Patents by Inventor Makoto Hobo
Makoto Hobo 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: 20150083279Abstract: A nitrocarburized crankshaft member made of a steel having essentially ferrite and perlite, and at least a portion of a steel surface thereof having a ferrite surface area of 50% or greater that is imparted with a nitrocarburized hard layer. The steel consists of C, Si, Mn, Cu, Ni, and Cr as required elements and Mo, N, s-Al, Ti, Pb, Bi, and Ca as optional elements that may be included, and Fe and inevitable impurities. C is within a range of 0.25 to 0.32%. The nitrocarburized crankshaft member includes a thickness of a surface compound layer of the nitrocarburized hard layer of 10 to 35 ?m that is formed during establishment of a diffusion depth of a nitrogen diffusion zone below the surface compound layer of 700 ?m or greater.Type: ApplicationFiled: November 26, 2014Publication date: March 26, 2015Applicants: DAIDO STEEL CO., LTD., HONDA MOTOR CO., LTD.Inventors: Isamu SAITO, Yoshihiro TAKITANI, Shinichiro KATO, Makoto HOBO, Keiichiro KAMIYA, Takahiro MIYAZAKI, Takashi KANO
-
Patent number: 8911566Abstract: A nitrocarburized crankshaft member made of a steel that includes C in an amount by weight of 0.25 to 0.32% as a required element and an optional element that may be included, and Fe and inevitable impurities in a remaining portion. The steel-made crankshaft member mainly includes ferrite and perlite, wherein at least a portion of the steel surface thereof having a ferrite surface area of 50% or greater is imparted with a nitrocarburized hard layer. The nitrocarburized hard layer includes a surface compound layer suppressed to a thickness of 10 to 35 ?m, and a nitrogen diffusion zone below the surface compound layer having a diffusion depth of 700 ?m or greater. The steel includes C, Si, Mn, Cu, Ni, and Cr as the required elements and Mo, N, s-Al, and Ti as the optional elements.Type: GrantFiled: December 2, 2010Date of Patent: December 16, 2014Assignees: Honda Motor Co., Ltd., Daido Steel Co., Ltd.Inventors: Isamu Saito, Yoshihiro Takitani, Shinichiro Kato, Makoto Hobo, Keiichiro Kamiya, Takahiro Miyazaki, Takashi Kano
-
Patent number: 8685177Abstract: The invention relates to a crankshaft member having high fatigue strength and good bending correctability, and its method of manufacture. The steel made crankshaft member mainly consists of a two-phase structure of ferrite and perlite. The steel includes C, Ni, Mn, and Cr as required elements and Si, Cu, Mo, Ti, V, Nb, Ca, and S as optional elements that may be included, in the amounts of C within the range of 0.20 to 0.50 wt %, Si within the range of 0 to 0.6 wt %, Mn within the range of 0.5 to 1.5 wt %, Cu within the range of 0 to 0.7 wt %, Ni within the range of 0.05 to 1.5 wt %, Cr within the range of 0.05 to 0.45 wt %, and Mo within the range of 0 to 0.5 wt % to satisfy the condition 115?70C+8Si+23Mn+11Cu+128Cr+83Mo?50. A portion of the member surface is provided at least with a hard nitride layer having an average hardness within the range of 300 to 450 HV. Lamellar spacing of the perlite is 0.3 ?m or less.Type: GrantFiled: December 3, 2009Date of Patent: April 1, 2014Assignees: Honda Motor Co., Ltd., Daido Steel Co., Ltd.Inventors: Isamu Saito, Yoshihiro Takitani, Shinichiro Kato, Makoto Hobo, Keiichiro Kamiya, Takahiro Miyazaki, Takashi Kano
-
Publication number: 20110132138Abstract: A nitrocarburized crankshaft member made of a steel that includes C in an amount by weight of 0.25 to 0.32% as a required element and an optional element that may be included, and Fe and inevitable impurities in a remaining portion. The steel-made crankshaft member mainly includes ferrite and perlite, wherein at least a portion of the steel surface thereof having a ferrite surface area of 50% or greater is imparted with a nitrocarburized hard layer. The nitrocarburized hard layer includes a surface compound layer suppressed to a thickness of 10 to 35 ?m, and a nitrogen diffusion zone below the surface compound layer having a diffusion depth of 700 ?m or greater. The steel includes C, Si, Mn, Cu, Ni, and Cr as the required elements and Mo, N, s-Al, and Ti as the optional elements.Type: ApplicationFiled: December 2, 2010Publication date: June 9, 2011Applicants: HONDA MOTOR CO., LTD., DAIDO STEEL CO., LTD.Inventors: Isamu SAITO, Yoshihiro TAKITANI, Shinichiro KATO, Makoto HOBO, Keiichiro KAMIYA, Takahiro MIYAZAKI, Takashi KANO
-
