Patents by Inventor Naoki Nakatsugawa

Naoki Nakatsugawa 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: 8189325
    Abstract: A switchgear case is partitioned into a high voltage bus bar chamber, which contains bus bars and cable heads, a high voltage device chamber containing circuit breakers and operation mechanisms and a low voltage control chamber containing a relay and measurement devices, etc. A rear wall of the case has a first suction port disposed at a lower part thereof, wherein the high voltage bus bar chamber, high voltage device chamber and the low voltage control chamber are communicated and air passing through the chambers is discharged from a first discharging port of the casing. The bus bars electrically connecting the high voltage devices in the high voltage device chamber and connecting bars connecting the adjoining bus bars and the cable heads are covered with solid insulators for solid-insulation.
    Type: Grant
    Filed: December 9, 2008
    Date of Patent: May 29, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Takuya Kurogi, Kenji Tsuchiya, Naoki Nakatsugawa, Takumi Ishikawa, Nobuyuki Yamada
  • Patent number: 8045322
    Abstract: A solid insulated bus switchgear including a cabinet having unit and bus rooms, first and second switching units, each having a circuit breaker, current transformer, zero-phase sequence current transformer, and instrument voltage transformer, main buses, a communication bus linked to the main buses, and connected to the first and the second switching units, and first and second leader buses, the first connected to the first switching unit, the second connected to the second switching unit. Each switching unit has a movable cart, the circuit breaker mounted on the cart, and a frame assembly. Two terminals are disposed on the back of the circuit breaker, one connected to a fixed electrode and the other connected to a movable electrode of the circuit breaker. The two terminals are connected to the communication bus and to the first or second leader bus through air bushings.
    Type: Grant
    Filed: July 1, 2009
    Date of Patent: October 25, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Takuya Kurogi, Kenji Tsuchiya, Takumi Ishikawa, Naoki Nakatsugawa
  • Patent number: 7983023
    Abstract: Earthing equipment for a switchgear is comprised of a movable carrying cart, a switch portion, a manipulating portion, and a voltage detecting device. The earthing equipment is provided with: an upper conductor connected to any one of the movable electrode and the stationary electrode; a lower conductor connected to the other of the movable electrode and the stationary electrode, an earthing wire connecting the lower conductor to a terminal used for earthing of the switchgear; and an adaptor conductor being selectively connected to either a disconnection portion at a bus bar side or a disconnection portion at a cable side of the switchgear and is permitted to be selectively replaced on either upper or lower face of the upper conductor.
    Type: Grant
    Filed: February 17, 2010
    Date of Patent: July 19, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Shoda, Takuya Kurogi, Kenji Tsuchiya, Takumi Ishikawa, Naoki Nakatsugawa
  • Publication number: 20100208416
    Abstract: Arthing equipment for a switchgear is comprised of a movable carrying cart, a switch portion, a manipulating portion, and a voltage detecting device. The earthing equipment is provided with: an upper conductor connected to any one of the movable electrode and the stationary electrode; a lower conductor connected to the other of the movable electrode and the stationary electrode, an earthing wire connecting the lower conductor to a terminal used for earthing of the switchgear; and an adaptor conductor being selectively connected to either a disconnection portion at a bus bar side or a disconnection portion at a cable side of the switchgear and is permitted to be selectively replaced on either upper or lower face of the upper conductor.
    Type: Application
    Filed: February 17, 2010
    Publication date: August 19, 2010
    Applicant: HITACHI, LTD.
    Inventors: Kenichi SHODA, Takuya KUROGI, Kenji TSUCHIYA, Takumi ISHIKAWA, Naoki NAKATSUGAWA
  • Publication number: 20100002363
    Abstract: A solid insulated bus switchgear, comprising: a cabinet having unit rooms defined by a ground metal plate on a front side thereof and a bus room defined by a ground metal plate on a rear side thereof; a first switching unit and a second switching unit, each of which has a circuit breaker, a current transformer, a zero-phase sequence current transformer, and an instrument voltage transformer, the first switching unit and the second switching unit being vertically stacked in the cabinet; main buses, which are solid-insulated, placed in the bus room in the cabinet in the width direction of the cabinet; a communication bus, which is solid-insulated, linked to the main buses, and connected to one end of the first switching unit at one end and to one end of the second switching unit at another end; and a first leader bus and a second leader bus, which are solid-insulated, the first leader bus being connected to another end of the first switching unit, the second leader bus being connected to another end of the seco
    Type: Application
    Filed: July 1, 2009
    Publication date: January 7, 2010
    Inventors: Takuya KUROGI, Kenji Tsuchiya, Takumi Ishikawa, Naoki Nakatsugawa
  • Publication number: 20090159569
    Abstract: A switchgear case is partitioned into a high voltage bus bar chamber, which contains bus bars and cable heads, a high voltage device chamber containing circuit breakers and operation mechanisms and a low voltage control chamber containing a relay and measurement devices, etc., A rear wall of the case has a first suction port disposed at a lower part thereof, wherein the high voltage bus bar chamber, high voltage device chamber and the low voltage control chamber are communicated and air passing through the chambers is discharged from a first discharging port of the casing. The bus bars electrically connecting the high voltage devices in the high voltage device chamber and connecting bars connecting the adjoining bus bars and the cable heads are covered with solid insulators for solid-insulation.
