Patent GB-880417-A (GB)
Title: Extensible device for aircraft wings
IPC: B64C9/16
Filed: 1958-05-07
Abstract: 880,417. Wing flaps on aircraft. GERIN, J. J. M. J. May 7, 1958 [May 13, 1957 ; Sept. 23, 1957], No. 14643/58. Class 4. An aircraft wing has extensible means for increasing the drag and lift coefficients of the wing, wherein the extensible means comprises a slot, a first and second flap entirely retractable into the wing during cruising flight and a mechanism for positioning the slot forwardly of the wing, the first flap substantially wholly rearwardly of the wing, and the second flap substantially wholly rearwardly of the first flap. The aircraft which is intended for a wide range of flying speeds, has a small heavily loaded main wing 1 provided with trailing edge flaps 6, 7 and a leading edge slat 9 which may be extended from one position, Fig. 10, wholly enclosed within wing 1 to extended positions, Fig. 7. In an extreme lower position they lie substantially on the arc of a circle to form a heavily cambered wing, and at an intermediate position with the slat and flaps substantially co-planar the slats between the wing and flaps are closed. Flap 6 is operated and partially supported by a pair of arms 5A, 5B pivotally secured at their lower ends to further arms 2A, 2B which are pivoted at 3 to the wing 1 and connected by pivots 23A, 23B intermediate their ends to arms 4A, 4B operated in unison by a common motor by a screw and nut mechanism 24A, 24B, 25A, 25B to swing arms 2A, 2B from positions within the wing to extended positions such as shown in Fig. 13. During the initial stage of such movement arms 2A, 2B and 5A, 5B are locked together to move in unison about pivot 3. The arms 2A, 2B are also pivoted to the rear ends of members 31A, 31B which have lugs 32A, 32B as their forward ends to engage fixed tracks 33A, 33B and are formed with slide ways 34A, 34B for rollers 35A, 35B freely pivoted on the lateral faces of flap 6. Other supports (not shown) forward of the leading edge of flap 6 engage slide-bars (not shown) and operating mechanism (not shown) moves the flap rearwardly on such supports until a position is reached in which rollers 35A, 35B become disengaged from slideways 34A, 34B and the flap is supported only forward of its leading edge and by arms 5A, 5B which are provided with an automatically operated locking mechanism, Figs. 14-16 (not shown). Arms 2A, 2B and 4A, 4B are formed as casings inside which are disposed chains 27A, 27B and 28A, 28B respectively which are driven by a motor, (not shown), to swing struts 5A, 5B about its lower pivot on arms 2A, 2B. The flap 7 carries at its ends arms 69A, 69B, Fig. 23, provided with lugs 70A, 70B, to be described, and slide bars 74A, 74B which bear on the upper smooth faces of racks 75A, 75B. The slide bars carry pivots for pinions 76A, 76B which mesh with the toothed under-surface of the racks and are driven in unison by a common motor housed in flap 7 to cause the flap to move rearwardly with the arms 69A, 69B bearing on the undersurface of flap 6. At the rearward limit of travel the lugs 70A, 70B are engaged by a toggle mechanism, Figs. 27-30 (not shown), which locks flap 7 to flap 6 in an extended position. Slat 9 is supported on each lateral extremity by pivots 54A1, 54B1 on the forward ends of collapsible arms 8A, 8B which may be hinged about vertical pivots 54A2, 54B2 carried by plates 55A, 55B in turn mounted on transverse pivots 56A, 56B for rotation by the application of forces F4 to members 57A, 57B. Arms 8A, 8B are extended and collapsed by a link and endless chain mechanism 60. During extension and retraction of the slat it is supported by arms 62A, 62B which slide within fixed supporting members 63A, 63B, the ends of the arms being bevelled as at 64A, 64B to enable the flap to be inclined downwardly at the outer limit of its movement. The camber of the flaps may be adjusted differentially to provide lateral control of the aircraft. The aircraft housing such flaps and slats comprises a central fuselage and two outer nacelles each housing a power plant and undercarriage, the fuselage and nacelles being connected by a wing 1 and tail plane, which are both braced by lift struts. The wing comprises a Warren-braced spar L.