Patents by Inventor Tadatsugu Yamamura

Tadatsugu Yamamura 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 for marine propulsion device
    Patent number: 6857919
    Abstract: An impeller for a jet propulsion device includes at least one fluid channel formed on each impeller blade. During impeller rotation, a fluid back-flow is generated through the fluid channels. The back-flow advantageously sweeps cavitation bubbles away from the impeller blades and inhibit their implosion on the blade surfaces and/or inner housing surface which lies adjacent the blade tips. This desirably reduces erosion and provides a long-life and efficient propulsion device.
    Type: Grant
    Filed: September 19, 2001
    Date of Patent: February 22, 2005
    Assignee: Yamaha Marine Kabushiki Kaisha
    Inventors: Yasuhiko Henmi, Tadatsugu Yamamura
  • Impeller for marine propulsion device
    Publication number: 20040009718
    Abstract: An impeller for a jet propulsion device includes at least one fluid channel formed on each impeller blade. During impeller rotation, a fluid back-flow is generated through the fluid channels. The back-flow advantageously sweeps cavitation bubbles away from the impeller blades and inhibit their implosion on the blade surfaces and/or inner housing surface which lies adjacent the blade tips. This desirably reduces erosion and provides a long-life and efficient propulsion device.
    Type: Application
    Filed: September 19, 2001
    Publication date: January 15, 2004
    Inventors: Yasuhiko Henmi, Tadatsugu Yamamura
  • Water preclusion system for watercraft exhaust
    Publication number: 20020094732
    Abstract: An exhaust system for a watercraft includes a water trap arranged on a first side of a hull tunnel, a discharge port arranged on a second side of the hull tunnel, and a chamber branched from and communicating with an exhaust passage connecting the watertrap with the discharge port.
    Type: Application
    Filed: April 27, 2001
    Publication date: July 18, 2002
    Inventors: Tatsuya Yoshida, Tadatsugu Yamamura
  • Water preclusion system for watercraft exhaust
    Patent number: 6261140
    Abstract: An exhaust system for a watercraft includes a water trap arranged on a first side of a hull tunnel, a discharge port arranged on a second side of the hull tunnel, and a chamber branched from and communicating with an exhaust passage connecting the watertrap with the discharge port.
    Type: Grant
    Filed: October 19, 1999
    Date of Patent: July 17, 2001
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Tatsuya Yoshida, Tadatsugu Yamamura