Patents by Inventor Efim M. Levin

Efim M. Levin 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).

  • Impeller of axial-flow fan
    Patent number: 4130381
    Abstract: An impeller of an axial-flow fan comprises a hub which carries blades installed thereon with the aid of attachment fittings in the form of a swivelling base with an extension. Each of the swivelling bases supports at least two blades. The distance between the blades installed on a single base varies from 0.15 to 0.3 .alpha. where .alpha. is the angular distance between the pivots of the adjacent swivelling bases. The blades installed on a single base are rigidly secured thereto at one end and joined to each other by a connector at the other end, thus forming a rigid system.
    Type: Grant
    Filed: June 8, 1977
    Date of Patent: December 19, 1978
    Inventors: Efim M. Levin, Vladimir P. Sysoev, Valery A. Rudenko, Oleg K. Pomazan