Patents by Inventor Toshiki Kahara

Toshiki Kahara 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: 7091625
    Abstract: During a time zone where a power demand is smaller than an average value of the entire power demands of homes, an excess portion obtained by subtracting a power demand from a base power portion supplied by PEFC (1) is charged in a capacitor (7) and a lead storage battery (8) in advance; and during a time zone where a power demand is larger than the average value, a peak power portion exceeding this average value is discharged from the capacitor (7) and the lead storage battery (8); thereby enabling the system to sufficiently meet daily home-use demand with requisite minimum equipment while effectively using surplus power. Thus, energy efficiency can be enhanced without wasting energy, and also cost efficiency can be improved.
    Type: Grant
    Filed: April 7, 2004
    Date of Patent: August 15, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Tsutomu Okusawa, Osamu Yokomizo, Toshiki Kahara, Kouichi Chino, Takaaki Mizukami, Shin Takahashi
  • Publication number: 20040212194
    Abstract: During a time zone where a power demand is smaller than an average value of the entire power demands of homes, an excess portion obtained by subtracting a power demand from a base power portion supplied by PEFC (1) is charged in a capacitor (7) and a lead storage battery (8) in advance; and during a time zone where a power demand is larger than the average value, a peak power portion exceeding this average value is discharged from the capacitor (7) and the lead storage battery (8); thereby enabling the system to sufficiently meet daily home-use demand with requisite minimum equipment while effectively using surplus power. Thus, energy efficiency can be enhanced without wasting energy, and also cost efficiency can be improved.
    Type: Application
    Filed: April 7, 2004
    Publication date: October 28, 2004
    Inventors: Tsutomu Okusawa, Osamu Yokomizo, Toshiki Kahara, Kouichi Chino, Takaaki Mizukami, Shin Takahashi
  • Patent number: 5676922
    Abstract: A faulty chemical reactor in a chemical plant is removed, heat exchange is conducted between the faulty chemical reactor and a new chemical reactor with which the faulty chemical reactor is to be replaced, and then the new chemical reactor is installed at the position from which the faulty chemical reactor was previously removed.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: October 14, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Shigeaki Namba, Shoji Takahashi, Toshiki Kahara, Nobuhiro Seiki
  • Patent number: 5563003
    Abstract: Molten carbonate type or phosphoric acid type fuel cells and a method for supplementing these fuel cells with an electrolyte are disclosed. A fuel cell having an extended life is provided by scattering a plurality of sealed supplementary electrolyte containers made of a material which is soluble in the electrolyte at elevated temperatures, and supplying the supplementary electrolyte from the dissolved containers to the fuel cell while the cell is working.
    Type: Grant
    Filed: March 18, 1994
    Date of Patent: October 8, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Hiroaki Suzuki, Keizou Ohtsuka, Toshiki Kahara, Tadashi Yoshida
  • Patent number: 5346777
    Abstract: There is disclosed a chemical reaction installation in which a number of chemical reaction vessels are arranged efficiently so as to decrease an installation area while keeping a good maintainability. A processing system is provided at the inside, and a multi-story construction is provided, and access for maintenance purposes can be obtained from the side of each floor of the multi-story construction.
    Type: Grant
    Filed: March 19, 1993
    Date of Patent: September 13, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Shigeaki Namba, Tatsuo Sakamoto, Toshiki Kahara
  • Patent number: 5213909
    Abstract: A fuel cell has a plurality of fuel cell sub-stacks each of which has cell bodies, at least one anode header and at least one cathode header and which are stacked to form a fuel cell stack body, and side thermal insulators which are provided on the side of the fuel cell stack body so as to keep the fuel cell sub-stacks warm and which are discrete from each other in the direction of stacking of the fuel cell sub-stacks, each of the plurality of side thermal insulators being independently supported.