Publication number: 20100139451Abstract: The invention relates to a crankshaft member having high fatigue strength and good bending correctability, and its method of manufacture. The steel made crankshaft member mainly consists of a two-phase structure of ferrite and perlite. The steel includes C, Ni, Mn, and Cr as required elements and Si, Cu, Mo, Ti, V, Nb, Ca, and S as optional elements that may be included, in the amounts of C within the range of 0.20 to 0.50 wt %, Si within the range of 0 to 0.6 wt %, Mn within the range of 0.5 to 1.5 wt %, Cu within the range of 0 to 0.7 wt %, Ni within the range of 0.05 to 1.5 wt %, Cr within the range of 0.05 to 0.45 wt %, and Mo within the range of 0 to 0.5 wt % to satisfy the condition 115?70 C+8 Si+23 Mn+11 Cu+128 Cr+83 Mo?50. A portion of the member surface is provided at least with a hard nitride layer having an average hardness within the range of 300 to 450 HV. Lamellar spacing of the perlite is 0.3 ?m or less.Type: ApplicationFiled: December 3, 2009Publication date: June 10, 2010Applicants: HONDA MOTOR CO., LTD., DAIDO STEEL CO., LTD.Inventors: Isamu SAITO, Yoshihiro Takitani, Shinichiro Kato, Makoto Hobo, Keiichiro Kamiya, Takahiro Miyazaki, Takashi Kano
-
Publication number: 20070144619Abstract: A nitrocarburized microalloyed steel member consists of a microalloyed steel that includes a nitrocarburized layer on a surface, a cross-sectional structure of which steel except for the nitrocarburized layer includes a ferrite and pearlite structure. The microalloyed steel mainly consists of Fe and has a composition: C having a content of 0.30 mass % or more and 0.50 mass % or less; Si having a content of 0.05 mass % or more and 0.30 mass % or less; Mn having a content of 0.50 mass % or more and 1.00 mass % or less; S having a content of 0.03 mass % or more and 0.20 mass % or less; Cu having a content of 0.05 mass % or more and 0.60 mass % or less; Ni having a content of 0.02 mass % or more and 1.00 mass % or less; and Cr having a content of 0.05 mass % or more and 0.30 mass % or less. If the contents of the Cu, the Ni, and the Cr are represented by WCu, WNi, and WCr mass %, respectively, and composition parameters F1 and F2 are 185WCr+50WCu and 8+4WNi+1.Type: ApplicationFiled: May 22, 2006Publication date: June 28, 2007Inventors: Tetsuya Asai, Yoshihiro Takitani, Masaki Amano, Makoto Hobo, Kazuyoshi Kimura, Katsunori Takada
-
Patent number: 6764645Abstract: Disclosed is a steel for machine structural use having good machinability and chip-breakability as well as a method of producing the steel. The steel consists essentially of, by wt. %, C: 0.05-0.8%, Si: 0.01-2.0%, Mn: 0.1-3.5%, S: 0.01-0.2%, Al: 0.001-0.020%, Ca: 0.0005-0.02%, O: 0.0005-0.01% and N: 0.001-0.04%, and further, one or both of Ti: 0.002-0.010% and Zr: 0.002-0.025%, the balance being Fe and inevitable impurities. At production of the steel controlled deoxidization is conducted by operation meeting certain conditions so that at least a certain amount of “duplex inclusion” having a specific chemical composition may be formed, and Ti and/or Zr is added to precipitate finely dispersed MnS inclusion particles with nuclei of Ti-oxide and/or Zr-oxide. The finely dispersed MnS inclusions must share a determined part of the total sulfide inclusions.Type: GrantFiled: November 27, 2002Date of Patent: July 20, 2004Assignee: Diado Steel Co., Ltd.Inventors: Masakazu Hayaishi, Takashi Kano, Kazuhisa Ishida, Yutaka Kurebayashi, Makoto Hobo
-
Publication number: 20030178105Abstract: Disclosed is a steel for machine structural use having good machinability and chip-breakability as well as a method of producing the steel. The steel consists essentially of, by wt. %, C: 0.05-0.8%, Si: 0.01-2.0%, Mn: 0.1-3.5%, S: 0.01-0.2%, Al: 0.001-0.020%, Ca: 0.0005-0.02%, O: 0.0005-0.01% and N: 0.001-0.04%, and further, one or both of Ti: 0.002-0.010% and Zr: 0.002-0.025%, the balance being Fe and inevitable impurities. At production of the steel controlled deoxidization is conducted by operation meeting certain conditions so that at least a certain amount of “duplex inclusion” having a specific chemical composition may be formed, and Ti and/or Zr is added to precipitate finely dispersed MnS inclusion particles with nuclei of Ti-oxide and/or Zr-oxide. The finely dispersed MnS inclusions must share a determined part of the total sulfide inclusions.Type: ApplicationFiled: November 27, 2002Publication date: September 25, 2003Inventors: Masakazu Hayashi, Takashi Kano, Kazuhisa Ishida, Yutaka Kurebayashi, Makoto Hobo