Patents by Inventor Shigeru Azuhata

Shigeru Azuhata 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: 5186146
    Abstract: A combustion/evaluation apparatus having a sampling member for sampling light emitted from flame in an internal combustion engine, optical fibers for separating the light sampled by the sampling member into at least two lights, optical filters for selectively transmitting lights having different wavelengths by being provided in optical paths for the separated lights, photoelectric conversion elements for respectively converting optical signals transmitted through the optical filters into electrical signals, and a calculation/evaluation unit for calculating an air ratio and a temperature for evaluation of the combustion condition of the flame by using a ratio of outputs from the photoelectric conversion elements, and for evaluating the combustion condition on the basis of the air ratio and the temperature.
    Type: Grant
    Filed: April 6, 1992
    Date of Patent: February 16, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Sohma, Tugihiro Yukitake, Shigeru Azuhata, Norio Arashi, Hiroatsu Tokuda
  • Patent number: 5067419
    Abstract: A low-NOx boiler comprises a burner for burning gaseous fuel, heat transfer pipes heating water by combustion heat of the burner to generate steam and having a passage through which water flows, a steam drum communicating with the heat transfer pipe and accumulating the steam from the heat transfer pipe, and an exhaust gas duct located in the furnace to exhaust combustion gas generated by combustion of gaseous fuel outside of the boiler. The boiler further comprises unburnt gas burner in the exhaust gas duct for burning unburnt content in the combustion gas flowing in the duct. The unburnt gas burner includes a nozzle for injecting premixture flow of fuel and combustion air and flame holding plate located near the downstream side of the outlet of the nozzle to interrupt the premixture flow to form a circulating flow on downstream side of the flame holding plate. As gaseous fuel and air are mixed in advance and a flame is formed, the flame length can be shortened.
    Type: Grant
    Filed: December 26, 1989
    Date of Patent: November 26, 1991
    Assignees: Hitachi, Ltd., Hitachi Babcock Kabushiki-kaisha
    Inventors: Hironobu Kobayashi, Shigeru Azuhata, Kiyoshi Narato, Kenichi Sohma, Yasuo Yoshii, Norio Arashi, Shigekazu Nishimoto, Isao Koyama, Tooru Inata, Hideo Kikuchi, Tadayoshi Murakami, Masayuki Taniguchi, Hiroshi Miyadera, Fumio Koda, Tatsuzou Enomoto, Kenshi Kobayashi
  • Patent number: 5038558
    Abstract: A gas turbine combustor comprises a combustion chamber, a premixing chamber in which hydrocarbon fuel and air are premixed, a nozzle with swirler for swirling and injecting the premixed fuel and air into the combustion chamber, to effect premixed combustion, and a fuel nozzle projecting into the combustion chamber and adapted to inject fuel at region wherein the premixed combustion is completed, so as to effect low air-ratio diffusion combustion thereby to produce reducing substance. NOx produced by the premixed combustion is reduced by reducing reaction with the reducing substances, so that the NOx concentration in the combustion gas is reduced. The combustor further includes an after-air ports on a peripheral wall defining the combustion chamber to effect combustion of unburnt substances.
    Type: Grant
    Filed: December 30, 1988
    Date of Patent: August 13, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Sohma, Shigeru Azuhata, Yasuo Iwai, Tooru Inada, Hironobu Kobayashi, Kiyoshi Narato, Stephen M. Masutani, Tadayoshi Murakami, Norio Arashi, Yoji Ishibashi, Michio Kuroda
  • Patent number: 5022849
    Abstract: A low NOx burning method and apparatus wherein a low air ratio flame burned with an amount of air less than an amount of air in a theoretical air ratio required for burning fuel perfectly is formed, and combustibles discharged from the low air ratio flame are burned at a trailing stream of the low air ratio flame while supplying air. The low air ratio flame is a premixing flame burned by premixing the fuel and air, and combustion of the premixing flames is maintained in the vicinity of the premixing flame. In this way, the generation of the NOx during the burning can be greatly decreased, and the required apparatus can be small-sized.
