Patents by Inventor Keita Naito
Keita Naito 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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Publication number: 20230333077Abstract: A composition analysis device for fuel gas containing inert gas and flammable gas includes: a heating value measurement device for measuring a heating value per unit amount of the fuel gas; a density measurement device for measuring a density of the fuel gas; and a control device including a composition calculation unit for calculating a composition of the fuel gas using the heating value measured by the heating value measurement device and the density measured by the density measurement device.Type: ApplicationFiled: October 25, 2021Publication date: October 19, 2023Inventors: Toshifumi SASAO, Keita NAITO, Akinori HAYASHI
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Patent number: 11725593Abstract: A gas turbine including a fuel gas supply system to supply fuel gas via a fuel piping to a gas turbine combustor, a pressure control valve installed halfway along the fuel piping, a flow control valve installed in the fuel piping at downstream of the pressure control valve, and a control device configured that in a case where a flow rate change occurs in the fuel gas flowing through the fuel gas supply system, along with a tendency of change in an opening degree of the pressure control valve or a pressure P1 at upstream of the pressure control valve, a command value of the flow rate of the fuel gas that is determined based on a demand value of a gas turbine load is adjusted so that the change is suppressed in the opening degree of the pressure control valve or the pressure P1.Type: GrantFiled: September 16, 2021Date of Patent: August 15, 2023Assignee: Mitsubishi Heavy Industries, Ltd.Inventors: Tatsuya Hagita, Keita Naito, Mitsuhiro Karishuku, Masaya Kato, Satoshi Tanimura
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Patent number: 11493206Abstract: Provided is a gas turbine combustor that can achieve improvement of the combustion stability. A gas turbine combustor includes a pilot burner of the diffusion combustion type, a pilot flow control valve that regulates a flow rate of fuel to be supplied to the pilot burner, a main burner of the premix combustion type arranged on an outer circumference side of the pilot burner, main flow control valves that regulate flow rates of fuel to be individually supplied to burner sectors into which the main burner is sectioned in a circumferential direction, and a controller configured to control the pilot flow control valve and the main flow control valves. The controller controls the main flow control valves such that, when fuel is to be supplied to all the burner sectors, a difference in fuel flow rate occurs between at least one burner sector and the other burner sectors among the burner sectors.Type: GrantFiled: April 29, 2021Date of Patent: November 8, 2022Assignee: Mitsubishi Heavy Industries, Ltd.Inventors: Yasuhiro Wada, Kazuki Abe, Akinori Hayashi, Keita Naito
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Publication number: 20220099033Abstract: A gas turbine including a fuel gas supply system to supply fuel gas via a fuel piping to a gas turbine combustor, a pressure control valve installed halfway along the fuel piping, a flow control valve installed in the fuel piping at downstream of the pressure control valve, and a control device configured that in a case where a flow rate change occurs in the fuel gas flowing through the fuel gas supply system, along with a tendency of change in an opening degree of the pressure control valve or a pressure P1 at upstream of the pressure control valve, a command value of the flow rate of the fuel gas that is determined based on a demand value of a gas turbine load is adjusted so that the change is suppressed in the opening degree of the pressure control valve or the pressure P1.Type: ApplicationFiled: September 16, 2021Publication date: March 31, 2022Inventors: Tatsuya Hagita, Keita Naito, Mitsuhiro Karishuku, Masaya Kato, Satoshi Tanimura
