06768218 is referenced by 12 patents.

According to the small hydroelectric power generator of the present invention, each of the outer peripheral portions of the hydraulic turbine which oppose to the ejecting openings are made in an edge shape. Therefore, the ejecting openings will not be blocked by the outer peripheral portions of the hydraulic turbine, keeping the hydraulic pressure constant. Also, since the water is constantly ejected from the ejecting openings at a plurality of locations, the hydraulic turbine rotates smoothly, reducing the rotational noise. Furthermore, the hydraulic pressure and the current are kept constant and in turn the vibration noise from the case and the current noise are reduced. Moreover, the square corners and the edges are eliminated from the back planes of the blade members to give an R-like round shape; therefore, a reverse torque is prevented from occurring to smoothen the current and in turn to reduce the noise.

Title
Small hydroelectric power generator
Application Number
10/56477
Publication Number
6768218 (B2)
Application Date
January 23, 2002
Publication Date
July 27, 2004
Inventor
Yukinobu Yumita
Shimosuwa-machi
US
Agent
Reed Smith
US
Assignee
Sankyo Seiki Mfg
US
IPC
H02P 9/04
View Original Source