GB1069627A - Improvements in or relating to hydraulic turbines,pumps,and reversible pump turbines - Google Patents

Abstract

1,069,627. Hydraulic turbines; centrifugal pumps. ENGLISH ELECTRIC CO. Ltd. March 11, 1964 [March 11, 1963], No. 9597/63. Headings F1C and F1T. A hydraulic turbine, pump or reversible pump turbine comprises a plurality of variable pitch blades 13, Fig. 1, pivotally mounted in a runner and rotatable about axes 16, which meet at a common point on the axis of rotation 17 of the runner but which are not coplanar, an operating lever 20 connected to each blade, links 40 each connecting a member 35 to an operating lever, the links being capable of limited universal movement relative to both the operating levers and the member 35, and servomotor means operable to move the member 35 along the axis 17 and thus vary the pitch of the blades. Each operating lever 20 is secured to a blade trunnion 21 by a nut 22 and keyed to the trunnion to rotate with it. The universal movement of the link 40 is provided by part-spherical joints 42, 43 and 45, 46, Fig. 2. Each links 40 is approximately perpendicular to its corresponding blade's axis of rotation 16 and lies substantially in a plane passing through the runner axis 17. Packing washers 39 between the links 40 and member 35 may be varied in thickness to determine the initial pitch of each blade 13. As shown in Fig. 1, the member 35 comprises a frusto-conical flange secured to a cylinder 25 which slides on bearings 26 and 27 and co-operates with a fixed piston 23. Hydraulic fluid under pressure is supplied to the spaces 34 and 33, respectively above and below the piston 23, through annular channels 32 and 31 respectively. In a modification, Fig. 3 (not shown), the cylinder 125 is fixed to the runner casing and the piston 123 has a piston rod 124 to which member 35 is secured. In a further modification, the servo piston and cylinder may be located outside the body of the runner and connected to member 35 through a piston rod.