Cycloidal Propeller

摘要

1,153,137. Cycloidal propellers. HOVERCRAFT DEVELOPMENT Ltd. 26 Aug., 1966 [31 Aug., 1965], No. 37121/65. Headings B7G and B7K. [Also in Division F2] A propeller for use in air or water comprises a series of parallel blades 10a to 10l, Fig. 3, rotatable about a common axis X, maintaining a fixed angle between the blade chord and its radius from X with means A, A1 for varying the blade lift F, F1 while rotating so as to produce a resultant flow R of fluid normal to the axis X. The lift varying means A, A1 on each blade may be either at least one jet of fluid, Fig. 6, or at least one spinning cylinder 60a, 60b, Fig. 12; or rudders, or flaps or a belt moving round the surface of the blade 10. The blade 10, Fig. 6, for the fluid jet lift varying means comprises an inlet duet 13 and outlet ducts 17, 18, 25 near the tail of the blade, the fluid jet be directed into either duct 17 or 18 by a high-pressure cross jet supplied from duct 23 or 22 respectively. The control of the fluid supply to the ducts 13, 22, 23 may be as shown in Fig. 7 where the duct inlets 13a, 22a, 23a in the rotating disc 11 are fed from grooves 13b, 22b, 23b respectively in the stationary disc 50, whose position can be varied to change the resultant direction of propeller thrust F R , Fig. 3. The propeller 101 may be used on an air cushion vehicle 100, Fig. 15, where the mounting ring 11 for the blade 10 is fitted into a hollow 45 in a fairing 46, the outer ends of the blades being connected to a ring or disc 11a to assist in mechanical stability, reduce entanglement with tree branches, and reduce vortices at the blade ends. A motor 107 on the vehicle 100 drives a compressor 106 to supply air, drawn in at 105 to provide the air cushion.