Patent GB-601911-A (GB)
Title: Improvements in helicopters
IPC: B64C27/18
Filed: 1945-08-03
Abstract: 601,911. Helicopters. ISACCO, V. Aug. 3, 1945, No. 20051. [Class 4] In a helicopter, some or all of the blades of which are provided with propulsive means (preferably jet units) adapted both to sustain and propel the machine, the fuel is fed to the propulsive means from an auxiliary reservoir in the vicinity of the axis of rotation, the main tank being in the fuselage. In the vertical section, Fig. 5, the hub 6, carrying two non- propulsive blades 7a (shown in longitudinal section) and two propulsive blades (shown by an attachment arm 78), bears the auxiliary fuel tank 56 on a cylinder 57 secured to the top of the hub, the tank thus rotating with the hub ; a pump 54 driven by gearing 51, 52 at the base of the hub 6 forces fuel from the main tank 55 through pipes 57a into the auxiliary tank 56 from which it can be delivered by pipes 60, 68 leading to the propulsive units. Instead of the auxiliary tank rotating with the hub it may be fixed and have a distributer with a part rotating withthe rotor. Control of blade pitch, of throttles for the propulsive means, and of other parts is exercised through ball bearings such as 23, mounted on the hub and operated through duplicate wires 30, 31 attached to a pin 28 to move the ball-bearing 23 which carries legs 22 connected to a leversystem for action upon the members to be controlled ; the wires are connected for actuation by the pilot to the joy-stick or to separate control-levers. The ball-bearing 23 is mounted so as to be capable of sliding vertically for actuating the parts to be controlled ; the uppermost ball-bearing 40, which controls ailerons mounted at the outer ends of the blades, does not slide but is universally mounted to obtain a periodic variation of aileron action ; in a similar manner a universally-mounted bearing is used for periodic variation of bladepitch. In a modification, Fig. 12 (not shown), a single universally-mounted ball-bearing is used in the simultaneous control of a periodic pitch-variation mechanism and of a general pitch-variation mechanism. In Fig. 8 is shown a blade 7 with a horizontal joint, arranged to be in a direction, which is not perpendicular to the longitudinal axis of the blade so that lifting or depression of the blade may produce a change in pitch ; the joint comprises duplicate parts 80. Gearing for rotating the ailerons 9, shown in Fig. 10, and referred to above, as operated from bearing 40, is connected to wires 48 turning the gearing to operate a lever 95 on shaft 93 ; the jet unit 8 is at the outer end of the blade. The vertical rudder, Fig. 13, comprises two parts 5, 5a connected by vertical hinging, the part 5a being mounted to turn on a fixed horizontal axis X2-X2 so that when lever 141 is turned by the attached wires the two rudder-parts turn about X2-X2 and part 5 is turned about the normally vertical hinging connecting the two parts ; when the ailerons are in movement, their downward air stream will act upon the rudder inclined about the horizontal and produce a steering torque for control in yaw while hovering and while in horizontal flight. Means are provided for holding the rotor blades stationary while the propulsive means are being started up. Specifications.250,534 and 332,312, [both in Class 4], are referred to.