Patents by Inventor Kenji Yamaga
Kenji Yamaga 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: 10702944Abstract: An alloy structure has an arbitrary shape dimension which has high uniformity in the distribution of the element composition. The alloy structure contains Fe and at least four elements, which are selected from the group consisting of elements from atomic number 13 to atomic number 79 included in Group 3 to Group 16 of the periodic table of the elements and have a ratio of the atomic radius to an Fe atom of 0.83 or more but 1.17 or less, each of Fe and the four elements is contained in an atomic concentration range of 5 at % or more but 30 at % or less, a difference in atomic concentration between at least four elements among the at least four elements and Fe is in a range of less than 3 at %, and the alloy structure has, a column crystal in which the at least four elements and Fe are solid-dissolved.Type: GrantFiled: July 17, 2015Date of Patent: July 7, 2020Assignee: HITACHI METALS, LTD.Inventors: Takahiko Kato, Kousuke Kuwabara, Tadashi Fujieda, Kinya Aota, Isamu Takahashi, Hiroyuki Satake, Kenji Yamaga, Hajime Murakami
-
Patent number: 10576538Abstract: An alloy structure which has high uniformity in the distribution of the element composition and the mechanical strength and excellent high-temperature strength and corrosion resistance, contains Fe and at least four elements, which are selected from the group consisting of elements from atomic number 13 to atomic number 79, included in Group 3 to Group 16 of the periodic table of the elements, and have a ratio of the atomic radius to an Fe atom of 0.83 or more but 1.17 or less, each of the elements in an atomic concentration range of 5 at % or more but 30 at % or less, a difference in atomic concentration among the at least four elements and Fe is in a range of less than 3 at %, and the alloy structure has, as a main crystal, a column crystal in which the at least four elements and Fe are solid-dissolved.Type: GrantFiled: July 17, 2015Date of Patent: March 3, 2020Assignee: HITACHI METALS, LTD.Inventors: Takahiko Kato, Kousuke Kuwabara, Tadashi Fujieda, Kinya Aota, Isamu Takahashi, Kenji Yamaga, Hiroyuki Satake, Hajime Murakami
-
Publication number: 20170209954Abstract: An alloy structure has an arbitrary shape dimension which has high uniformity in the distribution of the element composition. The alloy structure contains Fe and at least four elements, which are selected from the group consisting of elements from atomic number 13 to atomic number 79 included in Group 3 to Group 16 of the periodic table of the elements and have a ratio of the atomic radius to an Fe atom of 0.83 or more but 1.17 or less, each of Fe and the four elements is contained in an atomic concentration range of 5 at % or more but 30 at % or less, a difference in atomic concentration between at least four elements among the at least four elements and Fe is in a range of less than 3 at %, and the alloy structure has, a column crystal in which the at least four elements and Fe are solid-dissolved.Type: ApplicationFiled: July 17, 2015Publication date: July 27, 2017Applicant: HITACHI, LTD.Inventors: Takahiko KATO, Kousuke KUWABARA, Tadashi FUJIEDA, Kinya AOTA, Isamu TAKAHASHI, Hiroyuki SATAKE, Kenji YAMAGA, Hajime MURAKAMI
-
Publication number: 20170209922Abstract: An alloy structure which has high uniformity in the distribution of the element composition and the mechanical strength and excellent high-temperature strength and corrosion resistance, contains Fe and at least four elements, which are selected from the group consisting of elements from atomic number 13 to atomic number 79, included in Group 3 to Group 16 of the periodic table of the elements, and have a ratio of the atomic radius to an Fe atom of 0.83 or more but 1.17 or less, each of the elements in an atomic concentration range of 5 at % or more but 30 at % or less, a difference in atomic concentration among the at least four elements and Fe is in a range of less than 3 at %, and the alloy structure has, as a main crystal, a column crystal in which the at least four elements and Fe are solid-dissolved.Type: ApplicationFiled: July 17, 2015Publication date: July 27, 2017Applicant: HITACHI, LTD.Inventors: Takahiko KATO, Kousuke KUWABARA, Tadashi FUJIEDA, Kinya AOTA, Isamu TAKAHASHI, Kenji YAMAGA, Hiroyuki SATAKE, Hajime MURAKAMI
-
Patent number: 8647784Abstract: A fuel cell stack start method is to provide in which without relying on oxidation and reduction condition of an anode, an output reduction of the fuel cell stack can be avoided. In the start method of a solid polymer type fuel cell stack that is comprised of a separator including an anode flow channel for flowing a fuel, another separator including a cathode flow channel for feeding an oxidant and electrodes and an electrolyte interposed between the separators, the method is characterized by performing successively a first step of feeding the fuel to the fuel cell stack under a condition that a cathode is covered by generated water, a second step of forming an oxide layer on the cathode, a third step of feeding the oxidant gas to the fuel cell stack and a fourth step of extracting load current from the fuel cell stack.Type: GrantFiled: November 18, 2009Date of Patent: February 11, 2014Assignee: Hitachi, Ltd.Inventors: Katsunori Nishimura, Kenji Yamaga, Osamu Kubota, Ko Takahashi