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Publication number: 20210341149Abstract: Provided is a gas turbine combustor that can achieve improvement of the combustion stability. A gas turbine combustor includes a pilot burner of the diffusion combustion type, a pilot flow control valve that regulates a flow rate of fuel to be supplied to the pilot burner, a main burner of the premix combustion type arranged on an outer circumference side of the pilot burner, main flow control valves that regulate flow rates of fuel to be individually supplied to burner sectors into which the main burner is sectioned in a circumferential direction, and a controller configured to control the pilot flow control valve and the main flow control valves. The controller controls the main flow control valves such that, when fuel is to be supplied to all the burner sectors, a difference in fuel flow rate occurs between at least one burner sector and the other burner sectors among the burner sectors.Type: ApplicationFiled: April 29, 2021Publication date: November 4, 2021Inventors: Yasuhiro WADA, Kazuki ABE, Akinori HAYASHI, Keita NAITO
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Patent number: 10794296Abstract: The gas turbine combustor and the operation method thereof are designed to minimize visualization of exhaust gas from the gas turbine upon switching of the gas turbine fuel from the oil fuel to the gas fuel. Upon switching of the combustion by the pilot burner from the oil burning to the gas burning, the gas fuel is supplied to the main burners so as to start the gas burning. Then the gas fuel is supplied to the pilot burner to start the gas burning.Type: GrantFiled: October 23, 2017Date of Patent: October 6, 2020Assignee: Mitsubishi Hitachi Power Systems, Ltd.Inventors: Yasuhiro Akiyama, Mitsuhiro Karishuku, Keita Naito, Kanetsugu Nakamura, Satoshi Dodo, Tomohiro Asai, Yoshitaka Hirata, Akinori Hayashi
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Publication number: 20180112604Abstract: The gas turbine combustor and the operation method thereof are designed to minimize visualization of exhaust gas from the gas turbine upon switching of the gas turbine fuel from the oil fuel to the gas fuel. Upon switching of the combustion by the pilot burner from the oil burning to the gas burning, the gas fuel is supplied to the main burners so as to start the gas burning. Then the gas fuel is supplied to the pilot burner to start the gas burning.Type: ApplicationFiled: October 23, 2017Publication date: April 26, 2018Inventors: Yasuhiro AKIYAMA, Mitsuhiro KARISHUKU, Keita NAITO, Kanetsugu NAKAMURA, Satoshi DODO, Tomohiro ASAI, Yoshitaka HIRATA, Akinori HAYASHI
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Patent number: 9523620Abstract: It is an object of the present invention to provide a metal diaphragm capable of achieving a higher strength, excellent corrosion resistance, and a smooth surface condition, and a pressure sensor including the diaphragm. The diaphragm according to the present invention includes a two-phase stainless steel having a composition of 24 to 26 mass % Cr, 2.5 to 3.5 mass % Mo, 5.5 to 7.5 mass % Ni, 0.03 mass % or less C, 0.08 to 0.3 mass % N, and the balance Fe and inevitable impurities, and having a 0.2% proof stress of 1300 MPa or higher.Type: GrantFiled: January 23, 2014Date of Patent: December 20, 2016Assignee: SEIKO INSTRUMENTS INC.Inventors: Takuma Otomo, Keita Naito, Ryo Sugawara, Tomoo Kobayashi
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Patent number: 9393524Abstract: An engine exhaust treatment device is capable of combusting PM accumulated in a DPF or activating an exhaust purification catalyst even immediately after engine startup or at the time of light load operation. A combustible gas supply passage (8) communicates with an exhaust passage (4) on an upstream of a combustion catalyst (5). An air supply unit (9) and an ignition unit (10) are provided in this supply passage and interlocked with a control unit (11). Where a temperature of the exhaust is lower than a predetermined temperature, the control unit supplies air (12) to a combustible gas by the air supply unit (9) and causes ignition of the combustible gas by the ignition unit (10), so as to cause flame combustion of the combustible gas. The temperature of the exhaust (6) in the exhaust passage (4) is increased by heat of this flame combustion.Type: GrantFiled: January 26, 2012Date of Patent: July 19, 2016Assignee: KUBOTA CorporationInventors: Keita Naito, Toshio Nakahira, Yoshikazu Takemoto, Takashi Onishi
