Patents Examined by Chistine Oda
  • Vacuum switch including vacuum-measurement devices, switchgear using the vacuum switch, and operation method thereof
    Patent number: 6529009
    Abstract: A vacuum switch is composed by installing a vacuum circuit-breaker and a disconnector in different grounded vacuum vessels, respectively, and a vacuum-measurement device is attached to each grounded vacuum vessel. The above vacuum vessel communicates with one of the grounded vacuum vessels, and the degree of vacuum in the vacuum vessel can be directly measured and monitored.
    Type: Grant
    Filed: June 18, 2002
    Date of Patent: March 4, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Shuuichi Kikukawa, Katsunori Kojima, Tooru Tanimizu, Ayumu Morita, Masashige Tsuji