-
Publication number: 20130004869Abstract: A fuel cell system having a fuel cell 1, a load 8 connected to the output line of the fuel cell 1 and a control apparatus 20 for controlling an amount of current flowing to the load 8, wherein a stopping state for stopping the fuel cell system includes a first stage stopping state for stopping while remaining hydrogen in the hydrogen line and a second stage stopping state for stopping substituting the hydrogen line with air, and transfers to the second stage stopping state by way of the first stage stopping state.Type: ApplicationFiled: September 13, 2012Publication date: January 3, 2013Inventors: Kenji YAMAGA, Hironori Sasaki, Katsunori Nishimura
-
Patent number: 8257874Abstract: The fuel cell system includes a fuel cell stack, a fuel cell temperature sensor for measuring the internal temperature of the fuel cell, a voltage sensor for measuring the power generation voltage of the fuel cell, a current sensor for measuring the current flowing from the fuel cell, a radiator for radiating heat generated by the fuel cell, a fan attached to the radiator for controlling the heat radiation amount, a cooling water pump for increasing the pressure of a cooling fluid, a bypass valve for controlling the cooling fluid amount entering the radiator, and a controller, on the basis of the voltage information measured by the voltage sensor, the temperature information measured by the temperature sensor, and the current information measured by the current sensor, for controlling at least one of the operation amount of the cooling water pump, the operation amount of the fan, and the cooling fluid amount flowing through the bypass valve.Type: GrantFiled: October 25, 2010Date of Patent: September 4, 2012Assignee: Hitachi, Ltd.Inventors: Kenji Yamaga, Hironori Sasaki
-
Patent number: 8197987Abstract: A separator for fuel cell comprising an electrolyte with ionic conductivity, a pair of electrodes with the electrolyte sandwiched therebetween, and a separator 10 for individually supplying a fuel gas and an oxidizing agent gas to the pair of the electrodes, respectively, wherein the separator 10 is provided with a multilayered metal sheet with at least the outermost layer thereof, and a corrosion-resistant film covering the whole surface of the metal sheet in order to form a metal separator, and the metal separator is further provided with a reacting gas sealing unit 21, a reacting gas manifold junction unit 22, and a reacting gas rectification unit 23, formed of an elastic body.Type: GrantFiled: January 25, 2007Date of Patent: June 12, 2012Assignee: Hitachi, Ltd.Inventors: Hironori Sasaki, Kenji Yamaga, Katsunori Nishimura
-
Publication number: 20120107722Abstract: A separator for a fuel cell includes a metal separator (metal substrate) having projections formed by ribs, and porous members provided in a plurality of flow passages partitioned by the projections, in which a hydrophilic portion is provided in a center part of a cross section orthogonal to a flow direction in the porous member, and a water repellent portion is provided in at least a part of portions in contact with wall surfaces of the flow passage within a range of the cross section. According to the present invention, the mixed phase flow in which the reaction gas and the cooling water inside the flow passages are mixed can be made an even flow in the separator in which the porous members are provided in the gas flow passages.Type: ApplicationFiled: November 1, 2011Publication date: May 3, 2012Inventors: Hiroyuki SATAKE, Masaya KOZAKAI, Kenji YAMAGA
-
Patent number: 8137856Abstract: Excellent gas sealing properties were difficult to achieve with a structure that uses a meal material to control material cost and does not increase the number of components. A cell is configured by using a metal separator having at least one protruding structure between a manifold and an electrode channel, and having a communicating channel structure that forms a fluid circulating space by being folded back at the side containing a connection so that the tip of the protruding structure is in contact with a surface of the separator. Accordingly, a gas channel from the manifold to an electrode surface can be easily formed integrally. This can be applied to a metal material easily. Further, the present invention can provide excellent gas sealing properties.Type: GrantFiled: February 13, 2009Date of Patent: March 20, 2012Assignee: Hitachi, Ltd.Inventors: Kenji Yamaga, Tsutomu Okusawa, Masaya Kozakai
-
