The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 23, 2010
Filed:
Oct. 11, 2006
Kazuyuki Nakamura, Tokyo, JP;
Kotaro Tezuka, Tokyo, JP;
Toshifumi Kurokawa, Tokyo, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
A Francis pump-turbine includes a runner provided with runner blades arranged around in a circumferential direction of a main shaft of the runner, each of the runner blades being supported by a band at a bottom side thereof in a blade height direction and supported by a crown at a head side in the blade height direction, in which the runner blade is formed, at a trailing edge thereof, with a curved portion expanding to the main shaft when the turbine is in operation, the curved portion has a maximum point with respect to a straight line connecting a crown-side trailing edge connecting end at which the trailing edge and the crown are connected and a band-side trailing edge connecting end at which the trailing edge and the band are connected, and an angle α formed by a straight line connecting the maximum point and the crown-side trailing edge connecting end and a straight line connecting the maximum point and the band-side trailing edge connecting end is set to be within a range of α≦150°.