Patent GB-370504-A (GB)
Title: Improvements in or relating to aeroplanes
IPC: B64C27/02
Filed: 1931-01-14
Abstract: 370,504. Aircraft with rotary wing systems. HERRICK, G. P., 51, East 91st Street, New York, U.S.A. Jan. 14, 1931, No. 1261. Convention date, Jan. 23, 1930. [Classes 4 and 114.] An aeroplane is provided with a normally fixed plane which can be released for autorotation about a vertical axis for landing purposes, the plane having a profile symmetrical about the vertical axis with no pitch and being capable of tilting about a horizontal axis transverse to its length during rotation. Means for starting the rotation when the plane is released are provided. A biplane is described having a fixed lower plane 17 and an upper plane 1 capable of rotating about an axis carried by struts 21 but normally prevented from doing so by hinged struts 35 detachably secured to the plane. The section of the plane 1 is symmetrical about its maximum ordinate and is derived from a flat ellipse by upwardly arching its initially horizontal major axis into the arc of a circle, ellipse, parabola or hyperbola which forms the median line of the section. The plane may be tapered in width towards the tips and may also be tapered in thickness. The spars 24 of the plane may be connected to a rectangular frame 26, Fig. 8, pivoted about pins 28 on a ring 20 connected to the outer. member of a ball race supported on a block on the upper ends of the struts 21. The ring 20 also has pins 29 engaging slots 30 in the frame 26 to limit the tilting movements of the plane. An electromotor 11 or a flywheel device driven by a motor has a pinion 31 engaging a toothed ring 32 to enable the rotation of the plane to be started. Alternatively the block carrying the ball race may engage a quick-threaded screw shaft 2<1>, Fig. 14, so as to initiate rotation as the plane rises under lifting forces, the two parts 31, 41 of the ball bearing being locked together by members 46 until they are raised as shown by striking a collar 47 at the top of the shaft. In another modification the block carrying the ball race slides without rotation on a shaft 50, Fig. 15, and two cables 56 anchored to the aircraft are wound in opposite directions about a drum 53 connected to the outer member of the ball race. As the plane rises under lift forces or the thrust of a spring 501 the drum 53 is turned to rotate the plane until the ends of the cables, which have open hooks, become detached from the drum. Alternatively rotation of the wing may be initiated by means of deformable or adjustable parts thereon so as to vary the drag on the two sides of the machine, or rockets may be provided on the trailing edges. The plane is normally locked against rotation and tilting by projections 37, Fig. 10, engaging forks on the hinged struts 35 in which they are retained by cams 38 connected to pivoted discs 40 pro. vided with levers 42. The projections 37 and corresponding forks are so shaped that as the plane commences to rotate the struts 35 are thrust outwards and fall clear. In a simpler form, tilting of the plane is prevented or limited by a horizontal ring, engaging its under surface, which can be raised and lowered by the pilot.