Patents by Inventor Iwao Kawamata

Iwao Kawamata 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).

  • Voltage nonlinear resistor, lightning arrester equipped with voltage nonlinear resistor, and process for producing voltage nonlinear resistor
    Patent number: 8562859
    Abstract: A voltage nonlinear resistor is made of a sintered body that mainly includes zinc oxide grains, spinel grains including zinc and antimony as main ingredients, and a bismuth oxide phase, in which the bismuth oxide phase includes at least one of alkali metals selected from the group of potassium and sodium at a ratio in the range of 0.036 at % or higher and 0.176 at % or lower. The voltage nonlinear resistor has good voltage nonlinearity and loading service life characteristics, and can be used for a lightning arrester.
    Type: Grant
    Filed: November 17, 2008
    Date of Patent: October 22, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventors: Tomoaki Kato, Iwao Kawamata, Yoshio Takada
  • VOLTAGE NONLINEAR RESISTOR, LIGHTNING ARRESTER EQUIPPED WITH VOLTAGE NONLINEAR RESISTOR, AND PROCESS FOR PRODUCING VOLTAGE NONLINEAR RESISTOR
    Publication number: 20110204287
    Abstract: A voltage nonlinear resistor is made of a sintered body that mainly includes zinc oxide grains, spinel grains including zinc and antimony as main ingredients, and a bismuth oxide phase, in which the bismuth oxide phase includes at least one of alkali metals selected from the group of potassium and sodium at a ratio in the range of 0.036 at % or higher and 0.176 at % or lower. The voltage nonlinear resistor has good voltage nonlinearity and loading service life characteristics, and can be used for a lightning arrester.
    Type: Application
    Filed: November 17, 2008
    Publication date: August 25, 2011
    Applicant: Mitsubishi Electric Corporation
    Inventors: Tomoaki Kato, Iwao Kawamata, Yoshio Takada