    Type: Application
    Filed: December 9, 2008
    Publication date: June 25, 2009
    Inventors: Takuya KUROGI, Kenji Tsuchiya, Naoki Nakatsugawa, Takumi Ishikawa, Nobuyuki Yamada
  • Patent number: 7320759
    Abstract: A sludge treatment method allowing an improvement in a phosphorus recovery rate and sludge volume reduction by efficiently eluting phosphorus in the sludge. The sludge treatment method includes: a step of foaming a sludge-containing liquid by blowing an ozone-containing gas into the sludge-containing liquid; and a step of eluting phosphorus in the sludge-containing liquid by bringing sludge adsorbed on bubbles and a sludge-dissolving agent into contact with each other. The sludge treatment method may further include the steps of: separating the phosphorus eluted sludge-containing liquid into a phosphorus eluate and a residual sludge; and precipitating a phosphorus compound by adding a coagulant to the separated phosphorus eluate.
    Type: Grant
    Filed: November 13, 2006
    Date of Patent: January 22, 2008
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Nozomu Yasunaga, Toshiyuki Kamiya, Naoki Nakatsugawa, Junji Hirotsuji
  • Patent number: 7288191
    Abstract: A sludge treatment method allowing an improvement in a phosphorus recovery rate and sludge volume reduction by efficiently eluting phosphorus in the sludge. The sludge treatment method includes: a step of foaming a sludge-containing liquid by blowing an ozone-containing gas into the sludge-containing liquid; and a step of eluting phosphorus in the sludge-containing liquid by bringing sludge adsorbed on bubbles and a sludge-dissolving agent into contact with each other. The sludge treatment method may further include the steps of: separating the phosphorus eluted sludge-containing liquid into a phosphorus eluate and a residual sludge; and precipitating a phosphorus compound by adding a coagulant to the separated phosphorus eluate.
    Type: Grant
    Filed: October 12, 2004
    Date of Patent: October 30, 2007
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Nozomu Yasunaga, Toshiyuki Kamiya, Naoki Nakatsugawa, Junji Hirotsuji
  • Publication number: 20070068876
    Abstract: A sludge treatment method allowing an improvement in a phosphorus recovery rate and sludge volume reduction by efficiently eluting phosphorus in the sludge. The sludge treatment method includes: a step of foaming a sludge-containing liquid by blowing an ozone-containing gas into the sludge-containing liquid; and a step of eluting phosphorus in the sludge-containing liquid by bringing sludge adsorbed on bubbles and a sludge-dissolving agent into contact with each other. The sludge treatment method may further include the steps of: separating the phosphorus eluted sludge-containing liquid into a phosphorus eluate and a residual sludge; and precipitating a phosphorus compound by adding a coagulant to the separated phosphorus eluate.
    Type: Application
    Filed: November 13, 2006
    Publication date: March 29, 2007
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Nozomu Yasunaga, Toshiyuki Kamiya, Naoki Nakatsugawa, Junji Hirotsuji
  • Publication number: 20050145575
    Abstract: A sludge treatment method allowing an improvement in a phosphorus recovery rate and sludge volume reduction by efficiently eluting phosphorus in the sludge. The sludge treatment method includes: a step of foaming a sludge-containing liquid by blowing an ozone-containing gas into the sludge-containing liquid; and a step of eluting phosphorus in the sludge-containing liquid by bringing sludge adsorbed on bubbles and a sludge-dissolving agent into contact with each other. The sludge treatment method may further include the steps of: separating the phosphorus eluted sludge-containing liquid into a phosphorus eluate and a residual sludge; and precipitating a phosphorus compound by adding a coagulant to the separated phosphorus eluate.