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Patent number: 9353666Abstract: An exhaust treatment device of a diesel engine is provided in which combustible gas is burned with oxygen in exhaust, combustion heat increases a temperature of the exhaust, and heat of the exhaust can burn and remove PM accumulating in a DPF. In order to cause a heater for radiating heat at a start of generation of the combustible gas to enter a catalyst inlet portion, and fit a liquid fuel retaining member over a periphery of the heater, a guide plate is provided to a lower face of the liquid fuel retaining member so that the air-fuel mixture moving down in the liquid fuel retaining member flows along an upper face of the guide plate out to a periphery of the guide plate.Type: GrantFiled: September 3, 2013Date of Patent: May 31, 2016Assignee: KUBOTA CorporationInventors: Takashi Onishi, Hidetaka Morinaga, Yoshikazu Takemoto, Toshio Nakahira, Mitsugu Okuda, Keita Naito
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Patent number: 9027933Abstract: An engine in which an oil consumption and a leakage of blow-by gas can be stably reduced for a long period of time. The engine includes a first land (3), a first ring groove (4), a second land (5), a second ring groove (6), a third land (7), a third ring groove (8), and a piston skirt (9) formed on a piston peripheral wall (1) in the above-recited order from a side of a piston head (2). A first pressure ring (10) is fitted in the first ring groove (4). A second pressure ring (11) is fitted in the second ring groove (6), an oil ring (12) fitted in the third ring groove (8), and an indentation (13) is formed at the second land (5).Type: GrantFiled: February 6, 2013Date of Patent: May 12, 2015Assignee: KUBOTA CorporationInventors: Hiroki Kuwayama, Takahiro Yamazaki, Yutaka Ishigaki, Hideyuki Koyama, Manabu Miyazaki, Yoshinori Tanaka, Keita Naito, Hidetaka Morinaga
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Publication number: 20140209220Abstract: It is an object of the present invention to provide a metal diaphragm capable of achieving a higher strength, excellent corrosion resistance, and a smooth surface condition, and a pressure sensor including the diaphragm. The diaphragm according to the present invention includes a two-phase stainless steel having a composition of 24 to 26 mass % Cr, 2.5 to 3.5 mass % Mo, 5.5 to 7.5 mass % Ni, 0.03 mass % or less C, 0.08 to 0.3 mass % N, and the balance Fe and inevitable impurities, and having a 0.2% proof stress of 1300 MPa or higher.Type: ApplicationFiled: January 23, 2014Publication date: July 31, 2014Applicant: Seiko Instruments Inc.Inventors: Takuma OTOMO, Keita NAITO, Ryo SUGAWARA, Tomoo KOBAYASHI
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Patent number: 8763374Abstract: An exhaust gas treatment device for a diesel engine capable of starting the generation of a combustible gas is provided. The device includes a combustible gas generator. A core member is fitted in the center portion of an annular wall to form an air-fuel mixing chamber between the inner peripheral surface of the annular wall and the outer peripheral surface of the core member. An air-fuel mixture gas in the air-fuel mixing chamber is adapted to be supplied from the end of the air-fuel mixing chamber to a combustible gas generating catalyst to a portion near the center thereof. A heater is used as the core member. The heat dissipating outer peripheral surface of the heater is exposed to the air-fuel mixing chamber. Heat is dissipated directly from the heat dissipating outer peripheral surface of the heater to the air-fuel mixing chamber when starting the generation of the combustible gas.Type: GrantFiled: March 16, 2011Date of Patent: July 1, 2014Assignee: KUBOTA CorporationInventors: Takashi Onishi, Keita Naito, Toshio Nakahira, Yoshikazu Takemoto
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Publication number: 20140072478Abstract: An exhaust treatment device of a diesel engine is provided in which combustible gas is burned with oxygen in exhaust, combustion heat increases a temperature of the exhaust, and heat of the exhaust can burn and remove PM accumulating in a DPF. In order to cause a heater for radiating heat at a start of generation of the combustible gas to enter a catalyst inlet portion, and fit a liquid fuel retaining member over a periphery of the heater, a guide plate is provided to a lower face of the liquid fuel retaining member so that the air-fuel mixture moving down in the liquid fuel retaining member flows along an upper face of the guide plate out to a periphery of the guide plate.Type: ApplicationFiled: September 3, 2013Publication date: March 13, 2014Applicant: KUBOTA CORPORATIONInventors: Takashi ONISHI, Hidetaka MORINAGA, Yoshikazu TAKEMOTO, Toshio NAKAHIRA, Mitsugu OKUDA, Keita NAITO
