Patents by Inventor Youichi Ohshita

Youichi Ohshita 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: 7339132
    Abstract: A puffer type gas circuit breaker has a piston, which is connected with a center shaft via a link mechanism. At an initial stage of an interruption operation, the link mechanism drives a puffer cylinder and the piston both in an interruption direction while maintaining an almost constant distance therebetween. Even when a pressure rise occurs in a compression chamber by the heat of an arc generated in accordance with opening between a fixed arc contact and a movable arc contact, the pressure rise does not become an operation counterforce to an operator. At a final stage of the interruption operation where the fixed arc contact is removed from a throat of an insulating nozzle, the link mechanism drives the piston in an almost stopped status.
    Type: Grant
    Filed: December 6, 2005
    Date of Patent: March 4, 2008
    Assignee: Japan AE Power Systems Corporation
    Inventors: Hajime Urai, Youichi Ohshita, Makoto Koizumi, Naoki Osawa, Hiroaki Hashimoto, Junzo Kida
  • Publication number: 20060151438
    Abstract: A puffer type gas circuit breaker has a piston, which is connected with a center shaft via a link mechanism. At an initial stage of an interruption operation, the link mechanism drives a puffer cylinder and the piston both in an interruption direction while maintaining an almost constant distance therebetween. Even when a pressure rise occurs in a compression chamber by the heat of an arc generated in accordance with opening between a fixed arc contact and a movable arc contact, the pressure rise does not become an operation counterforce to an operator. At a final stage of the interruption operation where the fixed arc contact is removed from a throat of an insulating nozzle, the link mechanism drives the piston in an almost stopped status.
    Type: Application
    Filed: December 6, 2005
    Publication date: July 13, 2006
    Inventors: Hajime Urai, Youichi Ohshita, Makoto Koizumi, Naoki Osawa, Hiroaki Hashimoto, Junzo Kida
  • Publication number: 20040199478
    Abstract: To realize the multinational energy and power interchange, understanding the characteristics and differences of energy and power system of respective countries, electric power facilities of respective countries must be totally operated thus providing economic effects such as lowering of energy charge and the stable power supply. To this end, the respective power systems of many countries and regions such as North America, Russia, China, South East Asia, Australia, South America and the like belonging to the Asian-Pacific rim which have characteristics and difference are connected by direct current interconnecting facilities or alternating power transmission facilities thus ensuring the balance of power supply and enabling the total or partial operation of the entire system.
    Type: Application
    Filed: April 26, 2004
    Publication date: October 7, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Hiroshi Arita, Masahiro Watanabe, Junichi Makino, Tadashi Senda, Youichi Ohshita, Genichiro Ichihari, Naoyuki Yamada, Tetsuo Horiuchi, Chihiro Fukui, Hiroyuki Kudo
  • Publication number: 20020128749
    Abstract: To realize the multinational energy and power interchange, understanding the characteristics and differences of energy and power system of respective countries, electric power facilities of respective countries must be totally operated thus providing economic effects such as lowering of energy charge and the stable power supply. To this end, the respective power systems of many countries and regions such as North America, Russia, China, South East Asia, Australia, South America and the like belonging to the Asian-Pacific rim which have characteristics and difference are connected by direct current interconnecting facilities or alternating power transmission facilities thus ensuring the balance of power supply and enabling the total or partial operation of the entire system.
    Type: Application
    Filed: April 24, 2001
    Publication date: September 12, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Hiroshi Arita, Masahiro Watanabe, Junichi Makino, Tadashi Senda, Youichi Ohshita, Genichiro Ichihari, Naoyuki Yamada, Tetsuo Horiuchi, Chihiro Fukui, Hiroyuki Kudo
  • Publication number: 20020060497
    Abstract: To realize the multinational energy and power interchange, understanding the characteristics and differences of energy and power system of respective countries, electric power facilities of respective countries must be totally operated thus providing economic effects such as lowering of energy charge and the stable power supply. To this end, the respective power systems of many countries and regions such as North America, Russia, China, South East Asia, Australia, South America and the like belonging to the Asian-Pacific rim which have characteristics and difference are connected by direct current interconnecting facilities or alternating power transmission facilities thus ensuring the balance of power supply and enabling the total or partial operation of the entire system.
