Patent GB-332242-A (GB)
Title: Improvements in controlling means for the movable control surfaces of aerial craft
IPC: B64C13/00
Filed: 1929-04-16
Abstract: 332,242. Molino, G., and Naef, G. April 16, 1929. Steering and balancing. - The movable control surfaces of aircraft are moved bv hydraulic means controlled by the pilot's control lever and, in some cases, by mercury levels for preserving the lateral and longitudinal balance automatically, the power fluid being derived from a pump comprising two pistons connected to different points on a wheel actuated by an auxiliary motor. Two plungers 7, Fig. 2. working in cylinders 8, side by side, are connected by rods to oppositely disposed crank pins 5 on a worm wheel 4 driven by a worm 3 normally coupled by a clutch 24 to a hollow shaft 2 provided with an airscrew 1. The plungers 7 pump fluid from a tank 9 through valves 11 and deliver it through valves 13 and pipes 15, 16 to a chamber 7 containing a ram 18 loaded by a spring 19. A reducing valve 59 connects the chamber 17 to the tank 9. As the pressure rises the ram 18 is forced out until its for ward end 18<1> strikes a pin 22 sliding in the shaft 2 and disconnects the clutch 24. During this movement a projection 60 on the ram strikes a member 61 to adjust the valve 59 through a connection 62. The pressure fluid passes through a pipe 21 to the control means and returns to the tank through a pipe 21<1>. Each control surface is provided with two arms 40, Fig. 7, connected by chains passing over pulleys 39 on the rams 37 in cylinders 36, one cylinder being connected to the pressure fluid and the other connected to exhaust at each operation of the control surface. The lateral and longitudinal stability are controlled by two mercury levels set transversely of the wings and longitudinally on the fuselage. Each level comprises two chambers 32, Fig. 9, connected by a pipe 33 containing mercury. Each chamber has a float 32<1> and the space above each float is filled with a. lighter fluid communicating by a pipe 34 to a corresponding chamber 28, Fig. 5, of a relay device. The float that rises displaces fluid to force down a. plunger 29 in the relay device to connect through an annular channel 35, a manifold 21a to a pipe 30 leading to one of the cylinders 36 on the corresponding aileron or elevator, the other cylinder being put into communication through a pipe 31 to a manifold 21'a through a second annular channel. The manifolds 21a and 21<1>a are connected respectively to the pressure and exhaust pipes 21, 21<1>. A spring returns the plunger 29 to close the passages when the pressure in the pipe 34 is released. Fig. 10 shows a manual device ior actuating the elevator and rudder. A. lever 42 ball jointed at 43 has transverse extensions 44 acting on spring-pressed plungers 45 abutting against rods 48. connected to pairs of levers 50 on shafts 51 provided with screws 52 so that rotary motion of the shafts opens and closes valves 53 in chambers 56. Four pairs of these valve chambers allow the actuating cylinders 36 of the elevator and rudder to be opened to pressure and exhaust in the appropriate directions as the lever 42 is moved. Springs 57 restore the levers 50 to their normal position when all the valves 53 are closed.