Patent GB-1116430-A (GB)
Title: Improvements in or relating to contra-rotating multi-stage turbines, fans or compressors
IPC: F01D1/28
Filed: 1965-06-25
Abstract: 1,116,430. Turbines; axial and radial flows fans and compressors. MASCHINENFABRIK AUGSBURG-NRNBERG A.G. and R. STROEHLEN. June 25, 1965 [June 27, 1964], No. 27035/65. Headings F1C and F1T. A contra-rotational multi-stage generator driving turbine or motor driven compressor having a hollow shaft and an inner shaft concentrically mounted therein for transmitting the output/input of the contra-rotational blade carrying members and transmission gearing for adding the output of, or dividing the input between, the members is characterized in that the inner shaft carrying a first bladed member is directly connected with a generator or motor coaxial therewith and the gearing is arranged at one end of the inner shaft, at or opposite the output or input end thereof, by which gearing, in the case of a turbine, the output of a second bladed member mounted on the hollow shaft is added to that of the first member or, in the case of a compressor, the input is divided between the two members. In a first embodiment, Fig. 1, the contra-rotational discs 4, 6 of a radial flow turbine are respectively connected to an outer shaft 1 and an inner shaft 2, the shafts being geared together at 3 so that the combined output is transmitted through a shaft 9, connected to shaft 2, to drive a generator, the windings of which are shown at 7. Heat insulating material is provided at 13 between the shafts 1, 2 and at 12 in the shaft coupling. Modified radial flow turbines having outer and inner shafts 1, 2 and transmission gearing 3 are illustrated in Figs.3, 5, 7 and 8 (not shown). Fig. 3 illustrates turbine discs bladed on both sides, Fig. 5 an arrangement in which the working steam is supplied to the turbine through ports (33) in a hollow extension (2") of inner shaft 2, and Fig.7 a brake (43) and clutch (45) so that shaft 1 can be disconnected from shaft 2 and stopped during part load running. In a further modification, Fig. 2, the invention is applied to a contra-rotational axial flow turbine having an inner drum 16 driving shaft 2 and an outer internally bladed drum formed by semi-cylindrical halves 17a, 17b bolted together at 18 and mounted between the parts 1a, 1b of the outer shaft 1. In a modification of Fig. 2, Fig. 4 (not shown), the halves 17a, 17b of the outer drum are held together by shrunk on rings (25) and the outer casing (24) corresponding to the casing 19 is circumferentially undivided. In a further modification of Fig. 2, Fig. 6 (not shown), the turbine is of the divided flow type and the working fluid is supplied to the hollow interior of the inner bladed drum (35) to issue through ports (36) into the blade flow passages. In further modifications, the invention is applied, Fig. 9 (not shown), to a turbine having combined radial flow (61, 62) and divided flow axial (64) stages, and in Figs. 10, 11 (not shown), to an axial flow fan or compressor driven by a motor connected to the inner shaft 2. The invention is also applicable to radial flow fans. The contrarotational blade carrying members may rotate at different speeds with respect to each other in each machine, these speeds being below the respective first critical speeds of the members.