    Type: Application
    Filed: April 13, 1999
    Publication date: May 23, 2002
    Inventors: HIROSHI ARITA, MASAHIRO WATANABE, JUNICHI MAKINO, TADASHI SENDA, YOUICHI OHSHITA, GENICHIRO ICHIHARI, NAOYUKI YAMADA, TETSUO HORIUCHI, CHIHIRO FUKUI, HIROYUKI KUDO
  • Publication number: 20020024467
    Abstract: Electromagnetic waves induced by a partial discharge which occurs at the time of internal abnormality of a gas insulated apparatus are detected by a compact antenna having a high detection sensitivity for a board frequency band.
    Type: Application
    Filed: October 29, 2001
    Publication date: February 28, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Tatsuro Kato, Youichi Ohshita
  • Patent number: 6333715
    Abstract: With a circular signal receiving antenna unit (4) constituted by combining two pieces of semicircular conductive plates on a plane in a metallic vessel (3) for the gas insulated apparatus, the electromagnetic waves due to the partial discharge can be detected with a high sensitivity for a broad frequency band. The detected signals are measured by a measuring unit (10) via a hermetical seal coaxial terminal (7) and a coaxial cable (8). The antenna portions of the semicircular plates are designed to extend over a large area. Thus, a capacitance with a potential measurement portion can be increased and a potential measurement with high sensitivity can be performed.
    Type: Grant
    Filed: November 19, 1999
    Date of Patent: December 25, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Tatsuro Kato, Youichi Ohshita
  • Publication number: 20010005802
    Abstract: To realize the multinational energy and power interchange, understanding the characteristics and differences of energy and power system of respective countries, electric power facilities of respective countries must be totally operated thus providing economic effects such as lowering of energy charge and the stable power supply. To this end, the respective power systems of many countries and regions such as North America, Russia, China, South East Asia, Australia, South America and the like belonging to the Asian-Pacific rim which have characteristics and difference are connected by direct current interconnecting facilities or alternating power transmission facilities thus ensuring the balance of power supply and enabling the total or partial operation of the entire system.
    Type: Application
    Filed: December 21, 2000
    Publication date: June 28, 2001
    Inventors: Hiroshi Arita, Masahiro Watanabe, Junichi Makino, Tadashi Senda, Youichi Ohshita, Genichiro Ichihari, Naoyuki Yamada, Tetsuo Horiuchi, Chihiro Fukui, Hiroyuki Kudo
  • Patent number: 6005213
    Abstract: In an insulated type switchgear device in which a pair of arc electrodes are separably disposed in an opposing manner in a vacuum tube, and having a movable conductor extending from a back face of a movable one of the arc electrodes to the outside of the vacuum tube, the pair of arc electrodes are designed to be separated through a rotation of the movable conductor around a predetermined main axis.
    Type: Grant
    Filed: February 24, 1998
    Date of Patent: December 21, 1999
    Assignees: Hitachi, Ltd., The Tokyo Electric Power Co., Ltd.
    Inventors: Ayumu Morita, Takashi Sato, Youichi Ohshita, Tooru Tanimizu, Masayoshi Hayakawa, Toshio Horikoshi, Ryutaro Yamamoto
  • Patent number: 5952636
    Abstract: In a vacuum type switch gear device an L shaped stationary and movable conductors arrangement, a transitive portion from one spiral arc groove to a neighboring another spiral arc groove on the surface of a movable electrode defined by the terminating end portion of the one spiral groove, the starting end of the adjacent neighboring other spiral groove and the outer circumferential edge portion of the movable electrode is arranged in a substantially overlapping relationship in a vertical direction with the movable conductor. Thus an adverse effect of a current loop flowing through the movable conductor against an arc generated between movable and stationary electrodes is limited to thereby improve the circuit breaking performance.
    Type: Grant
    Filed: June 25, 1998
    Date of Patent: September 14, 1999
    Assignees: Hitachi, Ltd., The Tokyo Electric Power Co., Ltd.
