Patents by Inventor Shohtaroh Hara
Shohtaroh Hara 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).
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Patent number: 11719138Abstract: The present invention addresses the problem of providing a sintered alloy valve guide capable of inhibiting valve adhesion even in a high-temperature environment. The problem can be solved by a sintered alloy valve guide impregnated with a lubricating oil including pores that are sealed on the valve guide outer circumferential surface. More particularly, the problem is solved by the sealing step of performing a sealing treatment of pores on the outer circumferential surface of a sintered body impregnated with a lubricating oil.Type: GrantFiled: April 27, 2021Date of Patent: August 8, 2023Assignee: TPR Co., Ltd.Inventors: Fumiya Ito, Shohtaroh Hara
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Patent number: 11686226Abstract: The present invention addresses the problem of providing a sintered alloy valve guide capable of inhibiting valve adhesion even in a high-temperature environment. The problem can be solved by a sintered alloy valve guide impregnated with a lubricating oil including pores that are sealed on the valve guide outer circumferential surface. More particularly, the problem is solved by the sealing step of performing a sealing treatment of pores on the outer circumferential surface of a sintered body impregnated with a lubricating oil.Type: GrantFiled: April 27, 2021Date of Patent: June 27, 2023Assignee: TPR Co., Ltd.Inventors: Fumiya Ito, Shohtaroh Hara
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Publication number: 20230127085Abstract: The present invention addresses the problem of providing a sintered alloy valve guide capable of inhibiting valve adhesion even in a high-temperature environment. The problem can be solved by a sintered alloy valve guide impregnated with a lubricating oil including pores that are sealed on the valve guide outer circumferential surface. More particularly, the problem is solved by the sealing step of performing a sealing treatment of pores on the outer circumferential surface of a sintered body impregnated with a lubricating oil.Type: ApplicationFiled: April 27, 2021Publication date: April 27, 2023Inventors: Fumiya Ito, Shohtaroh Hara
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Patent number: 10036287Abstract: The valve seat includes an iron-based sintered alloy subjected to oxidation treatment, which is obtained by subjecting an iron-based sintered alloy including: 4 mass % to 15 mass % of Co particles; and hard particles each containing at least one compound of an intermetallic compound, a carbide, a silicide, a nitride, or a boride that has one or more kinds of elements selected from group 4a to 6a elements in a periodic table, and having a hardness of from 600 HV to 1,600 HV to oxidation treatment, and which has an oxide mainly including triiron tetraoxide (Fe3O4) and cobalt oxide (CoO) formed on a surface and in an interior of the iron-based sintered alloy. The iron-based sintered alloy subjected to oxidation treatment has an area ratio of the oxide of from 5% to 25% in a cross section thereof in a state prior to installation on the cylinder head.Type: GrantFiled: July 26, 2016Date of Patent: July 31, 2018Assignee: TPR CO., LTD.Inventors: Yoshio Koyama, Shohtaroh Hara
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Patent number: 9581056Abstract: Provided is a valve seat having excellent strength and wear resistance. In a valve seat using an iron-based sintered alloy, an oxide mains composed of triiron tetroxide is formed by oxidation treatment on the surface and interior of the iron-based sintered alloy, and the average area ratio of the oxide mainly composed of triiron tetroxide in a cross section of the iron-based, sintered alloy in the state prior to installation on a cylinder head is 5 to 20%. Preferably, the iron-based sintered alloy contains hard particles formed from at least one compound of carbides, silicides, nitrides, borides, and intermetallic compounds containing one or more elements selected from groups 4a to 6a of the periodic table, and the average area ratio of the hard particles in the cross section of the iron-based sintered alloy in the state prior to installation on a cylinder head is 5 to 45%.Type: GrantFiled: June 14, 2012Date of Patent: February 28, 2017Assignee: TPR CO., LTD.Inventors: Yoshio Koyama, Fusanobu Hanada, Shohtaroh Hara
