element and a concentration of the carbon. The alloy element is one or more elements selected from the group consisting of Mn, Cr, Mo, V and the like.
    Type: Application
    Filed: March 5, 2012
    Publication date: June 28, 2012
    Inventor: Takemori TAKAYAMA
  • Patent number: 8083869
    Abstract: A ferrous seal sliding part excellent in heat crack resistance, seizure resistance and abrasion resistance is provided. The ferrous seal sliding part has a seal sliding surface, wherein the seal sliding surface has a quench hardened layer having a structure in which a martensite parent phase forms a solid solution with carbon of 0.15 to 0.6 wt % and contains cementite dispersed therein in a content of 3 to 50% by volume.
    Type: Grant
    Filed: February 25, 2005
    Date of Patent: December 27, 2011
    Assignee: Komatsu Ltd.
    Inventors: Takemori Takayama, Chikara Nakao
  • Patent number: 7998238
    Abstract: A sintered sliding member comprises a back metal (21a) and a ferrous sintered sliding body (20) which is sintering-bonded to the back metal (21a). The ferrous sintered sliding body (20) has martensite phase having a solid soluble carbon concentration of 0.15 to 0.5 wt % and contains carbide in a content of 5 to 50% by volume. The sintered sliding member is excellent in abrasion resistance, seizing resistance and heat crack resistance.
    Type: Grant
    Filed: July 30, 2004
    Date of Patent: August 16, 2011
    Assignee: Komatsu Ltd.
    Inventors: Takemori Takayama, Tetsuo Ohnishi, Kazuo Okamura
  • Patent number: 7967922
    Abstract: A ferrous abrasion resistant sliding material capable of improving seizing resistance, abrasion resistance and heat crack resistance is provided. The ferrous abrasion resistant sliding material has a martensite parent phase which forms a solid solution with carbon of 0.15 to 0.5 wt %, and the martensite parent phase contains one or more types of each special carbide of Cr, Mo, W and V dispersed therein in a total content of 10 to 50% by volume.
    Type: Grant
    Filed: December 30, 2009
    Date of Patent: June 28, 2011
    Assignee: Komatsu Ltd.
    Inventor: Takemori Takayama
  • Patent number: 7922836
    Abstract: A ferrous abrasion resistant sliding material capable of improving seizing resistance, abrasion resistance and heat crack resistance is provided. The ferrous abrasion resistant sliding material has a martensite parent phase which forms a solid solution with carbon of 0.15 to 0.5 wt %, and the martensite parent phase contains one or more types of each special carbide of Cr, Mo, W and V dispersed therein in a total content of 10 to 50% by volume.
    Type: Grant
    Filed: November 30, 2009
    Date of Patent: April 12, 2011
    Assignee: Komatsu Ltd.
    Inventor: Takemori Takayama
  • Publication number: 20100227188
    Abstract: An economic ferrous sintered multilayer roll-formed bushing, a producing method of the same and a connecting device are provided, in which a ferrous sintered sliding material layer is tightly sintered-bonded to a back metal steel, the ferrous sintered sliding material layer being intended to have low coefficient of friction, having excellent seizing resistance and abrasion resistance and providing self-lubricating property so as to prolong a lubrication interval or eliminate the necessity of lubricating. The ferrous sintered multilayer roll-formed bushing according to the present invention comprises: a back metal steel; a ferrous sintered sliding material layer sinter-bonded to the back metal steel; a diffusion layer of ferrous alloy particle formed at the vicinity of the bonding boundary between the ferrous sintered sliding material layer and the back metal steel; and a Cu alloy phase formed at the vicinity of the bonding boundary and extending in the direction of the bonding boundary.
    Type: Application
    Filed: January 30, 2007
    Publication date: September 9, 2010
    Inventor: Takemori Takayama
  • Publication number: 20100108199
    Abstract: A ferrous abrasion resistant sliding material capable of improving seizing resistance, abrasion resistance and heat crack resistance is provided. The ferrous abrasion resistant sliding material has a martensite parent phase which forms a solid solution with carbon of 0.15 to 0.5 wt %, and the martensite parent phase contains one or more types of each special carbide of Cr, Mo, W and V dispersed therein in a total content of 10 to 50% by volume.