    Type: Grant
    Filed: April 23, 1992
    Date of Patent: May 25, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Sei Takashima, Keizou Ohtsuka, Toshiki Kahara, Yasutaka Komatsu
  • Patent number: 5212022
    Abstract: The invention relates to internal-reforming fuel cells. They are each constructed of plural unit cells stacked one over another. Each unit cell is formed of a cathode, an electrolyte plate, an anode and a separator. Each unit cell also includes a generating zone formed by the cathode, anode and electrolyte plate; a reforming zone for reforming fuel gas; a fuel gas flow channel communicating with a fuel gas inlet and a fuel gas outlet and including a divided fuel gas flow channel for the unit cell; and an oxidant gas flow channel communicating with an oxidant gas inlet and an oxidant gas outlet and including a divided oxidant gas flow channel for the unit cell. The reforming zone is arranged in the fuel gas flow channel while the generating zone is arranged in contact with the fuel gas flow channel and the oxidant gas flow channel at a position downstream of the reforming zone while the fuel gas and oxidant gas are maintained separated from each other.
    Type: Grant
    Filed: September 20, 1990
    Date of Patent: May 18, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Tsutomu Takahashi, Keizou Ohtsuka, Toshiki Kahara, Yasutaka Komatsu
  • Patent number: 4902587
    Abstract: The present invention provides a fuel cell which is improved in creep resistance and sintering resistance of anode and in activity of anode and which can maintain high performance over a long time. This fuel cell comprises a laminate comprising an electrolyte holding material having pores for holding an electrolyte, an anode and a cathode which sandwich the electrolyte holding material and a separator provided with grooves for feeding a gas to the anode and cathode characterized in that the anode is a ternary anode which comprises nickel as a main component and additionally cobalt and chromium oxide.
    Type: Grant
    Filed: January 11, 1989
    Date of Patent: February 20, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Toshihiro Saitoh, Keizou Ohtsuka, Shuhei Yamaguchi, Toshiki Kahara
  • Patent number: 4810595
    Abstract: A molten carbonate fuel cell using molten carbonate as an electrolyte, carbonate ions as electric conductor, and feeding a hydrogen-enriched gas to the anode and a mixture of air and carbon dioxide gas to the cathode has its output fall by degrees with operation. It is surmised that one of the causes of this problem is ascribable to the fact that the molten carbonate electrolyte moves during operation to destroy equilibrium in the boundary between the electrolyte and electrodes. After studies for measures against the problem, the inventor found that the output of a fuel cell which has fallen can be improved by shutting off part or all of the raaction gases or reducing their feed for a while, and then restoring. The purpose of the present invention is to offer a high-performance stable-output molten carbonate fuel cell and its operation control method, incorporating the above findings in its operation control system.
    Type: Grant
    Filed: January 6, 1988
    Date of Patent: March 7, 1989
    Assignee: New Energy Development Organization
    Inventors: Toshiki Kahara, Masato Takeuchi, Hideo Okada, Kazuo Iwamoto, Yoshio Iwase, Kouichi Mitsugi
  • Patent number: 4643957
    Abstract: In a fuel cell comprising a pair of counterposed gas-diffusible electrodes, an electrolyte-retaining, porous matrix provided between and in contact with the electrodes, a fuel chamber for feeding a gaseous fuel to the anode of the pair of the electrodes and an oxidizing agent chamber for feeding a gaseous oxidizing agent to the cathode of the pair of the electrodes, the cell performance is remarkably prevented from lowering by making the electrolyte saturated absorption amount of the cathode smaller than that of the anode, thereby preventing migration of the electrolyte in the electrolyte-retaining matrix.
    Type: Grant
    Filed: April 11, 1985
    Date of Patent: February 17, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Seizi Takeuchi, Tomoichi Kamo, Tatsuo Horiba, Kunko Kitami, Toshikatsu Mori, Toshiki Kahara, Jinichi Imahashi, Akio Honji, Masato Takeuchi, Kohki Tamura
  • Patent number: 4623415
    Abstract: In a fuel cell comprising an electrolyte-retaining matrix interposed between a pair of gas-diffusion electrodes, the matrix comprises particles or fibers of a substance unreactive with phosphoric acid and having electron-insulating properties and an inorganic binder.