    Type: Grant
    Filed: July 14, 1989
    Date of Patent: June 11, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Yasuo Yoshii, Shigeru Azuhata, Norio Arashi, Kenichi Sohma, Tooru Inada, Hideo Kikuchi, Masayuki Taniguchi, Kiyoshi Narato, Hironobu Kobayashi, Tadayoshi Murakami, Michio Kuroda, Yoji Ishibashi, Stephen M. Masutani
  • Patent number: 4973159
    Abstract: A spectroscope apparatus includes a device for separating light from an object to be measured into spectral components, a device for mixing spectral components which exists in a desired wavelength range, and a device for forming an image of the to-be-measured body of mixed light. The image obtained is very useful for observing the state of a combustion flame, the progress a photochemical reaction, the progress of a biochemical reaction, tissue in a cell, and the state of a flame for analyzing a solution which contains a metal ion by flame spectrophotometry. The apparatus provides accurate analytical information and makes possible precise control operations.
    Type: Grant
    Filed: December 23, 1988
    Date of Patent: November 27, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Sohma, Shigeru Azuhata, Kiyoshi Narato, Tooru Inada, Hironobu Kobayashi, Norio Arashi, Hiroshi Miyadera
  • Patent number: 4907962
    Abstract: A low NOx burner comprises a pulverized coal nozzle for injecting a flow of a mixture of pulverized coal with primary air, a secondary air nozzle arranged externally of and coaxially with the pulverized coal nozzle, a tertiary air nozzle arranged externally of the secondary air nozzle and disposed coaxially with the pulverized coal nozzle, and a swirl flow generator for injecting secondary air and tertiary air as a respective swirl flow. Between the secondary air nozzle and the tertiary air nozzle, there is provided a spacer having such a thickness as to delay the mixing of the secondary air and the tertiary air and to form a swirl flow between the secondary air and the tertiary air.
    Type: Grant
    Filed: May 26, 1987
    Date of Patent: March 13, 1990
    Assignees: Hitachi, Ltd., Babcock-Hitachi Kabushiki
    Inventors: Shigeru Azuhata, Kiyoshi Narato, Hironobu Kobayashi, Kenichi Sohma, Tooru Inada, Norio Arashi, Hiroshi Miyadera, Masao Masutani
  • Patent number: 4820046
    Abstract: A spectroscope apparatus includes means for separating light from an object to be measured into spectral components, means for mixing that part of the spectral components which exists in a desired wavelength range, and means for forming an image of the to-be-measured body of mixed light. The image thus obtained is very useful for observing the state of a combustion flame, the progress of photochemical reaction, the progress of biochemical reaction, a desired tissue in a cell, and the state of a flame for analyzing a solution which contains a metal ion, by flame spectrophotometery, that is, provides accurate information and makes possible a precise control operation.
    Type: Grant
    Filed: November 12, 1987
    Date of Patent: April 11, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Sohma, Shigeru Azuhata, Kiyoshi Narato, Tooru Inada, Hironobu Kobayashi, Norio Arashi, Hiroshi Miyadera
  • Patent number: 4784043
    Abstract: An atomizer including a fuel supply passage for supplying a fuel, an atomizing medium supply passage for supplying an atomizing medium which is to be mixed with the fuel, a mixing chamber in communication with the fuel supply passage and the atomizing medium supply passage, and spray ports for spraying the fluid mixture consisting of the fuel and the atomizing medium from the mixing chamber. The fuel supply passage and the atomizing medium supply passages are communicated with the mixing chamber through a pre-mixing chamber having an annular cross-section defined by a large-diameter cylindrical surface and a small-diameter cylindrical surface. The fuel and the atomizing medium supplied from the fuel supply passage and the atomizing medium supply passage are pre-mixed the pre-mixing chamber. With this arrangement, it is possible to efficiently mix a slurry fuel and an atomizing medium, thus reducing the particle size of the atomized fuel particles and shortening the flame length.
    Type: Grant
    Filed: May 6, 1987
    Date of Patent: November 15, 1988
    Assignees: Hitachi, Ltd., Babcock-Hitachi Kabushiki Kaisha
    Inventors: Hironobu Kobayashi, Shigeru Azuhata, Kiyoshi Narato, Tooru Inada, Kenichi Sohma, Norio Arashi, Hiroshi Miyadera, Yoshitaka Takahashi
  • Patent number: 4741279
    Abstract: A method of combusting a coal-water mixture fuel. The mixture is atomized into a conically-shaped primary pre-combustion chamber. Primary air is supplied, at a rate smaller than that required for complete burning of the mixture and in the form of a swirl about the axis of the jet of the atomized mixture, from the peripheral portion of the primary pre-combustion chamber into a secondary pre-combustion chamber connected to said primary pre-combustion chamber, thus forming a region of low pressure around the jet of the mixture. The region of low pressure serves to induce the atmosphere gas from the secondary pre-combustion chamber of higher temperature back into the primary pre-combustion chamber of a lower temperature, so that the water content of the mixture is evaporated and the mixture is ignited by the heat of the hot atmosphere gas.