Patent number: 7952984Abstract: An optical recording medium and a method of recording and reproducing of the optical recording medium are provided, which are capable of recording and reproducing data with reliability even when blue or blue violet laser light is used as irradiation light. The optical recording medium has a recording layer in which a recording mark composed of a plurality of cavities is formed by irradiation of the laser light. The recording layer is configured so that, in a plan view taken in a direction of irradiation of the laser light, cavities lying in an area of the center and its vicinities of the recording mark, out of the plurality of cavities, include cavities greater than ones lying around the area.Type: GrantFiled: April 22, 2005Date of Patent: May 31, 2011Assignee: TDK CorporationInventors: Koji Mishima, Kenji Yamaga, Daisuke Yoshitoku
-
Patent number: 7932015Abstract: An optical recording medium includes a substrate and a plurality of recording layers laminated via at least intermediate layers, at least one of the recording layers other than a recording layer farthest from a light incidence plane among the plurality of recording layers containing at least one metal M selected from a group consisting of Ni, Cu, Si, Ti, Ge, Zr, Nb, Mo, In, Sn, W, Pb, Bi, Zn and La and an element X which can combine with the metal M upon being irradiated with a laser beam for recording data, thereby forming a crystal of a compound of the element X with the metal M. According to the thus constituted optical recording medium, it is possible to record data in and reproduce from a farthest recording layer from a light incidence plane in a desired manner and it is possible to record data in and reproduce from recording layer(s) other than the farthest recording layer from the light incidence plane in a desired manner.Type: GrantFiled: December 30, 2003Date of Patent: April 26, 2011Assignee: TDK CorporationInventors: Koji Mishima, Hiroyasu Inoue, Tsuyoshi Komaki, Daisuke Yoshitoku, Hitoshi Arai, Kenji Yamaga, Hironori Kakiuchi
-
Publication number: 20110065013Abstract: A fuel cell stack start method is to provide in which without relying on oxidation and reduction condition of an anode, an output reduction of the fuel cell stack can be avoided. In the start method of a solid polymer type fuel cell stack that is comprised of a separator including an anode flow channel for flowing a fuel, another separator including a cathode flow channel for feeding an oxidant and electrodes and an electrolyte interposed between the separators, the method is characterized by performing successively a first step of feeding the fuel to the fuel cell stack under a condition that a cathode is covered by generated water, a second step of forming an oxide layer on the cathode, a third step of feeding the oxidant gas to the fuel cell stack and a fourth step of extracting load current from the fuel cell stack.Type: ApplicationFiled: November 18, 2009Publication date: March 17, 2011Inventors: Katsunori Nishimura, Kenji Yamaga, Osamu Kubota, Ko Takahashi
-
Publication number: 20110039177Abstract: The fuel cell system includes a fuel cell stack, a fuel cell temperature sensor for measuring the internal temperature of the fuel cell, a voltage sensor for measuring the power generation voltage of the fuel cell, a current sensor for measuring the current flowing from the fuel cell, a radiator for radiating heat generated by the fuel cell, a fan attached to the radiator for controlling the heat radiation amount, a cooling water pump for increasing the pressure of a cooling fluid, a bypass valve for controlling the cooling fluid amount entering the radiator, and a controller, on the basis of the voltage information measured by the voltage sensor, the temperature information measured by the temperature sensor, and the current information measured by the current sensor, for controlling at least one of the operation amount of the cooling water pump, the operation amount of the fan, and the cooling fluid amount flowing through the bypass valve.Type: ApplicationFiled: October 25, 2010Publication date: February 17, 2011Inventors: Kenji YAMAGA, Hironori Sasaki
-
Publication number: 20100291448Abstract: There is provided a fuel cell system capable of minimizing the formation of a local cell even if the start and the stop are repeated, thereby substantially reducing a degradation in performance of the fuel cell. The fuel cell system includes a fuel cell; a hydrogen supply unit for supplying hydrogen to an anode channel of the fuel cell; an air-amount adjusting unit for adjusting the amount of air supplied to a cathode channel of the fuel cell and discharged from the cathode channel; an external load connected to the fuel cell; and a control unit for controlling an operation of the hydrogen supply unit, the air-amount adjusting unit, and the external load; in which the control unit controls the fuel cell system such that the cathode channel of the fuel cell is filled with air whose pressure is not higher than a saturated vapor pressure at the time of starting the fuel cell system, thereafter, the air is continuously led through the cathode channel of the fuel cell, and a load is drawn from the fuel cell.Type: ApplicationFiled: May 13, 2010Publication date: November 18, 2010Inventors: Kenji Yamaga, Katsunori Nishimura, Osamu Kubota