    Inventors: Ayumu Morita, Takashi Sato, Youichi Ohshita, Tooru Tanimizu, Masayoshi Hayakawa, Toshio Horikoshi, Ryutaro Yamamoto
  • Patent number: 5850065
    Abstract: A dielectric gas produced at the time of current interruption is exhausted into an exhaust structure 1 through an opening 8 formed on a fixed-side support member 6 combined with a fixed arcing contact 4. The exhaust structure 1 has an enlarged portion with a gas flow cross section formed at least before a position at 1/2 of the overall length of the exhaust structure 1 that is uniformly enlarged toward the rear of the exhaust structure 1 with respect to the joint between the exhaust tube 1 and the fixed-side support member 6. As a result, the gas is immediately exhausted into the exhaust structure 1 and the interelectrode insulation recovery performance is ensured.
    Type: Grant
    Filed: January 15, 1997
    Date of Patent: December 15, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Noriyuki Yaginuma, Masanori Tsukushi, Makoto Yano, Katsuhiko Shiraishi, Youichi Ohshita
  • Patent number: 5837955
    Abstract: The gas circuit breaker comprises a metal container filled with an insulating gas; first and second contacts disposed opposite each other in the metal container so that they can be brought into and out of engagement with each other; and a metal shield arranged in the metal container to enclose the two contacts. A part or a whole of the surface of the shield is oxidized and covered with a fluororesin layer. The gas circuit breaker with this construction can protect the shield surface against flaking and scores when subjected to mechanical impacts and can maintain high dielectric strength without increasing the size of the circuit breaker.
    Type: Grant
    Filed: January 10, 1997
    Date of Patent: November 17, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Tomoaki Utsumi, Jun Nukaga, Youichi Ohshita, Goro Daimon, Kenji Tsuchiya, Hiroshi Yoshimoto
  • Patent number: 5777842
    Abstract: A transformer station includes a plurality of power transmission lines receiving electric power, a bus bar connected to the power transmission lines, a transformer connected to the bus bar to transform voltage of the electric power supplied from the bus bar, and breakers between one of the power transmission lines and the bus bar and between the transformer and the bus bar. The breakers are aligned along an imaginary line extending substantially parallel to the bus bar.
    Type: Grant
    Filed: April 24, 1996
    Date of Patent: July 7, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Masanori Tsukushi, Youichi Ohshita, Ken'ichi Natsui, Yuzuru Kamata, Makoto Yano, Noriyuki Yaginuma, Katsuhiko Shiraishi
  • Patent number: 5543597
    Abstract: A first puffer chamber is formed by a puffer cylinder having a substantially cylindrical flange portion and a shaft portion, and a fixedly disposed piston. The piston is formed in a cylindrical shape sealed with respect to an external space, and is constituted to be accommodated in the flange portion of the puffer cylinder at the circuit breaking position of the circuit breaking unit. The internal space of the piston is constituted as a second puffer chamber which is designed to communicate with the first puffer chamber. The gas accumulated in the second puffer chamber is continuously blown out toward between the electrodes, thereby prolonging an effective interruptable arc time span without increasing the size of the circuit interrupting unit and operating unit.
    Type: Grant
    Filed: April 12, 1994
    Date of Patent: August 6, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Atsuji Watanabe, Youichi Ohshita, Masatomo Ohno, Masanori Tsukushi, Shunji Tokuyama
  • Patent number: 5502290
    Abstract: A switching mechanism for use e.g. in a circuit breaker of an underground electric substation has a movable rod which causes opening and closing of an electrical contact and a hydraulic operating system. The hydraulic operating system uses a hydraulic fluid which has a high flammability temperature or is incombustible. Thus, even if such fluid leaks from the hydraulic operating system, the risk of fire or explosion is minimized. The hydraulic operating system may have a sealed tank for the fluid, preferably with a variable volume expansion chamber. In a further development, the hydraulic operating system and possibly parts of the movable rod, is enclosed in a casing which is sealed and is filled with a gas which does not support combustion therein. Thus, the risk of fire or explosion is further reduced. The casing may have a variable volume expansion chamber.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: March 26, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Osamu Koyanagi, Kunio Hirasawa, Masanori Tsukushi, Yukio Kurosawa, Tadashi Sato, Youichi Ohshita
  • Patent number: 5473494
    Abstract: An electrical power supply system includes an electrical power source system connected to a bus bar and a plurality of electric power transmission systems each connected via circuit breakers to the bus bar. The supply system has overvoltage suppression equipments each installed between the transmission system and the ground. The overvoltage suppression equipment includes a switching device and an impedance connected to the switching device. The switching device in a sound transmission system is closed when the circuit breaker operates in other faulty transmission system, thereby an overvoltage being occurred on the sound system is effectively suppressed.
