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. 01, 1994
Filed:
Mar. 12, 1992
Sachio Tsunoda, Yokohama, JP;
Hiroshi Tanaka, Yokohama, JP;
Ichiro Yamagata, Yokohama, JP;
Shigeto Fujiki, Fujimi, JP;
Yoshikazu Kobayashi, Ichikawa, JP;
Akira Terasaki, Utsunomiya, JP;
Kabushiki Kaisha Toshiba, Kawasakishi, JP;
Abstract
When the trigonometric function of the phase lag of the hydraulic excitation of the runner vanes, which varies in accordance with the combination of the number of runner vanes and the number of guide vanes of a high head pump/turbine, is denoted by cos(.theta..sub.R n), the thickness of the crown along a circle of a diameter at a mid point of the diameter of the outermost periphery of the runner is denoted by t.sub.MC, the thickness of the band is denoted by t.sub.MB, the mean thickness of the crown at the outer peripheral portion of the runner is denoted by t.sub.C, the mean thickness of the band is denoted by t.sub.B, and the rigidity ratio of the crown and band to the runner vane is denoted by K.sub.R taking the rigidity of the runner vane as a reference, the moment coefficient C.sub.MO which is a function of cos(.theta..sub.R N) and the rigidity ratio K.sub.R is selected to be less than 0.5 in accordance with the value of cos(.theta..sub.R n), and relations t.sub.C /t.sub.MC .ltoreq.1 and t.sub. B /t.sub.MB .ltoreq.1 are selected when the value of cos(.theta..sub.R m) is positive and relations t.sub.C /t.sub.MC .ltoreq.1 and t.sub.B /t.sub.MB .ltoreq.1 are selected when the value of cos(.theta..sub.R n) is negative.