Patents by Inventor Fumitaka Abukawa
Fumitaka Abukawa 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: 7575643Abstract: The invention provides a carburization treatment method in which the carburization treatment is conducted under a condition where an atmosphere within the furnace is maintained at a high carbon potential which is slightly blow a carbon solid solubility. Preferably, the internal pressure within the furnace is kept at 0.1 to 101 kPa, the hydrocarbon gas is one, two or more than two kinds of gases selected from the group consisting of C3H8, C3H6, C4H10, C2H2, C2H4, C2H6 and CH4, while the oxidative gas is an air, an O2 gas, or CO2 gas.Type: GrantFiled: March 28, 2002Date of Patent: August 18, 2009Assignee: Dowa Mining Co., Ltd.Inventors: Hisashi Ebihara, Jun Takahashi, Fumitaka Abukawa, Keiji Yokose, Hidetoshi Juryozawa
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Publication number: 20080073002Abstract: The invention provides a carburization treatment method in which a carburization treatment is conducted simultaneously with an operation of supplying a hydrocarbon gas and an oxidative gas into a furnace kept under a reduced pressure. Preferably, the internal pressure within the furnace is kept at 0.1 to 101 kPa, the hydrocarbon gas is one, two or more than two kinds of gases selected from the group consisting of C3H8, C3H6, C4H10, C2H2, C2H4, C2H6 and CH4, while the oxidative gas is an air, an O2 gas, or CO2 gas.Type: ApplicationFiled: September 10, 2007Publication date: March 27, 2008Applicant: DOWA THERMOTECH CO., LTD.Inventors: Fumitaka Abukawa, Hisashi Ebihara, Hidetoshi Juryozawa, Jun Takahashi, Keiji Yokose
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Patent number: 7276204Abstract: The invention provides a carburization treatment method in which a carburization treatment is conducted simultaneously with an operation of supplying a hydrocarbon gas and an oxidative gas into a furnace kept under a reduced pressure. Preferably, the internal pressure within the furnace is kept at 0.1 to 101 kPa, the hydrocarbon gas is one, two or more than two kinds of gases selected from the group consisting of C3H8, C3H6, C4H10, C2H2, C2H4, C2H6 and CH4, while the oxidative gas is an air, an O2 gas, or CO2 gas.Type: GrantFiled: March 28, 2002Date of Patent: October 2, 2007Assignee: Dowa Thermotech Co., Ltd.Inventors: Hisashi Ebihara, Jun Takahashi, Fumitaka Abukawa, Keiji Yokose, Hidetoshi Juryozawa
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Patent number: 7024916Abstract: A vacuum heat treatment furnace comprising a furnace shell, a casing arranged in an inner side of the furnace shell, a heat insulating layer consisting of a thick plate-like alumina-silica series ceramic fiber blanket and a thin plate-like alumina series ceramic material arranged in an inside of the casing, and a heater arranged in a heating room surrounded by the heat insulating layer.Type: GrantFiled: January 16, 2004Date of Patent: April 11, 2006Assignee: Dowa Mining Co., Ltd.Inventors: Hidetoshi Juryozawa, Keiji Yokose, Fumitaka Abukawa, Jun Takahashi, Hisashi Ebihara
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Publication number: 20040149006Abstract: A vacuum heat treatment furnace comprising a furnace shell, a casing arranged in an inner side of the furnace shell, a heat insulating layer consisting of a thick plate-like alumina-silica series ceramic fiber blanket and a thin plate-like alumina series ceramic material arranged in an inside of the casing, and a heater arranged in a heating room surrounded by the heat insulating layer.Type: ApplicationFiled: January 16, 2004Publication date: August 5, 2004Applicant: Dowa Mining Co., Ltd.Inventors: Hidetoshi Juryozawa, Keiji Yokose, Fumitaka Abukawa, Jun Takahashi, Hisashi Ebihara
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Patent number: 6709629Abstract: A vacuum heat treatment furnace comprising a furnace shell, a casing arranged in an inner side of the furnace shell, a heat insulating layer consisting of a thick plate-like alumina-silica series ceramic fiber blanket and a thin plate-like alumina series ceramic material arranged in an inside of the casing, and a heater arranged in a heating room surrounded by the heat insulating layer.Type: GrantFiled: March 28, 2002Date of Patent: March 23, 2004Assignee: Dowa Mining Co., Ltd.Inventors: Hidetoshi Juryozawa, Keiji Yokose, Fumitaka Abukawa, Jun Takahashi, Hisashi Ebihara
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Publication number: 20020189322Abstract: A vacuum heat treatment furnace comprising a furnace shell, a casing arranged in an inner side of the furnace shell, a heat insulating layer consisting of a thick plate-like alumina-silica series ceramic fiber blanket and a thin plate-like alumina series ceramic material arranged in an inside of the casing, and a heater arranged in a heating room surrounded by the heat insulating layer.Type: ApplicationFiled: March 28, 2002Publication date: December 19, 2002Applicant: Dowa Mining Co., Ltd.Inventors: Hidetoshi Juryozawa, Keiji Yokose, Fumitaka Abukawa, Jun Takahashi, Hisashi Ebihara