-
Publication number: 20100209803Abstract: Excellent gas sealing properties were difficult to achieve with a structure that uses a meal material to control material cost and does not increase the number of components. A cell is configured by using a metal separator having at least one protruding structure between a manifold and an electrode channel, and having a communicating channel structure that forms a fluid circulating space by being folded back at the side containing a connection so that the tip of the protruding structure is in contact with a surface of the separator. Accordingly, a gas channel from the manifold to an electrode surface can be easily formed integrally. This can be applied to a metal material easily. Further, the present invention can provide excellent gas sealing properties.Type: ApplicationFiled: February 13, 2009Publication date: August 19, 2010Inventors: Kenji YAMAGA, Tsutomu Okusawa, Masaya Kozakai
-
Patent number: 7745035Abstract: A separator for a fuel cell, comprising a planar panel formed therein with a plurality of manifolds for passing reactive fluid or cooling medium through adjacent cell, and a pair of conductive passage boards superposed with one another, interposing therebetween the planar panel, the passage boards being formed therein with a plurality of meandering through channels for distributing the reactive fluid or the cooling medium from the manifolds, wherein the planar panel being formed therein with slits through which channel defining walls of the meandering through channels of the fluid passages are electrically connected with each other.Type: GrantFiled: November 24, 2008Date of Patent: June 29, 2010Assignee: Hitachi, Ltd.Inventors: Hiroshi Yamauchi, Kenji Yamaga, Ko Takahashi
-
Patent number: 7745032Abstract: The fuel cell assembly disclosed includes at least one unit fuel cell comprising a separator having flow channels for oxidizing gas, a cathode to which the oxidizing gas is fed, a membrane electrolyte of proton conductivity, an anode to which fuel gas is fed, and a separator having flow channels for the fuel gas, the above members being arranged in order. The fuel cell assembly further comprises a humidifier having a porous member to humidify at least the fuel gas to be fed to the anode. The porous member of the humidifier is so disposed as to face at least the flow channels for the oxidizing gas so that water is supplied to the flow channels from part of the surface of the porous member opposite to the water supplying face and/or from the outer periphery of the porous member.Type: GrantFiled: October 16, 2003Date of Patent: June 29, 2010Assignee: Hitachi, Ltd.Inventors: Katsunori Nishimura, Jinichi Imahashi, Kenji Yamaga, Masahiro Komachiya, Makoto Morishima
-
Patent number: 7680018Abstract: An optical recording medium including a light transmitting layer having a uniform thickness formed on a substrate, in which a burr or stripping hardly occurs at the inner periphery of the light transmitting layer, and a manufacturing method and a manufacturing device of the optical recording medium are provided. An optical recording medium 10 is manufactured by a manufacturing method including: molding a disc-like shaped substrate 12 including an information recording face 12A on one side; forming a light transmitting layer 14 thinner than the substrate 12 on the information recording face 12A; forming a circular cut 16 in the light transmitting layer 14; and punching out an area inside the cut 16 by a punching tool 18 to form a center hole 14A in the light transmitting layer 14 and a center hole 20 in the substrate 12.Type: GrantFiled: June 6, 2003Date of Patent: March 16, 2010Assignee: TDK CorporationInventors: Tomoki Ushida, Mamoru Usami, Kenji Yamaga
-
Patent number: 7678486Abstract: A separator includes an electrically conductive flat plate and two electrically conductive channel plates superposed on each other with the electrically conductive flat plate interposed therebetween. The separator includes a plurality of manifolds for passing a reaction fluid to an adjacent cell are provided in the electrically conductive flat plate, and a plurality of zigzag or straight through-channels for permitting the flowing of the reaction fluid from the manifolds are formed in each of the two channel plates. The separator includes the through-channels in any one of the two electrically conductive channel plates disposed so that they are partially overlapped with the manifolds in the electrically conductive flat plate, and the through-channels in the other electrically conductive channel plate are formed to be partially larger than the contour of the electrically conductive flat plate.Type: GrantFiled: January 4, 2006Date of Patent: March 16, 2010Assignee: Hitachi, Ltd.Inventors: Hiroshi Yamauchi, Kenji Yamaga, Ko Takahashi