Patents by Inventor Kazuhide Bannai

Kazuhide Bannai 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).

  • Surge arrester and gas-insulated electric apparatus
    Patent number: 8705220
    Abstract: A surge arrester according to an embodiment of the present invention includes a switching unit connected to a gas-insulated electric equipment in which insulating gas is sealed, and switching a limited voltage of the surge arrester into a limited voltage smaller than a low-temperature critical voltage indicating a withstand voltage generating a dielectric breakdown when the insulating gas is liquefied.
    Type: Grant
    Filed: May 31, 2012
    Date of Patent: April 22, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Kazuhide Bannai
  • SURGE ARRESTER AND GAS-INSULATED ELECTRIC APPARATUS
    Publication number: 20120320488
    Abstract: A surge arrester according to an embodiment of the present invention includes a switching unit connected to a gas-insulated electric equipment in which insulating gas is sealed, and switching a limited voltage of the surge arrester into a limited voltage smaller than a low-temperature critical voltage indicating a withstand voltage generating a dielectric breakdown when the insulating gas is liquefied.
    Type: Application
    Filed: May 31, 2012
    Publication date: December 20, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Kazuhide BANNAI
  • Gas insulated circuit breaker system and gas insulated circuit breaker monitoring method
    Patent number: 8199445
    Abstract: A gas insulated circuit breaker system has: a container that encapsulates insulating gas; a main contact in the container that opens/closes the main circuit; a resistor contact in the container, connected in parallel to the main contact, to be opened after elapse of a predetermined time after the main contact is opened and to be closed at a predetermined time before the main contact is closed; a resistor in the container, serially connected to the resistor contact and connected in parallel to the main contact together with the resistor contact; a temperature sensor that measures temperature of surrounding of the resistor; and a temperature estimation section that estimates a temperature of the resistor based on a timing of opening/closing operation of the main contact, a current flowing through the main circuit and the measured temperature.
    Type: Grant
    Filed: October 16, 2009
    Date of Patent: June 12, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shiro Maruyama, Takashi Nakajima, Hiroyuki Hayata, Kazuhide Bannai, Kozo Matsushita, Hideo Ishizuka
  • GAS INSULATED CIRCUIT BREAKER SYSTEM AND GAS INSULATED CIRCUIT BREAKER MONITORING METHOD
    Publication number: 20100102036
    Abstract: A gas insulated circuit breaker system has: a container that encapsulates insulating gas; a main contact in the container that opens/closes the main circuit; a resistor contact in the container, connected in parallel to the main contact, to be opened after elapse of a predetermined time after the main contact is opened and to be closed at a predetermined time before the main contact is closed; a resistor in the container, serially connected to the resistor contact and connected in parallel to the main contact together with the resistor contact; a temperature sensor that measures temperature of surrounding of the resistor; and a temperature estimation section that estimates a temperature of the resistor based on a timing of opening/closing operation of the main contact, a current flowing through the main circuit and the measured temperature.
    Type: Application
    Filed: October 16, 2009
    Publication date: April 29, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shiro MARUYAMA, Takashi Nakajima, Hiroyuki Hayata, Kazuhide Bannai, Kozo Matsushita, Hideo Ishizuka