    Type: Grant
    Filed: January 18, 1985
    Date of Patent: November 18, 1986
    Assignees: Hitachi, Ltd., Hitachi Chemical Co., Ltd.
    Inventors: Toshiki Kahara, Shinpei Matsuda, Kenzo Ishii, Seizi Takeuchi, Jinichi Imahashi, Akio Honji
  • Patent number: 4555452
    Abstract: In operating a fuel cell comprising an oxidizing agent chamber subject to supply of an oxidizing agent gas and a fuel chamber subjected to supply of a fuel gas, sintering of noble metal particles such as platinum black as an electrode catalyst can be prevented from sintering by connecting the fuel cell to an outside auxiliary load circuit and controlling the unit cell voltage to not more than 0.80 V at start or discontinuation to operate the fuel cell or during the operation of the fuel cell when an outside load becomes too low due to fluctuation of the outside load. The fuel cell performance can be improved thereby.
    Type: Grant
    Filed: March 7, 1985
    Date of Patent: November 26, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Toshiki Kahara, Toshikatsu Mori, Jinichi Imahashi, Akio Honji, Kohki Tamura
  • Patent number: 4529671
    Abstract: In a fuel cell comprising an electrolyte-retaining matrix interposed between a pair of gas-diffusion electrodes, the matrix comprises particles or fibers of a substance unreactive with phosphoric acid and having electron-insulating properties and an inorganic binder.
    Type: Grant
    Filed: September 2, 1982
    Date of Patent: July 16, 1985
    Assignees: Hitachi, Ltd., Hitachi Chemical Co., Ltd.
    Inventors: Toshiki Kahara, Shinpei Matsuda, Kenzo Ishii, Seizi Takeuchi, Jinichi Imahashi, Akio Honji
  • Patent number: 4493879
    Abstract: A fuel cell comprising a pair of gas diffusion electrodes, an electrolyte retaining matrix disposed between said gas diffusion electrodes, and a phosphoric acid electrolyte disposed within said matrix, characterized by using as matrix that comprising one or more metal oxides having electronic insulation and insolubility in phosphoric acid and a binder is excellent in phosphoric acid retaining ability and can be used for a long period of time without degradation of the performance of fuel cell.
    Type: Grant
    Filed: March 11, 1982
    Date of Patent: January 15, 1985
    Assignees: Hitachi, Ltd., Hitachi Chemical Company, Ltd.
    Inventors: Toshiki Kahara, Shimpei Matsuda, Kenzo Ishii, Seizi Takeuchi, Jinichi Imahashi, Akio Honji
  • Patent number: 4446210
    Abstract: A fuel cell electrode being substantially free from cracks on the surface of catalyst layer on the electrode and having a good electrode performance under the atmospheric pressure or under pressure when assembled into a fuel cell, which comprises a gas-diffusing electroconductive substrate with continued pores and a water-repellent catalyst layer comprising electroconductive submicron particles having a catalyst, electroconductive materials each having a volume 10.sup.3 -10.sup.10 as large as the volume of the largest particle of the submicron particles and, if necessary, having a catalyst, and a water-repellent polymer as a binder, the electroconductive submicron particles and the electroconductive materials being provided in a mixing ratio by volume of the former to the latter of 95-50 to 5-50.
    Type: Grant
    Filed: April 8, 1982
    Date of Patent: May 1, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Hideo Okada, Jinichi Imahashi, Seizi Takeuchi, Sigeru Okabe, Toshiki Kahara, Kenzo Ishii, Masato Takeuchi, Shimpei Matsuda, Kohki Tamura, Hiroshi Tobita
  • Patent number: 4407905
    Abstract: Fuel cell with improved and stabilized electrode performance having at least one gas diffusion electrode, where the gas diffusion electrode comprises an electronconductive, gas-permeable substrate and an electrode catalyst uniformly distributed on the substrate, the electrode catalyst comprising colonies each consisting of not more than 20 primary particles of noble metal each having a size of 10-30 A and being uniformly distributed and deposited on carrier powder.
