Patent GB-570455-A (GB)
Title: An improved aircraft
IPC: B64C27/04
Filed: 1943-09-02
Abstract: 570,455. Helicopters. CAMERON, P. Sept. 2, 1943, No. 14346. [Class 4] A helicopter is provided with load-sustaining wings 2, which carry airscrews 12 and are capable of being rotated from a normal angle of incidence into a vertical or substantially vertical position. The wings are mounted in bearings 10 and are rotated by sprocket wheels 95, Fig. 6, geared to a control wheel 88a, Fig. 12. Interlocking wedge surfaces 109 are provided to secure the wings in their normal and vertical positions respectively. The airscrews 12 are driven from the engine 13 through a gear-box 14, universal joints 15, and bevel gearing within the wings. The latter carry ailerons 17 located within the slip-streams from the airscrews, enabling the ailerons to be utilised for yaw control with the wings in their vertical position. A load-sustaining rotor 18 is driven from the engine through a clutch operated by a foot lever 104 and cable 105, Fig. 12, a vertical shaft 21 and spur gearing 22, 23. The rotor blades 3 are mounted on horizontal spindles 41, Fig. 7, carrying levers 40, whose lower ends are provided with pins engaging in inclined slots 38 formed in the periphery of a ring 37. Tilting of the latter to obtain cyclical variation of the pitch of the rotor blades is effected by four radial levers, one pair 29, 30 being mounted in the transverse plane and a similar pair in the longitudinal plane. The levers are actuated by the control column 61, Fig. 12, through cables 63, 66, 71, 74. Connected to the cables 63, 66 are further cables 64, 67, actuating the elevator 6, the ailerons 17 being actuated by pairs of cables 72, 73 and 75, 76, connected to the rotor cables 71, 74, respectively. By means of this arrangement, actuation of the elevators or ailerons is accompanied by corresponding variation of rotor blade pitch. Vertical movement of the ring 37 to effect simultaneous variation of blade pitch is effected by means of a screwed sleeve 53 actuated by a hydraulic cylinder 60 through bevel gearing 58 and spur gearing 56, 54. The hydraulic cylinder 60 is operated by a foot lever 102 and cable 103, Fig. 12. The rotor blades 3 may be extended and retracted by means of screwed rods passing through the spindles 41 and carrying bevel pinions 42 meshing with pinions 44, 45, mounted on a vertical shaft 46. The latter is provided with clutches 44a, 45a, either of which may be engaged with its associated pinion to operate the rotor blades by means of a lever 47 actuated by a control lever 97 and cable 96, Fig. 12, the shaft 46 being held against rotation by a brake 50 actuated by a further control lever 100 and cable 101. Extension or retraction of the blades may occur during a portion only of their rotation, as described in Specification 471,509. The elevator 6 and twin rudders 7 are carried on twin booms 4, the latter being operated from the rudder bar 77 through cables 79, 80, to which latter are attached further cables 86, 87, connected to the rear wheel 9 of the undercarriage. For parking purposes the wings 2 may be folded back against the body of the machine, the universal couplings 15 of the airscrew drive being disconnected to permit this, and the rotor blades 3 are turned to lie parallel with the longitudinal axis of the machine.