Patents by Inventor Tokio Fukai

Tokio Fukai 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).

  • Screw-type dry vacuum pump having an enlarged casing portion
    Patent number: 6655938
    Abstract: A screw-type dry vacuum pump comprises a rotor having a screw thread thereon for exhausting a gas through rotation, a casing for housing the rotor therein, a reduced portion provided in the casing, and an enlarged portion provided on a discharge end of the casing. The reduced portion forms a slight gap between the outer circumferential surface of the rotor and the inner surface thereof. The enlarged portion forms a larger gap between the outer circumferential surface of the rotor and the inner surface thereof.
    Type: Grant
    Filed: November 5, 2001
    Date of Patent: December 2, 2003
    Assignee: Ebara Corporation
    Inventors: Kiyoshi Yanagisawa, Tokio Fukai
  • Screw-type dry vacuum pump
    Publication number: 20020057964
    Abstract: A screw-type dry vacuum pump comprises a rotor having a screw thread thereon for exhausting a gas through rotation, a casing for housing the rotor therein, a reduced portion provided in the casing, and an enlarged portion provided on a discharge end of the casing. The reduced portion forms a slight gap between the outer circumferential surface of the rotor and the inner surface thereof. The enlarged portion forms a larger gap between the outer circumferential surface of the rotor and the inner surface thereof.
    Type: Application
    Filed: November 5, 2001
    Publication date: May 16, 2002
    Applicant: Ebara Corporation
    Inventors: Kiyoshi Yanagisawa, Tokio Fukai