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Patent number: 9556761Abstract: The valve seat includes an iron-based sintered alloy subjected to oxidation treatment, which is obtained by subjecting an iron-based sintered alloy including: 4 mass % to 15 mass % of Co particles; and hard particles each containing at least one compound of an intermetallic compound, a carbide, a silicide, a nitride, or a boride that has one or more kinds of elements selected from group 4a to 6a elements in a periodic table, and having a hardness of from 600 HV to 1,600 HV to oxidation treatment, and which has an oxide mainly including triiron tetraoxide (Fe3O4) and cobalt oxide (CoO) formed on a surface and in an interior of the iron-based sintered alloy. The iron-based sintered alloy subjected to oxidation treatment has an area ratio of the oxide of from 5% to 25% in a cross section thereof in a state prior to installation on the cylinder head.Type: GrantFiled: September 5, 2013Date of Patent: January 31, 2017Assignee: TPR CO., LTD.Inventors: Yoshio Koyama, Shohtaroh Hara
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Publication number: 20160333456Abstract: The valve seat includes an iron-based sintered alloy subjected to oxidation treatment, which is obtained by subjecting an iron-based sintered alloy including: 4 mass % to 15 mass % of Co particles; and hard particles each containing at least one compound of an intermetallic compound, a carbide, a silicide, a nitride, or a boride that has one or more kinds of elements selected from group 4a to 6a elements in a periodic table, and having a hardness of from 600 HV to 1,600 HV to oxidation treatment, and which has an oxide mainly including triiron tetraoxide (Fe3O4) and cobalt oxide (CoO) formed on a surface and in an interior of the iron-based sintered alloy. The iron-based sintered alloy subjected to oxidation treatment has an area ratio of the oxide of from 5% to 25% in a cross section thereof in a state prior to installation on the cylinder head.Type: ApplicationFiled: July 26, 2016Publication date: November 17, 2016Inventors: Yoshio KOYAMA, Shohtaroh HARA
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Publication number: 20160201527Abstract: The valve seat includes an iron-based sintered alloy subjected to oxidation treatment, which is obtained by subjecting an iron-based sintered alloy including: 4 mass % to 15 mass % of Co particles; and hard particles each containing at least one compound of an intermetallic compound, a carbide, a silicide, a nitride, or a boride that has one or more kinds of elements selected from group 4a to 6a elements in a periodic table, and having a hardness of from 600 HV to 1,600 HV to oxidation treatment, and which has an oxide mainly including triiron tetraoxide (Fe3O4) and cobalt oxide (CoO) formed on a surface and in an interior of the iron-based sintered alloy. The iron-based sintered alloy subjected to oxidation treatment has an area ratio of the oxide of from 5% to 25% in a cross section thereof in a state prior to installation on the cylinder head.Type: ApplicationFiled: September 5, 2013Publication date: July 14, 2016Inventors: Yoshio KOYAMA, Shohtaroh HARA
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Publication number: 20150047596Abstract: Provided is a valve seat having excellent strength and wear resistance. In a valve seat using an iron-based sintered alloy, an oxide mains composed of triiron tetroxide is formed by oxidation treatment on the surface and interior of the iron-based sintered alloy, and the average area ratio of the oxide mainly composed of triiron tetroxide in a cross section of the iron-based, sintered alloy in the state prior to installation on a cylinder head is 5 to 20%. Preferably, the iron-based sintered alloy contains hard particles formed from at least one compound of carbides, silicides, nitrides, borides, and intermetallic compounds containing one or more elements selected from groups 4a to 6a of the periodic table, and the average area ratio of the hard particles in the cross section of the iron-based sintered alloy in the state prior to installation on a cylinder head is 5 to 45%.Type: ApplicationFiled: June 14, 2012Publication date: February 19, 2015Applicant: TPR CO., LTD.Inventors: Yoshio Koyama, Fusanobu Hanada, Shohtaroh Hara