Patents by Inventor Kooju Aizawa

Kooju Aizawa 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).

  • Bearing unit, drainage pump and hydraulic turbine each incorporating the bearing unit
    Patent number: 5346316
    Abstract: Disclosed is a bearing unit which can be used in a drainage pump operated without supply of clean water or a hydraulic pump, which exhibits excellent wear resistance against water containing earth and sand and satisfactory assembling facility, and a method of manufacturing the bearing unit.The contact surface of a bearing made of stainless steel and/or that of a sleeve is applied with a sprayed coating, the main component of which is WC, and which contains one or more elements selected from a group consisting of nickel, chromium and cobalt as a binder material thereof, or a sprayed coating, the main component of which is Cr.sub.3 C.sub.2, and which contains NiCr as a binder material, after the sprayed coating has been formed, heating at from 300.degree. C. to 550.degree. C. is performed for one hour or longer so that hardness and wear resistance equivalent to those of a WC - 12% sintered article is attained.
    Type: Grant
    Filed: March 18, 1993
    Date of Patent: September 13, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Ryoji Okada, Kooju Aizawa, Masayuki Yamada, Kenji Otani, Kunio Takada, Mitsuaki Haneda, Toshihiro Yamada