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Patent number: 8615992Abstract: A construction machine includes a negative parking brake whose braking state is released by a supply of hydraulic fluid. It also includes a parking brake hydraulic circuit that is branched from a hydraulic fluid supplying circuit, which supplies the hydraulic fluid to a transmission of the construction machine, and supplies the hydraulic fluid to the parking brake. The parking brake hydraulic circuit includes a check valve that prevents backflow of the hydraulic fluid of the parking brake to the hydraulic fluid supplying circuit, and it includes an operation switching valve, which is provided closer to the parking brake than the check valve, for switching between an activation and a release of the parking brake. The parking brake hydraulic circuit also includes a relief valve, which is interposed between the check valve and the operation switching valve and which discharges the hydraulic fluid of the parking brake when the relief valve is opened.Type: GrantFiled: May 19, 2011Date of Patent: December 31, 2013Assignee: Komatsu Ltd.Inventors: Keita Naito, Shunji Oka, Osamu Takatori
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Publication number: 20130336843Abstract: An engine exhaust treatment device is capable of combusting PM accumulated in a DPF or activating an exhaust purification catalyst even immediately after engine startup or at the time of light load operation. A combustible gas supply passage (8) communicates with an exhaust passage (4) on an upstream of a combustion catalyst (5). An air supply unit (9) and an ignition unit (10) are provided in this supply passage and interlocked with a control unit (11). Where a temperature of the exhaust is lower than a predetermined temperature, the control unit supplies air (12) to a combustible gas by the air supply unit (9) and causes ignition of the combustible gas by the ignition unit (10), so as to cause flame combustion of the combustible gas. The temperature of the exhaust (6) in the exhaust passage (4) is increased by heat of this flame combustion.Type: ApplicationFiled: January 26, 2012Publication date: December 19, 2013Applicant: KUBOTA CORPORATIONInventors: Keita Naito, Toshio Nakahira, Yoshikazu Takemoto, Takashi Onishi
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Publication number: 20130004279Abstract: A construction machine includes a negative parking brake whose braking state is released by a supply of hydraulic fluid. It also includes a parking brake hydraulic circuit that is branched from a hydraulic fluid supplying circuit, which supplies the hydraulic fluid to a transmission of the construction machine, and supplies the hydraulic fluid to the parking brake. The parking brake hydraulic circuit includes a check valve that prevents backflow of the hydraulic fluid of the parking brake to the hydraulic fluid supplying circuit, and it includes an operation switching valve, which is provided closer to the parking brake than the check valve, for switching between an activation and a release of the parking brake. The parking brake hydraulic circuit also includes a relief valve, which is interposed between the check valve and the operation switching valve and which discharges the hydraulic fluid of the parking brake when the relief valve is opened.Type: ApplicationFiled: May 19, 2011Publication date: January 3, 2013Applicant: Komatsu Ltd.Inventors: Keita Naito, Shunji Oka, Osamu Takatori
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Publication number: 20120312000Abstract: An exhaust gas treatment device for a diesel engine capable of starting the generation of a combustible gas is provided. The device includes a combustible gas generator. A core member is fitted in the center portion of an annular wall to form an air-fuel mixing chamber between the inner peripheral surface of the annular wall and the outer peripheral surface of the core member. An air-fuel mixture gas in the air-fuel mixing chamber is adapted to be supplied from the end of the air-fuel mixing chamber to a combustible gas generating catalyst to a portion near the center thereof. A heater is used as the core member. The heat dissipating outer peripheral surface of the heater is exposed to the air-fuel mixing chamber. Heat is dissipated directly from the heat dissipating outer peripheral surface of the heater to the air-fuel mixing chamber when starting the generation of the combustible gas.Type: ApplicationFiled: March 16, 2011Publication date: December 13, 2012Applicant: KUBOTA CORPORATIONInventors: Takashi Onishi, Keita Naito, Toshio Nakahira, Yoshikazu Takemoto