    Type: Application
    Filed: October 12, 2004
    Publication date: July 7, 2005
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Nozomu Yasunaga, Toshiyuki Kamiya, Naoki Nakatsugawa, Junji Hirotsuji
  • Patent number: 6884355
    Abstract: A process for treating organic wastewater which comprises treating organic wastewater with ozone and successively with alkali and introducing said alkali treated organic wastewater into an anaerobic digestion tank for anaerobic digestion. Instead of the ozone and successive alkali treatments, ozone treatment in the presence of hydrogen peroxide or ozone treatment under UV radiation is applicable. Prior to introduction into the anaerobic digestion tank, the treated wastewater may be separated into solids and phosphorus is preferably recovered from the solution. Solubilization of solids in the organic wastewater and transformation of organic substances into methane are greatly enhanced and sludge to be disposed is greatly reduced. Moreover, phosphorus is efficiently eluted out and recovered from solids in the organic wastewater.
    Type: Grant
    Filed: June 4, 2003
    Date of Patent: April 26, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Toshiyuki Kamiya, Junji Hirotsuji, Nozomu Yasunaga, Seiji Furukawa, Naoki Nakatsugawa
  • Publication number: 20030226803
    Abstract: A process for treating organic wastewater which comprises treating organic wastewater with ozone and successively with alkali and introducing said alkali treated organic wastewater into an anaerobic digestion tank for anaerobic digestion. Instead of the ozone and successive alkali treatments, ozone treatment in the presence of hydrogen peroxide or ozone treatment under UV radiation is applicable. Prior to introduction into the anaerobic digestion tank, the treated wastewater may be separated into solids and phosphorus is preferably recovered from the solution. Solubilization of solids in the organic wastewater and transformation of organic substances into methane are greatly enhanced and sludge to be disposed is greatly reduced. Moreover, phosphorus is efficiently eluted out and recovered from solids in the organic wastewater.
    Type: Application
    Filed: June 4, 2003
    Publication date: December 11, 2003
    Applicant: Mitsibishi Denki Kabushiki Kaisha
    Inventors: Toshiyuki Kamiya, Junji Hirotsuji, Nozomu Yasunaga, Seiji Furukawa, Naoki Nakatsugawa
  • Patent number: 6259051
    Abstract: There is disclosed a vacuum insulation switch provided with a movable electrode, a stationary electrode and an earthing electrode, which are insulated from each other, in a vacuum container made of a conductive material which is earthed, and a switchgear using the same. Since the vacuum insulation, which is excellent in the insulation ability, is utilized, the switch is drastically miniaturized and the number of constituent parts are reduced, whereby the manufacturing cost of the switch and the switchgear can be decreased.
    Type: Grant
    Filed: May 2, 2000
    Date of Patent: July 10, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Toru Tanimizu, Masato Kobayashi, Shuichi Kikukawa, Ayumu Morita, Minoru Suzuki, Yoshimi Hakamata, Katsunori Kojima, Yozo Shibata, Yoshitomo Gotoh, Makoto Terai, Takuya Okada, Naoki Nakatsugawa
  • Patent number: 6144005
    Abstract: A vacuum insulation switch provided with a movable electrode, a stationary electrode and an earthing electrode, which are insulated from each other, in a vacuum container made of a conductive material which is earthed, and a switchgear using the same.
    Type: Grant
    Filed: July 14, 1998
    Date of Patent: November 7, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Toru Tanimizu, Masato Kobayashi, Shuichi Kikukawa, Ayumu Morita, Minoru Suzuki, Yoshimi Hakamata, Katsunori Kojima, Yozo Shibata, Yoshitomo Gotoh, Makoto Terai, Takuya Okada, Naoki Nakatsugawa
  • Patent number: 5591349
    Abstract: An organism deposition preventing system for removing organisms propagated in water comprises: an ozonizer for generating ozone, an ozone adsorber containing an ozone adsorbent for storing ozone generated by the ozonizer, a water-jet ejector for injecting an ozonous gas produced by desorbing ozone from the ozone adsorbent of the ozone absorber into the water, and a carbon dioxide gas source means for supplying carbon dioxide gas to be injected into the water together with the ozonous gas or in synchronism with the injection of the ozonous gas into the water. A microorganism removing method for removing microorganisms propagated in water injects a mixed gas consisting of an ozonous gas and carbon dioxide gas into the water or injects carbon dioxide gas in synchronism with the injection of the ozonous gas into the water.
