GB832365A - Device permitting the automatic alteration of the transmission ratio in a mechanism consisting of a linkage between two rods - Google Patents

Abstract

832,365. Linkwork. NORD-AVIATION SOC. NATIONALE DE CONSTRUCTIONS AERONAUTIQUES, [formerly SOC. NATIONALE DE CONSTRUCTIONS AERONAUTIQUES DU NORD.]. Dec. 13, 1956 [March 13, 1956], No. 38103/56. Class 80 (3). A linkage, particularly for the control mechanism of an aerodyne control surface, is adapted to provide an automatic variation in the transmission ratio during operation of the mechanism, as shown, on actuating rod 1 from the cockpit of an aircraft is coupled to a lever 4 which is coupled by another link 2 to one arm 11 of a quadrilateral 9, 10, 11, 12, mounted upon a fixed axis O, O<SP>a</SP>, an extension of the arm 11 being coupled to a rod 5 connected to a control surface of the aircraft. The quadrilateral 9, 10, 11, 12 is also controlled by a rod 3 between the lever 4 and the arm 10 of the quadrilateral so that as the rod 1 is moved from one position to another the distance between the axis O, O<SP>a</SP> of the quadrilateral and the pivot 8 to which the link 2 is connected is varied which results in an automatic variation of the transmission ratio between rods 1 and 5. In a modified arrangement the rod 3 is connected between an extension of the lever 4 beyond its axis O1 O1<SP>a</SP> and an extension of the arm 10 of the quadrilateral. When the travels of the control column and control surface are not symmetrical on either side of the neutral position the rod 3 may be duplicated, one rod acting in compression only and the other in tension. Alternatively a single rod 3 may be split and coupled to an intermediate rocking lever. In another arrangement the rod or rods 3 are omitted and the arm 10 of the quadrilateral is fixed.