    Type: Grant
    Filed: October 14, 1981
    Date of Patent: October 4, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Seizi Takeuchi, Kenzo Ishii, Toshiki Kahara, Jinichi Imahashi, Masato Takeuchi, Hideo Okada, Sigeru Okabe, Shimpei Matsuda, Fumito Nakajima, Hirosi Tobita, Kohki Tamura
  • Patent number: 4324828
    Abstract: A positive plate composite agent consisting of a mixture of manganese dioxide, carbon powder and polytetrafluoroethylene powder is press-molded at a pressure in the range of 1 to 5 t/cm.sup.2. The resulting molded article is then pulvertized into massive particles having a particle size ranging from 0.03 to 15 mm.sup.3. The massive particles are then press-molded into a positive plate having a predetermined shape at a pressure in the range of 0.2 to 1 t/cm.sup.2.There is thus obtained a positive plate of an enclosed type battery which comprises a portion consisting of the compactly formed massive particles of the positive plate composite agent and a portion consisting of the coarsely formed small particles of the composite agent interposed between the massive particles so as to define paths or voids for the passage of an electrolyte.
    Type: Grant
    Filed: June 6, 1980
    Date of Patent: April 13, 1982
    Assignees: Hitachi, Ltd., Hitachi Chemical Co., Ltd.
    Inventors: Noboru Ebato, Toshiki Kahara, Kohki Tamura
  • Patent number: 4297231
    Abstract: Disclosed is a process for producing a positive electrode for a non-aqueous electrolytic cell. Manganese dioxide is heat-treated at a temperature between 250.degree. and 400.degree. C. The heat-treated manganese dioxide is next mixed with a conducting agent and binder. The binder is suspended in water by means of non-ionic surface active agent, and the mixture is heat-treated at a temperature between 180.degree. and 350.degree. C. and then pressured molded into a positive electrode. This production process allows the provision of a positive electrode for a non-aqueous electrolytic cell of excellent discharge characteristics.
    Type: Grant
    Filed: December 28, 1979
    Date of Patent: October 27, 1981
    Assignees: Hitachi, Ltd., Hitachi Chemical Co., Ltd.
    Inventors: Toshiki Kahara, Kohki Tamura, Noboru Ebata, Fumio Sato, Tomio Yoshida
  • Patent number: 4259415
    Abstract: A primary battery comprises a negative active material such as lithium, a positive active material and a non-aqueous electrolyte, wherein the positive active material further comprises a main positive active material such as manganese dioxide which takes main part in a primary discharge reaction together with the negative active material through the non-aqueous electrolyte and a precursor such as vanadium pentoxide or lead dioxide which takes part in the primary discharge reaction and produces a sub-positive active material, which takes part in a secondary discharge reaction.
    Type: Grant
    Filed: September 11, 1979
    Date of Patent: March 31, 1981
    Assignees: Hitachi, Ltd., Hitachi Chemical Co. Ltd.
    Inventors: Kohki Tamura, Toshiki Kahara, Tatsuo Horiba, Noboru Ebato, Osamu Asai
  • Patent number: 4197366
    Abstract: This invention relates to a non-aqueous electrolyte cell having an improved utilization of manganese dioxide. The utilization of manganese dioxide of a conventional non-aqueous electrolyte cell comprising a negative active material which comprises lithium, sodium or the like; a positive active material which comprises manganese dioxide; and a non-aqueous electrolyte can be greatly improved by limiting the particle sizes of manganese dioxide powder, carbon powder and optional binder powder contained in the positive mass to, respectively, up to 30 .mu.m, up to 5 .mu.m and up to 3 .mu.m.
    Type: Grant
    Filed: August 10, 1978
    Date of Patent: April 8, 1980
    Assignees: Hitachi, Ltd., Hitachi Chemical Co., Ltd.
    Inventors: Kohki Tamura, Toshiki Kahara, Tatuo Horiba, Noboru Ebato