    Type: Grant
    Filed: September 10, 1992
    Date of Patent: December 5, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Kurosawa, Youichi Ohshita, Masaru Watanabe, Isao Nishida, Yoshihito Asai, Tokio Yamagiwa
  • Patent number: 5391930
    Abstract: A circuit breaker with a parallel resistor which fulfills with a simple structure incompatible requirements for a resistance circuit making contact with regard to maintenance of the dielectric strength and prearcing characteristic between electrodes. A resistance circuit making contact 2 and a resistance circuit breaking contact 3 are electrically connected in parallel, one end of the parallel circuit is connected to one end of a common resistor and the other end of the parallel circuit and the other end of the resistor are connected to the respective ends of a main contact 1. After the opening of the resistance circuit making contact 2 the resistance circuit breaking contact 3 is still closed.
    Type: Grant
    Filed: May 26, 1992
    Date of Patent: February 21, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Youichi Ohshita, Katuichi Kashimura, Akira Hashimoto, Osamu Koyanagi, Yukio Kurosawa, Isao Nishida
  • Patent number: 5214595
    Abstract: An abnormality diagnosing system and method for high voltage power apparatus wherein a plurality of detectors for detecting abnormalities of the high voltage power apparatus and providing outputs indicative thereof are disposed to detect predetermined phenomena indicative of at least an insulation abnormality, power supply abnormality, and foreign matter among abnormalities existing inside of the high voltage power apparatus. A monitoring arrangement responsive to the outputs of the detectors provides at least one of an output and display of the kind of abnormality detected.
    Type: Grant
    Filed: November 7, 1991
    Date of Patent: May 25, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Jun Ozawa, Fumihiro Endo, Youichi Ohshita, Izumi Yamada, Tokio Yamagiwa, Hiroshi Yamada, Mitsuo Sawairi, Hashime Nagai
  • Patent number: 5155312
    Abstract: An interrupter including a gas pressurizer for pressurizing a gas to flow toward a forward end of at least one contact of the interrupter, and a first orifice forming a first space with the forward end of the at least one contact for passing the gas pressurized by the gas pressurizer when a flow of electric current is interrupted. A second orifice forms a second space with the at least one contact for passing the gas which passed through the first orifice, with a chamber being formed between the first and second orifices. The chamber has an inner diameter greater than an inner diameter of the first and second orifices. At least one pressurized gas passage is provided through which a portion of the pressurized gas is supplied to the chamber without passing the first orifice so that the pressurized gas supplied to the chamber through the pressurized gas passage flows to the first space formed by the forward end of the at least one contact and the first orifice.
    Type: Grant
    Filed: March 12, 1991
    Date of Patent: October 13, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Akira Hashimoto, Youichi Ohshita, Kogi Ishikawa, Masanori Tsukushi, Yukio Kurosawa
  • Patent number: 5107447
    Abstract: An abnormality diagnosing system and method for high voltage power apparatus wherein a plurality of detectors for detecting abnormalities of the high voltage power apparatus and providing outputs indicative thereof are disposed to detect predetermined phenomena indicative of at least an insulation abnormality, power supply abnormality and foregin matter among abnormalities existing inside of the high voltage power apparatus. A monitoring arrangement responsive to the outputs of the detectors provides at least one of an output and display of the kind of abnormality detected.
    Type: Grant
    Filed: May 16, 1989
    Date of Patent: April 21, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Jun Ozawa, Fumihiro Endo, Youichi Ohshita, Izumi Yamada, Tokio Yamagiwa, Hiroshi Yamada, Mitsuo Sawairi, Hashime Nagai