Patent GB-191409177-A (GB)
Title: Improvements in and relating to Aerial Machines and Aerial Driven Watercraft.
Inventor: BELL ISAAC
IPC: B64C39/00
Filed: 1914-11-11
Granted: 1915-11-11
Abstract: 9177. Bell, I. Nov. 11. Aerial machines without aerostats; propelling.- Aerial machines and aerial-driven watercraft have supporting and propelling blades driven with substantially uniform speed over the greater part of an upward and downward path during each revolution of the propeller, means for controlling the angle of incidence of the blades to the relative wind being provided. Fig. 2 shows in plan an aeroplane having self-stabilizing supporting-planes as described in Specification 26,635/12 and fitted with one form of lifting and propelling device. Two sets of blades 52 are carried by pairs of endless belts 53 passed around pulleys 54 having forwardly-inclined axes 55 so that the belts move in a downwardly-inclined plane. The blades are capable of rocking about transverse axes and are automatically controlled in incidence by springs or by auxiliary planes mounted thereon. The blades are carried by vertical or inclined spindles preferably supported at both ends by the belts in which they may be fixed or capable of rotation. When the spindles are rotatable, the outer ends of the blades may be loaded so as to assume a radial position as they pass around the pulleys, and they may be provided with the rudder device shown in Fig. 4<q> where the blade 52 has a vane 65 mounted on a spindle 65<a> provided with an offset weight 66<a>. Under centrifugal force, the weight 66<a> turns the vane 65 into a position at rightangles to that shown, where it acts as an horizontal tail. At other times, it is held in the position shown by a spring and acts as a rudder. When the propellers stop, the blades automatically assume, under the action of the rudder, a position in which they act as supporting planes as the machine glides. Instead of turning on their vertical or inclined spindles, the blades may be controlled by auxiliary surfaces so as to turn over where necessary to assume a position suitable for gliding. The upper and lower belts are braced together so as to act as one belt which may be tensioned by a spring device acting on one of the pulleys. The belt may have pulleys working in guide rails to take centrifugal stress as the belt passes around the pulleys, or the guide rails may extend all round their path. The axes of the pulleys may be downwardly convergent to enable the belts to bow upwards slightly under the upward lift on the blades. A modification is described in which the two pairs of belts, instead of being parallel to one another as shown, are divergent in either direction so that the blades move laterally as well as up and down. In other modifications, a single set of blades is carried between two vertical or inclined belts passing around pulleys with horizontal axes. The angle of incidence of the blades. on the up and down strokes is controlled by rollers on the blades running on tracks which may be under the pilot's control, or the blades may be governed by rider planes. Fig. 6 shows a plane 70 adapted to assume a neutral or reversed position on the up-stroke. The plane is pivoted on a spindle 33 which is kept the same way up throughout its path. A wheel 34 on this shaft acts through a cord or wire 35 and arm 36 upon the rider plane 38 and causes the plane to turn upside down on the upstroke. Blades which change from convex to concave as they turn over may be used.