    Type: Grant
    Filed: January 7, 1987
    Date of Patent: May 3, 1988
    Assignees: Hitachi, Ltd., Babcock-Hitachi Kabushiki Kaisha
    Inventors: Shigeru Azuhata, Kazutoshi Higashiyama, Kiyoshi Narato, Hironobu Kobayashi, Norio Arashi, Tooru Inada, Kenichi Sohma, Keizou Ohtsuka, Yoshitaka Takahashi, Fumio Koda, Tadahisa Masai, Masakiyo Tanikawa, Kei Kawano
  • Patent number: 4653998
    Abstract: A furnace system connected to a burner including a furnace for burning a fuel and air ejected from the burner into the furnace to produce a flame therein, and a combustion condition determining device for determining the conditions of combustion of the fuel in a zone of the flame extending along different strata thereof by collecting light in the flame at one point in the flame by moving such point. Signals outputted by the combustion condition determining device are utilized for monitoring or controlling the flame and controlling exhaust emission control devices for controlling exhaust emissions produced by the combustion of the fuel. Control of the conditions of combustion of the flame can be effected quickly with a high degree of precision by monitoring the flame.
    Type: Grant
    Filed: January 25, 1985
    Date of Patent: March 31, 1987
    Assignees: Hitachi, Ltd., Babcock-Hitachi Kabushiki Kaisha
    Inventors: Ken-ichi Sohma, Norio Arashi, Shigeru Azuhata, Kiyoshi Narato, Tooru Inada, Hironobu Kobayashi, Keizou Ohtsuka, Yukio Hishinuma
  • Patent number: 4515094
    Abstract: There are the primary fuel nozzle for jetting the first coal in the fine powder form with an air ratio up to 1, and the secondary fuel nozzle for jetting the second coal in the fine powder form with an air ratio at least 1 from the outer circumferential portion of the primary fuel nozzle. Swirl means are located at the top of the secondary fuel nozzle for swirling the second coal.
    Type: Grant
    Filed: December 12, 1983
    Date of Patent: May 7, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Shigeru Azuhata, Norio Arashi, Kiyoshi Narato, Tooru Inada, Kenichi Souma, Keizou Ohtsuka, Yukio Hishinuma, Tadahisa Masai
  • Patent number: 4213944
    Abstract: A hot gas containing nitrogen oxides is admixed with ammonia and hydrogen peroxide to reduce the nitrogen oxides to nitrogen and water. Reduction reaction of the nitrogen oxides by ammonia is considerably promoted in a temperature range of 400.degree. to 800.degree. C. by the addition of hydrogen peroxide, and also ammonia present in excess of the nitrogen oxides is decomposed thereby, eliminating an unreacted ammonia effluent.
    Type: Grant
    Filed: December 9, 1977
    Date of Patent: July 22, 1980
    Assignee: Hitachi, Ltd.
    Inventors: Shigeru Azuhata, Hidetoshi Akimoto, Hideo Kikuchi, Yukio Hishinuma, Ryoichiro Oshima, Yoshijiro Arikawa
  • Patent number: 4119702
    Abstract: Nitrogen oxides in a combustion flue gas are removed by reduction in a gaseous phase at a low temperature in the absence of any catalyst by adding urea and an oxidizing agent for decomposition of urea, such as ozone, nitric acid, hydrogen peroxide, chlorine, chlorine dioxide, or oxy acids of chlorine or their salts. NO.sub.x removal can be carried out in a very simplified manner with high percent NO.sub.x removal.
    Type: Grant
    Filed: July 21, 1977
    Date of Patent: October 10, 1978
    Assignee: Hitachi, Ltd.
    Inventors: Shigeru Azuhata, Hideo Kikuchi, Hidetoshi Akimoto, Yukio Hishinuma, Yoshijiro Arikawa