    Type: Grant
    Filed: November 14, 1994
    Date of Patent: January 7, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Akira Ikeda, Naoki Nakatsugawa, Yumiko Yoshimura, Yasuhiro Tanimura, Kenji Ezaki
  • Patent number: 5527459
    Abstract: A microbe propagation preventing apparatus is provided to prevent an ion from decreasing at a time of decomposing ozone generated by gaseous discharge or ionization so as to sufficiently generate air ion, and to sufficiently prevent propagation of microbes adhering to an object by using the air ion without secondary pollution. Further, in the apparatus, a gas containing the ion is supplied into water so as to prevent the microbe propagation in the water. In the apparatus, an ozone decomposing chamber is mounted to be electrically insulated from an air duct. An electrode to remove a positive ion is mounted to obtain only a negative ion, and extend a lifetime of the obtained ion. An ion supplying portion is mounted to supply an ionized gas into a space housing the object in which microbes can be propagated, and return the ionized gas to an ionization chamber. Further, a diffusing apparatus is provided to transform the ionic gas into bubbles so as to feed the bubbles into the water in the water reservoir.
    Type: Grant
    Filed: September 22, 1994
    Date of Patent: June 18, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Akira Ikeda, Yasuhiro Tanimura, Naoki Nakatsugawa, Masaaki Tanaka, Hiroshige Konishi, Toshie Hiraoka, Shinji Nishio, Hiroto Kawahira
  • Patent number: 5484570
    Abstract: A microbe propagation preventing apparatus and a microbe propagation preventing method are provided to prevent anion from decreasing at a time of decomposing ozone generated by gaseous discharge or ionization so as to sufficiently generate air ion, and to sufficiently prevent propagation of microbes adhering to an object by using the air ion without secondary pollution. Further, in the apparatus and the method, a gas containing the ion is supplied into water so as to prevent the microbe propagation in the water. In the apparatus, an ozone decomposing chamber is mounted to be electrically insulated from an air duct. An electrode to remove a positive ion is mounted to obtain only a negative ion, and extend a lifetime of the obtained ion. An ion supplying portion is mounted to supply an ionized gas into a space housing the object in which microbes can be propagated, and return the ionized gas to an ionization chamber.
    Type: Grant
    Filed: September 22, 1994
    Date of Patent: January 16, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Akira Ikeda, Yasuhiro Tanimura, Naoki Nakatsugawa, Masaaki Tanaka, Hiroshige Konishi, Toshie Hiraoka, Shinji Nishio, Hiroto Kawahira
  • Patent number: 5445798
    Abstract: A microbe propagation preventing apparatus and a microbe propagation preventing method are provided to prevent an ion from decreasing at a time of decomposing ozone generated by gaseous discharge or ionization so as to sufficiently generate air ion, and to sufficiently prevent propagation of microbes adhering to an object by using the air ion without secondary pollution. Further, in the apparatus and the method, a gas containing the ion is supplied into water so as to prevent the microbe propagation in the water. In the apparatus, an ozone decomposing chamber is mounted to be electrically insulated from an air duct. An electrode to remove a positive ion is mounted to obtain only a negative ion, and extend a lifetime of the obtained ion. An ion supplying portion is mounted to supply an ionized gas into a space housing the object in which microbes can be propagated, and return the ionized gas to an ionization chamber.
    Type: Grant
    Filed: November 22, 1993
    Date of Patent: August 29, 1995
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Akira Ikeda, Yasuhiro Tanimura, Naoki Nakatsugawa, Masaaki Tanaka, Hiroshige Konishi, Toshie Hiraoka, Shinji Nishio, Hiroto Kawahira
  • Patent number: 5350684
    Abstract: Methanohalococcus alcaliphilum having an optimum growth sodium chloride concentration ranging from about 2.5 to about 3 mole are herein disclosed. The bacteria are halophilic or halophilic and alkalophilic and can be used as the microorganisms which play a central role in the methods of methane fermentation to enhance the efficiency of such a method since the use of the microorganism makes it possible to carry out the method at an alkaline pH, in the presence of salts in a high concentration and at a low temperature.
    Type: Grant
    Filed: March 12, 1991
    Date of Patent: September 27, 1994
    Assignees: Research Development Corporation of Japan, Mitsubishi Electric Corporation, Rikagaku Kenkysuho
    Inventors: Naoki Nakatsugawa, Koki Horikoshi
  • Patent number: 5143835
    Abstract: Methanosarcina alcaliphilum which is alkalophilic methanogen having the optimum growth pH range of from about 8.1 to about 8.7. This strain exhibits excellent properties such as alkalophilicity and resistance to low temperature. This strain makes it possible to carry out methane fermentation methods at an alkaline pH and at a low temperature conditions. This strain is applied to methane fermentation in treating solid waste and waste water. Moreover, the bacterial concentration thereof in a reactor can be increased within a very short time and, therefore, the size of such a reactor can be made compact.
    Type: Grant
    Filed: March 6, 1989
    Date of Patent: September 1, 1992
    Assignees: Research Development Corporation of Japan, Naoki Nakatsugawa, Koki Horikoshi
    Inventors: Naoki Nakatsugawa, Koki Horikoshi