    Type: Application
    Filed: December 30, 2009
    Publication date: May 6, 2010
    Inventor: Takemori Takayama
  • Patent number: 7691213
    Abstract: There is provided an inexpensive rolling element used under high interface pressure such as induction hardened gears, the rolling element being improved in the seizure resistance of its tooth flanks and having a temper hardness of HRC 50 or more at 300° C. To this end, the rolling element is made from a steel material containing at least 0.45 to 1.5 wt % C and one or more alloy elements selected from 0.1 to 0.5 wt % V and 0.3 to 1.5 wt % Cr, and has a rolling contact surface layer having a structure tempered at low temperature in which 2 to 18% by volume cementite disperses in a martensite parent phase formed by induction heating and cooling and containing 0.25 to 0.8 wt % carbon solid-dissolving therein.
    Type: Grant
    Filed: March 1, 2004
    Date of Patent: April 6, 2010
    Assignee: Komatsu Ltd.
    Inventors: Takemori Takayama, Masanari Furumoto, Chikara Nakao, Noriko Morioka
  • Patent number: 7691212
    Abstract: Various inexpensive rolling elements for use under high interface pressure such as induction hardened gears are provided, which have improved seizure resistance at tooth flanks and a temper hardness of HRC 50 or more at 300 ° C. To this end, a rolling element is made from a steel material which contains at least 0.5 to 1.5 wt % carbon and 0.2 to 2.0 wt % one or more alloy elements selected from V, Ti, Zr, Nb, Ta and Hf; and in which 0.4 to 4.0% by volume one or more compounds selected from the carbides, nitrides and carbonitrides of the above alloy elements and having an average particle diameter of 0.2 to 5 ?m are dispersed. In such a rolling element, the soluble carbon concentration of a martensite parent phase of a rolling contact surface layer is adjusted to 0.3 to 0.8 wt %, the martensite parent phase having been subjected to induction hardening and low temperature tempering, and one or more of the above carbides, nitrides and carbonitrides are dispersed in an amount of 0.4 to 4.
    Type: Grant
    Filed: March 1, 2004
    Date of Patent: April 6, 2010
    Assignee: Komatsu Ltd.
    Inventor: Takemori Takayama
  • Publication number: 20100074791
    Abstract: A ferrous abrasion resistant sliding material capable of improving seizing resistance, abrasion resistance and heat crack resistance is provided. The ferrous abrasion resistant sliding material has a martensite parent phase which forms a solid solution with carbon of 0.15 to 0.5 wt %, and the martensite parent phase contains one or more types of each special carbide of Cr, Mo, W and V dispersed therein in a total content of 10 to 50% by volume.
    Type: Application
    Filed: November 30, 2009
    Publication date: March 25, 2010
    Inventor: Takemori Takayama
  • Patent number: 7648773
    Abstract: To provide a thermal spray membrane contact material, contact member and contact part and an apparatus to which they are applied, showing excellent seizure resistance and wear resistance even under high surface pressure/low speed sliding, high speed/high temperature sliding, or high surface pressure/high speed sliding.
    Type: Grant
    Filed: July 2, 2007
    Date of Patent: January 19, 2010
    Assignee: Komatsu Ltd.
    Inventors: Takemori Takayama, Tetsuo Ohnishi, Kazuo Okamura
  • Patent number: 7641747
    Abstract: A rolling member excellent in pitting strength, spalling strength and bending strength of dedendum has a first quench hardened layer 1 which is formed on a surface layer of the rolling member and has a parent phase taking the form of martensite phase which forms a solid solution with carbon of 0.35 to 0.8 wt %, and a second quench hardened layer 2 which is formed at a deeper layer under the first quench hardened layer and has a parent phase containing at least either one of martensite phase or bainite phase which forms a solid solution with carbon of 0.07 to 0.3 wt % and contains cementite dispersed therein in a content of 2 to 20% by volume.
    Type: Grant
    Filed: December 26, 2007
    Date of Patent: January 5, 2010
    Assignee: Komatsu Ltd.
    Inventor: Takemori Takayama