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Publication number: 20020179187Abstract: The invention provides a carburization treatment method in which a carburization treatment is conducted simultaneously with an operation of supplying a hydrocarbon gas and an oxidative gas into a furnace kept under a reduced pressure. Preferably, the internal pressure within the furnace is kept at 0.1 to 101 kPa, the hydrocarbon gas is one, two or more than two kinds of gases selected from the group consisting of C3H8, C3H6, C4H10, C2H2, C2H4/C2H6 and CH4, while the oxidative gas is an air, an O2 gas, or CO2 gas.Type: ApplicationFiled: March 28, 2002Publication date: December 5, 2002Inventors: Hisashi Ebihara, Jun Takahashi, Fumitaka Abukawa, Keiji Yokose, Hidetoshi Juryozawa
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Publication number: 20020179186Abstract: The invention provides a carburization treatment method in which the carburization treatment is conducted under a condition where an atmosphere within the furnace is maintained at a high carbon potential which is slightly blow a carbon solid solubility. Preferably, the internal pressure within the furnace is kept at 0.1 to 101 kPa, the hydrocarbon gas is one, two or more than two kinds of gases selected from the group consisting of C3H8, C3H6, C4H10, C2H2, C2H4, C2H6 and CH4, while the oxidative gas is an air, an O2 gas, or CO2 gas.Type: ApplicationFiled: March 28, 2002Publication date: December 5, 2002Inventors: Hisashi Ebihara, Jun Takahashi, Fumitaka Abukawa, Keiji Yokose, Hidetoshi Juryozawa
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Patent number: 5868871Abstract: Method and apparatus for carburizing, quenching and tempering workpieces, by which the step of carburizing can be incorporated into a machining and manufacturing process to be performed by an on-line machining and manufacturing system as one stage thereof, and by which high-quality treatment or processing can be achieved without occurrences of variation in quality among heat-treated products. In this apparatus, a preheating chamber (2), six carburizing chambers (5a to 5f), a cooling chamber (6), a reheating chamber (7), a quenching chamber (8) are placed around an intermediate chamber (4) having a transport device (12). Further, a high-frequency induction heating technique is used for heating each of major ones of the treatment or processing chambers. Moreover, a plasma carburizing method is performed in the carburizing chambers.Type: GrantFiled: June 2, 1997Date of Patent: February 9, 1999Assignee: Dowa Mining Co., Ltd.Inventors: Keiji Yokose, Fumitaka Abukawa, Hidetoshi Juryosawa, Jun Takahashi, Shinichi Takemoto, Hideki Inoue
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Patent number: 5795538Abstract: In a method for quenching metal parts, a quenching chamber is provided in which the quenching oil is continuously supplied from below the steel parts and circulated upward through the parts in a laminar flow. The circulation is accomplished by feeding the quenching oil onto the bottom of the quenching chamber of an auxiliary chamber surrounding it.Type: GrantFiled: August 28, 1996Date of Patent: August 18, 1998Assignee: Dowa Mining Co., Ltd.Inventors: Fumitaka Abukawa, Hitoshi Goi, Masahiko Watanabe, Shin Kurasawa, Hirofumi Kamisugi
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Patent number: 5795406Abstract: In a cementation method of metals in which hydrocarbon gas and oxidization gas are introduced into a heat treatment furnace, a small quantity of hydrocarbon gas of is introduced at a low pressure into the heat treatment furnace. The shift time and the gradient of the carbon potential varying toward a predetermined high or low level are controlled by increasing or decreasing the quantity of cementation gas and oxidization gas to be supplied to the furnace. After the carbon potential is reached to the high or low level, the carbon potential is maintained for a predetermined time period so as to prevent the deposited carbide from being bulked. In order to prevent the gas supply pipe from being choked with the soot of the hydrocarbon, oxidization gas of intermediate pressure is flushed into the gas supply pipe.Type: GrantFiled: December 19, 1996Date of Patent: August 18, 1998Assignee: Dowa Mining Co., Ltd.Inventors: Toshiyuki Kawamura, Hitoshi Goi, Fumitaka Abukawa
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Patent number: 4950334Abstract: In a gas carburizing method, a hydrocarbon gas and air are supplied to a furnace main body that carburizes a workpiece. The hydrocarbon gas and air react with one another in the furnace main body to generate an atmospheric gas having a carburizing property. The flow rate of the hydrocarbon gas to be supplied is maintained at a predetermined value. The flow rate of air to be supplied can be altered by adjusting the carbon potential of the atmospheric gas.A gas carburizing apparatus includes a furnace main body and load and unload chambers provided on two ends of the furnace main body. The load and unload chambers have combustion units. The combustion units communicate with the interiors of the load and unload chambers and burn a hydrocarbon gas. The combustion gas of the hydrocarbon gas is supplied to the load and unload chambers.Type: GrantFiled: April 11, 1988Date of Patent: August 21, 1990Assignees: Mitsubishi Jidosha Kogyo Kabushiki Kaisha, Tokyo Heat Treating Company, Ltd.Inventors: Nobuo Nishioka, Tadayoshi Juge, Yoshiaki Shimizu, Keishichi Namba, Hiroshi Shimura, Fumitaka Abukawa, Hitoshi Goi, Kazuyoshi Fujita, Yuichi Takasu