| 摘要 |
1,074,690. Hydraulic turbines; centrifugal pumps. ESCHER WYSS A.G. Dec. 23, 1963 [Jan. 18, 1963], No. 50723/63. Headings F1C and F1T. The runner 1 of a hydraulic pump or pumpturbine connected to a synchronous electrical machine 4 is run up to speed for its pumping function by a starting turbine 9. At starting the water level in the suction tube 6 is lowered to a point 8 and water from the inlet 11 of the starting turbine 9 is sprayed through nozzles 19 into the runner chamber 15 to exert a braking torque on the runner 1 and prevent overspeeding of the set. An adjustable throttle valve 20 controls the water flowing to the nozzles 19 and a non-return valve 21 prevents flowback through line 18 when the runner 1 has reached operating speed and the turbine 9 has been shut-off. Additional braking torque is obtained by water fed to the runner chamber 15 through throttle and non-return valves 25, 26 respectively. In a modification, the braking water is not taken from the starting turbine inlet 11 but is supplied from a separate pressurized source. In this case a shut-off valve in the braking water line is connected to operate simultaneously with the starting turbine shut-off valves 13, 14. In a further modification, Fig. 2 (not shown) the starting turbine runner (27) has a centrifugal pump impeller (28) integral therewith. The impeller (28) communicates with the turbine draft tube (30) through a passage (31) in the runner hub having a non-return valve (32) which opens at a speed above the working speed of the machine being started but below the runaway speed. Thus water is pumped back from the draft tube (30) to the turbine inlet (29) to exert a braking torque on the runner.
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