Patent US 4,351,502

An actuating mechanism for variable camber edges of aerodynamic airfoils--viz., variable camber leading edges and/or variable camber trailing edges--characterized by its rigidity and structural stability and which permits varying the camber of a flexible continuous airfoil skin while maintaining a uniform, essentially constant curvature throughout the chordal extent of deflection for any given degree of deflection; yet, wherein (a) the airfoil skin (i) is not required to function as a load carrying element, (ii) is not subjected to chord-wise stress from movement of the actuating linkage, and (iii) is not subjected to localized stress resulting from localized deflection; (b), the actuating linkage is contained entirely within the airfoil aerodynamic contour at all operating positions; (c), the actuating linkage is readily adaptable for use with, and is compatible with, virtually any conventional structural wing box without requiring modification of the wing box structure and without compromise to wing box location and/or extent; and (d), which permits of optimized negative (down) and positive (up) deflection of a desired airfoil edge so as to permit attainment of differing optimized airfoil performance characteristics for virtually any type of airfoil. More specifically, the present invention pertains to simplified actuating linkages for continuous skin variable camber airfoil edges comprising only two sets of 4-bar linkages--viz., one set to control horizontal and vertical displacement of the structural member defining the airfoil edge, and the other set controlling the angle of rotation of such structural member and the moment applied to the end of the flexible skin panel.